Anatomy and blood supply of the lower four cranial and cervical nerves: relevance to surgical neck dissection.

This study is a continuation of previous work searching for possible anatomic reasons to explain variable and usually unpredictable postoperative pain and dysfunction after the same nerve losses with similar neck dissection operations. The study consisted of dissections of 19 deceased unpreserved elderly subjects arterially injected with dyed latex. Of the 19 subjects, 14 had brain stem and cervical spinal cord dissections, and all had neck dissections. The findings suggested two possible anatomic reasons for the pain and dysfunction: (i) The intracranial anatomy of the lower four cranial nerves, the glossopharyngeal (IX), the vagus (X), the spinal accessory (XI), and the hypoglossal (XII), was just as variable as the previously reported peripheral spinal accessory nerve plexus; and (ii) Both the intracranial and neck dissections indicated that the blood supply to the lower four cranial and cervical nerves, particularly to the brachial plexus, could be impaired by atherosclerosis and/or neuroforaminal impingement or operative loss. This loss of blood supply theoretically could result in ischemia as another possible cause of postoperative pain and dysfunction. It is concluded that because of the potential importance of each nerve and vessel, often unknown at operation, it is very important to spare as many of them as possible to avoid subsequent painful impairment.

[Pectineal ligament of Cooper. Micromorphometric study]. / Ligament pectinéal de Cooper. Etude micromorphométrique.

The pectineal ligament is used in surgery as a support element in the treatment of groin hernias and female urinary stress incontinence. The question is to determine the anatomical characters that account for its strength. Three complementary approaches have been considered: an anatomical dissection study established the origin of the different fibers the ligament is composed of; a morphometric study determined the areas where the ligament is the thickest; and microscopic anatomy clearly showed the arrangement of the fibers. The pectineal ligament continues the near-by fibers fibrous elements, notably thanks to its ends. The latter are significantly thicker. At microscopic level, the regular layout of the pectineal ligament fibers accounts for its resistance.

New experimental model of ureteropelvic junction obstruction allowing easy access for percutaneous surgery.

To assess the usefulness of an experimental model of ureteropelvic junction (UPJ) obstruction designed to facilitate subsequent percutaneous surgery, a right UPJ obstruction was created in 10 pigs by an open retroperitoneal surgical approach. With the pig in the left lateral decubitus position, a 0.038-inch Terumo guidewire was inserted via a 1-cm longitudinal upper-third ureterotomy and advanced up and down so as to bridge the UPJ from the flank to the urogenital opening. A UPJ obstruction was then induced by securing two 2-0 chromic gut ties, separated by an interval of 1 cm, over the Terumo guidewire and a 6F ureteral catheter, which was removed immediately after this procedure. After closure of the ureterotomy, the kidney was anchored horizontally to the muscle wall, and the Terumo guidewire was coiled subcutaneously in the flank and fixed to the urogenital opening. Each pig developed marked hydronephrosis, diagnosed by ultrasonography, after a mean interval of 8.3 days. Retrograde ureteropyelography confirmed this pronounced dilation of the right collecting system above a tight UPJ stricture (mean length 1.17 cm). Subsequent percutaneous access to the UPJ over the Terumo guidewire in the lateral decubitus position was facilitated by the almost-horizontal plane of dilation (mean operating time 14 minutes). Pathologic examination of the UPJ revealed mild periureteral fibrosis, but the muscle layer and urothelium remained normal. We have developed a reliable and reproducible model of secondary UPJ obstruction especially designed for percutaneous surgery. This model should provide a better understanding of current endoscopic techniques such as endopyelotomy and could help to promote new treatment concepts such as percutaneous endoscopic pyeloplasty.

Anatomy of the prostatic nerves.

The entire prostate of a 10 year old boy was cut with a microtome in to 4300 serial slices. The nerves were stained using a monoclonal antibody called anti PS 100. All information was recorded using a computer reconstruction programme. The prostatic nerve supply is very abundant. The nerve fibers of the cranial prostate (central zone) follow a pathway parallel to the anterior surface of the seminal vesicles going towards the caudal prostate. The periurethral zone is widely innervated by nerves arising from the periphery. The caudal prostate also contains many nerve fibers of variable size. We identified many nerve fibers along the anterior surface of the seminal vesicles and surrounding the lateral aspect of the prostatic capsule. They penetrate the capsule and the whole circumference of the caudal prostate. The prostatic capsule is covered by numerous nerve fibers and ganglia, which form a true periprostatic nerve network. The urethra is supplied by numerous thick fibers of more than 30 microns in diameter.