Appendix Sample CT Protocols

Transcription

1 Appendix Sample CT Protocols The protocols in the following Appendix are designed to serve as a general guide to setting up comprehensive CT protocols on your scanner. The protocols are independent of manufacturer; therefore they are not optimized for any individual scanner or patient and will generally require some modification before actual use. Some information such as specific reconstruction filters and algorithms is very manufacturer specific and cannot be included. This is also not meant to be a completely exhaustive list of protocols. Many specialty protocols for specific indications can be modified from the base protocols and created on the scanner. The protocols are optimized for 16-detector scanners. Modification for 4- or 8-slice scanners will require changes primarily in acquisition slice thickness but may also affect contrast dose and timing and reconstructed image thickness. The Appendix is divided into two sections. Appendix A contains general protocols for neuro, body and musculoskeletal imaging and Appendix B contains protocols for CT angiography. These protocols are designed for adult patients. Special Note Regarding Pediatric CT Protocols Pediatric patients require more attention than adults. In each case, the protocols need to be tailored to the individual patient, and special attention must be made to ensure that radiation dose is minimized. Pediatric patients, because of their smaller size, can generally be scanned at the thinnest slice thickness option available on a 16- detector scanner for almost every exam. If a 4-slice scanner is used, then submillimeter slice thickness should be used judiciously because of the increased radiation dose provided. Also, unlike adult patients, routine multiphase protocols should be avoided. Multiphase scanning should be employed only when truly needed for diagnosis in specific cases. Higher pitch values of and short rotation times are both useful 291

2 292 Appendix: Sample CT Protocols techniques to increase the speed of the scan and to reduce motion artifacts as well as radiation dose. Radiation dose parameters for pediatric CT patients must be carefully adjusted for body size and weight. Fortunately, the technologist can use advanced automated exposure control (AEC) software on the scanner to make many of these decisions automatically. If this software is not available, then a reference chart (Table A1) should be used to determine the appropriate mas for weight. The kv should also be adjusted for children with 80 kv 100 kv used in smaller children (<50kg) and 100kV 120kV used in larger children (>50kg). Even when AEC software is used, the parameters set for the scan should undergo a reality check to make sure they fall within the expected range. Contrast administration for pediatric patients can be more challenging than for adults because of the limited venous access. The standard contrast dose for pediatric patients is determined by weight and for most exams a contrast dose of 2mL/kg is adequate. The contrast injection can be performed either manually or by power injector. Power injection is preferred but is often not possible. Peripheral small IVs, butterfly needles and central lines are usually injected manually. ning can begin at a predetermined delay (30 50 seconds for head, chest and abdomen scans depending on size) or started once all the contrast is in. If the manual injection is rapid, an additional delay may be needed before starting the scan (10 20 seconds). CTA is best performed with a power injector, as this will routinely produce more uniform and denser vascular enhancement. Attempts should be made to place an angiocath into an antecubital vein. A 22- gauge catheter can be injected at 2 3 ml/sec and a 24-gauge catheter at 1.2 ml/sec. Delay will vary depending on injection rate; therefore, it is best to use bolus-triggering techniques to initiate the scan. If it is not possible to use a power injector, successful CTA can still be performed with a rapid manual injection. Table A1. Recommended Dose Parameters for Pediatric Body MDCT Dose Parameters Patient Weight (kg) kv mas Chest mas Abdomen < >

3 Appendix: Sample CT Protocols 293 General Prolocols Parameters Skull Base to Vertex Helical or Sequence No sec 240mm 1 to 1.5mm 1 Optional cc 25 to 50cc 2cc/sec No Yes 70 sec Head Routine Head no same3-5mm No No Parameters Skull Base to Vertex Helical No 0.5 sec 240mm.5 to.75mm 1 Optional cc 25 to 50cc 2cc/sec No Yes 70 sec Head High Resolution/3D Std + Bone.5 to.75mm.5mm 3mm 2mm 2mm

4 294 Appendix: Sample CT Protocols Parameters Paranasal Sinuses Helical NO mm.5 to.75mm 1 Optional cc 25 to 50cc 2cc/sec No Yes 70 sec Std + Bone.5 to.75mm.5mm 2mm 2mm Top of Orbits Through Parameters Mandible Helical NO mm.5 to.75mm 1 Optional cc 25 to 50cc 2cc/sec No Yes 70 sec Std + Bone.5 to.75mm.5mm 2mm 2mm 2mm Orbits/Facial Bones Sinus

