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Eye.ppt

  1. 1. EYE Ocular Disorders Olga González Rascón, M.D.
  2. 5. The Eye and its pathology <ul><li>Orbit </li></ul><ul><li>Eyelid </li></ul><ul><li>Conjunctiva </li></ul><ul><li>Sclera </li></ul><ul><li>Cornea </li></ul><ul><li>Anterior Segment </li></ul><ul><li>Uvea </li></ul><ul><li>Retina and Vitreous </li></ul><ul><li>Optic Nerve </li></ul>
  3. 6. ORBIT
  4. 7. Orbit <ul><li>Functional Anatomy and Proptosis </li></ul><ul><ul><li>The orbit is a compartment that is closed medially, laterally, and posteriorly. Any disease process that increases orbital contents results in the forward displacement of the eye, proptosis . </li></ul></ul><ul><ul><li>Proptosis may be axial (directly forward) or positional. </li></ul></ul><ul><ul><ul><li>Axial proptosis </li></ul></ul></ul><ul><ul><ul><ul><li>Glioma and meningioma </li></ul></ul></ul></ul><ul><ul><ul><li>Inferior and medial proptosis </li></ul></ul></ul><ul><ul><ul><ul><li>Sarcoid or neoplasm (lymphoma or epithelial neoplasm such as pleomorphic adenoma or adenoid cystic carcinoma ) </li></ul></ul></ul></ul>
  5. 8. Orbit <ul><li>Thyroid ophthalmopathy (Graves disease): </li></ul><ul><ul><li>Proptosis is caused by the accumulation of extracellular matrix proteins and variable degrees of fibrosis in the rectus muscles. </li></ul></ul>
  6. 9. Orbit <ul><li>Other Orbital Inflammatory Conditions </li></ul><ul><ul><li>Orbital cellulitis </li></ul></ul><ul><ul><ul><li>Caused by fungal infection ( Mucormycosis ) </li></ul></ul></ul><ul><ul><ul><li>Appears in systemic conditions such as Wegener granulomatosis </li></ul></ul></ul><ul><ul><li>Idiopathic orbital inflammation (orbital inflammatory pseudotumor) </li></ul></ul><ul><ul><ul><li>May be unilateral or bilateral </li></ul></ul></ul><ul><ul><ul><li>May be confined to the lacrimal gland ( sclerosing dacryoadenitis ) </li></ul></ul></ul><ul><ul><ul><li>Extraocular muscles ( orbital myositis ) </li></ul></ul></ul><ul><ul><ul><li>Tenon’s capsule ( posterior scleritis ) </li></ul></ul></ul><ul><ul><ul><li>In the long-term, patients may show evidence of systemic vasculitis or other forms of connective tissue diseases </li></ul></ul></ul>
  7. 10. Oribital cellulitis
  8. 11. Orbit <ul><li>Neoplasms </li></ul><ul><ul><li>Most frequent primary neoplasms are vascular in origin </li></ul></ul><ul><ul><ul><li>capillary hemangioma (infancy and early childhood) </li></ul></ul></ul><ul><ul><ul><li>lymphangioma </li></ul></ul></ul><ul><ul><ul><li>encapsulated cavernous hemangioma (adults) </li></ul></ul></ul><ul><ul><li>Only a handful of orbital masses are encapsulated </li></ul></ul><ul><ul><ul><li>pleomorphic adenoma </li></ul></ul></ul><ul><ul><ul><li>dermoid cyst </li></ul></ul></ul><ul><ul><ul><li>neurilemmoma </li></ul></ul></ul><ul><ul><li>Malignant lymphoma </li></ul></ul><ul><ul><li>Metastases: may produce characteristic periocular echymoses </li></ul></ul><ul><ul><ul><li>prostatic carcinoma </li></ul></ul></ul><ul><ul><ul><li>metastatic neuroblastoma </li></ul></ul></ul><ul><ul><ul><li>Wilms tumor </li></ul></ul></ul>
  9. 12. EYELID
  10. 13. Eyelid <ul><li>Functional anatomy </li></ul><ul><ul><li>The eyelid is a composite of skin externally and a mucosa (the conjunctiva) on the surface apposed to the eye </li></ul></ul>
  11. 14. Anatomy of the conjunctiva and the eyelids
