Research Presentation Session: Abdominal Viscera & GI Tract

RPS 2101 - Acute abdominal pathologies: diagnosis and prediction

March 2, 16:00 - 17:30 CET

7 min
Dual-Energy CT of acute bowel ischaemia: influence on diagnostic accuracy and reader confidence
Moritz Oberparleiter, Basel / Switzerland
Author Block: M. Oberparleiter, J. Vosshenrich, H-C. Breit, B. Friebe, D. Harder, D. Boll, C. J. Zech, M. Obmann; Basel/CH
Purpose: Current guidelines do not recommend the use of Dual-Energy CT (DECT) for suspected acute mesenteric ischaemia due to a lack of clinical studies. The purpose of this study was to investigate the diagnostic accuracy, reader confidence and reading time of DECT compared to conventional CT.
Methods or Background: 25 patients with surgically proven acute mesenteric ischaemia and 25 gender- and age-matched controls, who underwent arterial and portal venous phase DECT of the abdomen were included in this retrospective study. Two fellowship-trained abdominal radiologists evaluated all cases with and without the use of DECT-derived virtual non-contrast images and iodine maps for mesenteric ischaemia. Reading time was recorded and diagnostic confidence was rated on a 10-point Likert scale. The inter-reader agreement was assessed using Cohen's kappa. Sensitivity and specificity were compared using McNemar’s test, reading time and reader confidence with the Wilcoxon rank-sum test.
Results or Findings: Inter-reader agreement was good (𝜅=0.72). Sensitivity and specificity for diagnosing acute mesenteric ischaemia were 78% and 100% using conventional image data alone. Utilising additional DECT data, sensitivity was significantly higher at 94% (p=0.02), while specificity remained 100%. Diagnostic confidence increased significantly from 8 (IQR, 7-10) to 9 (IQR, 8-10) (p<0.01). Mean reading time per case increased significantly from 154 to 183 s (p=0.02) using additional DECT images.
Conclusion: Additional use of DECT should be considered when examining for suspected acute mesenteric ischaemia as DECT increased reader diagnostic accuracy and confidence for mesenteric ischaemia with only a moderate increase in reading time.
Limitations: Only two DECT scanner types were used in this study and results may not be transferable to other DECT platforms. Readers who are familiar with DECT technology may benefit while inexperienced readers may benefit less from DECT images.
Funding for this study: This research received no specific grant from any funding agency in the public, commercial or non-profit sectors.
Has your study been approved by an ethics committee? Yes
Ethics committee - additional information: The need for informed consent was waived due to the retrospective nature of this study.
7 min
Hit and miss: locating the exact site of gastrointestinal tract perforations as a challenge
Tarik Binasa Plojović, Belgrade / Serbia
Author Block: T. B. Plojović, A. Pavlovic, D. Markovic, D. Janjic, J. Vukmirovic, K. Lazarevic, B. Jovandić, D. Vasin, S. Hasanagic; Belgrade/RS
Purpose: The objective of our study was to analyse the capacity of CT (Computerized Tomography) to identify the site of gastrointestinal perforation (GI) and to determine which radiological signs, either direct or indirect, are the most predictive.
Methods or Background: Between September 2022 and September 2023, we retrospectively studied 100 patients presenting with pneumoperitoneum on CT. All patients had surgically proven gastrointestinal tract perforation. Two expert radiologists, with no previous knowledge of the clinical histories or the surgical results, evaluated the CT scans.
Results or Findings: The locations of the perforations found during surgery in the 100 patients were as follows: 36 stomach or duodenum; 15 small intestine; 12 appendix; 16 ascending, transverse or descending colon; and 21 sigma/rectum. The Kappa correlation coefficient between radiologists for predicting the localisation of the perforation in our study was high. The two most frequent signs observed in our study were free extraluminal air in the supramesocolic space and gas bubbles adjacent to the wall. The prediction of the perforation site in the gastrointestinal tract using CT coincided with the surgical findings in 80 out of 100 patients. In 20 patients, the prediction did not concur with the findings. In 15 cases, CT identified an incorrect perforation site while in 5 patients, CT did not identify the location of the GI perforation. The most sensitive sign in our study was the presence of free extraluminal air in the supramesocolic compartment. The most specific ones were the presence of abscesses and focal wall defects.
