Abdominopelvic Computed Tomography Research Articles

Systemic lupus erythematosus in a 15-year-old female with multiple splenic nodules: A case report

BACKGROUND Systemic lupus erythematosus (SLE) is a chronic inflammatory disease primarily affecting young females. SLE can invade any organ, and various forms of splenic invasion have been reported. Manifestations include splenomegaly and splenic infarction, rupture, and calcification. The study encountered a rare case of splenic involvement, with nodules of various sizes without calcifications or ruptures. CASE SUMMARY A 15-year-old girl presented with arthralgia, weight loss, fever, increased levels of inflammatory markers, and positive antinuclear antibody test results. The patient was diagnosed with SLE. She was asymptomatic while taking steroids and hydroxychloroquine. Ten months after discharge, the patient developed a fever and abdominal pain. Lupus enteritis was suspected, and abdominopelvic computed tomography (AP-CT) was performed. There were no specific findings in the gastrointestinal tract, but multiple splenic nodules were observed. Infection or hemangioma was considered; however, no specific radiological findings were observed. A biopsy of the spleen was performed to determine the possibility of malignancy. The histological findings of the spleen included extensive periarteriolar necrosis with hematoxylin bodies and numerous karyorrhectic debris. Based on the biopsy results, the patient was diagnosed with an SLE flare-up and was maintained on high-dose steroids and immunosuppressants. CONCLUSION As disease activity increased, multiple nodules in the spleen that were previously unseen were observed using AP-CT and histologically confirmed. Spleen invasion by SLE can appear in multiple nodular forms and patterns. Therefore, physicians should consider these findings when differentiating these nodules from infections and malignancies.

Utility of Combined Use of Imaging Features From Abdominopelvic CT and CA 125 to Identify Presence of CT Occult Peritoneal Metastases in Advanced Gastric Cancer.

The purpose of this study is to identify the presence of occult peritoneal metastasis (OPM) in patients with advanced gastric cancer (AGC) by using clinical characteristics and abdominopelvic computed tomography (CT) features. This retrospective study included 66 patients with OPM and 111 patients without peritoneal metastasis (non-PM [NPM]) who underwent preoperative contrast-enhanced CT between January 2020 and December 2021. Occult PMs means PMs that are missed by CT but later diagnosed by laparoscopy or laparotomy. Patients with NPM means patients have neither PM nor other distant metastases, indicating there is no evidence of distant metastases in patients with AGC. Patients' clinical characteristics and CT features such as tumor marker, Borrmann IV, enhancement patterns, and pelvic ascites were observed by 2 experienced radiologists. Computed tomography features and clinical characteristics were combined to construct an indicator for identifying the presence of OPM in patients with AGC based on a logistic regression model. Receiver operating characteristic curves and the area under the receiver operating characteristic curve (AUC) were generated to assess the diagnostic performance of the combined indicator. Four independent predictors (Borrmann IV, pelvic ascites, carbohydrate antigen 125, and normalized arterial CT value) differed significantly between OPM and NPM and performed outstandingly in distinguishing patients with OPM from those without PM (AUC = 0.643-0.696). The combined indicator showed a higher AUC value than the independent risk factors (0.820 vs 0.643-0.696). The combined indicator based on abdominopelvic CT features and carbohydrate antigen 125 may assist clinicians in identifying the presence of CT OPMs in patients with AGC.

O85: Discrepancy Rates in Acute Abdominal CT: A Comparison of In-House and Remote Reporting to Intra-Operative Laparoscopic and Laparotomy Findings

Abstract Non-traumatic abdominal pain is a common emergency presentation frequently managed by General Surgeons. Abdominopelvic computed tomography (CT) scans are the most popular imaging modality in this context. In many hospitals, the rising demand for urgent and emergent scans out-of-hours has necessitated the outsourcing of this service to teleradiology companies whereby reports are generated at sites remote from the image acquisition. The primary aim of this study was to determine the discrepancy rates of pre-operative CT imaging by source (Teleradiology compared to in-house). This was a retrospective monocentric study conducted at a busy district general hospital over a seven-month period. Patient demographic data, operative notes, and radiology reports (by source) were collated for all patients aged ≥ 16 years presenting with atraumatic abdominal pain who underwent abdominopelvic CT with subsequent surgical intervention (laparoscopy and/or laparotomy). 71 patients were identified by initial screening, 10 patients (11 scans) met the criteria for a ‘major’ discrepancy. Overall discrepancy rates were calculated at 5.6% for scans reported off-site compared to 9.9% for reports generated by in-house radiologists, P = 0.192 (p < 0.05), OR 2.625 (95% CI 0.6915 to 8.595). This study demonstrated lower discrepancy rates in scans reported remotely and can be used as the catalyst for improving aspects of in-house CT reporting.

