Use Of Computed Tomography Angiography Research Articles

A Comparative Observational Study of Postmortem Computed Tomography and Traditional Forensic Autopsy Findings in Hanging Cases

Background: The use of advanced radiological techniques is rising in the field of forensics to supplement and validate the evidence. Postmortem Computed Tomography (PMCT) is now used as a standard procedure in many institutions to augment traditional autopsy findings. The application of PMCT in hanging cases will greatly reduce the number of invasive traditional autopsies, as hanging is the most common method of suicide in Northern parts of India. Therefore this observational study was conducted to compare PMCT with traditional autopsy in fifty hanging cases. Result: Out of 50 cases, the age of the subjects ranged between 14 years and 70 years. PMCT with the help of 3D reconstruction was able to detect external ligature marks on the neck in 92% (N=46) of cases giving a sensitivity of 92% (CI = 80.77% to 97.78%). Skin and subcutaneous tissue desiccation were identifiable in 96% (N=48) by PMCT, giving a sensitivity of 96% (CI= 86.29% to 99.51%). The muscle hemorrhage was identified in 4% (N=2) of the cases in traditional autopsy while the authors found difficulty in interpreting the muscle hemorrhage in PMCT. In detecting thyroid cartilage fracture, the sensitivity of PMCT was found to be 100% (CI= 15.81% to 100.00%) and specificity of 100% (CI=92.60% to 100.00%). In detecting hyoid bone fracture, the sensitivity was 100% (CI= 2.50% to 100.00%), and specificity of 100% (CI=92.60% to 100.00%). In addition, there was a great degree of agreement between the two observers for these findings suggesting the reproducibility of the result. Conclusions: A consistency in findings of both the PMCT and traditional autopsy was found. However, CT was unable to detect muscle hemmorhages, compared to traditional autopsy. Authors suggest the use of CT angiography to overcome this shortcoming, till then CT can only augment invasive autopsy findings not replace it

Best Practice Recommendations for Stroke Vascular Imaging During Iodinated Contrast Shortage.

GE Healthcare© announced on April 19, 2022, that their main factory and distributor of iodinated contrast had experienced a temporary shutdown because of COVID-19 outbreak in Shanghai, China. This, along with other supply chain issues, led to a worldwide shortage of iodinated contrast agents, Omnipaque and Visipaque. Our Comprehensive Stroke Center was confronted with the cascading effect of this iodinated contrast material shortage. We took immediate steps to revise our protocols and processes to continue to provide high-quality care to our stroke patients. A multidisciplinary working group comprised of representatives of our stroke center, including vascular neurology, diagnostic neuroradiology, and neurovascular surgery, urgently met to brainstorm how to mitigate the shortage. We established parameters and local guidelines for the use of CT angiography, CT perfusion, and digital subtraction angiography for stroke patients. In this article, we propose "best practice" recommendations from a single Joint Commission approved Comprehensive Stroke Center that can be used as blueprint by other hospital systems when navigating potential future supply chain issues, to provide consistent high-quality stroke care.

Post-traumatic Pseudoaneurysm of Hepatic Artery (Case Report and Literature Review)

Pseudoaneurysm (PA) of the hepatic artery is a rare complication of abdominal trauma, iatrogenic injuries (biopsy, endoscopic cholecystectomy, liver transplantation), infections, tumors, vasculitis, acute and chronic pancreatitis. This case report presents a life-threatening complications in a patient who underwent surgery for liver lesion. Due to the use of CT angiography, it was possible to determine the cause of bleeding from the upper gastrointestinal tract, evaluation the localization of pseudoaneurysm and treated with elective management.

