75% off all plans

Ocular Pathology

On this page

General Ocular Pathology - Inflammatory Insights

  • Cardinal Signs: Rubor, tumor, calor, dolor, functio laesa.

  • Types:

    • Acute: PMNs, exudative (e.g., bacterial keratitis).
    • Chronic: Lymphocytes, macrophages, proliferative (e.g., chronic uveitis).
    • Granulomatous: Epithelioid cells, giant cells (e.g., sarcoid uveitis, TB).
      • Key cells: Langhans giant cells.
  • Mediators: Prostaglandins (PGs), leukotrienes, histamine, cytokines (TNF-α, ILs).

    • PGs: Miosis, pain, ↑ vascular permeability.
  • Cellular Players:

    • Neutrophils: Acute bacterial.
    • Lymphocytes/Plasma cells: Chronic, viral.
    • Eosinophils: Allergy, parasites.
    • Macrophages: Phagocytosis, chronic.
  • Sequelae: Synechiae, cataract, glaucoma, phthisis bulbi.

⭐ Sympathetic ophthalmia is a bilateral granulomatous panuveitis following penetrating ocular trauma to one eye.

Corneal & Lens Pathologies - Clarity Compromised

  • Corneal Clouding:
    • Keratitis (Inflammation):
      • Bacterial: Hypopyon, contact lens wear.
      • Viral: HSV (dendritic ulcer), HZO (pseudodendritic).
      • Fungal: Satellite lesions, feathery edges.
      • Acanthamoeba: Ring infiltrate, severe pain.
    • Dystrophies (Inherited, bilateral):
      • Fuchs: Endothelial decompensation, guttata.
      • Lattice: Amyloid deposits.
      • Granular: Hyaline deposits.
      • Macular: Mucopolysaccharide. 📌 AR, most severe.
    • Keratoconus: Conical protrusion, Fleischer ring, Munson's sign.
  • Lens Opacification (Cataract):
    • Types: Senile (Nuclear sclerosis, Cortical spokes, PSC), Congenital (e.g., Rubella), Traumatic (Rosette), Metabolic (Galactosemia - oil droplet).
    • Ectopia Lentis: Displaced lens (e.g., Marfan - superotemporal, Homocystinuria - inferonasal). Slit lamp view of mature senile cataract

⭐ Posterior Subcapsular Cataract (PSC) is common with chronic steroid use and causes early, significant glare.

Retinal & Uveal Pathologies - Vision Vanquishers

  • Retinal Vascular Diseases:
    • Diabetic Retinopathy (DR):
      • NPDR: Microaneurysms, hemorrhages, exudates, Cotton Wool Spots (CWS).
      • PDR: Neovascularization (NVD/NVE), vitreous hemorrhage, tractional RD.
    • Hypertensive Retinopathy: Arteriolar narrowing, AV nipping, CWS, flame hemorrhages, macular star, papilledema (Grade IV).
    • Retinal Vein Occlusion (RVO):
      • CRVO: "Blood & thunder" fundus, sudden painless vision loss.
      • BRVO: Sectoral hemorrhages.
    • Retinal Artery Occlusion (RAO):
      • CRAO: Sudden, profound, painless vision loss; "cherry-red spot". Ocular emergency!
  • Retinal Degenerations:
    • Age-related Macular Degeneration (AMD):
      • Dry (Atrophic): Drusen, RPE atrophy. Gradual vision loss.
      • Wet (Exudative): Choroidal neovascularization (CNVM), leakage. Rapid, severe vision loss.
*   Retinitis Pigmentosa (RP): Progressive nyctalopia, peripheral field loss, "bone spicule" pigmentation. 📌 Mnemonic: RP = Rods Perish.
  • Ocular Tumors:
    • Uveal Melanoma: Most common primary intraocular tumor in adults. Liver metastasis common.
    • Retinoblastoma: Most common in children. Leukocoria, strabismus.

      ⭐ Retinoblastoma: Associated with Rb1 gene mutation. Histopathology shows Flexner-Wintersteiner rosettes. Fundus with cherry-red spot and attenuated arteries

Glaucoma & Optic Neuropathies - Pressure Problems

  • Glaucoma: Optic neuropathy; characteristic disc cupping & visual field (VF) loss. Often associated with ↑ Intraocular Pressure (IOP).
    • Primary Open-Angle Glaucoma (POAG): Most common, chronic, painless. Due to trabecular meshwork dysfunction.
    • Angle-Closure Glaucoma (ACG): Iris obstructs trabecular meshwork. Acute (painful, red eye, halos, nausea) or chronic.
  • Pathophysiology: ↑IOP → mechanical stress/vascular compromise at optic nerve head → Retinal Ganglion Cell (RGC) death → optic disc cupping (Cup-to-Disc Ratio > 0.5), characteristic VF defects.
  • Risk Factors: Age, family history, ethnicity (African/Hispanic for POAG, Asian for ACG), myopia (POAG), hypermetropia (ACG), diabetes, prolonged steroid use.
  • Diagnosis: Tonometry (IOP measurement), gonioscopy (angle assessment), optic disc exam, perimetry (VF testing).

    ⭐ Normal IOP is 10-21 mmHg. In acute angle closure glaucoma, IOP can rapidly rise, often exceeding 50 mmHg.

  • Other Optic Neuropathies:
    • Ischemic Optic Neuropathy (ION): Arteritic (AION - e.g., Giant Cell Arteritis, ESR↑, urgent steroids) & Non-Arteritic (NAION - common, vasculopathic risks like DM, HTN).
    • Optic Neuritis: Inflammation, often Multiple Sclerosis-associated; pain on eye movement, ↓vision, Relative Afferent Pupillary Defect (RAPD).
    • Compressive/Infiltrative: Tumors, thyroid eye disease.

Glaucoma: Optic disc cupping and visual field loss

High‑Yield Points - ⚡ Biggest Takeaways

  • Basal cell carcinoma: most common malignant eyelid tumor; locally invasive, rarely metastasizes.
  • Retinoblastoma: RB1 gene; most common childhood intraocular malignancy; leukocoria, Flexner-Wintersteiner rosettes.
  • Uveal melanoma: most common adult primary intraocular malignancy; liver metastasis is frequent.
  • Chalazion: chronic lipogranulomatous inflammation of a Meibomian gland (blocked duct).
  • Pterygium: elastotic degeneration of collagen, fibrovascular growth from conjunctiva, linked to UV exposure.
  • Diabetic retinopathy: microaneurysms (earliest sign); neovascularization (proliferative DR).

Continue reading on OnCourse

Sign up for free to access the full lesson, plus unlimited questions, flashcards, AI-powered notes, and more.

CONTINUE READING — FREE

or get the app

Rezzy AI Tutor

Have doubts about this lesson?

Ask Rezzy, our AI tutor, to explain anything you didn't understand

Practice Questions: Ocular Pathology

Test your understanding with these related questions

A 45-year-old diabetic presents with sudden painless vision loss. Cotton wool spots and dot hemorrhages seen. HbA1c is 9.2. Most likely diagnosis?

1 of 5

Flashcards: Ocular Pathology

1/10

Tight junctions between _____ form the inner blood retinal barrier

TAP TO REVEAL ANSWER

Tight junctions between _____ form the inner blood retinal barrier

endothelial cells of retinal capillaries

browseSpaceflip

Enjoying this lesson?

Get full access to all lessons, practice questions, and more.

START FOR FREE
Rezzy AI Tutor