Features of infective native aortic aneurysms on computed tomography

Background Infective native aortic aneurysm (INAA) is a rare clinical diagnosis. The purpose of this study was to describe the CT findings of INAAs in detail. Methods This was a retrospective single-center study of INAA patients at a major referral hospital between 2005 and 2020. All images were reviewed according to a protocol consisting of aneurysm features, periaortic findings, and associated surrounding structures. Results One hundred and fourteen patients (mean age, 66 years [standard deviation, 11 years]; 91 men) with 132 aneurysms were included. The most common locations were infrarenal (50.8%), aortoiliac (15.2%), and juxtarenal (12.9%). The mean transaxial diameter was 6.2 cm. Most INAAs were saccular (87.9%) and multilobulated (91.7%). Calcified aortic plaque was present in 93.2% and within the aneurysm in 51.5%. INAA instability was classified as contained rupture (27.3%), impending rupture (26.5%), and free rupture (3.8%). Rapid expansion was demonstrated in 13 of 14 (92.9%) aneurysms with sequential CT studies. Periaortic inflammation was demonstrated as periaortic enhancement (94.7%), fat stranding (93.9%), soft-tissue mass (92.4%), and lymphadenopathy (62.1%). Surrounding involvement included psoas muscle (17.8%), spondylitis (11.4%), and perinephric region (2.8%). Twelve patients demonstrated thoracic and abdominal INAA complications: fistulas to the esophagus (20%), bronchus (16%), bowel (1.9%), and inferior vena cava (IVC) (0.9%). Conclusion The most common CT features of INAA were saccular aneurysm, multilobulation, and calcified plaques. The most frequent periaortic findings were enhancement, fat stranding, and soft-tissue mass. Surrounding involvement, including psoas muscle, IVC, gastrointestinal tract, and bronchi, was infrequent but may develop as critical INAA complications.

Diagnostic Accuracy of Imaging Findings in Pleural Empyema: Systematic Review and Meta-Analysis

Computed tomography (CT) diagnosis of empyema is challenging because current literature features multiple overlapping pleural findings. We aimed to identify informative findings for structured reporting. The screening according to inclusion criteria (P: Pleural empyema, I: CT C: culture/gram-stain/pathology/pus, O: Diagnostic accuracy measures), data extraction, and risk of bias assessment of studies published between 01-1980 and 10-2021 on Pubmed, Embase, and Web of Science (WOS) were performed independently by two reviewers. CT findings with pooled diagnostic odds ratios (DOR) with 95% confidence intervals, not including 1, were considered as informative. Summary estimates of diagnostic accuracy for CT findings were calculated by using a bivariate random-effects model and heterogeneity sources were evaluated. Ten studies with a total of 252 patients with and 846 without empyema were included. From 119 overlapping descriptors, five informative CT findings were identified: Pleural enhancement, thickening, loculation, fat thickening, and fat stranding with an AUC of 0.80 (hierarchical summary receiver operating characteristic, HSROC). Potential sources of heterogeneity were different thresholds, empyema prevalence, and study year.

Periappendiceal fat-stranding models for discriminating between complicated and uncomplicated acute appendicitis: a diagnostic and validation study

Background Recent studies have reported promising outcomes of non-operative treatment for uncomplicated appendicitis; however, the preoperative prediction of complicated appendicitis is challenging. We developed models by incorporating fat stranding (FS), which is commonly observed in perforated appendicitis. Material and methods We reviewed the data of 402 consecutive patients with confirmed acute appendicitis from our prospective registry. Multivariate logistic regression was performed to select clinical and radiographic factors predicting complicated acute appendicitis in our model 1 (involving backward elimination) and model 2 (involving stepwise selection). We compared c statistics among scoring systems developed by Bröker et al. (in J Surg Res 176(1):79–83. https://doi.org/10.1016/j.jss.2011.09.049, 2012), Imaoka et al. (in World J Emerg Surg 11(1):1–5, 2016), Khan et al. (in Cureus. https://doi.org/1010.7759/cureus.4765, 2019), Kim et al. (in Ann Coloproctol 31(5):192, 2015), Kang et al. (in Medicine 98(23): e15768, 2019), Atema et al. (in Br J Surg 102(8):979–990. https://doi.org/10.1002/bjs.9835, 2015), Avanesov et al. (in Eur Radiol 28(9):3601–3610, 2018), and Kim et al. (in Abdom Radiol 46:1–12, 2020). Finally, we examined our models by performing the integrated discrimination improvement (IDI) test. Results Among enrolled patients, 64 (15.9%) had complicated acute appendicitis. We developed new 10-point scoring models by including the following variables: C-reactive protein, neutrophil to lymphocyte ratio, and computed tomography features of FS, ascites, and appendicolith. A cutoff score of ≥ 6 exhibited a high sensitivity of 82.8% and a specificity of 82.8% for model 1 and 81.3% and 82.3% for model 2, respectively, with c statistics of 0.878 (model 1) and 0.879 (model 2). Compared with the model developed by Bröker et al. which included C-reactive protein and the abdominal pain duration (c statistic: 0.778), the models developed by Atema et al. (c statistic: 0.826, IDI: 5.92%, P = 0.0248), H.Y Kim et al. (c statistics: 0.838, IDI: 13.82%, P = 0.0248), and our two models (IDI: 18.29%, P < 0.0001) demonstrated a significantly higher diagnostic accuracy. Conclusion Our models and the scoring systems developed by Atema et al. and Kim et al. were validated to have a high diagnostic accuracy; moreover, our models included the lowest number of variables.

