Page 168 - Bladder Dysfunction in the Context of the Bladder-Brain Connection - Ilse Groenendijk.pdf
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Chapter 9
areas, only showing overlap in the mid cingulate gyrus and the left thalamus. An im- portant consideration when interpreting the results of chapter 2 is the limited amount of data available for the ALE analysis. Moreover, it shows that more data is necessary on this topic to learn more about the physiology and subsequently the pathophysiology of diseases including motor control of the LUT. In this thesis the ALE analysis is used for the first time to investigate PFMC and the knowledge involved brain areas for specific tasks is increased.
To improve and enlarge data available on this topic, next to chapter 2, chapter 3 and chapter 4 report on our findings of 7T fMRI studies, during motor tasks and sensory tasks. We used group and individual analysis to investigate the brain areas involved in these tasks. The main goal of these studies was to investigate the applicability of 7T fMRI to study individual activity patterns involved in LUT control in the whole brain. For 7T fMRI to be suitable as potential diagnostic tool, significant results need to be available in individual patients.
Both chapters included 17 subjects. Data of four subjects could not be used due to motion artefacts. In chapter 3, subjects performed PFMC and tongue movements in the 7T MRI scanner. The latter task was chosen as mid-line control task. In chapter 4, tactile stimulation of the penile shaft was studied, with tactile stimulation of the feet served as control task. Data of both studies revealed that single subject results in the whole brain, were complementary to group results. An important finding of chapter 4 is the location of activation on the primary sensory cortex (S1) during tactile stimulation of the penile shaft. The study showed that the genitalia are represented in the hip region in S1 and not below the feet, as stated in earlier publications with group analysis in lower resolution MRI scanners.
The studies presented in the second part of this thesis aimed to investigate and im- prove both objective and subjective outcome measurements within functional urology. When a patient with overactive bladder does not respond to conservative or phar- macological therapies, a minimally invasive therapy known as sacral neuromodulation (SNM) can be considered. Before the lead and neuromodulator are implanted, SNM first need to be tested in a test-phase. The study presented in chapter 5 investigated whether urodynamic parameters show an acute effect on SNM in patients with overactive blad- der (OAB). There was a threefold rationale for this study. First, to increase knowledge on the working mechanism of SNM; second, to evaluate whether urodynamic parameters could be used instead of or complementary to this test-phase; and third, to investigate the usefulness of a ‘closed-loop feedback system’ in which SNM automatically activates when the bladder pressure increases. We found no acute effect of SNM on urodynamic parameters. This observation suggests that SNM primarily works via sensory pathways and not directly via motor pathways. This does not rule out the possible effects of a
closed-loop feedback system, as explained in the discussion of chapter 5.




























































































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