  12. 15. Eyelid <ul><li>Functional Anatomy </li></ul><ul><ul><li>The eyelid covers and protects the eye, and generates critical components of the tear film </li></ul></ul><ul><ul><li>Eccrine and apocrine glands (glands of Moll) populate the eyelid. </li></ul></ul><ul><ul><li>Blepharitis: </li></ul></ul><ul><ul><ul><li>Obstruction of the drainage system of the sebaceous glands by chronic inflammation or by neoplasm </li></ul></ul></ul><ul><ul><ul><ul><li>Lipid extravasating into surrounding tissue and provoking a granulomatose response is called a lipogranuloma or chalazion </li></ul></ul></ul></ul>
  13. 16. Eyelid <ul><li>Neoplasms </li></ul><ul><ul><li>Basal cell carcinoma (most common malignancy of the eyelid) </li></ul></ul><ul><ul><ul><li>Has a distinct predilection for the lower eyelid and the medial canthus </li></ul></ul></ul><ul><ul><li>Sebaceous carcinoma </li></ul></ul><ul><ul><ul><li>May mimic chalazion or may diffusely thicken the eyelid </li></ul></ul></ul><ul><ul><ul><li>May also mimic inflammatory processes or ocular cicatricial pemphigoid </li></ul></ul></ul><ul><ul><ul><li>Tends to spread to the parotid and submandibular nodes </li></ul></ul></ul><ul><ul><ul><li>Mortality rate: 22 % </li></ul></ul></ul><ul><ul><li>AIDS- Kaposi sarcoma </li></ul></ul><ul><ul><ul><li>May develop in the eyelid or conjunctiva, typically thickenning the conjunctiva. </li></ul></ul></ul>
  14. 17. CONJUNCTIVA
  15. 18. Conjunctiva <ul><li>The conjunctiva -- the thin, transparent membrane that lines your eyeball and your eyelid -- can become inflamed for various reasons. </li></ul><ul><ul><li>Conjunctivitis </li></ul></ul><ul><ul><ul><li>Most cases of conjunctivitis run a predictable course, and the inflammation usually clears up in a few days. </li></ul></ul></ul><ul><ul><ul><li>Conjunctivitis is a common disease, especially in children. Although conjunctivitis can be highly contagious (known to spread rapidly in schools or daycare settings), it is rarely serious and will not damage your vision if detected and treated promptly. </li></ul></ul></ul>
  16. 21. Conjunctiva <ul><li>Functional Anatomy </li></ul><ul><ul><li>The conjunctiva is divided into topologic zones, each with distinctive histologic features and responses to disease: </li></ul></ul><ul><ul><ul><li>Palpebral conjunctiva </li></ul></ul></ul><ul><ul><ul><ul><li>The conjunctiva lining the interior of the eyelid ( palpebral conjunctiva ) folds in allergic conjunctivitis and bacterial infectious conjunctivitis </li></ul></ul></ul></ul><ul><ul><ul><li>Fornix </li></ul></ul></ul><ul><ul><ul><ul><li>In viral conjunctivitis, lymphoid follicles may enlarge sufficiently to be visualized clinically </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Granulomas </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Primary lymphoma </li></ul></ul></ul></ul><ul><ul><ul><li>Bulbar conjunctiva </li></ul></ul></ul>
  17. 22. Conjunctiva <ul><li>Conjunctival Scarring </li></ul><ul><ul><li>Caused by: </li></ul></ul><ul><ul><ul><li>Chlamydia trachomatis ( trachoma ) </li></ul></ul></ul><ul><ul><ul><li>Caustic alkalis </li></ul></ul></ul><ul><ul><ul><li>A sequela to ocular cicatricial pemphigoid </li></ul></ul></ul><ul><ul><ul><li>Iatrogenically through reaction to drugs or as a concequence of surgery </li></ul></ul></ul><ul><ul><li>Painful, dry eye </li></ul></ul>