5 Appendix: Sample CT Protocols 295 Parameters Lung Apex to Soft Palate Helical Yes 0.5 sec 240mm.5 to.75mm 1.25 Optional cc 25 to 50cc 2cc/sec No Yes 45 sec Standard.5 to.75mm.5mm 3mm 2mm 2mm Parameters Tip of Mastoid to Sella Helical no 1 sec 240mm.5 to.75mm 1 Optional cc 25 to 50cc 2cc/sec No Yes 70 sec Std + Bone.5 to.75mm.4 to.5mm 1mm 1mm IAC Neck

6 296 Appendix: Sample CT Protocols Parameters Spine Area of Interest Helical Yes 1 sec 240mm.5 to.75mm 1 No Std + Bone.5 to.75mm.5mm 2mm 2mm 2mm Total Spine or Area of Parameters Interest Helical Yes 1 sec 240mm 1 to 1.5mm 1 No Std + Bone 1 to 1.5mm 1mm 2mm 2mm 2mm Total Spine Spine (C, T or L alone)

7 Appendix: Sample CT Protocols 297 Lung Apex Through Adrenal Parameters Glands Helical Yes 0.5 sec 500mm.5 to.75mm 1.25 Optional cc 25 to 50cc 2cc/sec Optional Desc. aorta sec 10 sec Yes (O) 50 to 60 sec Std + Lung.5 to.75mm.5mm 3mm Optional 3mm Lung Apex Through Adrenal Parameters Glands Helical Yes 0.5 sec 500mm.5 to.75mm 1.25 No Reconstruction #1 Reconstruction #2 Algorithm Thin Axials Recon Interval Thick Axials Sagittal Coronal Std + Lung.5 to.75mm.5mm 3mm Optional 3mm Algorithm Thin Axials Recon Interval Thick Axials Sagittal Coronal Lung 1mm 1 to 10mm Chest Chest High Resolution Procedure note: Additional scans in the prone position can be obtained if needed. I also recommend obtaining a select series of expiratory scans. High resolution images can be reconstructed contiguously or at select intervals depending on radiologist preference.

8 298 Appendix: Sample CT Protocols Lung Apex Through Pubic Parameters Symphysis Helical Yes 0.5 sec 500mm 1 to 1.5mm 1.25 Yes cc 50 cc 2cc/sec Contrast Timing Bolus Detection Reference Location Trigger Value (ROI) Optional Desc. aorta sec Yes (O) 50 to 60 sec Chest - Abdomen - Pelvis Std + Lung 1 to 1.5mm 1mm 3-5mm Optional 3mm Diaphragm Through Iliac Parameters Crest or Pubic Symphysis Helical Yes 0.5 sec 500mm 1 to 1.5mm 1.25 Yes 100cc 50cc 2cc/sec Optional Desc. aorta Yes (O) 70 sec Standard 1 to 1.5mm 1mm 3-5mm Optional 2mm Abdomen or Abd/Pelvis

9 Appendix: Sample CT Protocols 299 Acquistion #1 Liver - Late Arterial Phase Helical Yes 0.5 sec 500mm 1 to 1.5mm 1.25 Acquistion #2 Abd - Portal Venous Phase Helical Yes 0.5 sec 500mm 1 to 1.5mm 1.25 Acquistion Liver - Delay Equilibrium #3 Phase (Optional) Helical Yes 0.5 sec 500mm 1 to 1.5mm 1.25 Yes 125cc 50cc 4cc/sec Contrast Timing Bolus Detection Reference Location Trigger Value (ROI) Trigger Manual Delay #1 Delay #2 Delay #3 Optional Abd aorta sec 5 sec Yes (O) 28 sec 60 sec 120 sec #1 Standard 1 to 1.5mm 1mm 3mm Optional 3mm s #2, #3 Standard 1 to 1.5mm 1mm 3mm Optional 3mm Multiphase Phase Liver

10 300 Appendix: Sample CT Protocols Acquistion #1 Pancreas - Pre contrast Helical Yes 0.5 sec 500mm 1 to 1.5mm 1.25 Acquistion Pancreas - Pancreatic #2 Phase Helical Yes 0.5 sec 500mm.5 to.75mm 1.25 Acquistion #3 Abdomen - Venous Phase Helical Yes 0.5 sec 500mm 1 to 1.5mm 1.25 Yes 125cc 50cc 3cc/sec Trigger Manual Delay #2 Delay #3 Optional Abd aorta sec 10 sec Yes (O) 40 sec 70 sec #1 Standard No 5mm #2 Standard.5 to.75mm.5mm 2mm Optional 2mm #3 Standard 1 to 1.5mm 1mm 3mm Optional 3mm Pancreas Protocol