Institutional clinical indication-based typical dose values of multiphasic abdominopelvic computed tomography examinations.

Our study aimed to obtain clinical indication-based typical dose values and size-specific dose estimates (SSDEs) for multiphasic abdominopelvic computed tomography (CT) examinations and to review our data with published diagnostic reference levels (DRLs). In this retrospective study, multiphasic liver, kidney, pancreas, and mesenteric ischemia protocol CT scans performed at our center between January 2018 and December 2021 were analyzed. The clinical indications were hepatocellular carcinoma, renal cell carcinoma, pancreas adenocarcinoma, and mesenteric ischemia. The computed tomography dose index volume (CTDIvol) and dose-length product (DLP) values were recorded, and the SSDE and effective dose (ED) values were calculated. The water-equivalent diameter (Dw) value required for the SSDE calculation was measured using the automated calculation of the Dw program. The total number of patients was 514, with 86 patients excluded from this study. The dose values were calculated for 426 patients (183 female and 243 male; 111 liver, 120 kidney, 85 pancreas, and 110 mesenteric). The median values for the CTDIvol, DLP, SSDE, and ED were 6.86 mGy, 683.02 mGy. cm, 8.75 mGy, and 10.45 mSv for the liver CT; 8.37 mGy, 908.37 mGy.cm, 10.37 mGy, and 13.89 mSv for the kidney CT; 7.82 mGy, 517.98 mGy.cm, 10.01 mGy, and 7.92 mSv for the pancreas CT; and 9.48 mGy, 983.68 mGy.cm, 12.78 mGy, and 13.86 mSv for the mesenteric CT, respectively. All dose values were lower than the published DRLs. The literature reveals large differences in the multiphasic abdominopelvic CT protocols, especially in the number of phases and scan length. This situation makes comparing dose values difficult. Dose studies revealing the protocol parameters in detail are needed so that institutions can compare and optimize their own protocols. Additionally, users should periodically check the dose values in their own institutions.

Expanding Access to Computed Tomographic Staging and Three-Dimensional Intensity Modulated Radiotherapy for Cervical Cancer in Ghana.

To build capacity for improved treatment of locally advanced cervical cancer in Ghana, including computed tomography (CT) staging and intensity modulated radiotherapy (IMRT). Patients with histologically confirmed cervical cancer were prospectively staged with abdominopelvic CT and ultrasound and offered the opportunity to have IMRT instead of conventional two-dimensional radiotherapy. The development of an efficient, high-quality, and safe IMRT program was facilitated by investment in new technology and comprehensive training of the interdisciplinary radiotherapy team in collaboration with a North American center of excellence. Of 215 patients with cervical cancer referred in 2022, 66% were able to afford CT scans and 26% were able to afford IMRT. Lymph node metastases were identified in 52% of patients by CT but in only 2% of patients by ultrasound. The use of CT resulted in 63% of patients being upstaged and changed treatment intent or radiation treatment volumes in 67% of patients. Patients who had IMRT experienced fewer acute side effects and were more likely to complete treatment as planned. It is feasible to provide state-of the-art cancer treatment with CT staging and IMRT to patients with cervical cancer in low-resource settings and achieve meaningful improvements in outcomes. It requires a broad commitment by program leadership to invest in technology and staff training. Major challenges include balancing improved clinical care with reduced patient throughput when radiation treatment capacity is constrained, and with the additional cost in the absence of universal health coverage.

