TESTES, SCROTUM and PROSTATE

The Scrotum, Testis, Epididymis Introduction/ General Information A. Scrotum 1. “Medial pendant pouch of loose skin & superficial fascia” (Gray’s) 2. Raphe (Gr. “seam” or “suture”): Superficial division between compartments 3. Left side lower than right

4. Dartos muscle (lies in fascia) a. Temperature sensitive response Introduction, continued … 4. Dartos muscle (lies in fascia) a. Temperature sensitive response hot = relax cold = contract b. Right & left compartments c. Testis, epididymis, tunica vaginalis in each

Scrotum, Testes, Epididymis, con’t… B. Testis 1. Suspended in scrotum by spermatic cord 2. 4 - 5 cm long 3. Weigh 10.5 - 14 grams 3. Oval

Anatomy of the Male Pelvis

4. Descend from abdominal cavity prior to birth Testis, continued … 4. Descend from abdominal cavity prior to birth a. As they descend they collect various coverings b. Layers of abdominal wall

3. Located on posterior & superior margins of testes Scrotum, Testis, Epididymis, continued … Epididymis 1. Highly coiled tube 2. 15 - 16 feet long 3. Located on posterior & superior margins of testes 4. Elongated, flattened structures

5. Partially covered by visceral layer of the tunica vaginalis Epididymis, continued … 5. Partially covered by visceral layer of the tunica vaginalis 6. Structurally divided into a head, body, and tail 7. Tail is continuous with vas deferens 8. Head receives efferent ductules from testes

Testicular Anatomy

Appendages 1. Appendix of the testis Testicular Anatomy, con’t… Appendages 1. Appendix of the testis a. Lies beneath head of Epididymis b. Remnant of the Mullerian duct (gives rise to uterine tubes, uterus in female) c. May be referred to as “Hydatid of Morgagni”

Testicular Anatomy, con’t… Appendix of Testis Appendix of Testis

2. Appendix of the Epididymis a. Attached to head of Epididymis Appendages, continued … 2. Appendix of the Epididymis a. Attached to head of Epididymis b. Detatched, modified efferent duct c. Remnant of mesonephric duct (primitive Epididymis, vas deferens)

Appendages, continued … Appendix of Epididymis Appendix of Epididymis

A. Superficial inguinal rings (of inguinal canal) Detailed Anatomy A. Superficial inguinal rings (of inguinal canal) 1. Triangular openings in abdominal muscle 2. Superior & lateral to pubic tubercles 3. House contents of spermatic cord

Anatomy of the Spermatic Cord Deep inguinal ring Superficial inguinal ring

1. Layers, beginning superficially a. Superficial fascia Detailed Anatomy, continued … B. Scrotum 1. Layers, beginning superficially a. Superficial fascia 1. skin & tunica dartos b. Colle’s fascia 1. membranous layer of superficial fascia 2. continuous over penis & scrotum

c. External spermatic fascia: derived from Scrotum, continued … c. External spermatic fascia: derived from 1. transversus abdominis 2. internal oblique muscle d. Cremasteric fascia: derived from 2. internal oblique muscle e. Internal spermatic fascia: derived from transversalis muscle

Detailed Anatomy, Layers of the Scrotum, continued … Superficial (Dartos) Fascia Colle’s Fascia External Spermatic Fascia Cremasteric Fascia Internal Spermatic Fascia Parietal Layer, Tunica Vaginalis Visceral Layer, Tunica Vaginalis Tunica Albuginea Skin

f. Layers of peritoneum have serous fluid between to allow mobility Scrotum, continued … f. Layers of peritoneum have serous fluid between to allow mobility 1. Parietal layer of tunica vaginalis a. Lines scrotal sacs 2. Visceral layer of tunica vaginalis a. covers testis b. part of epididymis

2. Testis (superficial to deep) a. Visceral layer of tunica vaginalis Scrotum, detailed anatomy, continued … 2. Testis (superficial to deep) a. Visceral layer of tunica vaginalis b. Tunica albuginea (capsule of testis) c. Seminiferous tubules d. Mediastinum testis (aka: hilum of testis) - Efferent Ductules - Rete testis (network of tubules)

