Chapter 23: Male pelvis

Cremasteric and deferential arteries accompany testicular artery within spermatic cord to supply...

-Cremasteric and deferential arteries accompany testicular artery within spermatic cord to supply extratesticular structures. -Have anastomoses with testicular artery and may provide some flow to testis --Cremasteric artery branches from inferior epigastric artery (branch of external iliac artery). -Provides flow to cremaster muscle and peritesticular tissue -Deferential artery arises from vesicle artery (branch of internal iliac artery). -Mainly supplies epididymis and vas deferens -Scrotal wall also supplied by branches of pudendal artery

Spermatic cord anatomy

-Normally seen superior to the posteromedial aspect of the testis Contains: -Vas deferens: Pampiniform plexus of veins -Testicular Artery: Genital branch of the genital femoral nerve -Cremasteric Artery: Testicular plexus of the sympathetic trunk -Deferential Artery: Lymphatic vessels Extends from the scrotum through the inguinal canal and internal inguinal rings to the pelvis Suspends the testis in the scrotum

Prostatic cyst

-Prostatic cyst is a rare disease of the prostate with 0.5% to 7.9% prevalence. Often asymptomatic and found accidentally with abdominal ultrasound, CT, or MRI. Some large prostatic cysts would have high level of serum prostate-specific antigen (PSA), and should be differentiated from other disorders such as prostatic neoplasm. -Occasionally, seminal vesicle cysts may be identified as anechoic or complex cystic structures in the area of the seminal vesicles. Seminal vesicle cysts are rare, they are said to be either congenital or acquired. Seminal vesicle cysts may be asymptomatic, but they can also be associated with Zinner syndrome. Zinner syndrome consists of unilateral renal agenesis, ipsilateral seminal vesicle cyst, and ejaculatory duct obstruction. Patients with Zinner syndrome present with perineal pain, recurrent prostatitis, painful ejaculation, and infertility.

Anatomical /Scan Position

Anatomical position is with penis in erect state. Drawing to the right is scanning on ventral surface.

INDICATIONS

Prostate Gland • Size and echo texture • Prostatitis (infection) • Detection of masses • Evaluation of benign prostatic hypertrophy (BPH) • Sonographic correlation of findings on a digital rectal examination • Sonographic correlation of evaluated serum prostatic specific antigen (PSA) • Evaluation of extracapsular spread of prostatic carcinoma • Evaluation of postoperative transurethral resection (TURP) • Ultrasound-guided biopsies of prostatic lesions Seminal Vesicles •Evaluation of size, symmetry, and echo texture •Ruling out presence of cysts or calculi •Inflammatory processes •Congenital anomalies

Sonographic appearance of SEMINAL VESICLES

SEMINAL VESICLES •Ultrasound examination of the seminal vesicles and prostate may be performed either by the transabdominal method through a distended urinary bladder, or by the transrectal approach. •The transabdominal method is used only to assess the size of the glands •Most pathology and the zones are not visualized transabdominally.

SEMINAL VESICLES ANATOMY

Seminal Vesicles The seminal vesicles are paired glands, encapsulated by connective tissue. Beneath the connective tissue is a thin layer of smooth muscle that surrounds the submucosa and mucous membrane. The seminal vesicles are convoluted, pouchlike structures emptying into the distal portion of the ductus (vas) deferens to form the ejaculatory ducts.

Epididymo-orchitis sono appearance

Sonographic Findings •Epididymitis appears as enlarged, hypoechoic gland. •If secondary hemorrhage has occurred, epididymis may contain focal hyperechoic areas. •Hyperemic flow confirmed with color Doppler •Normal epididymis shows little flow with color Doppler. •Amount of color flow signal should be compared between sides. •Affected side shows significantly more flow than asymptomatic epididymis. •Important to use same color Doppler settings when comparing amount of flow between sides •Hyperemic flow seen in epididymis and testis when both involved, but is restricted to epididymis only if testis is normal

Sonographic findings: acute scrotum

Sonographic findings associated with scrotal rupture: -Focal alteration of testicular parenchymal pattern -iinterruption of tunica albuginea -Irregular testicular contour -Scrotal wall thickening -Hematocele •Sonographic appearance of hematoceles varies with age. •Acute hematocele is echogenic with numerous, highly visible echoes that can be seen to float or move in real time. •With time, hematoceles show low-level echoes and develop fluid-fluid levels or septations. •Presence of hematocele does not confirm rupture.

Spectral Doppler waveforms obtained from the capsular, centripetal, or transmediastinal arteries show a....