Virtual pathology: Reaching higher standards for noninvasive CTA tissue characterization capability by using histology as a truth standard

AimsDespite advances in therapy, reduction in myocardial infarction or death remains elusive. Whereas computed tomography angiography (CTA) is increasingly appreciated, the analyses are often subjective or qualitative. Methods for specific tissue characterization using histopathologic correlates have recently been reported. We extend this here to demonstrate accurate discrimination between, and quantitation of, lipid-rich necrotic core (LRNC), intraplaque hemorrhage (IPH), and fibrotic tissues. MethodsNCT02143102 collected 576 tissue samples with paired CTA. Cardiovascular pathologists annotated LRNC, IPH, and dense calcification (CALC) regions as a reference standard. Blinded to histology, CTA was analyzed using ElucidVivo (Elucid Bioimaging Inc., Boston, MA USA). Structure and tissue characteristics of atherosclerotic plaque from CTA, accounting for both the imaging acquisition process and the biology, accounting for differences in density distributions that result from the different cellular and molecular level milieu of the relevant tissue types. ResultsLRNC was tested across a true range of 0–10 mm2, with a difference of 0.15 mm2 and a slope of 0.92. IPH was tested across a true range of 0–18 mm2, with a difference from histology of 1.68 mm2 and a slope of 0.95. CALC was tested across a range of 0–14 mm2, with a difference of −0.06 mm2 and a slope of 0.99. Matrix tissue (MATX) was tested across a range of 4–52 mm2, with a difference of 0.02 mm2 and a slope of 0.91. ConclusionLRNC, IPH, CALC, and MATX may be objectively quantified using histopathologic correlates automatically from CTA for use singly or in combination to optimize patient care. The availability of objectively validated quantitative markers that may be followed longitudinally may extend the clinical utility of CTA. Additionally, these measures contribute efficacy variables for developing novel drugs and clinical decision support tools for tailored therapeutics.

Intracranial aneurysms mimicking third ventricular masses: case series and systematic review

ObjectiveIntracranial aneurysms presenting as third ventricular and adjoining part masses are rare and are always associated with obstructive hydrocephalus. It is vital to provide precise diagnostics and apt treatment for such patients since endovascular or microsurgical operations remain challenging. This study aimed to discuss differential diagnosis tactics based on the cases we followed and the current literature on intracranial aneurysms mimicking third ventricular masses. MethodsWe followed a case series of intracranial aneurysms presenting as third ventricular masses. Literature reports related to aneurysms adjoining the third ventricle since 1979 were systematically reviewed and summarized. ResultsTwenty-seven cases of this disease were collected. A total of 92.6% of cases developed hydrocephalus. Six cases were reported as third ventricular tumors in primary radiologic reports, and misdiagnosis hindered subsequent clinical decisions. We found a significant correlation between thrombosis and misdiagnosis, as well as between misdiagnosis and craniotomy rate. There are also false negative angiography reports for aneurysms from our cases and literature review. Strategies for the diagnosis and treatment of these aneurysms have changed over time. The uniqueness of our cases sheds light on the use of CT angiography, which has proven to be an appropriate test for diagnosis and reexamination but was not widely applied in previous reports. VW-MRI may be useful to assess rupture risk. Distinct treatment strategies show no significant difference in prognosis. ConclusionsThrombosed aneurysms should be considered as a differential diagnosis in patients with third ventricular masses. Application of CTA and VW-MRI can be beneficial. Aneurysm coil occlusion might be a favorable treatment for cases with mass effects. Further studies should be conducted to confirm our observations.

CT Marker in Emergency Imaging of Acute Basilar Artery Occlusion: Thrombosis vs. Embolism.

