RPS 901 - Advances in small bowel imaging: from ischaemia to perforation

Author Block: S. Thavarajah¹, H. Garnier¹, S. Vilain¹, M. Ronot¹, L. Garzelli²; ¹Clichy/FR, ²Paris/FR
Purpose: To evaluate the prevalence, imaging features, and prognostic significance of bowel hypoenhancement on CT in arterial occlusive acute mesenteric ischaemia (AOAMI).
Methods or Background: Retrospective, observational, single-centre study of 220 patients referred to our intestinal stroke unit between 2006 and 2023. All patients with AOAMI and available portal-venous phase abdominal CT were reviewed. Clinical, biological, treatment, and outcome data were retrieved from a prospective database. The primary objective was prevalence and imaging description of bowel wall hypoenhancement; the secondary objective was its association with bowel resection-free survival and other prognostic factors.
Results or Findings: Among 220 patients (median age 68 years; 55% men), bowel hypoenhancement was present in 127 (57%), predominantly in the ileum (95%). It was was more frequent in embolic than atherosclerotic occlusion (61% vs 38%) and was associated with decreased venous outflow in 58%. Compared with patients without bowel hypoenhancement, these patients had higher lactate (2.8 vs 1.7 mmol/L, p<0.001), more frequent leukocytosis >15G/L (63% vs 40%, p=0.001), and a greater prevalence of portomesenteric gas (14% vs 1%, p<0.001). Resection was more frequent (72% vs 31%, p<0.001) with longer segments removed (154 vs 85 cm, p=0.007), and patients more often required home parenteral nutrition (17% vs 5%, p=0.018). Resection-free survival was significantly lower in patients with hypoenhancement (log-rank p<0.001).
Conclusion: Bowel hypoenhancement on CT is frequent in AOAMI and constitutes a marker of disease severity. Its early recognition may help identify high-risk patients, and anticipate adverse outcomes.
Limitations: Limitations include retrospective, single-centre design, possible selection bias, and reduced reproducibility as hypoenhancement was assessed by a single reader.
Funding for this study: None
Has your study been approved by an ethics committee? Not applicable
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Author Block: S. Vilain¹, H. Garnier¹, M. Dioguardi Burgio¹, J. Gregory¹, M. Ronot¹, L. Garzelli²; ¹Clichy/FR, ²Paris/FR
Purpose: The prognostic impact of superior mesenteric artery (SMA) lesion type and distribution on management and outcomes in acute occlusive arterial mesenteric ischaemia (AOAMI) remains uncertain.
Methods or Background: Retrospective single-centre study including patients treated for AOAMI between 2016 and 2024 in our intestinal stroke centre unit. Patients with incomplete SMA occlusion were excluded. SMA lesions were classified according to Tual et al. as proximal (S1), median (S2), or distal (S3), and graded as stenosis, occlusion with downstream patency, or occlusion without downstream patency. Lesion burden was defined as the number of occluded segments. Outcomes included revascularisation strategy, gastrointestinal morbidity (short bowel syndrome [SBS], home parenteral nutrition [HPN]), and mortality.
Results or Findings: One hundred forty-two patients were included (mean age 67 years, 60% men); 68% had embolic and 30% atherothrombotic AOAMI. Median lactate was 2.5 mmol/L; Revascularisation was attempted in 86%, and 85 patients required bowel resection. Overall mortality was 39%. At follow-up, 18% were alive without gastrointestinal sequelae, 22% had SBS, and 14% required HPN. The dominant lesions were most frequently S2 (48%), followed by S1 (37%) and S3 (15%); mean length was 51 mm, with 36% >50 mm. Occlusion without downstream patency occurred in 47%, and 23% involved >2 territories without patency. Lesion distribution influenced endovascular strategy: stenting mainly for S1 with downstream patency, thrombolysis for S3, and thrombectomy for S2–S3. Lesion burden correlated with gastrointestinal morbidity but not mortality. Mortality was significantly associated with inferior mesenteric artery occlusion and splanchnic arterial calcifications (p=0.038 and <0.01).
Conclusion: SMA lesion type and distribution determine endovascular strategy in AOAMI, while lesion burden predicts gastrointestinal morbidity.
Limitations: Retrospective design and potential selection bias
Funding for this study: None
Has your study been approved by an ethics committee? Not applicable
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Author Block: H. Garnier¹, S. Thavarajah¹, S. Vilain¹, M. Ronot¹, L. Garzelli²; ¹Clichy/FR, ²Paris/FR
Purpose: Outcomes of arterial occlusive acute mesenteric ischaemia (AOAMI) are usually reported as short-term survival, which underestimates long-term morbidity. We aimed to propose a morbidity-mortality scale to provide a more comprehensive outcome measure for clinical trials in patients with AOAMI.