Spectral Doppler waveforms obtained from the capsular, centripetal, or transmediastinal arteries show a low-resistance waveform pattern in normal individuals

Benign Testicular Masses

Tubular Ectasia of the Rete Testis: •Rete testis is located at hilum of testis where mediastinum resides. •Tubular ectasia of rete testis uncommon, benign condition •Associated with presence of a spermatocele, epididymal, or testicular cyst or other epididymal obstruction on same side as dilated tubules

Extratesticular Masses

Epididymal Cysts, Spermatoceles, and Tunica Albuginea Cysts Most scrotal cysts are extratesticular, found in tunica albuginea or epididymis. •Include spermatoceles, epididymal cysts, tunica albuginea cysts

Physiologic and Pathologic Conditions

Erectile Dysfunction (ED) •The inability to achieve and maintain an erection suitable for intercourse •Common condition - estimated to affect 1 in 10 men during their lifetime •Causes: •Vascular disease •Neurological disorders (nerves can be damaged from stroke, diabetes, multiple sclerosis, etc) •Psychological state • Trauma •Other causes such as chronic illness, post-surgical procedures, Peyronie's disease, and/or medications (diuretics, HTN meds, antihistamines, antidepressants, NSAIDs, recreational drugs)

Sonographic appearance

•The testes appear as smooth, medium-gray structures with a fine echotexture. •The mediastinum is often seen on ultrasound as a bright hyperechoic line coursing craniocaudal within the testis •The rete testis can sometimes be depicted with ultrasound. It appears as tiny tubules adjacent to the epididymal head and the testis mediastinum (arrow). -The normal epididymis usually appears as isoechoic or hypoechoic compared with the testis, although the echotexture is coarser. -The sonographic appearance of the gubernaculum testis or scrotal ligament is an echogenic band extending from the caudal end of the testis to the scrotal wall, seen in the presence of a hydrocele •Appendages of the testis and epididymis appear sonographically as echogenic protuberances superior to the testis and epididymis. Their shapes range from ovoid to stalk-like, sometimes forming a cyst. When stalked, the appendix is in danger of torsion. Color Doppler can occasionally detect blood flow inside testicular appendages.

Appendages

•There are four testicular appendages: the appendix testis (hydatid of Morgagni), the appendix epididymis, the vas aberrans (of Haller), and the paradidymis (Giraldes organ)

Varicocele

•A varicocele is an abnormal dilation of veins of pampiniform plexus (located within spermatic cord). •Primary varicoceles usually caused by incompetent venous valves within spermatic vein •More common on left •Secondary varicoceles are caused by increased pressure on spermatic vein. •May be result of renal hydronephrosis, abdominal mass, or liver cirrhosis. •Abdominal malignancy invading left renal vein may cause varicocele with noncompressible veins. •Sonographic evaluation of varicocele shows numerous tortuous tubes of varying sizes within spermatic cord near epididymal head. •Tubes may contain echoes that move with real-time imaging. •Varicoceles measure > 2 mm in diameter. •Tend to increase diameter in response to Valsalva maneuver

Peyronie's disease

•Abnormality of the erect penis such as a bend, curve, or hourglass-shaped narrowing •5% to 10% of men •Inflammation and scarring of the tunica albuginea •May be genetic or related to an injury

Epididymo-orchitis Associated findings:

•Associated findings: scrotal wall thickening and hydrocele •Hydroceles found around anterolateral aspect of testis •These may appear anechoic or contain low-level echoes. •Complex hydroceles may be associated with severe epididymitis and orchitis. •These will have thick septations and contain low-level echoes. •Severe cases: Pyocele may be present. •Pyocele occurs when pus fills space between layers of tunica vaginalis. •Usually contains internal septations, loculations, debris •Same appearance can occur following trauma or surgery. •Testicular infarction may occur in severe cases of orchitis. •Swollen testis confined within rigid tunica albuginea •Excessive swelling can cause obstruction to testicular blood supply. •Color Doppler: decreased or absent flow compared with contralateral testis •Decreased flow, spectral Doppler waveforms—high resistance with little or no diastolic flow

Blood flow disruption across surface of

•Blood flow disruption across surface of testis indicates rupture. •Epididymitis may result from trauma; color Doppler imaging can be used to identify associated increased vascularity in epididymis. •Torsion also associated with trauma •Color Doppler used to confirm absence of flow in testis with torsion.

Penile Trauma

•Can result from blunt or penetrating injury •Intracavernous hematomas •During erection, penile fracture can result from rupture of one or both of the corpora cavernosa

Choriocarcinoma

•Choriocarcinoma has a varied sonographic appearance because of mixed cell types. •Its appearance is determined by the dominant cell type, but it typically has irregular borders. •Teratomas may show dense foci that produce acoustic shadowing. They are normally heterogeneous but have well-defined borders. Teratomas are usually benign in children but malignant in adults. •Choriocarcinoma has a varied sonographic appearance because of mixed cell types. Its appearance is determined by the dominant cell type, but it typically has irregular borders. •Ultrasound imaging cannot differentiate malignant from benign masses. Neither color Doppler nor Doppler waveforms can reliably distinguish between flow patterns of benign and malignant tumors

penis

•Composed of three cylindrical masses of tissue. •two corpora cavernosa situated dorsolaterally •corpus spongiosum in the midventral region •contains the spongy urethra •The three corpora are bound and separated by the fibrous tissue called the tunica albuginea. •The three corpora are composed of smooth muscle and erectile tissue that enclose vascular cavities •Buck fascia, a thick, fibrous, loosely applied covering of skin that envelops the penis superficial to the tunica albuginea •The penis becomes enlarged and erect when engorged with venous blood.

