1. Revision of essential basic urological science
Derek J P Rosario
Senior Clinical Lecturer and Honorary Consultant Urologist
Academic Urology Unit, University of Sheffield
DJ Rosario, KL Potts, HH Woo and CR Chapple.
Department of Urology, Royal Hallamshire Hospital, Sheffield, U.K.
AMBULATORY URODYNAMICS IN THE BASHFUL VOIDER
Aims of study
The inability to voluntarily initiate a void during a videocystometrogram is occasionally seen in younger men with lower urinary tract symptoms (LUTS). Interpretation of this phenomenon is rendered difficult by the absence of reported pressure-flow data in this group of patients. Possible reasons for this ‘bashfulness’ that have been put forward are the presence of previously unsuspected bladder neck dyssynergia, occult neuropathy or merely an accentuation by the conditions of the investigation of the normal physiological inhibitory mechanisms that exist in higher organisms but not in animals. Given such diversity of opinion we established this study using home uroflowmetry and ambulatory urodynamics to provide a urodynamic diagnosis in a group where standard videocystometrography had failed to provide a voiding study.

2. A few questions…
Does continence serve a purpose?
What do I understand about the autonomic nervous system?
Is continence a conscious or unconscious act?
Why should I learn about continence?

3. What is the Lower Urinary Tract?
The bladder (reservoir)
The bladder neck
The prostate gland (in the man)
The urethra and urethral sphincter
Outlet

4. Female Male

5. Function of the Lower Urinary Tract
To convert the continuous process of excretion (urine production) to an intermittent, controlled volitional process (micturition).

6. Essential features of the normal lower urinary tract
Low pressure, insensible storage of urine of adequate capacity.
Prevent leakage of the urine stored.
Allow rapid, low-pressure voiding at an appropriate time and place.

7. How is this achieved? Control mechanisms.
Innervation of the lower urinary tract.
Biophysical properties of the bladder.

8. Glomerular filtration and the production of urine
a. Mean arterial pressure mmHg
b. progressive reduction along nephron
c. Collecting system pressure 3 – 10 mmHg (5-15 cmH2O)

9. Synergic lower urinary tract action
Voiding
Detrusor contraction sufficient to effect bladder emptying
Switch from voiding to storage
Urethra contracts
Detrusor contraction switched off

10. Autonomic nervous system

11. The autonomic plexus

12. LUT – differences from other visceral functions
CNS control
Only two modes – storage or voiding
Voluntary control
Learned behaviour
Maturation of the nervous system

13. Innervation of the urinary sphincter

15. Cholinergic transmission

16. Neural Control of the LUT
Parasympathetic (Cholinergic) S3-5
Drive detrusor contraction
Sympathetic (Noradrenergic) T10-L2
Urethral contraction
Inhibit detrusor contraction
Non-adrenergic non-cholinergic

17. Fowler et al 2008

18. Control of micturition – cortex and brain-stem
Frontal cortex
Septal Region
Hypothalamus
Pontine micturition centre

19. Fowler et al 2008

20. Fowler et al 2008

21. Neural Organisation

22. Storage

24. Macroscopic ureter peritoneum Dome of bladder rugae Detrusor
Ureteric orifice
Trigone
Prostate
Bladder neck
verumontanum

25. Compliance

26. Urothelium (Transitional epithelium)
Highly specialised
Stratified 3 –7 cells thick
Basal, intermediate and umbrella (facet)
Barrier function - ‘water-tight’?
Able to fold and unfold
Highly vascular
Sensory function

27. Urothelial arrangement

28. Empty Bladder

29. Full Bladder

30. Muscularis detrusor No gap junctions No discrete layers
Packed together with confluent basal laminae

31. Blood vessels
Ability to elongate with minimal increase in resistance to flow
Blood flow is reduced by distension
In poorly compliant bladders, large reduction in blood flow - ? Reperfusion injury

32. Summary
Complex neural circuitry controlling lower urinary tract with ‘predictable’ consequences depending on level of damage.
Common clinical problem, so understanding of underlying principles essential.