Non-contrast CT Scan Research Articles

Closed bowel loop obstruction by a fibrous band mimicking paraduodenal hernia

Abstract Background A closed-loop obstruction occurs when a section of the intestine becomes blocked at two locations along its pathway, increasing the likelihood of volvulus and ischemia. Frequently, a single adhesive band is the primary cause of a closed loop, although internal hernias from congenital defects or iatrogenic intervention in the mesentery or omentum can also become other factors. In closed-loop obstruction, computed tomography (CT) often displays a distinctive pattern where the bowel appears dilated and filled with fluid, forming a ‘C-shaped’ configuration. Case presentation A 43-year-old female patient presented to the emergency department complaining of acute abdominal pain and repeated bilious vomiting with no history of absolute constipation. By examination, there were tenderness, guarding and rigidity. Her medical history includes type 1 diabetes since the age of 9 years and her surgical history included a onetime cesarean section and negative history of laparoscopic interventions. Ultrasound was done as a first-line investigation. It showed a few dilated bowel loops in addition to moderate intraperitoneal free fluid and could not detect the cause of bowel dilatation; therefore, non-contrast CT scan was requested and revealed the following findings: Two bowel loops exhibited distension and mucosal edema, and the configuration of bowel loops resembled a distinctive C-shape. Conclusion Distinguishing between adhesive small bowel obstruction (SBO) and paraduodenal hernia relies on clinical history, imaging features, and risk factors. Adhesive SBO often stems from prior surgery or inflammation and may exhibit ‘beak’ or ‘whorl’ signs on CT scans.

Investigation Into the Effects of Intra-Articular Steroid on Post-Traumatic Osteoarthritis in Distal Radius Fractures: A Randomized Controlled Pilot Study

The aim of this prospective, randomized, controlled, double-blinded pilot study was to determine the rates of post-traumatic osteoarthritis and assess joint space width in the presence or absence of a single intra-articular injection of corticosteroid after an acute, intra-articular distal radius fracture (DRF). Forty patients received a single, intra-articular, radiocarpal joint injection of 4 mg of dexamethasone (DEX) (n= 19) or normal saline placebo (n= 21) within 2 weeks of a surgically or nonsurgically treated intra-articular DRF. The primary outcome measure was minimum radiocarpal joint space width (mJSW) on noncontrast computed tomography scans at 2 years postinjection. Secondary outcomes were obtained at 3 months, 6 months, 1 year, and 2 years postinjection and included Disabilities of the Arm, Shoulder, and Hand; Michigan Hand Questionnaire; Patient-Rated Wrist Evaluation; wrist range of motion; and grip strength. At 2-year follow-up, there was no difference in mean mJSW between the DEX group (2.2 mm; standard deviation, 0.6; range, 1.4-3.2) and the placebo group (2.3 mm; standard deviation, 0.7; range, 0.9-3.9). Further, there were no differences in any secondary outcome measures at any postinjection follow-up interval. Radiocarpal joint injection of corticosteroid within 2 weeks of an intra-articular DRF does not appear to affect the development of post-traumatic osteoarthritis within 2 years follow-up in a small pilot cohort. Therapeutic II.

The relationship between lung cancer and hepatosteatosis in patients with biopsy-confirmed lung cancer diagnosis.

The purpose of this study is to evaluate whether hepatosteatosis is associated with lung cancer in patients undergoing lung nodule biopsy. 359 patients (248 males, 69.1%) who underwent lung biopsy between the years 2016 and 2022 were included in this retrospective study. The average age of the patients was 64.59±14.05 (range=30-90) years. These patients were undergoing follow-up for a lung lesion and had undergone thoraco-abdominal CT scans. Attenuation measurements were performed on non-contrast CT scans from the liver and spleen parenchyma. Pathology results showed that the majority of diagnoses were malignant (n=265, 73.8%). Statistical analysis revealed a significantly higher number of patients with malignancy among those with hepatosteatosis compared to those without hepatosteatosis (73% vs. 57%, p=0.006). Furthermore, patients with malignancy were more frequently male (73 vs. 27%, p=0.010), older (65.80±12.83 years vs. 61.20±16.63 years; p=0.06) and had a higher prevalence of diabetes mellitus (DM) (43.7 vs. 31.9%, p=0.046). Logistic regression analysis indicated that advanced age, DM, and hepatosteatosis were associated with an increased risk of malignancy (p=0.049, 95% CI (1.000-1.036), p=0.044, 95% CI (0.0347-0.98736), p=0.013, 95% CI (1.154-3.323), respectively). The study findings suggest that hepatosteatosis might be associated with lung cancer. Therefore, due to its possible relationship with lung cancer, it should be taken very seriously, considering the chance of early diagnosis and treatment.

