Dynamic functional examination of the peritoneal dialysis catheter using color Doppler ultrasound. In vitro technical evaluation and in vivo application.

BACKGROUND: Peritoneal dialysis catheter malfunction compromises dialysis adequacy. Standard imaging methods in the case of peritoneal catheter malfunction include abdominal X-ray, fluoroscopic catheter peritoneography, and computed tomography. Ultrasound has only recently been utilized to evaluate the intraperitoneal part of the catheter. In clinical routine, catheter function is assessed by the time needed to fill or drain a defined quantity of peritoneal dialysis fluid. Visual functional testing of the catheter can be performed by fluoroscopy or by contrast-enhanced ultrasound. We developed and tested a color Doppler ultrasound technique for dynamic imaging of the peritoneal catheter based on signal generation by dialysis fluid flow.

METHODS: The feasibility of the color Doppler approach was evaluated utilizing a phantom. Furthermore, the technique was applied in 28 peritoneal dialysis patients, most of whom presented peritoneal catheter malfunction.

RESULTS: Color Doppler examination improved the catheter visualization, especially in cases in which the catheter is embedded between the intestinal loops. Furthermore, this technique highlighted catheter side hole occlusions by adhesions or intraluminal thrombi. The examination can be performed either during filling or draining of dialysis fluid.

CONCLUSIONS: The color Doppler ultrasound technique appears to be helpful in identifying problem-solving strategies in malfunctioning peritoneal catheters.