Oculomotor abnormalities in children with Niemann-Pick type C

Area of Science:

• Ophthalmology
• Neurology
• Genetics

Background:

• Niemann-Pick type C (NP-C) is a rare, progressive, recessive neurodegenerative disorder.
• Oculomotor abnormalities, particularly gaze palsy, are characteristic of NP-C.
• Previous studies focused on adult NP-C patients, leaving a gap in pediatric oculomotor assessment.

Purpose of the Study:

• To investigate oculomotor degeneration in pediatric NP-C patients using high-resolution eye tracking.
• To compare eye movement parameters between neurological, pre-neurological NP-C patients, and healthy controls.
• To assess the sensitivity of eye-tracking measures for detecting early disease-related changes and monitoring progression.

Main Methods:

• High-resolution video-based eye tracking was employed to record monocular vertical and horizontal eye movements.
• Key saccade parameters analyzed included onset latency, peak velocity, and curvature.
• Data from 2 neurological NP-C, 3 pre-neurological NP-C patients, and 77 healthy controls were compared.

Main Results:

• NP-C patients exhibited selective impairments in vertical saccade peak velocity and curvature, with slower velocities and increased curvature.
• These oculomotor abnormalities were more pronounced in neurological NP-C patients than in pre-neurological ones.
• Abnormal saccade curvature and slowed downward saccades were detected in both NP-C groups, indicating sensitivity prior to clinical manifestation.

Conclusions:

• High-resolution eye tracking is a sensitive and objective method for measuring NP-C disease severity and neurological onset in children.
• Eye-tracking can detect NP-C-related oculomotor changes before they are clinically observable.
• This technology holds promise for monitoring disease progression and evaluating therapeutic interventions in NP-C.