11 Appendix: Sample CT Protocols 301 Acquistion #1 Non Contrast Helical Yes 0.5 sec 500mm.5 to.75mm 1.25 Acquistion Post Contrast - Venous #2 Phase (Optional) Helical Yes 0.5 sec 500mm.5 to.75mm 1.25 Yes 100cc 25 to 50cc 2cc/sec Contrast Timing Bolus Detection Reference Location Trigger Value (ROI) Manual Delay #2 Trigger No Yes 70 sec #1 Standard.5 to.75mm.5mm 3mm 3mm #2 Standard.5 to.75mm.5mm 3-5mm Optional 3mm Mode kv ma AEC Rotation Time AEC SliceThickness Beam Pitch Diaphragm Through Pubic Parameters Symphysis Helical Yes 0.5 sec 500mm 1 to 1.5mm 1.25 No Trigger Manual Delay Standard 1 to 1.5mm 1mm 3mm Optional 3mm Abdomen/Pelvis Stone Survey Adrenal Gland

12 302 Appendix: Sample CT Protocols Acquistion #1 Kidney Pre Contrast Helical Yes 0.5 sec 500mm 1 to 1.5mm 1.25 Acquistion #2 Abdomen - Venous Phase Helical Yes 0.5 sec 500mm 1 to 1.5mm 1.25 Acquistion #3 Kidney Excretory Phase Helical yes 0.5 sec 500mm 1 to 1.5mm 1.25 Yes 125cc 50cc 2cc/sec Trigger Manual Delay #2 Delay #3 No Yes 70 sec 3-5 minutes #1 Standard 1 to 1.5mm 1mm 3mm Optional Optional #2 Standard 1 to 1.5mm 1mm 3mm Optional 3mm #3 Standard 1 to 1.5mm 1mm 3mm Optional 3mm Renal Mass Protocol

13 Appendix: Sample CT Protocols 303 Acquistion #1 Abd/pel Pre Contrast Helical Yes 0.5 sec 500mm 1 to 1.5mm 1.25 Acquistion Abdomen Mixed #2 Nephrographic/Excretory Helical Yes 0.5 sec 500mm 1 to 1.5mm 1.25 Acquistion Lower Abdomen and Pelvis #3 Excretory Phase Helical Yes 0.5 sec 500mm 1 to 1.5mm 1.25 Injection 1 Yes 50cc 50cc 2cc/sec Contrast Needed Contrast Volume Saline Volume Injection Rate Injection 2 Yes 75cc 50cc 1.5cc/sec Manual Delay #2 Delay #3 Trigger No Yes See Note See Note #1 Standard 1 to 1.5mm 1mm 3mm Optional 3mm #2 Standard 1 to 1.5mm 1mm 3mm Optional 3mm #3 Standard 1 to 1.5mm 1mm 3mm Optional 3mm Procedure note: This protocol uses a split contrast injection. Inject 50 cc of contrast and apply abdominal compression. Wait 5 minutes then inject remaining 75 cc of contrast. through kidneys at 60 seconds post start of second injection to obtain mixed nephrographic/excretory images. Wait an additional 3-5 minutes, release compression and immediately scan lower abdomen and pelvis. CT Urogram (hematuria protocol)

14 304 Appendix: Sample CT Protocols Acquistion Supine with Gas #1 Insufflation Helical Yes 0.5 sec 500mm 1 to 1.5mm 1.25 Acquistion Mode kv ma AEC Time FOV SliceThickness Beam Pitch Prone with Gas #2 Insufflation Helical Yes 0.5 sec 500mm 1 to 1.5mm 1.25 No Trigger Manual Delay #1 Delay #2 #1 Standard 1 to 1.5mm 1mm 3mm #2 Standard 1 to 1.5mm 1mm 3mm Procedure note: Air or carbon dioxide gas insufflation needed to distend colon. Patient scanned supine and prone with low dose technique. Send thin section reconstructions to workstation for evaluation. CT Colography Protocol

