With increasing use of computed tomography (CT) in modern medicine, concerns have arisen regarding increasing radiation dose to the community from med

Size: px
Start display at page:

Download "With increasing use of computed tomography (CT) in modern medicine, concerns have arisen regarding increasing radiation dose to the community from med"

Transcription

1 Note: This copy is for your personal non-commercial use only. To order presentation-ready copies for distribution to your colleagues or clients, contact us at ORIGINAL RESEARCH PEDIATRIC IMAGING Sarabjeet Singh, MBBS Mannudeep K. Kalra, MD Michael A. Moore, MD Randheer Shailam, MD Bob Liu, PhD Thomas L. Toth, BS Ellen Grant, MD Sjirk J. Westra, MD Dose Reduction and Compliance with Pediatric CT Protocols Adapted to Patient Size, Clinical Indication, and Number of Prior Studies 1 Purpose: Materials and Methods: To assess compliance and resultant radiation dose reduction with new pediatric chest and abdominal computed tomographic (CT) protocols based on patient weight, clinical indication, number of prior CT studies, and automatic exposure control. The study was institutional review board approved and HIPAA compliant. Informed consent was waived. The new pediatric CT protocols, which were organized into six color zones based on clinical indications and number of prior CT examinations in a given patient, were retrospectively assessed. Scanning parameters were adjusted on the basis of patient weight. For gradual dose reduction, pediatric CT (n 692) examinations were performed in three phases of incremental stepwise dose reduction during a 17-month period. There were 245 male patients and 193 female patients (mean age, 12.6 years). Two radiologists independently reviewed CT images for image quality. Data were analyzed by using multivariate analysis of variance. 1 From the Department of Radiology, Massachusetts General Hospital, 25 New Chardon St, 4th Floor, Boston, MA (S.S., M.K.K., M.A.M., R.S., B.L., E.G., S.J.W.); and GE Healthcare, Waukesha, Wis (T.L.T.). From the 2007 RSNA Annual Meeting. Received August 29, 2008; revision requested October 30; revision received December 8; accepted January 29, 2009; final version accepted February 16. S.J.W. supported in part by a grant from the Society for Pediatric Radiology Research and Education Foundation. Address correspondence to S.S. ( ssingh6@partners.org ). Results: Conclusion: Compliance with the new protocols in the early stage of implementation (chest CT, 58.9%; abdominal CT, 65.2%) was lower than in the later stage (chest CT, 88%; abdominal CT, 82%) (P.001). For chest CT, there was 52.6% (9.1 vs 19.2 mgy) to 85.4% (2.8 vs 19.2 mgy) dose reduction in the early stage of implementation and 73.5% (4.9 vs 18.5 mgy) to 83.2% (3.1 vs 18.5 mgy) dose reduction in the later stages compared with dose at noncompliant examinations (P.001); there was no loss of clinically relevant image quality. For abdominal CT, there was 34.3% (9.0 vs 13.7 mgy) to 80.2% (2.7 vs 13.7 mgy) dose reduction in the early stage of implementation and 62.4% (6.5 vs 17.3) to 83.8% (2.8 vs 17.3 mgy) dose reduction in the later stage (P.001). Substantial dose reduction and high compliance can be obtained with pediatric CT protocols tailored to clinical indications, patient weight, and number of prior studies. RSNA, 2009 Supplemental material: /content/full/ /dc1 RSNA, radiology.rsnajnls.org Radiology: Volume 252: Number 1 July 2009

2 With increasing use of computed tomography (CT) in modern medicine, concerns have arisen regarding increasing radiation dose to the community from medical imaging and regarding the associated increasing estimated risk for radiation-induced cancer (1,2). With regard to risk of cancer, studies (3) have shown that children are much more susceptible to radiation than adults. Consequently, several strategies have been assessed to reduce radiation dose for children, including that described by Frush et al (4) for radiation dose optimization with weight-based color-coded protocols for CT body scanning in children. These strategies adapt fixed tube current and peak voltage according to children s weight and enable reduction of CT radiation dose for children. Use of automatic exposure control techniques for automatically adapting the radiation dose to the size of children while maintaining desired or specified image quality has also been described (5 7). In addition, studies have shown that reduced-dose CT scanning can be performed for certain clinical indications, such as for evaluation of kidney stones (8), most bone indications (9,10), follow-up head CT for assessing shunt patency in hydrocephalus (11), and follow-up chest CT for cystic fibrosis (12), bronchiectasis (13), and pulmonary nodules (14,15). However, to the best of our knowledge, no systematic method has described pediatric CT protocols that involve patient weight, clinical indication, number of prior studies, and automatic Advances in Knowledge Pediatric CT protocols based on the clinical indications for CT and the number of prior CT examinations can have up to 88% compliance. Such protocols are associated with 16% 89.5% radiation dose reduction for pediatric chest and abdominal CT studies. Lesion conspicuity and diagnostic acceptability were acceptable with low radiation dose chest and abdominal CT performed in compliance with these new protocols. exposure control for optimizing radiation dose. Therefore, the purpose of our study was to assess compliance and radiation dose reduction with new pediatric chest and abdominal CT protocols based on patient weight, clinical indication, number of prior CT studies, and combined modulation automatic exposure control. Materials and Methods An author (M.K.K.) received research funding from GE Healthcare (Waukesha, Wis). An author (T.L.T.) is an employee of GE Healthcare. The remaining authors (S.S., M.A.M., R.S., B.L., E.G., S.J.W.) have no financial disclosures and had complete unrestricted access to data at all stages of the study. Patients The study was approved by the human research committee of the institutional review board and was compliant with Health Insurance Portability and Accountability Act guidelines. The requirement for informed consent was waived. To reduce radiation dose in a graded manner to allow the radiologists and the technologists to get used to noisier images associated with CT examinations with lower radiation dose, the division of pediatric radiology at our institution introduced new protocols in three phases for gradual incremental stepwise reduction in CT radiation dose for children (phase 1: January 1, 2007 to October 31, 2007; phase 2: November 1, 2007 to February 28, 2008; phase 3: March 1, 2008 to May 31, 2008) (Appendix E1, http: //radiology.rsnajnls.org/cgi/content/full / /DC1). Consecutive pediatric patients ( 18 years) undergoing chest or abdominal CT studies performed between January 1, Implication for Patient Care Weight-based protocols for radiation dose reduction in children can be structured to adapt radiation dose to clinical indications, presence of prior CT, and body region and May 31, 2008 were included in our study. The study cohort consisted of 692 CT examinations (chest CT, n 328; abdominal CT, n 364) performed in 438 children (245 male patients, 193 female patients; age range, 0 18 years; mean age, 12.6 years) (Fig 1). Scanning Protocols All pediatric patients were scanned with an eight-section (LightSpeed Ultra; GE Healthcare), 16-section (LightSpeed 16; GE Healthcare), or 64-section (Light- Speed VCT; GE Healthcare) multidetector CT scanner. Color zones. For each phase, the new CT protocols were divided into six color zones based on clinical indication and presence of one or more prior CT examinations performed at our institution. These zones included pink (most routine indications or rule-out situations; eg, to rule out appendicitis), green (follow-up CT with one prior CT examination performed at our institution; eg, first follow-up of liver abscess), red (index CT for bone evaluation or multiple prior CT examinations performed for the same abnormality and body region; eg, bone fractures or deformity or multiple prior CT examinations performed for pancreatic pseudocyst or pneumonia follow-up), yellow (kidney stone), blue (subtle or small lesions suspected or identified with other imaging results or with clinical examination results), and gray (vascular assessment with CT angiography). The decision Published online before print /radiol Radiology 2009; 252: Author contributions: Guarantors of integrity of entire study, M.K.K., M.A.M., S.J.W.; study concepts/study design or data acquisition or data analysis/interpretation, all authors; manuscript drafting or manuscript revision for important intellectual content, all authors; manuscript final version approval, all authors; literature research, S.S., M.K.K., M.A.M., B.L., E.G., S.J.W.; clinical studies, S.S., M.K.K., M.A.M., R.S., E.G., S.J.W.; statistical analysis, S.S., M.K.K.; and manuscript editing, M.K.K., M.A.M., B.L., T.L.T., E.G., S.J.W. See Materials and Methods for pertinent disclosures. See also the editorial by Frush in this issue. Radiology: Volume 252: Number 1 July 2009 radiology.rsnajnls.org 201

