bladder and its dysfunction

1. I NERVATION OF BLADDER AND ITS DYSFUNCTION

2. OVERVIEW Anatomy and physiology CNS centers Arcs and loops Spinal tracts Basic concepts of neurourological function Reflexes Dysfunction Pharmacological management

3. Anatomy and physiology Upper urinary tract dysfunction is rare due to neurological disease Lower urinary tract is richly supplied with both autonomic and somatic nervous system

4. Bladder anatomy Three anatomical layers Inner mucosal layer Muscular middle layer Outer and inner longitudinal layer Middle circular layer Outer adventitial layer Functinally bladder is divided in to parts Body Trigone

5. Receptors of the bladder Parasympathetic ( musacrinic ) Sympathetic Dual action Beta adrenargic Alpha adrenergic

6. CNS centers PONS Pontomesencephalic reticular formation Afferents from bladder receptors of distension Sphincter detrusor synergesia Reticulospinal tracts spincter and detrusor centers of the spinal cord

7. Cortex, basal ganglia and cerebellum Paracentral lobule involved in voluntary initiation of micturition and inhibition of reflex voiding Lesions results in frequency and urgency Direct control of voluntary micturition influencing the onufs nucleus through CST Pontine micturition center

8. Spinal cord centers Sympathetic anteriomediolateral gray column thoracolumbar cord T9-L1 Parasympathetic nuclei intermediolateral region of sacral cord S2-S4 Onuf’s nucleus anterior horn of sacral cord

9. Arcs and Loops Supra spinal arc Parasympathetic afferent input from tension receptor in the bladder wall to pontine micturition centers Reticulospinal tracts to centers to sacral cord 3 to 4 yrs of age voiding is a reflex process Lesions above the brain stem manifested clinically by frequency and urgency with preserved detrusor sphincter synergesia

10. Sympathetic nervous system arc Efferent sympathetic innervation T9-L1 through ventral routes, sympathetic ganglia in the para vertebral chain preaortic and parvertebral chains Touch, pain, and temperature from bladder through spinothalamic tract

11. Parasympathetic nervous system arc Efferents originate in the sacral cord travels throgh ventral spinal roots and pelvic nerves and joins with sympathetic nerves to create a large autonomic plexus Proprioceptive information of bladder sensation and pain through posterior columns and spinothalamic centers to PMC and supraspinal centers

12. Pudendal system arcs Efferent somatic innervation of ext sphincter from the onufs nucleus through pudendal nerves Afferent carry exteroceptive and proprioceptive sensation from pelvic floor Afferent fibers from the ext sphincter and pelvic floor synapse with pudendal motor neurons in ventral horns of the spinal cord and helps in voluntary and reflex activity

13. LOOPS Loop 1 Pathways between frontal cortex, basal ganglia, thalamic nuclei, cerebellum and pontomesencephalic reticular formation Predominantly inhibitory Interruption leads to loss of volitional control of micturition reflex – uninhibited detrusor CVA, brain tumor, head injury, multiple sclerosis, Parkinson’s disease.

14. LOOP 2 Sensory afferent neurons from detrusor – posterior and lateral columns, ‘’ long routing’’ in spinal cord - pontomesencephalic portion in brain stem Efferent neurons from micturition center travel down in reticulospinal tract ‘’ long routing’’ to detrusor without any synapse in spinal cord Required to establish an adequate magnitude and duration of detrusor reflex to accomplish complete bladder emptying

15. contd Interruption – hyper- reflexic detrusor – unable to produce a voluntary voiding contraction Spinal cord trauma, multiple sclerosis, spinal cord tumor, arachnoiditis

16. LOOP 3 Detrusor and pudendal motor nuclei and their interneurons in sacral cord Coordination between detrusor contraction and striated urethral sphincter relaxation during voiding

17. LOOP 4 Motor cortex in frontal lobe – traverse via pyramidal tract in lateral columns of spinal cord, synapse on pudendal sphicter nucleus. Voluntary control over striated muscle of the urethral sphincter during bladder storage and voiding

