Describe the secondary glaucomas.

Secondary Open-angle Glaucomas

• Pseudoexfoliation syndrome — a systemic fibrillopathy in which a greyish-white fibrillar material is deposited throughout the anterior segment and in systemic tissues including the heart, lung, liver and skin. It is the commonest identifiable cause of secondary open-angle glaucoma worldwide
• Its ocular signs — a "target" pattern on the anterior lens capsule: a central disc, a clear intermediate zone (swept clear by the moving iris) and a peripheral granular band, seen best after dilation; deposits on the pupillary margin; peripupillary iris transillumination defects; heavy, irregular trabecular pigmentation with a sampaolesi line (pigment anterior to Schwalbe line); and, critically, poor dilation and zonular weakness
• Its surgical importance — pseudoexfoliation predicts a difficult cataract operation: a small pupil, weak zonules with a risk of capsule rupture and dropped nucleus, and late in-the-bag lens dislocation years afterwards. Recognising it before surgery changes the plan

Secondary Angle-closure Glaucomas

• Neovascular glaucoma — considered separately, and much the most important
• Phacomorphic glaucoma — an intumescent cataract producing pupil block and acute closure. It presents exactly like a primary acute attack, and is distinguished by the obvious cataract and, decisively, by the normal, open angle in the fellow eye. Treated by pressure control and then urgent cataract extraction, which is curative
• Uveitic angle closure — from seclusio pupillae with iris bombe, or from extensive peripheral anterior synechiae

Applied Aspects

• Dilate to look for pseudoexfoliation; the target pattern on the lens capsule is invisible through an undilated pupil and it changes the surgical plan
• Do gonioscopy in every glaucoma patient; angle recession, neovascularisation, synechiae, heavy pigment and blood in Schlemm canal are all invisible without it
• Ask about exercise-related blurring in a young myopic man; pigment-dispersion spikes are characteristic and the diagnosis is otherwise missed
• Ask about steroids by every route, including skin creams and inhalers; patients do not regard these as medicines and do not volunteer them
• Monitor the pressure lifelong after any blunt ocular injury; angle recession glaucoma appears decades later and is entirely silent
• Check the fellow eye angle in any acute attack; a normal open fellow angle means the cause is secondary, and phacomorphic
• Suspect ice syndrome in unilateral glaucoma with iris changes in a young woman; the corneal endothelial appearance confirms it
• Think of topiramate in a young patient with bilateral acute myopia and shallow chambers; stopping the drug reverses it and an iridotomy does not help
• Pseudoexfoliation is a systemic fibrillopathy, deposited in heart, lung and skin as well as the eye, and is associated with vascular disease
• The Sampaolesi line is pigment anterior to Schwalbe, and is a useful gonioscopic marker of pseudoexfoliation
• Pseudoexfoliative glaucoma progresses faster with higher pressures and wider diurnal swings than primary open-angle disease
• Laser trabeculoplasty works especially well in pseudoexfoliation, because of the heavy trabecular pigmentation
• The Krukenberg spindle is vertical, formed by aqueous convection carrying pigment down the endothelium
• Pigmentary glaucoma may burn out with age as the lens thickens and the iris flattens.
• A third of the population are steroid responders, and the rise appears after two to six weeks of treatment
• Children and myopes respond more strongly to steroid, and a family history of glaucoma raises the risk further
• Steroid glaucoma is reversible if caught early, which is why the pressure must be checked in anyone on prolonged treatment
• Distinguish the mechanism in uveitic glaucoma; trabeculitis, steroid response, synechial closure and pupil block need different treatments
• Angle recession is a wide ciliary body band on gonioscopy, and is compared with the fellow eye to be certain
• Ghost cells are khaki-coloured degenerate red cells from an old vitreous haemorrhage, obstructing the meshwork directly
• Blood in Schlemm canal means raised episcleral venous pressure, and should prompt a search for a fistula or an orbital cause