Laparoscopic orchiopexy versus traditional inguinal incision orchidopexy for palpable undescended testes in cryptorchidism

Background (cid:0) Laparoscopic orchidopexy (LO) has become a standard procedure for the treatment of nonpalpable undescended testes. Nevertheless, the use of LO for palpable undescended testes still remains controversial. The aim of this study was to explore the impact of laparoscopic orchiopexy procedure on palpable undescended testes in children suffering from cryptorchidism. Methods: A retrospective study was performed for LO and traditional inguinal incision orchidopexy (TIO) carried out to treat palpable undescended testes. In total, 291 children aged 9 months to 96 months with either left or right side palpable inguinal canalicular testes were included. 170 patients received LO and 121 patients received TIO. Age, operative time and clinical outcomes of the patients were reviewed. Independent t test and Fisher’s exact test were performed by using the SPSS 25.0 software. Results: In the younger groups, the mean operative time (younger than 1 year old, 30.50±5.88 vs. 39.86±6.11 min; 1-2 years old, 34.43±6.65 vs. 40.23±8.74) and postoperative normal activity time (younger than 1 year old, 1.20±0.40 vs. 2.12±0.48 days; 1-2 years old, 1.58±0.50 vs. 2.02±0.43 days) of LO were signicantly shorter than those in the TIO group ( P <0.05). The operative time of LO was signicantly longer than that in the TIO group in older groups (aged>3 years old). 47 of 49 cases (95.9%) of patients aged less than 1 year old were treated by LO successfully. Among the patients aged 1-2 years, 80 of 86 cases (93.0%) successfully completed LO. Totally, 43 cases were transferred to inguinal incisions. Conclusion: LO appropriate choice for palpable testes, in children younger than 2 years old. The percentage of successful LO decreased with age.


Background
Cryptorchidism or undescended testes (UDT) are a common genital malformation in boys. In similar studies performed in different countries, the prevalence of cryptorchidism varies from 2% to 8% [1]. The incidence of undescended testes in premature infants and/or infants with a birth weight of <2500 g varies from 1.1% to 45.3%, and the incidence of bilateral presentation among these patients was 50% to 75% [2]. Nearly 80 percent of undescended testes are palpable [3]. Traditional inguinal incision orchiopexy (TIO) is recommended after 6 months of age [4]. Laparoscopic orchidopexy (LO) is a standard procedure for the treatment of nonpalpable undescended testes [5]. However, LO for palpable undescended testes still remains controversial. The LO procedure has not been recommended by any organization yet. While many literatures have reported LO as a great and safe option for the treatment of palpable undescended testes, regardless of the age of the patients [6,7], this study compared LO with TIO in children with palpable undescended testes who were treated at the hospital of the authors in the past 5 years.