EP.FRI.971 Is routine endoscopic evaluation of the colon necessary after an episode of acute diverticulitis?

Aim Currently standard practice is for patients diagnosed with diverticulitis to undergo endoscopic evaluation of the colon following the acute episode. The primary aim of endoscopy is to exclude underlying malignancy which may have been undetectable on initial CT scanning. We aim to determine if endoscopic evaluation of the colon is necessary for all patients. Methods All patients with CT proven diverticulitis were included between May 2017 and July 2018. Medical records, CT and endoscopy reports of 154 consecutive patients were retrospectively reviewed. Based on the CT reports, diverticulitis was classified as either uncomplicated (colonic wall thickening, pericolic fat stranding) or complicated (perforation, abscess, generalised free air and/or fluid). Results There were 154 patients included in the study. 59% percent were male. Median age at the time of diagnosis was 56 years old. There were 114 patients with uncomplicated and 40 patients with complicated diverticulitis. 79 patients (50 flexible sigmoidoscopy, 29 colonoscopy) with uncomplicated diverticulitis and 21 patients (15 flexible sigmoidoscopy, 6 colonoscopy) with complicated diverticulitis underwent endoscopy. Of the patients that underwent endoscopy, one patient (1.3%) with uncomplicated disease and one patient (4.8%) with complicated disease were found to have colorectal cancer (both rectal). Neither of these were associated with the diverticular segment. Conclusions Our data shows that routine endoscopic evaluation of the colon after an episode of acute diverticulitis may not be necessary in all cases. Patient numbers in this study are small therefore further work is required to draw conclusions which could influence future clinical practice.

Pre-Operative MDCT Staging Predicts Mesopancreatic Fat Infiltration—A Novel Marker for Neoadjuvant Treatment?

Summary: The rates of microscopic incomplete resections (R1/R0CRM+) in patients receiving standard pancreaticoduodenectomy for PDAC remain very high. One reason may be the reported high rates of mesopancreatic fat infiltration. In this large cohort study, we used available histopathological specimens of the retropancreatic fat and correlated high resolution CT-scans with the microscopic tumor infiltration of this area. We found that preoperative MDCT scans are suitable to detect cancerous infiltration of this mesopancreatic tissue and this, in turn, was a significant indicator for both incomplete surgical resection (R1/R0CRM+) and worse overall survival. These findings indicate that a neoadjuvant treatment in PDAC patients with CT-morphologically positive infiltration of the mesopancreas may result in better local control and thus improved resection rates. Mesopancreatic fat stranding should thus be considered in the decision for neoadjuvant therapy. Background: Due to the persistently high rates of R1 resections, neoadjuvant treatment and mesopancreatic excision (MPE) for ductal adenocarcinoma of the pancreatic head (hPDAC) have recently become a topic of interest. While radiographic cut-off for borderline resectability has been described, the necessary extent of surgery has not been established. It has not yet been elucidated whether pre-operative multi-detector computed tomography (MDCT) staging reliably predicts local mesopancreatic (MP) fat infiltration and tumor extension. Methods: Two hundred and forty two hPDAC patients that underwent MPE were analyzed. Radiographic re-evaluation was performed on (1) mesopancreatic fat stranding (MPS) and stranding to peripancreatic vessels, as well as (2) tumor diameter and anatomy, including contact to peripancreatic vessels (SMA, GDA, CHA, PV, SMV). Routinely resected mesopancreatic and perivascular (SMA and PV/SMV) tissue was histopathologically re-analyzed and histopathology correlated with radiographic findings. A logistic regression of survival was performed. Results: MDCT-predicted tumor diameter correlated with pathological T-stage, whereas presumed tumor contact and fat stranding to SMA and PV/SMV predicted and correlated with histological cancerous infiltration. Importantly, mesopancreatic fat stranding predicted MP cancerous infiltration. Positive MP infiltration was evident in over 78%. MPS and higher CT-predicted tumor diameter correlated with higher R1 resection rates. Patients with positive MP stranding had a significantly worse overall survival (p = 0.023). Conclusions: A detailed preoperative radiographic assessment can predict mesopancreatic infiltration and tumor morphology and should influence the decision for primary surgery, as well as the extent of surgery. To increase the rate of R0CRM− resections, MPS should be considered in the decision for neoadjuvant therapy.