Computed tomography-guided frame-based stereotactic brain biopsy of non-enhancing lesions using indirect evidence of target selection, technical consideration, and early clinical experience.

The objective was to study the effectiveness and diagnostic outcome of frame-based stereotactic brain biopsy (STB) done for contrast non-enhancing lesions using indirect evidence of target selection observed in a plain computed tomography (CT) scan of the head. Data of patients with contrast non-enhancing brain lesions who underwent STB are collected retrospectively from NIMHANS Bangalore, hospital neurosurgery database from January 2021 to March 2023. Those cases subjected to plain CT scans after fixing the stereotactic frame to the head were included in the study. A final histopathological report analysis of these cases was done to assess the diagnostic accuracy. A total of 27 such cases were biopsied. The mean age of subjects was 44.04 ± 17.812 years. Most subjects were in the age group 31-40 years (29.6%). About 55.6% were male and 44.4% were female. The most common site of biopsy was the frontal lobe. The most common indirect evidence on CT was perilesional edema at 33.3% and periventricular location at 33.3%, followed by intralesional calcification at 11.1%. Our diagnostic accuracy was 92.59%. The asymptomatic hemorrhage rate was 2%, and an increase in perilesional edema was seen in 2% of cases. Indirect targeting is a safe and intuitive method for biopsy of contrast non-enhancing lesions. Due consideration is to be given to various findings visible in non-contrast CT scans of the head as indirect evidence of target selection while performing frame-based STB of contrast non-enhancing lesions. This method will also be helpful in resource-limited centers, especially in low-income countries.

Inguinal Arteriovenous Malformation

Arteriovenous malformations (AVMs) are rare disorders, with inguinal region involvement being particularly uncommon, as they typically manifest in the neck, limbs, trunk, and intracranial or extracranial sites. Despite their varied presentation across organs and tissues, AVMs can lead to cardiac failures due to high output, necessitating management even in asymptomatic cases. We present the case of a 37-year-old male with a known history of hypertension and severe depressive disorder, referred to the urology department for bilateral renal calculi evaluation. The patient complained of sudden-onset, moderate-intensity left-sided flank pain, with no signs of infection or constitutional symptoms. A non-contrast CT scan revealed bilateral renal calculi and an intriguing mass in the scroto-inguinal region. Further investigation through contrast-enhanced computed tomography identified an AVM originating from the right internal iliac artery, located a few millimeters next to the scrotum. A multidisciplinary team, including interventional radiology, urology, and vascular surgery, collaborated to develop a curative strategy. Angioembolization was performed successfully in a single session, involving catheterization and ligation of the feeder vessel using a lipiodol-glue mixture. Postoperatively, the patient remained stable with mild pyrexia (99°F), a heart rate of 76 bpm, and blood pressure fluctuating between 110-125 mmHg systolic and 72-80 mmHg diastolic. The absence of glue leakage upon saline injection confirmed the effectiveness of embolization. The patient experienced relief from pain and was mobilized on the second postoperative day. This case underscores the importance of a comprehensive approach in managing rare presentations of AVMs, emphasizing successful angioembolization as a viable therapeutic option

High Incidence Rate of Computed Tomography-Measured Steatotic Liver Disease in Men With and Without HIV Infection.

We determined steatotic liver disease (SLD) incidence in a prospective cohort of men with HIV (MWH) and men without HIV (MWOH). Incident SLD was defined using paired noncontrast computed tomography scans performed during 2010-2013 and repeated during 2015-2017. Of 268 men, 173 MWH and 95 MWOH, 33 had incident SLD (11.1%, incidence rate 2.4 and 2.7/100 person-years for MWH and MWOH, respectively). Overall, higher abdominal visceral adipose tissue was independently associated with increased SLD risk. In MWH, increased visceral adipose tissue, insulin resistance, chronic hepatitis B, and cumulative etravirine use were associated with SLD. Metabolic factors, but not HIV, were associated with incident SLD. The high incidence rate suggests that SLD will continue to increase in PWH.