15 Appendix: Sample CT Protocols 305 Knee, Ankle, Foot, Elbow, Parameters Wrist or Hand Helical No 0.5 sec 240mm.5 to.75mm 1 No Std + bone.5 to.75mm.4 to.5mm 2 to 3mm 2mm 2mm Procedure note: Reconstruction with bone algorithm improves thick reconstructions for PACS, but 3D images are usually better with standard reconstruction algorithm. Oblique reconstructions made on the scanner or workstation are usually preferable to straight coronal and sagittal reconstructions, but must be individually tailored to anatomy. Shoulder, Scapula, Hip, Parameters Pelvis, Entire Arm or Leg Helical No 0.5 sec 500mm 1 to 1.5mm 1 No Std + bone 1 to 1.5mm.8 to 1mm 2mm 2mm 2mm Procedure note: Reconstruction with bone algorithm improves thick reconstructions for PACS, but 3D images are usually better with standard reconstruction algorithm. Oblique reconstructions made on the scanner or workstation are usually preferable to straight coronal and sagittal reconstructions, but must be individually tailored to anatomy. Central Joint Peripheral Joint

16 306 Appendix: Sample CT Protocols CTA Protocols Parameters Skull Base to Vertex Helical no 0.5 sec 240mm.5 to.75mm 1 Yes cc 50cc 4cc/sec Reference Location Trigger Value (ROI) Delay After Contrast Timing Bolus Detection Yes Skull Base Visual Blush 10 secs 0 Yes (O) sec Head Angio (COW) Standard.5 to.75mm.4 to.5mm 2-3mm Optional Optional Parameters Aortic Arch to Skull Base Helical Yes.4 to.5 sec 240mm.5 to.75mm 1.25 Yes cc 50cc 4cc/sec Reference Location Trigger Value (ROI) Delay After Contrast Timing Bolus Detection Yes Aortic Arch Optional 20 sec Arch and Carotids Standard.5 to.75mm.4 to.5mm 3mm Optional Optional

17 Appendix: Sample CT Protocols 307 Diaphragm to Apex Inferior to Superior Parameters Helical Yes.4 to.5 sec 500mm.5 to.75mm 1.25 Yes 100 to 125cc 50cc 4cc/sec Reference Location Trigger Value (ROI) Delay After Contrast Timing Bolus Detection Yes Pulm Artery Optional sec Std + Lung 1 to 1.5mm 1mm 2mm Optional 2mm Parameters Apex to Below Diaphragm Helical Yes.4 to.5 sec 500mm.5 to.75mm 1.25 Yes 100cc 50cc 4-5cc/sec Reference Location Trigger Value (ROI) Delay After Contrast Timing Bolus Detection Yes Arch Optional sec Std + Lung.5 to.75mm.4 to.5mm 3mm 2mm (oblique) 2mm Chest Thoracic Aorta Chest Pulmonary Embolus

18 308 Appendix: Sample CT Protocols Parameters Apex to Below Bifurcation Helical Yes.4 to.5 sec 500mm 1 to 1.5mm 1.25 to 1.5 Yes 100 to 125cc 50cc 4-5cc/sec Reference Location Trigger Value (ROI) Delay After Contrast Timing Bolus Detection Yes Arch Yes (O) sec Standard 1 to 1.5mm 1mm 3mm 2mm (oblique) 3mm Diaphragm to Below Bifurcation or to Groin Parameters Helical Yes.5 sec 500mm.5 to.75mm 1.25 Yes 100cc 50cc 4-5cc/sec Reference Location Trigger Value (ROI) Delay After Contrast Timing Bolus Detection Yes Abd Aorta Yes (O) sec Standard.5 to.75mm.4 to.5mm 3mm Optional Optional Procedure note: Aneurysm and mesenteric studies should extend all the way to the femoral bifurcation. Renal studies can end below the aortic bifurcation. Abdominal Angio Total Aorta (Dissection Protocol)

19 Appendix: Sample CT Protocols 309 Parameters Injector Values Heart Helical no.4 to.5 sec 320mm.5 to.75mm Contrast Timing Contrast Needed Contrast Volume Saline Volume Injection Rate Yes 125 to 150cc 50cc 4cc/sec Reconstructions Reference Location Trigger Value (ROI) Delay After Bolus Detection Yes Ascen Aorta secs 0 Yes (O) 20 sec Algorithm Thin Axials Recon Interval Thick Axials Sagittal Coronal Standard.5 to.75mm.4 to.5mm 2mm Optional Optional Procedure note: This exam must be performed with retrospective gating. Pitch will vary depending on heart rate with a typical range of.2 to.4. Reconstructions should be made at multiple phases of the R-R inverval. Parameters Arch to Hand Helical Yes.5 sec 500mm 1mm 1.25 Yes 125cc 50cc 3cc/sec Reference Location Trigger Value (ROI) Delay After trigger Manual Delay Contrast Timing Bolus Detection Yes Aortic Arch s 0 Yes (O) sec Standard 1mm 1mm 3mm Optional Optional Procedure note: Position arm (or both arms if Needed) over the patients head. Be sure IV is not in arm of interest. A leg or femoral IV works best for evaluation of both arms and subclavian arteries. Arm Angio Cardiac CTA

