Percutaneous Management of Calyceal Diverticula: An American Experience

Abstract

Calyceal diverticula are congenital, non-secretory, urothelium-lined cavities within the kidney. They communicate with the collecting system via narrow infundibula and fill retrogradely with urine. Some diverticuli remain asymptomatic over time, while others cause flank pain, hematuria, and recurrent urinary tract infections or develop calculi. While asymptomatic diverticula can be managed conservatively, symptomatic or stone-containing diverticula should be treated. Due to the development of minimally invasive methods for the treatment of symptomatic diverticula, open surgical techniques such as unroofing, marsupialization, and open diverticulectomy have become obsolete. Currently available minimally invasive techniques for treating calyceal diverticula include extracorporeal shock wave lithotripsy (ESWL), ureteroscopy, laparoscopy, and percutaneous nephrolithotomy (PNL). ESWL does not lead to adequate stone-free rates and does not allow for simultaneous ablation of the diverticular cavity. Ureteroscopy is an acceptable form of treatment for upper or mid pole diverticula and involves incision or balloon dilation of the diverticular neck followed by stone removal and obliteration of the diverticular cavity, if possible. This technique is difficult to perform in lower pole lesions due to the limited flexion capabilities of flexible ureteroscopes, and may not be possible in the case of diverticula with very small ostia. Laparoscopy is generally reserved for anteriorly located diverticula with minimal surrounding parenchyma. This technique is successful in experienced hands, but operative times are often substantially longer than with other modalities. PNL provides the highest stone-free, symptom resolution, and diverticular resolution rates but can pose a significant challenge to urologists owing to the small working space within the diverticular cavity and the difficulty associated with safely maintaining wire access. Additionally, the majority of diverticula are located in the upper pole, and pleural complications such as hydro- or hemothorax associated with supracostal, upper pole access are of significant concern. Here we describe a single stage, infracostal approach for the percutaneous management of symptomatic calyceal diverticula.