Cerebral Abscess In A Child With Unknown Origin Of Infection

Introduction: The incidence of brain abscesses is higher in developing countries. The classic triad of fever, headache, and focal neurological signs was seen in 9–28% of the pediatric cases. Brain abscesses occur infrequently with potentially life-threatening conditions. Case Report: The patient was a child 1 year 8 months old with a main complaint of weakness in the left arm and leg progressively for one month. She had a local seizure on her left arm and leg one month before admission with a duration of 30 minutes. She was irritable for the last two weeks. The strength of the upper and lower extremities was 3 respectively. The physiology reflex was hyper-reflex on the upper and lower extremities. A Head non-contrast CT scan showed a hypodense lesion on the right parietal with a perifocal edema lesion. A head contrast CT scan showed a hypodense lesion on the right parietal with ring enhancement measuring approximately 6,2 cm x 4,5 cm. Craniotomy evacuation abscess with near total capsulectomy was done on initial and capsule resection was done. Discussion: Brain abscess is a focal pyogenic infection of the brain parenchyma, and the frontotemporal lobe is the most common site of brain abscess, followed by frontal-parietal, parietal, occipital lobes, and cerebellar. The most common risk factors that predispose a child to the formation of a brain abscess include congenital heart disease, sinus and otogenic infections, and poor dental hygiene. The triad of brain abscess, including headache, fever, and neurological symptoms is only present in (15%) of the cases reported. Medical treatment is recommended in patients without increased intracranial pressure, with symptoms of less than 1 week long and abscess of less than 2 cm seen in tomography. The suggested time of treatment is between 6 and 8 weeks with intravenously administered antibiotics. A full recovery rate from the infection of about 60–70% is reported in the case of early diagnosis and proper therapy Conclusion: Cerebral abscess in pediatrics with unknown origin of infection may happen in 12%. Early diagnosis and treatment of pediatric cerebral abscesses can reduce morbidity and mortality rates. A broadspectrum antibiotic is an optimal treatment in the postoperative evacuation of cerebral abscess cases with unknown origin infection.

Role of non-contrast CT component of prostate-specific membrane antigen PET/CT scan in the detection of peripheral zone prostate cancer.

The aim of this study was to look for feasibility of non-contrast CT (NCCT) in detecting peripheral zone prostate cancer (PCa). A retrospective analysis included 50 biopsy-proven PCa patients between April 2019 and March 2022 who underwent staging whole body prostate-specific membrane antigen (PSMA)/CT prior to treatment. The control subjects were 50 randomly selected adult male patients who underwent PET/CT for non-prostate malignancy during the same time period. Two readers independently calculated the Hounsfield unit (HU) of normal peripheral zone, central zone, and corresponding PSMA avid focus in cases. No significant difference was seen in the mean HU value of normal peripheral zone between cases and controls. Significant difference in the mean HU was seen between the PSMA avid focus in cases (40.1 ± 6.2) and normal peripheral zone of cases (28.2 ± 7.0) and controls (27.7 ± 5.8). No significant difference was found between the mean HU values of high-grade PCa and non-high-grade PCa. Receiver operating characteristic (ROC) curve analysis revealed a mean HU cut-off of ≥35 for detecting PCa with a sensitivity and specificity of 86% and 90%, respectively, between cases and controls (AUC 0.88). Detection of clinically significant PCa is possible on routinely performed NCCT scans. Radiologists should routinely look for and convey these findings to facilitate further work-up and early detection of PCa. Our study adds to the knowledge that NCCT scans performed for unrelated indications can serve as a screening tool for clinically significant PCa.