Conclusion: CT can locate gastrointestinal perforation sites with a high sensitivity and excellent interobserver correlation.
Limitations: This was a retrospective study.
Funding for this study: No funding was received for this study.
Has your study been approved by an ethics committee? Yes
Ethics committee - additional information: This study was approved by the Institutional Ethics Committee.
7 min
CT prognostic signs in emergency surgery for acute obstructive colonic cancer (AOCC)
Rosita Comune, Napoli / Italy
Author Block: F. Pezzullo1, S. Tamburrini1, R. Comune1, R. D'avino1, C. Liguori1, M. Scaglione2, F. Tamburro1; 1Naples/IT, 2Sassari/IT
Purpose: This study aimed to identify CT prognostic signs of poor outcomes of emergency surgery in AOCC.
Methods or Background: Demographic, clinical, laboratory, radiological and surgical data of 65 consecutive patients with AOCC who underwent emergency surgery were analysed. CTs were reviewed to assess the diameters of the cecum, ascending, transverse, descending, and sigmoid proximal to the tumour. Furthermore, colon segments’ CD/L1-VD ratios, continence of the ileocecal valve, small bowel over-distension, presence of faecal signs and cecal pneumatosis were also analysed. Postoperative complications, according to Clavien-Dindo classifications, were used.
Results or Findings: Preoperative transverse and descending colon CD/L1-VD ratios were significantly associated with the development of postoperative complications with a cut-off value of >/=1.4 and 1.3 (p=0.157 and p=0.008 - Clavien-Dindo classification major - grade ≥III-V), respectively. Postoperative complications within 30 days after surgery occurred in 18/65 patients, with 12 patients developing surgical complications (18.5%), 3 patients developing medical complications (4.6%) and 3 patients dying (4.6%). Of the 18 patients, 15 (23,1%) developed severe complications (grade ≥III-V).
A cecum distension >/= 9 cm represented the critical dimension beyond which perforation and cecal necrosis were found at surgery (11/65 patients). Cecal pneumatosis was detected in 5/11 patients.
Conclusion: CT is a valid tool to select patients at higher risk of complications. A CD/L1-VD ratio with cut-off values of 1.4 (transverse) and 1.3 (descending) predicted major complications (grade ≥III-V). A cecum diameter >/= 9 cm and continence of ileo cecal valve were predictive factors of poor outcome and cecal necrosis. The CT sign of cecal pneumatosis was not pathognomonic for cecal necrosis.
Limitations: This was a retrospective study and prospective multicenter studies are needed to validate our results.
Funding for this study: No funding was received for this study.
Has your study been approved by an ethics committee? Yes
Ethics committee - additional information: This study was approved by the local Institutional Review Board. The Ethical Committee approval was obtained (2022030). Patient consent was waived (Retrospective Observational Study).
7 min
(HU)nt for truth: psoas muscle evaluation on CT imaging predicts 30-day survival in variceal bleed patients
Jędrzej Krawczyk, London / United Kingdom
Author Block: J. Krawczyk, D. Leon, L. D. Tyson, T. Haq, D. Saba, R. H. Thomas, A. Dhar; London/UK
Purpose: This study aimed to assess if sarcopenia defined on cross-sectional imaging predicts 30-day mortality in the setting of variceal bleeding, independent of baseline liver disease severity.
