URETER - ANATOMY, PHYSIOLOGY, EMBRYOLOGY

1. EMBRYOLOGY , ANATOMY
AND PHYSIOLOGY OF
URETER
Dept of Urology
Govt Royapettah Hospital and Kilpauk Medical College
Chennai
1
Dept of Urology, GRH and KMC, Chennai.

2. Moderators:
Professors:
• Prof. Dr. G. Sivasankar, M.S., M.Ch.,
• Prof. Dr. A. Senthilvel, M.S., M.Ch.,
Asst Professors:
• Dr. J. Sivabalan, M.S., M.Ch.,
• Dr. R. Bhargavi, M.S., M.Ch.,
• Dr. S. Raju, M.S., M.Ch.,
• Dr. K. Muthurathinam, M.S., M.Ch.,
• Dr. D. Tamilselvan, M.S., M.Ch.,
• Dr. K. Senthilkumar, M.S., M.Ch.
Dept of Urology, GRH and KMC, Chennai. 2

3. ❑Introduction
❑Embryology
❑Microscopic
❑Parts of ureter
❑Blood supply & Nerve supply
❑Radiological Anatomy
❑Endoscopic anatomy
❑Physiology
3
Dept of Urology, GRH and KMC, Chennai.

4. INTRODUCTION
• B/L muscular retroperitoneal tubes as extension of the renal
pelvis
• Length - 22-30 cm (Adults) ;
6.5-7.0 cm (Neonates)
• Diameter = 1.5- 6.0 mm.
• Lateral to tips of transverse processes of lumbar vertebra.
• LEFT ureter is slightly longer than the right. 4
Dept of Urology, GRH and KMC, Chennai.

5. URETERAL SEGMENTATION & NOMENCLATURE :
• Upper
Renal pelvis to upper border of sacrum
• Middle
Upper to lower border of sacrum
• Lower
Lower border of sacrum till bladder
5
Dept of Urology, GRH and KMC, Chennai.

6. International Anatomic
Terminology :
Abdominal
Pelvic
Intramural segments
6
Dept of Urology, GRH and KMC, Chennai.

7. EMBRYOLOGY
• Mesodermal derivative.
• From Ureteric bud (from
mesonephric duct)
• Ureteric bud ascends up, divides and
ingrows into metanephric blastema
to form renal calyces
❑ Abnormalities - duplication of
ureter
7
Dept of Urology, GRH and KMC, Chennai.

8. ❖FACTORS INVOLVED
1. RET
2. FGFR
3. AT2R
4. GDNF
❖PROGAMMED CELL DEATH / APOPTOSIS – BRANCHING &
NEPHROGENESIS
8
Dept of Urology, GRH and KMC, Chennai.

9. HISTOLOGY
9
Dept of Urology, GRH and KMC, Chennai.

10. only two muscular layers
in this segment
UPPER URETER LOWER URETER
increased thickness of the
urothelium and additional
muscular layer.
UPPER URETER - More prone to injuries
10
Dept of Urology, GRH and KMC, Chennai.

11. COURSE IN ABDOMINAL PART :
• Downward continuation of renal pelvis
• Descend anterior to psoas major
• Cross ventral surface of transverse
processes of L3-5
• Passes anterior to the genitofemoral
nerve, & at its midpoint passes under the
gonadal vessels
• Enter pelvis by crossing in front of the
bifurcation of the CIA at the pelvic brim in
front of the SI joint. 11
Dept of Urology, GRH and KMC, Chennai.

12. RELATIONS OF ABDOMINAL PART
12
Dept of Urology, GRH and KMC, Chennai.

13. COURSE IN PELVIS :
MALE :
• Follows the course of the IIA
• Runs downward, backward,
& laterally along the greater
sciatic notch.
• Opposite to the ischial spine -
turns forward & medially to
reach the base of the UB
13
Dept of Urology, GRH and KMC, Chennai.

14. • The vas deferens relation
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Dept of Urology, GRH and KMC, Chennai.

15. 15
Dept of Urology, GRH and KMC, Chennai.

16. PELVIC RELATIONS OF THE URETER IN FEMALE :
• Forms the posterior limit of the
ovarian fossa.
• Entering the parametrium of the
broad ligament, crosses under the
uterine vessels “water under the
bridge” ,
• 1 -4 cm lateral to the cervix to reach
the anterior aspect of the vagina
before joining the bladder.
• Run anteromedially about 1 cm above
the lateral vaginal fornix
16
Dept of Urology, GRH and KMC, Chennai.

17. 17
Dept of Urology, GRH and KMC, Chennai.

18. INTRAMURAL URETER :
•Length - 1.2 to 2.5 cm
•Terminal ureter is enveloped by a
muscular layer, the Waldeyer sheath
•The Waldeyer muscle bundles of the
ureter coalesce with those of the
detrusor muscle . 18
Dept of Urology, GRH and KMC, Chennai.