Immunoglobulin-G4 Related Disease with Multiple Organ Involvement

Dear Editor, Immunoglobulin G4-related disease (IgG4-RD) is an immune-mediated fibroinflammatory disease affecting multiple organ systems. The clinical findings may range due to the affected organ. The main distinguishing histopathological features of IgG4-RD are lymphoplasmacytic infiltration, storiform fibrosis, obliterative phlebitis, and mild or moderate tissue eosinophilia. Rarely, it may affect the lungs, hearts, pituitary, meninges, skin, prostate, breast, and thyroid gland [1–3]. In this article, we present a case diagnosed with IgG4-related disease involving multiple organs, including the pituitary, lymphatic system, kidney, and heart, and the patient responded well to immunosuppressive treatment. A fifty-five-year-old female patient applied with complaints of fatigue, polydipsia, polyuria, widespread body pain, and 20 kg weight loss in the last year. After excluding other possibilities, with a prediagnosis of diabetes insipidus (DI) pituitary MRI was performed which showed an increase in size and heterogeneous patchy contrast enhancement in the adenohypophysis (Fig. 1a). Based on the current clinical and imaging findings, the patient's laboratory results were evaluated, and central DI was diagnosed. In computerized thorax tomography, multiple lymph nodes in the mediastinum were detected, the largest of which was 21x17 mm. Tissue sampling was performed with the guidance of EBUS, pathological examination showed no diagnostic findings. Transesophageal Echocardiography (TEE) revealed an appearance consistent with a 10-15 mm thick thrombus surrounding the left atrium wall and narrowing the cavity. Increased thickness narrowing the left atrial lumen was reported in thorax computed tomography (CT) (Fig. 2). Further, a cardiac MRI was performed and reported to be consistent with lymphoproliferative-inflammatory involvement rather than thrombus. Abdominopelvic CT was performed and a lesion of 54x28 mm in size, less contrast enhancing than the surrounding parenchyma, in the middle part posterior of the left kidney was detected (Fig. 3). Histopathological findings were consistent with inflammatory processes, and no findings in favor of a neoplastic lymphoproliferative process were detected in the samples. Since the patient was presented with pituitary involvement, mediastinal lymphadenopathy, renal and cardiac mass, the IgG4 level was ordered and resulted as 299 mg/dl (3-201). IgG4 staining could not be performed in the current biopsy specimen; for confirming the diagnosis of IgG4-related disease, a re-biopsy was performed on the kidney mass. Histopathological findings were consistent with IGG4-RD (Fig. 4). Due to multisystemic involvement, the patient received 0.6 mg/kg/day oral corticosteroid and mycophenolate mofetil 3x1000 mg/day. The pituitary MRI that was performed in the first month of treatment was normal (Fig. 1b). Desmopressin treatment was stopped. Also, control TEE in the first-month follow-up visit showed a significant reduction in the mass image in the left atrium. After three months of follow-up, there was a significant improvement in the patient's symptoms and acute phase response. The corticosteroid was tapered and maintenance treatment with mycophenolate mofetil was continued. IgG4-related disease is rare and difficult to diagnose, though its presentation may be in a wide variety of clinical features. It is crucial to make an early diagnosis and start treatment early in these patients to prevent morbidity and mortality. In cases with mass lesions and especially with multiple organ involvement, as in our case, IgG4-related disease should be kept in mind, and IgG4 staining should always be kept in mind. Kind Regards

Opportunistic assessment of ischemic heart disease risk using abdominopelvic computed tomography and medical record data: a multimodal explainable artificial intelligence approach

Current risk scores using clinical risk factors for predicting ischemic heart disease (IHD) events—the leading cause of global mortality—have known limitations and may be improved by imaging biomarkers. While body composition (BC) imaging biomarkers derived from abdominopelvic computed tomography (CT) correlate with IHD risk, they are impractical to measure manually. Here, in a retrospective cohort of 8139 contrast-enhanced abdominopelvic CT examinations undergoing up to 5 years of follow-up, we developed multimodal opportunistic risk assessment models for IHD by automatically extracting BC features from abdominal CT images and integrating these with features from each patient’s electronic medical record (EMR). Our predictive methods match and, in some cases, outperform clinical risk scores currently used in IHD risk assessment. We provide clinical interpretability of our model using a new method of determining tissue-level contributions from CT along with weightings of EMR features contributing to IHD risk. We conclude that such a multimodal approach, which automatically integrates BC biomarkers and EMR data, can enhance IHD risk assessment and aid primary prevention efforts for IHD. To further promote research, we release the Opportunistic L3 Ischemic heart disease (OL3I) dataset, the first public multimodal dataset for opportunistic CT prediction of IHD.

