Diagnosis Of Gastrointestinal Tract Perforation On Computed Tomography.

Tatjana Malevska; Aelita Zvigure Rīga Stradiņš University, Riga East University Hospital, Latvia.

Key wordsComputed tomography; Perforation; Gastrointestinal tract.

ConclusionsCT of the abdomen can be a valuable investigative tool in detecting and localizing a GI tract perforation site at any location what is important for surgical planning. Basing on the surgery results calculated CT sensitivity is 94.9% and specificity -70%. Gastrointestinal perforation does not occur equally in all gastrointestinal sections – more frequently perforates stomach and sigma.Gastrointestinal perforation on CT images has its own specific characteristics which do not differ from a perforation location, but the detection frequency is not the same in different localizations.The most frequent GI perforation signs on the CT ir free air, its detected in 99% of perforation cases and in 80% of cases with microperforation.

ObjectiveGastrointestinal (GI) tract perforation is an emergent condition that requires prompt surgery. Diagnosis largely depends on imaging examinations, and correct diagnosis of the presence, level, and cause of perforation is essential for appropriate management and surgical planning. Plain radiography remains the first imaging study and may be followed by intraluminal contrast examination; however, the high clinical efficacy of computed tomographic (CT) examination in this field has been well recognized. Extraluminal air that is too small to be detected by conventional radiography can be demonstrated by CT. Indirect findings of bowel perforation such as phlegmon, abscess, peritoneal fluid, or an extraluminal foreign body can also be demonstrated. Gastrointestinal mural pathology and associated adjacent inflammation are precisely assessed with thin-section images and multiplanar reformations that aid in the assessment of the site and cause of perforation.

MethodsIn the study were included 138 patients who were hospitalized in Riga East University Hospital Clinic of Emergency Medicine in period of 01.09.2014 – 05.11.2015 (64 men and 74 women, in age 23 to 94, average age – 62 years). In research were included patients who undergo CT because of suspected GI perforation and patients with GI perforation diagnosed by CT. CT findings were analyzed in all cases, US, X-ray or surgery findings were analyzed if they were done. Evaluating findings of perforation by CT, depending on the perforation localization, patients were divided into three groups:

1) stomach and duodenum; 2) small intestine; 3) large intestine and appendix.

Among 138 cases, were detected 104 perforations, six microperforations of them and in 12 cases perforation diagnosis was questionable.

ResultsUsing CT in 110 (79.7%) cases has been detected extraluminal air, in 99 cases (71.7%) free liquid. Of 98 people whom perforation was confirmed, free air on CT was found in 97 cases (98.9%), 80 people had free liquid (81.6%). Most common causes of perforation: ulcer perforation - 38 cases (32.48%), diverticular perforations - 27 cases (23.08%) and tumor-induced perforations -17 cases (14.53%).Most affected GI tract part is the stomach - 28 cases (23.93%); second is S-shaped intestine - 25 cases (21.37%). After data processing, was concluded that gastrointestinal perforation findings depend on the perforation location. In case of gastric and duodenal perforation is high incidence extraluminal air and free fluid - 87% and 89% respectively. Small bowel perforation air and liquid were found less frequently - 64.7% air and 52.9% liquid. Colon perforation - air 80.3%, the liquid - 62.2%.The surgery was applied to 88 patients (63%), perforation was confirmed in 75 cases (85.2%). Basing on the surgery results calculated CT sensitivity is 94.9% and specificity -70%..

32.48%

23.08%

14.53%

9.40%

8.55%

5.13%2.56%

0.85%0.85% 0.85%

Causes of gastrointestinal perforation.

Peptic Ulcer DiseaseDiverticulitis

Cancer

Appendicitis

Ischemia

Unknown

Trauma

Pancreatitis

Adhesive DiseaseForeign body

4.27%

1.71%

9.40%

2.56%

21.37%

12.82%

10.26%

11.97%

23.93%

0% 5% 10% 15% 20% 25%

Unknown

Extensive bowel damage

Appendix

Rectum

Sigma

Colon

Small intestine

Duodenum

Gaster

Localization of perforation.

9.09%50.00%

83.33%98.98%

40.91%75.00%

66.67%81.63%

0% 20% 40% 60% 80% 100%

No perforatoinQuestionable

MicroperforationPerforation

CT findings in different CT conclusion.

Free liquid Free Air

87.00%64.70%

80.30%89.10%52.90% 65.20%

0.00%

50.00%

100.00%

Localization #1 Localization #2 Localization #3

CT findings in different localizations.

Free Air Free Liquid