Methods
This study was approved by the Ethics Committee of The First People's Hospital of Lianyungang. Here, a retrospective study of LO and TIO was conducted on patients admitted from August 2014 to August 2019. In total, 291 children with either left or right side palpable inguinal canalicular testes were included (Table 1). LO was performed on 170 patients aged from 9 months to 48 months (mean 16.62 ± 8.43 months), including 74 patients at the left side and 96 patients at the right side. 121 patients aged from 9 months to 96 months (mean 18.37 ± 15.35 months) received TIO, including 50 patients at the left side and 71 patients at the right side. All patients had unilateral palpable undescended testes and the testicles could not be drawn into the scrotum in the physical examination. Age, operative time, the proportion of closure of internal inguinal ring (IIR), and clinical outcomes of the patients were reviewed. Follow-up visits were performed to assess the condition of postoperative testes.
The patients were placed in a supine position under general anesthesia. Then, the operating table was tilted to 15-20 degrees with the head of the patients below their feet. A 5-mm umbilical incision was made along the superior border of umbilicus. First, a 5-mm trocar was inserted into the umbilical incision. CO2 pneumoperitoneum was established routinely at a pressure of 8-10 mmHg. The lens (30 degrees) was placed into the abdominal cavity to explore the IIR. If the IIR was closed, the inguinal incisions were transferred. If the IIR was open, the other two 5-mm trocars were placed at the subcostal midclavicular line. Alternately, two graspers were used to pull the testes from the inguinal canal into the abdominal cavity. If the testicle could be pulled into the abdominal cavity, laparoscopic dissection and orchiopexy were performed. The gubernaculums testis (GT) was cut off in the abdominal cavity and the peritoneum around the IIR was cut off completely, and the vessels and deferent duct were dissected for adequate testicular mobilization before the testicle was retracted to the scrotum for orchiopexy by using a clamp inserted from scrotum and guided by a suction tube. The suction tube was inserted from the ipsilateral trocar through the inguinal canular and eventually sent out from the scrotum incision. A clamp was inserted into the suction tube [ Fig. 1] to retract it until the clamp could be smoothly pushed into the abdominal cavity. After bringing the testis into the scrotum, 2-3 sutures were made to x the testis inside the scrotum. If the testicle could not be pulled into the abdominal cavity, the inguinal incisions were transferred.
In the TIO group, the GT was cut off through an inguinal incision and a standard inguinal orchiopexy was performed. The operations in both groups were done by different surgeons in the same period.
Independent t test and Chi-square test were performed by using the SPSS 25.0 software. The normality of data was checked before the t-test (U-test was used if the data did not obey normal distribution). Chisquare test was performed (for cell(s) with n<5, Fisher's exact test was performed).  (Fig. 2, Fig. 3) The transferred 43 cases were still deemed as subjects in the LO groups. In the younger groups, the mean operative time (younger than 1 year old, 30.50±5.88 vs. 39.86±6.11 min; 1-2 years old, 34.43±6.65 vs.

