Cataracts Flashcards
(7 cards)
Describe the pathophysiology of cataracts
Cataracts describe a progressively opaque eye lens, which reduces the light entering the eye and visual acuity.
The role of the lens is to focus light on the retina. It is held in place by suspensory ligaments attached to the ciliary body
The ciliary body contracts and relaxes to change the shape of the lens. When the ciliary body contracts, it releases tension on the suspensory ligaments, and the lens thickens. When the ciliary body relaxes, the suspensory ligaments tension, and the lens narrows. The lens has no blood supply and is nourished by the aqueous humour.
Risk factors for cataracts? [5]
- Increasing age
- Diabetes mellitus: Patients with diabetes are more likely to develop cataracts at a younger age due to non-enzymatic glycosylation of lens proteins.
- Steroid use: Long-term systemic or topical corticosteroid use is associated with posterior subcapsular cataract formation.
- Smoking and alcohol: Both have been linked with an increased risk of cataract development.
- Hypocalcaemia
Cataracts Ix? [2]
Ophthalmoscopy: done after pupil dilation. Findings: normal fundus and optic nerve
Slit-lamp examination. Findings: visible cataract
Mx for cataracts? [1]
Complications of cataracts can be categorised into intraoperative and postoperative.
Describe the intraoperative complications [2]
Capsular Tear:
- A common complication during phacoemulsification, potentially leading to vitreous loss or dislocation of lens fragments into the vitreous cavity.
Zonular Dehiscence:
- This may occur due to pre-existing weak zonules, especially in pseudoexfoliation syndrome or Marfan’s syndrome, leading to unstable lens and possible vitreous prolapse.
Complications of cataracts can be categorised into intraoperative and postoperative.
Describe the postoperative complications [2]
Posterior Capsule Opacification (PCO):
- The most frequent postoperative complication, occurring when lens epithelial cells proliferate and migrate onto the posterior capsule. YAG laser capsulotomy is often required for treatment.
Cystoid Macular Oedema (CMO):
- Characterised by fluid accumulation in the macula, it can cause reduced visual acuity postoperatively. It is usually treated with topical non-steroidal anti-inflammatory drugs (NSAIDs) or corticosteroids.
Endophthalmitis:
- A serious but rare complication marked by inflammation within the eye due to bacterial infection. Prompt diagnosis and treatment with intravitreal antibiotics are necessary to prevent permanent vision loss.
IOL Dislocation:
- The intraocular lens may dislocate either immediately after surgery or years later due to zonular weakness or capsular contraction syndrome. Surgical intervention is typically required for correction.
Tx of Endophthalmitis? [1]
Endophthalmitis describes inflammation of the inner contents of the eye, usually caused by infections, and is a rare but serious complication of cataract surgery. It can lead to vision loss. It is treated with intravitreal antibiotics injected directly into the eye.