Testicular Anatomy (Netter, Plate 371) Efferent Ductules Rete Testis Seminiferous Tubules Mediastinum Testis Tunica Albuginea

1. Coverings from abdominal wall 2. Each spermatic cord contains: Detailed Anatomy, continued … C. Spermatic Cord 1. Coverings from abdominal wall 2. Each spermatic cord contains: a. Ductus (vas) deferens b. Deferential artery & vein c. Sympathetic nervous system fibers

d. Spermatic/testicular artery & vein Spermatic Cord, detailed anatomy, continued … d. Spermatic/testicular artery & vein e. Pampiniform plexus (network of veins) f. Lymph vessels g. Vaginal ligament 1. Obliterated diverticulum 2. From Processus vaginalis (later)

Anatomy of the Spermatic Cord

1. Testicular (internal spermatic) artery III. Vessels & Nerves A. Arteries 1. Testicular (internal spermatic) artery a. Branches directly from abdominal aorta b. Inferior to renal artery c. Passes deep to peritoneum

d. Travels through inguinal canal to reach testis Arteries, continued … d. Travels through inguinal canal to reach testis e. Testicular migration follows this path Testicular Artery

a. Branch of Testicular Artery Arteries, continued … 2. Cremasteric artery a. Branch of Testicular Artery b. Supplies Ureter & Cremaster muscle

a. Branch of internal pudendal artery Arteries, continued … 3. Perineal artery a. Branch of internal pudendal artery b. Gives rise to posterior scrotal artery c. Supplies perineum & external genitalia

4. Superior Vesical artery a. From fetal hypogastric artery Arteries, continued … 4. Superior Vesical artery a. From fetal hypogastric artery b. Gives rise to deferential artery c. Anastomosis with testicular artery d. Supplies upper portion of urinary bladder

Arteries of the Male Reproductive Tract Fetal hypogastric artery Superior vesical artery

Arteries of the Reproductive Tract

1. Pampiniform plexus (major venous drainage) Vessels & Nerves, con’t … B. Veins 1. Pampiniform plexus (major venous drainage) a. Approximately a dozen b. form a network c. Become larger, converge approaching inguinal canal.

a. From convergence of pampiniform plexus veins Veins, continued … 2. Testicular vein a. From convergence of pampiniform plexus veins b Enters IVC on right c. Enters renal vein on left

C. Testicular Lymphatics 1. Follow arteries, veins Vessels & nerves, continued … C. Testicular Lymphatics 1. Follow arteries, veins 2. End in lumbar nodes 3. From scrotum, penis, prepuce: terminate in superficial inguinal nodes 4. From testis, spermatic cord: drain into external iliac & lumbar nodes

1. Ilioinguinal nerve (L-1) a. Into inguinal canal Vessels & Nerves, continued … D. Nerves 1. Ilioinguinal nerve (L-1) a. Into inguinal canal b. Through superficial inguinal ring c. Supplies skin of upper scrotum & medial thigh d. via anterior scrotal nerve

a. Genital branch supplies cremaster muscle Nerves, continued … 2. Genitofemoral nerve a. Genital branch supplies cremaster muscle b. Receives branch of iliohypogastric nerve c. Femoral branch supplies medial portion of thigh d. Cremasteric reflex (scratch medial thigh, causes scrotum to contract)

IV. Embryology/Descent of Testis A. Development 1. Scrotal swellings appear at ~ 7 weeks in lower abdominal wall 2. Processus Vaginalis: a. evagination of peritoneum b. push into scrotal swellings 3. Layers of abdominal muscle, fascia 4. Give rise to inguinal canal

4. Testes develop on posterior abdominal wall a. on urogenital ridge Embryonic Development, continued … 4. Testes develop on posterior abdominal wall a. on urogenital ridge b. near kidneys 5. Gubernaculum testis: ligament that connects testis & epididymis to inside of scrotum

Formation of Processus Vaginalis Embryonic Development Formation of Processus Vaginalis Testis Gubernaculum

