Abdomen Anatomy: Testes & Epididymis PDF

Anatomy of Abdomen Lecture 7 Testes & epididymis Sajjad Abdulaziz A 3rd-staged medical student at Al-Nahrain University  Objectives Testes. Interior of testes. Epididymis & its parts. Appendix...

Anatomy of Abdomen Lecture 7 Testes & epididymis Sajjad Abdulaziz A 3rd-staged medical student at Al-Nahrain University  Objectives Testes. Interior of testes. Epididymis & its parts. Appendix testis & appendix epididymis. Tunica vaginalis. Arterial supply & venous & lymphatic drainage of testes & epididymis. Innervation of testes. Hydrocele of testes / hydrocele of spermatic cord. Hematocele of testes. Torsion of spermatic cord. Varicocele. Testes 🔵 The testes (testicles) : - are paired ovoid (have upper and lower poles) reproductive glands. - are suspended in the scrotum by the spermatic cords (the left testis usually suspended (hanging) more inferiorly than the right testis). - produce sperms (spermatozoa) and the testosterone hormone. - have a tough fibrous outer surface called the tunica albuginea. Interior of the testes 🔵 The tunica albuginea thickens into a ridge on its internal, posterior aspect as the mediastinum testis. 🔵 From this internal ridge, fibrous septa extend inward dividing the testis into 250 lobules. 🔵 Each lobule contains 2-3 seminiferous tubules (are minute but long and highly coiled tubules in which the sperms are produced). 🔵 These tubules become straight tubules posteriorly and anastomose forming the rete testis (is a network of canals in the mediastinum of the testis). 🔵 From the rete testis, about 12-14 efferent ductules arise, pierce the tunica albuginea and pass into the head of the epididymis. Epididymis Straight tubules Appendix testis & appendix epididymis 🔵 There is a small appendage (called the appendix testis) on the upper pole of the testis. It is a remnant of the paramesonephric (Müllerian) duct. 🔵 There is another small appendage (called the appendix epididymis) on the top of the epididymis. It is a remnant of mesonephric duct. 🔴 The appendix testis and the appendix epididymis may undergo torsion (become twisted), causing acute pain. Tunica vaginalis 🔵 Each testis with its corresponding epididymis are invaginated anteriorly into a double-layered peritoneal serous sac (called the tunica vaginalis). 🔵 The tunica vaginalis represents the closed-off distal part of the embryonic processus vaginalis. 🔵 The tunica vaginalis composed of parietal & visceral layers with a cavity in between. 🔵 The visceral layer is closely applied to the testis, the epididymis. 🔵 The parietal layer lines the internal spermatic fascia. 🔵 The cavity of the tunica vaginalis contains a small amount of fluid which enables the testis to move freely in the scrotum. 🔵 Sinus of the epididymis : - is a slit-like recess in the cavity of the tunica vaginalis. - lies between the body of epididymis and the posterolateral surface of the testis. 🔵 To reach the testis from outside the body, these layers must be removed in order. - skin of scrotum. - dartos fascia. - external spermatic fascia. - cremasteric muscle and fascia. - internal spermatic fascia. - parietal layer of tunica vaginalis. - visceral layer of tunica vaginalis. Arterial supply of the testes & epididymis Venous drainage of the testes & epididymis Lymphatic drainage of the testes & epididymis 🔵 Free communication occurs between the lymphatics on either side. 🔵 The lymphatic vessels from of the testes and epididymis follows the testicular veins and drain into the right and left lumbar (caval/aortic) lymph nodes and pre-aortic lymph nodes. 🔴 Malignant disease from the testis may spread to the lymph nodes at the root of the neck. Varicocele 🔵 A varicocele is an abnormal enlargement of the pampiniform venous plexus in the scrotum. 🔵 A varicocele may be noticed (when the man is standing or straining) as soft lumps, usually above the testicle. 🔵 Palpating a varicocele can be likened to feeling a bag of worms. 🔵 Varicocele occurs predominantly on the left side because : - the acute angle at which the right testicular vein enters the IVC is more favourable to flow than the nearly right angle at which the left testicular vein enters the left renal vein, making it more susceptible to obstruction or reversal of flow. - the left renal vein may compressed between the abdominal aorta and superior mesenteric artery (nutcracker syndrome). 🔵 Varicoceles may also occur on right or left side as a result of defective valves in the testicular vein. Thank you