The urachus is found between the umbilicus and bladder during the prenatal period. In normal cases, the urachus closes and becomes the median umbilical ligament before birth. The urachal remnant is the remaining urachus after birth [7] and is associated with umbilical infection. Local treatment such as drainage or the use of antibiotics is effective; nonetheless, 30% of the patients who receive such treatment experience re-infection [8]. Therefore, the curative treatment is resection of the urachal remnant.
Recently, endoscopic resection has been commonly used; however, a standard method for laparoscopic urachal resection is lacking. Both the peritoneal and retroperitoneal methods have been suggested [3–6].
It is easy to identify the urachus using the peritoneal approach because the urachus adheres to the peritoneum. During surgery, resecting the urachus along with the peritoneum is easy, provided that the peritoneal cavity is large enough for the endoscopic technique. However, this approach is associated with a risk of intestinal injury and postoperative intestinal adhesions. The retroperitoneal approach is the most appropriate method for reducing the risk of intestinal injury and adhesions. However, the cavity is often too small to set the port. As described above, the urachus adheres to the peritoneum, and separating them is difficult. Locating the urachus near the umbilicus is particularly difficult because the urachus is very thin.
The optimal position of the port remains undetermined. In our method, there were three ports: the umbilical camera port and left and right bilateral abdominal ports. This position was reasonable because of the endoscopic triangle. Considering the central camera, the central target organ and bilateral forceps were appropriate for endoscopy and provided the best ergonomic positioning. Urachal resection was easy, especially around the bladder. However, the disadvantage of this position was the initial part of the endoscopy. After setting the camera and bilateral ports, the camera and the urachus were close to each other. In endoscopic surgery, it is difficult to resect a close target because of the reduced visual field; therefore, hollowing of the umbilicus before endoscopy is crucial.
Three significant points need to be considered for laparoscopic urachal resection. The first is the thickness of the abdominal wall. In our case, a thick abdominal wall was one of the difficulties that we encountered; the time for the initial part of the operative correlated with wall thickness (data not shown). Patients with an abdominal thickness > 2 cm were more likely to have longer operative times (Fig. 3). In patients with an abdominal wall thickness > 2 cm, setting the umbilical camera port was difficult; thus, we considered changing the camera port to the lateral abdominal port [9]. The second point is cosmetics. Most of the patients in our study were young. The appearance of the surgical site is critical, especially for young women. Although the urachal remnant is not malignant, caution should be exercised when performing surgery to ensure patient satisfaction and improvement of the quality of life after the operation. Our umbilical repair method is easy to perform, and the umbilicus retains a natural appearance; the lateral ports used are 5 mm in size, which is appropriate for achieving good cosmetic results (Fig. 4). Considering cosmetic aspects, the laparoendoscopic single-port surgery may be another suitable option [6, 10]. The third point is infection control before surgery. The severity of umbilical infection was not related to the success of the surgery. In Case 8 (Table 1, Fig. 5), the infection was very severe, requiring drainage and debridement. Five months after this treatment, successful urachus resection was performed within the median operative time, without any adverse events (Table 2). Infection control for at least 4 months before the operation is recommended (Fig. 6).
This study had a few limitations. First, it included a small number of cases, resulting in an insufficient number of treatment options. Second, the patients’ quality of life was not evaluated in this study. Future studies should enroll more patients and evaluate patient satisfaction after the procedure.
In conclusion, we present the laparoscopic as the best method for urachal resection. This method may be recommended for young patients with an abdominal wall thickness of < 2 cm. In addition, sufficient time (> 4 months) is required for infection control before the operation.