Safety and Efficacy of Laparoscopic Percutaneous Extraperitoneal Closure for Inguinal Hernias and Hydroceles in Children: A Comparison with Traditional Open Repair

Introduction

For a long time, the repair of indirect inguinal hernias and hydroceles in children had been performed through an inguinal crease incision as the traditional open repair (OR). With the advent of laparoscopic techniques, the laparoscopic repair of inguinal hernias and hydroceles has gradually become widespread, even in the pediatric population. In 2008, we adopted laparoscopic percutaneous extraperitoneal closure (LPEC), which is a laparoscopic herniorrhaphy developed by Takehara et al. ¹ in 1996. At first, the indication for LPEC was limited to female patients, but it has been expanded to any cases of inguinal hernia and hydrocele, irrespective of sex, age and body weight. Theoretically, LPEC should offer advantages over OR in terms of its high ligation of patent processus vaginalis (PPV) and routine investigation and intervention for the contralateral side. The purpose of this study was to perform a retrospective analysis of our experience to assess the safety and efficacy of LPEC compared with OR.

Subjects and Methods

This study was conducted in a tertiary-care teaching hospital from April 2008 to December 2012. It was approved by the hospital's ethics committee. All of the patients who were younger than 16 years old with an inguinal hernia or hydrocele were enrolled in this study. Inguinal hernias and hydroceles associated with undescended testes were not indicated for LPEC and were excluded from this study. Regarding the surgical procedures, OR and LPEC were explained to the parents of the patients if their child met the indications for LPEC. OR or LPEC was selected according to parental preference after informed consent was given. The protocols for pre- and postoperative care were the same for both procedures. Every patient visited the hospital 1 week and 1 month after the operation to assess wound healing, in addition to the size and position of the testes if the patient was male. Patients who did not exhibit any remarkable complications were removed from follow-up. Every operation was performed with the patient under general anesthesia induced by anesthesiologists.

LPEC was initially limited to females and was extended to males in April 2009. The indications for the operation (inguinal hernia with or without incarceration, hydrocele), duration of the operation, intra- and postoperative complications, recurrence, day surgery or not, contralateral PPV, and the incidence of a metachronous contralateral hernia were investigated.

Results

Between April 2008 and December 2012, 488 pediatric patients underwent 493 operations for inguinal hernias or hydroceles (Table 1). In total, 326 patients (125 males and 201 females) received 328 LPEC procedures. Redo LPEC for recurrence was performed in 2 patients, both of whom had received initial LPEC for inguinal hernias in our institute. The mean age of the LPEC group was 55.8±38.7 months, and the mean body weight was 16.0±8.4 kg. In total, 162 patients (140 males and 22 females) underwent 165 OR procedures. Three patients had the second operation for contralateral inguinal hernia in this period. The mean age of the OR group was 38.3±39.3 months, and the mean body weight was 13.0±8.8 kg. There were significant differences in the sex ratio, age, and body weight between the LPEC and OR groups.

Twenty patients (6.1%) in the LPEC group (10 males and 10 females) and 18 patients (10.1%) in the OR group (14 males and 4 females) presented with an incarcerated hernia (P=.07).

Hydroceles were treated in 17 (5.2%) patients by LPEC and in 39 (23.6%) patients by OR. In all of the patients with hydroceles treated by LPEC, patent internal inguinal rings were confirmed and ligated laparoscopically.

The length of the operation was compared except for the cases with an additional operation (LPEC versus OR) (Table 2). In the male unilateral cases, there was no significant difference in the duration of the operation between the LPEC (36.7±7.7 minutes) and OR (37.7±12.6 minutes) groups. In the male bilateral cases, the duration of the operation was shorter in the LPEC group (46.8±9.9 minutes) than that in the OR group (83.8±31.6 minutes) (P<.01). In the female unilateral cases, the duration of the operation was longer in the LPEC group (37.2±8.0 minutes) compared with that in the OR group (29.0±13.0 minutes) (P<.01).

In the LPEC group, 4 of the 189 patients (2.1%) who were scheduled to undergo day surgery failed to be discharged on the day of the operation. In the OR group, 1 of 43 patients (2.3%) who were scheduled to undergo day surgery failed to be discharged on the day of the operation. There was no significant difference in the rate of successful execution of day surgery between the two groups (LPEC, 97.8%; OR, 97.6%; P=1.00).

The laparoscopic procedure was completed in all cases in the LPEC group, and there were no open conversions. There were no intra- or postoperative complications, including testicular atrophy and elevated testes, in either of the groups, as far as we were able to observe.

Three postoperative recurrences were found in the LPEC group (0.92%), and none was reported in the OR group (0%). The causes of the recurrences were a peritoneal “skip” in 2 cases (technical problem) and a slack ligation in 1. Two patients underwent redo LPEC, and 1 patient underwent OR. There was no significant difference in the incidence of recurrence between the two groups (P=.55) (Table 3).

