Chapter 9 Flashcards
What of the term for horizontal latent strabismus with the eye deviating outward?
Exophoria.
Exo- eye is turned outward, phoria- deviation is only present when fixation is interrupted
What term refers to the movements of both eyes together?
Versions.
When testing Extraocular Motility, the first step is to check the eye movements together. If there is as an abnormality, observation of each eye separately (duction) is necessary to determine which eye is the cause
What must a patient have to develop stereopsis?
Binocular Vision.
Stereopsis is the component of depth perception retrieved through binocular vision and cannot be present if the patient is monocular
What horizontal eye movement turns the eye inward?
Adduction.
Adduction is performed by the medical rectus 1st degree and all other muscles except lateral rectus 3rd degree
The third cranial nerve controls what muscle?
Medial Rectus.
The 3rd cranial nerve (oculomotor nerve) also controls the superior rectus, inferior rectus, and inferior oblique muscles
What strabismus is detected, how is the amount of deviation qualified?
Prism and alternate cover test.
The amount of prism necessary to neutralize an abnormal alignment measures the deviation in prism diopters (the refractive power of the prism)
Proper execution of the Titmus Stereopsis Test requires the patient to wear what type of spectacles?
Light-polarizing spectacles.
In some parts of the photographs, the images are horizontally displaced. The polarizing filters make those parts come forward off the page
The 6th cranial muscle supplies which extraocular muscle?
Lateral Rectus.
The 6th or Abducens nerve controls the lateral reactus which is responsible lateral abduction.
The trochlear nerve powers which extraocular muscle?
Superior oblique.
The 4th or trochlear nerve controls the superior oblique which is responsible for inclocytorsion 1st, depression 2nd, and Adduction 3rd degree