The Impact of Semaglutide on Liver Fat Assessed by Serial Cardiac CT scans in Patients with Type 2 Diabetes: Results from STOP Trial

IntroductionThere is increasing prevalence of hepatic steatosis. Hepatic steatosis is increasingly recognized as the independent risk factor for cardiovascular mortality. However, there are limited options for the treatment of fatty liver. In this study we evaluated the effect of semaglutide on liver fat as measured by non-contrast cardiac CT scans. MethodsSTOP is a randomized controlled trial that evaluated semaglutide treatment effect on coronary atherosclerosis progression (STOP) in type 2 diabetes. We utilized unenhanced cardiac CT scans to quantify liver fat based on CT Hounsfield attenuation method. A total of 114 subjects qualified for this study of the 140 subjects randomized, 59 in semaglutide group and 55 in the placebo group and were followed for 12 months. Multivariate regression models were used to evaluate the change in liver fat content overtime. Results114 subjects were included in the study, 61% male, mean age of 57.8±8.1 years and mean BMI of 32.0±6.7. The average of the three liver measures showed an improvement in the semaglutide group 1.4±9.0 versus worsening in the placebo group of 1.9±9.5 mean HU. The multivariable linear regression models including age, gender, BMI, hypertension, hyperlipidemia, past smoking and baseline liver attenuation, showed that the semaglutide group average liver attenuation measures improved by 4.4 HU versus placebo across the trial, p=0.002 indicating improvement in the liver fat content in treatment group. ConclusionIn type 2 diabetes patients with hepatic steatosis, treatment with semaglutide resulted in a significant improvement in fatty liver resolution compared to placebo.

Using Artificial Intelligence to Semi-Quantitate Coronary Calcium as an ‘Incidentaloma’ on Non-Gated, Non-Contrast CT Scans, A Single-Center Descriptive Study in West Michigan.

INTRODUCTION Non-gated, non-contrast computed tomography (CT) scans are commonly ordered for a variety of non-cardiac indications, but do not routinely comment on the presence of coronary artery calcium (CAC)/atherosclerotic cardiovascular disease (ASCVD) which is known to correlate with increased cardiovascular risk. Artificial intelligence (AI) algorithms can help detect and quantify CAC/ASCVD which can lead to early treatment and improved outcomes. METHODS Using an FDA-approved algorithm (NANOX AI) to measure coronary artery calcium (CAC) on non-gated, non-contrast CT chest, 536 serial scans were evaluated in this single-center retrospective study. Scans were categorized by Agatston scores as normal-mild (<100), moderate (100-399), or severe (≥400). AI results were validated by cardiologist’s overread. Patient charts were retrospectively analyzed for clinical characteristics. RESULTS Of the 527 patients included in this analysis, a total of 258 (48.96%) had moderate-severe disease; of these, 164 patients (63.57%, p< 0.001) had no previous diagnosis of CAD. Of those with moderate-severe disease 135 of 258 (52.33% p=0.006) were not on aspirin and 96 (37.21% p=0.093) were not on statin therapy. Cardiologist interpretation demonstrated 88.76% agreement with AI classification. DISCUSSION/CONCLUSION Machine learning utilized in CT scans obtained for non-cardiac indications can detect and semi-quantitate CAC accurately. Artificial intelligence algorithms can accurately be applied to non-gated, non-contrast CT scans to identify CAC/ASCVD allowing for early medical intervention and improved clinical outcomes.

Survei Penentuan Tingkat Panduan Diagnostik pada CT Scan Kepala dan Abdomen Non-Kontras di Rumah Sakit

Diagnostic reference level (DRL) is still low for monitoring patient doses on hospital CT Scan. The need for radiation monitoring of CT Scan patients is related to radiation protection. CT Scan have a large dose, and as CT Scan develop, it is necessary to monitor the dose of CT Scan, especially those related to DRL. The importance of DRL is related to efforts to optimize radiation protection, which must be monitored regularly so that patients receive the lowest possible dose with optimal image quality. Determination of the local DRL value from quartile 2 (Q2) and national DRL with Quartile 3 (Q3) from the average CTDI vol and total DLP recordings of non-contrast CT Scan of the head and abdomen. From the survey results, local DRL calculations and national DRL contribution or I-DRL are as follows: CT scan of the head based on Q2 and Q3 obtained CTDIvol of 63.45 mGy. Meanwhile, based on Q2, it is 913,68 mGy.cm; in Q3, the DLP is 1096,42 mGy.cm; this value is below the national standard. The CT Scan Abdomen CTDIvol examination based on Q2 obtained 8.08 mGy. and based on Q3 of 10.18 mGy. Both are below the national average of 17 mGy. DLP results based on Q2 got a result of 321.99 mGy.cm, and based on Q3 obtained a result of 419,82 mGy.cm; both values are below the standard. National standards are based on the Head of BAPETEN Decree 1211/K/V/2021. DRL that exceeds the national standard for head CT Scan requires a protocol review to obtain the lowest possible dose, but the image quality remains optimal. It is an effort to optimize radiation protection. Keywords: Diagnostic Reference Level, CT Scan, Head, Abdomen, Non-Contrast

