Chapter 28 scrotal and penile sonography

Capsular artery

A branch of the testicular artery that courses along the periphery of the testis in a layer known as the tunica vasculosa.

corpus spongiosum

A cylindrical mass of spongy tissue that surrounds the male urethra and is ventral to the two corpora cavernosa.

Gubernaculum testis

A mesenchymal band that anchors the fetal testis to the scrotal wall during testicular descent. In the adult, this atrophies and its remnant is known as the scrotal ligament. The scrotal ligament extends from the caudal end of the testis to the scrotal wall.

Gubernaculum testis

A mesenchymal band that anchors the fetal testis to the scrotal wall during testicular descent. In the adult, the gubernaculum atrophies and its remnant is known as the scrotal ligament.

Tunica vaginalis

A peritoneal sac composed of three layers that cover and surround the testis and epididymis except for a small posterior area.

Median raphe

A subcuataneous fibrous tissue or ridge that externally divides the two compartments of the scrotum. The fibrous tissue plate extends from the penile frenulum, along the penile shaft and scrotum, down toward the anus.

Scrotal wall

A thin layer of skin lined with smooth muscle tissue (dartos fascia) surrounding the scrotal sac.

Semen

A viscous whitish secretion of the male reproductive organs containing spermatozoa suspended in secretions from the prostate and seminal vesicles.

epididymis (plural: epididymides)

An elongated structure, posterolateral to the testis, divided anatomically into the head, body, and tail. It's primary function is the collection, maturation, and transport of spermatozoa via the ductus epididymis.

Testicular appendages measurements

Appendix testis 1-7mm in length Appendix epididymis 3-8mm in length

Transmediastinal artery

Branch of the testicular artery that emanates from the mediastinum testis. It pierces the testicular parenchyma, coursing in a direction opposite the centripetal arteries joining the capsular artery.

Centripetal artery

Branches of the capsular artery that course between the septa, supplying the testicular parenchyma.

Recurrent rami arteries

Branches of the centripetal arteries coursing back toward the capsular surface.

Spermatogenesis

Complex process of germ cell proliferation and differentiation which lead to the production and release of spermatozoa from the testis.

______________ of the cremaster muscle performs the important function of regulating the temperature of the testicles. Deep to the cremaster muscle is the innermost fascial layer of the ________, the internal spermatic fascia or infundibuliform fascia.

Contraction, scrotum

The cremaster muscle surrounds each testicle and performs what important function?

Contractions regulate internal temperatures of testicles

The __________ muscle is covered by the cremasteric fascia; this is continuous with the internal oblique fascia of the abdomen.

Cremaster

____________ muscle surrounds each testicle and extends into abdomen over spermatic cord. Contraction of _____________ muscle performs the important function of regulating temperature of testicles.

Cremaster

This structure is divided into globus major, corpus and globus minor:

Epididymis

_________________ runs along the superior-posterior aspect of the testes and drains into the ductus defrens and the base of the testis.

Epididymis

Ventral = _________ and dorsal = ________

Front, back

The cremaster muscle is covered by the cremasteric fascia; this is continuous with the __________ ________ __________ of the abdomen.

Internal oblique fascia

Tunica dartos

Internal septum of smooth muscle that divides the scrotum into two halves. Works in conjunction with cremaster muscle to regulate temperature.

____________, the scrotum is divided into sacs by a septum called the dartos or tunica dartos. The dartos contains superficial fascia and contractile tissue, which is also continuous with the subcutaneous tissue of the abdominal wall and is abundantly supplied by _______ blood vessels.

Internally, small

The scrotum is divided into _________portions by median ridge called the median raphe.

Lateral

Spermatic cord measurements

Linear structures measuring 2mm in AP diameter

Superior epididymal artery

Major blood supply to the epididymis

Testicular artery

Major blood supply to the testis.

Penis

Male sex organ, reaching its full size during puberty. In addition to its sexual function, the penis acts as a conduit for urine to leave the body.

