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  1. <Health Topics
    Eye Disorders
    Biology of the Eyes
    • Structure and Function of the Eyes
    • Muscles, Nerves, and Blood Vessels of the Eyes
    • Protective Features of the Eyes
    • Effects of Aging on the Eyes
    Symptoms of Eye Disorders
    • Sudden Vision Loss
      • Causes
        • Common causes
        • Less common causes
      • Evaluation
        • When to see a doctor
        • What the doctor does
        • Testing
      • Treatment
      • Key Points
    • Eye Pain
      • Causes
        • Common causes
      • Evaluation
        • Warning signs
        • When to see a doctor
        • What the doctor does
        • Testing
      • Treatment
      • Key Points
    • Eyelid Swelling
      • Causes
        • Common causes
        • Less common causes
      • Evaluation
        • Warning signs
        • When to see a doctor
        • What the doctor does
        • Testing
      • Treatment
      • Key Points
    • Eye Flashes and Floaters
      • Causes
      • Evaluation
      • Warning signs
      • When to see a doctor
      • What the doctor does
      • Testing
      • Treatment
      • Key Points
    • Eye Redness
      • Causes
      • Evaluation
        • Warning signs
        • When to see a doctor
        • What the doctor does
        • Testing
      • Treatment
      • Key Points
    • Bulging Eyes
      • Causes
      • Evaluation
        • Warning signs
        • When to see a doctor
        • What the doctor does
        • Testing
      • Treatment
      • Key Points
    • Watery Eyes
      • Causes
      • Evaluation
        • Warning signs
        • When to see a doctor
        • What the doctor does
        • Testing
      • Treatment
      • Essentials for Older People
      • Key Points
    • Unequal Pupils
      • Causes
      • Evaluation
        • Warning signs
        • When to see a doctor
        • What the doctor does
        • Testing
      • Treatment
      • Key Points
    • Blurred Vision
      • Causes
        • Common causes
        • Less common causes
      • Evaluation
        • Warning signs
        • When to see a doctor
        • What the doctor does
        • Testing
      • Treatment
      • Essentials for Older Adults
      • Key Points
    • Double Vision
      • Causes
      • Evaluation
        • Warning signs
        • When to see a doctor
        • What the doctor does
        • Testing
      • Treatment
      • Key Points
    • Other Eye Symptoms
      • Impaired Depth Perception
      • Glare and Halos
      • Night Blindness
      • Color Blindness
      • Light Sensitivity
      • Itchy Eyes
      • Dry Eyes
      • Changes in the Appearance of the Eyes
    Diagnosis of Eye Disorders
    • Tests for Eye Disorders
      • Angiography
      • Electroretinography
      • Ultrasound
      • Pachymetry
      • Optical Coherence Tomography
      • Computed Tomography (CT) and Magnetic Resonance Imaging (MRI)
    • The Eye Examination
      • Refraction
      • Visual Field Testing
      • Color Vision Testing
      • Ophthalmoscopy
      • Slit-Lamp Examination
      • Tonometry
    Cataract
    • Cataract
      • Symptoms
      • Diagnosis
      • Treatment
        • Surgery
        • Recovery
        • Complications
      • Prevention
    Conjunctival and Scleral Disorders
    • Ocular Mucous Membrane Pemphigoid
      • Symptoms
      • Diagnosis
      • Treatment
    • Subconjunctival Hemorrhage
    • Overview of Conjunctival and Scleral Disorders
    • Infectious Conjunctivitis
      • Causes
        • Viruses
        • Bacteria
        • Other causes
      • Symptoms
      • Diagnosis
      • Treatment
        • Conjunctivitis caused by bacteria
        • Conjunctivitis caused by viruses
      • Prognosis
    • Trachoma
      • Symptoms
      • Diagnosis
      • Treatment
      • Prevention
    • Allergic Conjunctivitis
      • Symptoms
      • Diagnosis
      • Treatment
    • Episcleritis
      • Treatment
    • Scleritis
      • Symptoms
      • Diagnosis
      • Treatment
      • Prognosis
    • Pinguecula and Pterygium
      • Pinguecula
      • Pterygium
    Corneal Disorders
    • Bullous Keratopathy
      • Symptoms
      • Diagnosis
      • Treatment
    • Corneal Transplantation
      • Corneal Transplantation Procedures
      • Complications of Corneal Transplantation
      • Corneal Limbal Stem Cell Transplantation
    • Herpes Simplex Keratitis
      • Symptoms
      • Diagnosis
      • Treatment
    • Herpes Zoster Ophthalmicus
      • Symptoms
      • Diagnosis
      • Treatment
      • Prevention
    • Keratoconus
      • Treatment
    • Phlyctenular Keratoconjunctivitis
      • Symptoms
      • Diagnosis
      • Treatment
    • Superficial Punctate Keratitis
      • Symptoms
      • Diagnosis
      • Treatment
    • Cogan Syndrome
      • Symptoms
      • Diagnosis
      • Treatment
    • Interstitial Keratitis
      • Symptoms
      • Diagnosis
      • Treatment
    • Introduction to Corneal Disorders
    • Corneal Ulcer
      • Causes
      • Symptoms
        • Complications of corneal ulcer
      • Diagnosis
      • Treatment
    • Keratoconjunctivitis Sicca
      • Causes