19. RADIOLOGIC ANATOMY OF URETER :
• Three segments
• Proximal - From origin, down to the upper border
of the sacroiliac joint,
• Middle - lying over the sacrum,
• Distal - from the lower border of SI joint to its
entry into the bladder,
• Entire length of the ureter - rarely seen in a single
film of CTU
19
Dept of Urology, GRH and KMC, Chennai.

20. ENDOSCOPIC ANATOMY OF URETER
❑Retrogradely
• Ureter courses anterolaterally as it goes along the lateral pelvic wall
• Angulates posteriorly (after crossing the pelvic brim)
• Once the cystoscope is inside the bladder neck, the trigone can be
seen as a raised, smooth triangle.
• The apex of that triangle is situated at the bladder neck, and its base
is formed by the interureteral ridge or Mercier’s bar, extending
between the two ureteric orifices. 20
Dept of Urology, GRH and KMC, Chennai.

21. • The interureteral ridge is more prominent in males than females.
• The ureteric orifices are symmetrically located along it, approximately
1 to 2 cm from the midline.
• The normal ureteric orifice may appear as a volcano or a cone shaped
• However, it might look like a slit that can be identified with only
meticulous examination
21
Dept of Urology, GRH and KMC, Chennai.

22. • ureteral narrowing areas at the pelvic brim and UPJ are identified
endoscopically by being stenotic and relatively nondistensible.
• The pulsating iliac vessels could be seen endoscopically as the ureters
cross the pelvic brim
• The UPJ could be identified endoscopically during its frequent
opening and closing.
• The UPJ merges into the wider and more dependent part of the renal
pelvis.
22
Dept of Urology, GRH and KMC, Chennai.

23. • during ureteroscopy, the tidal volume could be decreased to minimize
renal excursions during respiration
• In the renal pelvis, the flexible ureteroscope first faces the ostia of the
major calyces, which look like circular openings separated by carinae.
• Then the flexible ureteroscope enters a long tubular infundibulum
that branches into the minor calyces.
• These infundibula usually connect the ostia of major calyces with
their apex
23
Dept of Urology, GRH and KMC, Chennai.

24. • For a flexible ureteroscope to pass from the axis of the upper ureteral
segment to the axis of the lower infundibulum, it should deflected
140 (104 to 175) degrees at the ureteroinfundibular angle .
• A circular muscle layer extends around the base of the papilla to help
expel urine jets from papillary ducts.
• The renal papillae appear endoscopically as protruding discs
surrounded by calyceal fornices, paler in color than the pink friable
epithelium covering the papillae
24
Dept of Urology, GRH and KMC, Chennai.

25. Endoscopic anatomy:
• Ureteric orifices @ UVJ – 5cm apart(full
bladder) ; 2.5 cm apart (empty)
• Merciers bar- more prominent in males
• Configuration of ureteric orifice:
• Higher the grade
• More lateral location
Reflux
25
Dept of Urology, GRH and KMC, Chennai.

26. Blood supply of Ureter :
Travel longitudinally in the Peri-ureteral adventitia.
ARTERIAL SUPPLY
UPPER URETER RENAL
AORTA
GONADAL
MID URETER CIA
GONADAL
LOWER URETER CIA
IIA
SUPERIOR VESICAL
26
Dept of Urology, GRH and KMC, Chennai.

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Dept of Urology, GRH and KMC, Chennai.

28. VENOUS DRAINAGE
• Venous drainage parallels arterial.
• abdominal part - renal and gonadal veins.
• mid- and distal ureters - common and internal iliac veins.
28
Dept of Urology, GRH and KMC, Chennai.

29. LYMPHATIC DRAINAGE
Lymphatic drainage:
• Lymphatic plexus within muscular &
adventitia
• LEFT RIGHT
• Para-aortic LNs Paracaval, Interaorto-caval
UPPER
• Common iliac LNs
MID
• Common iliac
• Internal iliac
• External iliac
LOWER
29
Dept of Urology, GRH and KMC, Chennai.

30. URETERAL INNERVATION
• 1. Sympathetic - from T12–L1 spinal segments through
RENAL,
AORTIC, &
HYPOGASTRIC plexuses.
• 2. Parasympathetic - S2–S4 via
Pelvic Splanchnic nerves.
❑ PERISTALSIS – independent of nerve supply
30
Dept of Urology, GRH and KMC, Chennai.

31. SITES OF ANATOMICAL
NARROWINGS/CONSTRICTIONS :
• 1. At the PUJ - approx 5 cm away from the
renal hilum. (12 Fr)
• 2. At the pelvic brim where it crosses the
common iliac artery. (12 Fr)
• 3. At the UVJ (3-10 Fr)
• Intramural ureter – narrowest
• (3-4 mm)
31
Dept of Urology, GRH and KMC, Chennai.