Methods or Background: Retrospective, single-centre study including patients admitted for AOAMI (2016–2023). Clinical, biological, imaging, treatment and outcomes data were analysed. A four-level morbidity-mortality scale was developed according to post-AMI status: 0 = bowel preservation, 1 = bowel resection, 2 = intestinal failure and 3 = death. The primary outcome was the distribution of the scale at 1, 3, 6 or 12 months.
Results or Findings: A total of 256 patients were included (median age: 68; 44% female). Overall, 149 (58%) underwent bowel resection and 73 (29%) developed short bowel syndrome during follow-up. Thirty-five patients (14%) required long-term parenteral nutrition, including 16 (6%) with >4 infusions per week. At last follow-up, one-third of patients (33%) had a digestive stoma. Scale distribution was as follows: scale 0 (bowel preservation) stable at 32%, 30%, 30% 30% at 1, 3, 6 and 12 months ; scale 1 (resection) stable at 24%, 24%, 25% 24% at 1, 3, 6 and 12 months ; scale 2 (intestinal failure) decreased from 25% to 15% from 1 to 12 months ; scale 3 (death) increased from 19% to 31% from 1 to 12 months.
Conclusion: This new morbidity-mortality scale captures both survival and functional outcomes, providing a comprehensive measure of disease burden in AOAMI. It could serve as a novel endpoint in future therapeutic trials.
Limitations: Limitations include the retrospective, single-centre design, which may entail missing data, selection bias, and limited generalisability.
Funding for this study: None
Has your study been approved by an ethics committee? Not applicable
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Author Block: J. André¹, T. Pesce², C. Iosif², M. Ronot³, M. Zappa¹, L. Garzelli³; ¹Cayenne/GF, ²Fort de France/FR, ³Paris/FR
Purpose: Normal CT dimensions of the small bowel are not established, although calibre and wall thickness are routinely measured in ischaemic, inflammatory, and obstructive diseases. This study aimed to define normative values in adults without intestinal abnormalities.
Methods or Background: In this prospective bicentric study, adults from French Guiana and Martinique (french overseas territories) undergoing portal venous phase abdominal CT between May and October 2023 were screened. Patients with abdominal abnormalities or previous surgery were excluded. Calibre and wall thickness were measured at six arterial landmarks (proximal, mid, and distal jejunum and ileum). Associations with age, sex, and geographic origin were analysed. Inter- and intra-observer reproducibility was assessed in 10% of cases using intraclass correlation coefficients (ICCs).
Results or Findings: Among 2,336 screened patients, 502 were included (mean age 52 years; 56% women; French Guiana n=249; Martinique n=253). Mean jejunal calibre and thickness were 24.6 mm (± 2.0) and 2.6 mm (± 0.4), compared with 19.8 mm (± 3.0) and 1.3 (± 0.2) mm in the ileum. Jejunal values were significantly greater than ileal ones (p<0.01). Calibre increased with age, whereas thickness decreased (both p<0.01; r=0.70 and r=−0.64). Neither sex (calibre p=0.36; thickness p=0.63) nor geographic origin (calibre p=0.42; thickness p=0.54) significantly influenced measurements. Reproducibility was substantial, with ICCs of 0.78 (intra) and 0.73 (inter) for calibre, and 0.70 (intra) and 0.72 (inter) for wall thickness.
Conclusion: This large bicentric study provides reference CT values for small bowel calibre and wall thickness by segment, showing a progressive reduction from proximal jejunum to distal ileum with variations across age. These benchmarks may enhance standardisation for clinical diagnosis and research.
Limitations: Limitations are underrepresentation of non-American populations, absence of anthropometric data, and potential bias from trauma cases.
Funding for this study: None
Has your study been approved by an ethics committee? Not applicable
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Author Block: G. Shaden, N. Lev-Cohain; Jerusalem/IL
Purpose: Magnetic resonance (MR) imaging is considered a second-line technique after transvaginal ultrasonography (TVUS) in suspected endometriosis. Updated MRI indications have recently been defined by the ESUR consensus. This study aimed to evaluate, in our institutional cohort, which patients benefit from MRI beyond TVUS, and to assess adherence to ESUR indications in routine practice.
Methods or Background: We retrospectively reviewed 103 women with suspected or confirmed endometriosis who underwent both TVUS and pelvic MRI between 2020 and 2025 at a tertiary endometriosis centre. All TVUS were performed by a single expert gynaecological sonographer, and all MRIs interpreted by the same senior radiologist specialising in endometriosis imaging. Findings were compared across compartments (anterior, middle, posterior, and extra-pelvic). Interpretations were categorised as: (1) normal TVUS with abnormal MRI; or (2) abnormal TVUS, with assessment of MRI’s incremental diagnostic contribution.
Results or Findings: Among 23% of patients (24/103) with normal TVUS, MRI revealed deep endometriosis in 58% (14/24), confirming its added value in symptomatic women with negative ultrasound. When both modalities demonstrated endometriosis, MRI consistently contributed further diagnostic information. The clearest difference was in bowel assessment: MRI detected bowel involvement in 55% (28/51) of patients missed by TVUS, and in 29% (15/51) of those with TVUS-suspected bowel disease, MRI more accurately defined depth and extent of infiltration.