Prostate pathology

•Cysts •Benign Prostatic Hyperplasia (BPH) •Prostate Carcinoma •Prostatitis •Enlarged seminal vesicles •Stones in the seminal vesicles, prostate or ejaculatory ducts

Testis Anatomy

•Each testis is covered by dense, white fibrous tissue called tunica albuginea •Tunica albuginea extends into posterior wall of testicle and forms mediastinum testis and interlobar septa (septa testis). •Mediastinum supports vessels and ducts coursing within testis •Septa of mediastinum radiate into each testis dividing it into > 250 to 400 conical lobules containing the seminiferous tubules. •Each lobule contains one to three convoluted seminiferous tubules •Seminiferous tubules are connected to straight tubules, which lead to the rete testis •Rete testis is located within mediastinum testis •Rete testis drains into head of epididymis through efferent ductules

Embryonal Cell Carcinoma

•Embryonal cell carcinoma is heterogeneous and less well circumscribed. It may contain areas of increased echogenicity resulting from calcification, hemorrhage, or fibrosis. •Cystic components are found in up to one third of embryonal cell carcinomas. •Embryonal cell tumors are more aggressive than seminomas, often invading the tunica albuginea and distorting the testicular contour.

Epididymo-orchitis

•Epididymo-orchitis is infection of epididymis and testis. •Most commonly results from spread of lower urinary tract infection via spermatic cord •Most common cause of acute scrotal pain in adults •Usually occurs secondary to epidiymitis

Patient Positioning and Scanning Protocol

•Explain procedure and preparation to patient; patient will get ready in private. •Supine position •Penis positioned on abdomen and covered with towel •Patient asked to place legs close together to provide support for scrotum •Rolled towel placed between thighs can support scrotum. •Apply generous amount of warmed gel to scrotum •High-frequency probes (10 to 14 MHz) •Bilateral exam, with asymptomatic side used as comparison for symptomatic side •Each testis scanned from superior to inferior •Apply generous amount of warmed gel to scrotum •High-frequency probes (10 to 14 MHz) •Bilateral exam, with asymptomatic side used as comparison for symptomatic side •Each testis scanned from superior to inferior •Size, echogenicity, and structure of each testis evaluated •Testicular parenchyma should be uniform with an equal echogenicity between sides.

Applications

•Follow-up of prior indeterminate scrotal ultrasound findings •Follow-up of postsurgical procedures (vasectomy, spermatocelectomy, hydrocelectomy, abscess drainage) •Evaluation for acute scrotal pain, including: testicular torsion, trauma, infectious or inflammatory scrotal disease •Presence of scrotal enlargement, swelling, asymmetry •Detection of peri-testicular fluid collections (hydrocele, hematocele) •Follow-up of patients with prior primary testicular neoplasm, leukemia, or lymphoma •Evaluation of palpable inguinal, intrascrotal, or testicular mass •Evaluation of varicocele •Evaluation of intrascrotal hernia' •Evaluation of abnormalities noted on other imaging studies (magnetic resonance imaging [MRI], computed tomography [CT], and positron emission tomography [PET]) •Localization of nonpalpable testes

Hematomas associated with....

•Hematomas associated with trauma may be large and cause displacement of the associated testis. •Hematomas appear as heterogeneous areas within scrotum. •Become more complex with time, developing cystic components •Hematomas may involve testis or epididymis, or they can be contained within scrotal wall. -Complex hematoma in a patient with hemophilia following scrotal trauma. Transverse ultrasound scan of both testes shows a large heterogeneous mass adjacent to the left testis. Color Doppler (not shown) demonstrated the mass to be avascular.

Congenital Anomalies in penis

•Hypospadias - opening of the urethra is on the underside of the penis instead of at the tip • Epispadias - opening of the urethra is on the top side of the penis instead of at the tip •Chordee - abnormal curve of penis at time of birth (not associated with Peyronie's disease) •Micropenis •Aphalia - extremely rare - congenital absence of penis

Sonographer Tips

•Image of Trans right and left testicle together for comparison in both gray scale and color Doppler •Perform Valsalva maneuver when varicocele suspected •Color Doppler with Valsalva/ Color Doppler after Relax •Sensitize color Doppler for slow flow when evaluating torsion.

