Menzel-Severing Johannes, Sellhaus Bernd, Laube Thomas, Brockmann Claudia, Bornfeld Norbert, Walter Peter, Roessler Gernot
Department of Ophthalmology, RWTH Aachen University, Aachen, Germany.
Ophthalmic Res. 2011 Oct;46(4):192-8. doi: 10.1159/000324650. Epub 2011 Apr 5.
For the purpose of visual rehabilitation of subjects with photoreceptor degeneration, an implantable microelectronic device for epiretinal stimulation was developed. Our study aimed to show whether implantation and explantation could be conducted safely and to investigate tissue compatibility.
The device was implanted in 5 Göttinger minipigs. Four weeks later, the implant was surgical- ly removed. Histopathological examination that followed aimed at detecting inflammatory or proliferative changes. Stains used were hematoxylin and eosin, leukocyte common antigen, CD68 and glial fibrillary acidic protein. A grinding technique was used to visualize the retinal tissue in conjunction with the retinal tacks.
The implantation of the devices was successful in all cases. The explantation was complicated by intraoperative hemorrhages. Complete explantation could only be achieved after modifying the implantation strategy. Histopathology revealed a mild degree of cystic disaggregation of the retina. Immunohistochemically, an increased glial fibrillary acidic protein expression of Müller cells was found, which shows a moderate glial cell activation. Inflammatory cells were absent. Using the grinding technique, tissue adjacent to the retinal tacks showed a mild gliosis.
The viability of implantation and explantation of the implant in minipigs has been shown. The absence of immunoreactive cells or a considerable glial reaction suggest that the device may be considered safe and suitable for further implantation in humans.
为了使光感受器变性患者获得视觉康复，研发了一种用于视网膜前刺激的可植入微电子设备。我们的研究旨在表明植入和取出手术是否能够安全进行，并研究组织相容性。
将该设备植入5只哥廷根小型猪体内。四周后，通过手术取出植入物。随后进行组织病理学检查，旨在检测炎症或增殖性变化。使用的染色剂为苏木精和伊红、白细胞共同抗原、CD68和胶质纤维酸性蛋白。采用研磨技术结合视网膜钉来观察视网膜组织。
所有病例的设备植入均成功。取出手术因术中出血而变得复杂。只有在修改植入策略后才能完全取出。组织病理学显示视网膜有轻度囊性分离。免疫组织化学检查发现，米勒细胞的胶质纤维酸性蛋白表达增加，表明存在中度胶质细胞活化。未发现炎性细胞。使用研磨技术，视网膜钉附近的组织显示有轻度胶质增生。
已证明该植入物在小型猪体内植入和取出的可行性。未发现免疫反应性细胞或明显的胶质反应，这表明该设备可能被认为是安全的，适合进一步植入人体。
