Hypotensive Effect of Dynamic Electroneurostimulation in Patients with Primary Open-Angle Glaucoma

Bakutkin V.V., Bakutkin I.V.

Vision Correction Center, Saratov, Russia

Actuality.

Glaucoma is the main cause of irreversible blindness. Number of patients with primary open-angle glaucoma increases yearly, in Russia they reach 3.5 – 4.0%, in USA – 6.0 – 7.0% from the total number of people (Libman E.S., 2005). This disease is characterized with increase of intraocular tension which causes development of optic nerve atrophy. Problem of glaucoma treatment consists of two important aspects – normalization of intraocular tension and treatment of existing optic nerve atrophy. Traditionally, local hypotensive medications from the group of adrenoceptor blocking drugs are used to lower an intraocular tension (thymolol maleat, betoptic and other analogous medications). Their effect is based on liquid outflow improvement through the drainage system of the eye and small decrease of intraocular liquid production by ciliary body. There are some other medications that appeared only in recent times and are used rarely. Travatan group (prostaglandin’s inhibitor) improves liquid outflow through the uveal tract, Asopt from the carbanhydrase group of local effect decreases intraocular liquid production. All these medications have been used for a long period of time and can have numerous side effects (worsening of blood supply, disturbance of metabolism of anterior segment of the eye tissues) (Egorov E.A., 2005).

For some patients who have bronchial asthma and heart diseases these medications are contra-indicated. As a result dominant method of intraocular tension normalization is surgical one. Operations of drainage type are carried out and artificial ways of intraocular liquid outflow are created. Inspite of high efficiency of these methods, some complications could exist, including severe enough to cause worsening of visual functions. Transcutaneous electrostimulation method in treatment of ophthalmologic patients is used more than 10 years already (Bakutkin V.V., 1995, Gileva E.V., 1997). There is a definite necessity in creation of therapeutic methods of treatment in order to lower an intraocular tension and to stimulate an optic nerve.

Purpose of the research.

To study an influence of the DENS-therapy on the level of intraocular tension in patients with open-angle glaucoma.

Materials and methods of the research.

122 patients with primary open-angle glaucoma in the age from 52 to 78 years old were studied. Duration of the glaucoma disease was from 1.5 to 16 years. Patients were diagnosed with glaucoma basing on the anamnesis data and the results of full clinical investigation which included research of the central vision acuity, research of the peripheral field of vision and the static perimetry on the SYNIMED equipment (USA), contactless tonometry in dynamics (daily during all the treatment course) on the pneumatonometer REICHERT (USA), colormetrical analysis of the disk of optic nerve on the retinofot CARL ZEISS, biomicroscopy of the anterior segment of the eye and fundus of the eye.

Compensated and subcompensated level of IOT, absence of corresponding ophtalmological diseases were considered to be indications for the treatment realization. Treatment was carried out with the help of VIDENS apparatuses with the trailing electrode glasses. Treatment course made up to 10 sessions 3 to 10 minutes long. Level of impact was 4-5 with frequency 77 Hz.

Results of the research.

Endurance of the DENS-therapy was good. Patients didn’t have any complaints. Influence of the DENS-therapy on the level of intraocular tension was studied before and after the therapy session during the entire treatment course. Significant difference in reaction on the DENS-therapy was noticed during the treatment course in patients with different stages of glaucoma. The most decrease of the level of intraocular tension (up to 5 mm of mercury) was discovered after first 3 sessions of DENS-therapy in patients with first stage of glaucoma (42 patients).

Picture 1. Dynamics of the level of intraocular tension in patients with 1, 2, 3 stages of glaucoma during the DENS-therapy application.

For the patients with the second stage of glaucoma (40 patients) decrease of the level of IOT was noticed in 34 people; 6 patients didn’t show any change of IOT level. After the DENS-therapy session level of IOT decreased in average on 2.5 mm of mercury (this difference is statistically reliable). For people with the third stage of glaucoma decrease of the IOT was noticed only in 20 out of 40 patients. Certain inertance with respect to reaction on the DENS-therapy was noticed. The average level of pressure decrease made up 2.5 mm of mercury. After 5-6 session the IOT level normalized and fluctuations were 1-2 mm of mercury for all categories of patients. There were no cases of decompensation of IOT level during treatment course. Some patients with first stage of glaucoma showed pressure oscillation within the limits of daily physiological rate. Difference in the level of pressure before and after the treatment are statistically reliable (P is less than 0.05). It became possible to cancel the local hypotensive therapy for 15 patients as a result of intraocular tension normalization.

Results of the research and discussion.

Only DENS impact on the level of IOT is considered in this work as the most important index of the eyes’ condition in patients with glaucoma. IOT lowering on 5.0 mm of mercury at the first stage is an evidence of existing reserve of drainage system of an eye. Almost analogous hypotensive effect could be reached using local medications from the thymolol maleat group. Such level of pressure lowering could call out an assumption about the action mechanism of stimulation on the ciliary muscle (radial part of fibers of Brukke muscle). IOT level changed less when reserve of the drainage system of an eye was lowered at the 2 and 3 stages of glaucoma which are characterized with organic lesion of outflow tract of intraocular liquid. DENS-therapy didn’t cause any side effects, that’s why it should be considered more preferable than traditional local therapy in drops.

Conclusion.

An impact of DENS-therapy on IOT indexes of patients with primary open-angle glaucoma was studied. The most high hypotensive effect was achieved in patients with first stage of glaucoma. DENS-therapy could be recommended as a method of non-medication hypotensive remedy for patients with compensated and subcompensated level of intraocular tension.

Sources.

Libman E.S. Materials of VIII Congress of Russian Ophthalmologists. 2005. pp. 3 – 5.

Gileva E.V. “Transcutaneous Electrostimulation in Treatment Patients with Glaucoma Atrophy of Optic Nerve”. Thesis of Candidate of Medicine. 1997. (Scientific leader Bakutkin V.V.).