32. PHYSIOLOGY OF URETER
32
Dept of Urology, GRH and KMC, Chennai.

33. INTRODUCTION
33
Dept of Urology, GRH and KMC, Chennai.

34. CONTENT
• CELLULAR ANATOMY
• ELECTRICAL ACTIVITY
• CONTRACTILE ACTIVITY
• MECHANICAL PROPERTIES
• ROLE OF NERVOUS SYSTEM IN URETERAL FUNCTION
• URINE TRANSPORT 34
Dept of Urology, GRH and KMC, Chennai.

35. CELLULAR ANATOMY
❖Functional unit – smooth muscle cell
(L= 250- 400 um, D= 5-7 um)
❖DOUBLE LAYER CELL MEMBRANE
❖NUCLEUS
❖MITOCHONDRIA – POWER HOUSE
❖ENDOPLASMIC RETICULUM – Calcium STORAGE
❖Contractile proteins
35
Dept of Urology, GRH and KMC, Chennai.

36. ELECTRICAL PROPERTIES
❖RMP – ( -33 to -70 Mv ) Determinant - K ions
❖AP – primary event in the conductance of the peristalstic impulse >>>
ureteral contraction
CELL STIMULATION
DEPOLIRIZATION
TP
AP
36
Dept of Urology, GRH and KMC, Chennai.

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Dept of Urology, GRH and KMC, Chennai.

38. CELL STIMULATION
LOSS OF PREFFERTIAL PERMEABILITY TO K
MORE PERMEABILITY TO CA
FAST L-type CA channels
ACTION POTENTIAL
Slow rate of upstroke of AP >> slow conduction velocity
38
Dept of Urology, GRH and KMC, Chennai.

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Dept of Urology, GRH and KMC, Chennai.

40. ❖PACEMAKER POTENTIAL & ACTIVITY
• Electrical activity in cell – external stimulus / spontaneously >> pacemaker cells (
opening and slow closure of voltage activated L-type Ca. channels )
LOCATION
Multicalyceal system
Unicaleceal system
pelvicalyceal border to UPJ Near pelvicalyceal border
40
Dept of Urology, GRH and KMC, Chennai.

41. • LATENT PACEMAKER – THROUGHT URETER
• ICC LIKE CELLS
➢ Not a primary pacemaker cells
➢ Provide electrical conduction from pacemaler cells to typical smooth
muscle cells in renal pelvis and ureter
➢ Act as pacemaker cells & trigger contraction in absence of
pacemaker cells
41
Dept of Urology, GRH and KMC, Chennai.

42. ❖PROPAGATION OF ELECTRICAL ACTIVITY
➢Ureter acts as functional syncytium
➢Electrical activity arises proximally and conducted distally from cell to cell
through intermediate junctions
➢Gap junctions – electrical coupling and electrochemical coupling ( exchange
ions & small molecules)
➢Conduction velocity in ureter – 2- 6 cm / sec
42
Dept of Urology, GRH and KMC, Chennai.

43. CONTRACTILE ACTIVITY
43
Dept of Urology, GRH and KMC, Chennai.

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Dept of Urology, GRH and KMC, Chennai.

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Dept of Urology, GRH and KMC, Chennai.

46. 46
Dept of Urology, GRH and KMC, Chennai.

47. ❖Second messengers
Mediate functional response to hormones, NT, other agents
c AMP
c GMP
Ca+
IP3
Diacylglycerol
47
Dept of Urology, GRH and KMC, Chennai.

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Dept of Urology, GRH and KMC, Chennai.

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Dept of Urology, GRH and KMC, Chennai.

50. • A-adrenergic & cholinergic agonist ----------increase ca-----increase contraction
Agonist –receptor complex ++++++++++ Phospholipase-C Protein kinase- C
Phosphatidylinositol 4,5 biphosphate
IP-3 & DAG
50
Dept of Urology, GRH and KMC, Chennai.

51. MECHANICAL PROPERTIES
❖FORCE LENGTH RELATION
• Express the relation between the force developed by muscle
when it is stimulated under isometric condition & resting length
of muscle at the time of stimulation
• Ureter is viscoelastic structure
• The resting/contractile force developed at any given length
depends on the direction in which the change in length is
occuring & on the rate of length change ( HYSTERESIS) 51
Dept of Urology, GRH and KMC, Chennai.

52. • URETER SHORTENS– CONTARCTION FORCE GREATER THAN
RESTING FORCE
• URETER STRETCH – RESTING FORCE INCREASES
If the length is kept constant at its new longer length after a
stretch, changes occur that result in a decrease in the resting
force (stress relaxation )
52
Dept of Urology, GRH and KMC, Chennai.