Diagnostic performance and feasibility of dual-layer detector dual-energy CT for characterization of urinary stones in patients of different sizes.

Urinary stones are frequently encountered in urology and are typically identified using non-contrast CT scans. Dual-energy CT (DECT) is a valuable imaging technique that produces material-specific images and allows for precise assessment of stone composition by estimating the effective atomic number (Zeff), a capability not achievable with the conventional single-energy CT's attenuation measurement method. To investigate the diagnostic performance and image quality of dual-layer detector DECT (dlDECT) in characterizing urinary stones in patients of different sizes. All consecutive dlDECT examinations with stone protocol and presence of urinary stones between July 2018 and November 2019 were retrospectively evaluated. Two radiologists independently reviewed 120 kVp and color-overlay Zeff images to determine stone composition (reference standard = crystallography) and image quality. The objective analysis included image noise and Zeff values measurement. A total of 739 urinary stones (median size 3.7 mm, range 1-35 mm) were identified on 177 CT examinations from 155 adults (mean age, 57 ± 15 years, 80 men, median weight 82.6 kg, range 42.6-186.9 kg). Using color-overlay Zeff images, the radiologists could subjectively interpret the composition in all stones ≥ 3 mm (n = 491). For stones with available reference standards (n = 74), dlDECT yielded a sensitivity of 80% (95%CI 44-98%) and a specificity of 98% (95%CI 92-100%) in visually discriminating uric acid from non-uric acid stones. Patients weighing > 90 kg and ≤ 90 kg had similar stone characterizability (p = 0.20), with 86% of stones characterized in the > 90 kg group and 87% in the ≤ 90 kg group. All examinations throughout various patients' weights revealed acceptable image quality. A Zeff cutoff of 7.66 accurately distinguished uric acid from non-uric acid stones (AUC = 1.00). Zeff analysis revealed AUCs of 0.78 and 0.91 for differentiating calcium-based stones from other non-uric stones and all stone types, respectively. dlDECT allowed accurate differentiation of uric acid and non-uric acid stones among patients with different body sizes with acceptable image quality. The ability to accurately differentiate uric acid stones from non-uric acid stones using color-overlay Zeff images allows for better tailored treatment strategies, helping to choose appropriate interventions and prevent potential complications related to urinary stones in patient care.

To report hounsfeld units or not: There is no question

IntroductionMost adrenal incidentalomas are not appropriately evaluated. Reporting the mass in the radiology report summary and providing recommendations in the report can positively impact evaluation. This study evaluated the effect of reporting Hounsfield units(HU) on adrenal incidentaloma follow-up. MethodsPatients with adrenal incidentalomas identified on noncontrast CT scan from 2015 to 2020 ​at a tertiary care institution were studied. Chart review was conducted. Patient and imaging characteristics were compared between patients who did and did not have HU reported. Outcomes of interest were 1)outpatient referral, 2)biochemical evaluation, and 3)dedicated imaging if appropriate. Multivariate analysis determined the impact of HU, reporting in the summary and provision of recommendations on the outcomes. Results363 patients were studied, 36(9.9 ​%) had HU reported. When HU were used in addition to recommendations and reporting in the summary, the likelihood of outpatient referral increased from 10.1 to 32.6-fold (95%CI 7.7–138.1, p ​< ​0.001). Similarly, the likelihood of biochemical workup increased from 2.5 to 7.8-fold (95%CI 2.5–24.1, p ​< ​0.001). ConclusionRecording adrenal incidentaloma HU on non-contrast CT scans was associated with increased rates of outpatient referral and biochemical workup.

Diagnostic Accuracy and Performance Analysis of a Scanner-Integrated Artificial Intelligence Model for the Detection of Intracranial Hemorrhages in a Traumatology Emergency Department.