Determinants of pyelonephritis onset in patients with obstructive urolithiasis

Background: Acute obstructive pyelonephritis due to urolithiasis represents a medico-surgical emergency that can lead to life-threatening complications. There are still no established factors that reliably predict progression toward acute pyelonephritis in patients presenting with a simple renal colic. Objective: To investigate clinical and paraclinical factors that are associated with the onset of acute obstructive pyelonephritis. Methods: Patients presenting to the emergency department for renal colic with obstructive urolithiasis on imaging were enrolled in the study. Demographic data, vital signs, medical comorbidities, blood test results, urinalysis, and radiological findings were recorded. Obstructive pyelonephritis was defined by the presence of two or more of the following criteria: fever, flank pain or costovertebral angle tenderness, and a positive urine culture. Results: Seventeen patients out of 120 presenting with renal colic, were diagnosed with acute obstructive pyelonephritis (14%). Parameters that were associated with the onset of obstructive pyelonephritis were: diabetes ( p = 0.03), elevated CRP ( p = 0.01), stone size (>5 mm) ( p = 0.03), dilatation of renal pelvis ( p = 0.01), peri-renal fat stranding ( p = 0.02), and positive nitrites on urinalysis ( p < 0.01). Hyperleukocytosis, acute kidney injury, multiple stones, pyuria (>10/mm3), hypertension, and were not associated with the onset of obstructive pyelonephritis. Conclusion: This study showed that known diabetic status, elevated CRP, positive urine nitrites, stone size (>5 mm), pyelic dilatation, and peri-renal fat stranding were associated with the onset of pyelonephritis in patients presenting to the emergency department with obstructive urolithiasis.

Undetected Pancreatic Adenocarcinoma on CT: Frequency According to CT Scan Protocol

Purpose: CT is a main diagnostic modality for detecting pancreatic adenocarcinoma. This study aims to assess the frequency of missed pancreatic adenocarcinoma on CT scans according to different CT protocols.Methods: Consecutive pancreatic adenocarcinoma patients were retrospectively collected (12/2011-12/2015). Patients with abdominal CT scans performed up-to a year prior to cancer diagnosis were included. Two radiologists registered in consensus the presence and radiological signs of missed cancers. The frequency of missed cancers was compared between portal and pancreatic/triphasic CT protocols. Results: Overall, 180 CT scans of pancreatic adenocarcinoma patients were retrieved. 126/180 (70.0%) were pancreatic/triphasic protocols and 54/180 (30.0%) were portal protocols. The overall frequency of missed cancers was 6/180 (3.3%). The frequency of missed cancers was higher in portal CT protocols compared to pancreatic/triphasic protocols: 5/54 (9.3%) vs. 1/126 (0.8%), p=0.01. CT signs of missed cancers included: 3 cases of small hypodense lesions, 2 cases with peri-pancreatic fat stranding, 1 case of dilated pancreatic duct with a cut-off sign.Conclusion: The frequency of missed pancreatic adenocarcinoma is higher on portal CT protocols. Physicians should consider the cancer miss rate on different CT protocols.

Orbital pseudotumor masquerading orbital cellulitis

Here with presenting a case of pseudotumor orbit initially diagnosed as orbital cellulitis which responded to steroids. A 44 year old male presented with complaints of swelling, redness, watering and inability to open the right eye for 1 day. He had no h/o trauma or insect bite. On examination, visual acuity in both eyes was 6/6. The right eye was proptosed with gross restriction of the extra ocular movements, conjunctival congestion and chemosis. The intra ocular pressure was 52 mm Hg. The left eye was normal. CT orbit showed enlargement of right lateral rectus muscle and lacrimal gland, with fat stranding and soft tissue thickening of periorbital, pre septal and perinasal regions diagnostic of pseudotumor tumour. He was started on high dose oral steroids with which he improved dramatically.