COT Ocular Disease Recognition and Pathology — Questions and Answers
Question 1: A patient presents with sudden onset of severe eye pain, nausea, blurred vision, and halos around lights. Examination reveals a steamy cornea and a mid-dilated, non-reactive pupil. These findings are MOST consistent with:
- Primary open-angle glaucoma
- Acute angle-closure glaucoma (Correct answer)
- Anterior uveitis
- Corneal abrasion
Correct answer: Acute angle-closure glaucoma
Acute angle-closure glaucoma presents with sudden severe eye pain, nausea/vomiting, corneal edema (steamy appearance), and a mid-dilated non-reactive pupil due to markedly elevated intraocular pressure. This is an ocular emergency requiring immediate treatment.
Question 2: Drusen deposits located beneath the retinal pigment epithelium (RPE) are a hallmark finding of:
- Diabetic retinopathy
- Retinitis pigmentosa
- Age-related macular degeneration (AMD) (Correct answer)
- Central serous chorioretinopathy
Correct answer: Age-related macular degeneration (AMD)
Drusen are extracellular deposits beneath the RPE that are the earliest clinical sign of age-related macular degeneration. Small hard drusen have low risk of progression, while large soft drusen are associated with higher risk of progression to advanced AMD.
Question 3: A patient describes a 'curtain coming across' their peripheral vision with associated flashing lights. These symptoms are MOST suggestive of:
- Central serous retinopathy
- Optic neuritis
- Retinal detachment (Correct answer)
- Vitreous hemorrhage
Correct answer: Retinal detachment
A 'curtain' or 'shadow' moving across the visual field combined with photopsia (flashing lights) is classic for rhegmatogenous retinal detachment. The flashes result from vitreoretinal traction, and the curtain represents the area of detached retina. This is an ocular emergency.
Question 4: Cotton-wool spots seen on fundus examination are caused by:
- Cholesterol emboli blocking retinal arterioles
- Ischemic infarction of the nerve fiber layer causing axoplasmic stasis (Correct answer)
- Drusen deposits in the nerve fiber layer
- Subretinal fluid accumulation
Correct answer: Ischemic infarction of the nerve fiber layer causing axoplasmic stasis
Cotton-wool spots represent focal ischemic infarctions of the retinal nerve fiber layer that cause axoplasmic stasis. They appear white and fluffy on fundus exam and are commonly seen in diabetic retinopathy, hypertensive retinopathy, and HIV retinopathy.
Question 5: A pterygium is BEST described as:
- A yellow, raised, non-vascular lesion on the bulbar conjunctiva that does not cross the limbus
- A fibrovascular growth of conjunctival tissue that invades and grows across the cornea (Correct answer)
- A benign, fluid-filled cyst on the palpebral conjunctiva
- An inflammatory condition causing follicular hypertrophy of the tarsal conjunctiva
Correct answer: A fibrovascular growth of conjunctival tissue that invades and grows across the cornea
A pterygium is a fibrovascular proliferation of conjunctival tissue that extends from the bulbar conjunctiva across the limbus onto the corneal surface. It differs from a pinguecula, which is a similar yellow deposit that does not cross the limbus. UV exposure is the primary risk factor.
Question 6: In diabetic patients, which type of diabetic retinopathy is characterized by the growth of abnormal new blood vessels on the retinal surface or optic disc?
- Background (non-proliferative) diabetic retinopathy
- Clinically significant macular edema
- Proliferative diabetic retinopathy (Correct answer)
- Preproliferative diabetic retinopathy
Correct answer: Proliferative diabetic retinopathy
Proliferative diabetic retinopathy (PDR) is defined by neovascularization — abnormal new blood vessels growing on the retinal surface, optic disc, or into the vitreous. These fragile vessels can bleed, causing vitreous hemorrhage, or lead to tractional retinal detachment. PDR represents advanced, sight-threatening disease.
COT Ocular Disease Recognition and Pathology
A patient presents with sudden onset of severe eye pain, nausea, blurred vision, and halos around lights.
Examination reveals a steamy cornea and a mid-dilated, non-reactive pupil.
These findings are MOST consistent with: