Probabilistic Prediction of Gastrointestinal Ischemia after Cardiothoracic Surgery.

BACKGROUND: Gastrointestinal ischemia (GIisch) is challenging to diagnose in patients after cardiothoracic surgery. Computed tomography angiography (CTA) carries substantial false-negative and false-positive rates. The aim of the study was to evaluate if a combination of readily available variables improves the diagnosis of GIisch after cardiothoracic surgery. METHODS: This retrospective study included patients receiving intensive care after cardiothoracic surgery. GIisch was confirmed by surgical and/or endoscopic findings. A GIisch prediction score was developed using the Spiegelhalter-Knill-Jones system in a training cohort then tested in a validation cohort (patients without obvious signs of GIisch on CTA). RESULTS: The training cohort comprised 125 consecutive patients with suspected GIisch in 2008 to 2019, including 85 with confirmed GIisch. CTA, performed in 92 patients, had a high false-negative rate of 17/60 (28%) and a lower false-positive rate of 7/32 (22%). The score included cardiopulmonary bypass, negatively associated with GIisch, and six variables positively associated with GIisch: intraoperative mean arterial pressure < 50 mm Hg, aspartate aminotransferase > 15 N, lactate increase in 24 hour > 20%, and 3 CTA findings, namely, bowel dilation, bowel wall thickening, and mesenteric vasoconstriction. The area under the receiver operating characteristic was 0.82 (95% confidence interval [CI], 0.51-0.93) in the training cohort and 0.82 (95% CI, 0.68-0.96) in the validation cohort (n = 34 patients). Reliability of the predicted probabilities was greatest for probabilities ≤ 30% or ≥ 70%. CONCLUSION: In patients receiving intensive care after cardiothoracic surgery, GIisch cannot be ruled out based solely on CTA findings. A scoring system combining CTA findings with other variables may improve the diagnosis of GIisch in this population.

ESR Essentials: diagnosis of hepatocellular carcinoma-practice recommendations by ESGAR.

Hepatocellular carcinoma (HCC) is the most common primary hepatic malignancy and a leading cause of cancer related death worldwide. Current guidelines for the noninvasive diagnosis of HCC are provided by the European Association for the Study of the Liver (EASL), the American Association for the Study of Liver Diseases (AASLD) which endorsed the Liver Imaging Reporting and Data System (LI-RADS) algorithm, the Korean Liver Cancer Association-National Cancer Center (KLCA-NCC), and the Asian-Pacific Association for the Study of the Liver (APASL). These allow the diagnosis of HCC in high-risk patients in the presence of typical imaging features on contrast-enhanced CT, MRI, or contrast-enhanced ultrasound. Size, non-rim arterial phase hyperenhancement, non-peripheral washout, enhancing capsule, and growth are major imaging features and they should be combined for the diagnosis of HCC. This article provides concise and relevant practice recommendations aimed at general radiologist audience, summarizing the best practice and informing on the essential imaging criteria for the diagnosis of HCC, while also discussing the high-risk population criteria, imaging modalities, and imaging features according to the current guidelines. KEY POINTS: • Noninvasive diagnosis of hepatocellular carcinoma (HCC) can be provided only in patients at high risk. • Contrast-enhanced CT or MRI are the first-line imaging exams for the diagnosis of HCC. • Major imaging features should be combined to provide the diagnosis of definitive HCC.

French community grid for the evaluation of radiological artificial intelligence solutions (DRIM France Artificial Intelligence Initiative).

PURPOSE: The purpose of this study was to validate a national descriptive and analytical grid for artificial intelligence (AI) solutions in radiology. MATERIALS AND METHODS: The RAND-UCLA Appropriateness Method was chosen by expert radiologists from the DRIM France IA group for this statement paper. The study, initiated by the radiology community, involved seven steps including literature review, template development, panel selection, pre-panel meeting survey, data extraction and analysis, second and final panel meeting, and data reporting. RESULTS: The panel consisted of seven software vendors, three for bone fracture detection using conventional radiology and four for breast cancer detection using mammography. A consensus was reached on various aspects, including general target, main objective, certification marking, integration, expression of results, forensic aspects and cybersecurity, performance and scientific validation, description of the company and economic details, possible usage scenarios in the clinical workflow, database, specific objectives and targets of the AI tool. CONCLUSION: The study validates a descriptive and analytical grid for radiological AI solutions consisting of ten items, using breast cancer and bone fracture as an experimental guide. This grid would assist radiologists in selecting relevant and validated AI solutions. Further developments of the grid are needed to include other organs and tasks.

Complications of Mesh Sacrocolpopexy and Rectopexy: Imaging Review.

Sacrocolpopexy and rectopexy are commonly used surgical options for treatment of patients with pelvic organ and rectal prolapse, respectively. These procedures involve surgical fixation of the vaginal vault or the rectum to the sacral promontory with mesh material and can be performed independently of each other or in a combined fashion and by using an open abdominal approach or laparoscopy with or without robotic assistance. Radiologists can be particularly helpful in cases where patients' surgical histories are unclear by identifying normal sacrocolpopexy or rectopexy mesh material and any associated complications. Acute complications such as bleeding or urinary tract injury or stricture are generally evaluated with CT. More chronic complications such as mesh extrusion or exposure with or without fistulization to surrounding structures are generally evaluated with MRI. Other complications can have a variable time of onset after surgery. Patients with suspected bowel obstruction are generally evaluated with CT. Those with suspected infection, abscess formation, and discitis or osteomyelitis may be evaluated with MRI, although CT evaluation may be appropriate in certain scenarios. The authors review the sacrocolpopexy and rectopexy surgical techniques, discuss appropriate imaging protocols for evaluation of patients with suspected complications, and illustrate the normal appearance and common complications of these procedures. © RSNA, 2023 Quiz questions for this article are available in the supplemental material.

Postoperative surveillance of pancreatic ductal adenocarcinoma (PDAC) recurrence: practice pattern on standardized imaging and reporting from the society of abdominal radiology disease focus panel on PDAC.

PURPOSE: Surgical resection is the only potential curative treatment for patients with pancreatic ductal adenocarcinoma (PDAC), but unfortunately most patients recur within 5 years of surgery. This article aims to assess the practice patterns across major academic institutions and develop consensus recommendations for postoperative imaging and interpretation in patients with PDAC. METHODS: The consensus recommendations for postoperative imaging surveillance following PDAC resection were developed using the Delphi method. Members of the Society of Abdominal Radiology (SAR) PDAC Disease Focused Panel (DFP) underwent three rounds of surveys followed by live webinar group discussions to develop consensus recommendations. RESULTS: Significant variations currently exist in the postoperative surveillance of PDAC, even among academic institutions. Differentiating common postoperative inflammatory and fibrotic changes from tumor recurrence remains a diagnostic challenge, and there is no reliable size threshold or growth rate of imaging findings that can provide differentiation. A new liver lesion or peritoneal nodule should be considered suspicious for tumor recurrence, and the imaging features should be interpreted in the appropriate clinical context (e.g., CA 19-9, clinical presentation, pathologic staging). CONCLUSION: Postoperative imaging following PDAC resection is challenging to interpret due to the presence of confounding postoperative inflammatory changes. A standardized reporting template for locoregional findings and report impression may improve communication of relaying risk of recurrence with referring providers, which merits validation in future studies.

[The rôle of MRI in exploration anorectal pathologies]. / Place de l'IRM pour explorer les pathologies anorectales.

PLACE DE L'IRM POUR EXPLORER LES PATHOLOGIES ANORECTALES. L'imagerie par résonance magnétique (IRM) est l'un des examens d'imagerie les plus utiles à l'exploration des pathologies ano rectales. Elle est complémentaire de l'examen clinique et de l'endo scopie. Elle permet de fournir des données indispensables à une prise en charge optimale du patient par le proctologue, le chirurgien ou l'oncologue en fonction de la nature de l'atteinte anale ou rectale. Il est nécessaire de respecter les différentes indications de cet examen, qui ont été bien définies pour chaque pathologie par les différentes sociétés savantes. Le protocole de l'IRM varie en fonction de la zone explorée et de la pathologie suspectée. C'est pourquoi il est indispensable de fournir au radiologue les informations nécessaires telles que la suspicion diagnostique, les données cliniques, ainsi que les résultats des examens complémentaires déjà réalisés. Les indications les plus fréquentes de l'IRM en proctologie sont les tumeurs anales et rectales. L'IRM permet le bilan initial de l'extension locorégionale de la tumeur ainsi que le suivi oncologique précoce et tardif grâce à l'étude comparative des examens de surveillance par rapport au bilan initial. L'IRM est indispensable pour l'exploration des suppurations anopérinéales complexes, en particulier liées à la maladie de Crohn. Elle permet la réalisation du bilan lésionnel initial ainsi que le contrôle post-drainage. En cas de suspicion de maladie de Verneuil ou de sinus pilonidal infecté, l'IRM participe à l'orientation vers le diagnostic étiologique. La déféco-IRM est une variante particulière de l'IRM pelvienne et périnéale. Elle fait partie du bilan des dysfonctions du plancher pelvien, car elle permet l'étude du comportement des différents organes pelviens au cours des efforts de poussée et de défécation. Les fissures anales et les thromboses hémorroïdaires sont les causes les plus fréquentes de douleurs anales. Leur diagnostic est purement clinique. En cas d'examen proctologique normal, l'IRM sert à chercher une autre cause à ces douleurs.

THE ROLE OF MRI IN EXPLORATION ANORECTAL PATHOLOGIES. Magnetic resonance imaging (MRI) is one of the most useful imaging modalities for the exploration of anorectal pathologies. It is complementary to the clinical examination and endoscopy. It provides essential elements for optimal care of the patient by the proctologist, the surgeon or the oncologist depending on the nature of the anal or rectal condition. It is necessary to respect the different indications of this exam which have been well defined for each pathology by the different scientific societies. The MRI protocol varies depending on the site to be investigated and the pathology suspected. Therefore, it is essential to provide the radiologist with the necessary information such as the diagnostic suspicion, clinical findings, and the results of previous paraclinical examinations. MRI ensures the initial assessment of the locoregional extension of the tumor as well as the early and late oncological follow-up thanks to the comparative study of the surveillance examinations with the initial exam. MRI is essential for the assessment of complex anoperineal suppurations, in particular those related to Crohn's disease. It is necessary for the initial lesional assessment and for the post-drainage control. In case of suspicion of Verneuil's (hidradenitis suppurativa) disease or infected pilonidal sinus, MRI helps to orientate towards the right etiological diagnosis. MR defecating proctography is a particular variant of pelvic and perineal MRI. It is performed as part of the assessment of pelvic floor dysfunctions because it allows the study of the dynamics of the different pelvic organs during straining and defecation. Anal fissures and hemorrhoidal thrombosis are the most frequent etiologies of anal pain. Their diagnosis is purely clinical. If the proctological examination is normal, MRI is used to search for other causes of anal pain.

Epidemiological Study to Assess the Prevalence of Lung Cancer in patients with smoking-associated atherosclerotic cardiovascular diseases: PREVALUNG study protocol.