The scrotum is divided into two compartments: externally by ________________ and internally by ________________

Median raphe; tunica dartos

This is a network of fibrous connective tissue continuous with the tunica albuginea that invaginates the posterior aspect of the testis and encloses the rete testis:

Mediastinum testis

Scrotum

Sac of cutaneous tissue that supports testicles

The pampiniform plexus begins in the _________ with a network of veins arising from the mediastinum testis. The pampiniform plexus becomes reduced to a single vein (testicular vein) as it ascends through the inguinal canal. The ______ testicular vein drains into the IVC at the level near the renal veins. The left testicular vein drains into the left _____ vein

Scrotum, right, renal

Ductus deferens course superiorly and enter into the pelvis through the inguinal canal. They continue superiorly lateral to the bladder to connect with the ___________ vesicles.

Seminal

Convoluted seminiferous tubules

Small channels located within the testis that produce and transport spermatozoa.

The __________ ______ consists of paired tubular structures surrounded by fascia, containing arteries, veins of the pampiniform plexus, ductus (vas) defrens, lymphatic vessels, and nerves. It extends from the deep inguinal ring in the abdomen to the testis, descending vertically into the scrotum.

Spermatic cord

Deferential artery

Supplies the epididymis and ductus (vas) deferens.

Cremasteric artery

Supplies the peri-tes-ticular tissues.

Scrotum

Suspended dual-chamber muscular pouch separated by the tunica dartos. Each chamber contains one of the two testes. It is suspended from the base of the male pelvis, between the perineal and the penis. Scrotal contents include the testis, epididymis, proximal portion of the ductus (vas) defrens, and spermatic cord.

The scrotum is

Suspended from base of male pelvis between the penis and the perineum.

The scrotum contains:

Testicles, Epididymis, ductus deferens

These are the four __________ __________: the appendix testis (hydration of morgagni), the appendix epididymis, the vas abberans (of haller), and the paradidymis (Giraldes organ).

Testicular appendages

This dense, white fibrous tissue covers the testis and forms the mediastinum testis and interlobar septa:

Tunica albugenia

Corpora cavernosa

Two cylindrical spongey masses of erectile tissue which contain most of the blood in the penis during an erection.

Normal measurements of ductus deferens

1.5-2.7 mm AP diameter <0.5 mm transverse diameter

Scrotal wall measurements

2-8mm in AP diameter

The septa of the mediastinum radiate into the testicle and separate into how many lobes?

200-300

The normal measurements for adult testicle is

3-5cm in length 2-3 cm in width 2-3 cm in AP Each testicle weights approx 12.5 to 19g, Testicular size and weight decrease with age.

Transmediastinal vein

Accompanies the transmediastinal artery, providing venous drainage from the testis.

The ________ contains superficial fascia and contractile tissue, which is also continuous with the subcutaneous tissue of the abdominal wall and is abundantly supplied by the small blood vessels.

Dartos

Tunica albugenia

Dense, white fibrous tissue that covers each testis and forms the mediastinum testis and interlobar septa.

The epididymis is composed mostly of this single convoluted tube:

Ductus epididymis

These four segments are the four segments of what? (1) scrotal, (2) suprascrotal, (3) prepubic (4) pelvic.

Ductus vas deferens

Appendix testis

Embryologic remnant of the paramesonephric duct (Mullerian duct).

Appendix epididymis

Embryologic remnant of the wolffian duct (mesophric duct).

The remnant of what structure is known as the scrotal ligament?

Gubernaculum

The normal measurements of the epididymis is

Head- 5-12 mm length, 10-12 mm AP diameter Body - 2-4mm AP diameter Tail- 2-5mm AP diameter

Testosterone

Hormone produced by the testes at the onset of puberty; causes growth in the male sex organs and development of secondary male sex characteristics such as body hair and voice deepening (endocrine function)

rete testis

Network of epithelial- lined channels embedded within the fibrous stroma of the mediastinum testis. They drain into the epididymis through 10-15 different ductules.

