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Purpose: To review the roles of the different vascular beds nourishing the inner retina [retinal ganglion cells (RGCs)] during normal development of the human eye, using our own tissue specimens to support our conclusions., Methods: An extensive search of the appropriate literature included PubMed, Google scholar, and numerous available textbooks. In addition, choroidal and retinal NADPH-diaphorase stained whole mount preparations were investigated., Results: The first critical interaction between vascular bed and RGC formation occurs in the sixth to eighth month of gestation leading to a massive reduction of RGCs mainly in the peripheral retina. The first 3 years of age are characterized by an intense growth of the eyeball to near adult size. In the adult eye, the influence of the choroid on inner retinal nutrition was determined by examining the peripheral retinal watershed zones in more detail., Conclusion: This delicately balanced situation of RGC nutrition is described in the different regions of the eye, and a new graphic presentation is introduced to combine morphological measurements and clinical visual field data.

The vestibular system has more connections with and influence on higher cortical centers than previously thought. These interactions with higher cortical centers and the phenomena that they elicit require a structural intact cerebral cortex. To date, little is known about the role and influence of the vestibular system on one's body experience. In this study we show that caloric vestibular stimulation (CVS) in healthy participants has an effect on the perceptive component of one's body experience. After CVS all participants showed a statistically significant difference of thigh width estimation. In contrast to previous studies, which demonstrated an influence of CVS on higher cortical centers with an intact cerebral cortex both the cognitive and affective component of body experience were not effected by the CVS. Our results demonstrate the influence of the vestibular system on body perception and emphasize its role in modulating different perceptive-qualities which contributes to our body experience. We found that CVS has a limited influence on one's conscious state, thought process and higher cortical functions.

Many patients with postural tachycardia syndrome (PoTS) suffer from fatigue, daytime sleepiness, and sleeping disturbances. The objective of this study was to compare subjective and objective sleep quality of PoTS patients with a group of healthy controls. All patients completed a Pittsburgh Sleep Quality Index questionnaire and the Epworth Sleepiness Scale. The patients sleep architecture, heart rate, and heart rate variability (HRV) measurements were taken during one night at the sleep laboratorium. All data was collected at the Sleep Unit, at Helios Klinikum Wuppertal. Thirty-eight patients diagnosed with PoTS were compared to 31 healthy controls, matched in age and gender. Patients with PoTS reached significantly higher scores in sleep questionnaires, which means that they were more sleepy and had a lower sleep quality. Polysomnography showed a significantly higher proportion of stage 2 sleep. The results of HRV analysis in different sleep stages confirmed changes in autonomic activity in both groups. PoTS patients, however, showed a diminished variability of the low-frequency (LF) band, high-frequency (HF) band, and LF/HF ratio in different sleep stages. It can therefore be gathered that PoTS could be considered as potential differential diagnosis for sleep disturbances since PoTS patients had a subjective diminished sleep quality, reached higher levels of daytime sleepiness, and showed a higher proportion of stage 2 sleep. PoTS patients showed furthermore a reduction of LF/HF ratio variability in different sleep stages.

Non-motor symptoms are now commonly recognized in Parkinson's disease (PD) and can include dysautonomia. Impairment of cardiovascular autonomic function can occur at any stage of PD but is typically prevalent in advanced stages or related to (anti-Parkinsonian) drugs and can result in atypical blood pressure (BP) readings and related symptoms such as orthostatic hypotension (OH) and supine hypertension. OH is usually diagnosed with a head-up-tilt test (HUT) or an (active) standing test (also known as Schellong test) in the laboratory, but 24 h ambulatory blood pressure monitoring (ABPM) in a home setting may have several advantages, such as providing an overview of symptoms in daily life alongside pathophysiology as well as assessment of treatment interventions. This, however, is only possible if ABPM is administrated correctly and an autonomic protocol (including a diary) is followed which will be discussed in this review. A 24-h ABPM does not only allow the detection of OH, if it is present, but also the assessment of cardiovascular autonomic dysfunction during and after various daily stimuli, such as postprandial and alcohol dependent hypotension, as well as exercise and drug induced hypotension. Furthermore, information about the circadian rhythm of BP and heart rate (HR) can be obtained and establish whether or not a patient has a fall of BP at night (i.e., "dipper" vs. non-"dipper"). The information about nocturnal BP may also allow the investigation or detection of disorders such as sleep dysfunction, nocturnal movement disorders, and obstructive sleep apnea, which are common in PD. Additionally, a 24-h ABPM should be conducted to examine the effectiveness of OH therapy. This review will outline the methodology of 24 h ABPM in PD, summarize findings of such studies in PD, and briefly consider common daily stimuli that might affect 24 h ABPM.