INTRODUCTION: Eligibility criteria definition for a lung cancer screening (LCS) is an unmet need. We hypothesised that patients with a history of atheromatous cardiovascular disease (ACVD) associated with tobacco consumption are at risk of lung cancer (LC). The main objective is to assess LC prevalence among patients with ACVD and history of tobacco consumption by using low-dose chest CT scan. Secondary objectives include the evaluation LCS in this population and the constitution of a biological biobank to stratify risk of LC. METHODS AND ANALYSIS: We are performing a monocentric 'single-centre' prospective study among patients followed up in adult cardiovascular programmes of vascular surgery, cardiology and cardiac surgery recruited from 18 November 2019 to 18 May 2021. The inclusion criteria are (1) age 45-75 years old, (2) history of ACVD and (3) history of daily tobacco consumption for 10 years prior to onset of ACVD. Exclusion criteria are symptoms of LC, existing follow-up for pulmonary nodule, fibrosis, pulmonary hypertension, resting dyspnoea and active pulmonary infectious disease. We targeted the inclusion of 500 patients. After inclusion (V0), patients are scheduled for a low-dose chest CT and blood and faeces harvesting within 7 months (V1). Each patient is scheduled for a follow-up by telephonic visits at month 3 (V2), month 6 (V3) and month 12 (V4) after V1. Each patient is followed up until 1 year after V1 (14 February 2023). We measure LC prevalence and quantify the National Lung Screening Trial and Dutch-Belgian Randomized Lung Cancer Screening Trial (NELSON) trial eligibility criteria, radiation, positive screening, false positivity, rate of localised LC diagnosis, quality of life with the Short Form 12 (SF-12) and anxiety with the Spielberger State-Trait Anxiety Inventory A and B (STAI-YA and STAI-YB, respectively), smoking cessation and onset of cardiovascular and oncological events within 1 year of follow-up. A case-control study nested in the cohort is performed to identify clinical or biological candidate biomarkers of LC. ETHICS AND DISSEMINATION: The study was approved according the French Jardé law; the study is referenced at the French 'Agence Nationale de Sécurité du Médicament et des Produits de Santé' (reference ID RCB: 2019-A00262-55) and registered on clinicaltrial.gov. The results of the study will be presented after the closure of the follow-up scheduled on 14 February 2023 and disseminated through peer-reviewed journals and national and international conferences. TRIAL REGISTRATION NUMBER: NCT03976804.

Head computed tomography for elderly patients with acute altered mental status in the emergency setting: value for decision-making and predictors of abnormal findings.

OBJECTIVE: This study evaluated the impact of head computed tomography (CT) on clinical decision-making about older adults with acute altered mental status (AMS) in the emergency department in terms of CT's diagnostic yield, emergency department length of stay, and changes in medical strategy. It also attempted to find predictors of an acute imaging abnormality. METHODS: This was a 1-year, retrospective, single-center observational study of patients aged ≥75 years who underwent noncontrast head CT because of an isolated episode of AMS. The acute positive CT findings were ischemic strokes, hemorrhages, tumors, demyelinating lesions, hydrocephalus, and intracranial infections. RESULTS: A total of 594 CTs were performed, of which 38 (6.4%) were positive. The main etiology of AMS was sepsis (29.1%). Changes in medical strategy were more common in patients with a positive CT, and the major changes were ordering additional neuro exams (odds ratio [OR], 95.3; 95% confidence interval [CI], 38.4-233.8; P<0.001), adjusting treatments (OR, 12.2; 95% CI, 5.0-29.5; P<0.001), and referral to a neurologic unit (OR, 7.3; 95% CI, 3.0-17.5; P<0.01). Three factors were significantly associated with a positive outcome: Glasgow Coma Scale <13 (OR, 8.5; 95% CI, 2.3-28.9; P<0.001), head wound (OR, 3.1; 95% CI, 1.1-8.2; P=0.025), and dehydration (OR, 0.3; 95% CI, 0.1-0.4; P=0.021). For elderly patients with a Glasgow Coma Scale ≥13 and no head wound or clinical dehydration, the probability of a positive CT was 0.02 (95% CI, 0.01-0.04). Considering only those patients, the diagnostic yield fell to 1.7%. CONCLUSION: In elderly patients, the causes of AMS are primarily extracerebral. Randomized clinical trials are needed to validate a clinical pathway for selecting patients who require emergent neuroimaging.

Diffuse Involvement of Pancreas is not Always Autoimmune Pancreatitis.

