Background
The alternations of brain responses to strong desire to void during a urodynamic study were unclear. The present study aims to identify the functional brain network's topologic property changes evoked by a strong desire to void in healthy male and female adults with synchronous urodynamics using a graph theory analysis.
Methods
The bladders of eleven healthy males and eleven females were filled with a catheter in a specific infusion and withdrawal pattern. The resting-state functional magnetic resonance imaging (fMRI) of the enrolled subjects was scanned under the empty bladder and strong desire to void states. Automated anatomical labeling (AAL) atlas was used to identify the ninety cortical and subcortical regions. Pearson's correlation calculations were performed to establish a brain connection matrix. A paired t-test (P < 0.05) and Bonferroni correction were applied to identify the significant statistical differences in topologic properties between the two states, including small-world network property parameters [gamma (γ) and lambda (λ)], characteristic path length (Lp), clustering coefficient (Cp), global efficiency (Eglob), local efficiency (Eloc) and regional nodal efficiency (Enodal).
Results
Significantly, a small-world network property was presented in all subjects. The significantly decreased Cp, Lp, Eloc, and increased Eglob were detected in the female subjects under the strong desire to void. Notably, the increased Enodal was observed in left the orbital part of middle frontal gyrus and inferior frontal gyrus, right middle temporal gyrus, median cingulate and middle occipital gyrus, and bilateral inferior parietal gyrus, gyrus rectus and supramarginal gyrus. In the male subjects, the increased Enodal presented in right frontal operculum and medial superior frontal gyrus, left supplementary motor area and the bilateral supramarginal gyrus. On the other hand, the significant decreased Enodal in female subjects was detected in the bilateral calcarine fissure and surrounding cortex, lingual gyrus, and fusiform gyrus. The decreased Enodal in male subjects presented in right inferior occipital gyrus and thalamus.
Conclusions
In the study, there were potential gender differences in functional brain network's topologic property alternations in response to the strong desire to void under a repetitive infusion and withdrawal pattern.