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Updated: May 22, 2025
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Assessment of Static Graviceptive Perception in the Roll-Plane using the Subjective Visual Vertical Paradigm
Published on: April 28, 2020
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The von Gräfe sign measurement.
Juliana A Guimaraes1, Denny M Garcia1, Antonio Augusto V Cruz1
1Department of Ophthalmology, School of Medicine de Ribeirão Preto, University of São Paulo, Ribeirao Preto, Brazil.
Orbit (Amsterdam, Netherlands)
|March 13, 2025
Summary
Patients with Graves
Area of Science:
- Ophthalmology
- Endocrinology
Background:
- Graves' ophthalmopathy (GO) is an autoimmune condition affecting the eyes.
- Upper eyelid retraction is a common manifestation of GO.
Purpose of the Study:
- To quantify upper eyelid saccadic movements in patients with Graves' upper eyelid retraction.
- To compare saccadic movement amplitudes and velocities between patients with GO and healthy controls.
Main Methods:
- Customized software was used to measure lid saccade amplitude and velocity.
- ImageJ software quantified eyelid retraction.
- Orbital CT scans measured levator palpebrae superioris muscle dimensions.
Main Results:
- Patients with GO showed a significantly higher margin-reflex distance (MRD1) compared to controls.
- The levator palpebrae superioris muscle was enlarged in GO patients.
- Absolute lid movement amplitude and velocity did not differ between groups.
Conclusions:
- Despite enlarged levator palpebrae superioris muscle, its relaxation is not impaired in inactive GO.
- Downward lid movement amplitude does not fully compensate for retraction in GO patients.
- The von Gräfe sign is a relative measure of lid elasticity, not an absolute loss.
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