Male Pelvis

Intratesticular masses are considered malignant until proven otherwise, extratesticular mases are typically benign. Most malignant intratesticular tumors are of germ cell origin. Nongerm cell malignant tumors are sex cord-stromal tumors, lymphoma, leukemia, and mets. Lymphoma and leukemia can appear as focal hypo mases or produce diffuse involvement of testicle. Mets to testis is MC from melanoma, lung, kidneys, prostate

2 lab findings are helpful to differ from benign and malignant intratesticular tumors: hCG and AFP. Elevation in hCG levels is found with malignant tumors 60% of time. hCG is produced by the masses because they contain syncytiotrophoblastic cells. Elevated AFP is mostly associated with embryonal cell carcinoma, teratomas, and yolk sac tumors.

Other form of torsion is extravaginal torsion which occurs in the neonatal period or in utero and related to torsion of spermatic cord within inguinal canal. Torsion leads to testicular pain often during sleep. Torsed testis will be swollen and may be positioned higher in scrotum and have horizontal orientation. Pain may radiate to lower ABD and inguinal region, nausea, vomiting from intense pain. US depends on duration of time that's passed since first sign of symptoms.

Acute stage testis will appear enlarged and hypo hetero, no intratesticular vascularity with Doppler means completely torsed, enlarged epididymis, hydrocele, thickened scrotal wall. Some flow can be seen with lesser degrees of torsion, why we must compare flow of both testicles. Chronic torsion is torsion that has lasted more than 10days. Epididymis, testis, and spermatic cord will be enlarged and hetero, areas of necrosis within testis, hyperemic flow around testis

Torsion of the appendix testis is MC cause of acute scrotal pain in prepubertal boys. Appendix testis, epididymis, and vas are appendages of testis. These structures are embryological remnants of the mullerian, wolffian, and mesonephris duct. Appendix testis located between the head of epididymis and the superior pole of testis. Appendix epididymis is located at head of epididymis. Appendix vas is position between the body and tail of epididymis. Treated with pain meds and bed rest.

Appendages are not usually seen, but can be seen with hydrocele or other scrotal fluid collections. If seen, appear as a small oval projection of tissue. Instead of general testicular pain, they can present with focal testicular pain often localized to the superior pole of testis. Physician can inspect for "blue dot" sign which is the appearance of the torsed appendage as a blue dot just under the skin surface. Torsed on US is a small avascular hypo or hyper mass adjacent to superior pole of testis, scrotal wall thickening and hydrocele.

Epididymitis is the inflammation of the epididymis, MC cause of acute testicular pain in adults. Leukocytosis, fever, dysuria, urethral discharge, scrotal wall edema. Infections in the scrotum are ascending, meaning they start externally (urinary tract or prostate) and proceed into vas deferens, epidydimal tail, body, head, and testis (orchitis). Can also be caused by trauma. Infection of both epididymis and testis is called epididymo-orchitis. MC cause in younger men are chlamydia and gonorrhea.

Can be diffuse involving entire epididymis or focal with only one segment. On US, enlarged epididymis, hypo or hetero, increased vascularity with color. Orchitis will have increased intratesticular vascularity with low resistance patterns. Reactive hydrocele may appear, scrotal wall thickening. Chronic may appear as enlarged, hyper epididymis with calcifications

US done with a high frequency linear probe. Scrotal wall thickness is 2-8mm. Normal testicles are iso with a small amount of extratesticular fluid around each testicle. Normal mediastinum testis appears as an echo linear structure within the testicle in SAG or as a triangular structure in TRANS. Adult testicle measures 3-5cm in length, 2-4cm in width, 3cm A/P. Blood flow should be symmetric.

Each part of epididymis should be analyzed for masses, hyperemic flow, enlargement. Head measures 10-12mm and should be symmetric. Iso or more echo than testicle. Epdidymal changes can be seen after a vasectomy including enlargement and cystic areas.

Each testis is surrounded by a double layer of tissue called tunica vaginalis whish consists of a parietal and visceral covering. Hydrocele are MC see between these two layers. Beneath the layers of the tunica vaginalis, testis is intimately surrounded by a dense fibrous layer of tissue called the tunica albuginea. It extends posteriorly and enters each testicle to help form the mediastinum testis.

Epididymis is a coiled structure attached to the testicle and the posterior scrotal wall. Divided into Head, Body, and Tail. Head is superior to the upper pole of testis. Body is posterior to the testicle, Tail is inferior to the lower pole of testis. Epididymis stores sperm in order for them to mature, transports sperm into ductus (vas) deferens.

