It is an option for patients who cannot be imaged with ultrasound, such as those with a high BMI.
SEATTLE—When patients cannot be imaged with ultrasound, CT fluoroscopy can be used safely and effectively for percutaneous nephrostomy tube placement, British researchers reported here at the Society for Interventional Radiology annual meeting.
CT fluoroscopy may be particularly helpful in patients who are difficult to image with ultrasound because of their anatomy or because they are undergoing other procedures, such as abscess drainage.
“Nephrologists and urologists will be very interested in our findings because they are often dealing with cases of obstruction of the urinary system,” said lead investigator Sriharsha Athreya, MD, an interventional radiology fellow at the Glasgow Royal Infirmary in Scotland. “We started using this approach for various reasons and we are finding that it is just working out fine for us.”
Dr. Athreya presented data from his institution’s initial experience of using CT fluoroscopy guidance as “the primary imaging modality” for performing percutaneous nephrostomy. Over an 18-month period, 25 percutaneous nephrostomies were performed on 22 patients (12 women) using CT guidance. The patients had a mean age of 56 years (range 18-88 years).
The causes of obstruction at the time of nephrostomy included benign stricture, calculi, and malignant obstruction. In some cases, the etiology was unknown. One patient had a previous cystectomy and one had a neurogenic bladder. Nine patients had severe hydronephrosis, 12 had moderate hydronephrosis, and one patient had mild hydronephrosis. The majority of patients had elevated serum creatinine levels and five patients were pyrexial.
No immediate complications resulted from any of the procedures. The overall success rate was approximately 95% at three months, Dr. Athreya said. He and his colleagues concluded that overall results of technical success and complications rates were within the range reported in the literature for the standard technique (ultrasound combined with CT guidance). This technique should be considered in patients who are difficult to image by other modalities.
“Performing nephrostomies under CT fluoroscopy is technically possible and it is a safe procedure,” Dr. Athreya told Renal & Urology News. He noted that CT fluoroscopy may be especially useful in patients with a high BMI. “These patients can be difficult to image with ultrasound, and in our series we had a couple of patients who had a joint procedure, with drainage of abscess at the same time and a nephrostomy put in. We also had a patient with a horseshoe kidney, and this is a very difficult patient in whom to perform an ultrasound.”