Contact Lenses
121 lenses
Quickly search and sort lenses by brand, replacement, oxygen permeability (Dk), and more.
All 121 lenses →Contact LensesMedicationsGlossarySchoolsHandoutsCalculators
121 lenses
Quickly search and sort lenses by brand, replacement, oxygen permeability (Dk), and more.
All 121 lenses →237 medications
All the information you need to confidently prescribe drops and drugs for ocular disease treatment.
All 237 medications →238 terms
From aberrant regeneration to zylonite, find concise definitions of ophthalmic terms and optical concepts.
All 238 terms →Congenital strabismus is the older name for infantile esotropia syndrome, the most common cause of a constant strabismus that begins before 1 year of age. The old name is misleading, because the deviation is not usually present at birth.1 Infantile esotropia is defined as a manifest esodeviation with onset between birth and 6 months of age, and the term is preferred over the older congenital esotropia.2
5 calculators
Each calculator has its own page you can bookmark. Every result shows its work.
All 5 calculators →Try it · Back vertex power
More calculatorsToric over-refractionDiopters ↔ radiusTranspositionHydroxychloroquine
9 PDFs
Everything from Amsler grids for your patients to clinical guides and tables to use in your practice.
All handouts →A guide for opticians: which tint or filter to offer for night driving, glare, sports, screens and light sensitivity, why it works, and what to say, with FL-41, Avulux and 41 linked sources.
1,816 questions
Timed practice exams with worked explanations and a score breakdown by topic. The first half of Exam 1 is free.
Open exam prep →EyeKnow O.D. Pro adds 3 more full-length exams and custom drills from all 1,816 questions. $179 for 12 months, intro price to March 18, 2027. See Pro plans →
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*EyeKnow O.D. is an independent study tool. It is not affiliated with, endorsed by, or sponsored by the National Board of Examiners in Optometry (NBEO®). “NBEO” is used here only to indicate exam coverage.
27 programs
Admissions, cost, board pass rates and campus life for every accredited OD program, side by side.
Compare all 27 →Pikeville, KY · Small town · Private