Clinical Trial Details
— Status: Completed
Administrative data
NCT number |
NCT03159377 |
Other study ID # |
SHEBA - 16- 3651- EM - CTIL |
Secondary ID |
|
Status |
Completed |
Phase |
|
First received |
|
Last updated |
|
Start date |
July 4, 2017 |
Est. completion date |
July 6, 2021 |
Study information
Verified date |
October 2021 |
Source |
Sheba Medical Center |
Contact |
n/a |
Is FDA regulated |
No |
Health authority |
|
Study type |
Observational
|
Clinical Trial Summary
We will perform an ultra low-dose CT (ULDCT) in addition to a regular chest CT scan for adult
patients undergoing a clinically indicated chest CT. Using a recently developed
computationally efficient algorithm for the denoising of ULDCT scans after image
reconstruction, we will compare the sensitivity, specificity and accuracy of lesion detection
with the ULDCT as compared to the regular CT scan.
Description:
Patient cohort: Two hundred patients will be recruited for this study. Patients will be
comprised of two groups: an inpatient group of patients from the Internal Medicine Department
E for which a chest CT is ordered during their hospitalization; and ambulatory patients
arriving for an ambulatory chest CT in the early afternoon. The treating clinician ordering
the chest CT for the patients from Internal Medicine E will consent the inpatients while a
chest radiologist from the Radiology Department will consent the outpatients arriving in the
early afternoon for a chest CT study. For inclusion in the study, patients will be adults,
older than 18 years old with the ability to follow orders and hold their breath for 8 seconds
as determined by the physician at time of study consent.
Imaging method: All patients consented for this study will be imaged on a dedicated scanner
for the study, Revolution (GE, Milwaukee, WI). Immediately following the patient's diagnostic
chest CT scan, an ultra low dose chest CT scan will be obtained. The routine CT scans of the
patients consented for this study will be performed using our routine protocol on the GE
Revolution which typically delivers at our institution an average effective dose of 2.9mSv
(range 0.95-3.01mSv) while our other Philips routine chest CT scan delivers an average
effective dose of 10.5mSv (range 10.29-12.95mSv). With the addition of the ultra low dose
technique, which delivers a radiation dose of a range of 0.5-1 mSv (calculated from a pilot
study we obtained on pigs), patients are expected to get an total radiation dose for both
scans together of about 4 mSv which is less than 10.5mSv (the normal dose for the Phillips CT
machine at our institution). Just as a comparison, a meticulous study looking at multiple
institutions showed that the average effective dose from a routine chest CT is 7mSv, range
4-18mSv and for a chest CT with pulmonary embolism protocol an average effective dose of
15mSv with a range of 13-40mSv .
Image evaluation: The diagnostic chest CT scan will be sent to the PACS as usual and
interpreted immediately, during the same day, as per normal inpatient clinical operations
protocol at our institution. The ultra low dose CT scan will be automatically sent to the
computational imaging lab processing station, which will denoise the image. After denoising
the images will be automatically forwarded to the PACS under the same accession number of the
routine chest CT scan. Comparison of the ultra low dose denoised images to the routine chest
CT images will be performed by an experienced chest radiologist at a later date, at least one
week after date of acquisition to prevent any memorability of the original image.
Radiologists' memory of findings has been shown to be poor, even when viewed immediately but
slightly worse when time passes [Evans]. The radiologist will document the presence of
nodules, consolidation, ground glass opacities, emphysema, fibrosis with abnormalities marked
on the images in the PACS. Following completion of the table, the routine chest CT scan will
be used as the gold standard for the presence of the imaging findings. The documented ultra
low dose CT findings will be compared to the images from the routine chest CT scans. Each
finding documented will be individually documented as a true finding if also seen on the
routine chest CT scan or false finding if not present on the routine chest CT scan.
Additional findings only seen on the routine chest CT scan will be documented as missed
findings.