Functional versus radiological assessment of chronic intestinal ischaemia

Abstract

The diagnosis chronic intestinal ischaemia (CII) is based on the clinical symptoms postprandial pain and weight loss combined with abnormal findings during angiography. Despite the well-known poor correlation between symptoms and morphology, physiological tests are rarely performed. It is possible to measure the total splanchnic blood flow (SBF) before and after a test meal, and the results supply additional information to the morphologic investigations. To date, no papers have addressed the impact of morphologic changes of the mesenteric arteries on the SBF. Forty-six consecutive patients suspected of CII were investigated. The routine investigation included angiography and measurements of the SBF before and after a test meal. Measurements of the total SBF were performed using the 'Fick principle'. (99m)Technetium-labelled Mebrofenin was used as a tracer. Digital subtraction angiography was performed. Agreement between SBF and angiography was found in 44 of 46 patients. Mean baseline SBF for all patients was 985 ml/min, total range (525-1932) and within the reported normal range. The mean postprandial increase in SBF was 480 mL min(-1) (-130 to 1353), thus 36 patients were categorized as normal by both angiography and SBF, eight patients were abnormal by both methods and two patients had abnormal SBF but normal angiography. In this cohort, SBF detects CII with sensitivity of 1.0, and specificity of 0.95. SBF supplies additional information in patients with convincing symptoms and normal angiography. In these patients, the affection of the intestinal arteries may be too distant or too subtle to be visualized on angiography.