Diurnal variation in intraocular pressure (IOP) is well recognized, yet important decisions in glaucoma management are frequently made after 1 or 2 IOP measurements. Twenty-four-hour monitoring of IOP may identify IOP variation and spikes. This study determined the value of 24-hour IOP monitoring in routine clinical practice.
Data were acquired retrospectively from case notes of 29 glaucoma patients sequentially admitted for 24-hour IOP monitoring while taking their established antiglaucoma therapy.
While there was no difference between the mean clinic (office) and mean 24-hour IOP measurements, the peak IOP during 24-hour monitoring was on average 4.9 mm Hg higher than the peak clinic IOP (P <0.0001). In 4 (13.8%) patients, the peak IOP over 24 hours was at least 12 mm Hg higher than the clinic peak. Peak IOP values occurred outside normal office hours in 51.7% of patients. Twenty-four-hour IOP monitoring resulted in a change of clinical management in 23 (79.3%) patients, including 13 (44.8%) who were offered trabeculectomy.
Twenty-four-hour monitoring of IOP frequently led to a change of glaucoma management by identifying IOP fluctuations and spikes. High IOP and wide diurnal IOP variation are considered major risk factors for glaucoma progression, and standard clinic follow-up evaluations failed to identify these phenomena.
Department of Ophthalmology Bristol Eye Hospital, Bristol, United Kingdom
Received November 13, 2002;
sent for revision January 15, 2003; accepted February 24, 2003.
None of the authors has any proprietary interest in any therapeutic agents or diagnostic aids mentioned in this study.
Address correspondence and reprint requests to E. H. Hughes, Bristol Eye Hospital, Lower Maudlin Street, Bristol, BS1 2LX, UK. E-mail: firstname.lastname@example.org