Neurogenic Bladder

William D. Steers

Introduction

When an abnormality of the nervous system triggers changes in continence, micturition, or urinary symptoms, the term “neurogenic bladder” is used. The urinary bladder and its outlet are unique among viscera because of their complex interplay of visceral and somatic systems in regulating the lower urinary tract (LUT) and the ability of emotions to affect visceral function.As might be expected, the neural regulation of the lower urinary tract differs from other organ systems in that these structures, although innervated by the autonomic nervous system, are under voluntary control. This duality of autonomic and somatic innervation is suited for switching from involuntary urine storage to voluntary elimination.This chapter provides a brief overview of the organization of the neural pathways and central sites influencing micturition and continence, catalogs those disorders linked to neurogenic bladder and pathology,and briefly outlines how neurogenic bladder disorders can be diagnosed and treated.

Examination and Diagnostic Tests

History and Physical Examination

Evaluating a patient with neurogenic bladder involves a detailed neurourologic history and focused neurologic exam.In addition to symptom

assessment, the onset and duration of symptoms, coexistent sexual and bowel complaints, and previous treatments for the urologic or neurologic condition should be obtained. The urologist can be instrumental in confirming a diagnosis or obtaining baseline LUT function prior to treatment. The neurourologic assessment at a minimum includes evaluating lower extremity motor function, lumbosacral dermatome sensation, and the bulbocavernosus reflex. This is not to exclude an overall neurologic evaluation and an appraisal of mental status which is crucial for designing a treatment regimen. An assessment of blood pressure (BP) should be made especially during symptoms suspicious of autonomic dysreflexia (AD). Supine and upright BPs are recorded to document whether orthostatic hypotension exists which suggests autonomic neuropathy.

Imaging

Imaging of the upper or lower urinary tract in the neurogenic bladder patient is used to assess whether hydronephrosis or calculi are present as well as sites of obstruction or reflux. Serum creatinine may be normal despite upper tract deterioration necessitating periodic renal imaging, especially in patients with clinical or urodynamic findings indicating a high risk for hydronephrosis. Imaging during urodynamics is also crucial to assess structural or functional abnormalities. Most notably, a voiding cystourethrogram can pinpoint the level of obstruction