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Describe complicated cataract with its causes and management.

Ophthalmology · 3rd Professional

Complicated cataract (cataracta complicata) is opacification of the lens secondary to some other intraocular disease, which disturbs the nutrition or metabolism of the lens.
It is therefore a sign of another disorder, and the underlying disease determines both the management and the visual prognosis.

Group	Causes
Inflammatory	Chronic anterior uveitis — much the commonest cause, and particularly the uveitis of juvenile idiopathic arthritis and FUCHS heterochromic iridocyclitis; and pars planitis
Degenerative	Retinitis pigmentosa, in which posterior subcapsular cataract is characteristic; high myopia; and retinal detachment
Glaucoma	Acute angle closure produces glaukomflecken — small grey-white anterior subcapsular opacities of necrotic lens epithelium.
Intraocular tumour	By local effect and by inflammation
Post-surgical	Particularly after vitrectomy, where nuclear sclerosis is almost universal within a few years, and after silicone oil tamponade

The characteristic morphology is a posterior subcapsular cataract, often with a "polychromatic lustre" or "breadcrumb" appearance of iridescent, multicoloured granules at the posterior pole — described as a "rainbow" or "peacock" sheen, and highly suggestive of a complicated rather than a senile cataract

Treat and control the underlying disease first. In uveitic cataract the eye should be quiet for at least 3 months before surgery, with inflammation suppressed by topical, systemic or immunosuppressive treatment
Perioperative steroid cover is essential — topical and often systemic steroid started several days before surgery and continued and tapered slowly afterwards.
Surgical difficulties in a uveitic eye — a small, poorly dilating pupil bound by posterior synechiae, requiring synechiolysis, iris hooks or a pupil expander; a pupillary membrane needing excision; band keratopathy obscuring the view, which may need chelation first; zonular weakness; a fibrosed or calcified anterior capsule; and a high rate of after-cataract

Look for the cause before you look at the lens; a complicated cataract is a sign, and the disease behind it determines both treatment and prognosis
Wait for three months of quiescence in a uveitic eye, and give perioperative steroid cover; operating on an inflamed eye guarantees a poor result
Warn about the guarded prognosis; macular oedema and optic neuropathy limit the outcome whatever the surgeon does, and expectations must be set honestly
Recognise glaukomflecken; they are permanent evidence of a past acute angle-closure attack and may be the only clue in a patient who never sought help
Expect nuclear sclerosis after vitrectomy and warn the patient at the time; it develops in most adults within a few years

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