2017 myresearch Science Internship Program: Applied Medicine. Civic Education Office of Government and Community Relations

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1 2017 myresearch Science Internship Program: Applied Medicine Civic Education Office of Government and Community Relations

2 Nevaeh Miller Science Internship Program: Applied Medicine

3 A Combined Spiral CT Scan of Sinus and the Brain May Alter the Amount of Radiation Delivered to the Patient Nevaeh Miller Frank Dong, PHD Ellen Park, MD

4 Abstract When performing CT Scans in pediatric patients for simple sinus and the brain, two different techniques are performed. An axial scan is utilized for a CT of the brain and a spiral scan is performed for a CT of the simple sinus. There is an overlap of scan around the orbits when performing both scans at the same time, however, radiation to the orbits should be minimized as the orbits are radiosensitive. Performing a CT scan utilizing a single spiral technique may change the overall radiation dose when compared to performing both a CT sequential scan through the brain and a CT spiral scan through the limited sinuses.

5 Background Traditionally, a CT of the brain is performed in sequential technique and a CT of the simple sinus is performed in spiral technique, covering only a limited amount of the sinus. In the outpatient setting, both CT of the brain and CT of the simple sinus may be ordered for the evaluation of headaches.

6 Background Computed Tomography Dose Index (CTDI) is a standardized dose metric for CT. CTDIvol represents the average dose across the field-of-view (FOV) in the mid-plane of the scanned volume for helical scans. DLP refers to Dose Length Product DLP = exposure length x CTDI vol DLP approximates the integrated dose along the scan range; therefore, clinically DLP is often used to indicate total energy deposited.

7 Problem/Purpose There is an overlap of radiation to the orbits when a pediatric patient receives separate CT scans of the brain and simple sinus at the same time. The purpose of the study was to evaluate radiation dose to the patient and orbits when performing CT scans of the brain and simple sinus with two different techniques using sequential and spiral versus one spiral technique, and compare the overall radiation doses.

8 Hypothesis Performing a CT of the brain and simple sinus utilizing the single spiral technique rather than sequential and spiral techniques may reduce radiation doses to the orbits and patient.

9 Methodology Experimented with a 16 cm diameter head phantom Performed a combined CT scan of the brain followed by another CT scan for sinus in single spiral technique Performed a separate CT scan of the brain in sequential technique Performed a separate CT scan for simple sinus in spiral technique Recorded the Computed Tomography Dose Index (CTDI) & recorded the Dose Length Product (DLP)

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11 Data (cont.) All patients under 18 years old who had CT of the simple sinuses were first identified and there were 329 total. Of these patients, the patients who had both CT of brain and simple sinus on the same day were isolated which were 30 in total. The CTDI and DLP were recorded and added for both the CT of the brain and simple sinus.

12 Data (cont.) Name CTDI_Sinus DLP_Sinus CTDI_Brain DLP_Brain Patient Patient Patient Patient Patient Patient Patient Patient Patient Patient Patient Patient Patient Patient Patient Patient Patient Patient Patient Patient

13 Results A total of 5 patients between the ages of 0-5 years old were identified who received both CT of the brain and simple sinuses. The average CTDI of total brain + sinus in 0-5 year old patients was with mean of This average and mean CTDI vol is similar to that of the phantom imaging of 32.7 in the typical scenario.

14 Conclusions No significant difference in the amount of CTDI vol and Patient Orbit Dose was observed between the group of single spiral technique imaging of CT brain and simple sinus versus two different techniques of CT brain and CT simple sinus. This may be secondary to comparing CT of simple sinuses rather than CT of stereo sinus, which images the sinuses entirety as would be performed under single spiral CT of the brain and sinus

15 Recommendations Further study is needed to compare the radiation doses in studies where patients have received a stereo sinus procedure which is a procedure that makes it more easier for a physician to get a view of the sinus.

16 References Beale T, Brown J, Route J. ENT, neck and dental radiology. In: Adam A, Dixon AK, Gillard JH, Schaefer- Prokop CM, eds. Grainger & Allison's Diagnostic Radiology: A Textbook of Medical Imaging. 6th ed. New York, NY: Churchill Livingstone; 2014:chap 67. Shaw, A.S., Dixon, A.K. Multidetector computed tomography. In: Adam A, Dixon AK, eds. Grainger & Allison's Diagnostic Radiology: A Textbook of Medical Imaging. 5th ed. New York, NY: Churchill Livingstone; 2008:chap 4. Thomsen, H.S., Reimer, P. Intravascular contrast media for radiology, CT, and MRI. In: Adam A, Dixon AK, Gillard JH, Schaefer-Prokop CM, eds. Grainger & Allison's Diagnostic Radiology: A Textbook of Medical Imaging. 6th ed. New York, NY: Churchill Livingstone; 2014:chap 2. Walden, M.J., Zinreich, S.J., Aygun N. In: Flint PW, Haughey BH, Lund LJ, et al, eds. Cummings Otolaryngology: Head & Neck Surgery. 6th ed. Philadelphia, PA: Elsevier Mosby; 2015:chap 41. Menoch, M. J., Herish, D. A., Khan, N. S., Simon, H. K., & Sterm, J. J. (2012, March). Trends in Computed Tomography Utilization in the Pediatric Emergency Department. Retrieved July 17, 2017, from

17 Special Thanks Ellen Park, MD Frank Dong, PHD Darlene Bublavy Nedra Starling, MA, MPH, DrPH/ABD Cleveland Clinic Office of Government and Community Relations Department of Civic Education

18 Copyright 2017 Cleveland Clinic Foundation