20 310 Appendix: Sample CT Protocols 1 Parameters Diaphragm to Feet Mode kv ma Real EC Rotation Time FOV SliceThickness Beam Pitch Helical no.5 sec 500mm 1 to 1.5mm if Needed Above Knee to Feet Mode kv ma Real EC Rotation Time FOV SliceThickness Beam Pitch Helical No.5 sec 500mm 1mm 1.25 Yes 125 to 150cc 50cc 3cc/sec Contrast Timing Sure Start Yes Reference Location Trigger Value (ROI) Delay After Femoral Artery Visual Blush 30 secs 0 Yes (O) 40s ecs Standard 1 to 1.5mm 1mm 3-5mm Optional Optional Procedure note: Preprogrammed second run from above knee to feet. Use realtime image reconstruction. If no contrast below knees run the second pass. If contrast present, abort second run. Aorta with Runoff

21 Index A Abdomen, scan parameters, 298 Abdominal aorta, Aberrant right coronary artery, teaching case, Accessory renal artery stenosis, 56 Adrenal gland, scan parameters, 301 Aneurysmal bone cyst of mandible, teaching case, Aneurysms abdominal aorta imaging, anterior communicating artery aneurysm, 68 cerebral, teaching case, ruptured mycotic aortic aneurysm, 71 Angiograph. See CT angiography Ankle, hemophilic arthropathy, Anterior communicating artery aneurysm, 68 Aortic aneurysm, ruptures, 71 Aortic arch imaging, 69 Aortic coarctation, teaching case, Aortic dissection, teaching case, Aortic occlusion with axillary/ femoral bypasses, teaching case, Aortic occlusion with collateral pathways, teaching case, Aortic stent-graft with endoleak, teaching case, Aortic transection, traumatic, teaching case, Aortogram, scan timing, 25 Arachnoiditis, teaching case, Archiving data, 61 Arrhythmias, cardiac imaging technique, 19 Artifacts, blurring, dropout area artifacts, 58 general conditions related to, motion artifacts, 56 pulsation artifacts, reconstruction, streak artifacts, windmill artifacts, 32 Atrial myxoma, teaching case, Automated segmentation, pros/cons of, seed detection, 53 thresholding, 53 uses of, 53 Automatic exposure control (AEC), Averaging effects maximum intensity projection, overcoming, 47 B Beam pitch, 9 Bile duct, common stones, 48 Biphasic injections, 27 Blurring, conditions related to, Body imaging, 77 80, cavernous hemangioma, colonography, crossed-fused renal ectopia with ureteropelvic junction obstruction, cystic bronchiectasis, gastric cancer, indications for, lung cancer, methods, pancreatic cancer, pancreatitis with splenic vein thrombosis, polysplenia, pulmonary sequestration, renal cell carcinoma, small bowel obstruction, surface imaging, 80 tracheal bronchus, tracheal carcinoma, ureteral stricture, Bolus triggering method, Bowel obstruction, small bowel, teaching case, Brain imaging helical mode, 7 See also Neuroimaging Breast, leptomeningeal carcinomatosis, 37 Brodie abscess, teaching case, Bypass graft evaluation, teaching case, C C1 fracture, teaching case, Calcification, carotid bifurcation, 69 Calcium scoring, prospective gating,

