Optic nerve damage in highly myopic eyes with chronic open-angle glaucoma.
OBJECTIVE
To compare the amount of optic nerve damage in relation to intraocular pressure in highly myopic eyes with chronic open-angle glaucoma versus non-highly myopic eyes with chronic open-angle glaucoma.


METHODS
The comparative clinical observational study included 1841 eyes of 1100 patients with chronic open-angle glaucoma. The highly myopic study group consisted of 25 eyes with a myopic refractive error equal to or higher than -8 diopters. It was subdivided into eyes with an optic disc size larger than 2.7 mm2 and eyes with an optic disc smaller than 2.7 mm2. The control group included the remaining, non-highly myopic eyes (n=1816). For all patients, a morphometric analysis of color stereo optic disc photographs was performed. Main outcome measures were morphometric optic disc measurements and intraocular pressure.


RESULTS
In the highly myopic, large-optic-disc study group compared with the control group, maximal and minimal intraocular pressure readings were significantly (p<0.05) lower and neuroretinal rim area corrected for optic disc size was slightly (p=0.16) smaller. Comparing the total highly myopic study group with a control group adjusted for optic disc area, neuroretinal rim area was significantly (p=0.039) smaller in the study group with no significant difference in intraocular pressure measurements between the groups.


CONCLUSIONS
At a given intraocular pressure in chronic open-angle glaucoma, optic nerve damage may be more pronounced in highly myopic eyes with large optic discs than in non-highly myopic eyes. This may suggest a higher susceptibility for glaucomatous optic nerve fiber loss in highly myopic eyes than in non-highly myopic eyes.
Jonas
J B
JB
Department of Ophthalmology and Eye Hospital, Faculty of Clinical Medicine Mannheim, University of Heidelberg, Mannheim, Germany. Jost.Jonas@augen.ma.uni-heidelberg.de
Budde
W M
WM
D002908:Chronic Disease; D005260:Female; D005902:Glaucoma, Open-Angle / Q000150:complications* / Q000175:diagnosis; D006801:Humans; D007429:Intraocular Pressure; D008297:Male; D008875:Middle Aged; D047728:Myopia, Degenerative / Q000150:complications*; D009898:Optic Disk / Q000473:pathology; D009901:Optic Nerve Diseases / Q000175:diagnosis / Q000209:etiology*; D012307:Risk Factors