Evaluation of organ and effective doses using anthropomorphic phantom: A comparison between experimental measurement and a commercial dose calculator

IntroductionThe aim of this study was to experimentally measure organ doses for computed tomography (CT) procedures using thermoluminescence dosimeters (TLDs) on a RANDO anthropomorphic phantom and verify the measured doses using CT-Expo software. MethodsThe phantom was irradiated using clinical CT scan protocols routinely used for specific procedures in the radiology department. Fifty TLD chips were used in this study. The scanning parameters (kVp, mA, s) used to scan the phantom were used as input parameters for CT-Expo dose estimations. ResultsThe TLD measured organ doses varied between 3.97 mGy for the esophagus and 56.22 mGy for the brain. High doses were recorded in the brain (37.80–56.22 mGy) and the eye lens (29.94–36.16 mGy). Comparing the organ dose measurements between TLD and CT-Expo, the maximum organ dose difference was obtained for the eye lens. A comparison between the two methods for the other organs were all less than 32 %. The effective doses from the TLD measurements for the head, chest, and abdominopelvic CT examinations were 2.78, 6.67, and 17 mSv, respectively and CT-Expo were 2.20, 10.30, and 16.70 mSv, respectively. ConclusionThe experimental and computational results are comparable, and the reliability of the TLD measurements and CT-Expo dose calculator has been proven. Implications for studyA reason for the difference in dose measurements between the two methods has been attributed to the dissimilarity in the organ position in the Rando anthropomorphic phantom and the standard mathematical phantom used by CT-Expo. The experimental and computational results have been found to be comparable.

Reduced-dose CT in detecting solid liver tumors: A comparison of image quality between automatic exposure control and organ effective modulation

PurposeTo evaluate the subjective and objective image quality of solid liver tumors as well as the radiation dose using organ effective modulation (OEM) technology for abdominopelvic computed tomography (CT). Material and methodsA total of 74 patients who underwent contrast-enhanced abdominopelvic CT between January and April 2022 were prospectively enrolled in this study. Patients were randomly assigned to two groups: the non-OEM group underwent CT scans with automatic exposure control (AEC), while the OEM group underwent CT scans with OEM. The radiation dose was compared between the two groups. Objective image quality was quantitatively assessed using image noise, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR). Two experienced radiologists independently evaluated the CT images (5, best; 1, worst) by four characteristics including sharpness, contrast, noise, and diagnostic confidence. ResultsThe OEM group presented a significant reduction in volume CT dose index (CTDIvol), dose-length product (DLP), and effective dose (ED) by 11.4%, 12.2%, and 12.2%, respectively (p < 0.05). There were no significant differences between two groups concerning image noise, SNR, and CNR (p > 0.05). Expect for the left and right liver lobes in portal images, OEM was slightly higher than the non-OEM (p < 0.05). The subjective scores of two radiologists demonstrated good agreement (kappa value = 0.84). No statistically significant differences were observed in subjective grading (p > 0.05). ConclusionOEM technology can effectively reduce the radiation dose of abdominopelvic-enhanced CT without affecting the subjective and objective image quality of solid liver tumors.

When Not to Operate on Acute Cases-A Surgeon's Perspective on Rapid Assessment of Emergency Abdominopelvic Computed Tomography.

Clinical problem solving evolves in parallel with advances in technology and discoveries in the medical field. However, it always reverts to basic cognitive processes involved in critical thinking, such as hypothetical-deductive reasoning, pattern recognition, and compilation models. When dealing with cases of acute abdominal pain, clinicians should employ all available tools that allow them to rapidly refine their analysis for a definitive diagnosis. Therefore, we propose a standardized method for the quick assessment of abdominopelvic computed tomography as a supplement to the traditional clinical reasoning process. This narrative review explores the cognitive basis of errors in reading imaging. It explains the practical use of attenuation values, contrast phases, and windowing for non-radiologists and details a multistep protocol for finding radiological cues during CT reading and interpretation. This systematic approach describes the salient features and technical tools needed to ascertain the causality between clinical patterns and abdominopelvic changes visible on CT scans from a surgeon's perspective. It comprises 16 sections that should be read successively and that cover the entire abdominopelvic region. Each section details specific radiological signs and provides clear explanations for targeted searches, as well as anatomical and technical hints. Reliance on imaging in clinical problem solving does not make a decision dichotomous nor does it guarantee success in diagnostic endeavors. However, it contributes exact information for supporting the clinical assessments even in the most subtle and intricate conditions.

Have the UK Pediatric Trauma Protocols resulted in a reduction in chest computed tomography imaging for children presenting with major blunt trauma?