Endocrine function released directly into bloodstream: Produce testosterone, determines male characteristics

Exocrine function released through ducts: Produce sperm, permits reproduction

Seminoma is MC malignant neoplasm of testicles, a germ cell tumor found between 30-50 years. Found in patiens suffering from cryptorchidism. Unilateral and may replace entire testicle. Painless scrotal mass, hardening of testicle, elevated hCG levels. Intratesticular in location and appears as a solid, hypo mass, large ones can be hetero.

Nonseminomal tumors but are still germ cell tumors are choriocarcinoma, embryonal cell carcinoma, teratomas, yolk sac tumors. Sometimes a tumor can be comprised of a mix of these malignant tissues and referred to as mixed germ cell tumors.

Vascular Impotence is caused by vascular compromise to or within the penis that results in inability to obtain or maintain an erection. Caused by diabetic neuropathy which means the tiny vessels within the penis are damaged.

Normal Doppler shows an increase in arterial flow to the cavernosal arteries (systolic velocities normally 10-15cm/sec in flaccid state), venous outflow will become partially blocked and the diastolic flow will decrease. Diagnosis of venous incompetence can be made if the diastolic flow does not decrease as it normally should.

Testicles begin to develop in the upper ABD in the fetus near the kidneys and do not descend until the 4th week of gestation. By 28weeks, they descend into scrotum. They may become trapped anywhere along the way and consequently never completely descend, cryptorchidism. Testes function as both endocrine and exocrine glands. Spermatogenesis occurs within the seminiferous tubules that are found throughout each testicle. Tiny tubules converge into a structure called the rete testis located within the mediastinum testis.

Normal testicles are located within a sac of cutaneous tissue called scrotum. Scrotum is externally divided at the midline into two compartments by a structure called the median raphe. Internally it is divided by tunica dartos. Scrotum provided temp control for temp-sensitive sperm. Cremaster muscle, located within spermatic cord, alters the position of testicle within scrotum which aids in protection and temp control.

Adrenal Rests resemble a mass within the testicle and are associated with congenital adrenal hyperplasia or Cushing syndrome. Consist of ectopic adrenal tissue and caused by the migration of adrenal tissue with gonadal tissue during fetal development. Increased levels of adrenocorticotropic hormone.

On US appear as bilateral round hypo intratesticular masses near mediastinum testis MC.

Spermatocele is MC scrotal mass, a cyst often seen at head of epididymis. Composed of nonviable sperm, fat, cellular debris, lymphocytes. Painless, palpable mass. Tunica albuginea cysts are anywhere along the periphery of testicle and within tunica albuginea

On US looks like a cyst in the head of epididymis that may have layering debris. Epididymal cysts appear similar to spermatocele and can be seen anywhere along the epididymis.

Inguinal Hernia may consist of intestine or omentum. Persistent or intermittent scrotal swelling, ABD pain, blood in stool. Blood supply to bowel can be lost when an inguinal hernia becomes incarcerated and strangulated.

On US, a mass that has peristalsis and may contain air and fluid. Hydrocele can also be seen. Valsalva can help demonstrate peristalsing bowel. Fluid or air in loop of bowel can be seen.

Fracture of penis can occur with blunt sexual trauma, audible sound of a popping or cracking sound can be heard because typically one of the corpus cavernosa snaps under pressure. US may be used to further analyze the penis for soft tissue, urethral, and vascular damage even tho a diagnosis can be mad based on history and ecchymosis (subcutaneous spot of bleeding).

On US, area of hemorrhage within penis can have varying appearances depending on age or trauma. Most likely will see an irregular hypo or hyper defect at the site of rupture. Look at tunica albugenia for urethra because interruption of it can lead to voiding complications. Scar tissue can result in area of fracture.

Testicular Abscess is a result of untreated epididymo-orchitis. Fever, leukocytosis, painful swollen scrotum. Pyocele is a complex hydrocele that contains pus, seen in presence of a persistent scrotal infection or ruptured testicular abscess

On US, complex intratesticular mass with no flow centrally but increased flow around margins on color. Pyocele on US is a complex fluid collection within the scrotum that may contain septations and loculations.

Benign Prostatic Hypertrophy is the benign enlargement of the prostate. MC location is within transitional zone. Enlarged prostate can obstruct the flow of urine through urethra. Nocturia, increased urinary frequency, urinary urgency sensation, feeling of full bladder a lot, elevated PSA. May undergo transurethral resection of prostate to remove some hypertrophic prostatic tissue causing urinary complications.

On US, enlargement of inner gland that can lead to hypo area within prostate, calcifications, diffuse hetero, cystic changes

Testicle can be fractured as a result of trauma to scrotum. Rarely a fracture line can be seen, testicular margins may be unclear, and hematoma can be seen around testis. Hematocele is blood present within scrotum, most often caused by trauma to scrotum, recent pelvic surgery, scrotal surgery, torsion.