  18. 23. Conjunctiva <ul><li>Pterygium and Pinguecula </li></ul><ul><ul><li>Appear as submucosal elevations on the conjunctiva </li></ul></ul><ul><ul><li>Result from actinic damage </li></ul></ul><ul><ul><li>Pterygium </li></ul></ul><ul><ul><ul><li>In the conjunctiva astride the limbus </li></ul></ul></ul><ul><ul><ul><li>Formed by fibrovascular connective tissue that migrates onto the cornea </li></ul></ul></ul><ul><ul><ul><li>May possibly induce mild astigmatism </li></ul></ul></ul><ul><ul><ul><li>Commonly excised </li></ul></ul></ul><ul><ul><ul><li>Occasionally precursors of actinic-induced neoplasms </li></ul></ul></ul><ul><ul><ul><ul><li>Squamous cell carcinoma </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Melanoma </li></ul></ul></ul></ul>
  19. 24. Conjunctiva <ul><li>Pterygium and Pinguecula </li></ul><ul><ul><li>Pinguecula </li></ul></ul><ul><ul><ul><li>Does not invade the cornea as pterygium does </li></ul></ul></ul><ul><ul><ul><li>Focal dehydration (dellen: a saucer-like depression in the corneal tissue) </li></ul></ul></ul><ul><ul><ul><li>Solar elastosis : sun-damaged collagen with elastic-like properties, that are the reason why the pinguecula is yellow in color </li></ul></ul></ul><ul><ul><ul><li>Actinic granuloma may develop secondary to a foreign body granulomatous reaction against the elastotic collagen </li></ul></ul></ul>
  20. 25. Conjunctiva <ul><li>Neoplasms </li></ul><ul><ul><li>Squamous neoplasms ( CIN – Conjunctival intraepithelial neoplasia ) </li></ul></ul><ul><ul><ul><li>May be associated with the presence of human papillomavirus types 16 and 18 </li></ul></ul></ul><ul><ul><li>Conjunctival nevi </li></ul></ul><ul><ul><li>Melanocytic neoplasms </li></ul></ul><ul><ul><ul><li>Tend to develop in the limbus </li></ul></ul></ul><ul><ul><ul><li>Spread first to the parotid or submandibular lymph nodes </li></ul></ul></ul><ul><ul><ul><li>Mortality rate: 25% </li></ul></ul></ul>
  21. 26. SCLERA
  22. 27. Sclera <ul><li>May appear “blue” in a variety of conditions: </li></ul><ul><ul><li>high intraocular pressure (staphyloma) </li></ul></ul><ul><ul><li>osteogenesis imperfecta </li></ul></ul><ul><ul><li>congenital melanosis oculi </li></ul></ul><ul><ul><ul><li>Heavily pigmented congenital nevus of the underlying uvea </li></ul></ul></ul><ul><ul><ul><li>Together with periocular cutaneous pigmentation </li></ul></ul></ul><ul><ul><ul><ul><li>Nevus of Ota </li></ul></ul></ul></ul>
  23. 28. CORNEA
  24. 29. Cornea <ul><li>Functional Anatomy </li></ul><ul><ul><li>The cornea and its overlying tear film – and not the lens – make up the major refractive surface of the eye </li></ul></ul><ul><ul><li>Corneal stroma lacks blood vessels and lymphatics (is very transparent; corneal transplantation is usually successful) </li></ul></ul><ul><ul><li>Scars can exist due to inflammation or trauma </li></ul></ul>
  25. 30. Normal corneal microarchitecture
  26. 31. Cornea <ul><li>Functional Anatomy </li></ul><ul><ul><li>Descemet membrane increases in thickness with age </li></ul></ul><ul><ul><ul><li>It is the site of copper deposition in the Kayser-Fleischer ring of Wilson disease </li></ul></ul></ul><ul><li>Keratitis and Ulcers </li></ul><ul><ul><li>Bacterial </li></ul></ul><ul><ul><li>Fungal </li></ul></ul><ul><ul><li>Viral (especially herpes simplex and herpes zoster) </li></ul></ul><ul><ul><ul><li>Chronic herpes simplex keratitis may be associated with a granulomatous reaction to Descemet’s membrane </li></ul></ul></ul><ul><ul><li>Protozoal (Acanthoamoeba) </li></ul></ul>
  27. 32. Congenital syphilis – interstitial keratitis, with blindness
  28. 33. ANTERIOR SEGMENT
  29. 34. Anterior Segment <ul><li>Functional Anatomy </li></ul><ul><ul><li>The eye can be divided conceptually and anatomically into two compartments : the anterior (which includes the cornea, anterior chamber, posterior chamber, iris, and lens) and the posterior pole (the remainder of the eye). </li></ul></ul>