Methods or Background: A retrospective study was performed of all patients with decompensated cirrhosis admitted with a variceal bleed over a 24-month period to our tertiary centre. CT imaging acquired within 3 months of admission was reviewed to determine psoas muscle thickness, width, area and Hounsfield Units (HU: a surrogate measure of psoas density) at the level of the inferior L4 endplate. The area of the psoas was calculated using a generic lesion segmentation tool and the average HU value was calculated from circular ROI in the area of the muscle. Association with 30-day mortality was tested by univariate and multivariate binary logistic regression; and the utility of identified prognostic biomarkers by AUROC analyses (SPSS v 27).
Results or Findings: 104 patients with decompensated cirrhosis were identified with variceal bleed episodes. 15/104 died within 30 days. As expected, a higher MELD score was associated with higher mortality (OR 1.106, 95% CI 1.034-1.183, P=0.003). Higher Psoas HU and PMTH were both associated with lower mortality, independent of MELD (Adjusted OR 0.891, 0.821-0.967, P=0.006; AOR 0.810, 0.665-0.987, P=0.036 respectively). Psoas HU was predictive of 30-day survival (AUROC 0.790, 0.673-0.907, P=0.004) as was PMTH (AUROC 0.743, 0.571-0.914, P=0.017), and MELD (AUROC 0.719, 0.534-0.904, P=0.008).
Conclusion: Psoas HU and PMTH are negatively associated with mortality in patients with decompensated cirrhosis and variceal bleeding. Crucially, this relationship appears independent of baseline liver disease severity (MELD score).
Limitations: Larger studies are needed to confirm the association of Psoas HU and PMTH with 30-day mortality and to further define the role of these parameters as prognostic indexes in this clinical setting.
Funding for this study: No funding was received for this study.
Has your study been approved by an ethics committee? Not applicable
Ethics committee - additional information: No information provided by the submitter.
7 min
Diagnostic impact of AAST injury scale in the assessment of hepatic traumatic lesions
Cesare Maino, Monza / Italy
Author Block: C. Maino, C. Talei Franzesi, M. Ragusi, D. G. Gandola, T. P. Giandola, P. N. Franco, D. Ippolito; Monza/IT
Purpose: This study aimed to determine the diagnostic impact of computed tomography in the evaluation and management of patients with traumatic liver lesions following the American Association for Surgery of Trauma (AAST) scale and its relation to clinical and laboratory data.
Methods or Background: A total of 103 hemodynamically stable patients, with traumatic liver injury, who underwent contrast-enhanced CT scan to assess and quantify liver damage, were enrolled. Imaging data were independently evaluated by a general surgeon and a radiologist (both with more than 15 years of experience). The reviewers first graded liver lesions, according to the AAST scale, blinded to the clinical data. During the second revision session, the reviewers reconsidered the CT findings along with the support of clinical data. The primary study outcome was to determine the patient's management [operative (OM) or not-operative (NOM)] based exclusively on imaging CT findings and by adding laboratory data.
Results or Findings: A good inter-reader agreement was found for AAST grades I, II, III, and V (k= 0.870, k=0.880, k=0.900, and k=1); while in grade IV the agreement was fair (k=0.455). According to the first revision section, the accuracy in determining the management was higher for the radiologist (AUC=0.850, 95% CI 0.770-0.950) than the surgeon (AUC=0.700 95% CI 0.550-0.820), achieving a statistically significant difference (p=0.025). During the second revision session, after correlation with clinical and laboratory data, the overall accuracy between the two readers was statistically comparable (AUC=0.880 and AUC=0.850, p>0.05).
Conclusion: The CT liver damage score, according to the AAST scale, represents a useful and fast approach to correctly address the management of liver trauma patients.
Limitations: This was a retrospective study.
Funding for this study: No funding was received for this study.
Has your study been approved by an ethics committee? Not applicable
Ethics committee - additional information: The study was retrospective.
