Genitourinary Anatomy Flashcards
1
Q
Where do the adrenal glands lie?
A
- Close to the upper pole of each kidney.
- Right lies behind liver and IVC.
- Left lies behind stomach and pancreas.
2
Q
How many arteries is each adrenal gland supplied by? Name these, and what they are branches of?
A
3 arteries:
- Superior adrenal artery (branch of the inferior phrenic artery).
- Middle adrenal artery (branch of the abdominal aorta).
- Inferior adrenal artery (branch of the renal artery).
3
Q
Describe the veinous drainage of the adrenal glands.
A
- Both drained by a single vein on each side (L + R adrenal veins).
- Right adrenal vein drains directly into IVC.
- Left adrenal vein drains into left renal vein, which then joins the IVC.
4
Q
Describe the composition of the adrenal gland.
A
Composed of a cortex (outer part) and medulla (inner part).
5
Q
What does the cortex of the adrenal gland produce?
A
Steroid hormones such as cortisol, aldosterone, and testosterone.
6
Q
What does the medulla of the adrenal gland produce?
A
Adrenaline.
7
Q
Describe the rough shape and size of the kidneys.
A
- Bean-shaped.
- Approx 11 x 7 x 3cm.
8
Q
What is the relationship between the kidneys and the periotneum?
A
- Located outside the peritoneum = extra-peritoneal.
- Behind the peritoneum = retro-peritoneal.
9
Q
Where are the kidneys located?
A
One on either side of the upper lumbar vertebrae.
10
Q
Describe what the kidney is embedded in/its coverings.
A
- Embedded in perinephric fat.
- This is covered by renal fascia.
- Further layer of paranephric fat over this.
11
Q
What can be found on the medial border of the kidney? What is found in this structure?
A
- Renal hilum.
- Where renal vessels, nerves, lymphatics, and the ureter enter/leave the kidney.
12
Q
Describe the blood supply of the kidneys.
A
Left and right renal arteries (branches of the abdominal aorta).
13
Q
Describe the venous drainage of the kidneys.
A
Left and right renal veins (both drain directly into IVC).
14
Q
What is the kidney composed of?
A
The cortex, medulla and the calyces.
15
Q
What is the medulla of the kidneys arranged into?
A
Renal pyramids.
16
Q
What are the functional units of the kidneys called, and what are they responsible for?
A
- Nephrons.
- Filtering blood, reabsorbing water and solutes, and secreting and excreting waste products as urine.
17
Q
Name 4 structures that can be found in the cortex of the kidneys.
A
- Glomeruli.
- Glomerular capsules.
- Proximal and distal tubules.
- Parts of the collecting ducts.
18
Q
Name 2 structures that can be found in the renal pyramids.
A
- Nephron loop (of Henle).
- Rest of the collecting ducts.
19
Q
From the collecting ducts, where does urine travel down the renal pyramids towards?
A
The renal papilla (apex of the pyramid).
20
Q
What structure does urine enter from the renal papilla? Which structures does it then pass through?
A
- A minor calyx.
- Minor calyces merge to form a major calyx.
- Major calyces merge to form the renal pelvis.
- The renal pelvis is continuous with the ureter.
21
Q
Where do the ureters carry urine to?
A
The urinary bladder.
22
Q
Describe the ureters’ structure.
A
Narrow tubes with muscular walls.
23
Q
How do the ureters transport urine?
A
By peristalsis.
24
Q
Where do the ureters run?
A
Anterior to psoas major on the posterior abdominal wall, cross the pelvic brim to enter the pelvis.
25
Describe the urinary bladder's structure.
A hollow, muscular organ.
26
Where is the urinary bladder found?
- Located in the pelvis.
- Posterior to the pubic symphysis, and anterior to the vagina and rectum.
27
What is the relationship between the urinary bladder and the peritoneum?
Below the peritoneum = infra-peritoneal.
28
What type of muscle is found in the bladder wall? What is it called? What does it do?
- Smooth muscle.
- Detrusor.
- Contracts to forcibly expel urine.
29
How much urine can a bladder accommodate in an adult?
~ 400-600ml.
30
Where do the ureters join the bladder? What is special about this?
- Posterior aspect of the bladder, near the base.
- Triangular area called the trigone, which has a smooth internal wall.
- Form a rudimentary valve by entering at an angle, prevents reflux of urine into ureters when the bladder is full.
31
Describe the rest of the inside wall of the urinary bladder, other than the trigone.
Corrugated with folds of mucosa called rugae.
32
What does rugae allow in the urinary bladder?
The bladder can stretch without tearing when it fills.
33
Describe the blood supply of the bladder.
Vesical arteries (branches of the internal iliac artery).
34
Describe the venous drainage of the bladder.
Vesical veins (drain into the internal iliac vein).
35
How many sphincters control the release of urine? What are these called?
2:
- Internal urethral sphincter.
- External urethral sphincter.
36
Describe the location, composition and control of the internal urethral sphincter.
- At the base of the bladder, where it opens into the urethra.
- Composed of smooth muscle.
- Under involuntary control.
37
Describe the location, composition and control of the external urethral sphincter.
- Just inferior to the prostate in males, and in the deep perineal pouch in females.
- Composed of skeletal muscle.
- Under voluntary control.
38
Describe the somatic innervation of the urinary bladder and urethral sphincters.
