**6. Technical considerations**

#### **6.1 Transperitoneal vs. retroperitoneal laparoscopic nephrectomy**

The advantages of a transperitoneal approach include a wider working space and more easily identifiable anatomical landmarks. However, it also requires bowel mobilization and adhesiolysis in cases of previous transperitoneal abdominal surgery. The retroperitoneal approach, on the other hand, allows extra-peritoneal dissection and direct access to the renal hilum while avoiding the need for bowel mobilization and adhesiolysis. Limitations of this approach include the smaller working area in the retroperitoneal space, and reduced traction and instrument mobility.

A few technical considerations are particularly important with the retroperitoneoscopic approach. Proper balloon dilation in avascular plane between the psoas fascia posteriorly and Gerota's fascia anteriorly is necessary to mobilize the Gerota's fascia and expose the psoas muscle, the ipsilateral peritoneal reflection, the ureter, the IVC on the right side and the aortic pulsations on the left side. After balloon dilation, the renal hilum is readily accessible and thus the size of the renal mass or kidney is not a significant issue during the hilar dissection. Mobilization of the specimen along avascular planes is important to further develop and enlarge the retroperitoneal space as the dissection proceeds.

#### **6.2 The lower pole approach in retroperitoneoscopic radical nephrectomy**

In routine retroperitoneal LRN, renal vessels at the hilum are accessed by the latero-posterior space (LPS). Using this approach, the dissection of latero-conal fascia and quadratus lumborum fascia allows the entry into avascular area, bounded by the quadratus lumborum, the psoas major, and Gerota's fascia for the purpose of renal pedicular control [10]. However, the narrow space of manipulation is intrinsically subject to poor anatomical identification and a greater risk of renal pedicle injury especially in patients with obesity, larger tumors, or renal pedicle adhesions. Yuan et al., in 2018, published a new technique, the lower pole (LP) approach for the control of renal pedicular vessels in retroperitoneal LRN [11]. In this approach, The dissection of the renal latero-anterior space preceded that of the LPS. Upon the establishment of the working space the anterior and posterior renal fasciae were transected 3.0 cm below the lower pole [11].

While a retrospective comparative study suggested improved operation times, blood loss, and time to commencement of diet with retroperitoneal LRN [12]; Recently published articles with prospective randomized series demonstrated no statistically difference in the overall operative morbidity in transperitoneal versus retroperitoneal radical nephrectomies [13–16]. Nevertheless it is remarkable that the retroperitoneal group, compared to the transperitoneal approach, was associated with a shorter total time to control the renal artery and quicker control of the renal vein [13]. Most studies have demonstrated equal efficacy for both techniques and the choice of the retroperitoneal or transperitoneal approach depends mostly on surgeon's experience and choice [13].

### **6.3 Removal of dissected specimen**

This is another area of continued controversy -whether to morcellate or to remove the intact specimen with additional incision. We retrieve the specimen by additional incision using an endobag at our institute.

The major concern with morcellation is pathological interference and tumor spillage [17–19]. Although, Ono et al. have reported that proper morcellation does not hamper the pathological stage [20]. In a recent study, Varkarakis et al. stated that, intact extraction and morcellation are both acceptable options for specimen removal, and the choice should depend on surgeon and patient preferences [21].