RATIONALE AND OBJECTIVES: To determine the prevalence of diffuse involvement of pancreas and to identify the findings of malignancies using enhancement computed tomography (CT). MATERIALS AND METHODS: A total of 1,0249 patients performed enhancement CT in our hospital over 62 months were investigated and the final study cohort includes 245 patients (170 males, 75 females; mean age, 56.94 ± 12.17 years). The reference standard is the final clinical/pathological diagnosis. The lesion-to-aorta enhancement ratio (LAR) on the pancreatic arterial phase, portal phase and delayed phase (DP) and the traditional CT findings were evaluated. Intergroup comparisons between malignancies and non-malignancies lesions were performed. Univariate and multivariate analyses were conducted to identify findings predicting malignancies. RESULTS: The prevalence of malignancy was 45.3% (111/245) of diffuse enlargement of pancreas. All benign lesions were autoimmune pancreatitis 54.7% (n = 134). The most common malignant lesion was pancreatic ductal adenocarcinoma (n = 88, 35.9%). Other rare lesions with malignant potential included pancreatic neuroendocrine tumor (n = 11, 4.5%), lymphoma (n = 4, 1.6%), metastasis (n = 4, 1.6%), solid pseudopapillary neoplasm (n = 3, 1.2%) and acinar cell carcinoma (n = 1, 0.4%). Residual normal pancreas parenchyma, heterogeneity, short axis (cut-off value, 3.15 cm) and LARDP (cut-off value, 0.75) were independent predictors of malignancies. When the above predictors were combined, a sensitivity of 94.2%, a specificity of 90.8% were attained. CONCLUSION: Diffuse involvement of the pancreas is rare and is not a specific sign of autoimmune pancreatitis, and it is associated with a wide spectrum of malignant conditions. Dynamic enhancement CT is helpful to identifying malignancies.

Fractal analysis improves tumour size measurement on computed tomography in pancreatic ductal adenocarcinoma: comparison with gross pathology and multi-parametric MRI.

OBJECTIVES: Tumour size measurement is pivotal for staging and stratifying patients with pancreatic ductal adenocarcinoma (PDA). However, computed tomography (CT) frequently underestimates tumour size due to insufficient depiction of the tumour rim. CT-derived fractal dimension (FD) maps might help to visualise perfusion chaos, thus allowing more realistic size measurement. METHODS: In 46 patients with histology-proven PDA, we compared tumour size measurements in routine multiphasic CT scans, CT-derived FD maps, multi-parametric magnetic resonance imaging (mpMRI), and, where available, gross pathology of resected specimens. Gross pathology was available as reference for diameter measurement in a discovery cohort of 10 patients. The remaining 36 patients constituted a separate validation cohort with mpMRI as reference for diameter and volume. RESULTS: Median RECIST diameter of all included tumours was 40 mm (range: 18-82 mm). In the discovery cohort, we found significant (p = 0.03) underestimation of tumour diameter on CT compared with gross pathology (Δdiameter3D = -5.7 mm), while realistic diameter measurements were obtained from FD maps (Δdiameter3D = 0.6 mm) and mpMRI (Δdiameter3D = -0.9 mm), with excellent correlation between the two (R2 = 0.88). In the validation cohort, CT also systematically underestimated tumour size in comparison to mpMRI (Δdiameter3D = -10.6 mm, Δvolume = -10.2 mL), especially in larger tumours. In contrast, FD map measurements agreed excellently with mpMRI (Δdiameter3D = +1.5 mm, Δvolume = -0.6 mL). Quantitative perfusion chaos was significantly (p = 0.001) higher in the tumour rim (FDrim = 4.43) compared to the core (FDcore = 4.37) and remote pancreas (FDpancreas = 4.28). CONCLUSIONS: In PDA, fractal analysis visualises perfusion chaos in the tumour rim and improves size measurement on CT in comparison to gross pathology and mpMRI, thus compensating for size underestimation from routine CT. KEY POINTS: • CT-based measurement of tumour size in pancreatic adenocarcinoma systematically underestimates both tumour diameter (Δdiameter = -10.6 mm) and volume (Δvolume = -10.2 mL), especially in larger tumours. • Fractal analysis provides maps of the fractal dimension (FD), which enable a more reliable and size-independent measurement using gross pathology or multi-parametric MRI as reference standards. • FD quantifies perfusion chaos-the underlying pathophysiological principle-and can separate the more chaotic tumour rim from the tumour core and adjacent non-tumourous pancreas tissue.

Imaging Assessment of Pancreatic Cancer Resectability After Neoadjuvant Therapy: AJR Expert Panel Narrative Review.

