Embryologic origin of the ocular tissues. 1, Vitreous body; 2, ciliary muscle; 3, ciliary body epithelium; 4, zonular fibers; 5, corneal endothelium; 6, corneal stroma; 7, corneal epithelium; 8, iris sphincter; 9, iris dilator; 10, lens; 11, iris stroma; 12, trabecular meshw…

Comparison of sporadic retinoblastoma (A), where 2 independent mutations (“hits”) in the RB1 gene occur in a somatic cell, with hereditary retinoblastoma (B), where a germline mutation is present in every cell and second mutations can arise in multiple cells, leading to mult…

Vitreous. Gross photograph of the vitreous with the sclera, choroid, and retina removed from the eye of a 9-month-old child.

The uvea consists of the iris, ciliary body, and choroid. The classification of uveitis, established by the SUN (Standardization of Uveitis Nomenclature) Working Group, is based on the primary site of inflammation. Anterior uveitis (red) involves the iris and anterior ciliar…

A, Histologic section showing the 5 layers of the cornea (thickness given within parentheses): epithelium (40–50 micrometer), Bowman layer (8–15 micrometer), stroma (470–500 micrometer), Descemet membrane (10–12 micrometer), and endothelium (4–6 micrometer). B, Anterior se…

Rose bengal staining of herpetic dendritic keratitis.

Hyphema (blood in the anterior chamber).

Optical coherence tomography of a normal macula.

If the surgeon’s chair is too high, he or she must crouch to reach the oculars. This causes the shoulders to shrug, which tends to tighten the shoulder and arm muscles.

Surgical chair with adjustable armrests.

Age-related macular degeneration creates a hazy or dark area in central vision.

Bilateral tadpole pupils a rare phenomenon, in which the hallmark feature is that one segment of the iris is pulled to a peak.

Macula and retina immediately temporal to macula OD

Slit-lamp view of superior iris, anterior chamber, and limbus OD

Optic disc OD

External OD: Mild bulbar injection

Glaucomatous optic atrophy. Optic nerve cupping is increased vertically, with a cup–disc ratio of 0.8. Cupping is apparent at the point where the vessels disappear over the edge of the attenuated rim.

Cup–disc ratio. In this nondiseased optic disc, the cup is less than one-half the diameter of the disc, indicating absent or low level of suspicion of glaucoma.

Surgeon positioning at the 12:00 position. The pedals are positioned just to the side of the patient and table. At the 12:00 position, it is relatively easy for the surgeon to avoid inadvertent contact with the overlying table.

Careful and detailed ophthalmoscopic examination through dilated pupils is an important technique used to accurately grade diabetic retinopathy and to assess the need for laser photocoagulation surgery. Although most of the abnormalities are concentrated in the posterior ret…

Teller acuity cards.

Care must be taken to ensure proper placement of an eye pressure patch. First, place a folded eye patch over the patient’s closed eyelid. Then place a second, unfolded eye patch over the folded pad. Apply strips of tape firmly over the eye pads. Then pull the ends of the tap…

f the surgeon’s chair is too high, he or she must crouch to reach the oculars. This causes the shoulders to shrug, which tends to tighten the shoulder and arm muscles.

Flaring the left leg out and operating the foot pedal with the outside of the left foot drops the leg significantly and improves clearance under the bed.

Surgeon positioning while operating on a left eye at the temporal position. Here, the left leg is completely under the surgical bed.