From GomerBlog's seminal work Physical Exam Tips: The Eye[1]:
An ophthalmologist will use special eye drops to help dilate the pupil. When the pupils are fully dilated at 10 cm, labor begins. Breech eye exams are tricky. Next, the ophthalmologist examines the retina for any signs of disease or placenta. Finally, the ophthalmologist patiently counts the number of rods and cones in each eye. Twice.
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