Shared Flashcard Set

Details

Binocular Vision
Acoomodation dysfunction/Strabismus
52
Other
Graduate
04/02/2009

Additional Other Flashcards

 


 

Cards

Term
Normal AC/A - Basic ESO
Definition
  • POOR direct/indirect NFV
  • diplopia not blur
  • Inc MEM
  • USU. HYPEROPES, maximize +
  • vert prism
  • add lenses moderately affective
  • **HORIZONTAL prism - better than for exos
  • occlude for amblyopia
  • VT
  • surgery
Term
Normal AC/A - Basic ESO Vision Therapy
Definition

phase 1: Near then distance, get feeling of divergence, normalize NFV and accomodation, Mag > speed

Phase 2: accurate NFV and PFV, speed>mag, Int distance

Phase 3: integrate artificial binocular accom. w/ vergences

Term
Normal AC/A - Basic EXO
Definition
  • If acute - usually Neurological
  • POOR direct/indirect PFV
  • Diplopia not blur
  • Dec. NPC; MEM variable
  • Optimal correction
  • Vertical prism
  • Added lenses, moderately affective, adjunct to VT
  • Occlude for amblyopia
  • VT*****
  • Horizontal prism - if VT not possible or failed; usu high phorias
  • Surgery
Term
Normal AC/A - Basic EXO Vision Therapy
Definition

Phase 1:Learn convergence, normalize PFV and NFV, Mag>speed

Phase 2: accurate NFV and PFV, speed>mag

Phase 3: artificial binocular accomodation with vergences

Term

Accomodative Dysfunction - Physiology/phrmacology

Definition
  • increase in power of lens to see objects @ near
  • Accom controlled by ANS - primarily the parasympathetic (fast-Ach), causes miosis, convergence via CNIII,
  • Sympathetic system inhibits accom (SLOW), dilates, use parasympatholytic and sympathomimetic (PE)
Term
Drugs that cause accomodative dysfunctions
Definition

Insuff/infacilty:

  • ANS (parasympatholytic/sympathomimetic)
  • Alcohol/weed
  • Phenothiazides
  • antihistmaines
  • CNS stimulants (ADD meds)
  • Artane (parkinsons)

Excess:

  • ANS (parasympathomimetic/sympatholytic)
  • Morphine
  • Digitalis (HR)
  • Sulfonamides/Carbonic ANhydrase inhib
Term
Tests of Accommodation
Definition
MAF, BAF, Amplitudes, NRA/PRA, Lag
Term
Accom XS and Conv XS
Definition
If ahve accom XS maybe eso bc over accomodation could drive the convergence system into overdrive
Term
classifications of Accomodative Dysfunction
Definition

1. Accom Insufficiency - ill-sustained, paralysis, unequal

2. accom excess

3. accom infacility

Term
Accomodative Insufficiency
Definition
  • dec in accom AMPS by >2 D based on expected for age
  • Linear dec till 40yo then rapid decline till final 1D
  • Ave: 18.5-1/3age
  • lowest: 15-1/4age
  • near complaints
  • dec PRA (accom and vergence)
  • fails MAF
  • may or may not fail BAF
  • may or maynot have large lag - depends on ptnts ability to access convergence
Term
subtypes of Accommodative Insufficiency
Definition

1. Ill-Sustained - NORMAL amps!, low PRA, fails - MAF on repeatitions, Large lag, ESO @near

2. Paralysis - pre-presbyopes, FRANK dec mono/binoc amps, Fails NRA/PRA bc starts with blur!, Large lag, Fails + and - facility

3. Unequal - Poor balance/adies/neurological, reduces ASYMETRIC amps, May PASS nra/pra, large ASYMETRIC lag, Fails MAF (+ and/or -)

Term
Accommodative Excess
Definition
  • accommodation exceeds demend
  • UNCORRECTED HYPEROPIA
  • spasm
  • PSUEDOMYOPE
  • accom hysteresis
  • CI - using accom to dec exo
  • idiopathic
  • Towards end of day near complaints, difficulty focus at distance (esp after near work)
  • NORMAL AA
  • poor + MAF
  • LOW lag
  • low NRA w/ norm BO
  • Maybe ESO w/ low BI to blur
Term
Accommodative Infacility
Definition
  • Difficult to focus at distance; no pattern!!
  • NORMAL AA
  • POOR + and - MAf
  • Normal Lag
  • Low PRA/NRA w/ NORMAL ranges
  • GREATEST PROBLEM W/ PRISM STEPS
  • NO PATHOLOGICAL CAUSES
Term
Accommodative Dysfunction TReatments
Definition
VTInsufficiencyExcessInfacility
Correct ametropia & BVYYY
Added lensesY, 53%N, crutchRare, crutch
OcclusionRare, unequal/pharmNN
VT (not organic causes)Y, 90%YY
PrismNNN
SurgeryNNN
Pharmacologic Cyclo help adapt to Rx 
Term
CycloVertical Symptoms
Definition