Despite important innovations in the treatment of pancreatic ductal adenocarcinoma (PDAC), PDAC remains a disease with poor prognosis and high mortality. A key area for potential improvement in the management of PDAC, aside from earlier detection in patients with treatable disease, is the improved ability of imaging techniques to differentiate treatment response after neoadjuvant therapy (NAT) from worsening disease. It is well established that current imaging techniques cannot reliably make this distinction. This narrative review provides an update on the imaging assessment of pancreatic cancer resectability after NAT. Current definitions of borderline resectable PDAC, as well as implications for determining likely patient benefit from NAT, are described. Challenges associated with PDAC pathologic evaluation and surgical decision making that are of relevance to radiologists are discussed. Also explored are the specific limitations of imaging in differentiating the response after NAT from stable or worsening disease, including issues relating to protocol optimization, tumor size assessment, vascular assessment, and liver metastasis detection. The roles of MRI as well as PET and/or hybrid imaging are considered. Finally, a short PDAC reporting template is provided for use after NAT. The highlighted methods seek to improve radiologists' assessment of PDAC treatment response after NAT.

Pre-surgical and Post-surgical Aortic Aneurysm Maximum Diameter Measurement: Full Automation by Artificial Intelligence.

OBJECTIVE: The aim of this study was to evaluate an automatic, deep learning based method (Augmented Radiology for Vascular Aneurysm [ARVA]), to detect and assess maximum aortic diameter, providing cross sectional outer to outer aortic wall measurements. METHODS: Accurate external aortic wall diameter measurement is performed along the entire aorta, from the ascending aorta to the iliac bifurcations, on both pre- and post-operative contrast enhanced computed tomography angiography (CTA) scans. A training database of 489 CTAs was used to train a pipeline of neural networks for automatic external aortic wall measurements. Another database of 62 CTAs, including controls, aneurysmal aortas, and aortic dissections scanned before and/or after endovascular or open repair, was used for validation. The measurements of maximum external aortic wall diameter made by ARVA were compared with those of seven clinicians on this validation dataset. RESULTS: The median absolute difference with respect to expert's measurements ranged from 1 mm to 2 mm among all annotators, while ARVA reported a median absolute difference of 1.2 mm. CONCLUSION: The performance of the automatic maximum aortic diameter method falls within the interannotator variability, making it a potentially reliable solution for assisting clinical practice.

European Cancer Organisation Essential Requirements for Quality Cancer Care (ERQCC): Pancreatic Cancer.

European Cancer Organisation Essential Requirements for Quality Cancer Care (ERQCC) are written by experts representing all disciplines involved in cancer care in Europe. They give patients, health professionals, managers and policymakers a guide to essential care throughout the patient journey. Pancreatic cancer is an increasing cause of cancer mortality and has wide variation in treatment and care in Europe. It is a major healthcare burden and has complex diagnosis and treatment challenges. Care must be carried out only in pancreatic cancer units or centres that have a core multidisciplinary team (MDT) and an extended team of health professionals detailed here. Such units are far from universal in European countries. To meet European aspirations for comprehensive cancer control, healthcare organisations must consider the requirements in this paper, paying particular attention to multidisciplinarity and patient-centred pathways from diagnosis, to treatment, to survivorship.

Pneumatosis intestinalis and portal venous gas in mechanical small bowel obstruction: Is it worrisome?

PURPOSE: The purpose of this study was to evaluate the clinical significance of pneumatosis intestinalis (PI) and portal venous gas (PVG) in patients with mechanical small bowel obstruction (SBO), using surgical findings or clinical follow-up as standard of reference. MATERIALS AND METHODS: Fourteen patients with mechanical SBO associated with PI and PVG were retrospectively included. There were 7 men and 7 women with a mean age of 59±19 (SD) (range: 25-93 years). CT examinations were reviewed by two radiologists to confirm the diagnosis of mechanical SBO and make a description of PI. Interobserver agreement was calculated. The reference standard was intraoperative appearance of the bowel wall (10/14; 71%) or the recovery of a normal bowel function in patients who were managed conservatively (4/14; 29%). RESULTS: Among the 10 patients who underwent surgery, a normal appearance of the bowel in association with PI on CT was found intraoperatively in 8/10 (80%) patients and a reversible ischemia in the remaining 2/10 (20%) patients. The four patients who were managed conservatively recovered normal bowel function. Two patients died within two weeks following SBO. CONCLUSION: PI and PVG are not specific signs of bowel necrosis in mechanical SBO.