18. Spinal tracts Cortico s pinal tract Reticulospinal tract Spinothalamic tract Posterior columns

19. Basic concepts of neurourological function Two phases Low pressure insensanate filling and storage of urine Efficient evacuation under voluntary control Filling and storage of urine Passive filling phase initial phase occurs till proxim al urethral pressure > exceeds the bladder Continence reflex phase bladder pressure > urethral pressure

20. Frontal micturition center by bladder distension enhances sympathetic activity and external sphincter Micturition Normal urinary voiding is voluntary disinhibition of pontine and sacral reflex activity in response to bladder distension

21. REFLEXES Superficial anal reflex Anal reflex or anal wink consists contraction of anal sphincter in response to stroking or pricking the skin of perianal region Inferior haemarhoidal nerve (S2-S5) Caudaequina or conus medullaris lesions Bulbocavernosus reflex Stimulating the skin of glans or penis response is felt by placing a gloved finger in rectum

22. Neurogenic bladder dysfunction 5 types (2 UMN; 3LMN) Uninhibited Reflex Autonomous Motor paralytic Sensory paralytic

23. Nomenclature Urgency is the complaint of a sudden and compelling desire to pass urine that is difficult to defer. Urge incontinence is the complaint of involuntary leakage accompanied by urgency. Leakage may range from drops to soaking Retention bladder is unable to empty itself to a point that there is over 100 cc's (3.5 ounces) of urine left over in the bladder after urinating*

24. Uninhibited bladder Lesion affecting the second frontal gyrus and the pathways leading from it down to the pontine centre Frontal lobe tumours , parasagittal meningiomas , anterior communicating artery aneurysms, normal perssure hydrocephalus, Parkinson’s disease and multisystem atrophy

25. Uninhibited bladder Features are: Urgency at low bladder volumes ( detrusor hyperreflexia ) Sudden uncontrollable evacuation No residual urine - little risk of infection If severe intellectual deterioration occurs urine may be passed at random, without appropriate concern.

26. Spinal bladder Damage to spinal cord by trauma, tumor, multiple sclerosis Fullness is not appreciated Intravesical pressure may only be indicated by sweating, pallor, flexor spasms, dramatic rise in blood pressure Reflex emptying without warning Incomplete evacuation may improve with practice and may be performed at will if massaged and suprapubic pressure applied Detrusor – sphincter dyssynergia . Evidence of bilateral pyramidal lesion – enhanced reflexes and extensor plantar response Bladder is small and contracted, can hold maximum of 250ml

27. Autonomous bladder( subsacral lesions) Damage to sensory and motor components in cauda equina or pelvis Cauda equina lesions, Pelvic surgery, pelvic malignant lesions, spina bifida and high lumbar disc lesions MRI or myelogram is obligatory to exclude high disc lesions

28. Autonomous bladder( subsacral lesions) contd Features Continual dribbling incontinence Considerable residual urine with high infection risk No sensation of bladder fullness- large atonic bladder May be associated with perineal numbness and loss of sexual function

29. Sensory bladder Similar to autonomous bladder Anatomical explanation is uncertain Primary problem is sensory denervation Ultimately overdistension , myogenic damage and contractile failure Rare disorders : Tabes dorsalis , SACD and Multiple sclerosis, Diabetes mellitus

30. Sensory bladder contd.. Features : Massive retention of urine in litres – high risk of infection Dribbling incontinence of sufficiently large volumes Voiding possible with considerable straining but evacuation is incomplete

31. Motor paralytic Areflexic detrusor Marked by painful distention Inability to initiate urination Difficulty initiating urination, straining, decreased size and force of stream, interrupted stream, and recurrent urinary tract infection.

32. Pharmacological methods Urinary retention Cholinergic agents to increase detrusor motor function Bathnechol improves detrusor funtion particularly in denervation and selectively affects bladder and gut Alpha adrenergic blockers such as prazosin

33. Urinary incontinence Inhibition of detrusor activity and increase functional capacity of bladder Anticholinergics such as propanthaline Anticholinergic with smooth muscle relaxing properties such as oxybutinin TCA such as imipramine with anticholinergic activity

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