Ocular - Pulling, itching, asthenopia

Blur, Diplopia, Reading difficulty

Fatigue, Nausea, vertigo (esp car sickness)

Term

Cyclovertical Signs

Definition

Head turn, tip, tilt

Axis shift

CT - "prism adaptations"

secondary vertical - usu high exo

Term
Suspect a cyclovertical
Definition
  • High/Persistent symptoms w/ intact BV system
  • Low MAgnitude Strabismus
  • Refractory BV
  • Poor BI and BO, and really poor recovery
Term

Diagnostic Test for vertical

(DONT rely on any ONE test)

Definition
  • Maddox rod, Modified thorington, aniso
  • Von grafe
  • Fixation disparity, associated phoris - flash
  • Diagnostic occlusion - symptoms but NO signs
  • CT
Term

Diagnostic Test for Cyclos

(DONT rely on any ONE test)

Definition
  • Double maddox rod
  • Double maddox prism
  • saladin
  • CT of cyclo
  •  ophthalmoscope - see if macula is in bottom 1/3 of optive nerve, if too far up or down eye could be encylo or excyclo
Term
Therapy sequence for Cylcoverticals
Definition
  1. correct ametropia - esp large cyl
  2. prism
  3. added lenses
  4. therapuetic occlusion - acute/neuro diplopia
  5. VT for VERTICALS!!
  6. surgery, only if >15pd
Term
Perscribing prism for cycloverticals
Definition
  • rx weakest prism amount to resolve symptoms
  • case dependent on how much to rx
  • 1/5 of vertical vergence amplitude
  • flip prism technique, prism amount to make it equal on both choices
  • **FIXATION DISPARITY -fastest most reliable! if horizontal prism neutralizes FD - VT
  • No vert prism adaptation but there is LATENCY
  • put prism in for 20 mins, recheck, if find more put in more prism for another 20 mins, recheck if no more RX prism, if find more DONT Rx
Term

Defn of Strabismus

Definition

Loss of FUSION, w/ or w/o muscle alignment

Suppresion/diplopia can be 1st, 2nd, 3rd degree

Term
Alternate terms for Strabismus
Definition
  • Hererotropia/tropia
  • crossed/walleyed
  • Squint
  • lazy eye
  • manifest tropia
Term

Sprectrum of BV

Definition
  • Clear/single/comfortable/efficient/BV
  • Decreased Quality of Fusion (get last)
  • Decreased stability of Fusion
  • Abnormal AC/A relationship
  • Loss of Fusion with good monocular skills
  • loss of unilateral monocular skills (get first)
Term
Prevelance of Strabismus
Definition

prevalance - # cases in a pop @ 1 time

2-6% (5-15 million of 288 million US)

ET 3x more likely than XT in kids and young adults

XT more common in eldery and women

Term

risk factors or strabismus

Definition

>30%+4D uncorrected hyperopes by 3yo become ET

50% down syndrom

44% cerebral palsy

90% craniofacial dysostosis

genetics, 10x more likely, 23-70%

Term
reasons to develop strabismus
Definition
  1. CNS defects-prevent fusion, congenital, common in preemies, DS and CP, large angle 60-100pd
  2. Acuity defect-prevents feedback, ptosis, RE, cataract, maculopathy, ON defect
  3. Motor Defect-prevents alignment, muscle, orbit, or innervation defect
  4. AC/A and Vergence defect-
  5. Optical anomalies induced by refractive correction-extreme RE, anisometropia
Term
Purpose of description of strabismus
Definition

to classify

accurate documentation - audits and baseline

to plan management

Term

7 signs of Strabismus

Definition
  1. Direction - eso/exo/hyper/hypo
  2. Frequency - how often can occur
  3. Magnitude - prism diopters
  4. Laterality - R/L/Alt
  5. Comitancy - aniso, noncomitant
  6. Periodicity, AC/A - difference btwn dist and near
  7. Cosmesis
Term
purpose to classification
Definition

diagnosis

billing

prognosis

etiology

Term
classification schemes
Definition
  1. Time of onset: early aquired(4-6 mn) late acquired(2yrs)
  2. Mode onset: acute/ progressive/ constant/ intermittent
  3. Size: Microtrope(<10-15), mod (10-30), Large (>30)
  4. AOA - has gaps: infantile, acquired, secondary, adn micro eso and exo trope (8 classes) 
  5. ICD-9: follows money, doesnt have all trope options
  6. CEMAS-8: Ocular motor dysfunction, sensory, horizontal trope, horiz phorias, cyclovert trope, cyclovert phoria, accom dysfunct, nystagmus
  7. Other: direction, accom/refract, duane-white, Disease, pseudostrab (lid, inner canthus)  
Term
Components of Strabismus exam
Definition
  1. Patient Hx
  2. Dx sequence: RE/VA, alginment, fusion, visual efficiency, pathology
  3. Dx summary - prognosis
  4. Management plan
Term
Strabismus Cheif Complaint
Definition

