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PHACOLYTIC GLAUCOMA Signs and symptoms The patient with phacolytic glaucoma is typically elderly with a history of progressively worsening vision from pre-existing cataracts. Vision typically is reduced to light perception range, but the patient may have no light perception due to a hypermature cataract and the glaucomatous process.1 There may be movement of the lens as the patient's eye moves (phacodonesis), indicating a loss of zonular support. The patient will experience ocular pain, sometimes quite severe. There will be anterior segment inflammation with an anterior chamber reaction. A hypermature lens is invariably present. The intumescence of the lens prevents observation of the fundus ophthalmoscopically. Intraocular pressure is elevated and asymmetric. Due to the types of inflammatory cells present, development of synechiae is uncommon. Pathophysiology Internal lens proteins gain access to the anterior chamber through the phacolytic process involving the hypermature cataract. There is liquefaction of the lens nucleus and cortex, and attenuation of the capsule with the release of lens proteins into the anterior chamber. While the lens proteins are the host's own body tissue, they have never been exposed to the anterior chamber due to their envelo pment by the lens capsule. Thus, the body detects these lens proteins as foreign and antigenic. Subsequently, an inflammatory reaction ensues with a lens-induced uveitis. Ultrastructural study of aqueous and vitreous aspirates shows lenticular fragments and macrophages with lipofuscin granules and phagocytic vacuoles containing lens proteins.2 Numerous macrophages having phagocytized degenerated lens material (phacolytic cells) can be found in the anterior chamber, and free-floating degenerated lens material is also conspicuous.3 These constituents mechanically produce trabecular obstruction and dysfunction with subsequent rise in IOP. Management
Secondary glaucoma accompanying phacolysis is often improved by the reduction in inflammation with topical steroid therapy. However, if additional pressure reduction is necessary, aqueous suppressants are advocated, provided there are no systemic contraindications. How-ever, miotics and prostaglandins should be avoided due to their propensity to aggravate the disease. In most cases, it is necessary to remove the antigenic lens in order to fully manage phacolytic glaucoma. Commonly, extracapsular and even intracapsular cataract extraction are used to remove the antigenic lens. Either anterior or posterior chamber intraocular lens implantation can be an option.4 In cases of long duration prior to surgery, trabeculectomy may additionally be needed in order to control IOP.5 Removal of the antigenic lens and control of the glaucoma should be done quickly. One study found that patients over 60 years and in whom the glaucoma was present for more than five days had a significantly higher risk of poor visual outcome post-op.6 The addition of trabeculectomy to cataract extraction is typically unnecessary in the control of IOP in patients with phacolytic glaucoma operated on within two to three weeks of the onset of symptoms. Light perception without projection is not a contraindication for cataract surgery in phacolytic glaucoma.7 Clinical Pearls
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Eyelids & Eyelashes | Conjunctiva & Sclera | Cornea
Uvea | Vitreous & Retina | Neuro-Ophthalmic
Disease | Oculosystemic Disease
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