53. ❖PRESSURE-LENGTH-DIAMETER RELATION
• Ureteral muscle fibres are arranged in longitudinal, circumferential
and spiral configuration
• Longitudianal & Diametral Deformation Of Ureter Are Interrelated
• CREEP – After the application of intaluminal pressure, the ureter
increase in both length and diameter.
53
Dept of Urology, GRH and KMC, Chennai.

54. ROLE OF NERVOUS SYSTEM IN URETERAL FUNCTION
• URETER – Syncytial type of smooth muscle without descrete NMJ.
• Ureteral peristalsis can occur without innervation proof –
1) persistence of peristalsis after transplantation or denervation
2) spontaneous activity in isolated in-vitro ureter
3) Normal antegrade peristalsis continues after reversal of segment
of ureter in-situ
so, nervous system has only modulatory role in ureteral peristalsis
54
Dept of Urology, GRH and KMC, Chennai.

55. PNS
• M2/3 muscarinic receptor – distal & intravesical portion
❖Cholinergic agonists ( Ach/mecholyl/ carbachol/bethanecol ) >> M3
- Increased frequency and force of contraction
❖Anti-Cholinesterases ( neostigmin /physostigmin)
❖Parasympathetic blocking agents (Atropin/ propantheline/
methanthelin)>> inhibition of ureteral activity ( effects are frequently
minimal and inconsistent )
55
Dept of Urology, GRH and KMC, Chennai.

56. SNS
• Ureter contains excitatory a-adrenergic & inhibitory b-adrenergic fibre
❖ADRENERGIC AGONIST
• Agents that activate a-adrenergic receptor (NE/Phenylephrine) >>
stimulate ureter & renal pelvic >> contraction ….a1d > a1a > a1b
• Agents that activate b-adrenergic receptor
(isoproterenol/orchiprenaline) >> inhibits ureter & renal pelvic >>
relaxation….b1/2/3
56
Dept of Urology, GRH and KMC, Chennai.

57. ❖ADRENERGIC ANTAGONIST
1. A-adrenergic antagonist (tamsulosin) -inhibits contarctility of ureter
>> relaxation
2. B- adrenergic antagonist ( propranolol) – block or attenuate the
inhibitory effect of b-adnergic agonists ( isoproterenol ) >>
contraction of ureter
57
Dept of Urology, GRH and KMC, Chennai.

58. URINE TRANSPORT
❖PHYSIOLOGY OF UPJ AND PROPULSION OF URINARY BOLUS
Frequency of calyceal & renal pelvis contraction >>> upper ureter (
relative block of electrical activity at PUJ.
IN RENAL PELVIS PRESSURE EXTRUSION OF URINE IN URETER
URETERAL CONTRACTION PRESSURE >>>> RENAL PELVIS PRESSURE
58
Dept of Urology, GRH and KMC, Chennai.

59. • Resting pressure ------- 0-5 cm H20
• Superimposed ureteral contractions ------20-80 cm H20
• Ureter as tubular structure
• LAPLACE EQUATION
• pressure = TENSION X WALL THICKNESS
RADIUS
59
Dept of Urology, GRH and KMC, Chennai.

60. URINE TRANSPORT
❖EFFECT OF DIURESIS ON URETERAL FUNCTION
• Increased flow rate
INITIALLY – INCREASED PERISTALTIC FREQUENCY
INCREASE IN BOLUS VOLUME
MAX. FREQUENCY
60
Dept of Urology, GRH and KMC, Chennai.

61. URINE TRANSPORT
❖ EFFECT OF BLADDER FILLING & NEUROGENIC VESICAL
DYSFUNCTION ON URETERAL FUNCTION
PRESSURE WITHIN BLADDER DURING STORAGE PHASE IS OF
PARAMOUNT IMPORTANCE IN DETERMINING EFFICACY OF URINE
TRANSPORT ACROSS VUJ
INTRAVESICAL PRESSURE > 40 CM H20---------URETER DECOMPENSATE
61
Dept of Urology, GRH and KMC, Chennai.

62. URINE TRANSPORT
❖PHYSIOLOGY OF VUJ
62
Dept of Urology, GRH and KMC, Chennai.

63. URINE TRANSPORT --SUMMARY
63
Dept of Urology, GRH and KMC, Chennai.

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Dept of Urology, GRH and KMC, Chennai.

65. NUMERICALS
• INTRAVESICAL PRESSURE > 40 CM H20---------URETER DECOMPENSATE
• Resting pressure ------- 0-5 cm H20
• Superimposed ureteral contractions ------20-80 cm H20
• Conduction velocity in ureter – 2- 6 cm / sec
• RMP – ( -33 to -70 Mv ) Determinant - K ions
65
Dept of Urology, GRH and KMC, Chennai.

66. • Length - 22-30 cm (Adults) ;
6.5-7.0 cm (Neonates)
• Diameter = 1.5- 6.0 mm.
66
Dept of Urology, GRH and KMC, Chennai.