Purpose:
To determine the agreement between Moorfield Regression Analysis(MRA), Glaucoma Probability Score(GPS)of HRT III and parapapillary nerve fibers thickness values provided by the OCT i-Vue.
Methods:
39 patients(72 eyes) affected by ocular hypertension and/or early POAG undergone achromatic 30° visual field (VF) with Octopus Prog.G1X dynamic strategy.54 eyes with normal VF and 18 with early VF damage were included in the study.HRT III and OCT i-Vue were done and MRA,GPS and OCT values related to infero-temporal (IT), infero-nasal (IN), supero-temporal(ST), supero-nasal(SN), nasal(N), temporal(T) quadrant of the optic disc and nerve fibers were considered, evaluating the percentages of normality (n), abnormality (a) and borderline (b) provided by the instruments. For MRA and GPS, global evaluation was also considered. Percentages of concordance(n-n;b-b;a-a),relative concordance (n-b;b-a) and discordance (a-n) obtained with the different methods were calculated in relation to the degree of VF damage,considering each quadrant individually.Kappa statistic was used to assess the agreement between methods.Kappa range from 0.262 to 0.72.
Results:
In normal VF patients HRT showed(n) of MRA and GPS respectively of 63% and 28.5%,(b) of 24% and 28.5% and (a) of 11% and 41%.In early damage VF,percentages were respectively 16,6% and 33,3%, for (n), 27,7% and 33,3% for (b) and 55,5% and 33,3% for (a).Relative correlation of the parameters tested with MRA, GPS and i-Vue in the eyes with normal and early damage VF are summarized in tables I and II.
Conclusions:
MRA was revealed as being the most sensitive and specific method of correlation between anatomic and functional damage. The comparison among the various techniques showed a better correlation between MRA and i-Vue parameters both in normal and abnormal VF.Moreover the higher percentages of concordance per quadrant of the MRA and of the OCT i-Vue confirm that in early glaucoma the damage first affects the fibers originating from the temporal hemi-retina.
Keywords: nerve fiber layer • optic disc • intraocular pressure