Abstract
In urodynamics, cystometrogram (CMG) along with simultaneous external urethral sphincter electromyogram (EUS EMG) are recorded and they are helpful to diagnose complex neurogenic bladder dysfunctions such as detrusor-sphincter dyssynergia. In this thesis, the time series of EUS EMG is analyzed. Different phases (filling phase and voiding phase) of micturition and the difference caused by spinal cord injury in Wistar rats are thoroughly studied. The natural phenomenon is usually extremely complicated, nonlinear and difficult to be analyzed by traditional linear methods. In this thesis, the techniques are based on the concepts of modern nonlinear dynamical systems. They include the techniques of return maps, determinism test, recurrecnce plot, and correlation dimension. The analyzed results indicate that some regularities exist in the time series. For instance, the dimensions of attractor in voiding phase are lower in rats with spinal cord injury. So far there is no good explanation for it. In the future, further studies of nonlinear dynamics in the time series, and the synergistics between EUS EMG and CMG, are imperative. However, the most important one is to distill the crucial information from the time series. This will be helpful to better understanding of lower urinary urodynamics.