Eye movement abnormalities in normal pressure hydrocephalus: a video-oculographic study.

Area of Science:

• Neuroscience
• Ophthalmology
• Neurology

Background:

• Eye movement dysfunction is common in neurodegenerative diseases.
• Normal pressure hydrocephalus (NPH) presents diagnostic challenges due to overlap with parkinsonism and dementia.
• Video-oculography (VOG) can explore ocular dysfunction in NPH.

Purpose of the Study:

• To comprehensively investigate ocular dysfunction in NPH patients using VOG.
• To identify potential VOG biomarkers for NPH diagnosis and cognitive assessment.

Main Methods:

• 42 NPH patients and 76 healthy controls (HC) underwent VOG assessment.
• Evaluated reflexive saccades (amplitude, peak velocity, latency) and fixation tasks (square wave jerks - SWJ).
• Correlated VOG data with clinico-radiological features.

Main Results:

• NPH patients showed significantly increased saccadic latency (33.8%) compared to HC.
• No significant differences in saccadic amplitude, peak velocity, or SWJ between NPH and HC groups.
• Increased saccadic latency correlated with cognitive deficits, particularly phonemic fluency and executive functions.

Conclusions:

• Saccadic latency is a VOG biomarker for cognitive deficits in NPH patients.
• VOG offers a rapid, quantitative method for assessing cognitive status in NPH over time.
• Unaffected saccadic amplitude and velocity may aid in differentiating NPH from neurodegenerative parkinsonian syndromes.