To observe variation in imaging requests after publication of the Royal College of Radiologists UK Paediatric Trauma Protocols in 2014, recommending limited use of thoracic computed tomography (CT) to appropriately clinically risk stratified children. A retrospective observational study using data from the Trauma Audit & Research Network in the United Kingdom, for children (0-16 years of age) for the years 2012-2021. Percentages were calculated to facilitate comparison between year groups (under 1 year of age, 1-10 years of age, 11-15 years of age), and CT imaging categories reviewed: (1) whole-body CT (WBCT); (2) abdominopelvic CT (CTAP) with chest radiograph (CXR); (3) chest, abdomen, and pelvic CT (CTCAP) with CXR; (4) CTCAP without CXR; and (5) other imaging. Increased use of the recommended protocol (CXR with CTAP) was observed after guidance publication but was not sustained: infants under 1 year old, 0.0% in 2012, 7% in 2017, 0.0% in 2021; 1-10-year-olds, 4% in 2012, 13.9% in 2017, 5.5% in 2021; 11-15-year-olds, 7.1% in 2012, 10.2% in 2017, 6.6% in 2021. Requests for WBCT increased from 2012-2021 (all age groups, 2.4%, 2012, to 5.3%, 2021) and requests for CTCAP were consistently at a higher level than that of the recommended protocol. The increased use of CXR with CTAP after publication of the guidelines, was not sustained with a decreasing trend observed from ∼2017, raising concern for the ionizing radiation burden in this population.

The role of computed tomography in enterolith causing small bowel obstruction: A case series.

Intestinal obstruction caused by enteroliths is an uncommon medical condition. Timely detection of the presence of enteroliths and identification of their origin can guide clinical treatment. This study aimed to present the Computed Tomography (CT) features of enterolithic ileus confirmed by surgery in 7 patients. Seven patients with surgically confirmed enterolithic ileus who were admitted to our hospital between December 2013 and December 2022 were continuously enrolled, and an abdominopelvic CT examination was performed before surgery. The imaging characteristics were then analyzed. In the transition zone of all patients with intestinal obstruction, the sharply defined intraluminal masses were found. Three of them had gallstones and 4 had primary enteroliths. All 5 enteroliths in the 4 patients with primary enteroliths were in the proximal small intestine and were low-density with gas. Additionally, 3 gallstones were present in the distal small bowel, and calcifications were observed. Simultaneously, cholecystitis and secondary cholecystoduodenal fistula were observed in all 3 patients with gallstones. Compared to gallstones, primary enteroliths tend to be higher positioned, less dense, and accompanied by gas. CT examination is very important, as it allows accurate identification, location, diagnosis, and identification of complications of the different types of enteroliths to provide a basis for surgery.

Optimal computed tomography-based biomarkers for prediction of incisional hernia formation.

Unstructured data are an untapped source for surgical prediction. Modern image analysis and machine learning (ML) can harness unstructured data in medical imaging. Incisional hernia (IH) is a pervasive surgical disease, well-suited for prediction using image analysis. Our objective was to identify optimal biomarkers (OBMs) from preoperative abdominopelvic computed tomography (CT) imaging which are most predictive of IH development. Two hundred and twelve rigorously matched colorectal surgery patients at our institution were included. Preoperative abdominopelvic CT scans were segmented to derive linear, volumetric, intensity-based, and textural features. These features were analyzed to find a small subset of OBMs, which are maximally predictive of IH. Three ML classifiers (Ensemble Boosting, Random Forest, SVM) trained on these OBMs were used for prediction of IH. Altogether, 279 features were extracted from each CT scan. The most predictive OBMs found were: (1) abdominopelvic visceral adipose tissue (VAT) volume, normalized for height; (2) abdominopelvic skeletal muscle tissue volume, normalized for height; and (3) pelvic VAT volume to pelvic outer aspect of body wall skeletal musculature (OAM) volume ratio. Among ML prediction models, Ensemble Boosting produced the best performance with an AUC of 0.85, accuracy of 0.83, sensitivity of 0.86, and specificity of 0.81. These OBMs suggest increased intra-abdominopelvic volume/pressure as the salient pathophysiologic driver and likely mechanism for IH formation. ML models using these OBMs are highly predictive for IH development. The next generation of surgical prediction will maximize the utility of unstructured data using advanced image analysis and ML.

