None listed
Conditions
Brief summary
Many studies have demonstrated that the central cholinergic system is important in mediating cognitive processes of learning and memory. Nonetheless, many studies have supported the hypothesis of Central Nervous System cholinergic involvement in Myasthenia Gravis.More specifically, there is some evidence that Myasthenia Gravis has central cholinergic effects manifested by cognitive dysfunction. Hence, the aim of this study was to investigate with established psychophysiological methods such as pupillometry and concomitantly with the Mangina-Test, the hypothesis of Central Nervous System cholinergic involvement in patients with Myasthenia Gravis. All participants were informed about the study procedure and provided written informed consent and all the experiments were approved by the Ethical Committee of the AHEPA University Hospital based on the Helsinki Declaration.
Interventions
All subjects underwent pupillometric measurements. All participants were assessed on a single occasion only. Pupillary measurements were taken with a monocular and fully automated system.Participants remained for 2 min in darkness, and 5 flashes were administered afterwards (inter-stimulus interval was 30sec). Stimulus duration was 20 msec, and the luminance 24.6 cd/m2. Each eye was tested separately. The flash was placed at a distance of 30 cm from the eye.
Sponsors
Antonia Kaltsatou
Study design
Allocation
Non-randomised trial
Intervention model
Single group
Primary purpose
Diagnosis
Masking
Open (masking not used)
Eligibility
Sex/Gender
All
Age
34 Years to 69 Years
Healthy volunteers
No
Inclusion criteria
All patients were diagnosed with MG (mean time from the diagnosis was until the beginning of the study 2.9+/-0.2 years) using the established and diagnosis criteria. Specifically, their diagnosis was based on one hand on the clinical symptoms (fatigue during the day, etc), and on the other hand, on the laboratory findings (presence of positive antibodies for the AchR, positive response at the repeated stimuli test). Apart from these, MG patients showed an improvement of the muscle strength following the intake of edrophonium chloride and reacted positively to Mestinon. It was a key inclusion criterion that participants previously showed an improvement of the muscle strength following the intake of edrophonium chloride and reacted positively to Mestinon because from this we were sure that the Myasthenia Gravis Diagnosis was correct. All patients were free of any other neurological, ophthalmological, physical or mental disease and their visual acuity, corrected or not, were 20/20. Moreover, they had symmetrical pupils and no past history of ocular operations or diseases affecting the pupil and were not being treated at that time with anticholinergics, steroids, sympathomimetics, beta-blockers or other agents affecting the Pupil Light Reflex (PLR). Also, the basic precondition for participation was a mini mental score greater than or equal to 22. All measurements were performed between 09.00 and 10.00 hours after the participants had had a full eight-hour sleep.
Exclusion criteria
If MG patients do not show an improvement of the muscle strength following the intake of edrophonium chloride and reacted positively to Mestinon.
Outcome results
None listed