The anatomical layers of inguinal region in children are hard to recognize, while the hernia sac (peritoneum) is thin. As for traditional high ligation of hernia sac, the sac, sometimes difficult to find, is highly vulnerable to tear during dissection. This is more likely to cause tissue injury to iliohypogastric and ilioinguinal nerves, spermatic vessels, vas deferens, as well as postoperative complications like scrotal edema or hematoma, iatrogenic cryptorchidism, testicular atrophy, etc. even affecting their fertility function in adulthood. Sometimes the ligation of hernia sac fails to reach high, or the ligated tissue is too much to keep tight, either of which could result in a small hernia sac again, leading to increased recurrence. In addition, there are also risks such as being difficult to detect occult hernia. By contrast, laparoscopic surgery does not damage the anatomical structure of inguinal region, and due to the amplification effect of laparoscopy plus the expansion of hernia sac caused by pneumoperitoneum, the internal ring is easy to find, and the inferior epigastric vessels, spermatic vessels, vas deferens can be more clearly identified, thereby reducing the injury to vessels, nerves, vas deferens and the incidence of related complications.
In clinical practice, we tried implementing the ambulatory surgery mode for modified single-port laparoscopic method, and achieved promising results. Its specific characteristics and advantages are as follows: (1) With its suitable size and particular curve and slope on the tip, the epidural puncture needle is conducive to jacking the peritoneum during procedure, and can be advanced beneath peritoneum by adjusting the angle, which make it preferable to the traditional hernia needle for separating the extraperitoneal space.[16–18] (2) In terms of guidewire selection, the green-.025" guidewire is of appropriate thickness, hardness and good compliance (Fig. 3). By one puncture to the abdominal wall, the entry and exit tunnels are kept on the same path under its guidance, avoiding the postoperative pain caused by multiple punctures and the ligation at different layer. (3) A small amount of normal saline or air is injected into the extraperitoneal space through the needle during procedure, and with the aid of saline or air separation, the vas deferens and vessels can be separated from the peritoneum more easily, avoiding iatrogenic ligation. Extruding air and fluid before tightening the suture also reduces the postoperative inguinal and scrotal edema. (4) In terms of suture selection for hernia ring ligation, 3 − 0 Prolene thread has higher strength and is less prone to suture knot reaction than absorbable or silk thread.
However, the single-port laparoscopic method also has a certain degree of risks or complications.[19–21] Such laparoscopic ligation of hernia ring requires relatively high level of the operator skill.[22] Sometimes in single-port method, the instrument needle cannot successfully puncture to the extraperitoneal space and bypass the vas deferens and spermatic cord at one time, and may need repeated punctures, which is easy to cause bleeding, resulting in blurred anatomical structure of the vas deferens and spermatic cord region, thereby increasing the possible injury to vas deferens, spermatic or iliac vessels and leading to complications like extraperitoneal hematoma, testicular atrophy, etc. If the hernia sac is too thickened or edematous to recognize the vas deferens and pampiniform spermatic vessels, it would be likely to puncture and injure the vas deferens or spermatic vessels, leading to bleeding. Especially when the instrument needle reaches the branch of inferior epigastric vessels on the inner side of internal ring, it is not easy to control the needle direction, which may injure epigastric vessels once too deep, resulting in hematoma at the internal ring. In addition, there is also the risk of postoperative hydrocele or recurrence due to a neglect of peritoneal gap.[23–24]
In order to avoid injury, reduce related complications and ensure treatment outcome, attention should be paid to the following: (1) Preoperative urination is required to avoid interference with intraoperative exposure and maneuver or accidental injury to the bladder. (2) Blunt dissection of peritoneum using spoon-like epidural needle is not easy to injure adjacent vessels and cause hematoma. Especially, it is safer to push aside the vessels with the aid of saline or air separation. (3) When separating the medial peritoneum of internal ring, the puncture needle should be advanced right beneath peritoneum, but should neither go through the spermatic cord and vas deferens so as not to ligate them accidentally, nor excessively jack the sac into the abdominal cavity so as to avoid ligation at sac body rather than sac neck, which increases the possibility of hernia recurrence. (4) When threading for suture of the medial and lateral half circles, the inlet and outlet of needle should be the same point and single path, so that the hernia sac neck is tightly closed without leaving a gap, which prevents recurrence or hydrocele to the greatest extent. (5) Before tightening the suture, reset the testis and extrude the air from hernia sac to avoid iatrogenic cryptorchidism and postoperative emphysema of hernia sac. Use non-absorbable thread such as Prolene for ligation, and knot firmly, which could help in reducing hernia recurrence.
In conclusion, this project investigates the modified single-port laparoscopic surgery in the treatment for inguinal hernia in children. Using epidural puncture needle and green guidewire, with the aid of saline or air separation, the hernia ring can be accurately ligated by Prolene suture outside the peritoneum just through transumbilical single-port laparoscopy. It has the advantages of minimal invasiveness, enhanced recovery, less complications and recurrence, thus should be recommended in clinical application.