Sonographic appearance of penis

•In the transverse scanning plane the corpus spongiosum will be seen in the midline, compressed by the transducer, and will appear elliptical in shape •Homogeneous texture composed of medium-level echoes. •Paired corpora cavernosa are posterior to the corpus spongiosum and appear symmetrically round or oval •Medium-level homogeneous echo texture covered by the highly echogenic tunica albuginea. •Echogenic plane dividing the two corpora cavernosa is an extension of the tunica albuginea called the septum penis •Centrally located within the corpora cavernosa are cavernosal arteries- echogenic walls and pulsations as seen in real time.

Prostate & SEMINAL VESICLES

•LOCATION: •Prostate Gland •inferior to the urinary bladder and surrounds the proximal urethra. •Posterior to the symphysis pubis •Separated posteriorly from the rectum by two layers of tissue called Denonvilliers fascia. •Laterally, the prostate is supported by the obturator internus and levator ani muscles. •Seminal Vesicles •Posterior to the urinary bladder •Superior to the prostate •Angles medially toward the apex of the bladder •Medial to the ureters.

Penile Ultrasound Technique

•Linear transducer (12-15 MHz) •Flaccid or erect (erection via injection of vasoactive drugs into penis) •Evaluate in transverse and longitudinal scan planes (possible lateral approach depending on condition being evaluated)

Lymphoma and Leukemia

•Malignant lymphoma: 1% to 7% of all testicular tumors; most common bilateral secondary testicular neoplasm affecting men > 60 years •Leukemia involvement of testicle is next most common secondary testicular neoplasm; most often found in children •Testicle may become enlarged; tumor bilateral or unilateral

Metastasis

•Metastasis to testicle is rare, normally occurring later in life •Primary tumor may originate from prostate or kidneys; less common sites include lung, pancreas, bladder, colon, thyroid, or melanoma. •Metastasis to testicle is bilateral, with multiple lesions found. Sonographic Findings •Solid hypoechoic mass •Hyperechoic •Mixture of both

Torsion

•Occurs as result of abnormal mobility of testis within scrotum •Bell clapper deformity occurs when tunica vaginalis completely surrounds testis, epididymis, distal spermatic cord, allowing them to move and rotate freely within scrotum. •The bell clapper congenital anatomical abnormality present in 12% of males •Testis and epididymis twist within scrotum, cutting off vascular supply within spermatic cord. •Up to 60% of torsion patients have anatomic anomaly on both sides. •Undescended testes are 10 times more likely than normal testes to be affected by torsion. •Compromises blood flow to testis, epididymis, and intrascrotal portion of spermatic cord •Venous flow affected first with occluded veins, causing swelling of scrotal structures on affected side •If torsion continues, arterial flow obstructed and testicular ischemia follows •Torsion of spermatic cord is surgical emergency. •If surgery performed within 5 to 6 hours of onset of pain, 80% to 100% of testes can be salvaged. •Between 6 and 12 hours salvage rate is 70%. •After 12 hours only 20% will be saved. •Torsion can occur at any age; peak incidence at age 14 •Presenting symptoms: sudden onset of scrotal pain with swelling on affected side Severe pain causes nausea and vomiting in many patients

Hydrocele, Pyocele, and Hematocele

•Potential space exists between visceral and parietal layers of tunica vaginalis. •This space is where a hydrocele, pyocele, or hematocele may develop. •Hydroceles contain serous fluid. •Are most common cause of painless scrotal swelling •May be idiopathic, but commonly associated with epididymo-orchitis and torsion •Pyoceles and hematoceles much less common than hydroceles •Pyocele is a collection of pus. •Occur with untreated infection or when an abscess ruptures into space between layers of tunica vaginalis •Hematoceles are collections of blood associated with trauma, surgery, neoplasms, or torsion.

Priapism

•Prolonged penile erection, with or without sexual stimulation •Best evaluated with color Doppler ultrasound Types: •Low flow (ischemic) priapism is medical emergency: Inadequate venous drainage results in hypoxia and tissue fibrosis and E.D. •Flow in the cavernous arteries is reduced or absent •Corpora cavernosa may show increased echogenicity due to tissue edema •Associated with: Sickle-cell disease • Drug use - recreational (cocaine) or other drugs (erectile agents, anticoagulants, antihypertensives, or antidepressants) • Malignancies (prostate, bladder, or penis) •High flow priapism - not emergent, lower risk of permanent sequelae •Associated w/blunt trauma to the perineum or penis w/cut to the cavernosa artery (most common) • Neurogenic causes due to spinal cord injury or cauda equina syndrome • Post shunting - after shunt procedure performed for low flow priapism •May observe normal or increased, turbulent blood flow in the cavernous arteries due to fistula formation

Prostate & SEMINAL VESICLES SIZE

•Prostate Gland •The prostate weighs approximately 20 g. •4 cm (<2 inches) wide, 3 cm (1.5 inches) in anteroposterior dimension, and 3.8 cm (1.5 inches) in length. •Unlike most other organs that atrophy with age, the prostate sometimes enlarges because of benign changes, infection, malignant tumors, or other causes. •Seminal Vesicles •Each seminal vesicle measures approximately 5 cm (2 inches) in length and less than 1 cm in diameter.

