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Parameters Used to Define Horizonal Gaze: A Systematic Review
Féthi Laouissat1, Sonia Ramos-Pascual2, Ankitha Kumble2
1Clinique Trenel, Sainte-Colombe, France.
Global Spine Journal
|March 19, 2025
Summary
This systematic review found 18 ways to measure horizontal gaze, but no single standard exists. Current methods show variability in results, highlighting the need for a reliable, standardized measurement for clinical use.
Area of Science:
- Ophthalmology and Vision Science
- Biomechanics and Kinesiology
- Medical Imaging and Measurement
Background:
- Accurate measurement of horizontal gaze is crucial for diagnosing and managing various neurological and musculoskeletal conditions affecting head and eye movement.
- Existing methods for quantifying horizontal gaze lack standardization, leading to potential inconsistencies in clinical assessment and research.
Purpose of the Study:
- To systematically review and summarize available parameters for measuring horizontal gaze.
- To report the typical values of these parameters in both patient and asymptomatic populations.
- To assess the reliability and inter-observer variability of the identified horizontal gaze measurement techniques.
Main Methods:
- A comprehensive literature search was performed on Medline and Embase databases using keywords 'horizontal gaze' and 'gaze line'.
- Included articles published between 2015 and 2023 that reported on horizontal gaze parameters.
- Data extraction focused on measurement parameters, their values in different populations, and reliability metrics.
Main Results:
- Eighteen distinct parameters for horizontal gaze measurement were identified across 26 included studies.
- McGregor's slope, C0-C2 angle, and chin brow vertical angle (CBVA) were the most frequently reported parameters.
- While inter-observer reliability was generally good to excellent, significant variations in measurements among asymptomatic individuals were observed across studies.
Conclusions:
- Despite the identification of numerous horizontal gaze parameters, a definitive gold standard is currently lacking.
- The observed variability in measurements across studies suggests limitations in the clinical relevance of current methods.
- There is a critical need to develop and validate a standardized, reliable gold standard for horizontal gaze measurement that incorporates anatomical landmarks and provides insights into compensatory mechanisms.
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