Intracranial hemorrhages require an immediate diagnosis to optimize patient management and outcomes, and CT is the modality of choice in the emergency setting. We aimed to evaluate the performance of the first scanner-integrated artificial intelligence algorithm to detect brain hemorrhages in a routine clinical setting. This retrospective study includes 435 consecutive non-contrast head CT scans. Automatic brain hemorrhage detection was calculated as a separate reconstruction job in all cases. The radiological report (RR) was always conducted by a radiology resident and finalized by a senior radiologist. Additionally, a team of two radiologists reviewed the datasets retrospectively, taking additional information like the clinical record, course, and final diagnosis into account. This consensus reading served as a reference. Statistics were carried out for diagnostic accuracy. Brain hemorrhage detection was executed successfully in 432/435 (99%) of patient cases. The AI algorithm and reference standard were consistent in 392 (90.7%) cases. One false-negative case was identified within the 52 positive cases. However, 39 positive detections turned out to be false positives. The diagnostic performance was calculated as a sensitivity of 98.1%, specificity of 89.7%, positive predictive value of 56.7%, and negative predictive value (NPV) of 99.7%. The execution of scanner-integrated AI detection of brain hemorrhages is feasible and robust. The diagnostic accuracy has a high specificity and a very high negative predictive value and sensitivity. However, many false-positive findings resulted in a relatively moderate positive predictive value.

Artificial Intelligence–Aided Selection of Needle Pathways: Proof-of-Concept in Percutaneous Lung Biopsies

PurposeTo evaluate the concordance between lung biopsy puncture pathways determined by artificial intelligence (AI) and those determined by expert physicians. Materials and MethodsAn AI algorithm was created to choose optimal lung biopsy pathways based on segmented thoracic anatomy and emphysema in volumetric lung computed tomography (CT) scans combined with rules derived from the medical literature. The algorithm was validated using pathways generated from CT scans of randomly selected patients (n = 48) who had received percutaneous lung biopsies and had noncontrast CT scans of 1.25-mm thickness available in picture archiving and communication system (PACS) (n = 28, mean age, 68.4 years ± 9.2; 12 women, 16 men). The algorithm generated 5 potential pathways per scan, including the computer-selected best pathway and 4 random pathways (n = 140). Four experienced physicians rated each pathway on a 1–5 scale, where scores of 1–3 were considered safe and 4–5 were considered unsafe. Concordance between computer and physician ratings was assessed using Cohen’s κ. ResultsThe algorithm ratings were statistically equivalent to the physician ratings (safe vs unsafe: κ¯=0.73; ordinal scale: κ¯=0.62). The computer and physician ratings were identical in 57.9% (81/140) of cases and differed by a median of 0 points. All least-cost “best” pathways generated by the algorithm were considered safe by both computer and physicians (28/28) and were judged by physicians to be ideal or near ideal. ConclusionsAI-generated lung biopsy puncture paths were concordant with expert physician reviewers and considered safe. A prospective comparison between computer- and physician-selected puncture paths appears indicated in addition to expansion to other anatomic locations and procedures.

Coronary and Extra-coronary Subclinical Atherosclerosis to Guide Lipid-Lowering Therapy.

To discuss and review the technical considerations, fundamentals, and guideline-based indications for coronary artery calcium scoring, and the use of other non-invasive imaging modalities, such as extra-coronary calcification in cardiovascular risk prediction. The most robust evidence for the use of CAC scoring is in select individuals, 40-75 years of age, at borderline to intermediate 10-year ASCVD risk. Recent US recommendations support the use of CAC scoring in varying clinical scenarios. First, in adults with very high CAC scores (CAC ≥ 1000), the use of high-intensity statin therapy and, if necessary, guideline-based add-on LDL-C lowering therapies (ezetimibe, PCSK9-inhibitors) to achieve a ≥ 50% reduction in LDL-C and optimally an LDL-C < 70 mg/dL is recommended. In patients with a CAC score ≥ 100 at low risk of bleeding, the benefits of aspirin use may outweigh the risk of bleeding. Other applications of CAC scoring include risk estimation on non-contrast CT scans of the chest, risk prediction in younger patients (< 40 years of age), its value as a gatekeeper for the decision to perform nuclear stress testing, and to aid in risk stratification in patients presenting with low-risk chest pain. There is a correlation between extra-coronary calcification (e.g., breast arterial calcification, aortic calcification, and aortic valve calcification) and incident ASCVD events. However, its role in informing lipid management remains unclear. Identification of coronary calcium in selected patients is the single best non-invasive imaging modality to identify future ASCVD risk and inform lipid-lowering therapy decision-making.

