P165. Small intestine contrast ultrasonography (SICUS) for the assessment of intestinal strictures in Crohn's disease: A prospective comparative study vs pathological, histological, morphometric findings
N. Pallotta1, A. Vetuschi2, G. Vincoli1, R. Sferra2, S. Pompili2, C. Montesani3, P. Chirletti4, E. Gaudio5, E.S. Corazziari1
1Sapienza University of Rome, Medicina Interna e Specialita' Mediche, Italy; 2University of L'Aquila, Medicina Sperimentale, Italy; 3Sapienza University, IV Clinica Chirurgica, Rome, Italy; 4Sapienza University of Rome, Chirurgia F. Durante, Italy; 5Sapienza University of Rome, Scienze Anatomiche, Istologiche, Medico Legali e dell'Apparato Locomotore, Italy
Background: In Crohn's disease (CD) patients, small intestine contrast ultrasonography (SICUS) accurately detects small bowel lesions and intra-abdominal CD complications . In addition it visualizes the multilayered structure of the intestinal wall. Aim: To assess with SICUS morphological characteristics of small bowel wall strictures compared to surgical, pathological, histological, morphometric analyses in CD patients.
Methods: Forty-nine CD patients (21 F, mean age 37.7 yrs; range 1278 yrs) submitted to resective bowel surgery were included. The accuracy of SICUS to assess pre-operatively length of strictures was evaluated by paired Student's t‑Test. In 6 patients SICUS measurements of the multilayered structure of bowel wall were compared to histological (H&H, Masson trichromic stain, Pas) and morphometric analyses.
Results: Compared to surgery SICUS identified at least 1 stricture in 39/40 and excluded it in 9/9 (97.5% sensitivity, 100% specificity, k = 0.93); two or more strictures in 9/12 (75% sensitivity, 100% specificity, k = 0.78). The agreement by k‑statistics between SICUS and surgery in identifying proximal and distal small bowel site of stricture was 1 and 0.92, respectively. The extension of strictures was 6.8±5.4 cm at surgery, 6.6±5.4 cm at SICUS (n.s). Compared to the non-stenotic segments adjacent to the strictures SICUS, histological and morphometrical measurements revealed an increased thickness of the intestinal wall with mucosa, submucosa and muscle layers showing similar increased thickness due to fibrosis equally represented in the three layers. The proportion of mucosa, submucosa and muscle layers was not different between non-stenotic and stenotic segments (at histology 15.8% vs 12%, 37.4% vs 33%. 41% vs 42%, at SICUS 21.6% vs 21.7% 29.8% vs 25%, 20.5% vs 27.6%).
Conclusions: These data indicate that: (1) SICUS is an accurate method to assess small bowel strictures in CD patients; (2) at the level of stricture the wall thickness is increased being unchanged the relative thickness of the mucosa, submucosa and muscle layers for the even deposit of fibrosis in each of them.
1. Pallotta N et al IBD 2011.