CT evaluation of gastrointestinal system perforations: A retrospective comparative analysis between retroperitoneal and intraperitoneal perforation sites.

Background: Correct identification of the etiology and anatomical location of perforations is paramount for ensuring optimal therapeutic intervention and surgical planning in cases of gastrointestinal tract perforation.

Purpose: This study aimed to retrospectively evaluate the distinctive multidetector computed tomography (MDCT) findings of intraperitoneal and retro-/extraperitoneal perforation by comparing the locations of free air in the abdomen and other imaging findings.

Material and methods: A total of 226 patients with acute abdominal pain who visited the emergency department and underwent contrast-enhanced CT between January 2016 and November 2023 were included. The study consisted of 146 male and 80 female patients with a median age of 53.5 years. Surgical findings determined the site of perforation in all cases. Two radiologists evaluated the CT images in a consensus blind to operative findings, assessing the presence of specific air distributions and strong predictors of gastrointestinal tract perforation.

Results: The study included 192 intraperitoneal and 34 retro-/extraperitoneal perforation cases. Subphrenic free air and periportal free air were statistically significant in differentiating intraperitoneal gastrointestinal tract perforation among specific air distributions. Conversely, the presence of free air in the minor pelvis, right lower quadrant, left lower quadrant, and retroperitoneum was significant in differentiating retro-/extraperitoneal gastrointestinal tract perforation. Among strong imaging predictors, only ascites was statistically significant in differentiating intraperitoneal from retro-/extraperitoneal perforations.

Conclusion: Findings from MDCT may serve as predictive indicators for the precise localization of gastrointestinal tract perforations, which is crucial for appropriate management and surgical planning.