Hematuria: Is it useful in predicting renal or ureteral stones in patient presenting to emergency department with flank pain?

The objective of the study was to evaluate hematuria as a diagnostic test for renal and ureteral stones compared with a noncontrast-enhanced computed tomography (CT) scan (gold standard test) in emergency room patients with acute flank pain. In total, 604 patients treated in our emergency department from 2006 to 2011, with a history of flank pain and suspected urolithiasis were included in a retrospective review. All patients were evaluated with a noncontrast-enhanced CT scan and urine analysis. Using the noncontrast CT scan as the gold standard for the evaluation of the presence, number, size, and site (renal or ureteral [upper, middle, and lower]) of the stones, we calculated the sensitivity, specificity, and positive and negative predictive values of hematuria for diagnosing both renal and ureteral stones. Urolithiasis was diagnosed in 388 patients (64%) and 216 patients (36%) had no stones on a noncontrast-enhanced CT scan. The sensitivity, specificity, positive predictive value, and negative predictive value for microhematuria were 77%, 33%, 67%, and 45%, respectively. Microhematuria was more common in patients with ureteral stones only (139 patients) and had a sensitivity of 85% compared to patients with renal stones only (32 patients), with a sensitivity of 55% (P < 0.001). There were no significant differences in the specificity or positive or negative predictive values. Although microhematuria is more sensitive to ureteral stones, the absence of microhematuria does not exclude the possibility of urolithiasis and a noncontrast-enhanced CT scan should be the gold standard diagnostic tool.

Performance of ensemble of UNets for epicardial adipose tissue quantification: a multi-center APOLLO study

Abstract Background Epicardial adipose tissue (EAT) surrounding the heart and coronary arteries, has been proposed to be a potential therapeutic target for the prevention of cardiac remodeling and arrhythmias in cardiovascular disease. Specifically, EAT volume is positively correlated with these cardiovascular events and therapeutic options are being developed with the aim to reduce EAT volume. EAT volume can be measured from non-contrast CT scans, but requires manual segmentation of the pericardium to isolate the EAT, which is prone to inter-observer variability. Purpose We aimed to develop a new AI EAT toolkit for automated quantification of EAT volume from multi-center non-contrast CT data and assess its performance against clinical annotations from four trained human experts. Methods This is a multicenter study which performs CT scans in 5000 Asian Admixture patients (APOLLO study). In the current stage of this study, NCCT data analysis was conducted in 1003 patients (mean age of 58±11 years; 33% females, with ethnicity breakdown of 72% Chinese, 20% Indian/Malay, 8% Others). Of these patients, 52% had hypertension, 19% had diabetes, 69% had hyperlipidemia, and 31% had obesity. AI EAT tool was developed via a novel deep learning framework using an ensemble of UNets (See Figure 1 and 2). The performance of AI EAT tool was evaluated with respect to expert clinical segmentations of four independent raters for a test dataset of 50 patient scans using dice similarity coefficient (DSC), Pearson correlation, and Bland-Altman analysis. Results The AI EAT quantification process took less than 20 seconds per subject, compared with 20-30 minutes for expert readers. Compared to clinical ground truth, our AI EAT achieved a DSC of 96.0 ± 1.0% and 89.1 ± 3.0% for pericardium and EAT segmentations, respectively. There was strong agreement between the AI EAT and clinical ground truth in deriving the EAT volume (r=0.99, p&amp;lt;0.001) and minimal error of 5.3±2.6%. The Bland-Altman analysis revealed the mean bias between the predicted EAT volume and the ground truth volumes to be 0.95 cm³ with the limits of agreement as [-12.86 cm³, 14.77 cm³]. Conclusion Ensemble of UNets based AI EAT tool is a novel method with high performance for the quantification of epicardial adipose tissue volume, as a potential diagnostic and prognostic tool for cardiac remodeling and arrhythmias.Figure 1.Ensemble of UNets framework.Figure 2.UNet Architecture used.