Purpose: Acute basilar artery occlusion, a neurovascular emergency leading to high rates of morbidity and mortality, is usually diagnosed by CT imaging. The outcome is partly dependent on etiology, with a worse outcome in occlusions with underlying basilar artery stenosis. As this occlusion type requires a more complex angiographic therapy, this study aimed to develop new CT markers in emergency admission imaging to rapidly identify underlying stenosis. Methods: A total of 213 consecutive patients (female n = 91, age in years (mean/SD/range): 72/13/28–97), who received endovascular treatment at a single comprehensive stroke center for acute basilar artery occlusion, were included in this study. After applying strict inclusion criteria for imaging analyses, novel CT imaging markers, such as ‘absolute density loss’ (ADL) and relative thrombus attenuation (CTA-index), that measure perviousness, were assessed for n = 109 patients by use of CT-angiography and correlated to different occlusion patterns (thrombotic vs. embolic). Inter-observer agreement was assessed using an intraclass correlation coefficient for independent measures of a radiologist and a neuroradiologist. Associations between the imaging markers and clinical and interventional parameters were tested. Results: CT markers differ between the subgroups of basilar artery occlusions with and without underlying stenosis (for ADL: 169 vs. 227 HU (p = 0.03), for CTA-index: 0.55 vs. 0.70 (p < 0.001)), indicating a higher perviousness in the case of stenosis. A good inter-rater agreement was observed for ADL and CTA-index measures (ICC 0.92/0.88). For the case of embolic occlusions, a more pervious thrombus correlates to shorter time intervals, longer procedure times, and worse reperfusion success (p-values < 0.05, respectively). Conclusions: ADL and CTA-index are easy to assess in the emergency setting of acute basilar artery occlusion with the use of routinely acquired CT-angiography. They show a high potential to differentiate thrombotic from embolic occlusions, with an impact on therapeutic decisions and angiographic procedures. Measurements can be quickly performed with good reliability, facilitating implementation in clinical practice.

Roles of Trauma CT and CTA in Salvaging the Threatened or Mangled Extremity.

Extremity arterial injuries account for up to 50% of all arterial traumas. The speed, accuracy, reproducibility, and close proximity of modern CT scanners to the trauma bay have led to the liberal use of CT angiography (CTA) when a limb is in ischemic jeopardy or is a potential source of life-threatening hemorrhage. The radiologist plays a critical role in the rapid communication of findings related to vessel transection and occlusion. Another role of CT that is often overlooked involves adding value to surgical planning. The following are some of the key questions addressed in this review: How does CTA help determine whether a limb is salvageable? How do concurrent multisystem injuries affect decision making? Which arterial injuries can be safely managed with observation alone? What damage control techniques are used to address compartment syndrome and hemorrhage? What options are available for definitive revascularization? Ideally, the radiologist should be familiar with the widely used Gustilo-Anderson open-fracture classification system, which was developed to prognosticate the likelihood of a functional limb salvage on the basis of soft-tissue and bone loss. When functional salvage is feasible or urgent hemorrhage control is required, communication with trauma surgeon colleagues is augmented by an understanding of the unique surgical, endovascular, and hybrid approaches available for each anatomic region of the upper and lower extremities. The radiologist should also be familiar with the common postoperative appearances of staged vascular, orthopedic, and plastic reconstructions for efficient clinically relevant reporting of potential down-range complications. Online supplemental material is available for this article. ©RSNA, 2022.

Comparison of Various Modalities Utilized for Preoperative Planning in Microsurgical Reconstructive Surgery.

The benefits of preoperative perforator imaging for microsurgical reconstruction have been well established in the literature. An extensive literature review was performed to determine the most commonly used modalities, and their applicability, advantages and disadvantages. The review demonstrated varioius findings including decreases in operative time and cost with the use of CT angiography to identification of perforators for inclusion in flap design with hand-held Doppler ultrasound. Modalities like MR angiography offer alternatives for patients with contrast allergies or renal dysfunction while maintaining a high level of clarity and fidelity. Although the use of conventional angiography has decreased due to the availability of less invasive alternatives, it continues to serve a role in the preoperative evaluation of patients for lower extremity reconstruction. Duplex ultrasonography has been of great interest recently as an inexpensive, risk free, and extraordinarily accurate diagnostic tool. Emerging technologies such as indocyanine green fluorescence angiography and dynamic infrared thermography provide real-time information about tissue vascularity and perfusion without requiring radiation exposure. This article presents an in-depth review of the various imaging modalities available to reconstructive surgeons and includes hand held Doppler ultrasound, CT angiography, MR angiography, conventional angiography, duplex ultrasonography, Indocyanine Green Fluorescence Angiography and Dynamic Infrared Thermography.