3 about the use of the pink, green, or red zone in patients with known malignancy undergoing follow-up CT scanning was left to the individual radiologist. Weight categories. To adapt radiation dose to patient weight, each zone was further divided into four (for phases 1 and 2) or five (for phase 3) categories on the basis of patient weight (Table 1). These weight categories were set arbitrarily to enable selection of specific voltage for different-sized patients, as well as noise indexes used in our study. Scanning parameters pertaining to the color zones and their weight categories were archived on each scanner and were named (eg, pink 0 9 kg, pink kg, and so on for each of the four or five weight categories belonging to the six color zones). Archiving and naming these protocols in the scanner allowed technologists to select and scan by using the preloaded protocols, without making any changes to scanning parameters. Automatic exposure control. All studies were performed by using a combined modulation type (AutomA 3D; GE Healthcare) of automatic exposure control. The noise indexes for the automatic exposure control technique used in the new protocols were selected empirically on the basis of prior studies in adult patients of different sizes (16,17). These patient studies showed that the use of a lower noise index was necessary for smaller adult patients ( 27.2 kg) compared with larger adults. In the study of Kalra et al (16), the authors also described the use of a cone-shaped phantom to document the fact that lower noise indexes should be used for smaller objects compared with average-sized or larger objects. Thus, a noise index of 10 used in this study for smaller patients was selected for larger children ( 45.4 kg) for the new pink protocol. For smaller children, the noise indexes were decreased empirically. Furthermore, the use of different noise indexes for different clinical indications, such as kidney stone protocol, has also been reported for achieving higher dose reduction (8). CT workflow with new protocols. On receiving a request for CT examination in a child, a pediatric radiologist specified the zone on the basis of clinical indication, body region, and images from prior CT studies available in the picture archiving and communication system and/or radiology information system. The color zone was specified on an online protocoling system (IDxRAD; GE Healthcare) available at our institution. For example, for ruling out appendicitis, the radiologist specified pink in the protocoling system, whereas for a kidney stone, yellow was specified. Figure 1 Figure 1: Flowchart depicts patient demographics in the three phases of incremental dose reduction for implementation of new pediatric CT protocols. MDCT multidetector CT scanner, n number of CT examinations. 202 radiology.rsnajnls.org Radiology: Volume 252: Number 1 July 2009

4 On the basis of the patient weight at the time of scanning, a weight category was selected for each color zone recommended by the radiologist. When radiologists were unavailable prior to scanning or when the scanning indication was emergent, technologists were instructed to use the pink zone, the default zone of radiation dose, and guess Table 1 New Pediatric CT Protocols for Chest and Abdominal Examinations Zone and Weight Category Voltage (kvp) Tube Current Range (ma) the weight of the child to determine the appropriate weight category. Phase 1 Noise Index Phase 2 Noise Index Pink 0 9 kg kg kg kg kg NA NA 15 Green 0 9 kg kg kg kg kg NA NA 16 Red 0 9 kg kg kg kg kg NA NA 18 Yellow 0 9 kg kg kg kg kg NA NA 17 Blue 0 9 kg kg kg kg kg NA NA 14 Gray* 0 9 kg kg kg kg kg NA NA 15 Phase 3 Noise Index Note. Radiation dose for color zones and weight categories was adapted by using appropriate noise index, tube current range, and voltage. For phase 3, a fifth weight category was added for heavier patients to improve compliance, and pitch was increased for all weight categories to lower radiation dose. NA not applicable. * Despite lower tube currents for kg patients in the gray zone compared with those of the kg group, dose was greater for the former category because of higher voltage. Assessment of Compliance with New Protocols Patient age, sex, and weight, type of examination (chest or abdominal), color zone and weight category used for scanning, and date of examination were recorded. In addition, we also recorded all scanning parameters, as well as the CT dose descriptors CT dose index volume (in milligrays) and dose-length product (in milligray-centimeters). For each CT examination, two authors (S.S. and M.K.K., with 1 and 9 years of experience, respectively) matched the scanning parameters used by technologists with those specified for the color zone and weight category. A CT examination was labeled as compliant with the new protocol when all scanning parameters were correctly used by the technologist for that specific color zone and weight category. CT examinations performed with the use of incorrect scanning parameters were labeled as noncompliant examinations. On CT images, an author (S.S.) measured the maximum skin-to-skin transverse diameter of the chest (just above the diaphragm for all chest CT studies) and the abdomen (above the anterior superior iliac spine for all abdominal CT studies). These parameters were also recorded for prior CT examinations, if available, to compare radiation dose between the new and the prior protocols. Image Quality Assessment Two radiologists (S.J.W., with 22 years of subspecialty experience; R.S., with 6 years of experience) reviewed representative consecutive chest (n 30 for phase 1, n 33 for phase 2, n 50 for phase 3) and abdominal (n 41 for phase 1, n 45 for phase 2, n 50 for phase 3) CT examination results included in our study on a picture archiving and communication system diagnostic workstation (Impax ES; AGFA Technical Imaging Systems, Ridgefield Park, NJ). All consecutive chest and abdominal CT studies performed within 2 weeks of implementation of each phase were reviewed, regardless of study indication, color zone, or weight category. Both radiologists independently evaluated image quality of randomized images obtained with and without the use of the new protocols on a picture archiving and communication system workstation. The radiologists were informed about the phase of study to be reviewed but were not aware of the identity of compliant and noncompliant exam- Radiology: Volume 252: Number 1 July 2009 radiology.rsnajnls.org 203

5 Table 2 Distribution of Patients Scanned according to Color Zones during Three Phases of Implementation of New CT Protocols Parameter inations, patient demographics, and the date of examination when evaluating for image quality. Image quality was assessed in terms of subjective image noise, beam hardening, visibility of small structures, lesion size, lesion conspicuity, lesion attenuation, and diagnostic acceptability. If there were multiple lesions, the readers were asked to grade the smallest lesion. In case of a discrepancy between the two readers, a study investigator (S.S.) informed the readers about the lesions that should be evaluated. Subjective image noise was graded with a five-point scale based on presence and amount of image mottle or graininess (1 minimal image noise, 2 less than average noise, 3 average image noise, 4 above average noise, 5 unacceptable image noise). The visibility of small structures was also graded by using a fivepoint scale, with 1 indicating excellent visualization and 5 indicating unacceptable visualization of small structures. Beam hardening or streak artifacts were graded with a five-point scale (1 artifacts affecting the interpretation of a lesion or an organ of interest, 2 pronounced artifacts interfering with diagnosis although a diagnosis can be made, 3 moderate artifacts slightly interfering with diagnostic decision making, 4 mild artifacts not interfering with diagnostic decision making, and 5 complete absence of artifacts). Diagnostic acceptability for clinical interpretation of the study was evaluated with a four-point scale, which included fully acceptable (grade 1), probably acceptable (grade 2), acceptable only in limited conditions (grade 3), and diagnostically unacceptable (grade 4). Lesion conspicuity was ranked with a five-point scale, with a score of 5 indicating a wellseen lesion with well-visualized margins and a score of 1 indicating a definite artifact mimicking a lesion. Most assessed image quality attributes used in our study have been described in the European Guidelines on Quality Criteria for Computerized Tomography document (18). In addition to the subjective assessment of image quality, objective image noise and CT numbers (in Hounsfield units) were measured (S.S.) for CT examinations included in the present study. For all chest CT studies (n 113) evaluated by the radiologists, a circular region of interest (10 20 mm 2 based on the size of aorta) was drawn in the descending thoracic aorta at the level of the carina. For all abdominal CT studies (n 126) assessed by the radiologists, a region of interest was drawn in the homogeneous area of the right lobe of liver (20 30 mm 2 ) or in the paraspinal muscles (20 30 mm 2 ) in the presence of heterogeneous liver parenchyma. Data and Statistical Analysis Data were analyzed by using software (SAS, version 9.1.3, SAS Institute, Cary, NC; SPSS, version 13.0, SPSS, Chicago, Ill). Means standard deviations of patient age, weight, and transverse diameter, CT dose index volume, and doselength product were estimated for each color zone and weight category and were compared by using multivariate analysis of variance (SAS statistical software). Image quality scores as described previously were also assessed for each zone and category to determine the number of suboptimal studies by using Wilcoxon signed rank tests (SPSS software). Compliance with the new protocols in each phase of dose reduction was determined by assessing the recorded scanning parameters for each patient and counting the number of compliant and noncompliant examinations during the study period. Radiation dose (CT dose index volume and dose-length product), patient age, No. of Phase 1 Patients No. of Phase 2 Patients No. of Phase 3 Patients Zone Pink 40 (89) 67 (95) 53 (53) Green 75 (108) 28 (67) 24 (24) Red 4 (4) 6 (6) 7 (7) Yellow 13 (13) 4 (6)... Blue 6 (6) Gray 1 (1) 3 (3) 1 (1) No. of patients with compliant study 139 (221) 108 (177) 85 (85) No. of patients with noncompliant study 64 (134) 27 (60) 15 (15) Total no. of patients 203 (355) 135 (237) 100 (100) Note. Data in parentheses are numbers of CT examinations performed. No patient was scanned with blue zone protocols during phase 2 or with yellow and blue zone protocols during phase 3. and patient size (weight and transverse diameter) for patients scanned with and those scanned without compliance to the new protocols for different phases of dose reduction were also assessed by using multivariate analysis of variance. Results Patient distribution in individual color zones for individual study phases is summarized in Table 2. Compliance with New Protocols Compared with CT examinations performed in compliance with the new protocol, noncompliant examinations were more often performed in patients who were older, heavier, and larger in size (according to transverse diameter) at all three phases of dose reduction for chest and abdominal CT examinations (P.001). During phase 1, only 58.9% (99 of 168) of chest CT studies and 65.2% (122 of 187) of abdominal CT studies were performed according to the new protocols. In addition, the majority of the noncompliant CT examinations had an inappropriate noise index (32.0% [43 of 134]), tube current range (26.8% [36 of 134]), or combination of voltage, tube current, and noise index (41.0% [55 of 134]). During phase 2, compliance rates for chest and abdominal CT were 76.3% ( radiology.rsnajnls.org Radiology: Volume 252: Number 1 July 2009