Mediastinum testes

Network of fibrous connective tissue continuous with the tunica albugenia, which invaginates the posterior aspect of the testis and encloses the rete testis. The mediastinum testis functions as a supporting system for arteries, veins, lymphatics, and seminiferous tubules.

Ejaculatory ducts

Paired ducts, each __________ ______ is formed by the union of the ductus deferens with the duct of the seminal vesicle. They pass through the prostate, and open into the urethra at the seminal colliculus.

Testes

Paired organs (male glands) of reproduction. They are classified as both endocrine and exocrine glands that produce both testosterone and sperm.

Ductus (vas) deferens

Paired thick-walled narrow muscular ducts that travel from the epididymis into the pelvis behind the urinary bladder. The ductus deferens transports spermatozoa from each epididymis to the ejaculatory ducts by PERISTALSIS.

Spermatic cord

Paired tubular structures in the male reproductive system that supports the testes in the scrotum. Each cord is sheathed in connective tissue and contains arteries, veins of the pampiniform plexus, lymphatics, autonomic nerves, and fibers of the cremaster muscle.

Venous drainage of the scrotum is via the

Pampiniform plexus

Outer layer of tunica vaginalis

Parietal layer, the inner lining of the scrotal wall that contains lymphatics for fluid absorption.

The corps cavernosa and corpus spongiosum are three cylindrical masses off tissue of what structure

Penis

Tunica vaginalis

Peritoneal sac composed of three layers that cover and surround the testis and epididymis except for a small posterior area. The visceral (inner) layer is a serious membrane that produces secretions. The cavum vaginale is the potential space between the visceral (inner) and parietal layer (outer) containing a few millimeters of fluid. The parietal (outer) layer is the inner lining of the scrotal wall that contains lymphatics for fluid absorption.

Just __________ to the dartos lies the external spermatic fascia, which is a continuation of the external oblique fascia of the abdominal wall.

Posterior

Just ___________ to the dartos lies the external spermatic fascia, which is a continuation of the external oblique fascia of the abdominal wall.

Posterior

What courses superiorly and exits the scrotum through the infuinal canal, and once inside the abdominal cavity, each one of these courses along the lateral aspect of the urinary bladder and turns medially and posteriorly to connect with the seminal vesicles.

The ductus vas deferens

What drains into the ductus vas deferens at the base of the testis?

The epididymis

Cavum vaginale

The posterior space between the visceral and parietal layer, containing a few millimeters of fluid.

Buck Fascia

Thick fascial layer that converts the two corpora cavernosa and the spongiosum.

Cremaster muscle

Thin layer of strained and smooth muscle that surrounds each testis and extends into the abdomen over the spermatic cord. Contraction and relaxation of the cremaster muscle is an important function in regulating the temperature of the testes.

Sonographically, normal testicular parenchyma is homogeneous and similar in appearance to:

Thyroid

The normal extrapelvic ductus (vas) deferens should measure less than 0.5 in ___________ diameter and 1.5 to 2.7 mm in ____ dimension

Transverse, AP

Pampiniform plexus

Venous network of approx 10 veins draining the testis and epididymis. The network surrounds the testicular artery in the spermatic cord and lies anterior to the ductus deferens. Each network coalesces to form the testicular (internal spermatic) veins. The ______________ _______ helps regulate the temperature of the testes by acting as a heat exchange mechanism to cool down the blood.

In the spermatic cord, the testicular artery is accompanied by the deferential artery ( branch of the __________ artery), and the cremasteric artery (branch of the __________ artery) The deferential artery supplies the ________ and the ductus vas deferens. Major blood supply to the epididymis is via the superior epididymal artery (branch of the testicular artery). The cremasteric artery supplies the peritesticular tissues.

Vesicular, epigastric, epididymis

Inner layer of tunica vaginalis

Visceral layer, a serious membrane that produces secretions.