Katarak Traumatika

01Pathophysiology

The crystalline lens is an avascular, transparent structure enclosed in an elastic capsule. Its transparency depends on the highly organized arrangement of lens fiber proteins (crystallins) and on the integrity of the capsule, which acts as a semipermeable barrier controlling water and electrolyte flux.

In blunt (concussive) trauma, the force of impact is transmitted through the aqueous humor and compresses the lens in its anteroposterior axis, causing it to expand equatorially. This mechanical deformation can rupture zonular fibers (producing subluxation or dislocation) and can damage lens epithelial cells without breaching the capsule. The injured epithelial cells undergo disorganized proliferation and abnormal fiber differentiation, producing the characteristic rosette or stellate opacity in the posterior subcapsular region. This is why you can see a classic flower-petal pattern weeks to months after the initial injury, even when the capsule remains intact. A ring-shaped imprint of iris pigment on the anterior capsule, called a Vossius ring, forms at the moment of impact when the pupillary margin is slammed against the lens surface.

In penetrating trauma, the lens capsule is physically breached. Aqueous humor floods into the lens substance, causing rapid hydration and swelling of lens fibers (intumescent cataract). The cortical material becomes opaque quickly, sometimes within hours. If the capsular tear is small, it may self-seal with fibrin, and the opacity may remain localized. A large tear leads to total cortical opacification and can release lens proteins into the anterior chamber, triggering phacoanaphylactic (lens-induced) uveitis or phacolytic glaucoma from macrophage-laden protein clogging the trabecular meshwork.

Chemical injuries, particularly alkali burns, penetrate deeply because alkali agents saponify cell membranes. The alkaline pH directly denatures crystallin proteins, causing diffuse opacification. Acid burns tend to coagulate surface proteins, limiting deeper penetration, which is why alkali injuries produce more severe cataracts than acid injuries of comparable exposure.

The key teaching concept: the pattern of opacity tells you the mechanism. A rosette points to blunt concussive force; a localized cortical white plaque points to a capsular breach; and total white intumescence points to a large capsular rupture with aqueous influx.

02Classification and Clinical Manifestation

03Diagnostic Workup

Every patient with a traumatic cataract begins with a thorough slit-lamp examination. You are looking for the pattern of lens opacity (which tells you blunt vs. penetrating mechanism), the status of the anterior chamber (cells, flare, hyphema), and whether the capsule is intact. Measure IOP in both eyes to screen for secondary glaucoma.

If the fundus view is obscured by a dense cataract or vitreous hemorrhage, order B-scan ultrasonography to rule out retinal detachment and posterior segment foreign bodies. If there is any suspicion of a penetrating mechanism or history of hammering, grinding, or blast injury, obtain a CT of the orbits with thin axial cuts. MRI is absolutely contraindicated when a metallic foreign body is suspected, as the magnetic field can mobilize the fragment and cause further damage.

Gonioscopy should be performed once the eye is quiet enough to allow it. Angle recession affecting more than 180 degrees of the angle carries a long-term risk of secondary open-angle glaucoma, sometimes presenting years after the initial trauma. This is a frequently tested concept: a patient who had blunt eye trauma decades ago now presents with unilateral elevated IOP and open angles on gonioscopy.

04Management and Treatment

The first priority is never the cataract itself. You must stabilize the globe and control inflammation before planning lens surgery. If there is an open globe injury, primary repair of the corneal or scleral laceration takes precedence. Intracameral or intravitreal antibiotics (vancomycin 1 mg/0.1 mL + ceftazidime 2.25 mg/0.1 mL) are given at the time of primary repair if endophthalmitis risk is high.

Once the globe is intact, start topical prednisolone acetate 1% hourly during waking hours and atropine 1% three times daily. Atropine stabilizes the blood-aqueous barrier, reduces pain from ciliary spasm, and prevents the formation of posterior synechiae (iris adhesions to the swollen lens).

If a retained intraocular foreign body is confirmed on CT, it must be removed, usually within 24 to 48 hours. Iron-containing foreign bodies cause siderosis bulbi (progressive retinal toxicity from iron deposition), while copper foreign bodies above 85% purity cause suppurative endophthalmitis, and those below 85% purity cause chalcosis with a characteristic sunflower cataract.

For lens-induced glaucoma (either phacomorphic from an intumescent lens pushing the iris forward, or phacolytic from macrophage-laden lens protein clogging the trabecular meshwork), the next best step is urgent cataract extraction after temporizing IOP with medical therapy.

Elective cataract surgery is planned after at least 3 months of a quiet eye. Zonular integrity must be assessed preoperatively (look for iridodonesis, phacodonesis, or UBM findings). If zonular dialysis involves less than 3 to 4 clock hours, a capsular tension ring (CTR) inserted during surgery distributes stress and supports the capsular bag. For extensive zonular loss, a scleral-fixated IOL or iris-fixated IOL may be needed.

In children, the surgery is more urgent because of the risk of deprivation amblyopia. For children under approximately 2 years of age, primary IOL implantation is generally avoided because of unpredictable refractive growth; instead, the child is left aphakic and corrected with a contact lens. Aggressive amblyopia management with patching of the fellow eye is mandatory postoperatively.

05Differential Diagnosis and Distractors

06Traps and High-Yield Pearls

The most common way students lose points on traumatic cataract questions is by rushing to surgical management before stabilizing the eye. The vignette may describe a young patient with a penetrating globe injury, an obvious white cataract, and poor vision, tempting you to choose "cataract extraction with IOL" as the next best step. The correct answer in an acute setting is primary globe repair first, followed by anti-inflammatory therapy, and then cataract surgery weeks to months later once the eye is quiet. Surgery on an inflamed eye leads to fibrin membranes, posterior synechiae, and poor visual outcomes.

Another classic trap involves a patient presenting with unilateral elevated IOP years after blunt ocular trauma. Students often overlook angle recession glaucoma because the trauma history may be buried early in the stem. The gonioscopy finding of a widened ciliary body band in the affected eye compared to the fellow eye is the discriminator.

Watch for the sunflower cataract vignette: a metalworker with gradually worsening vision and a green-gold anterior subcapsular deposit. This is chalcosis from a retained copper-containing IOFB, and the next step is CT orbit to locate the foreign body, not just cataract surgery.

Finally, in pediatric traumatic cataracts, the tested concept is not just the surgery but the postoperative amblyopia management. If the question asks about the most important factor determining long-term visual prognosis in a 3-year-old with a unilateral traumatic cataract, the answer is adherence to amblyopia therapy (patching and optical correction), not the surgical technique itself.

The core competency being tested across all traumatic cataract questions is your ability to recognize the mechanism from the opacity pattern, sequence the management correctly (stabilize, then operate), identify secondary complications (glaucoma, IOFB toxicity, endophthalmitis), and understand that in children, the real battle is against amblyopia.