24-Hour Intraocular Pressure Fluctuation Suppressed by Microhook Trabeculotomy in Ocular Hypertension: A Case Report

A 76-year-old woman was referred to our hospital for evaluation of markedly high intraocular pressures (IOPs): ≥40 mmHg in both eyes. No intraocular inflammation, pseudoexfoliation, or glaucomatous optic neuropathy was observed on ophthalmological examination. The 24-hour IOP fluctuations, measured with a Goldmann tonometer in the sitting position at 8, 12, 16, 20, and 24 o'clock, were 22/17, 33/28, 41/33, 30/22, and 30/24 mmHg, respectively, and showed a peak in the afternoon. The patient was diagnosed with ocular hypertension, and microhook trabeculotomy (μLOT) (right eye with lens reconstruction, left eye initially pseudophakic) was performed. After μLOT surgery in both eyes (4 days postoperatively in the right eye and 1 day postoperatively in the left eye), IOP decreased in both eyes to 12/15, 11/14, 12/15, 10/11, and 10/10 mmHg, and the fluctuation range was suppressed. At 3 months postoperatively (measured at 8, 12, 16, 20, 24, and 4 o'clock), the effect was maintained at 14/15, 15/19, 14/19, 11/12, 13/14, and 13/13 mmHg, respectively, but was slightly attenuated. In a patient with marked 24-hour IOP fluctuation, μLOT was effective in reducing IOP values and fluctuation.