In the LPEC group, 170 of the 285 patients (59.6%) with a unilateral diagnosis had contralateral PPV, all of which were ligated preclusively. No postoperative metachronous contralateral hernias were experienced after LPEC. In the OR group, 3 of the 130 patients (2.3%) with a unilateral diagnosis had metachronous contralateral hernias. The incidence of metachronous contralateral hernia after LPEC was significantly lower than that after OR (LPEC, 0%; OR, 2.3%; P=.03) (Table 3).

In addition, we performed 23 operations (3 in the LPEC group and 20 in the OR group) for metachronous hernias during the study period, and all of these patients underwent OR as the initial operation.

Discussion

Conventional OR has been an established standard procedure used for the treatment of pediatric inguinal hernias and hydroceles for a long time. Thus, any alternatives should be as safe and effective as OR and would be expected to have some advantages over OR.

Our present data showed that there were no intra- or postoperative complications in the LPEC group and that there was no differences in the recurrence rate between LPEC and OR. In addition, the rate of successful execution of day surgery in the LPEC group was similar to that in the OR group.

Recently, the reported recurrence rates of laparoscopic repair for inguinal hernia have varied from 0% to 2.6%^1–6 and are comparable with those of OR, which was reported to range from 0% to 3.8%. ⁷ Takehara et al. ¹ reported that no complications occurred during or after surgery and that the recurrence rates was 0.73% in a large series of 972 LPEC procedures. Endo et al. ² reported that the incidence of intraoperative injuries to the reproductive system was lower in LPEC compared with OR (0% versus 0.6%, P<.005) and that the recurrence rate was 0.2% in a large series of 1257 LPEC procedures. Our data were consistent with the data from these large series.

Although the duration of the operation was longer in the LPEC group than that in the OR group in female unilateral cases, it was shorter in male bilateral cases. During LPEC, the need for dissection of the spermatic cord and testicular vessels from the peritoneum was minimized, which may have led to the shorter operation in the male bilateral cases.

Our data and the previous reports suggest that LPEC can be a safe and effective alternative to conventional OR. As far as the indications are concerned, LPEC is also comparable to OR. Although the indication was initially limited to females, LPEC is now indicated for all indirect inguinal hernias, including incarcerated hernias and hydroceles, except for those associated with undescended testes.

OR of incarcerated inguinal hernias is reported to be associated with higher rates of morbidities, including recurrence and testicular atrophy, compared with laparoscopic operations.^8,9 Although we experienced one recurrence as a postoperative hydrocele in the LPEC group, no other serious complications were found in our series. This may be because we can avoid the dissection of edematous tissues, which potentially leads to serious complications, and confirm the status of reduced organs directly in LPEC.

In our series, hydroceles were also successfully treated in the LPEC group. We could visualize the PPV laparoscopically in every case of hydrocele. Abdominoscrotal hydroceles were also clearly visualized by laparoscopy and were opened electrically, followed by closure of the PPV. Although the reports on the laparoscopic approach for hydroceles have been limited,^10–12 LPEC appears to be a useful procedure for hydroceles, as well as for inguinal hernias.

Our data indicated that LPEC has another advantage over OR in addition to the better cosmetic results. In the LPEC group, there were no metachronous hernias, which occur in 10%–30% of the patients who undergo unilateral OR. ¹³ Laparoscopic detection of the contralateral PPV enabled us to obliterate it simultaneously and to prevent the occurrence of a metachronous inguinal hernia. The reported incidence of a contralateral PPV in patients with a unilateral inguinal hernia was 40%–60%, ¹³ and it was 60% in the LPEC group in our study. Although the repair of an asymptomatic PPV is controversial, we treated all of the contralateral PPVs, including those hidden by a peritoneal slit or veil, to prevent the occurrence of a metachronous hernia. In the OR group, the rate of postoperative contralateral hernias was only 2.3% in our series; therefore, the use of LPEC may be a form of overmedication in patients with contralateral asymptomatic PPV. However, as our study period was limited, the true incidence of contralateral hernias after OR is likely higher. Therefore, unnecessary closure of the PPV is thought to be less frequent.

Further investigations on the peculiarity of an asymptomatic PPV, which tends to cause metachronous hernias, may reduce the number of unnecessary ligations of contralateral PPV.

The limitation of this retrospective study was that the backgrounds of the two groups were different in terms of the sex ratio, age, and body weight. As the parents tended to choose LPEC at our institute, there was a selection bias for the procedures. A prospective controlled study might support our results showing the advantages of LPEC over OR.

Conclusions

In the LPEC group, no metachronous contralateral inguinal hernias were observed, and day surgery was safely performed in all cases. Incarcerated inguinal hernias and hydroceles were both safely treated by LPEC. The recurrence rate in the LPEC group was similar to that in the OR group. We therefore concluded that LPEC for inguinal hernias and hydroceles in children could be a safe and effective alternative to OR.