  30. 36. Anterior Segment <ul><li>Functional Anatomy </li></ul><ul><ul><li>The anterior chamber is bounded anteriorly by the cornea, laterally by the trabecular meshwork, and posteriorly by the iris. Aqueous humor, formed by the pars plicata of the ciliary body, enters the posterior chamber, bathes the lens, and circulates through the pupil to gain access tot he anterior chamber. </li></ul></ul>
  31. 38. Anterior Segment <ul><li>Functional Anatomy </li></ul><ul><ul><li>The lens is a closed epithelial system; the basement membrane of the lens epitheliuim (known as the lens capsule) totally envelops the lens. </li></ul></ul><ul><ul><li>With aging, the size of the lens increases. </li></ul></ul><ul><ul><li>Neoplasms of the lens have not been described. </li></ul></ul>
  32. 39. Anterior Segment <ul><li>Cataract </li></ul><ul><ul><li>The term cataract describes lenticular opacities that may be congenital or acquired. </li></ul></ul><ul><ul><li>Causes: </li></ul></ul><ul><ul><ul><li>Systemic diseases: </li></ul></ul></ul><ul><ul><ul><ul><li>Galactosemia </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Diabetes mellitus </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Wilson disease </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Atopic dermatitis </li></ul></ul></ul></ul><ul><ul><ul><li>Drugs: </li></ul></ul></ul><ul><ul><ul><ul><li>Corticosteroids </li></ul></ul></ul></ul><ul><ul><ul><li>Radiation </li></ul></ul></ul><ul><ul><ul><li>Trauma </li></ul></ul></ul><ul><ul><ul><li>Many intraocular disorders </li></ul></ul></ul><ul><ul><ul><li>Age-related cataract ( nuclear sclerosis) </li></ul></ul></ul>
  33. 42. Rubella syndrome, or congenital rubella, is a group of physical abnormalities that have developed in an infant as a result of maternal infection and subsequent fetal infection with rubella virus. It is characterized by rash at birth, low birth weight, small head size, heart abnormalities, visual problems and bulging fontanelle.
  34. 43. Anterior Segment <ul><li>The Anterior Segment and Glaucoma </li></ul><ul><ul><li>The term glaucoma refers to a collection of diseases characterized by distinctive changes in the visual field and in the cup of the optic nerve. Most of the glaucomas area associated with elevated intraocular pressure, although some patients with normal intraocular pressure may develop characteristic optic nerve and visual field changes ( normal or low-tension glaucoma ). </li></ul></ul>
  35. 46. Anterior Segment <ul><li>The Anterior Segment and Glaucoma </li></ul><ul><ul><li>Glaucoma may be classified as: </li></ul></ul><ul><ul><ul><li>Open angle glaucoma </li></ul></ul></ul><ul><ul><ul><ul><li>Increased resistance to aqueous outflow in the open angle </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Primary </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Secondary </li></ul></ul></ul></ul><ul><ul><ul><li>Angle closure glaucoma </li></ul></ul></ul><ul><ul><ul><ul><li>The peripheral zone of the iris adheres to the trabecular meshwork and impedes the egress of aqueous from the eye. </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Primary </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Secondary </li></ul></ul></ul></ul>