Prostate Carcinoma

•Prostate cancer, in the form of adenocarcinoma, is the most common cancer in men. •Patients with prostate cancer often present with blood in the urine or semen, back pain, pelvic pain, hip or thigh pain, impotence, and a decrease in the amount of ejaculated fluid. •Prostate cancer may cause an enlarged prostate that can be determined with a digital rectal examination. Patients may also have elevated PSA values. •Most common location for prostate cancer is within the peripheral zone. •It may produce areas of hypervascularity, and it can have variable sonographic appearances. •Most prostate cancers will appear hypoechoic to normal adjacent prostatic tissue. •It is important to note that the sonographic appearance of prostatic cancer can mimic normal anatomy, prostatitis, and BPH. Therefore, experience is needed to perform these procedures correctly. Biopsy is warranted for a definitive diagnosis.

Lab

•Prostate-specific antigen (PSA) is a protein produced by the prostate gland. Normal value <4ng/mL •PSA levels between 4 and 10 ng/mL (nanograms per milliliter) are considered to be suspicious.

Prostatitis

•Prostatitis is inflammation of the prostate. •Patients may complain of hematospermia, painful ejaculation, perineal pain, and dysuria. •Sonographically, prostatitis appears as an enlarged, more hypoechoic prostate with evidence of hyperemia upon color Doppler interrogation.

Anorchia

•Rare condition •Unilateral anorchia, or monorchidism, found in 4% of patients with nonpalpable testis •More common on left side; definitive diagnosis depends on surgical diagnosis •Causes: intrauterine testicular torsion or other forms of decreased vascular supply to testicle in utero

Vascular Supply

•Right and left testicular arteries arise from abdominal aorta below level of renal arteries. •Capsular arteries give rise to centripetal arteries, which course from testicular surface toward mediastinum along septa. •Before reaching the mediastinum, they curve backward forming recurrent rami (centrifugal arteries). •Branch further into arterioles and capillaries

Scrotum Anatomy

•Sac of cutaneous tissue that supports testicles •Externally divided into lateral portions by median ridge called the median raphe •Internally, scrotum is divided into sacs by a septum called the dartos or tunica dartos •Cremaster muscle surrounds each testicle and extends into abdomen over spermatic cord •Contraction of cremaster muscle performs the important function of regulating temperature of testicles •Tunica vaginalis consists of two layers derived from perineum lines inner walls of scrotum, covering each testis and epididymis: •Outer parietal layer that is closely attached to internal spermatic fascia •Inner visceral layer that is closely attached to testicle •Small bare area, which is posterior •At this site, testicle is against scrotal wall, preventing torsion. •Blood vessels, lymphatics, nerves, spermatic ducts travel through area. •Hydroceles form in space between layers of tunica vaginalis.

scrotal wall

•Scrotal Wall: •The scrotal wall is a thin layer of skin lined with smooth muscle tissue (dartos fascia). The skin contains more pigment than that of surrounding areas and has many sebaceous (oil-producing) glands and sweat glands, as well as some hair

Scrotal Hernia

•Scrotal hernias occur when bowel, omentum, or other structures herniate into scrotum. •Clinical diagnosis usually sufficient; sonography helpful in cases of equivocal findings •Bowel most commonly herniated structure, followed by omentum •Peristalsis of the bowel, seen with real-time imaging, confirms the diagnosis of a scrotal hernia.

Scrotal Pathology: Acute Scrotum

•Scrotal trauma presents challenge because scrotum often painful and swollen •Trauma may be result of MVA, athletic injury, direct blow to scrotum, or straddle injury •Determine if rupture present •If surgery performed within 72 hours following injury, up to 90% of testes can be saved, but only 45% can be saved after 72 hours. •Hydrocele and hematocele are both complications of trauma. •Hematoceles contain blood; found in advanced cases of epididymitis or orchitis Sonographic findings associated with scrotal rupture: -Focal alteration of testicular parenchymal pattern -iinterruption of tunica albuginea -Irregular testicular contour -Scrotal wall thickening -Hematocele •Sonographic appearance of hematoceles varies with age. •Acute hematocele is echogenic with numerous, highly visible echoes that can be seen to float or move in real time. •With time, hematoceles show low-level echoes and develop fluid-fluid levels or septations. •Presence of hematocele does not confirm rupture.

