Outline
Practical Methods To Quantify Eye Movements After Neuro Insult
1) Review of components of the oculomotor system and their normal function
a) Fixational Eye Movement Control
b) Pursuits and Tracking Control
c) Vestibulo-Optokinetic Eye Movements
2) Methods for measurement of oculomotor performance
a) Methods Available
i) Gross Observation
ii) Corneal Reflex techniques
iii) Electro-oculography
iv) Photographic / Videography Techniques
v) Visuoscopy and Biomicroscopy .
vi) Subjective Methods involving Patient Responses
(1) Number Calling Tests
(2) After Image feedback
b) Fixational Eye Movement Control
i)
Visual Attention / Time On Task
ii) Gaze Fixational Control/ Nystagmus
iii) Saccades
(1) DEM Testing
(2) Visagraph II
c) Pursuits and Tracking Control
i) Nine Positions of Gaze
ii) Role of targets and Speed (Pursuit Gain Measures)
iii) Standardized Pursuit Tracking Tests
iv) OKN techniques
d) Vestibulo-Optokinetic Eye Movements
i) Head-Eye movements
(1) Head Shaking tests
(2) Dolls Head Testing
3) Oculomotor changes associated with acquired brain injury
a) Nystagmus
b) Delayed Pursuit Gain
c) Paralysis -paresis of eye movements
d) Disturbed reading
e) Brain stem damage
a. internuclear ophthalmoplegia
b.
c.
d.
e.
f.
g.
horizontal gaze paresis
vertical gaze paresis
Parinaud syndrome
abnormalities of accommodation, convergence, and fusion
cerebellar lesions
vestibular system dysfunctions
4) Use of these measures for rehabilitation.
a) Feedback Methods
b) Setting Behavioral objectives and baselines
i) Passive / Active Treatment
(1) Vision Therapy
(2) Occluders
(3) Prisms /Lenses
c) Examples :
i) Fixational Dysfunctions
ii) Tracking and Pursuit Dysfunctions
iii) Vestibulo-ocular Dysfunctions