6 of 110) and 73.2% (93 of 127), respectively. Most patients who underwent noncompliant examinations were either scanned at different noise indexes (40% [24 of 60]), tube current ranges (53% [32 of 60]), or combinations of voltage, tube current, and noise index (7% [four of 60]). Phase 3 showed a further increase in compliance for chest CT examination to 88% (44 of 50) from 76.3% in phase 2, while abdominal CT examinations compliance increased to 82% (41 of 50) from 73.2% in phase 2. The majority of noncompliant examinations were performed either at different noise indexes (33% [five of 15]), tube current ranges (60% [nine of 15]), or combinations of voltage, tube current, and noise index (7% [one of 15]). Radiation Dose Compared with the noncompliant examinations, there were significant dose reductions for chest and abdominal CT examinations in all phases (P.001). Radiation dose reductions were noted for chest (Table 3) and abdominal (Table 4) CT examinations performed by using all color zones. There also were dose reductions within each weight category. Regardless of the color zone, there was less variability in radiation dose for CT examinations performed with compliance to the protocols than for examinations performed in the weight- and transverse diameter matched patients scanned without compliance to the protocol (P.001). For example, radiation dose for noncompliant CT examinations performed in patients weighing more than 45 kg ranged from 6 to 55 mgy, whereas radiation dose for the corresponding weight group scanned with compliance to the new protocols was 4 18 mgy. Image Quality Detailed image quality and lesion conspicuity scores for chest and abdominal CT are summarized in Table 5. Despite substantial dose reduction with the use of the new protocols for all age groups, both readers gave similar scores for subjective image quality and lesion conspicuity to the compliant and noncompliant CT studies. Both readers rated image noise, visibility of small structures, lesion conspicuity, diagnostic acceptability, and presence and extent of artifacts as acceptable or above average for studies performed in compliance with the new protocols (Figs 2, 3). Discussion Our study shows that high compliance (up to 88% in our department) and substantial dose reduction (up to 89.5% compared with noncompliant CT examinations) can be obtained with pediatric CT protocols based on clinical indications, number of prior CT examinations, and weight-adjusted automatic exposure control. Chest CT studies performed in accordance with Table 3 Radiation Dose and Patient Size for Chest CT Examinations Performed by Using Color Zones in All Phases Parameter No. of Examinations CT Dose Index Volume (mgy) Dose Reduction (%)* Dose-Length Product (mgy cm) Patient Weight (kg) Transverse Diameter (cm) Phase 1 Noncompliant CT Overall compliant CT Pink zone Green zone Gray zone Red zone Phase 2 Noncompliant CT Overall compliant CT Pink zone Green zone Gray zone Red zone Phase 3 Noncompliant CT Overall compliant CT Pink zone Green zone Red zone Note. Unless otherwise indicated, data are means standard deviations. A significant decrease in radiation dose in phase 3 was noted compared with phase 1 for all color zones except for the green and red zones, as larger patients were scanned in phase 3 of these zones (P.001). As noncompliant CT examinations in phase 3 were performed at a lower dose than those in phase 1, relative dose reduction in the red zone was also lower in phase 3 than in phase 1. * Percentage dose reductions for the different color zones are in relation to the noncompliant studies in each phase. No patient was scanned in gray zone in phase 3. Radiology: Volume 252: Number 1 July 2009 radiology.rsnajnls.org 205

7 Table 4 Radiation Dose and Patient Size for Abdominal CT Examinations Performed by Using Color Zones in All Phases Parameter No. of Examinations CT Dose Index Volume (mgy) Dose Reduction (%)* Dose-Length Product (mgy cm) Patient Weight (kg) Transverse Diameter (cm) Phase 1 Noncompliant CT Overall compliant CT Pink zone Green zone Yellow zone Blue zone Red zone Phase 2 Noncompliant CT Overall compliant CT Pink zone Green zone Yellow zone Red zone Phase 3 Noncompliant CT Overall compliant CT Pink zone Green zone Gray zone Red zone Note. Unless otherwise indicated, data are means standard deviations. A significant decrease in radiation dose in phases 2 and 3 was noted compared with that in phase 1 for all color zones. * Percentage dose reduction for the different color zones are in relation to the noncompliant studies in each phase. No patient was scanned in yellow zone for phase 3. Table 5 Modal Subjective Image Quality Scores and Objective Image Noise for Chest and Abdominal CT Examinations Parameter Subjective Image Noise Visibility of Small Structures the new protocols showed an average radiation dose reduction of up to 69.8% in all color zones in the three phases of the study, whereas abdominal CT studies performed with the new protocols showed a 60.6% radiation dose reduction. The color-coded pediatric body CT protocols assessed in our study differ from those described in earlier studies, which primarily described patient size specific protocols by using fixed tube current (4). The new protocols assessed in our study require special attention to the clinical indication, which is the main determinant of radiation dose for each patient. Compliance rates in our study were slightly lower than those reported by Frush et al (4) (97% compliance with their color-coded protocols and 91% compliance with conventional CT protocols). Although technologists were explicitly instructed to use the new protocols saved on the scanners for all children, irrespective of their size and clinical indications, several factors may have contributed to this difference in compliance rate in our study. These factors include the use of more than one scanner (seven multidetector CT scanners) and use of scanners with different detector geometry (eight-, 16-, and 64-section multidetector CT Lesion Conspicuity Diagnostic Acceptability Objective Image Noise* Chest CT Compliant Noncompliant Abdominal CT Compliant Noncompliant Note. There was no significant difference between subjective image quality parameters and objective image noise between compliant and noncompliant CT examinations (P.31.99). * Data are means standard deviations. scanners); there were three separate scanning locations operated by more than 70 full-time and part-time CT technologists who worked in at least three different shifts in our department during the course of our study. It is also possible that 206 radiology.rsnajnls.org Radiology: Volume 252: Number 1 July 2009

8 PEDIATRIC IMAGING: Dose Reduction with New Pediatric CT Protocols some technologists may have accidentally selected adult protocols for scanning some large or older children, without realizing their age. Interestingly, most noncompliant CT examinations did occur in larger and older children. Westra et al (19) have reported that there are considerable variations in the scanning techniques and radiation doses for large children. We believe that this may have also occurred because there was some confusion regarding the cutoff age for pediatric CT. In phase 2, all technologists were again instructed that patients 18 years or younger should be scanned with the new pediatric CT protocols, and additionally, in phase 3, technologists were instructed to scan children weighing more than 100 kg with the newly created weight category. This may have contrib- uted in part to an increase in compliance noted in our study for phase 3 protocols. Another reason for noncompliance in phase 1 and 2 could be lack of consistent guidelines to the technologists on dealing with children who are obese and well above 45 kg. Technologists tended to employ their previous policy of using adult protocols for these patients more often because of concerns that the use of lower Figure 2 Figure 2: Transverse CT images in 16-year-old female adolescent weighing 64 kg who underwent abdominal CT for evaluation of trauma. (a) Noncompliant abdominal CT image (10 mgy, ma, 120 kvp) shows renal laceration (arrow). (b) Follow-up abdominal CT image obtained with the use of green zone and the more than 45 kg category (5.7 mgy, 159 ma, 120 kvp) shows residual left interpolar renal laceration (arrow). Figure 3 Figure 3: Transverse CT images in 6-year-old boy weighing 15 kg who underwent follow-up chest CT for the assessment of stability of pulmonary nodules. (a) Initial CT image obtained with the use of pink zone and the kg category (4.8 mgy, ma, 100 kvp) shows pulmonary nodule in right middle lobe (arrow). (b) Follow-up chest CT image obtained with the use of red zone and the kg category (2 mgy, 99 ma, 100 kvp) demonstrates stable right middle lobe nodule. Radiology: Volume 252: Number 1 July 2009 radiology.rsnajnls.org 207

