Diffusion-weighted magnetic resonance for assessing fibrosis in Crohn's disease.

BACKGROUND: Intestinal fibrosis is a key feature of Crohn's Disease lesions, and mucosal biopsies do not exactly represent transmural damage. Magnetic resonance enterography (MRE) allows for a panoramic study of the bowel loops. Diffusion-weighted imaging (DWI) through the restriction of the apparent diffusion coefficient (ADC) allows for an accurate evaluation of disease activity in Crohn's Disease patients avoiding contrast agents. The aim of this study was to investigate whether DWI sequences were able to identify intestinal fibrosis in candidates for surgery, using histopathology as the gold standard. MATERIALS AND METHODS: Thirty Crohn's Disease patients undergoing surgery for stricturing ileo-colonic disease were consecutively enrolled from October 2010 to November 2015. All patients underwent MRE with DWI before surgery. Radiological parameters were calculated in the stenotic segment and in the ileum proximal to the stenosis. The histopathological examination was performed using a histological score for fibrosis and inflammation. RESULTS: ADC value correlated with the fibrosis score (r = -0.648; p < 0.0001), inflammation score (r = -0.763; p < 0.0001) and percentage of gain (r = -0.687; p < 0.0001). A correlation emerged between wall thickness and fibrosis score (r = 0.671; p < 0.0001). The threshold of wall thickness for fibrosis was > 6.3 mm (AUC 0.89, specificity 100% and sensitivity 69.23%). The cut-off of ADC value for fibrosis was < 1.1 × 10-3 mm2 s-1 with a sensitivity of 72% and specificity of 94% (AUC = 0.83). CONCLUSIONS: The DWI sequence with ADC value could be useful to identify fibrosis in the intestinal wall of Crohn's Disease patients.

Facial asymmetry quantitative evaluation in oculoauriculovertebral spectrum.

OBJECTIVES: Facial asymmetries in oculoauriculovertebral spectrum (OAVS) patients might require surgical corrections that are mostly based on qualitative approach and surgeon's experience. The present study aimed to develop a quantitative 3D CT imaging-based procedure suitable for maxillo-facial surgery planning in OAVS patients. MATERIALS AND METHODS: Thirteen OAVS patients (mean age 3.5 ± 4.0 years; range 0.2-14.2, 6 females) and 13 controls (mean age 7.1 ± 5.3 years; range 0.6-15.7, 5 females) who underwent head CT examination were retrospectively enrolled. Eight bilateral anatomical facial landmarks were defined on 3D CT images (porion, orbitale, most anterior point of frontozygomatic suture, most superior point of temporozygomatic suture, most posterior-lateral point of the maxilla, gonion, condylion, mental foramen) and distance from orthogonal planes (in millimeters) was used to evaluate the asymmetry on each axis and to calculate a global asymmetry index of each anatomical landmark. Mean asymmetry values and relative confidence intervals were obtained from the control group. RESULTS: OAVS patients showed 2.5 ± 1.8 landmarks above the confidence interval while considering the global asymmetry values; 12 patients (92%) showed at least one pathologically asymmetric landmark. Considering each axis, the mean number of pathologically asymmetric landmarks increased to 5.5 ± 2.6 (p = 0.002) and all patients presented at least one significant landmark asymmetry. CONCLUSIONS: Modern CT-based 3D reconstructions allow accurate assessment of facial bone asymmetries in patients affected by OAVS. The evaluation as a global score and in different orthogonal axes provides precise quantitative data suitable for maxillo-facial surgical planning. CLINICAL RELEVANCE: CT-based 3D reconstruction might allow a quantitative approach for planning and following-up maxillo-facial surgery in OAVS patients.