7. Testis are retroperitoneal a. travel inferiorly Development, continued … 6. As scrotum grows it pulls testes, epididymis, and gubernaculum posterior and inferior 7. Testis are retroperitoneal a. travel inferiorly b. exit through inguinal canal c. into scrotum

Descent begins at ~3 months Descent of Testes Descent begins at ~3 months Adult Configuration

8. Gubernaculum testis becomes scrotal ligament Development, continued … 8. Gubernaculum testis becomes scrotal ligament 9. Testis pulls spermatic cord along 10. Processus vaginalis pinches off a. forms tunica vaginalis b. Visceral: covers testis & epididymis c. Parietal: folds back, leaves hilus uncovered

Descent of Testes Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

B. Descent (by way of inguinal canal) 1. Inguinal ligament Descent of Testes, con’t…. B. Descent (by way of inguinal canal) 1. Inguinal ligament a. Formed from exterior oblique aponeurosis b. Extends from anterior superior iliac spine to pubic tubercle c. Forms base of inguinal canal d. Some fibers bend laterally & posteriorly to form pectineal ligament e. Attached to bone

2. Deep inguinal ring (deep to anterior superior iliac spine) Descent, continued … 2. Deep inguinal ring (deep to anterior superior iliac spine) 3. External spermatic fascia: derived from what muscle?? 4. Cremasteric fascia: formed from what muscle??

Spermatic and Cremasteric Fasciae

5. Superficial inguinal ring a. Subcutaneous opening of inguinal canal Descent, continued … 5. Superficial inguinal ring a. Subcutaneous opening of inguinal canal b. Surrounds contents & coverings of spermatic cord c. Located superior to inguinal ligament & lateral to pubic tubercle

Anatomy of the Spermatic Cord Deep inguinal ring Superficial inguinal ring

a. Begin descent at ~ 3rd month Descent, continued … 6. Testes develop in lumbar region between peritoneum & fascia of transversalis muscle a. Begin descent at ~ 3rd month b. Have descended from posterior abdominal wall to deep inguinal ring at ~ 7th month

Descent, continued … c. Testes are preceded by Processus Vaginalis (aka: peritoneal diverticulum) d. Collect fascia, muscles: these give rise to layers covering testes e. Reach superficial inguinal ring by ~8th month f. Testes are usually in scrotum by birth

Formation of Processus Vaginalis Embryonic Development Formation of Processus Vaginalis Testis Gubernaculum

Descent of Testes Fused Processus Vaginalis Descent begins at ~3 months Adult Configuration

1. Indirect (oblique) inguinal hernia V. Anomalies/Diseases Hernias 1. Indirect (oblique) inguinal hernia a. Results when processus vaginalis fails to close at birth b. May allow for loops of small bowel, greater omentum to enter processus vaginalis & scrotum c. causing bowel obstruction

Hernias, continued … 2. Peritoneal cyst a. Results from persistent connection between peritoneal cavity & tunica vaginalis (due to partial closure of tunica vaginalis) b. A cyst forms in the “connection” space c. May not be noticeable at birth; later, accumulation of fluid may form a Hydrocoele

Normal vs. Abnormal Scrotum Note: Hydrocele Testicular torsion Normal Testis

Testicular Microlithiasis, Hydrocele

a. Opening in fascia covering femoral canal Hernias, continued … 3. Femoral hernia: a. Opening in fascia covering femoral canal b. May allow small bowel to slide through, causing obstruction

4. Direct inguinal hernia Hernias, continued … 4. Direct inguinal hernia a. Arises from weakness in abdominal wall near rectus abdominis muscle b. Area is a common site of herniation c. Loops of small bowel may pass through opening

5. Congenital inguinal hernia Hernias, continued … 5. Congenital inguinal hernia a. Result from failure of Processus Vaginalis to close prior to birth b. Allows head of Epididymis to remain in deep inguinal ring

Anomalies of the Processus Vaginalis Partially Patent Normal Completely Patent Deep and Superficial Rings in Infancy Herniation