PROSTATE ANATOMY

•The peripheral zone is the largest, making up approximately 70% of the glandular prostate •lateral and posterior to the distal prostatic urethra. •The central zone forms about 20% of the glandular prostate, superior edge bordering the bladder and seminal vesicles. •The ejaculatory ducts course through this zone. •The transition zone accounts for only about 5% of the glandular prostate •has two lobes situated on the lateral aspects of the proximal prostatic urethra superior to the verumontanum •borders are the central zone posteriorly and laterally and the fibromuscular tissue anteriorly. •The tissue that lines the proximal prostatic urethra forms the periurethral glandular zone. •The prostate is surrounded by a thin capsule consisting of dense fibrous tissue and smooth muscle. This capsule connects with the muscle layers of the prostatic urethra. •The prostatic urethra is divided by the verumontanum (area near the center of the prostate) into proximal and distal segments. These proximal and distal segments form an angle of approximately 35 degrees at the verumontanum.

PHYSIOLOGY

•The production of sperm, or male germ cells, might be considered the most important function of the male reproductive system, but without the secretions of the accessory organs, the sperm could not survive to complete the process of reproduction. •Semen consists of sperm, the secretions of the prostate and seminal vesicles, and other glands associated with the male urogenital tract •The prostate gland and seminal vesicles secrete alkaline fluids that contribute to sperm viability. •The fluid the prostate produces and secretes is believed to neutralize the acid environment of the vagina, uterus, and fallopian tubes, where fertilization of the ovum takes place. •It constitutes between 13% and 33% of the volume of semen,. •The seminal vesicles secrete a viscous fluid rich in fructose. •It constitutes about 60% of the volume of semen. •Prostatic and seminal secretions are conveyed through numerous ducts to the prostatic urethra. •Carried outside the body through the penis via the distal urethra and finally exit through the external urethral orifice.

Prostate ANATOMY

•The prostate gland is shaped like a cone with a central core, the prostatic urethra. •The tip of the cone, or apex, is the inferior margin of the prostate. •The base of the gland is the superior aspect, which is inferior to the urinary bladder. •The prostate is perforated by the two ejaculatory ducts •enter the prostate at its posterior margin and course obliquely and anteriorly to join the prostatic urethra near the verumontanum (area close to the center of the prostate) •The prostate gland: •small anterior fibromuscular region, or stroma- located anterior to the prostatic urethra and is generally of less clinical significance because most pathology occurs in the glandular areas. •much larger posterior glandular region- divided into 4 zones: the peripheral zone, the central zone, the transition zone, and the periurethral glandular zone. The peripheral zone (P-zone) and the transition zone (T-zone) are the most discernable zones of the prostate.

Indications penis

Penile trauma Priapism Peyronie disease Erectile dysfunction Linear high-frequency transducers provide detailed sonographic anatomy of the penis.

A centripetal artery

A centripetal artery is seen coursing from the testicular capsule. Before reaching the mediastinum, it turns backward in a candy cane pattern, forming the recurrent rami.

Congenital Anomalies

Cryptorchidism (Undescended Testicle) •During fetal growth, testes first appear in retroperitoneum near kidneys. •Testes should descend into scrotum from inguinal canal shortly before birth or early in neonatal period.

Benign Testicular Masses: cyst

Cyst •Cysts more common in men over 40 years of age •Associated with extratesticular spermatoceles •Located near mediastinum •Single or multiple and of variable size

Malignant Testicular Masses: Germ Cell Tumors

Germ Cell Tumors •Testicular cancer is uncommon; accounts for only 1% of cancers in men •Is most common malignancy in men between ages of 15 and 35 •Is one of most curable forms of cancer •Occurs most frequently between ages of 20 and 34 •Undescended testes are 2.5 to 8 times more likely to develop cancer. •Symptoms: painless lump, testicular enlargement, or vague discomfort in scrotum •Primary goal: determine mass location; differentiate between cystic and solid composition •Extratesticular masses: usually benign •Intratesticular masses: more likely to be malignant •Testicular tumors categorized as germ cell and non-germ cell tumors •Germ cell tumors: associated with elevated level of human chorionic gonadotropin and alpha-fetoprotein •Approximately 95% of all testicular tumors are of germ cell type and highly malignant. •Non-germ cell tumors are generally benign. •Most common type of germ cell tumor is seminoma, followed by mixed embryonal cell tumors and teratocarcinomas •Sonographically, tumors appear as focal, hypoechoic masses. •Embryonal cell tumors more aggressive than seminomas •Choriocarcinoma has varied sonographic appearance because of mixed cell types. •Seminomas tend to be homogeneous, hypoechoic masses with a smooth border. •They do not often contain calcification or cystic components.

In approximately one-half of normal testes, a transmediastinal (or transtesticular) artery is....

In approximately one-half of normal testes, a transmediastinal (or transtesticular) artery is visualized coursing through the mediastinum toward the testicular capsule. A large vein is often identified adjacent to the artery On color Doppler, the transmediastinal artery will have a different color than the centripetal arteries because its flow is directed away from the mediastinum and toward the capsule. On reaching the testicular surface opposite the mediastinum, the transmediastinal artery courses along the capsule as capsular arteries

Benign Testicular Masses:Microlithiasis

Microlithiasis •Microcalcifications are < 3 mm. •Usually bilateral condition •Reported to have association with testicular malignancy; exact nature unknown •Microlithiasis has been associated with cryptorchidism, Klinefelter's syndrome, infertility, varicoceles, testicular atrophy, and male pseudohermaphroditism.

