Abstract |
Purpose: To evaluate macula nerve fibre layer thickness, in glaucoma suspects (GS), early
glaucoma patients (EMG) and controls, using optical coherence tomography. Also correlate
central corneal thickness, intraocular pressure, axial length and PSD in each diagnostic group.
Method: A total of 35 participants (70 eyes), 9 normal subjects, 14 glaucoma suspects and
12 early glaucoma patients, with mean age 59,2 ± 9,3 years were enrolled. The selection of the
participants was based on the standards of Ocular Hypertension Treatment Study and
European Glaucoma Prevention Study. The study included the following measurements,
central corneal thickness, intraocular pressure (Goldman and Pascal tonometer), axial length,
pattern standard deviation (VF), total mean macula thickness at 6,0mm over the macula, in 4
quadrants (inf, sup, nas, temp) and mean macula nerve fibre layer thickness at 3mm distance
over the macula, in 4 quadrants (inf, sup, nas, temp) measured by Stratus OCT. After the
previous exams, the calculation of thickness ratio, as the quotient of mean macula nerve fibre
layer thickness to total mean macula thickness followed.
All the subjects underwent a full ophthalmic examination, including medical history (ocular
and family histories), visual acuity, intraocular pressure measurement with Goldman and
Dynamic Contour tonometry, biometry, pachymetry, Humphrey 24-2 visual field testing,
dilated slit-lamp examination with stereoscopic biomicroscopy of the optic nerve head (ONH)
and NFL and optical coherence tomography.
Patients with diabetic retinopathy history, macula oedema, age related macula degeneration,
neurological diseases, retinal surgery procedure, cataract operation, PRK and Lasik procedure,
corneal oedema and scars, were excluded.
In all subjects, no differences in glaucoma progress were observed, between two eyes.
Results: According to our study, macular thickness was significantly thinner in the EMG
eyes than in normal eyes for all four quadrants (inf, sup, nas, temp).The m-RNFL thickness
was significantly reduced in GS eyes than in normal eyes for inferior quadrant. No significant
difference was detected for ratio thickness. IOP measurements by GAT are highly concordant
with IOP readings obtained by DCT, neither GAT nor DCT showed a significant correlation
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with CCT. No significant difference was detected for IOP, CCT, Axial Length, PSD between
the three groups.
Conclusions: Macula atrophies due to glaucoma are already known, as optic disk atrophy is.
In the future it’s important to use new scanning protocols to detect early glaucoma abnormalities
in peripheral macula regions, as glaucoma atrophies there, seems to be more severe.
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