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The EPIRET3 system can be successfully implanted and explanted in patients with blindness and RP. The surgical steps are feasible, and the postoperative follow-up disclosed an acceptable range of adverse events.

Corneal transplantation is the treatment of choice for patients with advanced corneal diseases. However, the outcome may be affected by graft rejection, high associated costs, surgical expertise, and most importantly the worldwide donor shortage. In recent years, bioprinting has emerged as an alternative method for fabricating tissue equivalents using autologous cells with architecture resembling the native tissue. In this study, we propose a freeform and cell‐friendly drop‐on‐demand bioprinting strategy for creating corneal stromal 3D models as suitable implants. Corneal stromal keratocytes (CSK) were bioprinted in collagen‐based bioinks as 3D biomimetic models and the geometrical outcome as well as the functionality of the bioprinted specimens were evaluated after in vitro culture. We showed that our bioprinting method is feasible to fabricate translucent corneal stromal equivalents with optical properties similar to native corneal stromal tissue, as proved by optical coherence tomography. Moreover, the bioprinted CSK were viable after the bioprinting process and maintained their native keratocyte phenotypes after 7 days in in vitro culture, as shown by immunocytochemistry. The proposed bioprinted human 3D corneal models can potentially be used clinically for patients with corneal stromal diseases.

The high correlation of NIR fluorescence and reflectance indicated that part of the observed NIR fluorescence is pseudofluorescence, whereas gray-scale analysis indicated that both NIR autofluorescence and pseudofluorescence contribute to the NIR fluorescence images. Quantification of leakage of the imaging system indicated a significant part of the observed NIR fluorescence is NIR autofluorescence. As NIR fluorescence derives from pigmented lesions, melanin is a possible source if NIR reflectance is also increased. Comparison with blue-light-excited autofluorescence showed differences between AMD and patients with nevi. NIR autofluorescence was also detected in single cases of maculopathy without corresponding NIR reflectance.

In the widely used mouse model of retinal degeneration, rd1, the loss of photoreceptors leads to rhythmic electrical activity of around 10–16 Hz in the remaining retinal network. Recent studies suggest that this oscillation is formed within the electrically coupled network of AII amacrine cells and ON-bipolar cells. A second mouse model, rd10, displays a delayed onset and slower progression of degeneration, making this mouse strain a better model for human retinitis pigmentosa. In rd10, oscillations occur at a frequency of 3–7 Hz, raising the question whether oscillations have the same origin in the two mouse models. As rd10 is increasingly being used as a model to develop experimental therapies, it is important to understand the mechanisms underlying the spontaneous rhythmic activity. To study the properties of oscillations in rd10 retina we combined multi electrode recordings with pharmacological manipulation of the retinal network. Oscillations were abolished by blockers for ionotropic glutamate receptors and gap junctions. Frequency and amplitude of oscillations were modulated strongly by blockers of inhibitory receptors and to a lesser extent by blockers of HCN channels. In summary, although we found certain differences in the pharmacological modulation of rhythmic activity in rd10 compared to rd1, the overall pattern looked similar. This suggests that the generation of rhythmic activity may underlie similar mechanisms in rd1 and rd10 retina.

Rhegmatogenous retinal detachment is among the main emergency indications in ophthalmology. In all such cases, an ophthalmologist must be consulted at once.

No abstract

Background: Macular rotation surgery comprises surgical extraction of choroidal neovascular membranes in age-related macular degeneration (AMD) and translocation of the foveal neural retina over adjacent retinal pigment epithelium.Objective: To determine whether macular translocation with 360°retinotomy can stabilize and/or improve visual acuity in patients with subfoveal choroidal neovascularization (CNV) secondary to AMD.Design: This study consisted of a standardized surgical procedure on a series of 90 consecutive patients and follow-up examinations at fixed intervals for 12 months.Participants: All patients in this study had experienced recent visual loss resulting from subfoveal CNV caused by AMD. Twenty-six patients had major macular subretinal hemorrhage, 39 patients had occult subfoveal CNV, and 25 patients had classic subfoveal CNV.Methods: Macular translocation surgery was performed between 1997 and 1999. The patients were examined preoperatively and at 3, 6, and 12 months postoperatively, including visual acuity, microperimetry, angiography, and orthoptic assessment.Results: Visual acuity increased by 15 or more letters in 24 patients, remained stable in 37 patients, and deteriorated by 15 or more letters in 29 patients at 12 months postoperatively. A secondary procedure was necessary in 17 patients because of severe complications; proliferative vitreoretinopathy was observed in 17 eyes, macular pucker in 5 eyes, and macular hole in 1 patient. Conclusion:Macular translocation is a technically demanding surgical procedure. Although the procedure has a high rate of surgical and postoperative complications, the functional and anatomical results appear to be promising for selected patients with subfoveal CNV secondary to AMD.