[Urodynamics of neurogenic lower urinary tract disfunction caused by spinal cord injury].

OBJECTIVES: To improve the diagnosis of patients with neurogenic lower urinary tract dysfunction and to provide a basis for proper selection of rehabilitation methods.

METHODS: The urodynamics was tested with Assend Urodynamic Instrument in 220 patients with spinal cord injury. Of these patients, 100 received regular cystometrograrhy (CMG) and urethal pressure profile (UPP) test, and the remaining patients were measured by bladder/ external sphincter pressure profile. The detrusor pressure, maximum detrusor voiding pressure, and maximum urethral pressure were recorded. The date from the tests were processed with SPSS 8.0 (independent samples T test).

RESULTS: The maximum urethal pressure (83 +/- 39) cm H(2)O (1 cm H(2)O = 0.098 kPa) and maximum voiding detrusor pressure (12 +/- 10) cm H(2)O were lower in coda-equina group than in other groups (t = 2.096,P < 0.05). The group with different spinal cord injury had almost an equal ratio of low bladder compliance (51.2%, 52.4% and 50% separately). Statistical differences were found between complete injury and incomplete injury in each group(t = 1.023, P > 0.05). In bladder/external sphincter cystometry, urethral pressure profile could be classified into four types.

CONCLUSIONS: The maximum urethral pressure and maximum pressure of detrusor contractile were lower in the cauda-equina injury group than in other groups. The cauda-equina injury group showed a lower incidence of detrusor sphincter because most of these patients were incompletely injured. The features of urethral pressure profile in bladder/external sphincter cystometry resulted from the abnormal contraction of external sphincter and periurethral striated muscles.