STRUCTURAL GLAUCOMATOUS DAMAGE vs VISUAL FIELD DEFECTS: LONGITUDINAL STUDY IN PATIENTS WITH OCULAR HYPERTENSION OR EARLY PRIMARY OPEN ANGLE GLAUCOMA (POAG)

T.Rolle, B. Brogliatti, A. Fea, E. Borasio, A. Fornero, L. Belli and
 M. Manea

Department of Ophthalmology, University of Turin, ITALY

Purpose. To evaluate the changes in the morphology of the optic nerve head (ONH) and of the RNFL and in the visual field in a group of patients with ocular hypertension or early POAG. All eyes included in this study presented at the baseline IOP values >22 mm Hg.

Patients and methods. A total of 17 patients (24 eyes) were enrolled in a prospective longitudinal study. The mean follow up period was 427,6+-161,2 days. Patients with disease other than glaucoma that could have affected the appearance of the optic disc or visual field were carefully excluded. The ONH morphology and the RNFL were evaluated by HRT (software 2.01) at the beginning and at the end of the follow up; the visual field examination (Octopus 500, Gl program, Peritrend analysis) was carried out at the same time of the HRT. All patients included in the study had at least two previous exams with RF< 15% ; Patients were excluded if the average baseline visual field mean defect (MD) was 6 dB or more; 7 eyes did not show a visual fмeld damage. During the follow up period all patients have been treated with topical antiglaucomatous therapy.

The optic disc and RNFL variables and the perimetic indices (MD and CLV) were analysed both globally and segmentally. The statistical analysis was performed with the t test and ANOVA. The correlation between HRT parameters and VF indices was evaluated with the Pearson test (r).

Results. At the end of the follow up period all eyes showed a progression in the visual field defects from the baseline values (p<0.05). The 7 eyes with ocular hypertension converted to early glaucoma. The HRT parameters evaluated both globally and segmentally presented a progression in the structural damage not statistically significant. The correlation with the MD was good for the following HRT parameters: CA, C/D ratio, CSM.

Conclusions. The progression of the functional damage could be caused by the morphological alterations registered at the baseline also in the 7 eyes with OH. The lack of a significant progression of structural glaucomatous damage could be due to the good tonometric control with antiglaucomatous therapy.