The establishment of a regression model from four modes of ultrasound to predict the activity of Crohn's disease

Abstract

To establish a multi-parametric regression model from four modes of ultrasound to predict the activity of Crohn's disease (CD) noninvasively. Score of 150 of the Crohn's Disease Activity Index (CDAI) was taken as the cut-off value to divide the involved bowel segments of 51 patients into the active and inactive group. Eleven parameters from four modes of ultrasound (B-mode ultrasonography, color Doppler flow imaging, contrast-enhanced ultrasonography and shear wave elastography) were compared between the two groups to investigate the relationship between multimodal ultrasonic features and CD activity. P < 0.05 was considered statistically significant. Parameters with AUC larger than 0.5 was selected to establish the prediction model of CDAI. Totally seven ultrasound parameters (bowel wall thickness, mesenteric fat thickness, peristalsis, texture of enhancement, Limberg grade, bowel wall perforation and bowel wall stratification) were significantly different between active and inactive group. A regression model was established based on the seven parameters as followed: CDAI = 211.325 + 3.186BWT - 53.003BWS + 6.280BWP + 0.392MFT + 22.239PS + 79.012LG + 72.793TE. (R² = 0.72, P = 0.037). The multimodal ultrasound parametric regression model was designed to predict CDAI score invasively. The model has the potential to provide an alternative method for quantifying the CD activity.

Figure 1

Examples of ultrasonic findings. Male, 18y, recurrent gastrointestinal bleeding for 1 year, CDAI: 336. (a) White arrow indicates thickening of the colon wall. (b) White arrows indicate mesenteric fat thickening. A lymph node can be detected in the thickened mesenteric fat. (c) White arrow indicates mesenteric lymphadenopathy. (d) The vascularization in the colon wall was scored to be Limberg II. (e) White arrow indicates that the anterior wall of the colon is soft, and the shear wave elastography of the anterior wall is homogeneous blue with a mean SWV of 2.1 m/s. Figure 1f. White arrow indicates a transmural homogeneous enhancement (TE homogeneous), and stratification of the intestinal wall still remains (SE presence).