Attempted eyelid closure affects intraocular pressure measurement

PURPOSE: To evaluate the effect of attempted eyelid closure on intraocular pressure measurement. METHODS: Normal subjects underwent intraocular pressure measurement in both eyes using Goldmann applanation tonometry and Tono-pen XL (Mentor, Inc, No rwell, Massachusetts) by the same examiner holding the eyelids open, both w ith and without the subject simultaneously attempting forced eyelid closure . Subjects were seated during all measurements and waited 5 minutes between measurements with each instrument; the order of measurement was randomized . RESULTS: Thirty eyes of 15 subjects (six men, nine women) were enrolled. Me an age was 30.5 +/- 5.2 years (range, 24 to 40 years). With Goldmann applan ation tonometry, intraocular pressure increased in both eyes with attempted eyelid closure by a mean of 1.5 +/- 2.0 mm Hg (P = .0002, paired t test; r ange, -2 to 8 mm Hg). With the Tono-pen XL, intraocular pressure also incre ased in both eyes with attempted eyelid closure by a mean of 1.9 +/- 2.7 mm Hg (P = .0002, paired t test; range, -2 to 9 mm Hg), Tone-pen XL mean intr aocular pressure values in both eyes (14.4 +/- 2.3 mm Hg) consistently over estimated those of Goldmann applanation tonometry (13.0 +/- 2.2 mm Hg) by a mean of 1.4 +/- 2.3 mm Hg. CONCLUSIONS: Attempted forced eyelid closure is a common and statistically significant source of error in routine outpatient measurement of intraocula r pressure and could influence clinical management of glaucoma. (Am J Ophth almol 2001;131:417-420. (C) 2001 by Elsevier Science Inc. All rights reserv ed).