Value of deep-learning image reconstruction at submillisievert CT for evaluation of the female pelvis

To assess the value of deep-learning reconstruction (DLR) at submillisievert computed tomography (CT) for the evaluation of the female pelvis, with standard dose (SD) hybrid iterative reconstruction (IR) images as reference. The present study enrolled 50 female patients consecutively who underwent contrast-enhanced abdominopelvic CT for clinically indicated reasons. Submillisievert pelvic images were acquired using a noise index of 15 for low-dose (LD) scans, which were reconstructed with DLR (body and body sharp), hybrid-IR, and model-based IR (MBIR). Additionally, SD scans were reconstructed with a noise index of 7.5 using hybrid-IR. Radiation dose, quantitative image quality, overall image quality, image appearance using a five-point Likert scale (1-5: worst to best), and lesion evaluation in both SD and LD images were analysed and compared. The submillisievert pelvic CT examinations showed a 61.09±4.13% reduction in the CT dose index volume compared to SD examinations. Among the LD images, DLR (body sharp) had the highest quantitative quality, followed by DLR (body), MBIR, and hybrid-IR. LD DLR (body) had overall image quality comparable to the reference (p=0.084) and favourable image appearance (p=0.209). In total, 40 pelvic lesions were detected in both SD and LD images. LD DLR (body and body sharp) exhibited similar diagnostic confidence (p=0.317 and 0.096) compared with SD hybrid-IR. DLR algorithms, providing comparable image quality and diagnostic confidence, are feasible in submillisievert abdominopelvic CT. The DLR (body) algorithm with favourable image appearance is recommended in clinical settings.

Unscarred uterine rupture with catastrophic hemorrhage immediately after vaginal delivery: diagnosis and management of six consecutive cases

Background To describe and explore the risk factors, clinical presentations, timely diagnostic approaches, and management in patients experiencing unscarred uterine rupture with catastrophic hemorrhage. Methods We retrospectively analyzed clinical and imaging data from women who encountered postpartum hemorrhage (PPH) and were diagnosed with unscarred uterine rupture within a three-year timeframe (2018-2020). The data were extracted from medical records obtained from a multi-hospital 24-hour emergency PPH transfer system. Results Six patients were identified as having unscarred uterine rupture after vaginal delivery. All six women were para 2, with four of them undergoing vacuum-assisted delivery. One patient experienced out-of-hospital cardiac arrest (OHCA), while five patients presented with hypovolemic shock. Abdominopelvic ultrasound revealed a boggy lower uterine segment. Initially, five patients underwent transarterial embolization (TAE) of the internal iliac arteries in an attempt to achieve hemostasis, but this approach proved unsuccessful. Abdominopelvic computed tomography (CT) confirmed the diagnosis of ruptured uterus by demonstrating disrupted myometrium and hemoperitoneum. Immediate exploratory laparotomy followed by life-saving hysterectomy was performed in all cases. The median estimated total blood loss was 2725 mL ± 900 mL (ranging from 1600 mL to 7100 mL). Lower segment lacerations were observed in all patients, with more extensive uterine damage noted in those who underwent vacuum extraction. The length of hospital stay varied between 9 and 38 days. Conclusion Instrument-assisted obstetric delivery is a possible contributing factor to unscarred uterine rupture in our study. In specific cases, the use of abdominopelvic CT prior to initiating transarterial embolization (TAE) offers valuable information to complement ultrasound findings. This comprehensive approach helps in accurately identifying the underlying cause of intractable postpartum hemorrhage (PPH). Immediate conversion to laparotomy is essential to explore the intra-abdominal factors causing PPH that cannot be controlled by TAE. The rational etiologies of uterine rupture must be clarified while generating practical guideline in the future.

Concordance of CT imaging and surgical lesions in penetrating abdominal trauma

The management of penetrating abdominal wounds has greatly benefited from the development of computed tomography (CT), particularly in stable patients. In this setting, the scanner is the reference examination. Our study aims to evaluate the performance of preoperative CT in the assessment of penetrating abdominal lesions. Between January 1, 2015 and January 1, 2022, 81 patients were hospitalized following penetrating abdominal trauma at the Army Training Hospitals of Sainte-Anne and Laveran. Fifty-one stable patients who had an abdominopelvic CT scan and thereafter underwent abdominal surgery (laparotomy or laparoscopy) were included. Radiological and surgical data were collected from the electronic record and compared by a descriptive analysis (calculation of the sensitivity, specificity, positive and negative predictive value of the CT for the detection of lesions of the various organs) and by a correlation of the CT findings with surgical findings using Kripendorff's alpha coefficient. The cohort was largely male (n=45; 88%), with injuries by knife wound in 62.7% of cases (n=32) and gunshot in 35.3% (n=18) of cases. The median age was 36years (25-47). The median index of severity score (ISS) was 17 (10-26). Excellent agreement between predicted and actual findings was obtained for solid organs (α=0.801) with high sensitivity and specificity (81.8% and 96.6%, respectively). The largest discrepancies were observed for the hollow organs (α=26.2%, sensitivity of 53.3% and specificity of 76.2%) and the diaphragm (α=67.3%, sensitivity 75%, specificity 92.3%). Surgical exploration was non-therapeutic for five patients (9.8%). The failure rate for non-operative treatment was 10% (n=1). CT detection of solid organ lesions in patients with penetrating abdominal wounds is excellent. However, the detection of hollow organ and diaphragmatic wounds remains a challenge with a risk of over- and underdiagnosis. Laparoscopic exploration should be able to fill in the gaps in the CT findings.