9 radiation dose with the new protocols would result in noisier CT images. There were limitations to our study. We did not compare the new protocols implemented in our department with previously described color-coded, weight-based, or automatic exposure control based protocols for pediatric radiation dose reduction (4). However, radiation doses observed with the use of the new protocols were well within the reference dose levels described in previous studies from Great Britain (20,21). Radiation dose reductions stated in our study are, however, relative to the doses of scanning protocols used in our institution prior to the implementation of the new protocols. Thus, radiation doses with the new protocols described in our study may be much lower or higher than those based on the existent protocols in other centers. It is therefore important for radiologists, technologists, and CT physicists to employ the concept of structured use of clinical indications, presence of prior CT imaging, body region, and patient weight for dose optimization described in our study rather than use the actual scanning parameters employed in our study, which may or may not be transferable to CT scanners with different detector geometry and from different vendors. Indeed, the intent of this study was to enhance the value of the weight-based techniques for radiation dose optimization in children with information related to the scanning indication, presence of prior imaging, and automatic exposure control techniques. We did not assess the accuracy of the clinical indications for CT scanning as stated by the physician or the accuracy and compliance of radiologists in recommending correct color zones. In conclusion, weight-based protocols for radiation dose reduction in children can be structured to adapt radiation dose to clinical indications, presence of prior CT imaging data for the same indication, and body region while using an automatic exposure control technique. References 1. Linton OW, Mettler FA. National conference on dose reduction in CT, with an emphasis on pediatric patients. AJR Am J Roentgenol 2003;181: Kalra MK, Maher MM, Toth TL, et al. Strategies for CT radiation dose optimization. Radiology 2004;230: One size does not fit all: reducing risks from pediatric CT. ACR Bull 2001;57: Frush DP, Soden B, Frush KS, Lowry C. Improved pediatric multidetector body CT using a size-based color-coded format. AJR Am J Roentgenol 2002;178: Rizzo S, Kalra M, Schmidt B, et al. Comparison of angular and combined automatic tube current modulation techniques with constant tube current CT of the abdomen and pelvis. AJR Am J Roentgenol 2006;186: McCollough CH, Bruesewitz MR, Kofler JM Jr. CT dose reduction and dose management tools: overview of available options. Radio- Graphics 2006;26: Greess H, Nömayr A, Wolf H, et al. Dose reduction in CT examination of children by an attenuation-based on-line modulation of tube current (CARE Dose). Eur Radiol 2002; 12: Kalra MK, Maher MM, D Souza RV, et al. Detection of urinary tract stones at low-radiation-dose CT with z-axis automatic tube current modulation: phantom and clinical studies. Radiology 2005;235: Salamipour H, Jimenez RM, Brec SL, et al. Multidetector row CT in pediatric musculoskeletal imaging. Pediatr Radiol 2005;35: Chapman VM, Kalra M, Halpern E, et al. 16-MDCT of the posttraumatic pediatric elbow: optimum parameters and associated radiation dose. AJR Am J Roentgenol 2005; 185: Udayasankar UK, Braithwaite K, Arvaniti M, et al. Low-dose nonenhanced head CT protocol for follow-up evaluation of children with ventriculoperitoneal shunt: reduction of radiation and effect on image quality. AJNR Am J Neuroradiol 2008;29: de Jong PA, Nakano Y, Lequin MH, Tiddens HA. Dose reduction for CT in children with cystic fibrosis: is it feasible to reduce the number of images per scan? Pediatr Radiol 2006;36: Yi CA, Lee KS, Kim TS, Han D, Sung YM, Kim S. Multidetector CT of bronchiectasis: effect of radiation dose on image quality. AJR Am J Roentgenol 2003;181: Remy-Jardin M, Sobaszek A, Duhamel A, et al. Asbestos-related pleuropulmonary diseases: evaluation with low-dose four-detector row spiral CT. Radiology 2004;233: Gergely I, Neumann C, Reiger F, Dorffner R. Lung nodule detection with ultra-low-dose CT in routine follow-up of cancer patients [in German]. Rofo 2005;177: Kalra MK, Maher MM, Kamath RS, et al. Sixteen-detector row CT of abdomen and pelvis: study for optimization of Z-axis modulation technique performed in 153 patients. Radiology 2004;233: Kalra MK, Maher MM, Toth TL, et al. Comparison of Z-axis automatic tube current modulation technique with fixed tube current CT scanning of abdomen and pelvis. Radiology 2004;232: European guidelines on quality criteria for computed tomography. EUR http: // Accessed April 21, Westra SJ, Kalra MK, Liu B, Buckley V, Ferris T. Radiation exposure of obese children from body CT: are they appropriately treated as adults? Radiological Society of North America /V2007/conference/event_display.cfm?em _id Accessed April 20, Wall BF. Implementation of DRLs in the UK. Radiat Prot Dosimetry 2005;114: Shrimpton PC, Hillier MC, Lewis MA, Dunn M. National survey of doses from CT in the UK: Br J Radiol 2006;79: radiology.rsnajnls.org Radiology: Volume 252: Number 1 July 2009

Radiation Dose Reduction with Hybrid Iterative Reconstruction for Pediatric CT 1

Radiation Dose Reduction with Hybrid Iterative Reconstruction for Pediatric CT 1 Note: This copy is for your personal non-commercial use only. To order presentation-ready copies for distribution to your colleagues or clients, contact us at www.rsna.org/rsnarights. Sarabjeet Singh,

More information

Automatic Patient Centering for MDCT: Effect on Radiation Dose

Automatic Patient Centering for MDCT: Effect on Radiation Dose Patient Centering for MDCT CT Imaging Original Research Jianhai Li 1 Unni K. Udayasankar 1 Thomas L. Toth 2 John Seamans 2 William C. Small 1 Mannudeep K. Kalra 1,3 Li J, Udayasankar UK, Toth TL, Seamans

More information

Studies in both the United States and Europe have revealed that computed tomographic (CT) examinations account for only up to 15% of all imaging exami

Studies in both the United States and Europe have revealed that computed tomographic (CT) examinations account for only up to 15% of all imaging exami Note: This copy is for your personal non-commercial use only. To order presentation-ready copies for distribution to your colleagues or clients, contact us at www.rsna.org/rsnarights. Alice B. Smith, MD

More information

Radiology Rounds A Newsletter for Referring Physicians Massachusetts General Hospital Department of Radiology

Radiology Rounds A Newsletter for Referring Physicians Massachusetts General Hospital Department of Radiology Radiology Rounds A Newsletter for Referring Physicians Massachusetts General Hospital Department of Radiology Minimizing CT Radiation Dose CT examinations improve health care and are an essential part

More information

Acknowledgments. A Specific Diagnostic Task: Lung Nodule Detection. A Specific Diagnostic Task: Chest CT Protocols. Chest CT Protocols

Acknowledgments. A Specific Diagnostic Task: Lung Nodule Detection. A Specific Diagnostic Task: Chest CT Protocols. Chest CT Protocols Personalization of Pediatric Imaging in Terms of Needed Indication-Based Quality Per Dose Acknowledgments Duke University Medical Center Ehsan Samei, PhD Donald Frush, MD Xiang Li PhD DABR Cleveland Clinic

More information

Any imbalance in the production or resorption of CSF results

Any imbalance in the production or resorption of CSF results ORIGINAL RESEARCH U.K. Udayasankar K. Braithwaite M. Arvaniti D. Tudorascu W.C. Small S. Little S. Palasis Low-Dose Nonenhanced Head CT Protocol for Follow-Up Evaluation of Children with Ventriculoperitoneal

More information

How to Develop CT Protocols for Children

How to Develop CT Protocols for Children How to Develop CT Protocols for Children Introduction Prior to 2001 the vast majority of CT imaging of children was conducted using the same or similar techniques used for adult imaging. In 2001, several

More information

ESTABLISHING DRLs in PEDIATRIC CT. Keith Strauss, MSc, FAAPM, FACR Cincinnati Children s Hospital University of Cincinnati College of Medicine

ESTABLISHING DRLs in PEDIATRIC CT. Keith Strauss, MSc, FAAPM, FACR Cincinnati Children s Hospital University of Cincinnati College of Medicine ESTABLISHING DRLs in PEDIATRIC CT Keith Strauss, MSc, FAAPM, FACR Cincinnati Children s Hospital University of Cincinnati College of Medicine CT Dose Indices CTDI INTRODUCTION CTDI 100, CTDI w, CTDI vol

More information

8/1/2017. Financial Disclosures. Dose Tracking at MGH. How Dose Tracking Affected Protocol Optimization in a Tertiary Quaternary Healthcare Center

8/1/2017. Financial Disclosures. Dose Tracking at MGH. How Dose Tracking Affected Protocol Optimization in a Tertiary Quaternary Healthcare Center How Dose Tracking Affected Protocol Optimization in a Tertiary Quaternary Healthcare Center Mannudeep K. Kalra, MD Webster Center for Quality and Safety Massachusetts General Hospital Harvard Medical School

More information

Doses from pediatric CT examinations in Norway Are pediatric scan protocols developed and in daily use?