Cost Effectiveness of Computed Tomography Versus Ultrasound-Based Surveillance Following Endovascular Aortic Repair of Intact Abdominal Aortic Aneurysms

Although the Society for Vascular Surgery guidelines have recommended computed tomography (CT) angiography (CTA) or ultrasound for surveillance after endovascular aortic repair, consensus has been reached regarding the optimal timing and modalities. The differential costs, risks, and diagnostic utility of CTA, color duplex ultrasound (CDU), and contrast enhanced ultrasound (CEU) merit a cost-effectiveness analysis to estimate the outcomes of the various strategies.

Role of CT angiography in detecting acute pulmonary embolism associated with COVID-19 pneumonia

PurposeRecently coronavirus disease (COVID-19) caused a global pandemic, characterized by acute respiratory distress syndrome (ARDS). The aim of our study was to detect pulmonary embolism (PE) in patients with severe form of COVID-19 infection using pulmonary CT angiography, and its associations with clinical and laboratory parameters.MethodsFrom March to December 2020, we performed a prospective monocentric study collecting data from 374 consecutive patients with confirmed SARS-CoV-2 infection, using real-time reverse-transcriptase polymerase-chain-reaction (rRT-PCR) assay of nasopharyngeal swab specimens. We subsequently selected patients with at least two of the following inclusion criteria: (1) severe acute respiratory symptoms (such as dyspnea, persistent cough, fever > 37.5 °C, fatigue, etc.); (2) arterial oxygen saturation ≤ 93% at rest; (3) elevated D-dimer (≥ 500 ng/mL) and C-reactive protein levels (≥ 0.50 mg/dL); and (4) presence of comorbidities. A total of 63/374 (17%) patients met the inclusion criteria and underwent CT angiography during intravenous injection of iodinated contrast agent (Iomeprol 400 mgI/mL). Statistical analysis was performed using Wilcoxon rank-sum and Chi-square tests.ResultsAbout, 26/60 patients (40%) were found positive for PE at chest CT angiography. In these patients, D-dimer and CRP values were significantly higher, while a reduction in SaO2 < 93% was more common than in patients without PE (P < 0.001). Median time between illness onset and CT scan was significantly longer (15 days; P < 0.001) in patients with PE. These were more likely to be admitted to the Intensive Care Unit (19/26 vs. 11/34 patients; P < 0.001) and required mechanical ventilation more frequently than those without PE (15/26 patients vs. 9/34 patients; P < 0.001). Vascular enlargement was significantly more frequent in patients with PE than in those without (P = 0.041).ConclusionsOur results pointed out that patients affected by severe clinical features of COVID-19 associated with comorbidities and significant increase of D-dimer levels developed acute mono- or bi-lateral pulmonary embolism in 40% of cases. Therefore, the use of CT angiography rather than non-contrast CT should be considered in these patients, allowing a better evaluation, that can help the management and improve the outcomes.

Impact of H-Type Hypertension on Pericarotid Adipose Tissue and Plaque Characteristics Based on Computed Tomography (CT) Angiography: A Propensity Score Matching Study.

BackgroundWe analyzed the correlation among the inflammatory changes in pericarotid adipose tissue (PCAT), plaque characteristics, and H-type hypertension on CT angiography (CTA) and explored the utility of CTA in the prevention and treatment of carotid atherosclerosis.Material/MethodsA total of 135 patients who underwent head and neck CTA to investigate carotid artery atherosclerosis were retrospectively analyzed. The plaque characteristic parameters (plaque burden and remodeling index), PCAT attenuation value, and net enhancement value around the carotid artery, where the plaques were located, were recorded, and confounding factors were matched by propensity score analysis. A paired t test was used to compare the differences in fat tissue inflammatory changes and plaque characteristic parameters between the 2 groups, and logistic regression analysis was used to evaluate the relationship between plaque characteristics and the attenuation values and net enhancement values of PCAT. The correlation coefficient was calculated between type H hypertension and plaque risk grade.ResultsThe results of the experiment indicate that PCAT attenuation values and net enhancement values gradually increased as the degree of hypertension increased. Compared with those of patients in the normal Hcy group, these values increased more clearly in patients with high Hcy (HHcy) (r=0.641, P<0.001, r=0.581, P<0.001), although, regardless of whether the Hcy value increased, there were significant differences between the groups. However, this effect was more pronounced in patients with H-type hypertension. Logistic regression analysis of risk factors for carotid atherosclerotic plaque suggests that Hcy (OR=1.391, 95% CI 1.146–1.689, P=0.001), PCAT attenuation values (OR=1.212, 95% CI 1.074–1.367, P=0.002), and net enhancement values (OR=1.201, 95% CI 1.042–1.383, P=0.011) were independent risk factors for plaque vulnerability.ConclusionsOur results suggest that H-type hypertension is significantly associated with PCAT attenuation and net enhancement and that PCAT net enhancement values are useful in predicting plaque risk as attenuation.

