The major advances in laparoscopic urologic surgery began with pediatric applications. The first laparoscopic urologic applications were in the localization of an impalpable unde–scended testicle. This technique became the definitive diagnostic and first operative step in management of this condition. Laparoscopy offered a 97% chance of finding a testicle or proving its absence. Recent advances in en–doscopic and accessory instrumentation have allowed the urologist to expand the role of la–paroscopy in the pediatric population. In some respects, children may be better suited for laparoscopic procedures than adults because of their decreased intra-abdomi–nal and retroperitoneal fat.

Currently, laparoscopy has been used in pediatric urology for:

1. Localization and eval–uation of impalpable undescended testicles
2. Gonadal examination and biopsy in patients with intersex disorders
3. Orchiectomy for undescended testicles
4. Diagnosis and treat–ment of pediatric inguinal hernias
5. Staged orchiopexy
6. Spermatic vein ligation in pa–tients with a varicocele
7. Retarded testicular growth
8. Nephrectomy
9. Nephro–ureterectomy
10. Pyleoplasty.

There are several important factors to consider when operating in the pediatric patient. First, there is a relatively short distance between the anterior abdominal wall and the great vessels. Thus, the margin for error in pediatric laparoscopy is inversely proportional to the age and size of the patient. Trocars and needles must not be passed too deeply to avoid vascular injury. Also, the child has a thinner abdominal fascia requiring less pressure to introduce the Veress needle and trocars into the abdomen. In addition to this, the pelvic anatomy differs in infants and young children. A large portion of the bladder is located out–side the bony pelvis. Prompt decompression of the bladder with a catheter before a Veress needle is essential to avoid a bladder perforation. Also, much less car–bon dioxide gas is required in the child, as the peritoneal cavity is small compared to that of an adult.

Children's dimensions are well-suited to laparoscopy. Landmarks are readily identifiable and palpable. For example, the bifurcation of the great vessel as well as the sacral promon–tory are usually easily felt. In addition, abdominal or pelvic masses are easily detected in most children.

LAPAROSCOPY FOR THE IMPALPABLE UNDESCENDED TESTICLE OR INTERSEX EVALUATION

Diagnostic Laparoscopy is indicated for patients with non palpable testis or an intersex problem. After a thor–ough physical examination has been accomplished, laparoscopy may be used and has a di–rect impact on any subsequent surgical procedure. For example, if the testis is absent and blind ending vessels are seen, an open exploration can be avoided. If, however, a testicle is present, the precise location with laparoscopy determines the optimal incision for any open procedure. If an orchiopexy is considered, the first part of a Fowler-Stephens procedure may be performed laparoscopi–cally. This results in minimal manipulation of the testicle. Furthermore, if the testicle is dysplastic, it may be removed laparoscopically.

Operative Technique

After placement of the Veress needle into the abdominal cavity, insufflation is begun. During insufflation, the intra-abdominal pressure should rises slowly at a rate of 0.5 litre/minute in pediatric patient and the abdomen of the child should become diffusely tympanic. Most children require car–bon dioxide volumes between 0.5 and 2.0 liters. Following proper insufflation, the Veress needle is removed and trocars are placed. When placing trocars, it is important not to ad–vance these too deeply in the abdomen in order to avoid injury to the underlying bowel and vascular structures. After placement of the umbilical l0mm trocar, the laparoscope is introduced into the abdominal cavity. Interperitoneal pressures of 10mm Hg suffice for di–agnostic procedures. For more complex procedures, pressures of 12 to 15mm Hg are de–sirable and allow for better maintenance of an adequate pneumoperitoneum.

The abdomen is inspected in the midline between the obliterated umbili–cal arteries is the urachus. On the pelvic side wall, the spermatic vessels may be seen coursing towards the internal inguinal ring. If a testicle is palpable in the scrotum, the vas deferens on that side is usually quite obvious as it travel through the inguinal ring to the retrovesical recess. In most children, the external iliac vessels are easily seen as there is minimal extraperitoneal pelvic fat. The cord structures may be further identified by placing slight traction on the spermatic cord and pulling down on the descended testicle. This will cause a dimpling of the peritoneum and the spermatic vessels are easily seen near the in–ternal ring. Indirect hernias and patent processus vaginalis may also be noted.

After inspecting the side of the normal testicle, attention is focused on the side with the undescended, impalpable gonad. If a patent processus vaginalis is noted, gonads or remnants may be present distally. However, absence of a patent processus does not elim–inate the possibility of a gonadal remnant in the inguinal area. If the cord structures are seen extending through the inguinal ring with a patent proces–sus, the testicle may not be visible initially. Gentle pressure on the external canal will push a canalicular testicle back through the internal ring. Although Canalicular testes may be managed with a standard, open inguinal orchidopexy. The bene–fit of laparoscopy in these cases is to assess cord length and testicular mobility This will have a direct impact on the planned surgical approach.

