[Surgical treatment for optic neuropathy in high myopia].

AIM: To improve the effectiveness of surgical treatment for optic neuropathy in high-degree myopia. MATERIAL AND METHODS: A total of 54 patients (96 eyes) aged 18-30 with high myopia and signs of optic neuropathy were observed. The main group consisted of 20 patients (28 eyes) who underwent meridional scleral reinforcement with type I collagen-based implant placed over the posterior segment. The control group included 34 patients (68 eyes) who were given a 10-day vitamin and vascular therapy course. In most of the controls (21 patient, 21 eyes) indirect revascularization with ligation of the superficial temporal artery was performed. Ophthalmological examination was done before the beginning of the treatment and then at 1, 6, and 12 months. Results. At the end of the follow-up period best corrected visual acuity in the main group was 19.2% higher, on average, than baseline values, but remained unchanged in the controls. Light sensitivity of the retina in both group increased by 7% and 2% respectively. Electrically evoked phosphene thresholds decreased by 22.5% and 10.4% respectively. The main group also demonstrated a near-constant mean peripapillary nerve fiber layer (RNFL) thickness and a 16.4% higher than baseline blood flow velocity in the ophthalmic artery. In the control group the latter parameter showed no change. CONCLUSIONS: Scleral reinforcement surgery in patients with high myopia complicated by optic neuropathy enables improvement of visual functions and regional blood flow as well as stabilization of RNFL thickness and volume, thus, preventing subsequent development of optic nerve atrophy.

Medical devices; ophthalmic devices; classification of the scleral plug. Final rule.

The Food and Drug Administration (FDA or Agency) is classifying the scleral plug into class II (special controls), and exempting the scleral plugs composed of surgical grade stainless steel (with or without coating in gold, silver, or titanium) from premarket notification (510(k)) and continuing to require premarket notification (510(k)) for all other scleral plugs in order to provide a reasonable assurance of safety and effectiveness of the device. The scleral plug is a prescription device used to provide temporary closure of a scleral incision during an ophthalmic surgical procedure.

An experimental study on collagen content and biomechanical properties of sclera after posterior sclera reinforcement.

BACKGROUND: The development of pathological myopia is associated with reduced scleral collagen accumulation, scleral thinning, and loss of scleral tissue, in both humans and animal models. Posterior scleral reinforcement (PSR) was considered as an effective way for treating pathological myopia. Yet it is not well understood the possible role of collagen on the sclera reinforcement mechanisms in the PSR surgery. METHODS: PSR surgery was performed on the normal adult New Zealand white rabbits eyes. Human sclera was used as reinforcement materials. At 1, 2, 3, 6, 9 months after the PSR surgery, scleral hydroxyproline (Hyp) synthesis and collagen fibers arrangement were determined by enzymolysic hydrolysis assay and histological morphology technique. An Instron test machine was used to investigate the elastic modulus of sclera. FINDINGS: It was found that the elastic modulus and Hyp content of reinforced sclera were lower at first month after surgery, and then gradually up to physiological level in the following months. Those two indexes were close to that of the normal control groups at 9 months. INTERPRETATION: These findings indicate that sclera elastic modulus was associated with both change of Hyp content and collagen fibers arrangement after PSR. The therapeutic effect of PSR surgery was confirmed not only from biological but also biomechanical aspects.

[The optimization of a surgical intervention to stabilize progressive myopia]. / Optimizatsiia khirurgicheskogo vmeshatel'stva s tsel'iu stabilizatsii progressiruiushchei blizorukosti.

Results of 236 sclera-fortifying surgeries are followed up for more than 25 years. Progressive myopia stabilized in 95.8% cases after bandaging scleroplasty and in 87.03% cases after chondroplasty. Clinical refraction and posteroanterior axis of the eye did not increase after surgery; visual functions stabilized, and brightness sensitivity threshold was lowered. The technique of operation and clinical course of the postoperative period are described. Based on analysis of the clinical material, the authors propose the optimal approach to scleroplastic operations aimed at stabilization of progressive myopia.