22 312 Index Calcium screening, coronary, teaching case, Cancer. See Body imaging Cardiac imaging, 14 19, aberrant right coronary artery, arrhythmias, effects of, 19 atrial myxoma, bypass graft evaluation, coronary artery CTA, coronary calcium screening, coronary stent evaluation, ECG modulation, helical pitch, 17 prospective gating, pulmonary vein evaluation, radiation reduction, 17 retrospective imaging, See also CT angiography (CTA) Carotid artery bifurcation, 69 carotid thrombus, teaching case, CT angiography (CTA), 69 stenosis. See Carotid stenosis Carotid stenosis bilateral, 70 segmental image, 55 teaching cases, Cavernous hemangioma, teaching case, Central joint, scan parameters, 305 Cerebral aneurysms, teaching case, Cherumbism of the mandible, teaching case, Chest chest-abdomen-pelvis, scan parameters, 298 CT angiography (CTA), gunshot wound, right ventricular, rapid multiple trauma evaluation, scan parameters, Circle of Willis (COW) CT angiography (CTA), VR image, 68 Circumflex artery stenosis, Cocaine vasculitis, teaching case, Colon colography, scan parameters, 304 colonography, teaching case, colon polys endoluminal image, 51, Communication, with referring doctor, 61 Computerized tomograhy angiography (CTA). See CT angiography (CTA) Congenital scoliosis, teaching case, Contrast media (CM), amount and density, biphasic injections, 27 bolus triggering method, contrast enhancement curve, 23 distribution after injection, 22 dual head injectors, 27 injection duration, effects of, 22 injection duration formulas, 26 protocol design, saline flush, standard injection rates, 27 test bolus method, 24 Coronary artery aberrant right coronary artery, bypass graft evaluation, calcium screening, CTA coronary blood vessels imaging, 50 stent evaluation, teaching cases, Craniosynostosis, teaching case, Crossed-fused renal ectopia with ureteropelvic junction obstruction, teaching case, CT angiography (CTA), abdominal arota imaging, aortic arch imaging, 69 below knee arteries, 75 benefits of, 4, 64 carotid artery imaging, 69 chest CTA, Circle of Willis (COW) examinations, data set review, data set segmentation, multiple rendering, importance of, 67 Curved planar reconstruction, pros/cons of, 42 software automation methods, 47, 49 technique for, 47 uses of, 42, 47 Cystic bronchiectasis, teaching case, D Detector pitch, 9 Digital subtration angiography (DSA), 64 Dose parameters. See Radiation dose Double oblique reconstructions, orthopedic imaging, Dropout area artifacts, 58 Dual head injectors, 27 E Ear, internal auditory canal (IAC) scan parameters, 295 ECG modulation, Edge distortions, conditions related to, 31 Embolism, pulmonary, Endoluminal imaging pros/cons of, 42 software features, 51 uses of, 42, 51 Epiglottitis, acute, 36 Errors image noise, rendering errors, 54 segmentation errors, See also Artifacts; specific type of error Extremity fractures teaching cases, See also Orthopedic imaging F Facial bones fractures, multiple, teaching case, scan parameters, 306 Fields of view (FOV) size and isotropic voxel, 5 6 and slice thickness, 7 8 Filters, reconstruction, Fractures. See Orthopedic imaging G Gastric cancer, teaching case, Gating, cardiac imaging, Gunshot wound, right ventricular, H Hand, osteochondroma of, teaching case, Hardware. See Prostheses/ hardware Head multiple facial fractures, scan parameters, 293

23 Index 313 Helical pitch beam pitch, 9 cardiac imaging, 17 changing, effects on scan, 9 detector pitch, 9 Helical scanning, 7 Hemophilic arthropathy, teaching case, High-resolution scanning problems related to, 8 9 protocol design, 7 9 I Iliac artery iliac occlusion, streak artifact, 59 iliac stents, 48 Image noise, causes, resolving, 61 Image reconstruction, artifacts, edge distortions, 31 multiplanar reconstructions, multislice, benefits of, overlapping reconstruction, PACS system-created MPRs, 38 in real time, 33 reconstruction algorithm, 31 reconstruction filters, reconstruction times, 31 scanner-created MPRs, slice thickness, Image rendering. See 3D workstations Image review, cross-referencing in, 39 electronic, benefits of, 39 PACS system, 35, 39 soft copy image review, workflow aspects, Injection of contrast medium. See Contrast media (CM) Internal auditory canal (IAC), scan parameters, 295 Iodine flux, control of, 22 Isotropic voxels, and fields of view (FOV), 5 6 K Kidney accessory renal artery stenosis, 56 crossed-fused renal ectopia with ureteropelvic junction obstruction, renal artery stenosis, renal cell carcinoma, renal mass scan parameters, 302 Knees arthrogram, teaching case, below knee imaging, 75, 93 brodie abscess, L Langerhans cell histiocytosis, teaching case, Leptomeningeal carcinomatosis, 37 Liver amount of contrast medium, 27 metastasis, 37 scan parameters, 299 scan timing, 25 Lungs cancer, cystic bronchiectasis, pulmonary sequestration, tracheal bronchus, tracheal carcinoma, M Mandible aneurysmal bone cyst, teaching case, cherubism of, Manual segmentation manual sculpting, 52 uses of, 52 Maximum intensity projection, averaging effects, pros/cons of, 42, 47 technique for, 45 uses of, 42, 46 variable sliding slab method, 47 Meningioma with sinus thrombosis, teaching case, Mesenteric artery mesenteric fibrosis, 79 mesenteric ischemia, teaching case, Metal hardware. See Prostheses/ hardware Middle cerebral artery (MCA) stroke, teaching case, Motion artifacts causes of, 56 resolving, 56 Multidetector CT (MDCT) body imaging, cardiac imaging, 14 19, contrast media (CM), equipment needs, 3 fields of view (FOV), 5 6 helical pitch, 9 helical scanning, 7 image reconstruction, image review, neuroimaging, orthopedic imaging, parameters. See parameters patients with metal hardware/ prostheses, 14 pediatric imaging, protocols, components of, radiation dose parameters, rotation time, sequence scanning, 7 slice thickness, 7 9 3D workstations, trauma imaging, vascular imaging, workflow, Multiplanar reconstructions, pros/cons of, 42 technique for, 43 uses of, 42, 43 Mycotic aortic aneurysm, ruptured, 71 N Neck, scan parameters, 295 Neuroimaging, arachnoiditis, carotid thrombus, cerebral aneurysms, cocaine vasculitis, meningioma with sinus thrombosis, occipital arteriovenous malformation, right MCA stroke, sphenoidal encephalocele, spinal arachnoid cyst, Noise. See Image noise O Obesity CT venogram, 60 excessive noise problem, Oblique reconstructions, orthopedic imaging, Occipital arteriovenous malformation, teaching case, Orbits orbital fractures, scan parameters, 294 Orthopedic imaging, 75 77, aneurysmal bone cyst of mandible, brodie abscess, cherubism of mandible, congenital scoliosis,