Doses from pediatric CT examinations in Norway Are pediatric scan protocols developed and in daily use? Doses from pediatric CT examinations in Norway Are pediatric scan protocols developed and in daily use? Eva Godske Friberg * Norwegian Radiation Protection Authority, P.O. Box, Østerås, Norway Abstract.

More information

To Shield or Not to Shield? Lincoln L. Berland, M.D.

To Shield or Not to Shield? Lincoln L. Berland, M.D. To Shield or Not to Shield? Lincoln L. Berland, M.D. Disclosures Consultant to: Nuance, Inc. Page 2 Breast Radiation on CT Use of chest CT has increased in women vulnerable to cancer induction by radiation.

More information

Survey of patients CT radiation dose in Jiangsu Province

Survey of patients CT radiation dose in Jiangsu Province Original Article Page 1 of 6 Survey of patients CT radiation dose in Jiangsu Province Yuanyuan Zhou 1, Chunyong Yang 1, Xingjiang Cao 1, Xiang Du 1, Ningle Yu 1, Xianfeng Zhou 2, Baoli Zhu 1, Jin Wang

More information

How do the Parameters affect Image Quality and Dose for Abdominal CT? Image Review

How do the Parameters affect Image Quality and Dose for Abdominal CT? Image Review How do the Parameters affect Image Quality and Dose for Abdominal CT? Image Review Mannudeep K. Kalra, MD, DNB Massachusetts General Hospital Harvard Medical School Financial Disclosure This presentation

More information

Correlation of Patient Weight and Cross-Sectional Dimensions with Subjective Image Quality at Standard Dose Abdominal CT

Correlation of Patient Weight and Cross-Sectional Dimensions with Subjective Image Quality at Standard Dose Abdominal CT Correlation of Patient Weight and Cross-Sectional Dimensions with Subjective Image Quality at Standard Dose Abdominal CT Mannudeep K. Kalra, MD, DNB Michael M. Maher, MD, FRCR, FFR (RCSI) Srinivasa R.

More information

Managing Radiation Risk in Pediatric CT Imaging

Managing Radiation Risk in Pediatric CT Imaging Managing Radiation Risk in Pediatric CT Imaging Mahadevappa Mahesh, MS, PhD, FAAPM, FACR, FACMP, FSCCT. Professor of Radiology and Cardiology Johns Hopkins University School of Medicine Chief Physicist

More information

Introduction and Background

Introduction and Background CT Lung Cancer Screening and the Medical Physicist: Background, Findings and Participant Dosimetry Summary of the National Lung Screening Trial (NLST) Randell Kruger, PhD, DABR Medical Physics Section

More information

Radiation Dose Reduction: Should You Use a Bismuth Breast Shield?

Radiation Dose Reduction: Should You Use a Bismuth Breast Shield? Radiation Dose Reduction: Should You Use a Bismuth Breast Shield? Lincoln L. Berland, M.D., F.A.C.R. Michael V. Yester, Ph.D. University of Alabama at Birmingham Breast Radiation on CT Use of chest CT

More information

Dose to Radiosensitive Organs During Routine Chest CT: Effects of Tube Current Modulation

Dose to Radiosensitive Organs During Routine Chest CT: Effects of Tube Current Modulation Medical Physics and Informatics Original Research Angel et al. Radiation Dose During Chest CT Medical Physics and Informatics Original Research Erin Angel 1,2 Nazanin Yaghmai 1 Cecilia Matilda Jude 1 John

More information

Pediatric chest HRCT using the idose 4 Hybrid Iterative Reconstruction Algorithm: Which idose level to choose?

Pediatric chest HRCT using the idose 4 Hybrid Iterative Reconstruction Algorithm: Which idose level to choose? Journal of Physics: Conference Series PAPER OPEN ACCESS Pediatric chest HRCT using the idose 4 Hybrid Iterative Reconstruction Algorithm: Which idose level to choose? To cite this article: M Smarda et

More information

Optimizing radiation dose by varying age at pediatric temporal bone CT

Optimizing radiation dose by varying age at pediatric temporal bone CT JOURNAL OF APPLIED CLINICAL MEDICAL PHYSICS, VOLUME 16, NUMBER 1, 2015 Optimizing radiation dose by varying age at pediatric temporal bone CT Daichi Noto, 1 Yoshinori Funama, 2a Mika Kitajima, 3 Daisuke

More information

Radiography/Radiology

Radiography/Radiology Radiography/Radiology Activity for 2017 Activity No: A1(17) Topic CT radiation Article CT radiation: key concepts for gentle and wise use Approved for (3) Clinical Continuing Educational Units (CEU s)

More information

CT Dose Reduction in Pediatric Patients

CT Dose Reduction in Pediatric Patients CT Dose Reduction in Pediatric Patients By Kelly Firestine, RT(R)(CT)(M) Executive Summary CT is an incredibly valuable imaging tool, but there are unique concerns with pediatric patients, including the

More information

Ask EuroSafe Imaging. Tips & Tricks. CT Working Group. Optimization of scan length to reduce CT radiation dose

Ask EuroSafe Imaging. Tips & Tricks. CT Working Group. Optimization of scan length to reduce CT radiation dose Ask EuroSafe Imaging Tips & Tricks CT Working Group Optimization of scan length to reduce CT radiation dose Alban Gervaise (Centre Hospitalier Universitaire Nancy, FR) Mika Kortesniemi (HUS Medical Imaging

More information

Implementation of the 2012 ACR CT QC Manual in a Community Hospital Setting BRUCE E. HASSELQUIST, PH.D., DABR, DABSNM ASPIRUS WAUSAU HOSPITAL

Implementation of the 2012 ACR CT QC Manual in a Community Hospital Setting BRUCE E. HASSELQUIST, PH.D., DABR, DABSNM ASPIRUS WAUSAU HOSPITAL Implementation of the 2012 ACR CT QC Manual in a Community Hospital Setting BRUCE E. HASSELQUIST, PH.D., DABR, DABSNM ASPIRUS WAUSAU HOSPITAL Conflict of Interest Disclaimer Employee of Aspirus Wausau

More information

Medical Physics and Informatics Original Research

Medical Physics and Informatics Original Research Medical Physics and Informatics Original Research Sagara et al. Abdominal CT With Low Versus Routine Dose Medical Physics and Informatics Original Research Yoshiko Sagara 1 Amy K. Hara 2 William Pavlicek

More information

Ask EuroSafe Imaging. Tips & Tricks. Paediatric Imaging Working Group. Shielding in pediatric CT

Ask EuroSafe Imaging. Tips & Tricks. Paediatric Imaging Working Group. Shielding in pediatric CT Ask EuroSafe Imaging Tips & Tricks Paediatric Imaging Working Group Shielding in pediatric CT Claudio Granata (IRCCS Istituto Giannina Gaslini, IT) Joana Santos (ESTeSC-Coimbra Health School, PT) Elina

More information

B. CT protocols for the spine

B. CT protocols for the spine B. CT protocols for the spine Poster No.: A-003 Congress: ECR 2010 Type: Invited Speaker Topic: Neuro Authors: B. Tins; Oswestry/UK Keywords: CT, spine, diagnostic imaging protocol DOI: 10.1594/ecr2010/A-003

More information

SPECIFIC PRINCIPLES FOR DOSE REDUCTION IN HEAD CT IMAGING. Rajiv Gupta, MD, PhD Neuroradiology, Massachusetts General Hospital Harvard Medical School

SPECIFIC PRINCIPLES FOR DOSE REDUCTION IN HEAD CT IMAGING. Rajiv Gupta, MD, PhD Neuroradiology, Massachusetts General Hospital Harvard Medical School SPECIFIC PRINCIPLES FOR DOSE REDUCTION IN HEAD CT IMAGING Rajiv Gupta, MD, PhD Neuroradiology, Massachusetts General Hospital Harvard Medical School OUTLINE 1 st Presentation: Dose optimization strategies

More information

CT Quality Control Manual FAQs

CT Quality Control Manual FAQs CT Quality Control Manual FAQs General Question: How often will the QC Manual be updated and how will those updates be communicated? Answer: The ACR CT Physics Subcommittee will review any comments, issues

More information

Journal of Radiology and Imaging

Journal of Radiology and Imaging Journal of Radiology and Imaging An Open Access Publisher http://dx.doi.org/10.14312/2399-8172.2017-2 Original research Open Access Reduction of radiation dose in adult CT-guided musculoskeletal procedures

More information

CT angiography of pulmonary arteries to detect pulmonary embolism with low kv settings

CT angiography of pulmonary arteries to detect pulmonary embolism with low kv settings CT angiography of pulmonary arteries to detect pulmonary embolism with low kv settings Poster No.: C-3289 Congress: ECR 2010 Type: Scientific Exhibit Topic: Chest - Your latest results Authors: M. K. Gill,