On US, hematocele is a complexfluid collection within scrotum that may contain septations and loculations. Clinical history is super important to differ from hematocele, pyocele, or complex hydrocele

Prostate Cancer, adenocarcinoma, is MC cancer in men. Blood in urine or semen, back or pelvic pain, hip or thigh pain, impotence, decrease in ejaculated fluid, elevated PSA. May cause enlargement of prostate. MC location of cancer is in peripheral zone.

On US, most will appear hypo to normal adjacent prostate tissue. Can mimic normal anatomy, prostatitis, BPH. May produce areas of hypervascularity. Biopsy warranted for definitive diagnosis.

A few mm of extratesticular fluid is normal. A simple fluid collection within the scrotum is called Hydrocele, found between the two layers of the tunica vaginalis and often displaces the testicle posteriorly. Can be idiopathic or reactive with of scrotal infections, testicular torsion, trauma, or tumors. Accompanied by scrotal wall thickening.

On US, simple fluid anterior to testis, scrotal wall thickening. Chronic hydroceles can have internal debris and septations.

Peyronie Disease is the buildup of fibrous plaque (scar tissue) and calcifications within the penis that results in a painful curvature. Impotence and poor arterial flow, painful erections, palpated scar tissue buildup

On US, the area will appear as thickening of the tunica albugenia, may contain areas of calcifications.

Cryptorchidism is undescended testis. Associated with infertility and increase risk for malignancy in involved testis. Seminoma is MC cancer found for this. Most often found just above the scrotum or within inguinal canal, but can also be in ABD. Surgical correction is called orchiopexy. Affected testis will not be palpable within scrotum

On US, undescended testis will be hypo to the normal one.

Prostate is retroperitoneal and produces and secretes alkaline fluid that constitutes 13-30% of the volume of semen.Located inferior to bladder, between symphysis pubis and rectum. Shaped like an inverted pyramid with base located superior and apex positioned inferior. Prostate is divided into 4 zones with prostatic urethra traveling through the center. Anterior fibromuscular stroma is an additional area and is located anterior to the prostatic urethra.

Paired seminal vesicles are located superior to the prostate and posterior to the base of bladder. They secrete an alkaline-based fluid and empty into the paired ejaculatory ducts. Ejaculatory ducts are formed by the union of the seminal vesicles and ductus deferens. The ducts travel through prostate and empty into urethra at an area called verumontanum.

Testicular Torsion occurs when the arterial blood supply to the testicle is cut off secondary to the twisting of testicular axis. Degree of torsion may vary. 360* torsion will result in blocked venous and arterial supply, will lead to ischemia within testis. Amount of ischemic damage is directly related to the degree of torsion. Occurs more often in adolescence, 12-18 years. A true surgical emergency, salvage rate ranges from 80% to 100% if patient is treated within 6hours of symptoms onset. Not salvageable after 24hours. Associated with trauma, strenuous exercise, sexual activity.

Patients predisposed to develop torsion have a condition known as "bell clapper" deformity, a congenital abnormality where the patient lacks the normal posterior fixation of the testis and epididymis to the scrotal wall. It is bilateral. It is a part of intravaginal torsion with is the MC form of torsion. Intravaginal torsion leave the testis who are not affixed to the scrotal wall permitted to migrate and twist freely within scrotum.

US of penis done with high frequency linear probe, supine position and penis resting upon the lower ABD when assessing flow. This position will cause dorsal surface of penis to be placed alongside the ABD exposing the ventral surface. US can be used to eval palpable lesions of penis like benign fibroma or malignant penile tumors.

Penis in TRANS: corpus spongiosum will be ventral. Paired corpus cavernosa will be dorsal. Spongiosum is elliptical and consists of medium to low level echoes. Cavernosa will be similar in echoes but will have an oval shape. Tunica albugenia is higly echo and seen separating and covering the corpora. Contained within each corpus cavernosum are the cavernosal arteries which can be seen with their bright walls and apparent blood flow with Doppler.

Zonal Anatomy

Peripheral Zone: Posterior lateral, apical gland. Largest zone, MC site for malignancy Central Zone: Base of prostate, 2nd largest zone Transitional Zone: On both sides of prox urethra. Site for BPH Periurethral glandular zone: Embedded in muscle of prox urethra. Smallest zone

Prostate can be seen TA or transrectally. TA is useful for measuring the overall size of prostate. Transrectal is used for biopsies and superior resolution. Patient is LLD with knees flexed toward chest or in lithotomy position for transrectal.

Prostate zones are homo and may be differentiated by visualizing landmarks such as prostatic urethra and ejaculatory ducts. May see benign calcifications and simple cysts within prostate.

