Visual Efficiency Diagnosis Flashcards
Recite the three basic steps of integrative analysis
1) compare individual tests to tables of expected findings 2) group the findings that deviate from expected 3) identify the syndrome based on steps 1 and 2
What are common signs and symptoms of vergence and accommodative anomalies?
blurred vision, headache, asthenopia, fatigue, diplopia, motion sickness, loss of concentration
Why do we need to diagnose vergence and accommodative anomalies as early as possible?
prevention of accommodative esotropia, prevention of decompensation into other strabismus, and prevention of academic/learning difficulties
What are the three categories of binocular anomalies?
Low AC/A, Normal AC/A, High AC/A
What categories of binocular anomalies do Duane-White classification fall under?
Low AC/A and High AC/A
What are low AC/A anomalies?
convergence insufficiency and divergence insufficiency
What are normal AC/A anomalies?
fusional vergence dysfunction, basic exophoria, basic esophoria
What are high AC/A anomalies?
convergence excess and divergence excess
What is convergence insufficiency?
exo N>D; exo at near > 4 ^; ortho or low exo at distance, receded NPC, reduced PFV (low BO); low AC/A
Which anomaly is often seen in early presbyopic patients when their accommodation decreases?
CI because they can’t compensate for convergence difficulty
What is the convergence insufficiency prevalence?
the most common of all non-strab BV disorders
How can you determine a pseudo-CI from a CI?
CI has problem with convergence, pseudo CI has accommodation problem– run CT through +1 and the pseudo CI will improve
What is a pseudo CI?
accommodative issue; reduced accommodation=less accommodative convergence
What presentation does a pseudo CI have?
greater XP at near, patient uses more PFV to maintain single vision resulting in a reduced ability to converge
What may a pseudo CI have that a true won’t?
low amps, high MEM, reduced (-) on facility
What is divergence insufficiency?
eso D>N, reduced BI at distance (NFV low), low AC/A, normal versions
What is the prevalence of DI?
least common and least studied, warning flag!
Why is a DI a warning flag?
must rule out pathology like brain stem tumors, vascular conditions, etc. especially in sudden onset, refer for MRI and check for divergence paralysis
Which anomaly is a red flag?
DI if sudden onset
What is convergence excess?
eso N>D, eso at near, ortho or low eso at distance, reduced NFV (BI), high AC/A
What is the prevalence of CE?
fairly common
What is divergence excess?
exo D>N, greater exophoria at distance than at near, may see IXT at distance, normal stereo at near, typically normal PFV, high AC/A
What divergence excess finding may throw you off?
normal PFV, this condition is often hidden until fatigue
Which anomaly can be found in conjunction with strabismus (XT)?
divergence excess
What is fusional vergence dysfunction?
reduced/tight PFV and NFV, normal AC/A, normal phoria at both distance and near, reduced vergence facility
Which anomaly is subtle and hard to diagnose?
fusional vergence dysfunction
What is basic esophoria?
normal AC/A and approximately same eso deviation at distance and near that is outside the norms, reduced NFV at both distance and near
What range of prism diopters is ok for comparing distance and near phorias of basic eso and exo patients?
4-5 prism diopters
What is basic exophoria?
normal AC/A with exo approximately the same at distance and near, reduced PFV at both distance and near
What percent of patients with exo deviations are basic exophores?
27.6%
What method do normative values of accommodative amplitude come from?
push-up
Which method of accommodative amplitude measurement is most reliable?
pull-away
Monocular accommodative findings can help differentiate between accommodative and binocular diagnoses, but…
remember patients are allowed more than one diagnosis
What is accommodative insufficiency?
difficulty stimulating accommodation, accommodative amplitude below lower limit expected for age
How are presbyopic patients different when it comes to accommodative amplitude?
amps may be low, indicating possible early presbyopia or latent hyperopia
What is one of the most common types of accommodative dysfunction?
accommodative insufficiency
What is ill-sustained accommodation?
sometimes considered a subclass of accommodative insufficiency, amplitude is normal but deteriorates over time and under stress
What is accommodative paralysis?
a true subclass of AI, completely stuck, associated with organic causes, very rare!
What are organic causes of accommodative paralysis?
increased ICP, tumor, degenerative disease, encephalitis, if new/sudden onset need imaging and referral
What is accommodative excess/spasm?
difficulty relaxing accommodation (overaccommodating for a given target), poor ability to perform testing with plus lenses, may have blurry distance vision after near work
What are other names for accommodative excess/spasm?
ciliary spasm, spasm of the near reflex, pseudomyopia
Is accommodative excess/spasm more or less symptomatic than some other anomalies?
more
What is accommodative infacility?
difficulty changing accommodative response level, both latency and speed of accommodative response are abnormal but amplitude is normal
T/F it is common for patients with accommodative dysfunction to show accommodative infacility
true
What are ICD-10 codes?
diagnostic codes, some diagnoses get grouped together
Which codes are considered refractive and medical won’t accept?
H52
What does the final digit mean in ICD-10 codes?
1=OD, 2=OS, 3=OU
