Ophthalmology for AMC MCQ

A 74 year old man has two years of gradually worsening, painless blurring of vision in both eyes, with glare from oncoming headlights making night driving difficult and colours looking faded. His visual acuity is reduced, the red reflex is dim, and slit-lamp examination shows lens opacities. The rest of the eye, including the macula, looks normal. What is the most likely diagnosis?

1. Refractive error Blurring corrected by lenses. Gradual painless blurring with glare and lens opacities and a normal fundus makes it worth considering.
2. Retinoblastoma A white pupil in a child that must be excluded. Gradual painless blurring with glare and lens opacities and a normal fundus makes it a serious consideration.
3. Congenital cataract A white pupil or absent red reflex in a child. Gradual painless blurring with glare and lens opacities and a normal fundus makes it urgent.
4. Diabetic retinopathy Visual loss with retinal changes in diabetes. Gradual painless blurring with glare and lens opacities and a normal fundus raises it.
5. Cataracts correct Correct. Gradual painless blurring with glare and lens opacities on slit-lamp with a normal fundus is age-related cataract.

The point: A cataract is a clouding of the lens, and it is the commonest cause of reversible blindness worldwide. It develops gradually, usually with age, and causes a painless, progressive blurring of vision, glare and haloes around lights that trouble driving at night, faded colour vision and a gradual dimming, and sometimes a change in the spectacle prescription as the lens changes. Examination shows reduced visual acuity and a loss of the red reflex, with the opacity visible on slit-lamp examination. Risk factors beyond age include diabetes, corticosteroid use, smoking, high sun exposure and previous eye injury or surgery, and in children a congenital cataract must be detected early because it threatens visual development and shows as a white pupil or an absent red reflex. The diagnosis is clinical. There is no effective drug treatment; management is surgical, with day-case phacoemulsification and insertion of an intraocular lens, offered when the cataract affects the person's function or vision enough to warrant it, or urgently in a child. The operation is highly effective, and the main serious complication to counsel about is endophthalmitis, a rare but sight-threatening post-operative infection presenting with a painful red eye and falling vision.

Source: Therapeutic Guidelines (Australia) — Eye: cataract Therapeutic Guidelines (Australia) · tier 3, national formulary

A 74 year old man has two years of gradually worsening, painless blurring of vision in both eyes, with glare from oncoming headlights making night driving difficult and colours looking faded. His visual acuity is reduced, the red reflex is dim, and slit-lamp examination shows lens opacities. The rest of the eye, including the macula, looks normal. What is the most appropriate initial investigation?

1. Slit-lamp examination of the lens correct Correct. Slit-lamp examination showing the lens opacity confirms the cataract.
2. Fundus examination where possible To exclude other causes. Gradual painless blurring with glare and lens opacities and a normal fundus makes it necessary.
3. Red reflex screening in a child For congenital cataract. Gradual painless blurring with glare and lens opacities and a normal fundus makes it important.
4. Assessment of functional impact Guides surgery. Gradual painless blurring with glare and lens opacities and a normal fundus makes it useful.
5. Visual acuity assessment Reduced by the cataract. Gradual painless blurring with glare and lens opacities and a normal fundus makes it central.

The point: A cataract is a clouding of the lens, and it is the commonest cause of reversible blindness worldwide. It develops gradually, usually with age, and causes a painless, progressive blurring of vision, glare and haloes around lights that trouble driving at night, faded colour vision and a gradual dimming, and sometimes a change in the spectacle prescription as the lens changes. Examination shows reduced visual acuity and a loss of the red reflex, with the opacity visible on slit-lamp examination. Risk factors beyond age include diabetes, corticosteroid use, smoking, high sun exposure and previous eye injury or surgery, and in children a congenital cataract must be detected early because it threatens visual development and shows as a white pupil or an absent red reflex. The diagnosis is clinical. There is no effective drug treatment; management is surgical, with day-case phacoemulsification and insertion of an intraocular lens, offered when the cataract affects the person's function or vision enough to warrant it, or urgently in a child. The operation is highly effective, and the main serious complication to counsel about is endophthalmitis, a rare but sight-threatening post-operative infection presenting with a painful red eye and falling vision.

Source: Therapeutic Guidelines (Australia) — Eye: cataract Therapeutic Guidelines (Australia) · tier 3, national formulary

A 74 year old man has two years of gradually worsening, painless blurring of vision in both eyes, with glare from oncoming headlights making night driving difficult and colours looking faded. His visual acuity is reduced, the red reflex is dim, and slit-lamp examination shows lens opacities. The rest of the eye, including the macula, looks normal. What is the most appropriate next step in management?

1. Counsel about endophthalmitis warning signs A painful red eye with falling vision. Gradual painless blurring with glare and lens opacities and a normal fundus makes it a safety step.
2. Cataract surgery with an intraocular lens correct Correct. Cataract is treated definitively with surgery and an intraocular lens.
3. Urgent referral for a child with a cataract To protect visual development. Gradual painless blurring with glare and lens opacities and a normal fundus makes it the priority.
4. Ophthalmology referral For assessment and surgery. Gradual painless blurring with glare and lens opacities and a normal fundus makes it thorough.
5. Address modifiable risk factors Smoking and glucose control. Gradual painless blurring with glare and lens opacities and a normal fundus makes it preventive.

The point: A cataract is a clouding of the lens, and it is the commonest cause of reversible blindness worldwide. It develops gradually, usually with age, and causes a painless, progressive blurring of vision, glare and haloes around lights that trouble driving at night, faded colour vision and a gradual dimming, and sometimes a change in the spectacle prescription as the lens changes. Examination shows reduced visual acuity and a loss of the red reflex, with the opacity visible on slit-lamp examination. Risk factors beyond age include diabetes, corticosteroid use, smoking, high sun exposure and previous eye injury or surgery, and in children a congenital cataract must be detected early because it threatens visual development and shows as a white pupil or an absent red reflex. The diagnosis is clinical. There is no effective drug treatment; management is surgical, with day-case phacoemulsification and insertion of an intraocular lens, offered when the cataract affects the person's function or vision enough to warrant it, or urgently in a child. The operation is highly effective, and the main serious complication to counsel about is endophthalmitis, a rare but sight-threatening post-operative infection presenting with a painful red eye and falling vision.

Source: Therapeutic Guidelines (Australia) — Eye: cataract Therapeutic Guidelines (Australia) · tier 3, national formulary