The testes are two glandular organs with ovoid shape,
flattened on the sides,
approximately 5 cm long,
3 anteroposterior diameter and 2.5 cm wide; its surface is smooth and its consistency firm.
Its weight ranges between 15 and 20 grams.
The testicular parenchyma is surrounded by a very resistant fibrous tunica called tunica albuginea.
It is suspended by its posterior and superior region of the spermatic cord and is fixed by its lower pole to the scrotal covers by a fibrous tissue condensation called "gubernaculum testis".
It hangs in the scrotum with its upper pole tilted forward about 30 degrees and with the epididymis resting afterwards.
They are separated by a half-wall and housed inside the scrotal pouch,
where seven layers are covered that cover them.
These layers are: skin,
dartos,
subcutaneous cellular tunic,
external spermatic fascia,
cremaster,
internal spermatic fascia,
parietal tunica vaginalis and visceral tunica vaginalis.
The vascularization comes from the spermatic,
deferential and funicular arteries and its venous drainage is carried out by means of an anastomotic pampiniform network that converges forming the spermatic vein.
The epididymis is attached to the back of the testicle,
adopting a coma and consists of head,
body and tail.
The testicular appendages are intrascrotal embryological remains and four are distinguished: testicular appendix,
epididymal appendix,
paradidymus and aberrant epididymal duct.
Ultrasound technique and normal ultrasound findings.
As in other surface organs,
a high frequency probe (7.5-15 Mhz) with a linear transducer should be used.
In case of important scrotal edema,
lower frequency probes may be required.
The patient is examined in the supine position.
The scrotum is raised with a towel over the thighs or with the hand of the examiner and the penis is immobilized by the patient on his abdomen.
Both testicles should be explored transversally and sagittally,
comparing each testicle with the contralateral one in terms of shape,
size,
echogenicity and vascularization (with Doppler).
Both testes should show a homogeneous granular echoestructure similar to the thyroid.
Testicular septa are visualized as hypoechoic lines and the mediastinum as a hyperechoic line.
The tunica vaginalis appears as an echogenic line around the testicle.
The epididymis is shown as an isoechogenic structure with the testicle running along its posterior border,
distinguishing head,
body and tail.
Doppler examination of the arteries shows a pattern of low resistance in capsular and intratesticular arteries and low or high resistance in extratesticular circulation.