Relational anatomy

•Scrotum- suspended from the base of the male pelvis between the perineum and the penis •contains the testis, testicular appendages, epididymis, proximal portion of the ductus (vas) deferens, and the spermatic cord. •Gubernaculum testis- a mesenchymal band that anchors the fetal testis to the scrotal wall during testicular descent. In the adult, remnant is known as the scrotal ligament. Extends from the caudal end of the testis to the scrotal wall. •Appendix testis- commonly visualized when a hydrocele is present. The appendix testis is located at the upper pole of the testis and is the embryological remnant of the Mullerian duct. •Appendix epididymis- seen projecting from the head of the epididymis and is the embryological remnant of the Wolffian duct. •Epididymis- posterolateral to the testes, head- superolateral; body- posterolateral; tail- •Ductus (vas) deferens- courses superiorly to exit the scrotum through the inguinal canal. Inside the abdominal cavity, each ductus deferens courses along the lateral aspect of the urinary bladder and turns medially and posteriorly to connect with the seminal vesicles. •The spermatic cord- extends from the deep inguinal ring in the abdomen to the testis, descending vertically into the scrotum.

Stones in the seminal vesicles, prostate or ejaculatory ducts

•Seminal vesicle stones are small, solid calcifications that can form inside the vesicle due to inflammation, structural abnormalities, or reflux of urine back into the ejaculatory duct. •They are very rare, but can cause significant discomfort or bleeding, particularly during ejaculation. •Symptoms include pain, infection, or infertility. Treatment consists of removal of the seminal vesicle with adjuvant antibiotic therapy. •A doctor can remove the stone with a laser treatment or surgery

Sperm Pathway

•Seminiferous Tubules •Produce Sperm •Rete Testes •Efferent Ducts •Connect testis to epididymis •Epididymis •Vas Deferens •Connect epididymis to the ejaculatory duct •Ejaculatory Duct •Seminal Vesicle •ducts join Vas Deferens on each side to form the Ejaculatory Duct •Urethra •Path by which spermatozoa and urine pass exit the body

Sperm Granuloma

•Sperm granulomas occur as chronic inflammatory reaction to extravasation of spermatozoa. •Most frequently seen in patients with history of vasectomy •Sperm granuloma may be located anywhere within epididymis or vas deferens.

Sagittal Image

•Spermatic Cord Area •Epididymal head with superior testis •Long axis mid testis •Long axis mid testis with measurement •Medial long axis •Lateral long axis

Transverse Image

•Spermatic cord area •Epididymal head •Color Doppler of epididymal head •Superior testis •Mid testis •Mid testis with measurement •Color Doppler of mid testis •Spectral Doppler of artery •Spectral Doppler of vein •Inferior testis

Epididymal Cysts, Spermatoceles, and Tunica Albuginea Cysts

•Spermatoceles are cystic dilations of efferent ductules of epididymis: • Always located in epididymal head • Contain proteinaceous fluid and spermatozoa • May be seen more often following vasectomy •Epididymal cysts are small, clear cysts containing serous fluid located within the epididymis. •Epididymal cysts, spermatoceles, and tunica albuginea cysts are generally asymptomatic but may be palpable.

Scanning protocol

•TRUS TECHNIQUE •It is ideal to have a small amount of urine in the bladder. •The patient is typically placed in the left lateral decubitus position with the knees flexed toward the chest or in the lithotomy position for transrectal imaging of the prostate. •Ask the patient to try and relax and "bear down" to open the sphincter as the transducer is inserted slowly .Ensure the transducer has a latex free dedicated probe cover with plenty of gel. The highest frequency sector probe 7-12MHz should be used. •The scanning begins in the axial plane. The seminal vesicles are examined initially. As the probe is angled caudally the base of the prostate is seen. •Once the prostate is examined in its entirety in this plane the probe is turned 90degrees in a sagittal plane. The probe is angled from one side across to the other. •A volume is taken by measuring height x length in the sagittal plane and x width in the axial plane and multiply by 0.52. •Look for changes in the contours and echogenicity in each zone. •TRANSABDOMINAL TECHNIQUE •The patient lies supine. The patient should have a half full bladder . This can be achieved with drinking 500 mls of water 1 hr before the scan if possible is recommended. •The probe is angled approximately 30 degrees caudal using the bladder as a window. Slight compression to ensure the inferior portion of the prostate is not obscured by the shadow artifact from the base of the bladder. •

Testicular Arterial Branching

•Testicular artery •Capsular artery •Centripetal artery •Recurrent rami

Benign Prostatic Hyperplasia (BPH)

•The benign enlargement of the prostate gland is termed benign prostatic hyperplasia (BPH). •BPH is most often located within the transitional zone. •An enlarged prostate can obstruct the flow of urine through the urethra. Symptoms of BPH include nocturia, increased urinary frequency, a sense of urinary urgency, and a constant feeling of having a full bladder. •Patients will also have elevated PSA. •Patients with BPH may undergo transurethral resection of the prostate to remove some of the hypertrophic prostatic tissue causing urinary complications. •Sonographically, BPH will show an enlargement of the inner gland, and it can lead to hypoechoic areas within the prostate, calcifications, diffusely heterogeneous glan •d, and cystic changes.