  36. 47. Anterior Segment <ul><li>The Anterior Segment and Glaucoma </li></ul><ul><ul><li>Open angle glaucoma </li></ul></ul><ul><ul><ul><li>Primary </li></ul></ul></ul><ul><ul><ul><ul><li>The most common form of glaucoma </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Few changes are apparent </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Mutations in the GLC1A gene located on chromosome 1 </li></ul></ul></ul></ul><ul><ul><ul><li>Secondary </li></ul></ul></ul><ul><ul><ul><ul><li>Phacolysis (liquefied lens cortex, leaking through the lens capsule) </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Senescent red blood cells after trauma ( ghost cell glaucoma ) </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Anything that contributes to elevate the pressure on the surface of the eye in the presence of an open angle can contribute to other types of secondary open angle glaucoma </li></ul></ul></ul></ul>
  37. 48. Anterior Segment <ul><li>The Anterior Segment and Glaucoma </li></ul><ul><ul><li>Angle closure glaucoma </li></ul></ul><ul><ul><ul><li>Primary </li></ul></ul></ul><ul><ul><ul><ul><li>Typically develops in eyes with shallow anterior chambers </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Often found in patients with hyperopia (hypermetropia) </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Consequences: </li></ul></ul></ul></ul><ul><ul><ul><ul><ul><li>Pupillary block </li></ul></ul></ul></ul></ul><ul><ul><ul><ul><ul><li>Iris bomb é </li></ul></ul></ul></ul></ul><ul><ul><ul><ul><ul><li>Corneal edema </li></ul></ul></ul></ul></ul><ul><ul><ul><ul><ul><li>Bullous keratopathy </li></ul></ul></ul></ul></ul><ul><ul><ul><li>Secondary (causes) </li></ul></ul></ul><ul><ul><ul><ul><li>Contraction of various types of pathologic membranes that form over the surface of the iris </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Necrotic tumors </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Iridocorneal endothelial syndrome </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Following intraocular surgery or penetrating trauma </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Tumors in the ciliary body </li></ul></ul></ul></ul>
  38. 49. Anterior Segment <ul><li>Endophthalmitis and Panophthalmitis </li></ul><ul><ul><li>Causes: </li></ul></ul><ul><ul><ul><li>Blunt trauma </li></ul></ul></ul><ul><ul><ul><li>Corneal infections </li></ul></ul></ul><ul><ul><ul><li>Uveitis </li></ul></ul></ul><ul><ul><li>The term endophthalmitis is not applied clinically unless there is suppurative inflammation within the vitreous humor </li></ul></ul><ul><ul><li>Panophthalmitis: inflammation within the eye that involves the retina, choroid, and sclera and extends into the orbit </li></ul></ul><ul><ul><ul><li>Can produce proptosis </li></ul></ul></ul>
  39. 50. Exogenous panophthalmitis
  40. 51. UVEA
  41. 52. Uvea <ul><li>Together with the iris, choroid, and ciliary body constitute the uvea </li></ul><ul><li>The choroid is among the most richly vascularized sites in the body </li></ul><ul><li>As in the retina, there are no lymphatics within the uvea </li></ul>
  42. 53. The cherry-red spot in Tay-Sachs disease. A , Fundus photograph of the cherry-red spot in Tay-Sachs disease. B , Photomicrograph of the macula in a patient with Tay-Sachs disease, stained with periodic acid-Schiff to highlight the accumulation of ganglioside material in the retinal ganglion cells. The presence of ganglion cells filled with gangliosides outside the fovea blocks the transmission of the normal orange-red color of the choroid, but absence of ganglion cells within the fovea (to the right of the vertical bar) permits the normal orange-red color to be visualized, accounting for the so-called cherry-red spot.
