Abstract
Purpose :
Cases of reccurent retinal detachments with severe proliferative vitreoretinopathy (PVR) are still challenging for the surgeon. We tested the feasibility of a new surgical technique for the treatment of RD complicated with severe PVR: 360° magnetic scleral buckling (mSB) combined with pars plana vitrectomy (PPV) using human donor cadaver eyes.
Methods :
Eleven (11) human donor cadaver eyes were operated. Retinal detachment was simulated by tearing retina off the ora serrata. mSB was a procedure comprising of 2 steps: 1st - scleral buckling with the buckle having permanent magnets inside (pic. 1) and 2nd(performed after PPV) - implantation of magnetoactive endobuckles into the vitreous cavity. Endobuckles were small flat magnetoactive elements made of silicone elastomer filled with iron particles less than 20 µm in diameter and had saturation magnetization 50 – 220 Gs cm3/g. Endobuckles had a form that allowed to arrange them to continuous curved contours. Endobuckles were implanted into the vitreous cavity through a microincision with the help of injector system and placed on the retina at the projection of scleral magnetic buckle (pic. 2). Endobuckles were able to be removed by 25G vitreotome.
Results :
The force of magnetic interaction between the magnetic scleral buckle and the magnetoactive endobuckles provided support for the retina. Properties of the magnetic scleral buckle (flexibility, elasticity) were the same as conventional scleral buckle. The optimal pressure exerted to the retina by endobuckles was estimated as 307Pa and was possible to achieve with endobuckles of 0.12 mm in thickness and 1,2-1,3 mm in width, and outer magnetic buckle with neodymium magnets of 3 mm in diameter and 1 mm in thickness placed in series in one row 1 mm apart.
Conclusions :
The magnetic scleral buckling technique is feasible and potentially useful providing additional support for the retinal areas affected with severe PVR. In vivo studies are required to evaluate the potential for clinical applicability of the described surgical technique.
This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.