A new approach for pudendal nerve exposure and its clinical significance.

Analgesia of the pudendal nerve is used in patients undergoing gynecologic, obstetric and penile surgery. Stimulation techniques are used to determine the functions of the nerve. In these interventions, different landmarks are used to describe the localization of this nerve. Although some authors use perineal approaches, others prefer a transvaginal (rectal in males) approach. Knowledge regarding the anatomy of the pudendal nerve and its blockade allows an easy approach to the clinical problems like perineal neuralgia, neurogenic bladder dysfunction and penile implant operations. However, in the descriptions of these different approaches, there is no clear information regarding the depth of the nerve and the branches of the pudendal nerve that are blocked. The aim of the present study was to determine the depth and location of the pudendal nerve and, thus, describe certain and easily identified surface landmarks for clinical use. According to our examinations, the distance between the ischial tuberosity and the coccyx (the base of a triangle defined by the ischial tuberosity, coccyx and ischial spine) was 8.62 +/- 0.92 cm (range 6.74-9.77 cm). The distance between the ischial tuberosity and the ischial spine was 5.23 +/- 0.33 cm (range 4.76-5.81 cm) and the distance from the ischial spine to the coccyx was 5.42 +/- 0.52 cm (range 4.02-6.32 cm). Because the pudendal nerve intersected the distance between the posterior superior iliac spine and the ischial tuberosity, the distance between these two landmarks was also measured and found to be 13.31 +/- 0.91 cm (range 10.58-15.13 cm); the depth of the nerve was 4.14 +/- 0.83 cm (range 3.13-5.25 cm).

Three-dimensional structure of the modiolus. A computerized reconstruction study.

OBJECTIVE: Modiolus is a dense, compact, mobile fibromuscular structure, reachable by the dissection of buccolabial musculature. We undertook this study to provide detailed information about the macroscopic and microscopic anatomy of modiolus and its 3-dimensional (3-D) shape. METHODS: Fifteen micrometer thick serial sections were taken from the fixed cadaveric tissue samples and then stained with hematoxylin and eosin, and Massons' trichrome stain. Stained sections were photographed digitally and images were transferred to computer medium to perform 3-D reconstruction. The study was carried out in the dissection lab of the Anatomy Department of Hacettepe University, Ankara, Turkey between 2002 and 2003. RESULTS: The modiolus appears to be a tortuous, blunt conelike structure, extending vertically from the buccal mucosa to the dermis of the skin. The base of the cone is adjacent to the mucosa. CONCLUSION: As the structure has great clinical importance, and satisfactory complete 3-D analysis of the subject is not yet available; we believe that our study presenting the histological and 3-D description of the modiolus will be of great help to surgeons for satisfactory esthetic and functional results during surgical operations related to the oral commissure.

Bilateral additional renal arteries and an additional right renal vein associated with unrotated kidneys.

We report a rare anomaly of the kidneys and its vessels, which were found during the routine dissection of a 68-year-old male cadaver. The anomaly consisted of bilateral additional renal arteries originating from the abdominal aorta and an additional right renal vein accompanying the additional right renal artery. These anomalies were associated with unrotated kidneys with extrarenal calices and pelves. All the additional vessels were located posterior to the ureter with a close relationship to the ureteropelvic junction on the right side. Additional renal vessels arise as a result of the complicated development of kidneys and variations in the positional anatomy of the kidneys, and their vascular supply are of clinical importance.

Magnetic resonance imaging determination of the ventriculus terminalis.

We report a case of ventriculus terminalis, presenting with specific neurological symptoms including low back pain and bilateral sciatica. Magnetic resonance images showed a cystic lesion with regular margins localized in the lumbar enlargement of the spinal cord. The lesion was an oval shape with no internal septa. Its dimensions were 9.6 mm craniocaudally, 3.5 mm mediolaterally and 3.5 mm anteroposteriorly. Intralesional fluid had the same signal as cerebrospinal fluid in all magnetic resonance sequences. Pericystic spinal cord intensity was normal, and the cyst did not cause additional enlargement of the distal cord. During spinal cord evaluations, ventriculus terminalis should be kept in mind as a normal anatomic developmental phenomenon that can be seen on magnetic resonance images.