CT data analysis of catheter morphology and displacement in peritoneal dialysis: an exploratory study.

Purpose: Catheter displacement is a common complication of peritoneal dialysis. The aim of this study was to explore the correlation between catheter morphology and displacement by analyzing CT data, providing a scientific basis for optimizing catheter morphology within abdominal wall layers.

Methods: We retrospectively analyzed the clinical data of 94 patients. The parameters for analyzing catheter morphology were defined based on six key points identified from CT images. The covariates considered in the analysis included demographics, primary disease, body size, peritoneal dialysis method, and total weekly urea clearance index.

Results: During a mean follow-up period of 1056 ± 480 days, only the angle of the intramuscular part (IM angle) of the catheter significantly correlated with the time to first catheter displacement according to the multivariate analysis (hazard ratio [HR]: 1.039, 95% confidence interval [CI] 1.02-1.058, $p<$ 0.01). When the cut-off value of IM angle was 39.4 ${}^{\circ }$ , the area under receiver-operating characteristic (ROC) curve for predicting catheter displacement was 0.791 (95% CI 0.701-0.881, $p<$ 0.01), with a sensitivity and specificity of 82.9% and 66.0%, respectively. Kaplan-Meier survival curves showed that the catheter survival rate was significantly higher in the group with an IM angle < 39.4 ${}^{\circ }$ than in the group with an IM angle > 39.4 ${}^{\circ }$ (log-rank ${\chi }^2$ =19.479, $p<$ 0.01). None of the catheter morphology parameters were significantly correlated with technique survival in the multivariate analysis.

Conclusion: There is a correlation between catheter morphology and catheter displacement. An IM angle > 39.4 ${}^{\circ }$ is an independent risk factor for catheter displacement, while the position and angle of the subcutaneous part are not correlated with catheter displacement.