24 314 Index Orthopedic imaging (cont.) double oblique reconstructions, extremity fractures, helical pitch, 9 hemophilic arthropathy, knee arthrogram, nonunion scaphoid, 44 oblique reconstructions, odontoid, postoperative image, 43 osteochondroma of hand, posterior labral tear of shoulder, radial fracture nonunion, radial head fracture, rendering errors, 54 scaphoid fracture nonunion, segmentation methods, 77 skull/orbital fractures, surface rendering, 77 volume rendering, 77 Osteochondroma of hand, Overlapping reconstruction, P PACS systems image review process, 35, 39 PACS-created MPRs, 38 sharpening filter, Pancreas pancreatic cancer, pancreatitis with splenic vein thrombosis, scan parameters, 300 scan timing, 25 Pediatric imaging, aneurysmal bone cyst of mandible, aortic coarctation, cavernous hemangioma, cervical spine pseudofracture, 57 cherumbism of the mandible, congenital scoliosis, craniosynostosis, cystic bronchiectasis, langerhans cell histiocytosis, osteochondroma of hand, pulmonary sequestration, skull/orbital fractures, tracheal bronchus, vascular ring, Pelvis stone survey, scan parameters, 301 Peripheral joint, scan parameters, 305 Peripheral vascular disease below the knee imaging, 75, 93 imaging needs, teaching cases, Perspective volume rendering. See Endoluminal imaging Polysplenia, teaching case, Posterior labral tear of shoulder, Prospective gating, cardiac imaging, Prostheses/hardware odontoid fracture image, 43 scan technique, 14 spinal fusion, 79 Protocols, workflow efficiency, Pseudoaneurysm, ulnar artery pseudoaneurysm, Pseudostenosis of right SFA, 57 Pulmonary embolism, teaching case, Pulmonary sequestration, teaching case, Pulmonary vein evaluation, teaching case, Pulmonary vessels, MIP image, 46 Pulsation artifacts, causes of, 57 recognizing, 58 resolving, 58 R Radial fracture nonunion, Radial head fracture, Radiation dose, automatic exposure control (AEC), dose-buildup effect, 11 ECG modulation, radiation penumbra, and slice thickness, 10 x-y tube current modulation, 12 z-axis modulation, 12 Radiation reduction cardiac imaging, 17 methods for, 10 Rapid multiple trauma evaluation, teaching case, Real time, image reconstruction in, 33 Reconstruction. See Image reconstruction Renal artery stenosis accessory, 56 teaching case, Renal cell carcinoma, teaching case, Renal mass, scan parameters, 302 Rendering errors, causes, 54 Retrospective imaging, cardiac imaging, Rotation time, changing, effects of, g-force against, 13 routine time, 13 Runoff, lower legs, S Saline flush, mode, helical pitch, 7, 9 ner-created MPRs, parameters abdomen, 299 adrenal gland, 301 central joint, 305 chest, 307 chest-abdomen-pelvis, 298 colography, 304 facial bones, 294 head, 293 internal auditory canal (IAC), 294 liver, 299 neck, 295 orbits, 293 pancreas, 300 pelvis stone survey, 301 peripheral joint, 305 renal mass, 302 sinus, 294 spine, 296 urogram, 303 timing, for aortogram, 25 bolus triggering method, for parenchymal organs, 25 test bolus method, 24 Scaphoid fracture nonunion image sculpting, 44 teaching case, Scoliosis, congenital, teaching case, Sculpting, manual, 52 Seed detection, 53 Segmentation errors, causes of, resolving, 55 Segmentation methods, automated segmentation, errors related to, manual segmentation, 52 orthopedic imaging, 77 Sequence scanning, uses of, 7 Shoulder, posterior labral tear, Sinus, scan parameters, 294