- Via branches of the pudendal nerve (S2-S4).
- Allows conscious control of the external urethral sphincter.
39
Describe the sympathetic innervation of the urinary bladder and urethral sphincters.
- Via branches of the hypogastric nerve (sympathetic chain, T12-L2).
- Causes relaxation of the detrusor, and contraction of the internal urethral sphincter: allowing storage of urine.
40
Describe the parasympathetic innervation of the urinary bladder and urethral sphincters.
- Via the pelvis splanchnic nerves (S2-S4).
- Causes contraction of the detrusor, and relaxation of the internal urethral sphincter: allowing initiation of micturition (urination).
41
Where does the urethra carry urine from and to?
- From the internal urethral orifice.
- To the external urethral orifice.
42
Where is the external urethral orifice located in males and females?
- Males: tip of the penis.
- Females: in the vestibule.
43
Roughly how long is the female urethra?
~ 3-4cm.
44
What are the 4 conventional subdivisions of the longer male urethra?
- Pre-prostatic.
- Prostatic.
- Membranous.
- Penile.
45
What else does the male urethra carry, other than urine?
Semen.
46
Where does the posterior abdominal wall extend from and to?
- From the attachments of the diaphragm superiorly.
- To the pelvis brim inferiorly.
47
What does the posterior abdominal wall consist of?
- Lumbar spine.
- Psoas and quadratus lumborum muscles.
48
Give 5 structures associated with the posterior abdominal wall.
- Aorta.
- IVC.
- Sympathetic trunks.
- Ureters (on the surface of the psoas muscles).
- Gonadal vessels (over the ureters).
49
What forms the lumbar plexus>
Lumbar spinal nerves L1-L4, with a contribution from teh T12 nerve.
50
What do the branches that the lumbar plexus give rise to innervate?
Skin and muscles of the abdominal wall and thigh.
51
Name 6 notable branches of the lumbar plexus that can be located in the posterior abdominal wall.
- Iliohypogastric nerves.
- Ilioinguinal nerves.
- Genitofemoral nerve.
- Lateral femoral cutaneous nerve.
- Femoral nerve.
- Obturator nerve
52
What do the iliohypogastric and ilioinguinal nerves supply?
The anterior abdominal wall muscles, and skin of the external genitalia.
53
What does the genitofemoral nerve supply?
The skin of the external genitalia.
54
What does the lateral femoral cutaneous nerve supply?
The skin over the lateral thigh.
55
What does the femoral nerve supply?
The muscles and skin of the anterior thigh.
56
What does the obturator nerve supply?
The muscles and skin of the medial thigh.
57
Where does the abdominal aorta begin, descend and terminate?
- Begins at level of T12.
- On the posterior abdominal wall, just to the left of the midline.
- Terminates by bifurcating at approx the level of L4.
58
What does the abdominal aorta bifurcate into at the level of ~L4?
Left and right common iliac arteries.
59
What are the 3 unpaired branches of the abdominal aorta?
- Coeliac trunk.
- SMA.
- IMA.
60
Name 4 paired branches of the abdominal aorta.
- Renal arteries.
- Adrenal arteries.
- Gonadal arteries.
- Lumbar arteries.
61
How is the IVC formed? Where?
- Union of the left and right common iliac veins.
- Approx level of L5.
62
Where does the IVC ascend, and pass through the diaphragm?
- On the posterior abdominal wall, just to the right of the midline.
- Passes at level of T8.
63
Which veins drain into the IVC?
- Those which correspond to the paired arteries branches of the abdominal aorta.
- Left gonadal and adrenal veins typically drains into left renal vein.
- Also receives hepatic veins.
64
Give 6 clinical relevancies of the adrenal glands, urinary tract and posterior abdominal wall.
- Urinary tract infection (UTIs).
- Renal cancer.
- Abdominal aortic aneurysm (AAA/triple A).
- Kidney stones (calculi).
- Phaeochromocytoma.
- Bladder stretch reflex and spinal cord injury.
65
What causes UTIs?
Almost always caused by bacteria (most common = E. Coli) entering the urinary bladder via the urethra.
66
Which gender are UTIs more common in? Why?
- Females.
- Shorter urethra.
67
What is infection of the urinary bladder called? Give 2 symptoms of this infection.
- Cystitis.
- Burning pain on passing urine (dysuria), and sensation of needing to pass urine much more frequently.
68
What is is called is cystitis spreads superiorly to the kidneys?
Pyelonephritis.
69
Give 4 symptoms of pyelonephritis.
- Fever.
- Flank pain.
- Nausea/vomiting.
- Cystitis symptoms.
70
What are the 3 main types of renal cancer?
- Renal cell carcinomas (RCC).
- Transitional cell carcinomas (TCC).
- Wilms' tumours.
71
Describe the histological origins of the 3 main types of renal cancer.
RCC - lining of the nephron.
TCC - epithelial lining inside the kidney.
Wilm's - renal stem cells.
72
What is the triad of symptoms which may present with renal cancer?
- Flank pain.
- Palpable abdominal mass.
- Haematuria (blood in the urine).
73
What is an aneurysm?
The bulging of a blood vessel, caused by a weak point in the blood vessel wall.
74
Give 4 risk factors for development of an AAA.
- Smoking.
- Alcohol.
- Hypertension.