Therapeutic response assessment in pancreatic ductal adenocarcinoma: society of abdominal radiology review paper on the role of morphological and functional imaging techniques.

Pancreatic ductal adenocarcinoma (PDA) is the third leading cause of cancer-related death in the United States and is projected to be the second by 2030. Systemic combination chemotherapy is considered an essential first-line treatment for the majority of patients with PDA, in both the neoadjuvant and palliative settings. In addition, a number of novel therapies are being tested in clinical trials for patients with advanced PDA. In all cases, accurate and timely assessment of treatment response is critical to guide therapy, reduce drug toxicities and cost from a failing therapy, and aid adaptive clinical trials. Conventional morphological imaging has significant limitations, especially in the context of determining primary tumor response and resectability following neoadjuvant therapies. In this article, we provide an overview of current therapy options for PDA, highlight several morphological imaging findings that may be helpful to reduce over-staging following neoadjuvant therapy, and discuss a number of emerging imaging, and non-imaging, tools that have shown promise in providing a more precise quantification of disease burden and treatment response in PDA.

Adhesive Small Bowel Obstruction: Predictive Radiology to Improve Patient Management.

Adhesive small bowel obstruction (SBO) remains one of the leading causes of emergency room visits and is still associated with high morbidity and mortality rates. Because the management of adhesive SBO has shifted from immediate surgery to nonoperative treatment in the absence of ischemia, it is crucial to rapidly detect or predict strangulation, which requires emergent surgery. CT is now established as the best imaging technique for the initial assessment of patients suspected of having adhesive SBO. CT helps confirm the diagnosis of mechanical SBO, locate the site of obstruction, establish the cause, and detect complications. This article is a review of the role of imaging in answering specific questions to help predict the management needs of each individual patient. It includes (a) an update on the best CT signs for predicting ischemia and a need for bowel resection; (b) a discussion of the CT features that help differentiate open-loop from closed-loop obstruction and a single adhesive band from matted adhesions and how these differences can influence the management; and (c) a review of the main CT predictors of the success or failure of nonoperative management in adhesive SBO.

CT diagnosis of closed loop bowel obstruction mechanism is not sufficient to indicate emergent surgery.

PURPOSE: To identify computed tomography (CT) findings associated with successful conservative treatment of closed loop small bowel obstruction (CL-SBO) due to adhesions or internal herniation. MATERIAL AND METHODS: The local institutional review board approved this study while waiving informed consent. Clinical and CT data were collected retrospectively for 96 consecutive patients with a CT diagnosis of CL-SBO due to adhesions or internal herniation established by experienced radiologists who had no role in patient management. Mechanical obstruction with at least two transition zones on the bowel at a single site defined CL-SBO. Two radiologists blinded to patient data independently performed a retrospective review of the CT scans. The patient groups with successful versus failed initial conservative therapy were compared. Univariate and multivariate analyses were performed to look for CT findings associated with successful conservative therapy. Interobserver agreement was assessed for each CT finding. RESULTS: Of the 96 patients, 34 (35%) underwent immediate surgery and 62 (65%) received first-line conservative treatment, which succeeded in 19 (31%) and failed in 43 (69%). The distance between the transition zones was the only independent predictor of successful conservative therapy (odds ratio, 4.6 when ≥ 8 mm; 95% confidence interval [95% CI], 1.2-18.3). A distance ≥ 8 mm had 84% (95% CI, 60-97) sensitivity and 46% (95% CI, 31-62) specificity for successful conservative treatment. The correlation coefficient for the distance between transition zones between readers 1 and 2 was fair (r = 0.46). CONCLUSION: CL-SBO can be resolved without surgery. When there is no CT sign of ischemia, the distance between the transition zones should be assessed. KEY POINTS: • Twenty percent (19/96) of all cases of closed loop small bowel obstruction (CL-SBO) representing 31% of the patients given first-line conservative therapy, were resolved without surgery. • The distance between the transition zones may help to choose between conservative and surgical management in patients with a CL-SBO but no CT evidence of ischemia. • A distance < 8 mm between the transition zones suggests a need for emergent surgery.