      • Symptoms
      • Diagnosis
      • Treatment
    • Keratomalacia
      • Symptoms
      • Diagnosis
      • Treatment
    • Peripheral Ulcerative Keratitis
      • Symptoms
      • Diagnosis
      • Treatment
      • Prognosis
    Eyelid and Tearing Disorders
    • Blepharospasm
    • Overview of the Eyelids and Tears
    • Blepharitis
      • Causes
      • Symptoms
      • Diagnosis
      • Treatment
    • Canaliculitis
      • Diagnosis
      • Treatment
    • Chalazion and Stye (Hordeolum)
      • Symptoms
        • Chalazion
        • Stye (hordeolum)
      • Diagnosis
      • Treatment
        • Chalazion
        • Stye (hordeolum)
    • Dacryocystitis
      • Symptoms
      • Diagnosis
      • Treatment
    • Dacryostenosis
      • Congenital dacryostenosis
      • Acquired dacryostenosis
    • Entropion and Ectropion
      • Symptoms
      • Diagnosis
      • Treatment
    • Eyelid Growths
      • Xanthelasma
      • Basal cell carcinoma of the eye
      • Other cancerous growths of the eyelids
    • Trichiasis
      • Symptoms
      • Diagnosis
      • Treatment
    Eye Socket Disorders
    • Orbital Cellulitis
      • Symptoms
      • Diagnosis
      • Treatment
    • Preseptal Cellulitis
      • Symptoms
      • Diagnosis
      • Treatment
    • Cavernous Sinus Thrombosis
      • Causes
      • Symptoms
      • Diagnosis
      • Treatment
      • Prognosis
    • Introduction to Eye Socket Disorders
    • Inflammation of the Orbit
      • Causes
      • Symptoms
      • Diagnosis
      • Treatment
    • Tumors of the Orbit
    Glaucoma
    • Glaucoma
      • Types of glaucoma
      • Symptoms
        • Open-angle glaucoma
        • Closed-angle glaucoma
      • Diagnosis
        • Screening
      • Treatment
        • Medications
        • Surgery
        • Secondary glaucoma
      • More Information
    Optic Nerve Disorders
    • Nutritional and Toxic Optic Neuropathies
      • Causes
      • Symptoms
      • Diagnosis
      • Treatment
      • Prognosis
    • Compressive Optic Neuropathy
      • Causes
      • Symptoms
      • Diagnosis
      • Treatment
    • Hereditary Optic Nerve Disorders
      • Causes
      • Symptoms
      • Diagnosis
      • Treatment
    • Overview of Optic Nerve Disorders
    • Papilledema
      • Causes
      • Symptoms
      • Diagnosis
      • Treatment
    • Optic Neuritis
      • Causes
      • Symptoms
      • Diagnosis
      • Treatment
    • Ischemic Optic Neuropathy
      • Causes
      • Symptoms
      • Diagnosis
      • Treatment
      • Prognosis
    Refractive Disorders
    • Overview of Refractive Disorders
      • Causes
      • Symptoms
      • Diagnosis
      • Treatment
    • Corrective Lenses
      • Eyeglasses
      • Contact Lenses
        • Rigid contact lenses
        • Scleral contact lenses
        • Soft contact lenses
        • Care and complications of contact lenses
    • Surgery for Refractive Errors
      • Types of refractive surgery
      • Laser In Situ Keratomileusis (LASIK)
      • Photorefractive Keratectomy (PRK)
      • Other Refractive Surgery
        • Kerato-lenticule extraction (KLEx)
        • Phakic intraocular lenses (Phakic IOLs)
        • Clear lensectomy (refractive lens exchange)
        • Radial keratotomy and astigmatic keratotomy
    Retinal Disorders
    • Overview of Retinal Disorders
    • Age-Related Macular Degeneration (AMD or ARMD)
      • Causes
        • Types
      • Symptoms
        • Dry AMD
        • Wet AMD
      • Diagnosis
      • Treatment
        • Dietary supplements
        • Medications and laser procedures
        • Adjusting to vision loss
      • More Information
    • Epiretinal Membrane
      • Symptoms
      • Diagnosis
      • Treatment
      • More Information
    • Detachment of the Retina
      • Symptoms
      • Diagnosis
      • Treatment
      • Prognosis
      • More Information
    • Retinitis Pigmentosa
      • Symptoms
      • Diagnosis
      • Treatment
      • More Information
    • Blockage of Central Retinal Veins and Branch Retinal Veins
      • Symptoms
      • Diagnosis
      • Treatment
      • Prognosis
      • More Information
    • Hypertensive Retinopathy
      • Diagnosis
      • Treatment
      • More Information
    • Diabetic Retinopathy
      • Symptoms
        • Nonproliferative diabetic retinopathy
        • Proliferative diabetic retinopathy
      • Diagnosis
      • Treatment
      • Prevention
      • More Information
    • Cancers Affecting the Retina
      • Choroidal melanoma
        • Symptoms
        • Diagnosis
        • Treatment
      • Choroidal metastases
        • Symptoms
        • Diagnosis
        • Treatment
        • More Information
    • Blockage of Central Retinal Arteries and Branch Retinal Arteries
      • Symptoms
      • Diagnosis
      • Treatment
      • Prognosis
      • More Information
    Uveitis and Related Disorders
    • Endophthalmitis
      • Symptoms
      • Diagnosis
      • Treatment
      • Prognosis
    • Sympathetic Ophthalmia
      • Causes
      • Symptoms
      • Diagnosis
      • Treatment
    • Uveitis
      • Causes
      • Symptoms
      • Diagnosis
      • Treatment
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