Results
40.23±8.74) and postoperative normal activity time (younger than 1 year old, 1.20±0.40 vs. 2.12±0.48 days; 1-2 years old, 1.58±0.50 vs. 2.02±0.43 days) of LO were signi cantly shorter than those in the TIO group (P<0.05). The operative time of LO was signi cantly longer than that in the TIO group in older groups (aged>3 years old). There were no statistically differences in postoperative normal activity time between LO and TIO in the elder group (aged>3 years old). (Fig.4, Fig.5) The follow-up also showed no difference between the two groups. (Table 2) Discussion In recent years, LO has been mostly applied to the treatment of nonpalpable undescended testes and peeping testicles. The results showed that laparoscopic surgery was more e cient and more su cient than the traditional surgery in terms of testicular dissection. To date, laparoscopic surgery has become a gold standard for nonpalpable undescended testes [3,8]. However, the application of LO for palpable undescended testes still remains controversial.
In 1995, Docimo et al. [9] rst reported the use of LO treatment for palpable undescended testes. Then, Riquelme et al. indicated that LO was a safe procedure for patients with palpable undescended testes, and no more complications were found compared to the traditional surgery. Of 192 patients studied, only one case was converted to TIO [7,10]. However, based on the surgeon's preference and experience, inguinal and prescrotal techniques are still recommended for palpable UDT undergoing surgery [11].
Bianchi rst described a scrotal approach for the management of cryptorchidism in 1989 [12]. Evidence showed that the scrotal approach had a success rate of 88-100% for palpable UDT [13]. However, the general view is that the outcome of the operation tends to be poorer when more proximal testes are involved due to inadequate exposure. [14] As far as the etiology of cryptorchidism is concerned, testicular descent from the abdominal cavity to scrotum occurs between 25 and 35 weeks of gestation [15]. Testicular descent into scrotum relies on a ligament called gubernaculums testis (GT). Many uncertain reasons prevent testicular descent, and the testicle remains in the abdomen or groin in cryptorchidism [16]. Meanwhile, the GT remains as a ligament and prevents the extension of the testicle into the scrotum.
During the surgery of orchidopexy, it is required to cut off the dysplastic GT as the main procedure to make adequate mobilization of testicles. In LO for palpable undescended testes, if the testicles can be pulled back into the abdominal cavity, it is more convenient to use the laparoscopic approach to cut off the dysplastic GT compared to the traditional approach. The subsequent mobilization of testicles will be su cient and e cient. Therefore, whether the testicles can be pulled back into the abdominal cavity is a key factor.
According to relevant literature reports, the incidence of cryptorchidism associated with an inguinal hernia is 56% [17]. More than 92% of patients with unilateral palpable undescended testes have an ipsilateral open IIR at a median age of 14.9 months [18]. This study showed that in 98.0% of children under 1 year old, their IIR was open and 97.9% of the testicles could be pulled into the abdominal cavity to accomplish the LO procedure. In this study, it was also found that the opening of IIR did not necessarily cause hernia.
The open IIR is generally present in cryptorchidism. The proportion of open IIR decreased gradually with the increasing age. From 2008, guidelines recommended that surgery should be performed before the child's rst birthday to minimize the risk of impaired fertility [19]. At this recommended age, almost all IIR is open, which is an advantage for laparoscopy.
This study showed that palpable undescended testes associated with an ipsilateral open IIR were con rmed during more than 90% of laparoscopy (91.7) even in patients younger than 2 years of age. It seemed that LO was not suitable for the majority of elder children, especially those over two years of age.
If IIR was closed, it would be very hard to complete LO surgery, since the testicles could not be pulled back into the abdominal cavity. Reopening the closed IIR was tried, but it was found that it was still hard to pull back the testicles and the risk of damage to the vas deferens and spermatic vessels was increased. Thus, a relatively conservative routine was taken by transferring to inguinal incisions when the IIR was closed. 43 out of 170 cases were converted to open inguinal approach. Combination with an inguinal incision may be necessary when the LO procedure is unsuitable for elder children, although further study is needed.
With regards to the closure of the peritoneal defect after the testicle has been mobilized during LO, when no ligature or suture was contemplated, the operative time decreased signi cantly. Ra ei et al. [20] carried out a randomized controlled trial to evaluate the no-ligation method in children. It was concluded that herniotomy without sac ligation in children saved signi cant time and also prevented other possible complications such as nerve damage and spermatic cord injury. Riquelme's study showed that it is unnecessary to close the internal inguinal ring during LO [21]. In the above study on the staged treatment of LO, it was found that the peritoneum of the unsutured IIR in the rst stage of the operation was completely closed during the second stage of the operation. Khairi et al. [22] carried out a prospective study to compare the difference between the IIR conventional suture group and non-closed IIR group during LO. It was concluded that the closing of the peritoneum over the IIR is not necessary in LO, saving operative time and effort while not increasing the risk of recurrent inguinal hernia [23,24].
The main controversy of LO still remains on abdominal interference and anesthesia with tracheal intubation, which may cause more risks to patients. No additional complications of LO were observed in this study. Nevertheless, further studies are needed. Accompanied with the advance of the technique, incisions of Laparoscopic surgery are becoming smaller and their cosmetic impact is becoming less. Additionally, LO imitates the natural descent procedure of testes more closely.

Conclusions
LO is an appropriate choice for treating palpable undescended testes, especially in children younger than two years old. The percentage of successful LO decreased over an increasing age.

Availability of data and materials
The datasets used and/or analyzed in the current study are available from the corresponding author on reasonable request.

Competing interests
The authors declare no competing interests.

Funding
This research did not receive any speci c grant from funding agencies in the public, commercial, or notfor-pro t sectors.
[23] Mohta A, Jain N, Irniraya KP, Saluja SS, Sharma S, Gupta A: Non-ligation of the hernial sac during herniotomy: a prospective study. Pediatr Surg Int 2003, 19 (6) *Independent samples t-test was performed between the age of the two groups. ‡ Chi-square test was performed for different sides of the two groups. Hernia recurrence(N) 0 0 P-value<0.05 was considered statistically significant.
*Independent samples t-test (two-tailed) was performed (normality of data was checked before t-test (if normal distribution was not obeyed, U-test was used)) ‡ Chi-square test was performed (for cell(s) with n<5, Fisher's exact test was performed Figure 1 The testicle was retracted to the scrotum for orchiopexy by a clamp inserted from scrotum and guided by a suction tube.

Figure 2
The proportion of open patent ring in LO groups over age. P-value<0.05 was considered statistically signi cant. Fisher's exact test was performed.

Figure 5
Comparison of postoperative normal activity time between LO and TIO