Cost Effectiveness of Computed Tomography Versus Ultrasound-Based Surveillance After Endovascular Aortic Repair of Intact Abdominal Aortic Aneurysms

Although Society for Vascular Surgery guidelines recommend computed tomography angiography (CTA) or ultrasound for surveillance after endovascular aortic repair, there is a lack of consensus regarding optimal timing and modalities. The differential costs, risks, and diagnostic utility of CTA, color duplex ultrasound (CDU), and contrast-enhanced ultrasound (CEU) merit a cost-effectiveness analysis to estimate the lifetime costs and outcomes of various strategies.

P0331 - Use of CT-angiography to determine preoperative renal volume as a predictor of residual renal function in living donors

P0331 - Use of CT-angiography to determine preoperative renal volume as a predictor of residual renal function in living donors

Role of MDCT and CT Angiography in staging of pancreatic cancer

Objectives: Staging of pancreatic cancer including vascular staging by use of CT angiography with assessment of presence of direct invasion of surrounding structures or distant metastasis.Patients and Methods: In our study 50 patients with pancreatc cancer were examined with CT angiography to assessresectability and the presence or absence of vascular infiltration of 5 main peri-pancreatc vessels which are celiac artery (CA), superior mesenteric artery (SMA), common hepatic artery (CHA), superior mesenteric vein ( SMV) and portal vein (PV). We assessed five vessels in fifty patientsi.e two hundred and fifty vessels as a whole.Results: Twenty four patients were pre-operatively judged to be resectable or requiring surgical bypass due to jaundice. The remaining 26 patients were judged to be irresectable from the start and referred for chemotherapy or radio-therapy.Conclusion:CT angiography proved to be an important tool in assessing intra abdominal malignancy specially the cancer of the pancreas which in most of cases is missed by abdominal ultrasonography.

Pulmonary vein stenosis after lung transplantation: a case report and literature review

Pulmonary vein stenosis (PVS) is a rare event following lung transplantation which increases the risk of morbidity and mortality. Early detection and rapid treatment of this condition is crucial for its management. Although several reports on PVS have been published, there is little consensus regarding its diagnosis and the methods of management. Here we present our experience with PVS. A 31-year-old man received a left lung transplant for chronic hypersensitivity pneumonitis. One year after his single-lung transplant, he began to develop persistent progressive hypoxemia. Computed tomography (CT) of the chest showed left pleural effusion and thickening of the interlobular septa. The results of bronchoscopy and transbronchial biopsies excluded the possibility of acute rejection or infection. The pleural effusion was transudative with lymphocyte predominance. Computed tomography angiography (CTA) in the left atrium and pulmonary veins demonstrated obvious stenosis of both the upper and lower left pulmonary veins (LLPVs) at the transplant anastomotic site. The patient underwent a catheter-guide stent implantation into the stenotic segment of the upper left pulmonary vein (ULPV), and his pleural effusion and hypoxemia problems were ameliorated. Ten months after the intervention, the patient was in excellent clinical condition. In a literature review, we discuss the importance of identifying PVS early after transplantation, the utility of CTA for diagnosis and the use of pulmonary vein stenting intervention. This review provides a basis for further diagnostic strategies and treatments for PVS following lung transplantation.

