In recent years the brain-bladder control network has been visualized in different fMRI-studies. The role of the brainstem und suprapontine regions has been elucidated. Especially the pontine region and the periaqueductal gray as the central structures of the micturition circuit demonstrated well localized activations. It was time to transfer the paradigma to clinical relevant questions. Detrusor-Sphincter-Dyssynergia (DSD) is a common problem in patients with neurological diseases. Residual urine and consecutive urinary tract infections with the risk of kidney damage remains a problem. In the present study we compared the activation sites of patients with DSD with those of our previously published healthy control with special emphasis of the brainstem region.
Eleven patients with DSD participated in the study. fMRI imaging was performed at 3T (Siemens Magnotom trio, Erlangen, Germany). The participants had to either relax or contract the pelvic floor muscles to mimic voiding and interruption of the micturition process. Each instruction was followed by a control condition during which the subjects had to lay in the scanner waiting for the next instruction. Functional data were analyzed and visualized using Brain Voyager QX.
Both events induced strong and well located activations in the brainstem and suprapontine regions. The regions known from the healthy volunteers could have been demonstrated nicely. Interestingly, we detected a more dorsal activation in the pontine regions as well as more localized activations in the insula.
In patients with DSD we could show that the regions in the brainstem as well as those in more rostral areas could be visualized using fMRI. The main effects were comparable with the group of healthy volunteers. Interestingly, we detected the well known activation in the pontine region in the dorsal part, suggesting that the "L" region is more prominent in those patients. The more dominant insular activation might be a hint for the sympathetic mediated contraction of the urethral sphincter and the missing relaxation during the micturition process.