Page 167 - Bladder Dysfunction in the Context of the Bladder-Brain Connection - Ilse Groenendijk.pdf

SUMMARY
The field of functional urology includes functional disorders of the lower urinary tract (LUT), consisting of the bladder, its sphincters and the pelvic floor muscles. The physiol- ogy of the LUT with its peripheral and central innervation is explained in introductory chapter 1 of this thesis. Furthermore, different disorders of the LUT with their symptoms and the diagnostics used are summarized. Relevant diagnostics include objective and subjective outcome measurements. Objective outcomes are measurements such as the number of voids per day or the post void residual. Subjective outcome measurements, usually in the form of a questionnaire, are designed to report patient’s perceptions, such as the symptom bother and health-related quality of life. Additionally, in this chapter the working mechanism of dynamic brain imaging is explained, in particular the work- ing mechanism of functional MRI (fMRI). Lastly, the available therapies for the subset of disorders are discussed, ranging from conservative, pharmacological to invasive treat- ments. It is emphasized, despite an increasing quality and amount of evidence in this field, there is a lack of knowledge on pathophysiology, diagnostics and therapies. This thesis aimed to investigate potential diagnostic tools in the field of functional urology and to improve objective and subjective outcome measurements.
The first part of this thesis reviews the present knowledge on brain control of the LUT and describes the usage of high-resolution 7T fMRI as a possible diagnostic tool in the field of functional urology. The brain areas involved in the innervation of the LUT were further defined, and we concluded that ultra-high field fMRI is a suitable technique to investigate brain areas involved in LUT control in individuals.
Chapter 2 describes a systematic review and meta-analysis which aimed to gener- ate an overview of the brain areas involved in motor control of the LUT. Following a systematic search of the literature, 5718 publications were screened on relevance, of which in total 19 studies were included. Of these 19 studies, eleven investigated pelvic floor muscle contractions (PFMC) and eight micturition. All given coordinates of active clusters following the execution of these tasks were extracted by two authors inde- pendently. Using these coordinates, a coordinate-based meta-analysis was performed in the form of an activation likelihood estimation (ALE) analysis. ALE analysis uses the included coordinates as a spatial probability distribution to create a ‘mean distribution’. To investigate PFMC, a total of 113 coordinates were entered, derived from 170 subjects. The results showed clusters in the primary motor cortex, supplementary motor areas, cingulate gyrus, frontal gyrus, thalamus, supramarginal gyrus and the cerebellum. In the micturition ALE analysis, we entered 98 coordinates of a total of 107 subjects. It revealed clusters in the pontine micturition center, periaqueductal grey, cingulate gyrus, frontal gyrus, insula and ventral pons. When comparing the results of PFMC to those of micturi- tion, we found that these two motor tasks of the LUT are innervated by distinct brain
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Summary and Nederlandse samenvatting 165