Laparoscopic Heminephrectomy in Horseshoe kidney: single-center experience of four cases

Abstract
Background
Horseshoe kidney (HSK) is the most common congenital fusion anomaly and found in 1 in 400 of the general population (Grainger et al. in Ir Med J 76:315–317, 1983 Jul). Impaired drainage due to anomalous anatomy leads to ureteric obstruction resulting in hydronephrosis and nonfunctioning kidney.
Conventionally heminephrectomy is done by open technique; however, in the era of minimally invasive surgery, laparoscopic heminephrectomy in HSK has been described. Kidney location, aberrant vasculature and isthmus division are the most common obstacle encountered by the operating surgeon. Here we report our single-center experience in laparoscopic heminephrectomy in four patients with HSK.

Methods
Retrospective data were analyzed for four cases of laparoscopic heminephrectomy for nonfunctioning moiety in HSK operated between 2012 and 2020. Of these four patients, one case was converted to open approach in view of intra-operative bleeding. Computed tomography urogram (CTU) was done pre-operatively in all patients. Laparoscopic surgery was performed via transperitoneal approach.

Results
The mean age of the patients was 37 ± 5.38 years. Flank pain was noted in all cases while dysuria seen in two patients and one patient had fever. Mean operative time was 145 ± 26.92 min and estimated blood loss was 85 ± 55 ml. Various techniques for isthmectomy and lower pole resection were used including use of monopolar hook in laparoscopic suite, Ligasure and bipolar scissor in minimal invasive milieu and monopolar cautery in laparoscopic conversion to open procedure. Histopathological examination revealed chronic pyelonephritis in three cases and squamous cell carcinoma of renal pelvis in one case which was converted to open.

Conclusions
Laparoscopic heminephrectomy in HSK is doable. Preoperative CT urography along with CT angiography may provide important anatomical and vascular information which reduces intra-operative risks of vascular injury or calyceal entry. Vascular control of isthmus and transection of dilated and thinned out lower pole with cauterization of pelvicalyceal mucosa will provide uneventful surgical course.