In 2010, the alliance for quality computed tomography working group was formed to provide information to ct users that enhances the quality of their ct practice. Retrospective analysis was performed of 50 consecutive patients with proven nsclc who had been referred for primary staging n41 or restaging n9. Lowdose techniques in ctguided interventions radiographics. Comparison of lowdose ct with adaptive statistical iterative reconstruction and routinedose ct with filtered. Although there are several studies that assess the efficacy of low dose ct protocols for various purposes, the evidence that standard dose ct protocols can be routinely substituted for by low dose ct is lacking. The image spacing or reconstruction interval was 1 mm, and. By comparison, the radiation exposure from one lowdose ct scan of the chest 1. They are easily seen on low dose ct protocols against well mineralized trabecular bone, although in some patients with marked osteoporosis they may be difficult to discriminate from areas with. Indications for screening as screening is for asymptomatic persons, documentation of the symptom profile is needed. Wholebody lowdose computed tomography and advanced imaging. Weightbased, lowdose pediatric wholebody petct protocols. The implementation of ultra low dose ct protocols in petct pf wojtylak 2, an crisan 2, n ralph 2, a sher 1,2, j vercherconejero 1, a kohan 1 and jk odonnell 1,2 division of nuclear.
In the henschke study, only patients with certain findings on low dose ct were recommended to have high dose ct. Mcintosh do, mph university of massachusetts medical center. Weightbased, lowdose pediatric wholebody petct protocols adam m. Low dose ct examinations are currently employed to detect lung nodules and to find treatable lung cancer cases.
Image quality of routine and low dose protocols in comparison with standard filtered backprojection a. Significance of ct scan protocol ct equipment outputcalibration routinely evaluated regulations andor physics practice however scanners themselves are typically very stable and ct console reported dose metrics generally quite accurate. The low dose spiral ct scan continuously rotates in a spiral motion and takes several 3dimensional xrays of the lungs. Parisi1,2 1department of radiology, university of washington, seattle, washington. Low dose chest ct protocol at 50 mas may be substituted for standard dose ct with 150 mas, not only for the detection of lesion, but also characterization. Comparison of ultralow dose chest ct scanning protocols for the. Ir has recently demonstrated its capacity to reduce noise and. The result of this study shows that low dose ct images acquired with current time product of 50 mas offers the tumor characterization capability comparable to that of standard dose ct images. Very lowdose scanning uses about th the amount of radiation as a regular ct scan. Chest, abdomen and pelvis ct protocols chest chest ct low dose nodule evaluation chest ct lung cancer screening chest ct routine with contrast chest ct without routine chest cta pulmonary embolism chest cta acute aorta chest cta aortic aneurysm pre evt chest cta aortic aneurysm post evt chest cta acute aorta trauma chest ct high resolution. The risk of radiationinduced cancer death for one standard chest ct is estimated at roughly one in 3000, and could be reduced hypothetically. Lowdose ct lends itself well to thoracic imaging, partly due to the high inherent tissue contrast in the lungs. To develop low dose protocols, it is important to understand the key concepts of delivered radiation dose to patients and physicians during ct guided interventions. Alessio, phd university of washington, seattle, wa paul e.
The low dose protocols can be used when reduced image quality is acceptable for the purpose of the study, such as followup studies. Lowdose ct in the abdomen and pelvis is challenging due to similar densities of adjacent structures and little difference between the attenuations of normal and pathological processes that can be easily obscured by increased image noise in the lowdose setting. The slice thickness was 1 mm with a table feed of 2 mm pitch 2. Kinahan1, vivek manchanda1,2, victor ghioni2, lisa aldape2, and marguerite t. Pdf image quality and radiation exposure using different. You will have one regular ct scan and one ultra low dose ct scan. Contribution of lowdose ctscan protocols to the total. Lowdose ct computed tomography ct is an imaging test used to create images of internal organs, bones, soft tissue and blood vessels. Annual lowdose ct scans could save you from lung cancer. The images generated during a ct scan are used to generate threedimensional images and are often the best method for detecting different cancers. Increasing the awareness and the understanding of ct radiation dose issues among doctors and technologists will lead to improvement of scan protocols and therefore reduce radiation dose. Recommendations for acquisition, interpretation and. Comparison of radiation dose estimates, image noise, and scan duration in pediatric body imaging for volumetric and helical modes on 320detector ct and helical mode on 64detector ct. By comparison, the radiation exposure from one low dose ct scan of the chest 1.