- Atherosclerosis.
75
When are AAAs diagnosed?
If the diameter of the aorta is wider than 3cm.
76
What happens if an AAA ruptures?
Significant intra-abdominal bleeding occurs rapidly, mortality is high.
77
What are kidney stones most often composed of?
Calcium oxalate.
78
Give 4 risk factors for developing kidney stones.
- High urine-calcium levels.
- Dehydration.
- Obesity.
- Certain medications.
79
What can kidney stones obstruct if they are too large?
The ureter.
80
Describe the typical presentation of an obstructing kidney stone.
Excruciating, pulsatile pain felt from 'loin to groin'.
81
What will happen if the flow of urine from the kidney is obstructed? What are some possible risks of this happening?
- Kidney will fill with urine and swell (hydronephrosis).
- Can injure the kidney and may lead to infection.
82
What are the 3 regions of which the ureter narrows, meaning stones are most likely to get stuck at these points?
- Pelvi-ureteric junction (PUJ): between renal pelvis and ureter.
- Pelvic brim: where ureter runs over the pelvis brim, anterior to the iliac artery.
- Vesico-ureteric junction (VUJ): where ureter joins the bladder.
83
What is phaeochromocytoma?
A rare hormone-producing tumour of the adrenal medulla.
84
What symptoms may phaeochromocytoma produce and why?
- Hypertension, tachycardia, and excessive sweating.
- Because secretion of excess adrenaline causes symptoms and signs related to hyperactivity of the sympathetic NS.
85
What happens to bladder function if there is an injury to the spinal cord above the sacral level?
Patient does not realise they need to pass urine, and the bladder automatically empties as it fills = patient is incontinent of urine.
86
What happens to bladder function if there is an injury to the spinal cord at/below the sacral level?
The bladder fills with urine without emptying = overflow incontinence OR urinary retention.
87
Which centres control urination?
Those in the cerebral cortex, brainstem and sacral spinal cord (contains the sacral micturition centre).
88
Describe the bladder stretch reflex.
- Bladder fills, stretch of bladder wall detected, relayed to sacral spinal cord via visceral afferent fibres, these synapse directly onto motor neurons.
- Motor neurons (via parasympathetic fibres in pelvis splanchnic nerves) stimulate bladder contraction.
- This system = a reflex arc.
- Older children and adults can inhibit via descending pathways when it is not convenient to urinate.
89
What do ascending pathways do in relation to bladder function?
Convey sensation of bladder filling.
90
What do descending pathways do in relation to bladder function?
Exert voluntary, inhibitory control over the external urethral sphincter.
91
Give 3 functions of the bony pelvis.
- Supporting the spine, torso, and upper body.
- Locomotion.
- Housing and protecting the pelvis viscera.
92
What is the bony pelvis made up of?
3 bones:
- The sacrum.
- The left and right hip bones.
93
What are the hip bones made up of?
3 smaller bones that fuse together:
- The ilium.
- The ischium.
- The pubis.
94
Name the 5 articulations of the bony pelvis.
- Hip joint.
- Sacroiliac joint.
- Pubic symphysis.
- Lumbosacral joint.
- Sacrococcygeal joint.
95
Describe the hip joint.
- Between the head of the femur and the acetabulum (socket) of the pelvis.
- The 3 parts of the hip bone fuse at the acetabulum.
96
Describe the sacroiliac joint.
- Between the sacrum and the ileum of the hip bone.
- Very stable and strong, supported by many ligaments.
97
Describe the pubic symphysis.
- Between the two pubic bones at the front of the pelvis.
- Very little movement permitted.
98
Describe the lumbosacral joint.
- Between the 5th lumbar vertebra and the sacrum.
- An intervertebral disc lies between the two.
99
Describe the sacrococcygeal joint.
- Between the sacrum and the coccyx.
100
Give 6 surface landmarks of the bony pelvis.
- Iliac crest.
- Anterior superior iliac spine (ASIS).
- Iliac tubercle.
- Pubic tubercle.
- Inguinal ligament.
- Mid-inguinal point.
101
Give the 3 differences between male and female bony pelves.
- Wider, circular pelvic inlet in females (for childbirth); narrower, heart-shaped inlet in males.
- Obtuse angle formed by inferior pubic rami in females; acute angle in males.
- Wider and shorter sacrum in females; narrower, longer sacrum in males.
102
What does the pelvis contain?
- Bladder and rectum.
- Uterus, ovaries and vagina (females).
- Prostate and seminal vesicles (males).
- Arteries, veins and nerves.
103
What is the pelvic floor? Describe its shape.
- The collective name for several muscles that support the pelvic organs from below.
- Like a bowl or funnel.
104
What do the muscles of the pelvic floor separate?
The pelvis from the perineum.
105
What are the 3 primary functions of the pelvic floor muscles?
- Prevent herniation of the pelvic organs inferiorly, out of the pelvis.
- Control continence of urine and faeces by providing a sphincter action on the urethra and rectum.
- Aid in increasing intra-abdominal pressure.
106
Give the names of the muscles of the pelvic floor.
- The levator ani (composed of 3 smaller muscles: puborectalis, pubococcygeus, and iliococcygeus).
- The coccygeus.
107
Describe the innervation of the levator ani.
By a branch of the S4 nerve, and by some branches of the pudendal nerve (from S2-S4).
