No abstract

Silicone oil tamponade is widely used in the surgical treatment of retinal detachments. The article provides analysis of mechanical forces exerted to the retina in various parts of the vitreous cavity. There are areas of tamponade effect insufficiency, in which it may be beneficial to create additional means which would support the retina keeping it attached to the pigment epithelium. The aim of the study was to develop a new technique desired to keep the retina attached in the areas where retina lacks effective tamponade effect of silicone oil. The technology is desired to be implemented in challenging cases of retinal detachments caused by giant retinal breaks, retinodialysis, or in patients with hard-to-remove epiretinal membranes in proliferative vitreoretinopathy. Materials and Methods. The proposed technique-magnetic scleral buckling-is able to exert pressure to the retina by the means of mutual magnetic attraction of the magnetic scleral buckle (outer buckle) sutured to the retina and endovitreal magnetic buckles (inner buckles) made of magnetoactive elastomer and placed onto the retina in the projection of the outer magnetic buckle. A series of ex vivo experiments was performed to elaborate the technique using isolated cadaver donor eyes: we performed magnetic scleral buckling and then subtotal vitrectomy with iatrogenic detaching of retina followed by implantation of endovitreal magnetic buckles (inner buckles) made of magnetoactive elastomers to provide additional mechanical support for the retina. Results. Elastic properties of the magnetic scleral buckles didn't differ from those of common scleral buckles. Endovitreal magnetic buckles fitted well onto the retina, smoothly, tightly and effectively held it pressing against the pigment epithelium. We tried buckles of various sizes and shapes and chose the best fitted for endovitreal manipulations. Endovitreal buckles securely supported the retina and could be easily removed with 25G vitreotome. Conclusion. The developed technique of magnetic scleral buckling allowed to keep retina securely reattached with magnetic forces as was shown during ex vivo experiments. Further in vivo studies of the technique are required.

Scleral buckling (SB) has been regaining its popularity in the treatment of retinal detachments. On large clinical material, it has been proved to be the technique of choice in phakic patients with retinal detachment of moderate severity. A combined procedure that incorporates features of episcleral as well as intravitreal surgeries has also become widely used. Aim - to investigate the prospects for increasing technical potential of SB, particularly, to investigate the possibility of additional atraumatic mechanical fixation of the retina from within the vitreous cavity. The proposed device consists of an episcleral magnetic buckle and endovitreal magnetic buckles (endobuckles). The episcleral magnetic buckle is made of medical grade silicone and cannot be distinguished from common buckles, except that it contains one or more permanent magnets on the basis of neodymium-iron-boron powders. Endobuckles are small flat elastic elements made of silicone elastomer filled with magnetic particles. Еndobuckles are implanted into the vitreous cavity through a small pars plana incision and placed on the retina at the projection of the scleral magnetic buckle. Thus, in experiments with cadaver eyes, the authors have showed the principle feasibility of retinal fixation by the force of magnetic interaction between the magnetic scleral buckle and endobuckles. The described technique of additional mechanical fixation of the retina provides wider surgical opportunities in the management of retinal detachments.

No abstract

No abstract