During diagnostic laparoscopy an atraumatic grasper may be placed under direct vision to allow ma–nipulation of bowel loops. In most cases, only two ports are needed. If the testicular absence is suspected the inspection is accomplished by direct observation of blind ending spermatic ves–sels. Often the vas may end blindly at the same site or nearby, but it is the determination of the spermatic vessels that is pathognomonic for a nonexistent gonad. In those patients with a blind ending vas, it is important that inspection be carried as high up along the side wall towards the lower pole of the kidney as possible. If blind ending vessels are not seen, close observation of this area is necessary. Laparoscopic inspection of the lower pole of the kidney suffices to rule out rare, high-placed gonads. Inspection of the abdomi–nal cavity is not necessary in these patients whose spermatic vessels are blind-ending, in order to declare testicular absence.

In patients with an intersex condition biopsy should be taken from dysplastic gonad or it may be re–moved. A biopsy may be accomplished with a biopsy needle passed directly into the abdomen under laparoscopic control. If an orchiectomy is to be performed, the dysplastic gonad is isolated. The spermatic vessels are identified and clipped. The vessels are then cut and the stump inspected to insure adequate hemostasis. If a testicle is seen, it may be brought down into the scrotum with a Fowler-Stephens procedure. When performing a Fowler-Stephens procedure, the technique is similar to removing a testicle. Once the testicle is clearly identified, the dissection is limited to the cephalad sur–face of the testicle to identify the spermatic artery.

This dissection will not disturb the ves–sels of the vas deferens, which will form the major blood supply of the testicle. Initially the spermatic artery is identified and a window is created around the vessel. A clip applier is placed through a l0mm trocar site that has access to the spermatic artery. Two clips are placed proximal and two clips distally on the artery. The artery is then cut with scissors. In some circumstances, electrocautery may be used to coagulate the spermatic artery before the vessel is cut. This maneuver is the first step of a Fowler-Stephens proce–dure and can be accomplished with minimal amount of interabdominal dissection. During next stage of surgery the testicle is brought down into the scrotum on its enhanced blood supply. This two-stage procedure has been successful not only in patients with long vasal loops but also in patients with high abdominal testis and short vas deferens.

In some patients, an impalpable testicle may be proximal to the internal ring in such a way that its vessels allow adequate mobilization. In these instances, a single-stage orchi–dopexy may be performed. This is done laparoscopically using three ports. Two 5mm ports are placed in a lateral position and one l0mm trocar in the midline. A peritoneal incision lateral to the spermatic cord is made. The spermatic cord is rolled medially and el–evated from the retroperitoneal tissues. The gubernaculums is opened adjacent to the patent processus vaginalis. The anterior peritoneum of the gubernaculum is then opened laterally. If a loop of the vas deferens is identified, it is reflected in the cephalad direction. The testi–cle is grasped and the gubernacular attachments are cauterized and divided. The vas defer–ens is then mobilized by opening the peritoneum medially. With adequate dissection, the testicle will be able to be moved around the pelvis.

A small transverse skin incision is created at the base of the hemiscrotum and carried down through Dartos fascia. A subcutaneous pouch is created and the testicle is pulled down into the pouch. A small clamp is passed through the canal that has been de–veloped into the peritoneal cavity. The gubernacular re–flections of the lower pole of the testis can then be grasped and the testicle brought down into the hemiscrotum without tension. The testicle is se–cured in the Dartos pouch and the skin incision is closed. The Fo–ley catheter and nasogastric tube may be removed in the operating room. Patients are usu–ally given oral antibiotics for 24 hours and discharged from the hospital on the same day. Diets are advanced as tolerated.

OTHER LAPAROSCOPIC PEDIATRIC PROCEDURES

Many other pediatric conditions may be treated using the laparoscope. If Nephrectomy in the pediatric patient is planned, a retroperitoneal approach may have a distinct ad–vantage in certain older children. Laparoscopic pyeloplasty for ureteropelvic junction ob–struction has also been performed with very encouraging result. Currently, studies are being done to evaluate the effectiveness of this technique. Bladder auto augmentation, another innova–tive procedure, is performed by incising the detrusor muscle to increase the capacity of the bladder. Other laparoscopic pediatric procedures such as hernia repairs and partial nephrectomy also have been performed. In pediatric laparoscopy, the greatest risk of complications occurs at the time of access. Some surgeon have eliminated this risk by using the Hasson trocar technique rather than the Veress needle technique. In children, the peritoneal space is small and the surgeon should be familiar with working in a smaller environment. The safety of pediatric laparoscopy is well established and more and more pediatric surgeons are now a days switching over to laparoscopy.