Blurring of Vision: A Practical Approach to Common Case Scenarios

Cataract

• Age related

• Congenital

• Trauma

• Ocular disease

• Systemic disease

• External agents

Systemic diseases

• Metabolic- DM, galactosemia,hypoparathyroidism

• Renal- Alport’s disease

• Cutaneous- atopic dermatitis

• Connective tissue- myotonic dystrophy, Marfan’s syndrome

• CNS- neurofibromatosis

• Down’s syndrome

Drug induced

• Steroids

• Lovastatin

• Ergot

• Chlorpromazine

• Psoralens

Symptoms

• Blur vision

• Glare

• Rapid change in spectacle prescription

• Decreased contrast

Treatment

• No medications or therapy can reverse cataract formation

• Only treatment

– Surgery to remove lens

– Replace lens with artificial lens implant (called intraocular lens or IOL)

Cataract surgery

• Remove the lens – Large incision

• Intracapsular extraction – Remove the lens/cataract in one piece

• Extracapsular extraction – Remove lens/cataract, but leave the capsule

behind

– Intraocular lens placed

Cataract surgery

• Changing trends in cataract surgery – Procedure

• Large incision small incision (phacoemulsification)

– Artificial lens • Rigid Foldable

– Anaesthesia • General Regional (injections) Topical (eyedrops

only)

Phacoemulsification

• Small incision <3mm • Make a small opening in

lens capsule • Use probe to break up

lens and suck lens out • Fold artificial lens and

insert through small wound into eye

• Incision seals itself and does not require suturing

Femtosecond cataract surgery

• Easier surgery

• Improved refractive outcomes

• Lower complication rates

• Shorter phacoemulsification time

• Expensive equipment

• Needs more space

• May not be suitable for all cases

Femtosecond cataract surgery

Dislocated lens

Dislocated lens

• Homocystinuria

• Marfan’s syndrome

• Weill- Marchesani’s syndrome

• Ehlers- Danlos’ syndrome

Homocystinuria

• AR disorder of methionine metabolism

• Mental retardation, growth retardation, osteoporosis, vascular events

• In 90% of patients, the lens is dislocated or subluxed, inferiorly or inferonasally

• May cause pupillary-block glaucoma, become trapped in the anterior chamber

Marfan’s syndrome

• AD with variable expressivity

• Skeletal, cardiovascular, ocular anomalies

• Zonular microfibrils are disrupted

• Bilateral, usually located upward and temporally

Weill- Marchesani’s syndrome

• Short stature, brachydactyly, joint stiffness

• Microspherophakia, ectopia of the lens, severe myopia, and glaucoma

• Pupillary-block glaucoma

Ehlers- Danlos’ syndrome

• Hyperextensibility of the skin, hypermobility of joints, tissue fragility

Symptoms

• Extreme hyperopic or myopic shifts, atypical astigmatism or acquired aphakia.

• Vision fluctuates dramatically as the patient alternates between phakic and aphakic vision

• Monocular diplopia, due to light entering the eye via two separate focal systems

Treatment

• Monocular diplopia - using opaque cosmetic contact lenses

• Pilocarpine therapy

• Lens dislocation into the anterior chamber causes pupillary block. In such cases, try to reposition the lens into the posterior chamber.

• Lens removal is really only indicated for patients with reduced vision or other visual or ocular symptoms.