Assessing imaging scan protocol peter gianakopoulos md, phd, radiology resident pgy2. The exposure dose received during acquisition of three or four low dose chest ct scans is equivalent to that received during acquisition of one routine chest ct scan. There is no specific definition of lowdose, although historically most screening protocols have used scan parameters of 120140 kvp and 30100 mas. Scanning and reconstruction protocols for lowdose ct lung cancer screening 1 singleslice ct the scanning protocol used for single slice ct are 120140 kvp, 2050 mas, collimation 10 mm, and helical pitch 2. Apr 27, 2016 although there are several studies that assess the efficacy of low dose ct protocols for various purposes, the evidence that standard dose ct protocols can be routinely substituted for by low dose ct is lacking. Practice parameters and technical standards are not inflexible rules or requirements of practice and are. A lowdose ct scan can detect earlystage lung cancer before symptoms arise, when the disease is more curable. Computed tomography ct is a radiologic modality that utilizes ionizing radiation to obtain crosssectional. The scan field of view should be optimized for each patient. Ct imaging plays an important role in the diagnosis of covid2019. To help answer those questions we have put together our protocols as well as adding ct scan protocols from other institutions that we thought might prove useful.
Prior to the ct scan, for clinical evaluation you will have blood work, a chest xray, pulmonary function tests, a history and physical, and urine testing. The exposure dose received during acquisition of three or four lowdose chest ct scans is equivalent to that received during acquisition of one routine chest ct scan. Pdf download for comparison of ultralow dose chest ct scanning. Kinahan, phd university of washington, seattle, wa computed tomography ct acquisition during positron emission tomography petct imaging is often performed for a variety of purposes. Recent efforts have focused on ct dose modification in an effort to prevent unwanted longterm health effects e.
Comparison of low dose ct with adaptive statistical iterative reconstruction and routine dose ct with filtered. Currently smoke or have quit within the past 15 years, and. Low dose ct is much more effective as a screening process than chest xray, but the drawback is that low dose ct examinations uncover many nodules or larger localized lesion which should be differentiated from lung cancers. Image quality and radiation exposure using different lowdose. Although there are several studies that assess the efficacy of lowdose ct protocols for various purposes, the evidence that standarddose ct protocols can be routinely substituted for by lowdose ct is lacking. Scan range apex to adrenals apex to adrenals rotation time 0. The type of lowdose ct scan that is recommended for lung cancer screening is a newer form of ct scan known as a lowdose spiral or helical ct scan. The ct scan was performed as a spiral scan on a ge hispeed advantage system ge medical systems, milwaukee, usa using a low dose scan protocol as described by heermann and lenarz3. Lowdose ct lung cancer screening guidelines for pulmonary nodules management version 2 the committee for management of ctscreeningdetected pulmonary nodules 20092011 the japanese society of ct screening a pulmonary nodule is defined as a rounded or irregular opacity, well or poorly defined, measuring up to 3 cm in diameter 1. We implemented a lowdose scanning protocol that reduced the. Clinical information will be shared with you and if you wish, your doctor. They are easily seen on low dose ct protocols against well mineralized trabecular bone, although in some patients with marked osteoporosis they. The scanning protocol used for single slice ct are 120140 kvp.
Recommendations for acquisition, interpretation and reporting. Lowdose computed tomography for the optimization of. The american cancer society recommends annual lung cancer screening with a lowdose ct scan ldct for certain people at higher risk for lung cancer who meet the following conditions. Ct protocols for common primary care diagnoses lacey j. General considerations regarding ct dose reduction. Simple ct techniques to reduce radiation dose may be employed without increasing the procedure time or significantly degrading image quality. Ct scanning ct protocols ctisus ct scan, protocols. Ge 64 routine chest ct scan type helical helical scan range apex to adrenals apex to adrenals. To facilitate the use of low dose chest ct, adequacy of a low dose ct protocol as a routine protocol needs to be confirmed. The effective radiation dose saved per patient assumed 1 wide volume boxintervertebral level and site standardization. Ct protocol selection in petct imaging image wisely. Ct imaging increasingly relies on the integration of a variety of knowledge and skills. Recommendation of lowdose ct in the detection and management.
Kinahan, phd university of washington, seattle, wa computed tomography ct acquisition during positron emission tomography pet ct imaging is often performed for a variety of purposes. The general dose education slides are available as a powerpoint or pdf file and contains vendorindependent information on ct acquisition parameters, dose modulation and reduction and dose display. Diluted omnipaque 240 for peds and omnipaque 240300 for adults po for ct scan. Computed tomography ct of the abdomen and computed tomography ct of the pelvis preamble this document is an educational tool designed to assist practitioners in providing appropriate radiologic care for patients.
Wholebody lowdose computed tomography and advanced. Lowdose ct scan for lung cancer screening swedish medical. At skg radiology, we guarantee we will utilise alara as low as reasonably achievable radiation protocols in conjunction with market leading ct dose reduction. We also enhance the ct protocols with select instructive cases. Low dose nodule fu high resolution for interstitial lung disease. To evaluate low dose nonenhanced ct and standard dose contrastenhanced ct in combined petct protocols for staging and therapy planning of nonsmall cell lung cancer nsclc. For optimal image quality and proper operation of the smart ma. The ctscan was performed as a spiral scan on a ge hispeed advantage system ge medical systems, milwaukee, usa using a lowdose scan protocol as described by heermann and lenarz3. We hope you find this useful and would appreciate any. Image quality and radiation exposure using different low.