Penis vascularity

•The blood supply to the penis and urethra is via the paired internal pudendal arteries, which are branches of the internal iliac arteries •Internal pudendal arteries divide into a deep artery of the penis and the bulbourethral artery. •The deep artery of the penis supplies the corpora cavernosa. •Branches of the dorsal artery and bulbourethral artery supply the corpus spongiosum, glans penis, and urethra. •The main veins of the penis are the superficial dorsal vein and the deep dorsal vein. The superficial dorsal vein is located outside Buck fascia, and the deep dorsal vein is beneath Buck fascia. The superficial and deep dorsal veins connect with the pudendal venous plexus, which drains the penis via the internal pudendal vein.

Epididymis Anatomy

•The epididymis is composed mostly of a single convoluted tube, the ductus epididymis, encapsulated by a serosal layer •Divided into the: •Head (globus major) -larger, superior portion -6 to 15 mm in width -mostly (10 to 15) efferent ductules from rete testis, which converge to form single duct in body and tail •Body -runs along the posterior aspect of the testis, contains the ductus epididymis •Tail (globus minor) -smaller, inferior portion, where ductus •Empties into ductus deferens (vas deferens)

Technical Considerations

•Transducer selection - High-frequency linear-array transducers •Color Doppler and power Doppler •Gain - The color gain control is used to amplify the reflected color Doppler signal •PRF - Scale/PRF—The PRF is the number of pulses transmitted in 1 second, affects the sensitivity of the system in displaying slow flow, sets the point at which color aliasing occurs (Nyquist limit). •Wall filter - The wall filter acts as an electronic eraser. Color echoes that fall below the filter cutoff do not appear on the image display., adjusted downward to enhance flow sensitivity., turned up to reduce flash artifact. On most ultrasound systems, the wall filter is automatically adjusted with the PRF. •Line density—number or density of scan lines contained within the color box, affects lateral resolution of the color display.. Frame rate becomes slower as line density is increased •Threshold or color/tissue priority— Color and power Doppler images are color overlays on top of an existing gray-scale image, allows the user to prioritize either gray scale or color •Packet size—The packet size is the number of sound pulses transmitted on each scan line within the color box, usually set between 8 and 20 pulses for each scan line, affects the signal-to-noise ratio, improving color sensitivity when more pulses are used..

Cryptorchidism

•Undescended testis may be located in abdomen, inguinal canal, or other ectopic location. •Testis usually found in inguinal canal; often palpable •Cryptorchidism is bilateral in 10% to 25% of cases. Sonographic Findings •Undescended testis: smaller and less echogenic than normal testis •Usually oval with homogeneous texture •Mediastinum rarely seen

Vascular Supply

•Venous drainage of the scrotum occurs through veins of pampiniform plexus. •Pampiniform plexus exits from mediastinum testis and courses in spermatic cord. • Pampiniform plexus converges into three sets of anastomotic veins: 1. Testicular 2. Deferential 3. Cremasteric •Right testicular vein drains into inferior vena cava; left testicular vein joins left renal vein. •Deferential vein drains into pelvic veins •Cremasteric vein drains into tributaries of epigastric and deep pudendal veins.

Testicular Ectopia

•Very rare condition •Ectopic testicle cannot be manipulated into correct path of descent. •Most common site for ectopic testicle to rest is superficial inguinal pouch. •Other sites include perineum, femoral canal, suprapubic area, penis, diaphragm, and other scrotal compartment.

Polyorchidism (Testicular Duplication)

•Very rare disorder; more common on left side (75%); bilateral in 5% of cases •Testicular duplication: Usually found in scrotum; has also been found in inguinal canal or retroperitoneum •Increased incidence: malignancy, cryptorchidism, inguinal hernia, torsion with polyorchidism •Duplicated testis: usually small; efferent spermatic system completely absent

Clinical Questions

•Was this patient referred because of palpable mass, scrotal pain, swollen scrotum, or other reason? •Ask patient to describe symptoms, including history, location, and duration of pain, fever. •Can he feel a mass? If so, ask patient to find lump. Place probe exactly over this location to examine site. •Did patient experience trauma? When did trauma occur? Describe what happened. •Vasectomy procedure? When? •Personal or family history of scrotal cancer or abnormality?