Neuroselective current perception threshold evaluation of bladder mucosal sensory function.
OBJECTIVE
To evaluate human bladder mucosal sensory function by neuroselective Current Perception Threshold (CPT) measures from healthy and neuropathic bladders.


METHODS
Eight healthy volunteers and 38 patients with urinary symptoms underwent conventional urodynamic tests including water-filling cystometry and ice water test. Standardized neuroselective CPT measures were obtained from the left index finger and the mucosa of the posterior bladder wall. Three different CPTs were obtained from each test site using a constant alternating current sinusoid waveform electrical stimulus presented at 2000Hz, 250Hz and 5Hz stimulation frequencies, which could selectively reflect the functions of the large myelinated fibers (A-beta-fiber), the small myelinated fibers (A-delta-fiber), and the unmyelinated fibers (C-fiber), respectively.


RESULTS
As the determination of CPT values on the finger skin, the CPT values in the bladder could be determined using the neuroselective measures in all patients but three who had no sensory response (absence of sensation) caused by complete spinal injury. In the 8 patients with detrusor hyperreflexia due to incomplete spinal cord injury (supra-sacral lesion), the bladder CPT value (4.0+/-1.9) at 5Hz was significantly lower (p<0.01) than that in the controls (26.2+/-17.7). In the neurogenic bladders determined to be underactive (n=11, including post pelvic surgery, post infra-sacral level spinal cord injury and diabetes patients), the higher CPT values of bladder mucosal sensory functions were found at 5Hz (p<0.05), 250Hz (p=0.07), and 2000Hz (p<0.05) compared to the controls.


CONCLUSIONS
Quantitative neuroselective measurement of CPT values in the human bladder mucosal function was feasible. Hypersensitivity or hyposensitivity of the urinary sensory function could be determined using the CPT values in comparison to control. The quantitative neuroselective estimation of the bladder sensory functions in different types of sensory peripheral nerve fibers may contribute to the appropriate selection of therapeutic strategy in patients with urinary sensory dysfunction.
Ukimura
Osamu
O
Department of Urology, Kyoto Prefectural University of Medicine, Kawaramachi-Hirokoji, Kyoto, 602-8566, Japan. akimura@koto.kpu-m.ac.jp
Ushijima
So
S
Honjo
Hisashi
H
Iwata
Tsuyoshi
T
Suzuki
Kei
K
Hirahara
Naoki
N
Okihara
Koji
K
Mizutani
Yoichi
Y
Kawauchi
Akihiro
A
Miki
Tsuneharu
T
D000328:Adult; D004566:Electrodes; D004867:Equipment Design; D006801:Humans; D008297:Male; D008875:Middle Aged; D009092:Mucous Membrane / Q000294:innervation / Q000503:physiopathology; D012677:Sensation; D012684:Sensory Thresholds; D001743:Urinary Bladder / Q000294:innervation / Q000503:physiopathology; D001745:Urinary Bladder Diseases / Q000503:physiopathology*; D001750:Urinary Bladder, Neurogenic / Q000503:physiopathology