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In This Topic
Eye Disorders
Approach to the Ophthalmologic Patient
Ophthalmic Anatomy
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Topics in Approach to the Ophthalmologic Patient
  • Ophthalmic Anatomy
  • Evaluation of the Ophthalmologic Patient
       
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      Ophthalmic Anatomy

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      It is important to understand the anatomy of the eye prior to doing an examination. (See Fig. 1: Approach to the Ophthalmologic Patient: Cross-section of the eye.Figures for a cross-section of the eye.)

      Fig. 1

      Cross-section of the eye.

      The zonules of Zinn keep the lens suspended, and the muscles of the ciliary body focus the lens. The ciliary body also secretes aqueous humor, which fills the anterior and posterior chambers, passes through the pupil into the anterior chamber, and drains primarily via the Schlemm canal (see Fig. 1: Glaucoma: Aqueous humor production and flow.Figures). The iris regulates the amount of light entering the eye by adjusting the size of its central opening, the pupil. Visual images are focused on the retina. The conjunctiva covers the eyeball and lines the upper and lower eyelids; it ends at the limbus. The cornea is covered with epithelium that is more sensitive than and differs from the conjunctival epithelium.

      Last full review/revision March 2013 by Kathryn Colby, MD, PhD

      Content last modified April 2013

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