7 min
Early IVIM-DWI for the prediction of post-pancreatectomy acute pancreatitis
Luca Fortuna, Vicenza / Italy
Author Block: L. Fortuna, L. Costa, B. Maris, G. Zamboni; Verona/IT
Purpose: This study aimed to evaluate early DW-MRI radiological findings and texture analysis parameters that will predict the development of post-pancreatectomy acute pancreatitis (PPAP) in patients undergoing pancreaticoduodenectomy.
Methods or Background: In this IRB-approved prospective study, 65 patients underwent MRI on the third postoperative day after pancreaticoduodenectomy. Scan protocol included standard sequences, post-gadolinium acquisitions, and IVIM-DWI. IVIM DICOM images were analysed with in-house software that produced F, D, and D* maps and allowed us to calculate texture parameters of three different ROIs (stump, tail, entire pancreatic remnant). By retrospectively applying the 2021 ISGPS definition of PPAP, patients were defined as with or without POH/PPAP. Texture parameters and radiological findings were compared between the two groups (Kruskal-Wallis, ANOVA tests).
Results or Findings: The patient population included 33 females and 32 males. 20 patients developed postoperative hyperamylasemia (POH) and 6 of these grade B or C PPAP. Significant differences in texture parameters were identified between the POH/PPAP and the non-POH/PPAP groups for mean ADC (1.33±0.22 vs 1.56±0.28) × (10−3 mm2/s; p=0.006) and D value (0.11±0.14 vs 0.22±0.15; p=0.03), F entropy (4.5±0.10 vs 4.1±0.08 (SE); p=0.004) and D* entropy (2.7±0.73 vs 1.3±0.38 (SE); p=0.01) of ROIs including the pancreatic stump. Similar results were found evaluating ROIs of the tail (mean D, p=0.01; entropy F, p=0.02; entropy D*, p=0.01) and entire pancreatic remnant (mean D, p=0.01; entropy F, p=0.0001; entropy D*, p=0.0001). No macroscopic features consistent with PPAP were identified.
Conclusion: Early postoperative MRI texture analysis of IVIM-derived parameters might predict who will develop PPAP after pancreaticoduodenectomy.
Limitations: The limitations of the study are the limited sample size, the difference in slice thickness between post-contrast T1 images and those in DWI IVIM; the exclusion of patients unable to perform MRI due to early clinical worsening; and POH and PPAP groups union.
Funding for this study: No funding was provided for this study.
Has your study been approved by an ethics committee? Yes
Ethics committee - additional information: This study was approved by the Ethics Committee. The notification can be found under the number 2130 CESC VR-RO.
7 min
Time dependency and risk factors of splanchnic vein thrombosis development in the early phase of acute pancreatitis: a systematic review and meta-analysis
Zsolt Zsolt Borbély Ruben, Budapest / Hungary
Author Block: Z. Z. Borbély Ruben1, B. M. Philip1, E. Á. Szalai1, B. Gellért1, D. Veres Sandor1, B. Teutsch1, B. Erőss1, P. Hegyi1, N. Faluhelyi2; 1Budapest/HU, 2Pécs/HU
Purpose: Splanchnic vein thrombosis (SVT) is a local complication of acute pancreatitis (AP) that may lead to subsequent complications such as portal hypertension, gastrointestinal bleeding, and mesenteric ischemia. This study aimed to analyse the temporal progression and contributing risk factors of SVT occurrence during the early phase of AP.
Methods or Background: We systematically searched medical databases (Embase, MEDLINE via PubMed, Scopus, and CENTRAL) on 27.10.2022. Inclusion criteria were studies using appropriate diagnostic modalities to identify SVT in patients from the early phase of AP. We performed a random-effects meta-analysis, calculated SVT-affected patient proportions with 95% confidence intervals (CI) and conducted subgroup analyses. The protocol was prospectively registered in PROSPERO: CRD42022367578.