108
Describe the arterial supply of the pelvis.
- Left and right internal iliac arteries.
- Give rise to several branches that supply pelvis viscera as well as branches to supply the perineum and gluteal region.
109
Give 6 key branches of the internal iliac arteries, and what they supply.
- Vesical arteries (bladder in both, and prostate and seminal vesicles in males).
- Uterine and vaginal arteries (females).
- Middle rectal artery (rectum).
- Internal pudendal artery (perineum).
- Superior and inferior gluteal arteries (gluteal region).
- Obturator artery (lower limb).
110
Describe the venous drainage of the pelvis.
- Contains several venous plexuses which drain the pelvic organs.
- Plexuses unite and mostly drain into the internal iliac veins.
111
Give 4 key nerves arising from the sacral plexus.
- Sciatic nerve.
- Pudendal nerve.
- Superior and inferior gluteal nerves.
- Pelvic splanchnic nerves.
112
Describe the sciatic nerve.
- Formed by L4-S3 nerves.
- Exits pelvis and supplies lower limb.
113
Describe the pudendal nerve.
- Somatic nerve.
- Derived from spinal nerves S2-S4.
- Exits pelvis and supplies perineum.
114
Describe the superior and inferior gluteal nerves.
- Exit pelvis and innervate the gluteal region.
115
Describe the pelvic splanchnic nerves.
- Carry parasympathetic fibres from S2-S4 spinal cord segments, to pelvic viscera.
116
Where are sympathetic fibres that innervate the pelvic viscera derived from?
The lumbar splanchnic nerves.
117
How long is the rectum approximately?
~12cm in an adult.
118
What are the 2 notable flexures of the rectum called?
- The sacral flexure (anteriorly).
- The anorectal flexure (posteriorly).
119
Give the names of the 3 arteries that supply the rectum, and what they are branches of.
- Superior rectal artery (branch of IMA).
- Middle rectal artery (branch of internal iliac artery).
- Inferior rectal artery (branch of internal pudendal artery, itself a branch of the internal iliac artery).
120
Describe the venous drainage of the rectum.
- Superior, middle and inferior rectal veins.
- Branches of these veins anastomose with each other = venous plexus (around the rectum and anus).
- Therefore, a site of portosystemic anastomoses.
121
Where is the perineum found?
- Immediately superficial and inferior to the pelvic floor.
- Superficial region between the pubic symphysis and coccyx.
- Medial surfaces of the thighs.
122
Describe the shape of the perineum, and any divisions.
- Diamond-shaped.
- Can be split into two triangles by drawing an imaginary line between ischial tuberosities.
- The urogenital triangle (anteriorly).
- The anal triangle (posteriorly).
123
What does the urogenital triangle contain?
- Urethral and vaginal openings.
- The erectile tissues that unite to form the clitoris or penis.
- Muscles overlying them.
124
How many layers are there if the urogenital triangle? Name them.
4:
- Skin.
- Perineal fascia.
- Superficial perineal pouch.
- Perineal membrane.
125
Describe the skin layer of the urogenital triangle.
The urethra and vagina open out through the skin.
126
Describe the perineal fascia layer of the urogenital triangle.
A continuation of the fascia overlying the abdominal wall muscles.
127
Describe the superficial perineal pouch of the urogenital triangle.
A potential space that contains the erectile tissues of the clitoris or penis, and three muscles (ischiocavernous, bulbospongiosus, and the superficial transverse perineal muscles).
128
Describe the perineal membrane of the urogenital triangle.
- Strong, fibrous membrane that provides support for the attachment of ischiocavernous and bulbospongiosus muscles.
- Urethra and vagina pass through it.
129
What does the anal triangle contain?
The anal canal and anus.
130
How long is the anal canal approximately?
~4cm in an adult.
131
Where is the anal canal?
Extends from the distal rectum to the anus.
132
What does the pectinate (dentate) line divide?
The anal canal into superior and inferior parts.
133
How many anal sphincters control defecation?
Two:
- Internal and external.
134
Describe the internal anal sphincter.
- Composed of smooth muscle.
- Involuntarily controlled.
135
Describe the external anal sphincter.
- Composed of skeletal muscle.
- Voluntarily controlled.
136
Describe the superior part of the anal canal.
- Part of the hindgut, derived from endoderm.
- Columnar epithelium lines the lumen.
- Encircled by the internal anal sphincter.
137
Describe the blood supply of the superior part of the anal canal.
IMA via the superior rectal artery.
138
Describe the venous drainage of the superior part of the anal canal.
Via the portal venous system towards the liver.
139
Describe the innervation of the internal anal sphincter.
- Sympathetic fibres (from the sympathetic trunk).
- Parasympathetic fibres (via the pelvic splanchnic nerves).
140
Describe the inferior part of the anal canal.
- Derived from ectoderm.
- Stratified squamous epithelium lines the lumen.
141
Describe the blood supply of the inferior part of the anal canal.
Middle and inferior rectal arteries, which originate from the internal iliac arteries.
142
Describe the venous drainage of the inferior part of the anal canal.
Systemic venous system (not the portal system).De
143
Describe the innervation of the external anal sphincter.
Pudendal nerve (somatic).
144
What is the perineal body? What does it do?
- A dense mass of fibrous tissue and muscle.
- Acts as an attachment for almost all the perineal and pelvic floor muscles.
