BACKGROUND AND PURPOSE: Guillain-Barre syndrome (GBS) is an acute demyelinating polyneuropathy with various clinical features. Optic neuritis occurs in rare cases. In this study we determined the incidence and patterns of visual evoked potential (VEP) abnormality in GBS in association with ophthalmologic findings. METHODS: Thirty-two patients with a diagnosis of GBS were included in the study. The correlation between pathologic VEPs and categories of neurologic deficit and electrophysiological findings were examined statistically. RESULTS: The patients ranged in age from 19 to 77 years. Five cases (16%) had abnormal VEPs. All five of these patients exhibited increased P100 latency differences between the two eyes. Other abnormalities were prolonged p100 latency, increased interocular amplitude difference, and distorted p100 configuration. Pathologic signs on ophthalmologic examination were observed in 80% of patients with abnormal VEPs. VEP abnormality was never present in pure axonal forms. There was no significant correlation between pathologic VEP and cerebrospinal fluid protein level or categories of neurologic deficits. CONCLUSIONS: Involvement of the optic pathways is not a frequent finding in GBS. When present it is always asymmetric and generally accompanied with pathologic findings on ophthalmologic examination. VEPs may be abnormal in different clinical variants of GBS, and especially in demyelinating forms.
Axons ; Evoked Potentials, Visual ; Eye ; Guillain-Barre Syndrome ; Humans ; Incidence ; Neurologic Manifestations ; Optic Neuritis ; Polyneuropathies

Objectives: The aim of this study is to evaluate the remedial effect of continuous positive airway pressure (CPAP) therapy on neurocognitive function in obstructive sleep apnoea (OSA) patients. Methods: The cognitive impairment in OSA patients was evaluated with Montreal Cognitive Assessments (MoCA) before and after CPAP therapy. The study assessed 54 patients who were diagnosed with OSAS seen at the neurology clinic of the Trakya University Medical Faculty. They were given MoCA the day of diagnosis, after one day of CPAP therapy, and after three months of CPAP therapy. Results: MoCA scores before treatment showed a statistically significant correlation between disease severity and abstract thinking (Correlation coefficient: 0.270±0.048). There was no significant difference between MoCA scores before treatment and after one day of CPAP therapy (p=0.244). However, there were significant improvements in MoCA scores after three months of treatment, when compared to scores from before treatment and after one day of therapy (p<0.001). Conclusions: CPAP treatment may improve cognitive function in OSA patients. MoCA is an effective and simple tool for evaluating cognitive function.