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Editor,—We report a case of a 45 year old man with chronic renal failure presenting with symptomatic bilateral acute raised intraocular pressure (IOP) following haemodialysis. The pressures were successfully reduced with a topical β blocker and following the commencement of regular topical treatment his symptoms were controlled with no further record of raised IOPs.
A 45 year old white man was referred to the eye casualty department by the renal physicians, complaining of bilateral blurred vision and a dull frontal headache following haemodialysis. The blurred vision resolved spontaneously within 2 hours of onset but the headache persisted. The headaches had been recurrent following every haemodialyses which he had undergone and could last up to 10 hours. The blurred vision was a less consistent feature, only occurring occasionally. He had end stage renal failure due to glomerulonephritis and had been commenced on haemodialysis three times a week. There was no relevant past ocular or family history of note. On examination unaided visual acuities were 6/5 in both eyes. The eyes were quiet and the corneas were clear. There was no relative afferent pupillary defect. The anterior chamber depths were estimated at 2.6 mm in both eyes using the Smith method.1 The right IOP was 42 mm Hg and the left was 36 mm Hg. The angles were open at grade 3–4 using the Shaffer grading system with no peripheral anterior synechiae in both eyes.2 There was no evidence of pigment dispersion. There was no significant elevation of IOPs following pupil dilatation. Both discs were healthy with good neuroretinal rims. We treated the raised ocular pressures with levobunolol 0.5% eye drops alone. Systemic carbonic anhydrase inhibitor was relatively contraindicated in renal failure. Within 1 hour the headache had resolved and the IOP decreased to 24 mm Hg in the right and 18 mm Hg in the left. Subsequently we arranged to measure his IOPs before and after haemodialysis to establish a causal relation. Before haemodialysis the IOPs were 18 mm Hg in the right and 16 mm Hg in the left. Following haemodialysis, the IOPs were 32 mm Hg and 28 mm Hg in the right and left eye, respectively. Consequently he was commenced on levobunolol 0.5% twice daily and since then his symptoms have improved markedly with minimal headaches and no visual disturbances.
Symptomatic raised IOP following haemodialysis is rarely diagnosed. Asymptomatic raised IOP following haemodialysis has been reported in the medical literature. Several studies have shown that raised IOP follows haemodialysis in a significant number of patients while others have failed to show this relation.3-6 The prevalence of this phenomenon among patients undergoing haemodialysis is not known and the pathophysiology involved is not certain. The elevation of IOP may be due to a decrease in outflow facility and an osmotic influx of water into the eye because of hyperosmolality of intraocular fluids following dialysis.4 In all the studies, the raised IOP was of questionable clinical significance. All except one patient who had a history of narrow angle glaucoma were asymptomatic. To our knowledge this is the first case reported of symptomatic acutely raised intraocular pressure following haemodialysis in a patient who had previously healthy eyes. Carbonic anhydrase inhibitor is relatively contraindicated in this condition as it can precipitate severe metabolic acidosis.5 Regular topical β blocker can be used to control this condition.