Management of Postpancreatectomy Hemorrhage Following Pancreaticoduodenectomy at a Tertiary Care Center in Nepal

Introduction Postpancreatectomy hemorrhage (PPH) is an important complication which significantly increases morbidity and mortality following pancreaticoduodenectomy (PD). This study aims to find the incidence, classification, management, and mortality associated with PPH following PD. This study also describes the changes in management and outcomes between the period of 2004-2014 and 2015-2019 in our institute as in the later time period there was use of CT angiography and interventional radiology (IR) to identify and control the bleeding site.&#x0D; MethodsThis is a retrospective study in which medical records of patients having PPH following PD between 2004-2019 were analyzed. The grading and classification were done according to the International Study Group of Pancreatic Surgery (ISGPS). Management and outcomes were analyzed using standard descriptive statistics.&#x0D; ResultsA total of 43 patients developed PPH out of 336 PDs. Out of 43 patients, 4 (9.3%) had Grade A, 16 (37.2%) had Grade B and 23 (53.5%) had Grade C PPH. Fifteen (35%) patients were managed conservatively, seven (16.2%) with IR procedure and 21 (48.8%) were reexplored. There were 16 (37.2%) mortalities, out of different factors- intraoperative blood loss &gt;500 ml showed the predictability for mortality (p= 0.01). On comparing two time periods it was seen that the PPH rate was almost similar but the mortality decreased from 58.8% to 23.07%.&#x0D; ConclusionPPH following PD is associated with high mortality. Increased use of IR procedure and CT angiography can decrease the relaparotomy rates and eventually decrease mortality.

Management of Postpancreatectomy Hemorrhage Following Pancreaticoduodenectomy at a Tertiary Care Center in Nepal

Introduction: Postpancreatectomy hemorrhage (PPH) is an important complication which significantly increases morbidity and mortality following pancreaticoduodenectomy (PD). This study aims to find the incidence, classification, management, and mortality associated with PPH following PD. This study also describes the changes in management and outcomes between the period of 2004-2014 and 2015-2019 in our institute as in the later time period there was use of CT angiography and interventional radiology (IR) to identify and control the bleeding site. Methods: This is a retrospective study in which medical records of patients having PPH following PD between 2004-2019 were analyzed. The grading and classification were done according to the International Study Group of Pancreatic Surgery (ISGPS). Management and outcomes were analyzed using standard descriptive statistics. Results: A total of 43 patients developed PPH out of 336 PDs. Out of 43 patients, 4 (9.3%) had Grade A, 16 (37.2%) had Grade B and 23 (53.5%) had Grade C PPH. Fifteen (35%) patients were managed conservatively, seven (16.2%) with IR procedure and 21 (48.8%) were reexplored. There were 16 (37.2%) mortalities, out of different factors- intraoperative blood loss &gt;500 ml showed the predictability for mortality (p= 0.01). On comparing two time periods it was seen that the PPH rate was almost similar but the mortality decreased from 58.8% to 23.07%. Conclusion: PPH following PD is associated with high mortality. Increased use of IR procedure and CT angiography can decrease the relaparotomy rates and eventually decrease mortality.

ACR Appropriateness Criteria Facilitate Judicious Use of CT Angiography for Stroke Workup in the Emergency Department

CT angiography (CTA) of the head and neck plays a key role in the evaluation of patients with stroke in the emergency department, particularly to evaluate for large-vessel occlusion and consider patients for mechanical thrombectomy. However, CTA is not always indicated and has various costs. The aim of this study was to examine the correlation between ACR imaging appropriateness recommendations and findings explanatory for stroke on CTA of the head and neck. CTA head and neck examinations of emergency department patients performed to evaluate for stroke between January 1, 2019, and June 30, 2019, were retrospectively reviewed. Patients with previously known acute infarct, with primary concern for or discovered hemorrhage, or being evaluated for trauma were excluded. Presenting symptoms were classified on the basis of the most recent ACR Appropriateness Criteria, into three categories: "usually appropriate" (UA), "may be appropriate" (MBA), or "usually not appropriate" (UNA). The percentage of examinations with findings explanatory for stroke were compared among the three groups using the Fisher exact test. A total of 707 cases were reviewed, of which 317 were included; 199 fell into the UA category, 38 MBA, and 80 UNA. For UA, 57 of 199 CTAs (29%) had findings explanatory for stroke, compared with 1 of 38 (3%) in the MBA group (difference, 26%; 95% confidence interval, 13%-34%; P < .001) and 1 of 80 (1%) in the UNA group (difference, 27%; 95% confidence interval, 19%-35%; P < .001). ACR Appropriateness Criteria recommendations correlate with imaging findings explanatory for stroke and may guide the judicious use of CTA for suspected stroke workup.

