Evidences supporting the vascular etiology of post-double balloon enteroscopy pancreatitis: Study in porcine model

Abstract

Double balloon enteroscopy (DBE) is an endoscopic technique broadly used to diagnose and treat small bowel diseases. Among the associated complications of the oral DBE, post-procedure pancreatitis has taken the most attention due to its gravity and the thought that it might be associated to the technique itself and anatomical features of the pancreas. However, as the etiology has not been clarified yet, this paper aims to review the published literature and adds new results from a porcine animal model. Biochemical markers, histological sections and the vascular perfusion of the pancreas were monitored in the pig during DBE practice. A reduced perfusion of the pancreas and bowel, the presence of defined hypoxic areas and disseminated necrotic zones were found in the pancreatic tissue of pigs. All these evidences contribute to support a vascular distress as the most likely etiology of the post-DBE pancreatitis.

Keywords: Animal model; Double balloon enteroscopy; Pancreas; Pancreatitis; Pig.

Figure 1

Light microscopy image of the porcine pancreas after double-balloon enteroscopy showing located ischemic necrosis in pancreatic interlobular tissue.

Figure 2

Pancreas immunohistochemistry. A: Expression of the VEGF in a normal parenchyma; B: Pancreatic acini with normal structure and nuclei, which express VEGF. In upper right corner a ischemic zone where less VEGF expression is shown, the pancreatic acini structure has been lost and nuclei are pyknotic. VEGF: Vascular endothelial growth factor.

Figure 3

Pancreas immunohistochemistry. A: Expression of the pimonidazole hydrochloride (Hypoxyprobe^®) presence of focal areas positively stained; B: Serial section stained with hematoxyline-eosine.

Figure 4

Selective angiogram of the cranial mesenteric artery. T₀: Before the DBE; T₁: With the endoscope inserted at maximum during DBE. Red line shows the aorta topography. DBE: Double balloon enteroscopy.

Figure 5

Computed tomography angiogram (A) with vascular 3D reconstruction to monitor his individual vascular anatomy (1) abdominal aorta; (2) cranial mesenteric artery; (3) celiac artery; (4) splenic artery; (5) hepatic artery; and (6) major pancreatic artery. B: Super-selective angiography of the major pancreatic artery (arrow) with the endoscope inserted at maximum during DBE. The nuclear dye Hoechst (Bizbenzimida H 33258 fluorochrome) is injected through that vessel to allow its contact with the cells in the tail of the pancreas. DBE: Double balloon enteroscopy.

Figure 6

Fluorescence microscopy image of cryosections from left lobe of the pancreas showing distribution of endocrine and exocrine cells with nuclei stained in disto-medial (A-C) and proximo-lateral (D-F) portions. A and D: Serial sections stained with hematoxyline-eosine; B-E: Serial sections stained with the nuclear marker TO-PRO^®3 iodide; C and F: Serial sections showing the location the nuclear dye Hoechst (Bizbenzimida H 33258 fluorochrome).