Thyroid and Scrotum

Calcitonin

Thyroid hormone that plays a role in regulating blood calcium levels

Parathyroid hormone

This hormone controls the serum calcium concentration using a feedback mechanism

Triiodothyronine (T3)

Primary thyroid hormone that plays a role in metabolism

Thyroid Stimulating Hormone (TSH)

Hormone secreted by the pituitary gland that stimulates the thyroid to produce T3 and T4

Thyroxine (T4)

Regulates the body's metabolism by controlling the rate at which cells use energy

Euthyroid

Normal functioning thyroid

Hyperthyroidism

Overly active thyroid

Isthmus

Band of tissue that connects the right and left lobes

Strap muscles

Group of three muscles that lie anterior to the thyroid gland - Sternohyoid, Sternothyroid, and Omohyoid

Longus coli muscle

Wedge-shaped muscles posterior to the thyroid lobes

Sternocleidomastoid muscles

Large anterior and lateral muscles to the thyroid

Pampiniform plexus

Cluster of veins that drain into the right and left testicular veins

Tunica vaginalis

Membrane consisting of the visceral and parietal layer that lines the inner portion of the scrotal wall, small amount of fluid may be present

Tunica albuginea

Fibrous membrane lining the testicle

Scrotum

Sac containing the testes and epididymis, maintains lower temperature

Mediastinum testis

A thick, incomplete septum of connective tissue that runs through the center of each testicle

Rete testes

Network of tubules within the mediastinum that carries sperm

Spermatic cord

Structure that is made up of the vas deferens, testicular artery, cremaster artery and pampiniform plexus that suspends the testis in the scrotum, extends from inguinal ring to scrotum

Epididymis

Coiled tube that connects the testicles to the vas deferens, where sperm mature

Vas Deferens

Muscular tube carrying mature sperm from the epididymis to the urethra, joins with seminal vesicles to become ejaculatory duct

Septa testis

Multiple septa formed by the tunica albuginea that course towards the mediastinum testis and separates the testes into lobules

Layers of testes: SOME darn englishman called it the testes

Skin

Layers of testes: some DARN englishman called it the testes

Dartos fascia and muscle

Layers of testes: some darn ENGLISHMAN called it the testes

external spermatic cord

Layers of testes: some darn englishman CALLED it the testes

Cremaster fascia

Layers of testes: some darn englishman called IT the testes

Internal spermatic fascia

Layers of testes: some darn englishman called it THE testes

Tunica vaginalis

Layers of testes: some darn englishman called it the TESTES

Tunica albuginea

Prenatal development of the testes

Start in lumbar region near the kidneys in development, descend by 12 weeks to level of bladder, approximately 1 month after birth it is in the normal position

Exocrine function of testicle

Sperm production

Endocrine function of testicle

Hormone production - testosterone

Length of testes

3-5cm

Width of testes

2-4cm

AP of testes

3cm

Where does sperm production start

in the seminiferous tubules and drains into straight tubules

The seminiferous tubules drain into the epididymis via the

efferent ductules

Seminal vesicles

Produce seminal fluid, lateral to vas deferens, superior to prostate, posterior/inferior aspect of bladder

Prostate gland

Extraperitoneal gland, plays a role in seminal fluid production, inferior to bladder, surrounds portion of urethra, anterior to rectum, superior to penis, walnut sized

Parts of Prostate: Central

ejaculatory ducts in this region of the prostate gland

Parts of Prostate: Peripheral

Apex to posterior

Parts of Prostate: Transition

Lateral to proximal urethra

Parts of Prostate: Anterior fibromuscular

Base to lateral

Seminal vesicles join with vas deferens to become

ejaculatory duct (which dumps into prostate gland)

Prostatic urethra runs through center of prostate gland from

bladder to perineum

Corpus cavernosum

Paired, upper surface of penis, arterial, related to crus

Corpus spongiosum

deeper, posterior/under surface of penis, close to urethra, venous plexus, related to bulb

USA of thyroid gland

homogeneous texture, mid-high level grays

AP of thyroid

2cm

Length of thyroid

4-6cm

Height of thyroid

13-18mm

Normal volume of thyroid

18 ± 4.5ml

Lab values we reference when looking at a pt’s hx with the thyroid

TSH, T4, T3

Hypercalcemia is associated with pathology of which gland

parathyroid