ORGAN EQUIVALENT DOSE AND LIFETIME ATTRIBUTABLE RISK OF CANCER INCIDENCE AND MORTALITY ASSOCIATED WITH CARDIAC CT ANGIOGRAPHY.

The aim of this study is the calculation of equivalent organ dose and estimation of lifetime attributable risk (LAR) of cancer incidence and mortality related to cardiac computed tomography angiography (CCTA) because the use of CT angiography as a noninvasive diagnostic method has increased. The organ dose has been calculated by ImPACT software based on the volumetric CT dose index (CTDIvol), and LAR of cancer risk incidence and mortality from CCTA has estimated according to the BEIR VII report. The median value of the effective dose was 13.78±6.88mSv for both genders. In all scanners, the highest median value for LAR of cancer incidence in males and females for lung cancer was 44.20 and 109.17 per 100 000, respectively. And in infants was 5.89 and 12 for lung cancer in males and breast cancer in females, respectively. Also, the median value of LAR of all cancer incidence from single CCTA in adult patients for males and females was 122 and 238 cases, respectively. Maximum LAR of cancer mortality in adults for lung cancer was 40.28 and 91.84 and in pediatrics was 5.69 and 8.50 in males and females, respectively. Despite many benefits of CTA in the heart disease evaluation, according to a high radiation dose in CCTA, to reduce the cancer risk: CCTA should be used cautiously, especially for pediatric and females.

Abstract WP289: Increasing Emergency Department Use of Advanced Neuroimaging in the Mechanical Thrombectomy Era

Introduction: Data supporting mechanical thrombectomy substantially expanded both the time available for treatment and need for advanced neuroimaging in patients with suspected stroke. These factors potentially increase emergency department (ED) use of neuroimaging resources, though the existence and magnitude of effect is unknown, particularly in a broad hospital population including non-stroke center emergency departments. Hypothesis: ED use of CT-angiography (CTA) and CT-Perfusion (CTP) imaging is both increasing and accelerating from 2013 to 2018. Methods: Prospective, longitudinal, single-state cohort study of ED visits using existing California OSHPD dataset (a mandatory reporting database of all CA-licensed, non-federal, emergency department encounters either discharged or transferred) from 2013 to 2018. NCHCT (CPT 70450), CTA Head (CPT 70496), CTP (CPT 0042T) and MRI Brain (CPT 70553) use in the data set, as determined by Common Procedural Terminology (CPT) codes, was analyzed using descriptive statistics and tests of comparison. Results: All advanced neuroimaging increased during the period. Use of NCHCT increased 61% over the study period, from 2,432 to 3,922 per 100,000 ED visits (p trend &lt; .001). Use of CTA increased 405%, from 39 to 197 per 100,000 encounters (p trend &lt; .001). Use of CTP increased 230%, from 3 to 10 per 100,000 encounters (p trend &lt; .001). Use of MRI Brain increased 19%, from 52 to 62 per 100,000 encounters (p trend &lt; .001). On a year-over-year basis, both CTA and CTP use is accelerating, with substantial increases noted between 2017 and 2018. Conclusions: We identified recent, substantial, temporal changes in CTA and CTP neuroimaging acquisition among CA emergency departments in the nascent mechanical thrombectomy era. Dramatic changes in CTA and CTP use suggest that changes are occurring in ED evaluation of neurological emergencies. If true, this differs substantially from the speed of ED acceptance of rt-PA for stroke treatment. Further analysis from the CA OSHPD and other (NEDS) datasets is planned to better understand the patient, hospital, and clinical factors driving these neuroimaging trends in the ED.