  43. 54. Uvea <ul><li>Uveitis </li></ul><ul><ul><li>Causes: </li></ul></ul><ul><ul><ul><li>Infectious agents </li></ul></ul></ul><ul><ul><ul><ul><li>e.g.: pneumocystis carinii </li></ul></ul></ul></ul><ul><ul><ul><li>Idiopathic </li></ul></ul></ul><ul><ul><ul><ul><li>e.g.: sarcoidosis </li></ul></ul></ul></ul><ul><ul><ul><li>Autoimmune </li></ul></ul></ul><ul><ul><li>Sympathetic ophthalmia, an example of noninfectious uveitis </li></ul></ul><ul><ul><ul><li>Granulomatous inflammation typically affecting all components of the uvea </li></ul></ul></ul><ul><ul><ul><li>Treatment: administration of systemic immunosuppressive agents </li></ul></ul></ul>
  44. 55. Uvea <ul><li>Neoplasms </li></ul><ul><ul><li>Most common intraocular malignancy of adults: metastasis, typically to the choroid </li></ul></ul><ul><ul><ul><li>Suggestive of extremely short survival </li></ul></ul></ul><ul><ul><li>Nevi and Melanomas </li></ul></ul><ul><ul><ul><li>Uveal melanoma </li></ul></ul></ul><ul><ul><ul><ul><li>Most common primary intraocular malignancy of adults </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Most spread first to the liver; metastases appear many years after treatment. </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Mortality: 40% at ten years </li></ul></ul></ul></ul><ul><ul><ul><li>Uveal nevi </li></ul></ul></ul><ul><ul><ul><ul><li>Especially choroidal nevi, are common, affecting 10% of the Caucasian population. </li></ul></ul></ul></ul>
  45. 56. RETINA AND VITREOUS
  46. 58. Retina and Vitreous <ul><li>Functional Anatomy </li></ul><ul><ul><li>The retina responds to an injury by means of gliosis </li></ul></ul>
  47. 59. Retina and Vitreous <ul><li>The architecture of the retina explains the ophthalmoscopic appearance of a variety of ocular disorders. </li></ul><ul><li>Hemorrhages in the nerve fiber layer of the retina are oriented horizontally and appear ophthalmoscopically as streaks or “flames” </li></ul><ul><li>The external retinal layers are oriented perpendicular to the retinal surface, and hemorrhages in these outer layers appear as dots (cross sections of cylinders) </li></ul><ul><li>Exudates tend to accumulate in the outer plexiform layer of the retina, especially in the macula </li></ul>
  48. 61. Clinicopathologic correlations of retinal hemorrhages and exudates
  49. 62. Retina and Vitreous <ul><li>Retinal Detachment </li></ul><ul><ul><li>Separation of the neurosensory retina from the retinal pigment epithelium </li></ul></ul><ul><li>Retinal Vascular Disease </li></ul><ul><ul><li>Hypertension </li></ul></ul><ul><ul><ul><li>In retinal arteriolosclerosis, the thickened arteriolar wall changes the ophthalmic perception of circulating blood </li></ul></ul></ul><ul><ul><ul><ul><li>Vessels may appear narrowed, and the color of the blood column may change from bright red to copper and to silver depending on the degree of vascular wall thickness </li></ul></ul></ul></ul>
  50. 63. The retina in hypertension. A , The wall of the retinal arteriole (arrow) is thick. Note the exudate (e) in the retinal outer plexiform layer. B , The fundus in hypertension. The diameter of the arterioles is reduced, and the color of the blood column appears to be less saturated (copper wire-like). The retinal venule is compressed at a point where the artery and vein cross. If the wall of the vessel were thicker still, the degree of red color would diminish such that the vessels might appear clinically to have a &quot;silver-wire&quot; appearance. In this fundus photograph, note that the vein is compressed where the sclerotic arteriole crosses over it.