Abstract 18984: Artificial Intelligence-Based Automated Left Ventricle Mass Quantification From Non-Contrast Cardiac CT Scans: Correlation With Contrast CT and Cardiac MRI

Background: Non-contrast CT scans are currently not used to assess left ventricular myocardial mass (LV mass), which is usually evaluated with contrast CT or cardiac magnetic resonance (CMR). We aimed to assess the feasibility of LV mass estimation from non-contrast CT calcium scans using an artificial intelligence (AI) approach and compare it to measurements from contrast CT and CMR. Methods: A total of 316 patients (Age: 57.1±16.7, 53.2% male) who underwent coronary CT angiography (with non-contrast calcium CT and contrast CT) and CMR were included. The median interval between CT and CMR was 22 days (IQR: 3-76). An nn-Unet AI model (Total Segmentator), previously trained on data from independent sites, automatically segmented non-contrast CT structures including the myocardium. LV mass was also measured from contrast CT and CMR by experts during routine clinical reporting. Results: The AI segmentation took ~22 seconds per case. There was no significant difference in LV mass between the AI and contrast CT (136.5±55.3 vs. 139.6±58.0 g, p=0.114). An excellent correlation was observed between AI and contrast CT (r=0.84, p&lt;0.001) (Figure). Bland-Altman analysis showed a minimal bias of 3.15. Compared to CMR, both AI and non-contrast CT showed higher LV mass (136±55.3, 139.6±58.0 vs. 127.1±53.1 g, respectively, both p&lt;0.001). The correlations of AI and contrast CT with CMR were excellent with no significant differences. (r= 0.86 and 0.85, both p&lt;0.001). Bland-Altman analysis indicated small bias toward higher LV mass with AI and contrast CT (-9.35 and -12.5, respectively) compared to CMR. Conclusions: The AI-based automated LV mass from non-contrast CT showed excellent correlations and minimal biases when compared to LV mass measured from contrast CT and CMR. This fully automated measure could be applied for routine LV mass evaluation in patients with a non-contrast CT scan, providing an additional biomarker previously thought not measurable by this modality.

Abstract 360: Clinical Characteristics and Outcome in Out-of-Cardiac Arrest Patients With Type A Aortic Dissection Diagnosed by Non-Contrast Computed Tomography

Background: Although type A aortic dissection (AAD) remains a life-threatening disease, the exact epidemiology of out-of-hospital cardiac arrest (OHCA) with AAD is unclear. It has been reported that the non-contrast computed tomography (CT) is useful for diagnosing AAD in patients whose hemodynamic status was unstable. Aim: We evaluated the clinical features and outcome of OHCA patients with AAD diagnosed by non-contrast CT. Methods: Between 2017 and 2022, we retrospectively collected Utstein-style data on non-traumatic adult OHCA patients transferred to our hospital and performed non-contrast full-body CT scan. We divided OHCA patients into 3 groups: patients with AAD diagnosed by CT (Group-AAD), patients with non-cardiac cause without AAD (Group-NC), and patients with cardiac cause (Group-C). The diagnostic criteria of AAD by CT were as follows: visible intimal flap; crescentic high attenuation hematoma; and inward shift of calcified intima. The clinical outcome was defined as return of spontaneous circulation (ROSC). Results: Of the 1018 non-traumatic adult OHCA patients were registered during the study period, 1015 patients underwent non-contrast CT (Group-AAD, n=79; Group-NC, n=159; Group-C, n=779). The patients who achieved return of spontaneous circulation (ROSC) was 271 (26.8%). The proportion of patients who achieved ROSC in Group-AAD was significantly smaller than the other groups (Group-AAD 10.1%, Group-NC 27.7%, Group-C 28.3%, P=0.002). Multivariable logistic regression analysis revealed that patients with AAD diagnosed by CT independently predicted failure to achieve ROSC. The presence of witnessed arrest and initial shockable rhythm were significant indenpent predictors of achieving ROSC ( Table ). Conclusion: OHCA patients with AAD diagnosed with CT were more difficult to obtain ROSC than patients with other cause.