Cerebral control of bladder storage in patients with detrusor overactivity

To identify the brain areas that control bladder storage by technetium-99m hexamethylpropyleneamine oxime single-photon emission computed tomography (SPECT) with the Neurological Statistical Image Analysis software (NEUROSTAT) in patients with detrusor overactivity (DO).

SPECT scans were performed on 19 patients with DO. Eight patients with normal detrusor function, who had some storage symptoms of the lower urinary tract as the patients with DO, also had a SPECT scan, as controls. All the patients were male and right handed, and were scanned twice under two conditions: resting state and urine withholding state. NEUROSTAT was adopted to analyze the difference in brain--blood perfusion between groups and states. The results were displayed on Z score images at a significance threshold of P value of less than 0.05 with correction for multiple comparisons.

No region reached the significant threshold in comparison with patients with DO and normal detrusor function in resting state. Significant increases in tracer activity in the right inferior frontal gyrus and the right middle temporal gyrus during urine withholding state as compared with resting state in patients with normal detrusor function were observed. Among the regions, the right inferior frontal gyrus was distinctly prominent at both Z score and the extent. The regions that were significantly activated in patients with normal detrusor function did not reach a significant threshold during urine withholding in patients with DO.

The study indicated that the right inferior frontal gyrus and the right middle temporal gyrus, especially the right inferior frontal gyrus, played a role in the cerebral control of bladder storage, inhibiting the contraction of detrusor in urine storage.