25 Index 315 Skull craniosynostosis, langerhans cell histiocytosis, skull/orbital fractures, teaching case, Slice thickness, 7 9 and fields of view (FOV), 7 8 and image reconstruction, MDCT options, 7 protocol design, 7 9 and radiation dose, 10 submillimeter slice thickness, 7 8 Small bowel obstruction, teaching case, Soft copy image review, Sphenoidal encephalocele, teaching case, Spine C1 fracture, teaching case, cervical spine pseudofracture, 57 congenital scoliosis, nodular enhancement, 37 scan parameters, 296 spinal arachnoid cyst, spinal fusion, 78 vertebral body fracture, Streak artifacts, causes of, 58 identifying, image reconstruction, 32 Stroke, right MCA, teaching case, Submillimeter slice thickness, uses of, 7 8 Superficial femoral artery (SFA) occlusions, 46, 57 teaching cases, Superficial femoral artery (SFA) pseudostenosis, 57 Surface imaging, body imaging, 80 Surface rendering, orthopedic imaging, 77 pros/cons of, 42, 45 technique for, uses of, 42, 45 T Teaching units. See Body imaging; Cardiac imaging; Neuroimaging; Orthopedic imaging; Vascular imaging Test bolus method, 24 3D workstations, 3, archiving data, 61 automated segmentation, best uses of methods, 42 curved planar reconstruction, endoluminal imaging, 51 manual segmentation, 52 maximum intensity projection, multiplanar reconstructions, 43 problems of. See 3D workstations issues pros/cons of methods, 42 surface rendering, volume rendering, D workstations issues artifacts, excessive image noise, rendering errors, 54 segmentation errors, Thresholding, automated segmentation, 53 Timing of scan. See timing Tracheal bronchus, teaching case, Tracheal carcinoma, teaching case, Trauma imaging, C1 fracture, extremity fractures, gunshot wound, right ventricular, teaching case, multiple facial fractures, rapid multiple trauma evaluation, skull/orbital fractures, traumatic aortic transection, vertebral body fracture, Traumatic aortic transection, teaching case, U Ulnar artery pseudoaneurysm, teaching case, Ureteral stricture, teaching case, Urogram normal, 80 scan parameters, 303 V Variable sliding slab method, 47 Vascular imaging, anterior communicating artery aneurysm, 68 aortic coarctation, aortic dissection, aortic occlusion with axillary/ femoral bypasses, aortic occlusion with collateral pathways, aortic stent-graft with endoleak, carotid stenosis, 55, 70, circumflex artery stenosis, coronary artery CTA, 72 coronary blood vessels, 50 iliac stents, 48 mesenteric fibrosis, 79 mesenteric ischemia, peripheral vascular disease, 72 75, pseudostenosis of right SFA, 57 pulmonary embolism, pulmonary vessels MIP image, 46 pulsation artifacts, 56, 58 renal artery stenosis, rendering errors, 54 ruptured mycotic aortic aneurysm, 71 superficial femoral artery (SFA) occlusions, 46, 57 ulnar artery pseudoaneurysm, vascular ring, Vascular ring, teaching case, Vertebral body fracture, teaching case, Volume rendering, image appearance, varying, 49 interactivity of, 50 orthopedic imaging, 77 pros/cons of, 42, technique for, 49 uses of, 42 Volumetric imaging benefits of, 4 equipment needs, 3 W Windmill artifacts, 32 Workflow, comprehensive protocol (chart), 84 CT protocols, creation of, flowchart, 86 image review, Workstations. See 3D workstations Wrist scaphoid fracture nonunion, 44, ulnar artery pseudoaneurysm, X X-y tube current modulation, 12 Z Z-axis modulation, 12