1. Expansion of pampiniform plexus 2. Usually seen on left (why??) Anomalies/Diseases, continued … B. Varicocoele 1. Expansion of pampiniform plexus 2. Usually seen on left (why??) 3. Can be palpated a. feels like a “bag of worms”

Pampiniform Plexus

Cryptorchidism (occurs in 4% live births in U.S.) Anomalies/Diseases, continued … Cryptorchidism (occurs in 4% live births in U.S.) 1. Failure of testis to descend by birth 2. Unilateral = less potent; Bilateral = sterile 3. Abdomen: sterile 4. Inguinal canal may contain testes 5. More often affected by malignancy (20x) 6. Often descend in the first year of life

D. Ectopic testis (out of place) 1. Migrated from normal course Anomalies/Diseases, continued … D. Ectopic testis (out of place) 1. Migrated from normal course 2. Found in thigh or perineum E. Hematocoele: 1. accumulation of blood 2. in tunica vaginalis from trauma

1. Due to abdominal venous compression Anomalies/Diseases, continued … Lymph Edema 1. Due to abdominal venous compression 2. Abdominal aortic aneurysm (AAA) 3. Intra-abdominal tumor 4. Cirrhosis with ascites 5. Filariasis a. From filarial worms in drinking water b. Can cause elephantiasis

H. Testicular tumor 2. Most arise from primordial germ cells Anomalies/Diseases, continued … H. Testicular tumor 1. Generally have unknown etiology 2. Most arise from primordial germ cells 3. Usual symptom: scrotal mass of increasing size 4. May be associated with pain 5. Any firm mass or cystic mass in scrotum should be checked

Testicular Tumor: Doppler U/S

6. Biopsy is primary diagnostic tool a. Chest x-ray, IVP Testicular Tumor, continued … 6. Biopsy is primary diagnostic tool a. Chest x-ray, IVP b. To check for direct/indirect metastasis 7. Treatment a. Surgical excision if tumor is benign b. Castration with chemotherapy & radiation if malignant

Endodermal Sinus and Yolk Sac Tumor Doppler U/S Tumor of Testis

PROSTATE GLAND

Introduction/General Information Attached inferiorly to urinary bladder by ligaments Posterior to pubic symphysis Surrounds superior portion of urethra Anterior to rectum (palpation, ultrasound) Conical shape

1. 4 cm trans x 2 cm A/P x 3 cm Sup/Inf G. Lightly encapsulated Introduction, Prostate Gland, continued … F. Walnut sized 1. 4 cm trans x 2 cm A/P x 3 cm Sup/Inf G. Lightly encapsulated 1. Fibrous connective tissue 2. Smooth muscle 3. Capsule extends into lobes

II. Prostate Gland: Detailed Anatomy A. Largest male accessory gland B. Located in subperitoneal compartment (between pelvic diaphragm & peritoneum) Prostate Gland, Mid-sagittal Section

Prostate Gland: Detailed Anatomy C. Enclosed in fascial sheath (aka: prostatic sheath) 1. Inferiorly, sheath is continuous with superior fascia of urogenital diaphragm 2. Posteriorly, sheath forms part of retrovesical septum

1. Fibrous portion contacts gland Prostate Gland: Detailed Anatomy D. Double Capsule 1. Fibrous portion contacts gland 2. External capsule formed by pelvic fascia 3. Venous plexus lies between

Male Reproductive System, Posterior View

E. Conical shape with base (sup), apex (inf), four surfaces Detailed Anatomy, contined … E. Conical shape with base (sup), apex (inf), four surfaces 1. Surfaces: posterior, anterior, right & left inferolateral 2. Base (aka: vesicular surface): superior a. Attached to neck of urinary bladder b. Prostatic urethra enters middle of base close to anterior surface

Prostate Anatomy Prostatic Urethra

a. Rests on superior fascia of urogenital diaphragm muscle Detailed Anatomy, contined … 3. Apex: inferior a. Rests on superior fascia of urogenital diaphragm muscle b. Associated with sphincter urethrae c. Contacts medial margins of levator ani muscles