145
Where can the perineal body be found?
Sitting between the two triangles of the perineum.
146
Give 3 clinical relevancies of the pelvis, rectum, pelvic floor and perineum.
- Pelvic floor weakness.
- Episiotomy.
- Haemorrhoids.
147
Give 4 factors that can stretch, damage, or weaken the pelvic floor muscles.
- Childbirth.
- Aging.
- Straining.
- Obesity.
148
What is pelvic organ prolapse?
Uterus prolapses into vagina, or rectum prolapses out of the anus; as they are no longer supported.
149
What is an episiotomy? When and why would you have one?
- A pre-emptive incision lateral to the perineal body, to avoid injury to the peritoneal body or an uncontrolled tear through the anal sphincter during childbirth.
150
What are haemorrhoids?
Cushions formed from the abundance of veins on the walls of the anal canal. These can become swollen and inflamed.
151
When are haemorrhoids painless?
If they become inflamed above the pectinate line.
152
When are haemorrhoids painful?
If they become inflamed below the pectinate line.
153
If haemorrhoid are pathological, what symptom may occur?
Bleeding when passing stool.
154
What leads to haemorrhoids becoming swollen and problematic? Give 4 examples.
Increased intra-abdominal pressure:
- Excessive straining.
- Constipation.
- Squatting.
- Pregnancy.
155
How long is the inguinal canal? Where does it extend from/to?
- ~5cm in the adult.
- From the deep inguinal ring laterally, to the superficial inguinal ring medially.
156
What is the deep inguinal ring?
An aperture in the transversalis fascia.
157
What is the superficial inguinal ring?
An aperture in the external oblique aponeurosis.
158
Describe the anterior border of the inguinal canal.
- EO aponeurosis.
- Laterally only: IO aponeurosis.
159
Describe the posterior border of the inguinal canal.
- Transversalis fascia.
- Medially only: medial fibres of the aponeuroses of the IO and transversus abdominis.
160
Describe the roof of the inguinal canal.
- Transversalis fascia.
- Arching fibres of the IO aponeurosis and transversus abdominis.
161
Describe the floor of the inguinal canal.
- Inguinal ligament (lower border of EO aponeurosis).
162
What 3 structures does the female inguinal canal contain?
- Round ligament of the uterus.
- Ilioinguinal nere.
- Genital branch of the genitofemoral nerve.
163
In males, where are most of the contents of the inguinal canal contained? What is the exception?
- The spermatic cord.
- Except the ilioinguinal nerve.
164
What are the contents of the spermatic cord divided into?
- 2 nerves.
- 3 arteries.
- 3 fascial layers.
- 4 other structures.
165
Which 2 nerves are found in the spermatic cord?
- Genital branch of the genitofemoral nerve.
- Sympathetic nerve fibres.
166
Which 3 arteries are found in the spermatic cord?
- Testicular artery.
- Cremasteric artery.
- Artery to the vas deferens.
167
What are the 3 fascial layers in the spermatic cord? Where do they derive from?
- External spermatic fascia (from EO aponeurosis).
- Cremaster muscle and fascia (from IO aponeurosis).
- Internal spermatic fascia (from transversalis fascia).
168
What are the 4 'other' structures found in the spermatic cord?
- Pampiniform venous plexus.
- Lymphatics.
- Vas deferens (plural: vasa deferentia).
- Processus vaginalis (derived from peritoneum).
169
Where are the testes located?
Within the scrotum.
170
Describe scrotal skin.
Thin, wrinkled and more darkly pigmented than skin elsewhere.
171
What is beneath the scrotal skin?
- A thin layer of superficial fascia.
- Then a thin, involuntary muscle called the dartos.
172
What extends between the testes to form a septum dividing the scrotum into halves?
The superficial fascia.
173
What 3 structures does each half of the scrotum contain?
- A testis.
- An epididymis.
- A distal part of the spermatic cord.
174
What do the testes produce? What do they secrete?
- Produce sperm.
- Secrete testosterone.
175
What shape are the testes?
Ovoid (egg-shaped).
176
What covers the testes?
- The 3 layers of spermatic fascia that cover the spermatic cord.
- Partially surrounded by a sac called the tunica vaginalis (derived from the peritoneum).
177
Describe the structure of the epididymis.
- Coiled tube lying along the posterior border of each testis.
- Expanded head superiorly, a body, and a pointed tail lying at the lower pole of the testis.
178
What does the epididymis store?
Spermatozoa.
179
What does the vas deferens do? Where does it travel?
- Carries sperm from the epididymis up the spermatic cord and through the inguinal canal into the pelvis
- Travels with the testicular vessels in the spermatic cord.
180
What are the testicular arteries direct branches of?
The abdominal aorta.
181
Venous blood from where enters the pampiniform venous plexus?
From the testis and epididymis.
182
What vein does the pampiniform venous plexus form?
The testicular vein.
183
What does the right testicular vein enter?
The IVC.
184
What does the left testicular vein join?
The left renal vein.
185
How many cylinders of erectile tissue does the penis compose of? What are these called? Which are dorsal/ventral?
3:
- 2 corpora cavernosa dorsally.
- 1 corpus spongiosum ventrally.
186
What is the end of the penis called? What is it an extension of?
- The glans.
- Extension of the corpus spongiosum.
