testicle.jpg (14559 bytes)



See  anatomy #1anatomy #2, anatomy#3 , anatomy#4, anatomy#5, anatomy#6

PET Scan#1 and #2, PET scan after radiation hereultrasound


The testes are 4 to 5 cm long, 3 cm wide, and 2.5 cm deep and have a volume of 30 mL. They are enclosed in a tough capsule comprising (1) the visceral tunica vaginalis; (2) tunica albuginea, with collagenous and smooth muscle elements; and (3) the tunica vasculosa. The epididymis attaches to the posterolateral aspect of the testis. Beneath it, the tunica albuginea projects inward to form the mediastinum testis, the point at which vessels and ducts traverse the testicular capsule. Septa radiate from the mediastinum to attach to the inner surface of the tunica albuginea to form 200 to 300 cone-shaped lobules, each of which contains one or more convoluted seminiferous tubules. Each tubule is U-shaped and has a stretched length of nearly 1 m. Interstitial (Leydig) cells lie in the loose tissue surrounding the tubules and are responsible for testosterone production. Toward the apices of the lobules, the seminiferous tubules become straight (tubuli recti) and enter the mediastinum testis to form an anastomosing network of tubules lined by flattened epithelium. This network, known as the rete testis, forms 12 to 20 efferent ductules and passes into the largest portion of the epididymis, the caput. Here, the efferent ductules enlarge, become more convoluted, and form conical lobules. The duct from each lobule drains into a single epididymal duct, which winds approximately 6 m within the fibrous sheath of the epididymis to form its body and tail. As the duct approaches the tail, it thickens and straightens to become the vas deferens.

The spermatic cord is composed of the vas deferens, testicular vessels, and spermatic fasciae


Testis and epididymis. A, One to three seminiferous tubules fill each compartment and drain into the rete testis in the mediastinum. Twelve to 20 efferent ductules become convoluted in the head of the epididymis and drain into a single coiled duct of the epididymis. The vas is convoluted in its first portion. B, Cross section of the testis, showing the mediastinum and septations continuous with the tunica albuginea. The parietal and visceral tunica vaginalis are confluent where the vessels and nerves enter the posterior aspect of the testis.