Detailed Anatomy, contined … 4. Posterior surface: triangular, flat 5. Anterior surface: narrow, convex 6. Inferiorolateral surfaces a. Meet with anterior surface b. Rest on levator ani fascia above urogenital diaphragm

1. Divisions are arbitrary, indistinct 2. Usually divided into Detailed Anatomy, contined … F. Lobes of the Prostate 1. Divisions are arbitrary, indistinct 2. Usually divided into a. two lateral lobes b. one median lobe c. anterior and posterior lobes

Lobes of the Prostate, continued … 3. Median lobe a. Lies posterior and superior to prostatic utricle and ejaculatory ducts b. May project into urinary bladder c. Utricle lies within lobe 1. Vestigial remains of uterine homolog 2. Sometimes called “uterus masculinis”

a. Comprise the greatest mass of the gland Lobes of the Prostate, continued … 4. Lateral lobes a. Comprise the greatest mass of the gland b. Contain most secretory tissue c. Are continuous posteriorly 5. Glandular tissue with varying amounts of fibrous tissue

Lobes of the Prostate, continued … Prostate Gland in situ

Detailed Anatomy, continued … G. Blood & lymph 1. Arteries derived from: a. Internal pudendal artery b. Inferior vesical artery c. Middle rectal artery

Blood & Lymph, continued … 2. Veins a. Form venous plexus b. Drain into internal iliac veins c. Communicate with vesical & vertebral venous plexuses

Blood & Lymph, continued … 3. Lymphatics a. Most terminate in internal iliac & sacral nodes (unable to palpate) b. From posterior: to external iliac nodes (unable to palpate)

1. 30 - 50 different glandular elements a. Serous glands Detailed Anatomy, contined … Glandular tissue 1. 30 - 50 different glandular elements a. Serous glands b. 20 - 30 ducts empty into prostatic urethra 2. Most are posterior & lateral to urethra

a. Thin, milky, alkaline (looks like skim milk) Blood & Lymph, continued … 3. Prostatic secretions a. Thin, milky, alkaline (looks like skim milk) b. Discharged at ejaculation c. Make up ~ 1/3 of semen

Prostate size changes 1. Small at birth 2. Enlarges at puberty Detailed Anatomy, continued … Prostate size changes 1. Small at birth 2. Enlarges at puberty 3. Maximum at about 13 4. Progressive enlargement after 40 5. Sometimes: undergoes atrophy

III. Pathology 1. Affects ~90% of men >50 A. Benign prostatic hypertrophy (BPH): 1. Affects ~90% of men >50

2. Common cause of urethral obstruction: causes a. Nocturia b. Dysuria BPH, continued … 2. Common cause of urethral obstruction: causes a. Nocturia b. Dysuria c. Urgency d. Back-pressure effects e. Complete obstruction can occur

B. Prostate cancer 1. Most common cancer in males Pathology, continued … B. Prostate cancer 1. Most common cancer in males

2. Metastasizes via blood (hematogenous) or lymph (lymphogenous) Pathology, continued … 2. Metastasizes via blood (hematogenous) or lymph (lymphogenous) 3. Common sites: vertebrae, pelvis a. Via venous plexus surrounding prostate b. Bone or direct metastasis most common

Prostate Cancer: Routes of Metastasis

Prostatitis (accompanied by cystitis) 1. Inflammation of gland Pathology, continued … Prostatitis (accompanied by cystitis) 1. Inflammation of gland 2. Gland enlarges, becomes tender 3. Causes: gonorrhea? Other UTI’s? STD’s? 4. May require antibiotics, massage 5. Symptoms: chills, painful urination, back pain

Prostatic concretions (aka: corpora amylacea [starch bodies]) Pathology, continued … Prostatic concretions (aka: corpora amylacea [starch bodies]) 1. Small spherical or ellipsoid bodies 2. Number increases with age 3. May become calcified as male ages 4. May simulate carcinoma

Digital Rectal Exam

E. Rarely, prostatic abscesses develop Pathology, continued … E. Rarely, prostatic abscesses develop 1. Frequently caused by gonorrhea 2. May rupture through to rectum, bladder, perineum 3. Other causes: a. Urethritis b. Epididymitis