187
What is the circular base of the glans called?
The corona.
188
What is the skin of the shaft that extends over the glans called?
The foreskin.
189
What is the procedure called in which the foreskin is removed?
Circumcision.
190
What do the corpora cavernosa originate along, and where do they converge?
- The left and right ischial rami.
- Converge in the midline.
191
What are the parts of the corpora cavernosa attached to the left and right ischial rami called?
Crura (singular: crus).
192
Where does the corpus spongiosum sit?
In the midline.
193
What is the part of the corpus spongiosum attached to the perineal membrane called?
The 'bulb' of the penis.
194
What does the penile urethra lie within?
The corpus spongiosum.
195
What does the penile urethra carry?
Urine and semen.
196
Where does the penile urethra open?
Via the external urethral meatus.
197
What muscles cover the corpora cavernosa?
The ischiocavernosus muscles.
198
What muscle covers the corpus spongiosum?
The bulbospongiosus.
199
What do the ischiocavernosus muscles do?
Force blood into the body of the penis from the crura.
200
What does the bulbospongiosus muscle do?
- Forces blood into the glans penis.
- Assists in maintaining erection by compressing the veins that drain erectile tissues.
- Contracts to squeeze any remaining urine or semen from the urethra.
201
Describe the arterial supply to the penis.
- Via the internal pudendal arteries (branch from the internal iliac artery).
- Branches of the internal pudendal include the deep artery of the penis, and the artery of the bulb of the penis.
202
Describe the nervous supply to the penis.
- From S2-S4 nerves.
- General sensation and sympathetic innervation carried by dorsal nerve of the penis (branch of the pudendal nerve).
- Parasympathetic nerve fibres arise from the peri-prostatic nerve plexus.
- Ischiocavernosus and bulbospongiosus muscles innervated by pudendal nerve (S2-S4).
203
What are parasympathetic nerve fibres of the penis responsible for?
Causing erection by dilating the arteries of the corpora.
204
What is the role of the corpora cavernosa during a penile erection?
- Responsible for the increase in size and rigidity of the penis during an erection.
- During sexual arousal, arterial blood flow -> corpora increases, so corpora becomes engorged with blood.
205
What is the role of the corpus spongiosum during a penile erection?
- Becomes engorged, but not to the same extent as the corpora cavernosa.
- Main role during erection is to prevent the urethra from being compressed, which would prevent ejaculation.
206
What is the dilated portion of the vas deferens called?
The ampulla.
207
How does the vas deferens terminate?
By joining the duct of the seminal vesicle to form the ejaculatory duct.
208
Describe the seminal vesicles.
- Lobulated sacs.
- About 4cm long.
- Lie laterally to the ampulla of the vas deferens.
209
What do the seminal vesicles secrete?
A thick alkaline fluid, which forms the bulk of seminal fluid (aka semen).
210
What does the ejaculatory duct pierce to enter the prostatic urethra?
The back of the prostate gland.
211
Describe the prostate.
- Roughly spherical fibromuscular gland, about the size of a walnut.
- Lies against the neck of the bladder, pierced by the urethra and ejaculatory ducts.
- Secretions are added to the seminal fluid during ejaculation.
212
Which artery's branches supply the vas deferens, seminal vesicle and prostate?
Branches of the internal iliac artery.
213
Give 10 clinical relevancies of the male external genitalia and pelvic organs.
- Hydrocoele.
- Varicocele.
- Epididymo-orchitis.
- Testicular torsion.
- Cryptorchidism.
- Testicular cancer.
- Vasectomy.
- Erectile dysfunction.
- Benign prostatic hyperplasia.
- Prostatic malignancy.
214
What is a hydrocoele?
A painless scrotal swelling caused by an accumulation of peritoneal fluid between the layers of the tunica vaginalis around the testis.
215
What technique can be used to diagnose hydrocoele?
Transillumination - when a light is shone through a hydrocoele, it can be seen from the other side.
216
What is a varicocele?
An abnormal dilation of the pampinform venous plexus, which causes a scrotal swelling.
217
How may a varicocele be describe on palpation, and why?
Feeling like a 'bag of worms', due to dilated veins.
218
Which side are varicoceles more common and why?
- Left side.
- As the left testicular vein drains into the left renal vein before it drains into the IVC, therefore left-sided varicocele could be caused by an obstruction to the left renal vein.
219
What is epididymo-orchitis?
A painful inflammation of the epididymis and testis.
220
What can cause epididymo-orchitis?
- Sexually-transmitted infections such as chlamydia or gonorrhoea.
- Urinary tract infections.
221
What is testicular torsion and what can it lead to?
Twisting of the testis on the spermatic cord, which can lead to ischaemia of the testis - a surgical emergency.
222
How do patients with testicular torsion usually present?
With a sudden, very painful and tender testis; which may be positioned higher or at an unusual angle.
223
What can testicular torsion lead to if left untreated?
Necrosis and loss of the affected testis.
224
What is cryptorchidism?
Undescended testes during foetal development.
225
What are 2 core problems with cryptorchidism?
- Spermatogenesis is optimal just below core body temperature, so testes will only function correctly in the scrotum.
- Increased risk of testicular cancer is the undescended testis is left inside the abdomen.
226
What is normally done to undescended testes?
Often brought into the scrotum surgically.
227
What is likely to happen is testicular cancer metastasises?