More information

A more accurate method to estimate patient dose during body CT examinations with tube current modulation

A more accurate method to estimate patient dose during body CT examinations with tube current modulation A more accurate method to estimate patient dose during body CT examinations with tube current modulation Poster No.: C-0738 Congress: ECR 2014 Type: Scientific Exhibit Authors: A. Kawaguchi 1, Y. Matsunaga

More information

X-Ray & CT Physics / Clinical CT

X-Ray & CT Physics / Clinical CT Computed Tomography-Basic Principles and Good Practice X-Ray & CT Physics / Clinical CT INSTRUCTORS: Dane Franklin, MBA, RT (R) (CT) Office hours will be Tuesdays from 5pm to 6pm CLASSROOM: TIME: REQUIRED

More information

8/18/2011. Acknowledgements. Managing Pediatric CT Patient Doses INTRODUCTION

8/18/2011. Acknowledgements. Managing Pediatric CT Patient Doses INTRODUCTION Managing Pediatric CT Patient Doses Keith J. Strauss, MSc, FAAPM, FACR President X-Ray Computations, Inc. Boston, Massachusetts Acknowledgements Marilyn Goske, MD John Boone, PhD Cynthia McCollough, PhD

More information

Application of CARE kv and SAFIRE in Contrast-Enhanced CT Examination on Thorax

Application of CARE kv and SAFIRE in Contrast-Enhanced CT Examination on Thorax Application of CARE kv and SAFIRE in Contrast-Enhanced CT Examination on Thorax Poster No.: C-0013 Congress: ECR 2013 Type: Authors: Scientific Exhibit Z. Dejian 1, X. Zhuodong 2, J. Hui 2, L. Xiao 3 ;

More information

Conventional and spiral CT dose indices in Yazd general hospitals, Iran

Conventional and spiral CT dose indices in Yazd general hospitals, Iran Iran. J. Radiat. Res., 2006; 3 (4): 183-189 Conventional and spiral CT dose indices in Yazd general hospitals, Iran F. Bouzarjomehri 1*,M.H.Zare 2, D. Shahbazi 2 1 Department of Medical Physics, Shahid

More information

Ultralow Dose Chest CT with MBIR

Ultralow Dose Chest CT with MBIR Ultralow Dose Chest CT with MBIR Ella A. Kazerooni, M.D. Professor & Director Cardiothoracic Radiology Associate Chair for Clinical Affairs University of Michigan Disclosures Consultant: GE Healthcare

More information

Recent technical advances have greatly increased the clinical

Recent technical advances have greatly increased the clinical ORIGINAL RESEARCH E.J. Lee S.K. Lee R. Agid P. Howard J.M. Bae K. terbrugge Comparison of Image Quality and Radiation Dose between Fixed Tube Current and Combined Automatic Tube Current Modulation in Craniocervical

More information

Dual-Energy CT: The Technological Approaches

Dual-Energy CT: The Technological Approaches Dual-Energy CT: The Technological Approaches Dushyant Sahani, M.D Director of CT Associate Professor of Radiology Massachusetts General Hospital Harvard Medical School Email-dsahani@partners.org Disclosure

More information

What Have We Learned from Children? Donald P. Frush, MD

What Have We Learned from Children? Donald P. Frush, MD What Have We Learned from Children? Donald P. Frush, MD Medical Radiation and Children: Accomplishments We can lower doses (read noisier exams) We should lower doses Multiphase exams should be justified

More information

CURRENT CT DOSE METRICS: MAKING CTDI SIZE-SPECIFIC

CURRENT CT DOSE METRICS: MAKING CTDI SIZE-SPECIFIC CURRENT CT DOSE METRICS: MAKING CTDI SIZE-SPECIFIC Keith Strauss, MSc, FAAPM, FACR Cincinnati Children s Hospital University of Cincinnati College of Medicine Acknowledgments John Boone, PhD Michael McNitt-Grey,

More information

BrightSpeed Elite CT with ASiR: Comparing Dose & Image Quality Rule Out Pulmonary Embolism on Initial & Follow-Up Exam

BrightSpeed Elite CT with ASiR: Comparing Dose & Image Quality Rule Out Pulmonary Embolism on Initial & Follow-Up Exam GE Healthcare BrightSpeed Elite CT with ASiR: Comparing Dose & Image Quality Rule Out Pulmonary Embolism on Initial & Follow-Up Exam Michael Swack, MD Diagnostic Radiologist Irvington Radiologists, PC

More information

Medical Diagnostic Imaging

Medical Diagnostic Imaging Medical Diagnostic Imaging Laboratories Medical Diagnostic Imaging Lab Name Location Person in Charge Programs Served Courses Served Patient Care and Management (2) Introduction to MDI Radiographic Technique

More information

Outcomes in the NLST. Health system infrastructure needs to implement screening

Outcomes in the NLST. Health system infrastructure needs to implement screening Outcomes in the NLST Health system infrastructure needs to implement screening Denise R. Aberle, MD Professor of Radiology and Bioengineering David Geffen School of Medicine at UCLA 1 Disclosures I have

More information

Debra Pennington, MD Director of Imaging Dell Children s Medical Center

Debra Pennington, MD Director of Imaging Dell Children s Medical Center Debra Pennington, MD Director of Imaging Dell Children s Medical Center 1 Gray (Gy) is 1 J of radiation energy/ 1 kg matter (physical quantity absorbed dose) Diagnostic imaging doses in mgy (.001 Gy)

More information

Dual Energy CT Aortography: Can We Reduce Iodine Dose??

Dual Energy CT Aortography: Can We Reduce Iodine Dose?? Dual Energy CT Aortography: Can We Reduce Iodine Dose?? William P. Shuman MD, FACR FSCBTMR Department of Radiology University of Washington SCBTMR Annual Course Boston, October 10, 2012 Conflict of Interest

More information

Accounting for Imaging Dose

Accounting for Imaging Dose Accounting for Imaging Dose High Profile Over-exposures Lead to Growing Concern FDA issues warning in October 2009-209 patients exposed to 8 times typical dose for CT brain perfusion scan (3-4 Gy) - Some

More information

Organ-based Tube Current Modulation: Are Women s Breasts Positioned in the Reduced-Dose Zone? 1

Organ-based Tube Current Modulation: Are Women s Breasts Positioned in the Reduced-Dose Zone? 1 Note: This copy is for your personal non-commercial use only. To order presentation-ready copies for distribution to your colleagues or clients, contact us at www.rsna.org/rsnarights. Original Research

More information

CT Dose Optimization for Whole- Body PET/CT Examinations

CT Dose Optimization for Whole- Body PET/CT Examinations Nuclear Medicine and Molecular Imaging Original Research Tonkopi et al. CT Dose Optimization for PET/CT Nuclear Medicine and Molecular Imaging Original Research FOCUS ON: Elena Tonkopi 1,2 Andrew A. Ross

More information

Toshiba Aquillion 64 CT Scanner. Phantom Center Periphery Center Periphery Center Periphery

Toshiba Aquillion 64 CT Scanner. Phantom Center Periphery Center Periphery Center Periphery Comparison of radiation dose and imaging performance for the standard Varian x-ray tube and the Richardson Healthcare ALTA750 replacement tube for the Toshiba Aquillion CT scanners. by Robert L. Dixon,

More information

Original Article Thoracic Imaging

Original Article Thoracic Imaging Original Article Thoracic Imaging https://doi.org/10.3348/kjr.2018.19.6.1179 pissn 1229-6929 eissn 2005-8330 Korean J Radiol 2018;19(6):1179-1186 Size-Specific Dose Estimation In the Korean Lung Cancer

More information

CT dose survey data acquisition form

CT dose survey data acquisition form CT dose survey data acquisition form CT Protocol page CT Head (acute stroke) C-spine (fracture) Chest (lung cancer) Chest High-Res. (interstitial lung disease) CTA (blood vessels) CTPA (PE) Abdomen (liver

More information

Low-dose CT Lung Cancer Screening Guidelines for Pulmonary Nodules Management Version 2

Low-dose CT Lung Cancer Screening Guidelines for Pulmonary Nodules Management Version 2 Low-dose CT Lung Cancer Screening Guidelines for Pulmonary Nodules Management Version 2 The Committee for Management of CT-screening-detected Pulmonary Nodules 2009-2011 The Japanese Society of CT Screening

More information

Estimated Radiation Dose Associated With Low-Dose Chest CT of Average-Size Participants in the National Lung Screening Trial

Estimated Radiation Dose Associated With Low-Dose Chest CT of Average-Size Participants in the National Lung Screening Trial Medical Physics and Informatics Original Research Larke et al. Estimated Radiation Dose for Low-Dose Chest CT Medical Physics and Informatics Original Research Frederick J. Larke 1 Randell L. Kruger 2