Cosmesis

School/PCP

Parent observation

Diplopia-asthenopia

positive family history

second opinion

Term
Hirschberg test for strabismus
Definition
INACCURATE, +/- 11pd
Term
Krismsky test for strabismus
Definition

only slightly better than hirschberg, but is objective

prism bar in front of deviated eye, accuracy <10pd

unsed on infants to find out how much to cut muscle

 

 

Term
Bruckner test for strabismus
Definition

using oscope dial in to make face clear and look at both reflexes, supposed to be equal

if unequal, brighter reflex is strabismic eye

Term
Cover Test for detecting strabismus
Definition

UCT - detects

ACT - magnitude and direction

Unilateral uncover, only strab, watch for version adn vergence, alternating, intermittent

comtancy - feilding out

Term
Amblyoscope test for strabismus
Definition

Measures at optical infinity

Alternate Exclusion (ACT) - 2 images, one OD and one OS, alternatly occlude and move until no eye movements

Corneal light reflex (krimsky) - fixate OD adn move light on OS til reflection is 0.5mm nasal

Term
Abnormal tests with strabismus but wont DETECT:
Definition

stereopsis

worth dot

VA

Alt occlusion

Maddox rod

Vongrafe phorias

Term
charecteristics of non-commitant deviations
Definition

diplopia, cyclophoria

pastpointing-overcompensates, place object and ask ptnt to pt where its at, if recent ptnt will overcompensate, if long standing will be normal bc developed compensation

Spread of commitance-over time muscles begin to stropy, weaker antag muscle of paretic muscle evens out paralysis

Head posture/facial asymmetry

look at pictures

Term
defn/criteria of non-comitant
Definition

def:different phorias in different gazes

criteria: at least 5pd difference, can be mild/moderate/marked

can be phoria or tropia

paresis - underaction or overaction

Term

Non-Commitant Underactions

Definition

ocular restrictions: muscle damage, adhesions

mechanical anaomolies of insertion and ligaments may restrict

Paresis:neural, most common; blocked innervation

Term
Non-Commitant Overaction
Definition

primary - most common cause of overaction - usu obliques

secondary - not really etiology, common occurance, bc there is an underaction has to be an overaction

Term
Primary vs secondary angle of deviation
Definition

primary angle - smaller, normal eye is fixating, weak muscle

secondary angle - larger, defect eye fixating,

can get neutral CT, one eye neutral adn other is not - suspect paretic muscle!

Term
how Testing no commitant
Definition
occlude suspect eye and only measure that eye NOT both
Term
A/V patterns
Definition

changes in horizontal deviation on up &/or down gaze

A - >10pd inc in devergence in down gaze

V - >15pd inc in divergence in Up gaze (2x more common than A)

Term
Duanes Syndrome
Definition

non-commitant horizontal: type 1: more innerv to med rectus; type 2: retraction on adduction, more innerv to lateral rectus; type 3: retraction on adduction but more innerv to lateral rectus

paresis of abduct, adduct or both

congenital

assoc w/: torticollis/ hearing and facial-vertibral anomolies

Term
Browns syndrome
Definition
Restriction of Superior oblique, deficient elevation on adduction
Term
Disociated vertical Deviation (DVD)
Definition

not a true hyper or double hyper

DHD, DTD

assoc w/ latent nystagmus (upshoots on horizontal gaze)

Term
Classifications of non-commitance
Definition
  • AOA mechanical strabismus
  • CEMAS non-comm, eso and exo
  • CEMAS cyclovertical and special forms
  • cyclovertical of paretic origin
  • dissociated strabismus complex (DVD)
  • restrictive/mechanical
  • Neuro-myogenic strab
  • Special forms
Term
prognosis of strabismus
Definition

eso prognosis worse than exo

ARC worse than NRC

constant worse than intermittent

Term
defn of cured
Definition
  • bifoveal fixation in 99% ADL
  • clear vision, gen comfortable
  • bifixation in all gazes and a few cm NPC
  • reasonable corrective lenses and prism
  • stereopsis
Supporting users have an ad free experience!