- It will likely follow the lymphatic drainage which follows the testicular arteries back to lymph nodes around the aorta.
- Therefore, testicular cancer metastasises first to para-aortic or retroperitoneal lymph nodes.
228
What is a vasectomy?
A means of male sterilisation (permanent male contraception).
229
How is a vasectomy performed?
- Scrotum is incised, vasa deferentia are located on each side.
- Vasa deferentia are then ligated, cauterised or clamped to prevent the passage of sperm from the testes.
230
How can erectile dysfunction be treated?
- Finding the cause and treating that (nervous system, psychological issue etc.).
- Using medications such as sildenafil (Viagra) which increase blood flow into the corpora of the penis.
231
What is benign prostatic hyperplasia (BPH)?
BPH is common with progressing age, it is when the prostate enlarges in a benign manner.
232
What can BPH lead to? What would this then require?
- May lead to compression of the urethra and urinary retention.
- Would require catheterisation to drain the urine.
233
Where does prostate cancer commonly metastasise to, and why?
- The vertebrae.
- As venous blood from the prostrate -> plexus of veins which lie anterior to the sacrum and communicate with veins which run up the azygos vein in the chest. These veins communicate with veins in the vertebral bodies.
234
What is a digital rectal exam/per rectum?
A DRE/PR is when a gloved and lubricated finger is inserted into the rectum via the anus, and is flexed anteriorly to palpate the prostate, which lies immediately anterior to the anal canal and rectum.
235
What can clinicians feel in a DRE/PR? What may be concerning for malignancy?
- Size, contour and firmness of the prostate.
- Concerning = hard, craggy prostate.
236
What is the vulva?
A collective term for all parts of the female external genitalia.
237
What are the 9 named parts of the vulva?
- Mons pubis.
- Labia majora.
- Labia minora.
- Clitoris.
- Vestibule.
- Vaginal opening.
- Hymen.
- Urinary meatus.
- Vestibular glands.
238
Describe the mons pubis.
Mound of fatty tissue located in front of the pubic symphysis causing an elevation of the hair-bearing skin.
239
Describe the labia majora.
Prominent hair-bearing folds of skin that meet at the mons pubis anteriorly.
240
Describe the labia minora.
- Smaller, hairless folds of skin located medial to the labia majora.
- Fuse together anteriorly to form the hood of the clitoris.
- Form the boundaries of the vestibule.
241
Describe the clitoris.
- Pea-sized, highly sensitive tissue comprised of the erectile corpora cavernosa and corpus spongiosum.
- Becomes engorged during sexual arousal.
242
Describe the vestibule.
- Area between the labia minora.
- Contains the vaginal opening, urinary meatus and vestibular glands.
243
Describe the vaginal opening.
- Entrance to the vagina.
- Also known as the vaginal introitus.
244
Describe the hymen.
- Thin membrane that partially covers the vaginal opening.
- Often ruptures during the first episode of sexual intercourse and historically its presence was taken as proof of virginity. However, it can rupture
spontaneously, during exercise, by using tampons or menstrual cups, or it may simply be absent altogether.
245
Describe the urinary meatus.
- Opening of the urethra.
- Located posterior to the clitoris, but anterior to the vaginal opening.
246
Describe the vestibular glands.
- Greater vestibular glands - also known as Bartholin’s glands - they are located just posterior to the vaginal opening and secrete a lubricant into the
vagina during sexual arousal.
- Lesser vestibular glands - also known as Skene’s glands - they lie near the urethral opening. The function of the fluid they secrete is debated but it may
lubricate the vaginal opening or urethra, or have an antimicrobial effect.
247
What is the clitoris formed of?
- 2 corpus cavernosa.
- The glans clitoris.
248
Describe the corpus spongiosum in females.
Lies in the midline, but splits into 2 parts that flank the vaginal opening - these are named the bulbs of the vestibule/clitoris.
249
What does the ischiocavernosus muscles do in females?
Force blood from the crura to the body of the clitoris.
250
What does the bulbospongiosus muscle do in females?
- Forces blood into the glans clitoris.
- Helps to maintain clitoral erection and constricts around the vaginal orifice, which can help expression of fluid from the greater vestibular glands.
251
Describe the blood supply of the clitoris.
Via the internal pudendal arteries from the internal iliac arteries - branches include the deep arteries of the clitoris and the arteries of the bulb of the vestibule.
252
Describe the innervation of the clitoris.
- Erectile tissues of the clitoris: by parasympathetic nerves.
- Ischiocavernosus and bulbospongiosus are innervated by pudendal nerve (S2-S4).
253
How many nerves innervate the vulva? What are they called?
4 nerves:
- Ilioinguinal nerve.
- Genital branch of the genitofemoral nerve.
- Pudendal nerve.
- Posterior cutaneous nerve of the thigh.
254
Describe the shape and size of the ovaries.
- Almond-shaped.
- 4cm long and 2cm wide.
255
Describe the attachments and position of the ovaries.
- Attached to the posterior aspect of the broad ligament by the mesovarium.
- Position not fixed, but frequently lies in the ovarian fossa.
256
What forms the ovarian fossa?
The angle between the internal and external iliac arteroes.
257
Name 2 structures that are closely related to the ovarian fossa.
The ureter and the obturator nerve.
258
Describe the shape and size of the uterus.
