Urology: Anatomy & Physiology

Urinary Tract

Urinary Tract
  • Upper Urinary Tract:
    • Kidney
    • Ureter: Draining Urine from the Kidney/Renal Pelvis to the Bladder
  • Lower Urinary Tract:
    • Bladder
    • Urethra: Empties Urine
Gerota’s Fascia
  • Fascia Surrounding the Kidney & Perirenal Fat
  • Anterior & Posterior Leaves
    • Fuse Medially, Laterally & Superiorly
    • Remains Open Inferiorly (Ureter & Gonadal Vessels Exit)
Renal Hilum/Vasculature
  • Structures (Anterior to Posterior): Mn
    • Renal Vein > Renal Artery > Renal Pelvis
  • Right Renal Artery: Travels Posterior to IVC
  • Left Renal Vein: Travels Anterior to Aorta
    • Can Be Ligated Distally Due to High Collaterals
      • Right Too Short & Lacks Collaterals
    • Branches of Left Renal Vein: (To IVC on the Right)
      • Gonadal Vein
      • Adrenal Vein
      • Second Lumbar Vein
Ureter Course
  • Tubular Structures Draining Urine from the Kidney/Renal Pelvis to the Bladder
    • Diameter: 2-6 mm
    • Length: 20-30 cm
  • Abdominal Ureter: Descends Along the Anterior Edge of the Psoas Muscle to the Pelvic Brim
    • Close Relationship to the Ipsilateral Colon
    • At the Pelvic Brim They Cross Over the Common Iliac Vessels (Generally Where the Vessels Bifurcates into Internal/External)
  • Pelvic Ureter: Descend Along the Side Walls of the Pelvis (From the Pelvic Brim to the Bladder)
    • Enters the Posterior Wall of the Bladder & Drains into the Trigone

Kidney & Renal Hilum 1

Branches of the Left Renal Vein: Phrenic, Adrenal, Second Lumbar, Gonadal & Ureteral 2

Male Genitalia

Male Reproductive System

  • Testis – Produce Sperm in the Seminiferous Tubules & Secrete Hormones
  • Epididymis – Mature Sperm & Transfer from the Testis to Vas Deferens
  • Vas Deferens (Ductus Deferens) – Transfers Sperm to the Ejaculatory Duct
  • Accessory Glands:
    • Seminal Vesicles – Located Behind the Bladder & Secretes Fluid to Compose Semen
    • Prostate Gland – Located Below the Bladder Around the Urethra & Produces Fluid to Compose Semen
    • Bulbourethral Gland – Located at the Base of the Penis, Posterolateral to the Membranous Portion of the Urethra & Produces Pre-Ejaculate Fluid
  • Ejaculatory Duct – Passes Semen Through the Prostate into the Urethra During Ejaculation
    • Formed by the Vas Deferens & Seminal Vesicles
  • External Organs:
    • Penis
    • Scrotum

Gonadal Vasculature

  • Gonadal Arteries: From Aorta
  • Gonadal Veins
    • Left: To Left Renal Vein
    • Right: To IVC

Lymphatics of the Testicles

  • Right: Paracaval & Interaortocaval Lymph Nodes
  • Left: Para-Aortic Lymph Nodes

Spermatic Cord Contents

  • Testicular Artery
  • Pampiniform Plexus
  • Vas Deferens
  • Cremasteric Muscle
  • Ilioinguinal Nerve
  • Genital Branch of Genitofemoral Nerve

Male Urethra Segments

  • Posterior Urethra:
    • Prostatic (3 cm) – Through the Prostate Gland
    • Membranous (1 cm) – Through the Urogenital Diaphragm/External Urethral Sphincter
  • Anterior Urethra:
    • Bulbar – The Root of the Penis
    • Penile/Spongy (16 cm) – Through the Corpus Spongiosum

Penis Structure

  • Three Columns:
    • Corpora Cavernosa (x2) on Dorsal Side – Fills with Blood to Create an Erection
    • Corpus Spongiosum (x1) on Ventral Side – Erectile Tissue Surrounding the Urethra
  • Parts:
    • Root of the Penis – Attached to the Body, Composed of the Crura & Urethral Bulb
    • Body of the Penis – External Portion
    • Glans Penis (Head) – Distal Bulbous End of the Penis
    • Foreskin (Prepuce) – Fold of Tissue Covering the Glans Penis (Can Be Involved in Various Infections)

Male Reproductive System 3

Scrotum & Spermatic Cord 4

Penis Cross-Section 4

Mnemonics

Renal Hilum Structures (Anterior to Posterior)

  • VAP: Vein-Artery-Pelvis
  • VA-AP: Vein Anterior to Aorta, Artery Posterior to IVC

References

  1. Blaus B. Wikimedia Commons. (License: CC BY-3.0)
  2. Tröbs RB. Anatomical basis for Wilms tumor surgery. J Indian Assoc Pediatr Surg. 2009 Apr;14(2):50-4. (License: CC BY-2.0)
  3. ScientificAnimations.com. Wikimedia Commons. (License: CC BY-SA-4.0)
  4. Gray H. Anatomy of the Human Body (1918). Public Domain.