TY - JOUR T1 - Effect of acute intraocular pressure elevation on the minimum rim width in normal, ocular hypertensive and glaucoma eyes JF - British Journal of Ophthalmology JO - Br J Ophthalmol SP - 131 LP - 135 DO - 10.1136/bjophthalmol-2017-310232 VL - 102 IS - 1 AU - Sourabh Sharma AU - Tin A Tun AU - Mani Baskaran AU - Eray Atalay AU - Sri Gowtham Thakku AU - Zhang Liang AU - Dan Milea AU - Nicholas G Strouthidis AU - Tin Aung AU - Michael JA Girard Y1 - 2018/01/01 UR - http://bjo.bmj.com/content/102/1/131.abstract N2 - Background To estimate and compare changes in the Bruch’s membrane opening—minimum rim width (BMO–MRW) and area in normal, ocular hypertensive and glaucoma eyes following acute elevations in intraocular pressure (IOP).Methods The optic nerve heads (ONHs) of 104 subjects (31 normals, 20 ocular hypertension (OHT) and 53 with primary glaucoma) were imaged using Spectral-domain optical coherence tomography (OCT; Spectralis, Heidelberg Engineering, Germany). IOP was raised twice by applying a force (0.64 n then 0.9 n) to the anterior sclera using an ophthalmo-dynamometer. After each IOP increment, IOP was held constant, measured with a Tonopen (AVIA applanation tonometer, Reichert, Depew, New York, USA), and ONH was rescanned with OCT. In each OCT volume, BMO–MRW and area were calculated and at each IOP increment.Results The baseline MRW was significantly smaller in glaucoma subjects (174.3±54.3 µm) compared with normal (287.4±42.2 µm, p<0.001) and OHT subjects (255.4±45.3 µm, p<0.001). MRW of glaucoma subjects was significantly thinner at the first and second IOP elevations than that at baseline (both p<0.01), but no significant change was noted in normal and OHT subjects. There was no significant change of BMO area at acute IOP elevations from baseline in all diagnoses (all p>0.05).Conclusion Acute IOP elevation leads to compression of the nerve fibre layers of neuroretinal rim in glaucoma subjects only without changing ONH size. This suggests that the neural and connective tissues at ONH level in glaucoma subjects are more susceptible to acute IOP episodes than OHT or normal controls. ER -