Non-nystagmus hyperkinetic eye movement disorders
Francesco Certo1,2, Giulia Salvucci1, Chiara Casellato1
1Clinical Neurology and Movement Disorders Units, San Paolo University Hospital, University of Milan, ASST Santi Paolo e Carlo, Via Antonio di Rudinì 8, Milan, 20142, Italy.
Summary
Non-nystagmus hyperkinetic eye movement disorders (NHEMD) are often missed but crucial to identify as some are treatable. This review guides recognition, diagnosis, and treatment of these complex ocular motility issues.
Area of Science:
- Ophthalmology
- Neurology
- Neuro-ophthalmology
Background:
- Non-nystagmus hyperkinetic eye movement disorders (NHEMD) are frequently overlooked compared to nystagmus.
- NHEMD can stem from various causes including muscle/nerve issues, brain lesions, systemic diseases, or functional factors.
- Early recognition of NHEMD is vital as some manifest treatable underlying conditions.
Purpose of the Study:
- To provide a practical guide for recognizing specific NHEMD.
- To assist in selecting appropriate diagnostic tests for NHEMD.
- To outline treatment strategies for various NHEMD.
Main Methods:
- Categorization of NHEMD by anatomical lesion location and pathophysiology.
- Discussion of disorders originating from extraocular muscles/oculomotor nerves.
- Analysis of NHEMD linked to brainstem/brain lesions and functional causes.
Main Results:
- Detailed review of NHEMD, starting with peripheral causes like superior oblique myokymia and ocular neuromyotonia.
- Exploration of central causes including ocular bobbing, opsoclonus, and tonic downward gaze deviation.
- Consideration of functional NHEMD and associations with neurological disorders like Parkinson's disease and blepharospasm.
Conclusions:
- This review offers a comprehensive reappraisal of hyperkinetic disorders of eye motility.
- It emphasizes the importance of understanding NHEMD for accurate diagnosis and management.
- The structured approach aids in differentiating and managing diverse NHEMD.