Association of CT-Derived Skeletal Muscle and Adipose Tissue Metrics with Frailty in Older Adults

Tools are needed for frailty screening of older adults. Opportunistic analysis of body composition could play a role. We aim to determine whether computed tomography (CT)-derived measurements of muscle and adipose tissue are associated with frailty. Outpatients aged ≥55 years consecutively imaged with contrast-enhanced abdominopelvic CT over a 3-month interval were included. Frailty was determined from the electronic health record using a previously validated electronic frailty index (eFI). CT images at the level of the L3 vertebra were automatically segmented to derive muscle metrics (skeletal muscle area [SMA], skeletal muscle density [SMD], intermuscular adipose tissue [IMAT]) and adipose tissue metrics (visceral adipose tissue [VAT], subcutaneous adipose tissue [SAT]). Distributions of demographic and CT-derived variables were compared between sexes. Sex-specific associations of muscle and adipose tissue metrics with eFI were characterized by linear regressions adjusted for age, race, ethnicity, duration between imaging and eFI measurements, and imaging parameters. The cohort comprised 886 patients (449 women, 437 men, mean age 67.9 years), of whom 382 (43%) met the criteria for pre-frailty (ie, 0.10< eFI ≤ 0.21) and 138 (16%) for frailty (eFI > 0.21). In men, 1 standard deviation changes in SMD (β = -0.01, 95% confidence interval [CI],-0.02 to-0.001, P=.02) and VAT area (β = 0.008, 95% CI,0.0005-0.02, P=.04), but not SMA, IMAT, or SAT, were associated with higher frailty. In women, none of the CT-derived muscle or adipose tissue metrics were associated with frailty. We observed a positive association between frailty and CT-derived biomarkers of myosteatosis and visceral adiposity in a sex-dependent manner.

Comparing the role of 99m Tc-HYNIC-PSMA-11 and 99m Tc-MDP scintigraphy for the initial staging of intermediate to high-risk prostate cancer.

Although bone scintigraphy and abdominopelvic computed tomography (CT)/MRI have been the mainstay of initial staging in the intermediate to high-risk prostate cancer (PC) patients, prostate-specific membrane antigen (PSMA) PET/CT imaging provides promising additional value in the initial N/M staging of these patients in recent years. 99m Tc-PSMA scan is a new alternative to PSMA PET tracers with little evidence regarding its diagnostic value in the initial staging of PC. This prospective study included 40 patients with newly diagnosed PC with initial intermediate or high-risk features [prostate-specific antigen (PSA) > 10 ng/dl, Gleason score ≥7 or stage cT2b and more]. All patients underwent both 99m Tc-methylene diphosphonate (MDP) bone scan and 99m Tc-HYNIC-PSMA-11 scan with maximum interval of 2 weeks. Abdominopelvic CT and MRI were also performed in this timeframe. Then, the results of these methods were compared with the final diagnosis data. Among the 40 included patients, 28 patients had finally been diagnosed as localized PC and 12 patients showed lymph node or metastatic involvement. The sensitivity, specificity and accuracy of 99m Tc-HYNIC-PSMA-11 vs. 99m Tc-MDP were 83.3% vs. 50.0%, 100% vs. 82.1% and 95% vs. 72.5%, respectively. However, when combined with the results of abdominopelvic CT/MRI the sensitivity reached 100% for both and the specificity raised to 100% and 96.4% for 99m Tc-HYNIC-PSMA-11 and 99m Tc-MDP, respectively. 99m Tc-HYNIC-PSMA-11 performs well in the initial staging of intermediate to high-risk PC and especially in low source areas without PET/CT it can be used as the first-line method of metastatic evaluation instead of bone scintigraphy. However, the combination and correlation of cross-sectional imaging is essential to gain the optimal diagnostic value.