On US, varicocele appears as a group of ane tubular structures located outside testis. Can be intratesticular in location too. To diagnose with color, Valsalva can be performed. When intraABD pressure is increased with Valsalva, the veins should fill with blood and become enlarged. Dilated veins measure >2mm.

Scrotal Pearl is an extratesticular calculus. Extremely echo, mobile, shadowing. An incidental finding and thought to be remnant of a formerly torsed and displaced testicular appendage.

Prostatitis is the inflammation of prostate. Hematospermia, painful ejaculation, perineal pain, dysuria. On US, enlarged hypo prostate with evidence of hyperemia on color.

Seminal Vesicle Cysts are ane or complex cystic structures in the area of the seminal vesicles, rare and either congenital or acquired. Asymptomatic but can be associated with Zinner syndrome (unilateral renal agenesis, ipsilateral seminal vesicle cyst, ejaculatory duct obstruction). Zinner syndrome symptoms are perirenal pain, recurrent prostatitis, painful ejaculation, infertility.

Intratesticular Cysts are rarely large enough to be palpable. Multiple small cysts can be seen along mediastinum testis. These cysts are small and clinically insignificant and result from tubular ectasia of rete testis. Thought to represent cystic dilation of rete testis. Epidermoid cysts can be seen too, appear to have a whorled or onion skin appearance

Testicular Microlithiasis appears as multiple echo foci with no shadowing in testis. Associated with malignancies, infertility, Klinefelter syndrome, cryptorchidism.

Ductus deferens is a tube that connects the epididymis to the seminal vesicles, it is also the structure that is surgically interrupted in a vasectomy. From vas deferens, sperm is transported to paired seminal vesicles which are posterior to the male bladder and above the prostate. These glands secrete fluid that helps produce semen. At their junction, the seminal vesicles and the vas deferens combine to create the ejaculatory duct.

The fluid is then passed through the prostatic urethra where additional fluid from the prostate is added. The bulbourethral gland, Cowper gland, secretes pre-ejaculate fluid that lubricates the penile urethra prior to ejaculation.

Varicocele is a dilated group of veins within scrotum, caused by incompetent or abnormal valves within the pampiniform plexus. Because of increased heat released by excess blood in scrotum, overheating of spermatozoa can occur. Overheating can influence the formation and mobility of sperm, its the MC cause of correctable infertility. Painless but if become large we see discomfort. Can also see varicocele with nut cracker syndrome

Two types: Primary and secondary. Primary are often found on the LT and are palpable during exam. LT more common cuz of the elevated vascular pressure or extended length or LT testicular vein and sharp angle at which it enters LT renal vein. RT sided is secondary, may be associated with hepatic mass, marked hydronephrosis, hepatomegaly, retroperitoneal neoplasm. If RT, additional ABD imaging required.

Penis in SAG: both spongiosum and cavernosa elongate, whereas the vascular channels can be seen stretching through the length of the cavernosa allowing for pulsed Doppler interrogation. Elongated penile urethra can be seen within corpus spongiosum.

US can aid in detection of strictures of penile urethra and vascular issues within penis. To look for strictures, patient should have full bladder and then void during exam. For vascular exam, penile flow is first analyzed in flaccid state and then injection of an erection inducing drug into the penis may be required to eval the vascularity of penis using color while penis is erect.

Penis is a primary sex organ, reproduction and urination. Penis is covered with skin and a dense fibrous tissue called Buck fascia. Inner penis is comprised of 3 cylindrical tissue components: single corpus spongiosum and paired corpus cavernosa. These are comprised of smooth muscle, erectile tissue, and vascular structures. Urethra is within corpus spongiosum and situated ventrally. Pared cavernosa are situated dorsally. Tunica albugenia surrounds corpus cavernosa and partially covers corpus spongiosum.

Vascular supply to penis begins at internal pudendal artery which is a tributary of the internal iliac artery. Internal pudendal arteries branch into the deep artery of the penis or penile artery and the bulbourethral artery. Deep artery of penis provides blood supply to corpus cavernosa. Bulbourethral artery supplies blood to the corpus spongiosum. Cavernosal arteries are located within cavernosa bilaterally. Sexual arousal will make the arteries within the penis engorged with blood, causing compression of adjacent veins and preventing venous drainage resulting in an erection.

Spermatic cord enters scrotum through the inguinal canal and contains the vascular supply and venous drainage for the testicle. Contains the testicular artery, pampiniform plexus, lymph nodes, nerves, cremaster muscles. Testicles receive most of blood supply by testicular arteries. Arteries emanate from the aorta just below the level of the renal arteries.

Venous drainage done through the pampiniform plexus which empties into testicular veins. RT testicular vein drains into IVC, LT testicular vein drains into the LT renal vein.