More information

State of the art and future development for standardized estimation of organ doses in CT

State of the art and future development for standardized estimation of organ doses in CT State of the art and future development for standardized estimation of organ doses in CT March 2015 William J. O Connel, Dr. Ph, Senior Medical Physicist Imagination at work. Agenda Introduction Duke Florida

More information

CT of the chest with model-based, fully iterative reconstruction: comparison with adaptive statistical iterative reconstruction

CT of the chest with model-based, fully iterative reconstruction: comparison with adaptive statistical iterative reconstruction Ichikawa et al. BMC Medical Imaging 2013, 13:27 RESEARCH ARTICLE Open Access CT of the chest with model-based, fully iterative reconstruction: comparison with adaptive statistical iterative reconstruction

More information

An Assessment of Organ and Effective Dose of Patients who Undertake CT Examinations in two Teaching Hospitals of Mashhad&Isfahan

An Assessment of Organ and Effective Dose of Patients who Undertake CT Examinations in two Teaching Hospitals of Mashhad&Isfahan An Assessment of Organ and Effective Dose of Patients who Undertake CT Examinations in two Teaching Hospitals of Mashhad&Isfahan *M.T.Bahreyni Toossi, **S.Mohandes Dastgherdi Medical Physics Dep., Faculty

More information

CT Optimisation for Paediatric SPECT/CT Examinations. Sarah Bell

CT Optimisation for Paediatric SPECT/CT Examinations. Sarah Bell CT Optimisation for Paediatric SPECT/CT Examinations Sarah Bell Sarah.bell14@nhs.net Outline 1. Introduction 2. Aims and Objectives 3. Methods 4. Results 5. Discussion 6. Conclusions 7. References Introduction

More information

AMERICAN COLLEGE OF SURGEONS CRITICAL CARE REVIEW COURSE 2012 HOT TOPICS IN PEDIATRIC CRITICAL CARE

AMERICAN COLLEGE OF SURGEONS CRITICAL CARE REVIEW COURSE 2012 HOT TOPICS IN PEDIATRIC CRITICAL CARE AMERICAN COLLEGE OF SURGEONS CRITICAL CARE REVIEW COURSE 2012 HOT TOPICS IN PEDIATRIC CRITICAL CARE Karyn L. Butler, MD, FACS, FCCM Chief, Surgical Critical Care Hartford Hospital / University of Connecticut

More information

Computed tomography Acceptance testing and dose measurements

Computed tomography Acceptance testing and dose measurements Computed tomography Acceptance testing and dose measurements Jonas Andersson Medical Physicist, Ph.D. Department of Radiation Sciences University Hospital of Norrland, Umeå Sweden Contents The Computed

More information

Imaging Features of Acute Pyelonephritis in Contrast Computed Tomography as Predictors of Need for Intervention

Imaging Features of Acute Pyelonephritis in Contrast Computed Tomography as Predictors of Need for Intervention Imaging Features of Acute Pyelonephritis in Contrast Computed Tomography as Predictors of Need for Intervention Poster No.: C-0088 Congress: ECR 2014 Type: Scientific Exhibit Authors: C. Y. Lee, C. W.

More information

Imaging Features of Acute Pyelonephritis in Contrast Computed Tomography as Predictors of Need for Intervention

Imaging Features of Acute Pyelonephritis in Contrast Computed Tomography as Predictors of Need for Intervention Imaging Features of Acute Pyelonephritis in Contrast Computed Tomography as Predictors of Need for Intervention Poster No.: C-0088 Congress: ECR 2014 Type: Scientific Exhibit Authors: C. Y. Lee, C. W.

More information

Original Article INTRODUCTION

Original Article INTRODUCTION Original Article http://dx.doi.org/10.3348/kjr.2012.13.6.720 pissn 1229-6929 eissn 2005-8330 Korean J Radiol 2012;13(6):720-727 Radiation Dose Reduction of Chest CT with Iterative Reconstruction in Image

More information

Scientific Exhibit. Authors: D. Takenaka, Y. Ohno, Y. Onishi, K. Matsumoto, T.

Scientific Exhibit. Authors: D. Takenaka, Y. Ohno, Y. Onishi, K. Matsumoto, T. The feasibility of biphasic contrast-media-injection-protocol for chest imaging on 320-slice volume MDCT: Direct comparison of biphasic and bolus contrast-media injection protocols on 320-slice volume

More information

CT Versus MR for the Runoff

CT Versus MR for the Runoff CT Versus MR for the Runoff Robert R. Edelman, M.D. Dept. of Radiology NorthShore University HealthSystem Feinberg School of Medicine, Northwestern University Magnetic Resonance Computed Tomography Radio

More information

Translating Protocols Across Patient Size: Babies to Bariatric

Translating Protocols Across Patient Size: Babies to Bariatric Translating Protocols Across Patient Size: Babies to Bariatric Cynthia H. McCollough, PhD, FACR, FAAPM Professor of Radiologic Physics Director, CT Clinical Innovation Center Department of Radiology Mayo

More information

Organ-Based Dose Current Modulation and Thyroid Shields: Techniques of Radiation Dose Reduction for Neck CT

Organ-Based Dose Current Modulation and Thyroid Shields: Techniques of Radiation Dose Reduction for Neck CT Medical Physics and Informatics Original Research Hoang et al. Radiation Dose Reduction for Neck CT Medical Physics and Informatics Original Research Jenny K. Hoang 1,2 Terry T. Yoshizumi 1 Kingshuk Roy

More information

Preparing for Medical Physics Components of the ABR Core Examination

Preparing for Medical Physics Components of the ABR Core Examination Preparing for Medical Physics Components of the ABR Core Examination The ABR core examination for radiologists contains material on medical physics. This content is based on the medical physics that is

More information

Cumulative radiation CT dose in young traumatic patients: a single centre 5 years retrospective review

Cumulative radiation CT dose in young traumatic patients: a single centre 5 years retrospective review Cumulative radiation CT dose in young traumatic patients: a single centre 5 years retrospective review Poster No.: C-1604 Congress: ECR 2014 Type: Scientific Exhibit Authors: S. Salerno, C. Geraci, E.

More information

Guidelines for the Management of Pulmonary Nodules Detected by Low-dose CT Lung Cancer Screening

Guidelines for the Management of Pulmonary Nodules Detected by Low-dose CT Lung Cancer Screening Guidelines for the Management of Pulmonary Nodules Detected by Low-dose CT Lung Cancer Screening 1. Introduction In January 2005, the Committee for Preparation of Clinical Practice Guidelines for the Management

More information

Cardiopulmonary Imaging Original Research

Cardiopulmonary Imaging Original Research Cardiopulmonary Imaging Original Research Vardhanabhuti et al. Three Algorithms to Assess Standard- and Low-Dose Chest CT Cardiopulmonary Imaging Original Research FOCUS ON: Varut Vardhanabhuti 1,2 Robert

More information

CT examination is a high-radiation-dose imaging technique

CT examination is a high-radiation-dose imaging technique ORIGINAL RESEARCH J.S.P. Tan K.-L. Tan J.C.L. Lee C.-M. Wan J.-L. Leong L.-L. Chan Comparison of Eye Lens Dose on Neuroimaging Protocols between 16- and 64-Section Multidetector CT: Achieving the Lowest

More information

Digital tomosynthesis (DT) has been well described as a

Digital tomosynthesis (DT) has been well described as a Case Report The Usefulness of Digital Tomosynthesis (DT) in Assisting in Cases of Doubtful Routine Radiography and/or Computed Tomography (CT) Image. Abstract Digital tomosynthesis is useful in assisting

More information

Ultra-low dose CT of the acute abdomen: Spectrum of imaging findings

Ultra-low dose CT of the acute abdomen: Spectrum of imaging findings Ultra-low dose CT of the acute abdomen: Spectrum of imaging findings Poster No.: C-1452 Congress: ECR 2010 Type: Educational Exhibit Topic: GI Tract Authors: P. A. Vlachou, C. Kloeters, S. Kandel, P. Hein,

More information

At present, CT of the brain is the imaging technique of choice

At present, CT of the brain is the imaging technique of choice ORIGINAL RESEARCH PATIENT SAFETY Acute Intracranial Hemorrhage in CT: Benefits of Sinogram-Affirmed Iterative Reconstruction Techniques B. Bodelle, E. Klein, N.N.N. Naguib, R.W. Bauer, J.M. Kerl, F. Al-Butmeh,

More information

Methods of Counting Ribs on Chest CT: The Modified Sternomanubrial Approach 1

Methods of Counting Ribs on Chest CT: The Modified Sternomanubrial Approach 1 Methods of Counting Ribs on Chest CT: The Modified Sternomanubrial Approach 1 Kyung Sik Yi, M.D., Sung Jin Kim, M.D., Min Hee Jeon, M.D., Seung Young Lee, M.D., Il Hun Bae, M.D. Purpose: The purpose of