  51. 64. Retina and Vitreous <ul><li>Retinal Vascular Disease </li></ul><ul><ul><li>Hypertension </li></ul></ul><ul><ul><ul><li>Damage to choroidal vessels may produce focal choroidal infarcts, seen clinically as Elschnig’s spots . </li></ul></ul></ul><ul><ul><ul><li>The ophthalmoscopic finding of a macular star (a spokelike arrangement of exudate in the macula in malignant hypertension) results from exudate accumulating in the outer plexiform layer of the macula that is oriented obliquely rather than perpendicular to the retinal surface </li></ul></ul></ul>
  52. 65. Retina and Vitreous <ul><li>Retinal Vascular Disease </li></ul><ul><ul><li>Diabetes mellitus </li></ul></ul><ul><ul><ul><li>The retinal vasculopathy of diabetes mellitus may be classified into </li></ul></ul></ul><ul><ul><ul><ul><li>background (preproliferative) diabetic retinopathy </li></ul></ul></ul></ul><ul><ul><ul><ul><li>proliferative diabetic retinopathy </li></ul></ul></ul></ul>
  53. 66. The retina in diabetes mellitus
  54. 70. Retina and Vitreous <ul><li>Age-related Macular Degeneration (ARMD) </li></ul><ul><ul><li>The most common cause of irreversible visual morbidity in the United States </li></ul></ul><ul><ul><li>Etiology unclear </li></ul></ul><ul><li>Retinitis </li></ul><ul><ul><li>Candida (drug abuse or other causes) </li></ul></ul><ul><ul><li>Cytomegalovirus (AIDS) </li></ul></ul>
  55. 71. Retina and Vitreous <ul><li>Neoplasms </li></ul><ul><ul><li>Retinoblastoma </li></ul></ul><ul><ul><ul><li>The most common primary intraocular malignancy of children </li></ul></ul></ul><ul><ul><ul><li>In 40% of cases, retinoblastoma occurs in individuals who inherit a germ-line mutation of the RB allele. </li></ul></ul></ul><ul><ul><ul><li>May be bilateral, but also may be associated with pinealoblastoma (so-called “trilateral” retinoblastoma) </li></ul></ul></ul><ul><ul><li>Retinal Lymphoma </li></ul></ul>
  56. 77. OPTIC NERVE
  57. 78. Optic Nerve <ul><li>The pathology of the optic nerve is similar to the pathology of the brain. </li></ul><ul><li>Anterior Ischemic Optic Neuropathy (AION) </li></ul><ul><ul><li>Comprises a spectrum of injuries to the optic nerve varying from ischemia to infarction </li></ul></ul><ul><ul><li>Treatment: high doses of corticosteroids </li></ul></ul>
  58. 79. The optic nerve in anterior ischemic optic neuropathy (AION) and papilledema. A , In the relatively acute phases of AION, the optic nerve may be swollen, but it is relatively pale because of decreased perfusion.
  59. 80. Optic Nerve <ul><li>Papilledema </li></ul><ul><ul><li>Edema of the head of the optic nerve may develop as a consequence of compression of the nerve (as in a primary neoplasm of the optic nerve) or from elevations of cerebrospinal fluid pressure surrounding the nerve. </li></ul></ul><ul><ul><li>Swelling of the optic nerve head in elevated intracranial pressure is typically bilateral (unless the patient has experienced previous unilateral optic atrophy) and is commonly termed papilledema . </li></ul></ul>
  60. 81. In papilledema secondary to increased intracranial pressure, the optic nerve is typically swollen and hyperemic.
  61. 82. Normally, the termination of Bruch's membrane (arrowhead) is aligned with the beginning of the neurosensory retina, as indicated by the presence of stratified nuclei (arrow) , but in papilledema, the optic nerve is swollen, and the retina is displaced laterally. This is the histologic explanation for the blurred margins of the optic nerve head seen clinically in this condition
  62. 83. Optic Nerve <ul><li>Glaucomatous Optic Nerve Damage </li></ul>
  63. 84. Glaucomatous optic nerve cupping results, in part, from loss of retinal ganglion cells, the axons of which populate the optic nerve. C , The arrows point to the dura of the optic nerve. Notice the wide subdural space, a result of atrophy of the substance of the optic nerve. The degree of cupping on the surface of the nerve is striking in this eye, which was removed because of complications of long-standing glaucoma.
  64. 85. Credits <ul><li>Books: </li></ul><ul><ul><li>Robbins and Cortran, Pathologic Basis of Disease </li></ul></ul><ul><li>Images: </li></ul><ul><ul><li>RC-PBD, Elsevier </li></ul></ul><ul><ul><li>Various public internet sources </li></ul></ul><ul><ul><li>Department of Pathology library </li></ul></ul>

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