Evaluating the efficacy of Quantum Molecular Resonance (QMR) electrotherapy in mixed-type dry eye patients.

PURPOSE: To evaluate the efficacy and safety of the low-power, high-frequency electrical current treatment administered by the Rexon-Eye device, in a cohort of patients affected by mixed-type dry eye disease (DED) of medium to severe level. PATIENTS AND METHODS: In this prospective, non-randomized, interventional clinical study, eighteen mixed type DED patients were treated. Treatment was a specific type of electrotherapy, Quantum Molecular Resonance (QMR®), administered by means of the Rexon-Eye® device (Resono Ophthalmic, Sandrigo, Italy) with a protocol of one 20-min session per week, for 4 weeks. Patients were examined at baseline and one month after the last treatment, utilizing the Ocular Surface Disease Index (OSDI) questionnaire and clinical signs: non-invasive tear break-up time (NIBUT), Oxford staining, meibum quality, meibography, meibomian gland expressibility, tear meniscus height (TMH), Schirmer's test, ocular inflammation expressed by MMP-9 concentration. RESULTS: Subjective benefit in OSDI was reported (p = 0.013). Improvement was also observed in NIBUT (p < 0.001), Oxford staining (p = 0.002), expressible meibomian glands number (p = 0.001) and meibum quality (p < 0.001). A remarkable benefit was present in inflammation, as evidenced by the reduction of MMP-9 (p = 0.003). Changes, although not statistically significant, were also present in TMH (p = 0.076) and Schirmer's test (p = 0.675), whereas no change was observed in meibography score. No adverse event was reported. CONCLUSION: In this mixed-type DED patients' cohort, Rexon-Eye proved to be effective and safe in improving subjective and objective ocular parameters, as well as capable to normalize inflammatory markers.

High Frequency Electrotherapy for the Treatment of Meibomian Gland Dysfunction.

PURPOSE: To test the safety and efficacy of high frequency electrotherapy (ET) on the clinical signs and symptoms of patients affected by dry eye and meibomian gland dysfunction (MGD). METHODS: Twenty-five patients affected by MGD were enrolled. Quantum Molecular Resonance ET was administered by means of the Rexon-Eye device 4 times, once per week for 4 weeks. Patients were reexamined 1 month after the last treatment. The primary endpoint was reduction in corneal fluorescein staining. Additional endpoints were tear break-up time, Ocular Surface Disease Index score, meibomian gland secretion score, and the number of expressible meibomian glands. Safety endpoints were Logarithm of the Minimum Angle of Resolution (LogMar) best spectacle-corrected visual acuity and intraocular pressure. RESULTS: Corneal fluorescein staining improved by 62.5% (P < 0.0001), tear breakup time increased by 30.9% (P < 0.0001), and the Ocular Surface Disease Index score improved by 37% (P < 0.001). The meibum quality and the number of expressible meibomian glands also increased (35.7% and 12%, P < 0.001 and P < 0.0001, respectively). Schirmer test scores increased after treatment by 16.5% (P = 0.01). No adverse events were observed. CONCLUSIONS: Quantum Molecular Resonance ET appears to be safe and significantly reduces symptoms and signs associated with MGD. It may have a relevant role in the treatment of evaporative dry eye disease.

Transcutaneous periorbital electrical stimulation in the treatment of dry eye.

PURPOSE: To evaluate efficacy and safety of transcutaneous application of electrical current on symptoms and clinical signs of dry eye (DE). METHODS: 27 patients with DE underwent transcutaneous electrostimulation with electrodes placed onto the periorbital region of both eyes and manual stimulation with a hand-piece conductor moved by the operator. Each patient underwent 12 sessions of 22 min spread over 2 months, two sessions per week in the first month and one session per week in the second month. Ocular Surface Disease Index (OSDI) questionnaire, tear break-up time (TBUT), fluorescein staining of the cornea, Schirmer I test and adverse events were evaluated at baseline, at end of treatment and at 6 and 12 months. RESULTS: OSDI improved from 43.0±19.2 at baseline to 25.3±22.1 at end of treatment (mean±SD, p=0.001). These effects were substantially maintained at 6-month and 12-month follow-up evaluations. Improvement of the values of TBUT was recorded for the right eye at the end of treatment (p=0.003) and found in the left eye after 12 months (p=0.02). The Oxford scores changed in both eyes at the end of treatment and at the 6-month evaluation (p<0.001), and in the right eye at the 12-month evaluation (p=0.035). Schirmer I improved significantly at the end of treatment in the left eye (p=0.001) and in both eyes at the 12-month evaluation (p=0.004 and p=0.039 for the left and right eye, respectively). A significant reduction of the use of tear substitutes was found at the end of treatment (p=0.003), and was maintained during the follow-up (p<0.001).No complications occurred and patients found the treatment satisfying. CONCLUSIONS: Transcutaneous electrical stimulation was shown to improve DE, both subjectively and objectively, without any adverse effects and has the potential to enlarge the armamentarium for treating DE.

Impact of temporary hyperthermia on corneal endothelial cell survival during organ culture preservation.

To evaluate temporary exposure to hyperthermia for its impact on endothelial cell density of porcine corneas in organ culture medium containing dextran with regards to possible negative influences of high temperatures during the storage and transport of corneal grafts. Four groups of central discs (diameter 8 mm) from the corneas of both eyes in 40 pigs were first organ-cultured (MEM with 6% dextran 500) for 24 h at 32°C. Ten corneas were then exposed to 40°C in group 1, to 42°C in group 2, to 44°C in group 3, and to 50°C in group 4 for 12 h each. The paired corneal discs for all groups were not treated, stored at 32°C and served as controls. After further organ culture of all corneas for 48 h at 32°C to allow regenerative processes, corneal endothelium was stained with Alizarin Red S and examined by light microscopy. The endothelial cell densities were determined on three central images using a system for the automatic estimation of morphometric parameters of corneal endothelium. Exposure for 12 h to 40°C as well as to 42°C induced no endothelial cell loss. Statistical analysis showed no significant difference of the endothelial cell density between corneas exposed to 40°C and 42°C and the control corneas (40°C treatment: 4736 ± 426 cells/mm(2) and control: 4762 ± 344 cells/mm(2), p = 0.74; 42°C treatment: 4240 ± 363 cells/mm(2) and control: 4176 ± 448 cells/mm(2), p = 0.40). Exposure to 44°C and 50°C lead to total necrosis of the endothelial cell layer. Exposure of organ cultured porcine corneas in dextran containing medium up to 42°C for 12 h does not compromise the endothelial cell density in a clinically relevant manner. Temperatures above 42°C, as it might be the case during transports from the cornea bank to the ophthalmic surgeon, must be strictly avoided as they damage the endothelial cell layer.