More information

Ask EuroSafe Imaging. Tips & Tricks. CT Working Group

Ask EuroSafe Imaging. Tips & Tricks. CT Working Group Ask EuroSafe Imaging Tips & Tricks CT Working Group The use of bi-phase injection protocols to reduce the number of acquisition phases and radiation dose Alban Gervaise (Medical Imaging Department, HIA

More information

Dianna Cody, PhD, DABR, FAAPM Professor & Clinical Operations Director Imaging Physics U.T. M.D. Anderson Cancer Center Houston, TX

Dianna Cody, PhD, DABR, FAAPM Professor & Clinical Operations Director Imaging Physics U.T. M.D. Anderson Cancer Center Houston, TX Dianna Cody, PhD, DABR, FAAPM Professor & Clinical Operations Director Imaging Physics U.T. M.D. Anderson Cancer Center Houston, TX Learning Objectives: Limitations for estimating patient dose for CT Methods

More information

Summary and conclusions

Summary and conclusions Summary and conclusions 7 Chapter 7 68 Summary and conclusions Chapter 1 provides a general introduction to this thesis focused on the use of ultrasound (US) in children with abdominal problems. The literature

More information

Radiation Dosimetry for CT Protocols

Radiation Dosimetry for CT Protocols Radiation Dosimetry for CT Protocols This document contains radiation dosimetry information from CT scans and can be used by investigators to estimate the dosimetry information required by the JRSC or

More information

Web Chapter 3. Image Gallery: Lesion detection on low dose chest CT

Web Chapter 3. Image Gallery: Lesion detection on low dose chest CT Web Chapter 3 Image Gallery: Lesion detection on low dose chest CT Sarabjeet Singh, MD Mannudeep K. Kalra, MD *Eugene J. Mark, MD *James Stone, MD James H. Thrall, MD Department of Radiology and *Department

More information

Combined Anatomical and Functional Imaging with Revolution * CT

Combined Anatomical and Functional Imaging with Revolution * CT GE Healthcare Case studies Combined Anatomical and Functional Imaging with Revolution * CT Jean-Louis Sablayrolles, M.D. Centre Cardiologique du Nord, Saint-Denis, France Case 1 Whole Brain Perfusion and

More information

Improvement of Image Quality with ß-Blocker Premedication on ECG-Gated 16-MDCT Coronary Angiography

Improvement of Image Quality with ß-Blocker Premedication on ECG-Gated 16-MDCT Coronary Angiography 16-MDCT Coronary Angiography Shim et al. 16-MDCT Coronary Angiography Sung Shine Shim 1 Yookyung Kim Soo Mee Lim Received December 1, 2003; accepted after revision June 1, 2004. 1 All authors: Department

More information

Pediatric 16-slice CT Protocols:

Pediatric 16-slice CT Protocols: Pediatric 16-slice CT Protocols: Radiation Dose and Image Quality 1 Dong Hyun Yang, M.D., Hyun Woo Goo, M.D. Purpose: To assess radiation dose and image quality of our pediatric 16-slice CT protocols and

More information

Gemstone Spectral Imaging quantifies lesion characteristics for a confident diagnosis

Gemstone Spectral Imaging quantifies lesion characteristics for a confident diagnosis GE Healthcare Gemstone Spectral Imaging quantifies lesion characteristics for a confident diagnosis CT clinical case study lesion characterization Desiree Morgan, MD Vice Chair of Clinical Research Professor

More information

Low Dose Era in Cardiac CT

Low Dose Era in Cardiac CT Low Dose Era in Cardiac CT DIANA E. LITMANOVICH, MD Department of Radiology Beth Israel Deaconess Medical Center Harvard Medical School Disclosures Neither I nor my immediate family members have a financial

More information

Fetal Dose Calculations and Impact on Patient Care

Fetal Dose Calculations and Impact on Patient Care Fetal Dose Calculations and Impact on Patient Care Matt Hough, MS, DABR, DABMP Florida Hospital Diagnostic Medical Physics and Radiation Safety Resource ACR-SPR Practice Parameter for Imaging Pregnant

More information

Electronic collimation and radiation protection in paediatric digital radiography: revival of the silver lining

Electronic collimation and radiation protection in paediatric digital radiography: revival of the silver lining Insights Imaging (2013) 4:723 727 DOI 10.1007/s13244-013-0281-5 PICTORIAL REVIEW Electronic collimation and radiation protection in paediatric digital radiography: revival of the silver lining J. Bomer

More information

CT Head Dose Reduction Using Spiral Scanning Protocol

CT Head Dose Reduction Using Spiral Scanning Protocol CT Head Dose Reduction Using Spiral Scanning Protocol Reed, William J MD; Broderick, Daniel F, MD; Weindling, Steven M, MD; Czervionke, Leo F MD; and Morin, Richard L; PhD; Mayo Clinic, Department of Radiology;

More information

Reduced exposure using asymmetric cone beam processing for wide area detector cardiac CT

Reduced exposure using asymmetric cone beam processing for wide area detector cardiac CT Reduced exposure using asymmetric cone beam processing for wide area detector cardiac CT The Harvard community has made this article openly available. Please share how this access benefits you. Your story

More information

Scientific Exhibit Authors:

Scientific Exhibit Authors: Clinical Audit on Optimization of Radiation Dose from MDCT: Effect on Diagnostic Reference Levels for Brain, Sinus, Cervical Spine, Chest, Abdomen-Pelvis, and Lumbar Spine Examinations and on Nationwide

More information

Conventional High-Resolution CT Versus Helical High- Resolution MDCT in the Detection of Bronchiectasis

Conventional High-Resolution CT Versus Helical High- Resolution MDCT in the Detection of Bronchiectasis High- Resolution CT Versus MDCT in Detecting Bronchiectas is Chest Imaging Original Research A C M E D E N T U R I C A L I M A G I N G AJR 2006; 187:414 420 0361 803X/06/1872 414 American Roentgen Ray

More information

Computed Tomography (CT) - Chest

Computed Tomography (CT) - Chest Scan for mobile link. Computed Tomography (CT) - Chest Computed tomography (CT) of the chest uses special x-ray equipment to examine abnormalities found in other imaging tests and to help diagnose the

More information

Doses from Cervical Spine Computed Tomography (CT) examinations in the UK. John Holroyd and Sue Edyvean

Doses from Cervical Spine Computed Tomography (CT) examinations in the UK. John Holroyd and Sue Edyvean Doses from Cervical Spine Computed Tomography (CT) examinations in the UK John Holroyd and Sue Edyvean Why a new dose survey? Number of enquires received concerning the current NDRL Concern that could

More information

Gastrointestinal Imaging Original Research

Gastrointestinal Imaging Original Research Gastrointestinal Imaging Original Research MDCT Enterography in Crohn s Disease Gastrointestinal Imaging Original Research FOCUS ON: Brian C. Allen 1 Mark E. Baker 1 David M. Einstein 1 Erick M. Remer

More information

Seattle Children s Hospital Radiology Department. Statement regarding radiation exposure related to computed. tomography (CT) exams

Seattle Children s Hospital Radiology Department. Statement regarding radiation exposure related to computed. tomography (CT) exams Seattle Children s Hospital Radiology Department Statement regarding radiation exposure related to computed tomography (CT) exams Computed tomography (CT) scanners use radiation in the form of X- rays

More information

Optimization of kvp and mas for Pediatric Low-Dose Simulated Abdominal CT: Is It Best to Base Parameter Selection on Object Circumference?

Optimization of kvp and mas for Pediatric Low-Dose Simulated Abdominal CT: Is It Best to Base Parameter Selection on Object Circumference? Pediatric Imaging Original Research Reid et al. Parameter Selection for Pediatric Abdominal CT Downloaded from www.ajronline.org by 46.3.3.24 on 2/3/18 from IP address 46.3.3.24. Copyright ARRS. For personal

More information

HONG KONG COLLEGE OF RADIOLOGISTS. Higher Training (Radiology) Subspecialty Training in Computed Tomography

HONG KONG COLLEGE OF RADIOLOGISTS. Higher Training (Radiology) Subspecialty Training in Computed Tomography HONG KONG COLLEGE OF RADIOLOGISTS Higher Training (Radiology) Subspecialty Training in Computed Tomography [The following guidelines should be read in conjunction with the General Guidelines on Higher

More information

Use of IV-contrast versus IV-and oral-contrast in the evaluation of abdominal pain on CT in the emergency department

Use of IV-contrast versus IV-and oral-contrast in the evaluation of abdominal pain on CT in the emergency department Use of IV-contrast versus IV-and oral-contrast in the evaluation of abdominal pain on CT in the emergency department Poster No.: B-0693 Congress: ECR 2016 Type: Authors: Scientific Paper M. Wasserman 1,

More information