Pear-shaped, hollow muscular organ, about 8cm long.
259
What are the 3 parts of the uterus?
- Fundus (above the uterine tubes).
- Body.
- Cervix.
260
How is the body of the uterus typically angled and where does it rest?
- Anteriorly.
- Rests on the superior surface of the bladder.
261
What forms the broad ligament?
The fold of peritoneum that covers the uterus and adheres itself at its sides forms the broad ligament.
262
What is the name of the space behind the uterus but anterior to the rectum? What is it lined with?
- Rectouterine pouch (pouch of Douglas).
- Peritoneum.
263
What do the uterine/fallopian tubes carry?
Ova, from the ovary towards the uterine cavity.
264
How long are the fallopian tubes? Where do they lie?
- About 10cm long.
- Run in the upper border of the broad ligament.
265
Describe the shape of the fallopian tubes.
- Near the uterus, narrow isthmus.
- Laterally, a dilated ampulla, leading into a funnel-shaped infundibulum.
- Free edge of the infundibulum is broken up into fimbrae, which are draped over the ovary.
266
What is the narrow lumen of the cervix called? What does it communicate with and how?
The cervical canal, which communicates with the uterine cavity via the internal os and with the vagina via the external os.
267
What are the vaginal fornices?
The recesses created by the lower part of the cervix lying inside the vagina.
268
How is the position of the cervix stabilised?
By the tone of the levator ani muscle and ligaments which run from the lateral wall of the cervix to the lateral pelvic wall at the base of the broad ligament.
269
What is the vagina?
The excretory duct of the uterus.
270
Describe the size and location of the vagina.
- Approx 10cm long.
- Bordered superiorly by the cervix.
- Terminates below at the introitus by opening into the vestibule between the labia minora.
- Upper 2/3 lie in the pelvic cavity.
- Lower 1/3 in the perineum.
271
How are the bladder and the urethra related to the vagina?
- Vagina closely related to the bladder anteriorly.
- Urethra often embedded in the anterior wall of the lower third of the vagina.
272
Describe the blood supply of the ovaries.
Ovarian artery, a direct branch of the abdominal aorta.
273
Give 8 clinical relevancies of the female external genitalia and pelvic organs.
- Endometriosis.
- Fibroids.
- Ovarian cancer.
- Cervical cancer.
- Hysterectomy.
- Ectopic pregnancy.
- Sterilisation.
- Female genital mutilation.
274
What is endometriosis?
A condition in which endometrial tissue is found outside the uterus. Most commonly deposits affect the ovaries, uterine tubes, uterine ligaments and rectouterine pouch; but rarely, it can even leave the pelvis and end up at distant sites such as the thorax.
275
What are 4 symptoms of endometriosis?
- Painful periods.
- Heavy bleeding during periods.
- Chronic pelvic pain.
- Pain during intercourse.
276
What can endometriosis cause difficulty in?
Conception.
277
How is endometriosis formally diagnosed?
By a diagnostic laparoscopy.
278
What are fibroids?
Benign growths of the uterus that vary in size and can grow very large.
279
How may fibroids present?
- Can be asymptomatic.
- Can cause varied symptoms such as painful and heavy periods.
280
What difficulty could fibroids cause?
Can make it difficult to conceive if they grow into the lumen of the uterus.
281
Give 6 symptoms of gynaecological cancers.
- Pelvic pain.
- Abnormal vaginal discharge.
- Abnormal vaginal bleeding.
- Urinary disturbance.
- Abdominal swelling.
- Non-specific symptoms of malignancy such as fatigue or weight loss.
282
When is ovarian cancer often diagnosed? Why?
- Late diagnosis.
- Symptoms tend to be non-specific e.g. abdominal bloating, pelvic pain, loss of appetite and weight loss.
283
What are most cases of cervical cancer caused by?
Infection with specific types of human papillomavirus (HPV).
284
How is cervical cancer attempted to be prevented?
- Children in UK offered HPV vaccine.
- Females age 25-64 in UK are regularly invited for a cervical screening.
285
What is a hysterectomy?
Surgical removal of the uterus. There are several types of hysterectomies.
286
What is the most common type of hysterectomy? What does this procedure entail?
A total hysterectomy - removal of the entire uterus, including the cervix and uterine tubes.
287
Give 4 reasons that a hysterectomy may be recommended.
- Uterine fibroids.
- Endometriosis.
- Uterine prolapse.
- Endometrial hyperplasia.
288
What is an ectopic pregnancy?
When a blastocyst implants outside the body of the uterus.
289
What is the most common place for an ectopic pregnancy to implant?
The uterine tube.
290
What can happen due to an ectopic pregnancy?
- Uterine tube cannot stretch to accommodate the growing embryo, so may rupture.
- This can cause pain and internal bleeding (it can be life-threatening).
291
What is often required with an ectopic pregnancy?
Surgery to remove the pregnancy from the uterine tube.
292
What is female sterilisation?
Interrupting the uterine tubes so that the sperm and egg cannot meet.
293
How is female sterilisation carried out?
Laparoscopically, either by using devices to clamp the tubes shut or by removing a small segment of tube.
294
Name 6 serious problems that FGM can cause.
- Chronic pain.
- Infections.
- Painful intercourse.
- Complications in labour.
- Emotional trauma.
- Mental health problems.