Results or Findings: The proportion of patients with SVT within 12 days after symptom onset was 0.13 (CI 0.07-0.23). The occurrence was lowest at 0.06 (CI 0.03-0.1) between 0-3 days after symptom onset and increased fourfold to 0.23 (CI 0.16-0.31) between 3-11 days. The proportion of patients affected on hospital admission was 0.12 (CI 0.02-0.49), and it was 0.17 (CI 0.03-0.58) 1-5 days after admission. Alcoholic aetiology (0.31, CI 0.13-0.58) and pancreatic necrosis (0.55, CI 0.29-0.78, necrosis above 30%) correlated with increased SVT prevalence.
Conclusion: The risk of developing SVT is significant in AP, affecting up to a quarter of patients. The risk of occurrence increases with time in the early stages of AP. Alcoholic aetiology and pancreatic necrosis elevate the risk for SVT in AP. Our findings highlight the need for anticoagulation therapy and advanced imaging (CT, MRI) to become a routine component of AP therapy.
Limitations: The limitations were the lack of individual patient data and aggregate data from published studies limited our ability to control for potential confounders and explore effect modifiers beyond subgroup analyses.
Funding for this study: The research was supported by the Hungarian Ministry of Innovation and Technology, National Research, Development and Innovation Fund (TKP2021-EGA-23 to PH), Translational Neuroscience National Laboratory program (RRF-2.3.1-21-2022-00011 to PH), a project grant (K131996 to PH) and the Translational Medicine Foundation. Funding for Brigitta Teutsch was provided by the ÚNKP-22-3 New National Excellence Program of the Ministry for Innovation and Technology from the source of the National Research, Development and Innovation Fund (to BT - ÚNKP-22-3-I-PTE-1693). The funders did not affect the concept, data collection, analysis, or writing of the manuscript.
Has your study been approved by an ethics committee? Not applicable
Ethics committee - additional information: No ethical approval was required for this systematic review with meta-analysis, as all data were already published in peer-reviewed journals. No patients were directly involved in the design, conduct, or interpretation of our study.
7 min
Extracellular volume fraction derived from dual-energy CT: a potential predictor for postpancreatectomy acute pancreatitis after pancreatoduodenectomy
Xiaohan Bai, Nanjing / China
Author Block: X. Bai, J. Yin, H. Shi, K. Jiang, Q. Xu; Nanjing/CN
Purpose: This study aimed to investigate the value of extracellular volume (ECV) fraction and fat fraction (FF) derived from dual-energy CT (DECT) for predicting postpancreatectomy acute pancreatitis (PPAP) after pancreatoduodenectomy (PD).
Methods or Background: This retrospective study included patients who underwent DECT and PD between April 2022 and September 2022. PPAP was determined according to the International Study Group for Pancreatic Surgery (ISGPS) definition. Iodine concentration (IC) and fat fraction of the pancreatic parenchyma were measured on preoperative DECT. The ECV fraction was calculated from iodine map images of the equilibrium phase. The independent predictors for PPAP were assessed by univariate and multivariate logistic regression analyses and receiver operating characteristic (ROC) curve analyses.
Results or Findings: 69 patients were retrospectively enrolled (median age, 60 years; interquartile range, 55-70 years; 47 men). Of these, nine patients (13.0%) developed PPAP. These patients had lower portal venous phase IC, equilibrium phase IC, FF and ECV fraction, compared with patients without PPAP. After multivariate analysis, ECV fraction was independently associated with PPAP (odd ratio [OR], 0.87; 95% confidence interval [CI]: 0.79, 0.96; p<0.001), with an area under the curve (AUC) of 0.839 (sensitivity 100.0%, specificity 58.3%).
Conclusion: A lower ECV fraction is independently associated with the occurrence of PPAP. ECV fraction may serve as a potential predictor for PPAP.
Limitations: No limitations were identified.
Funding for this study: No funding was received for this study.
Has your study been approved by an ethics committee? Not applicable
Ethics committee - additional information: No information provided by the submitter.

This session will not be streamed, nor will it be available on-demand!