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Background: Individuals with Rett syndrome (RTT) are notoriously reliant on the use of eye gaze as a primary means of communication. Underlying an ability to communicate successfully via eye gaze is a complex matrix of requirements, with an intact oculomotor system being just one element. To date, the underlying neural and motor pathways associated with eye gaze are relatively under-researched in RTT.Purpose: This study was undertaken to plug this gap in knowledge and to further the understanding of RTT in one specific area of development and function, namely oculomotor function.Material and Methods: The eye movements of 18 girls and young women with RTT were assessed by electronystagmography (ENG). This tested their horizontal saccadic and smooth pursuit eye movements as well as optokinetic nystagmus and vestibulo-ocular reflex. Their results were compared with normative data collected from 16 typically developing children and teenagers.Results: Overall, the individuals with RTT demonstrated a range of eye movements on a par with their typically developing peers. However, there were a number of difficulties in executing the ENG testing with the RTT cohort which made quantitative analysis tricky, such as reduced motivation and attention to test materials and low-quality electrode signals.Conclusions: This study suggests that individuals with RTT have an intact oculomotor system. However, modifications should be made to the ENG assessment procedure to combat problems in testing and add strength to the results. Further investigation into these testing difficulties is warranted in order to inform such modifications. [ABSTRACT FROM AUTHOR]

Background An adolescent girl had isolated abnormal downward gaze and oculovestibular (cold caloric) testing during propofol administration, prompting concern for brainstem abnormality. Patient An otherwise healthy 16-year-old girl presented after an intentional hanging. Brainstem reflexes were normal except that both eyes exhibited tonic downward gaze on initial examination. After propofol was suspended for 30 minutes in order to evaluate her level of responsiveness, her eyes normalized to midposition from tonic downward gaze. With reinitiation of propofol, the eyes returned to the former downward position. C-collar stabilization prohibited the usual oculocephalic (doll's eyes) evaluation. Right-sided cold water instillation resulted in right eye exodeviation to the right with minimal medial movement of the left eye to the right. After left-sided cold water instillation, the left eye deviated downward with minimal medial deviation of the right eye. She was extubated and off sedatives within 48 hours of admission, and normal ocular motility returned. Conclusions This patient exhibited abnormal ocular motility and cold caloric response with single-agent propofol exposure. The remainder of her cranial nerve examination was normal, and her normal imaging studies and prompt resolution led us to suspect a propofol effect. Physicians should be aware of the pharmacologic alterations of ocular motility and cold caloric testing when propofol is administered. [ABSTRACT FROM AUTHOR]