Waingankar N et al, 2014: Calyceal diverticula: a comprehensive review.
Waingankar N, Hayek S, Smith AD, Okeke Z
The Arthur Smith Institute for Urology, Hofstra North Shore-LIJ School of Medicine, New Hyde Park, NY.
University of Pittsburgh Medical Center, Pittsburgh, PA.
Calyceal diverticula are rare outpouchings of the upper collecting system that likely have a congenital origin. Stones can be found in up to 50% of calyceal diverticula, although, over the combined reported series, 96% of patients presented with stones. Diagnosis is best made by intravenous urography or computed tomography urogram. Shock wave lithotripsy (SWL) is an option for first-line therapy in patients with stone-bearing diverticula that have radiologically patent necks in mid- to upper-pole diverticula and small stone burdens. Stone-free rates are the lowest with SWL, although patients report being asymptomatic following therapy in up to 75% of cases with extended follow-up. Ureteroscopy (URS) is best suited for management of anteriorly located mid- to upperpole diverticular stones. Drawbacks to URS include difficulty in identifying the ostium and low rate of obliteration. Percutaneous management is best used in posteriorly located mid-to lower-pole stones, and offers the ability to directly ablate the diverticulum. Percutaneous nephrolithotomy remains effective in the management of upperpole diverticula, but carries the risk of pulmonary complications unless subcostal access strategies such as triangulation or renal displacement are used. Laparoscopic surgery provides definitive management, but should be reserved for cases with large stones in anteriorly located diverticula with thin overlying parenchyma, and cases that are refractory to other treatment. This article reviews the current theories on the pathogenesis of calyceal diverticula. The current classification is examined in addition to the current diagnostic methods. Here we summarize an extensive review of the literature on the outcomes of the different treatment approaches.
Rev Urol. 2014;16(1):29-43. Review. FREE ARTICLE
Calyceal diverticula containing stones are not uncommonly encountered in the image evaluation of patients with stone disease. Treatment is indicated when patients are symptomatic. This article is a comprehensive review of this topic.
The diverticles might have a patent or closed neck and it is suggested that SWL can be the first line treatment for the previous group of patients. The diagnostic prerequisite is thus that either a retrograde pyelography or a urography has demonstrated a communication between the calyceal cavity and the rest of the collecting system.
Although PNL will result in a higher stone free rate, that technique might be difficult to carry out and is usually associated with significantly more complications than SWL.
Despite a variable outcome with SWL, it is of interest to note that up to 75% of patients treated with this method became asymptomatic in long-term follow-up! By using SWL a non-invasive approach is possible, but it should be noted that both stone size and composition are important determinants for decisions on whether SWL or PNL should be chosen.