The low dose protocols provide onehalf the dose of the standard protocols. To develop lowdose protocols, it is important to understand the key concepts of delivered radiation dose to patients and physicians during ctguided interventions. Researchers at the national institutes of health nih are studying if low dose ct scans are as effective as regular ct scans to monitor your disease status. Implementation of low dose ct protocols sign in or create an. The low dose ct scan is also suitable for special populations such as pediatric patients and pregnant women because of the decreased risk of longterm adverse effects. Kalra, md, dnb massachusetts general hospital harvard medical school.
The only recommended screening test for lung cancer is low dose computed tomography also called a low dose ct scan, or ldct. Changes from revision 2 to revision 3 as part of our ongoing uw madison ct protocol optimization, we have made the following changes between the revision 2 and revision 3 release. It begins with the initial lowdose ct scan at baseline and continues with repeat. Radiation exposure during chest ct is estimated at 7 msv 1.
Lowdose ct lung cancer screening guidelines for pulmonary. Pdf the implementation of ultralow dose ct protocols in. In conclusion, the correct selection of a lowdose ct coronary angiographic scan protocol with use of a 128section dualsource ct scanner results in a significantly lower radiation dose and comparable image quality compared with those of previously established ct coronary angiographic scan protocols. Aapm ct scan protocols the alliance for quality computed. Image quality of routine and lowdose protocols in comparison with standard filtered backprojection a. The purpose of this study was to compare image quality of two different abdominal ct protocols in the same abdominal ct. Low dose chest ct protocol 50 mas as a routine protocol for. Pdf the implementation of ultralow dose ct protocols. Low dose ct computed tomography ct is an imaging test used to create images of internal organs, bones, soft tissue and blood vessels. Scans should generally be obtained during suspended respiration but may be obtained. Computed tomography ct scans and cancer fact sheet. The only recommended screening test for lung cancer is lowdose computed tomography also called a lowdose ct scan, or ldct. A geometrically accurate imaging is required with a low level of noise and balanced ct dose to image quality.
The membership includes academic and consulting medical physicists who specialize in ct imaging, representatives of each of the major ct scanner manufacturers, and liaisons to the. Are aged 55 to 74 years and in fairly good health, and. Ct examinations account for majority of radiation exposure related to medical imaging 1, 2. That is, an independent, blind, comparison of the lowdose ct tests with a gold standard e.
During an ldct scan, you lie on a table and an xray machine uses a low dose amount of radiation to make detailed images of your lungs. Mcintosh do, mph university of massachusetts medical center unecom 2014 cme programreunion and alumni weekend. Acrspr practice parameter for the performance of computed. Scanning and reconstruction protocols for lowdose ct lung cancer screening. To compare image quality, radiation dose, and their relationship with heart rate of computed tomographic ct coronary angiographic scan protocols by using a 128section dualsource ct scanner. Salient points in chest ct protocols lung nodule fu ct. Novel wholebody low dose computed tomography wbldct protocols allow for collection of superior image detail of the skeleton at doses of radiation similar to those used for conventional planar radiography. Feb 25, 2020 you will have one regular ct scan and one ultra low dose ct scan. The lowdose ct scan is also suitable for special populations such as pediatric patients and pregnant women because of the decreased risk of longterm adverse effects. The lowdose spiral ct scan continuously rotates in a spiral motion and takes several 3dimensional xrays of the lungs. There are also no studies comparing the diagnostic accuracy. The entire slide set or pieces of it may be incorporated into any educational presentation as the user sees fit. In adults, 120 kv is generally used, while 140 kv may be needed in very large adults to provide enough xray output and penetration to produce a clinically acceptable image that is not too noisy. Low dose chest ct protocol 50 mas as a routine protocol.
Ct offer superior detection of myeloma bone disease and extramedullary manifestations of plasma cell dyscrasias. In the henschke study, only patients with certain findings on lowdose ct were recommended to have highdose ct. New pediatric protocols a tutorial frank ranallo, ph. Helical or spiral scan type is the predominan t type of scan for all types of protocols. The fi rst three sections of this text provide information on physics, patient care, and crosssectional anatomy necessary to understand. Two chest ct scans were performed with current time product of 50 and 150 mas at 120 kvp, with the same scan length with a 16 detectorrow ct scanner. Previous studies have shown the usefulness of lowdose ct protocols in the evaluation of pathologic processes throughout the body. Protocols for lumbar spine imaging across hospital sites are. In conclusion, the correct selection of a low dose ct coronary angiographic scan protocol with use of a 128section dualsource ct scanner results in a significantly lower radiation dose and comparable image quality compared with those of previously established ct coronary angiographic scan protocols.
264 1564 1062 817 839 874 41 1065 862 1103 918 1570 488 1005 245 522 1447 1436 1252 95 1563 1499 431 539 693 1396 867 1142 693 206 213 1077 313 660 944 887 732 450