Elective LS is the preferred therapeutic modality for the treatment of spleen diseases requiring surgery16
. The indications for LS are basically the same as those for conventional laparotomy, although LS is less indicated for acute splenic rupture and severe splenomegaly (> 30 cm). Previously, LS was mainly used to treat ITP, since this condition is not accompanied by marked perisplenic varices, which makes the dissection of splenic pedicular vessels relatively easier and less technically complicated17
. Although LS is widely used for splenectomy in patients with hematological, oncological and infectious splenic diseases, it is relatively contraindicated for splenomegaly of over 30 cm. Laparoscopic resection is not that technically challenging in patients with splenomegaly secondary to hematological diseases, as these spleens have relatively long secondary pedicles and loose perisplenic ligaments. LS, however, is usually regarded as less safe for patients with splenomegaly complicated by portal hypertension18
. Coexisting perisplenic varices are prone to rupture and bleeding, while laparoscopy is less effective in controlling bleeding from secondary pedicular vessels. Most (86.2%) of our patients had hematological spleen diseases, especially ITP (70.4%), with a smaller percentage (9.4%) having hypersplenism and splenomegaly secondary to portal hypertension. LS via either the posterolateral or anterior approach showed good effectiveness and safety profiles in these patients without severe splenomegaly (< 30 cm), with a minimal conversion rate (1.5%) and a low bleeding risk.
The anterior approach is the most frequently used access approach in LS as it is suitable for any laparoscopically eligible patient. This approach permits easy access to the omental pouch and great splenic vessels, similar way to laparotomy9
. Using this approach, the splenogastric ligament is transected before the other perisplenic ligaments. The upper pole of the spleen can be elevated using a pair of atraumatic hemostatic forceps to allow ultrasonic dissection. In patients with extensive upper pole adhesions, the splenogastric ligament can be dissected after the other perisplenic ligaments.
Interruption of arterial inflow into the splenic hilum can reduce spleen volume and minimize the risk of bleeding during the dissection of secondary pedicular vessels. In most patients, the main trunk of the splenic vein is located superficially, allowing it to be transected along with the splenic artery. Excessive dissection may result in injury to the pancreatic tail or massive bleeding. Hilar vessel control is usually completed by using Endo-GIA at the pancreatic tail19
. This technique requires the use of expansive instruments but is associated with a high risk of pancreatic leakage following splenectomy. We therefore transected the secondary rather than the primary pedicular vessels using the LigaSure sealing device and/or laparoscopic clips, reducing the cost of LS and the risk of postoperative leakage, but prolonging the operating time. The anterior approach is awkward in dissecting splenic retroperitoneal attachments as well as in visualizing and controlling hilar vessels10
. These technical disadvantages result in a longer operation time and increase the risk of iatrogenic injuries.
LS using the lateral or posterolateral approach was first described soon after the anterior approach was introduced12
. The posterolateral approach is more suitable for obese patients scheduled for elective LS as it is more difficult to visualize and dissect the splenogastric ligament enriched with adipose tissues. Transection of the splenocolic ligament permits the forward dissection of the splenorenal ligament, an approach that entails less dissection of adipose tissue and enables better visualization of the splenic hilum. Following adequate mobilization of the splenic pedicle, the secondary pedicular vessels are mobilized and transected upwards. The direct visualization in this approach renders it easy to manipulate pedicular vessels, minimizing the risk of incident bleeding and iatrogenic injury to the pancreatic tail. However, the lateral or posterolateral approach is less efficient for LS in patients with extensively severe splenomegaly (< 30 cm) 15
, since the huge space-occupying spleen cannot be flipped towards the anterior side prior to ligation of the splenic artery.
The primary advantages of LS relative to conventional laparotomy include its minimal invasiveness and better cosmetic outcomes due to the small trocar incisions made in the abdominal wall20
. We found that patients can benefit similarly from LS via both approaches, as shown by postoperative recovery, including the resumption of off-bed activities, bowel movement and oral intake. The primary disadvantages of LS compared with open splenectomy include longer operation time and higher bleeding risk21
. However, our results demonstrate that the posterolateral approach significantly shortens the LS operation time and reduces the volume of intraoperative blood loss compared with the anterior approach. The lower frequency of laparoscopically uncontrollable bleeding reduces conversion to an open procedure. We observed a very low conversion rate, comparable in patients who underwent LS via the anterior and posterolateral approaches. However, conversion in the three patients was mainly due to extensive perisplenic adhesions rather than bleeding. The reduction in intraoperative blood loss also minimizes the requirement for blood transfusions, although none of our patients who underwent LS via either approach require a transfusion. This benefit is more clinically significant for patients with surgical spleen disorders as they, especially those with complicating coagulopathy, such as ITP, are more prone to surgical bleeding and transfusion-associated adverse effects.
Iatrogenic pancreatic injury is another common procedural complication following splenectomy, resulting in a severe and even fatal outcome in some patients22
. The occurrence of pancreatic injury, such as pancreatic leakage, pancreatic bleeding, and pancreatitis, is frequently underestimated, as most patients with complicating pancreatic conditions are asymptomatic. Pancreatic injuries secondary to splenectomy occur mainly during the dissection of the pancreatic tail in proximity to splenic hilum. The rate of pancreatic injury is reported to be up to 16% in patients undergoing laparotomy, but only 1-2% in patients undergoing LS23
. The rate (3.4%) of pancreatic leakage in our patients who underwent LS via the anterior approach was similar to that of previous reports, whereas use of the modified posterolateral approach reduced the rate of pancreatic leakage to zero. Inappropriate disposition of the stapler transecting the pancreatic tail and the splenic hilum results in a very high risk of pancreatic leakage. The modified posterolateral approach offers a better visualization of the splenic hilum and facilitates the dissection of the pancreatic tail away from the hilum, thus minimizing the occurrence of pancreatic tail injury and leakage. The monitoring of amylase concentrations in serum and/or peritoneal fluid can be used to detect occult pancreatic leakage22
, although abdominal CT scan may identify nonspecific pancreatic tail swelling. Pancreatic leakage following LS is usually transient in duration and mild in severity, with most patients requiring symptomatic treatment alone. Persistent and patent peritoneal drainage is the most effective method of controlling pancreatic leakage, minimizing secondary peritonitis and peritoneal abscess24
. The five patients who experienced pancreatic leakage following LS via the anterior approach all responded well to peritoneal drainage, and resolved without significant sequelae. Minimization of pancreatic leakage was the primary contributor to the shorter hospital stay in the PLLS than in the ALS group.
This study had several limitations. The use of either the anterior or posterolateral approach was at the discretion of the surgeon, a non-randomized patient assignment that may have resulted in patient selection bias. In addition, this analysis was retrospective in design, and surgeons were not blinded to the LS approach, thus suggesting that our results may have been subject to observation and confounding biases. To date, however, no prospective randomized control study has compared the effectiveness and safety outcomes in patients undergoing LS via the lateral/posterolateral and anterior approaches.