Conclusion: MRI is essential in symptomatic patients with negative TVUS, in line with ESUR consensus. In addition, when TVUS suggests deep endometriotic plaques—particularly in locations where ultrasound is less sensitive—MRI should be performed, as it provides superior delineation of disease extent and involvement.
Limitations: Retrospective single-centre design.
Variable TVUS–MRI intervals (median 35 days; 25% >6 months) may have influenced discrepancies.
Funding for this study: None.
Has your study been approved by an ethics committee? Not applicable
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Author Block: X. Liu, R. CHEN; Zhuhai, Guangdong, China./CN
Purpose: The selection of surgical approach and incision for gastrointestinal perforation depends on factors such as the location and etiology of the perforation. Accurate preoperative localization and etiological assessment are critical for optimal treatment planning. Currently, computed tomography (CT) is the unique preoperative method for localization; however, its accuracy is limited and it’s time-consuming. Existing studies focus on specific imaging signs and adopt the mechanical anatomical grouping based on the sequence of gastrointestinal tract, neglecting the hydrodynamic characteristics of the peritoneal compartments. This study intends to group based on gastrointestinal-peritoneal relationships to evaluate the distribution pattern of free gas and characteristic CT signs of perforation in each group, in order to improve the preoperative localization accuracy and shorten the diagnostic time.
Methods or Background: In a retrospective study, 250 patients with surgically confirmed gastrointestinal perforations were classified into three anatomical groups: intraperitoneal, interperitoneal, and extraperitoneal. CT studies were reviewed using tailored window settings and multiplanar reconstructions to assess the distribution of free gas and specific imaging signs. Comparative statistical analysis was performed.
Results or Findings: Free gas distribution demonstrated strong anatomical dependence: intraperitoneal perforations primarily involved the supracolic compartment; interperitoneal perforations localized to the mesenteric root space; and extraperitoneal perforations were characterized by retroperitoneal gas. The most prevalent ancillary signs were ascites, tiny intra-abdominal gas bubbles, and fat stranding.
Conclusion: Leveraging anatomical and radiopathological correlations, this study proposes a novel diagnostic pathway: “pneumoperitoneum distribution → anatomical grouping → targeted lesion identification.” This systematic approach facilitates efficient and accurate perforation localization by utilizing gas distribution patterns to prioritize anatomical segments. A stepwise evaluation sequence—beginning with the retroperitoneum, followed by the mesenteric sinuses, and finally the supracolic space—is recommended, augmented by attention to key CT signs and optimized windowing.
Limitations: No
Funding for this study: The Clinical Research Promotion Project of Zhuhai People's Hospital(Grant No. 2023LCTS-03)
Has your study been approved by an ethics committee? Yes
Ethics committee - additional information: No

Author Block: U. Dutta, N. Chantima, I. Miglior, J. Chmelo, J. Brown, A. Phillips; Newcastle upon Tyne/UK
Purpose: To audit gastrografin use and timing of follow-up abdominal X-rays (AXRs) in adhesive small bowel obstruction (ASBO) management at a tertiary-care centre.
Methods or Background: The 2017 Bologna guidelines recommend water-soluble contrast in the conservative management of ASBO. Consensus favours obtaining a follow-up AXR at least 6 hours post-gastrografin administration to allow adequate bowel transit time.

We conducted a retrospective audit over a 6-month period of all acute surgical admissions with uncomplicated ASBO confirmed on computed tomography (CT). We examined gastrografin prescription, administration timing, and follow-up AXR intervals. Following educational interventions (departmental posters and teaching sessions), we re-audited practice between April-August 2025.
Results or Findings: Of 74 ASBO patients, 57 received gastrografin with follow-up AXRs. Nine patients (18%) were scanned <6 hours post-administration, with mean prescription-to-AXR time of 6.6 ± 2.0 hours and administration-to-AXR time of 4.9 ± 1.0 hours. Successful transit to colon was seen in approximately two-third of cases. Ten patients underwent multiple AXRs; eight received repeat gastrografin.
Root-cause analysis revealed that in 48/57 cases (84%), follow-up AXRs were requested at prescription rather than administration, failing to account for the mean 1.7 ± 1.0 hour prescription-administration delay. Re-audit demonstrated significant improvements better adherence to current recommendations: only 3/45 patients (7%) scanned <6 hours, with mean AXR timing improved to 7.0 ± 1.5 hours.
Conclusion: Enhanced communication between clinicians, nurses, and radiographers optimizes AXR timing in ASBO management.
Limitations: The paucity of national guidelines and indeed a local protocol on the use of gastrografin is a key limitation towards sustained improvement.
Funding for this study: Not applicable.
Has your study been approved by an ethics committee? Not applicable
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