SPECT imaging of the dopamine transporter with [I-123]-beta-CIT reveals marked decline of nigrostriatal dopaminergic function in Parkinson's disease with urinary dysfunction

We studied a correlation of urinary dysfunction with nigrostriatal dopamine rgic deficit in Parkinson's disease (PD) by single-photon emission computed tomography (SPECT) imaging of dopamine transporter with [I-123]-2 beta -ca rbomethoxy-3 beta-(4-iodophenyl) (beta -CIT). Eleven patients were enrolled in the study, including four men and seven women, with a mean age of 64 ye ars. Seven patients had urinary symptoms 1-5 years after the onset of motor disorder, which included nighttime frequency in six, urinary retardation i n four, daytime frequency in one and urge urinary incontinence in one. Usin g a SPECT camera, the ratio specific to nondisplaceable [I-123]-beta -CIT u ptake, designated as 'striatal V3' was obtained in the caudate, anterior an d posterior putamen 24 h after the tracer injection. The striatal V3 was co mpared in patients with and without urinary dysfunction, and between men an d women, using unpaired Student's t-test. Correlation of motor dysfunction and duration of illness with urinary dysfunction, was also analyzed. In the patients, there was a reduction of [I-123]-beta -CIT binding in the striat um on both sides, particularly in the putamen contralateral to the affected body side. The striatal V3 of the caudate (p < 0.01, Rt; p < 0.05, Lt), an terior putamen (p < 0.05, Rt) and posterior putamen (p < 0.05, Rt) in patie nts with urinary dysfunction was significantly reduced than those without u rinary dysfunction. No sex difference was seen in reduction of [I-123]-beta -CIT binding. Urinary dysfunction in PD was more common in patients with h igher Unified Parkinson's Disease Rating Scale (UPDRS) score, higher Hoehn- Yahr grade, but not in those with longer duration of disease, although ther e was no statistical significance. It is likely that our results reflect th e association of urinary dysfunction and degeneration of the nigrostriatal dopaminergic cells in PD. (C) 2001 Elsevier Science B.V. All rights reserve d.