Effect of High-Versus Low-Frequency of Abdominopelvic Computed Tomography Follow-Up Testing on Overall Survival in Patients With Stage II Or III Colon Cancer

BackgroundIntensive surveillance of colon cancer by using the abdominopelvic computed tomography (AP-CT) is common in real world practice; however, it is still unclear whether high-frequency surveillance using AP-CT in patients with these risk factors is superior to that in the low-frequency surveillance. Patients and MethodsWe retrospectively reviewed 1803 patients with stage II-III colon cancer receiving curative surgery between January 1, 2005 to December 31, 2015. We evaluated the average scan-to-scan intervals of postoperative AP-CT testing and assigned patients with an interval of 5 to 8 and 9 to 13 months to the high-frequency (HF) and low-frequency (LF) groups, respectively. The cutoff value of preoperative and postoperative CEA levels was 5 ng/mL. We also applied propensity score matching (PSM) and inverse probability of treatment weighting to adjust clinicopathologic differences between the 2 groups. ResultsWe matched 1:1 for each surveillance group yielding a cohort of 776 matched patients. After PSM, Baseline demographics were overall well balanced between 2 groups. Stage III (OR, 2.00; 95% Confidence interval [CI], 1.21-3.30) and postoperative CEA elevation (OR, 2.30; 95% CI, 1.08-4.92) were independent risk factors of recurrence in multivariate analyses. Patient in the HF group had more surgery plus chemo- or radiotherapy as postrecurrence treatment than patient in the LF group (46.2% vs. 23.1%, P = .017). This trend was retained after PSM, although it is not significant (44.4% vs. 23.1%, P = .060). However, survival outcomes of high-frequency AP-CT surveillance were not superior to those of low-frequency surveillance in all subgroups, including stage III (HR 0.99, 95% CI 0.40-2.47) and postoperative CEA elevation (HR 1.36, 95% CI 0.45-4.11). ConclusionHigh-frequency AP-CT testing is associated with a higher proportion of surgery plus chemo- or radiotherapy as postrecurrence treatment, without improvement in 5-year overall survival.

Diagnostic Accuracy of Unenhanced Computed Tomography for Evaluation of Acute Abdominal Pain in the Emergency Department

Intravenous (IV) contrast medium is sometimes withheld due to risk of complication or lack of availability in patients undergoing computed tomography (CT) for abdominal pain. The risk from withholding contrast medium is understudied. To determine the diagnostic accuracy of unenhanced abdominopelvic CT using contemporaneous contrast-enhanced CT as the reference standard in emergency department (ED) patients with acute abdominal pain. This was an institutional review board-approved, multicenter retrospective diagnostic accuracy study of 201 consecutive adult ED patients who underwent dual-energy contrast-enhanced CT for the evaluation of acute abdominal pain from April 1, 2017, through April 22, 2017. Three blinded radiologists interpreted these scans to establish the reference standard by majority rule. IV and oral contrast media were then digitally subtracted using dual-energy techniques. Six different blinded radiologists from 3 institutions (3 specialist faculty and 3 residents) interpreted the resulting unenhanced CT examinations. Participants included a consecutive sample of ED patients with abdominal pain who underwent dual-energy CT. Contrast-enhanced and virtual unenhanced CT derived from dual-energy CT. Diagnostic accuracy of unenhanced CT for primary (ie, principal cause[s] of pain) and actionable secondary (ie, incidental findings requiring management) diagnoses. The Gwet interrater agreement coefficient was calculated. There were 201 included patients (female, 108; male, 93) with a mean age of 50.1 (SD, 20.9) years and mean BMI of 25.5 (SD, 5.4). Overall accuracy of unenhanced CT was 70% (faculty, 68% to 74%; residents, 69% to 70%). Faculty had higher accuracy than residents for primary diagnoses (82% vs 76%; adjusted odds ratio [OR], 1.83; 95% CI, 1.26-2.67; P = .002) but lower accuracy for actionable secondary diagnoses (87% vs 90%; OR, 0.57; 95% CI, 0.35-0.93; P < .001). This was because faculty made fewer false-negative primary diagnoses (38% vs 62%; OR, 0.23; 95% CI, 0.13-0.41; P < .001) but more false-positive actionable secondary diagnoses (63% vs 37%; OR, 2.11, 95% CI, 1.26-3.54; P = .01). False-negative (19%) and false-positive (14%) results were common. Interrater agreement for overall accuracy was moderate (Gwet agreement coefficient, 0.58). Unenhanced CT was approximately 30% less accurate than contrast-enhanced CT for evaluating abdominal pain in the ED. This should be balanced with the risk of administering contrast material to patients with risk factors for kidney injury or hypersensitivity reaction.