Pupilla learning lab
Bilateral Eye Examination Simulator
Compare combinations of right- and left-eye findings and bilateral responses on a virtual patient.
- Free in your browser
- English & Arabic
- Education & training
Your first practice session
- Establish the normal responses in both eyes.
- Choose right- and left-eye findings separately.
- Compare both responses and describe the asymmetry.
Common mistakes to avoid
- Assuming both eyes must have the same condition.
- Reporting only the illuminated eye.
For education and training only. Pupilla is not a medical device and must not be used for diagnosis or treatment decisions.
Understand the principles
Anisocoria: Horner syndrome, Adie tonic pupil and third nerve palsy
Anisocoria means the pupils are unequal in size. The key first step is to compare them in bright light and in dim light. If the difference is greater in the dark, the smaller pupil is abnormal because it cannot dilate — think Horner syndrome. If the difference is greater in bright light, the larger pupil is abnormal because it cannot constrict — think third nerve palsy, Adie tonic pupil or a pharmacologically dilated pupil. A difference of about 1 mm or less that is the same in light and dark is usually physiological.
RAPD and the swinging flashlight test
A relative afferent pupillary defect (RAPD), or Marcus Gunn pupil, means one eye sends a weaker light signal to the brainstem than the other. It is found with the swinging flashlight test: when the light swings from the healthy eye to the affected eye, both pupils dilate instead of staying small. An RAPD points to asymmetric optic nerve disease or extensive retinal damage, and on its own it does not make the pupils unequal in size.
Questions about this simulator
What can I practise with the Bilateral Eye Examination Simulator?
Compare combinations of right- and left-eye findings and bilateral responses on a virtual patient.
Do I need to install software or create an account?
Open the simulator free in a modern browser without installation. An account enables supported saved progress and results; coverage varies by module.
Can I use a phone or tablet?
You can access it in modern phone and tablet browsers. A larger screen gives diagrams and controls more space; performance depends on the device and browser.
Does this replace clinical training or patient diagnosis?
For education and training only. Pupilla is not a medical device and must not be used for diagnosis or treatment decisions.
References & further learning
Sources for the teaching principles. Listing a source does not imply its institution endorses or validates this simulator.