[Influence of antihypertensive therapy on morphofunctional and biomechanical parameters of eyes].

Unlabelled: SHORTHEADER: biomechanical parameters of the eye on antihypertensive therapy.

Purpose: to establish correlation of main biomechanical parameters of cornea depends on conducted antihyperthensive therapy and morphofunctional condition of cornea.

Material And Methods: 58 patients (62 eyes) with POAG were included in the dynamic study in the period from 36 to 42 months. Patients were divided into two groups depending on the values of corneal hysteresis (CH) in the first part of the study. The value of CH in the first group (37 eyes) was in normal ranges 8,3-12,4 mm of mercury, in the second group (25 eyes) CH value has been reduced to 5.6-8.2 mm of mercury. In the second part of the study brimonidine/ timolol fixed combination (Combigan, Allergan) was prescribed as adjunctive therapy for the patients from the group 2 with low CH level. The following scheme of instillations was recommended--1 drop 2 times a day with interval of 12 hours. We evaluated the subjective and objective measures of structural and functional condition of the eye after 1, 3, 6, 12 and 18 months.

Results: In the first part of the study of the dynamics of morphological and functional parameters of the optic nerve at different values of the CH, it was found that if CH < 8.2 mm of mercury structural and functional changes of optic nerve are more pronounced and significantly increases the risk of progression of glaucomatous process that requires correction of antihypertensive treatment. In the second part of the study in a group of dynamic observation with low CH level considering the negative structural and functional dynamics of antihypertensive therapy was corrected by Combigan® administration. Add-on therapy (Combigan) had a statistically significant effect on IOP, lowering it at average on 4.6 mm of mercury, and on the CH level, increasing it at average on 2.3 mm of mercury. Analysis of changes in perimeter sLV index showed a reduction of numbers of relative defects of various depths (from 8.9 dB to 6.9 dB). Analysis of optical coherent retinotomography data with brimonidine/timolol instillation on the background showed a tendency to increase the average thickness of retinal nerve fibers (from 0.11 to 0.18 mm). Dynamic observation for 18 months showed the stability of structural and functional parameters of the optic nerve disc, i.e. the target pressure for these patients has been achieved.

Conclusion: Administration of fixed combination brimonidine/timolol (Combigan) in combined therapy for the patients with POAG and low level of CH leads to normalization of biomechanical parameters of the eye and stabilization of glaucomatous process.