prelim chap 7 and 8 Flashcards
purpose of case history taking: (4)
- establish caring relationship w px, showing compassion, empathy and respect
- to gather information about chief complaint, visual function, ocular and systemic health, risk factors and lifestyle
- to begin the process of differential diagnosis
- to begin the process of px education
to identify gross abnormalities of the eye and adnexa
external observation
under ocular motility and binocular vision test (7 )
cover test
corneal reflex test
near point of convergence test
near point of accommodation
motility tests
tests of pupillary functions
tests of stereopsis
this test depends on retinal focus
done to all patients after case history taking
visual acuity
decreases retinal blur and increases patient’s depth focus
if done, acuity will improve if there’s no ocular abnormalities
pinhole va test
measures patient’s ability to change focus of lens in response to near stimulus
amplitude of accommodation
significant test for the assessment of macular cone and optic nerve function
color vision test
- assess the presence of magnitude of phoria or tropia (strabismus)
- assess presence or absence of motor fusion
cover test
determine magnitude of the demand placed on a px’s fusional vergence system
cover test
measure px’s fine depth perception through his ability to fuse stereoscopic targets
stereopsis
assess px’s flat fusion ability at distance and near
detect small unilateral central scotoma
worth 4 dot
indicated when stereopsis is less that 40 seconds of arc
used for differential diagnosis of unilateral decreased VA
worth 4 dot
determine patient’s convergence eyes while maintaining fusion
near poimt convergence
determine positions of visual axes of 2 eyes under binocular conditions at near
used to identify strabismus when other more precise tests cannot be used
hirschberg and krimsky
assess symmetry of binocular fixation by comparing the brightness of red-reflex in each eye
screen for the presence of refractive error
bruckner
used to screen for strabismus, anisometropia, media opacity, posterior pole anomalies in young children
bruckner
assess patient’s ability to perform conjugate eye movement’s
extraocular motility test
assess afferent and efferent neurological pathway responsible for pupillary function
pupils
screen for previously unnoted visual field defects
only for substantial field loss
screening for visual field / finger counting vf
determine the distance in millimeters between the entrance pupils of two eyes for a given viewing distance
interpupillary distance
DPA diagnostic pharmaceutical agents
- topical anesthetics
- mydriatics
- cycloplegics
- used to anesthesized the cornea prior to tonometry gonioscopy
- reduce permeability or nerve cell membranes to sodium ions
topical anesthetics
first anesthetic drug
cocaine
- proparacaine: ophthaine, ophthetic, alcaine. 0.5%, agent of choice
- benoxinate: dorsacaine. 0.4%. contraindicated to cardiac, thyroid and allergies
- tetracaine: potocaine. 0.5%. causes CNS stimulation, convulsion and depression
