TY - JOUR
T1 - The relationship between two types of upper eyelid movements
T2 - Saccades and pursuit
AU - Falcão, Marcele F.
AU - Malbouisson, Jorge Mario C.
AU - Cruz, Antonio Augusto V.
AU - Messias, André
PY - 2008/6
Y1 - 2008/6
N2 - PURPOSE. To establish the relationship between upper eyelid saccades and upper eyelid pursuit movements METHODS. Upper eyelid saccades and periodic sinusoidal upper eyelid pursuit movements were recorded in a sample of controls and patients with Graves upper eyelid retraction. A video-computerized system was used to register both types of movements that accompanied 60° of eye rotation across the upper and lower hemifields. The forced harmonic oscillator model was used to fit saccadic and pursuit movements. RESULTS. Mean mid-pupil eyelid distance for the Graves patients (6.6 ± 1.1 mm) was significantly higher than for the controls (4.6 ± 0.8 mm; t = 7.18; P < 0.00001). Despite the difference in the upper eyelid resting position, saccades and pursuit eyelid movements of both groups were extremely well fitted by underdamped solutions and steady forced solutions of the harmonic oscillator model, respectively. For the controls, the amplitude of the pursuit movements was well correlated with the upward and downward saccades. The amplitude of the eyelid movements of the Graves patients (saccades and pursuit) was significantly reduced compared with that of the controls. CONCLUSIONS. Saccadic and pursuit movements of the upper eyelid can be described by the harmonic oscillator model. In healthy subjects and Graves patients, the amplitude of pursuit lid movements is correlated to the saccade amplitude. Pursuit eyelid movements are more difficult to register than saccades, and their measurements do not allow clear separation of the relaxation and contraction properties of the upper eyelid retractors.
AB - PURPOSE. To establish the relationship between upper eyelid saccades and upper eyelid pursuit movements METHODS. Upper eyelid saccades and periodic sinusoidal upper eyelid pursuit movements were recorded in a sample of controls and patients with Graves upper eyelid retraction. A video-computerized system was used to register both types of movements that accompanied 60° of eye rotation across the upper and lower hemifields. The forced harmonic oscillator model was used to fit saccadic and pursuit movements. RESULTS. Mean mid-pupil eyelid distance for the Graves patients (6.6 ± 1.1 mm) was significantly higher than for the controls (4.6 ± 0.8 mm; t = 7.18; P < 0.00001). Despite the difference in the upper eyelid resting position, saccades and pursuit eyelid movements of both groups were extremely well fitted by underdamped solutions and steady forced solutions of the harmonic oscillator model, respectively. For the controls, the amplitude of the pursuit movements was well correlated with the upward and downward saccades. The amplitude of the eyelid movements of the Graves patients (saccades and pursuit) was significantly reduced compared with that of the controls. CONCLUSIONS. Saccadic and pursuit movements of the upper eyelid can be described by the harmonic oscillator model. In healthy subjects and Graves patients, the amplitude of pursuit lid movements is correlated to the saccade amplitude. Pursuit eyelid movements are more difficult to register than saccades, and their measurements do not allow clear separation of the relaxation and contraction properties of the upper eyelid retractors.
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U2 - 10.1167/iovs.07-1308
DO - 10.1167/iovs.07-1308
M3 - Article
C2 - 18362108
AN - SCOPUS:47249148367
SN - 0146-0404
VL - 49
SP - 2444
EP - 2448
JO - Investigative Ophthalmology and Visual Science
JF - Investigative Ophthalmology and Visual Science
IS - 6
ER -