This is a comparative study between ultrahigh molecular weight polyethylene (UHMWPE) reinforced with micro-and nano-hydroxyapatite (HA) under different filler content. The micro-and nano-HA/UHMWPE composites were prepared by hotpressing method, and then compression strength, ball indentation hardness, creep resistance, friction, and wear properties were investigated. To explore mechanisms of these properties, differential scanning calorimetry, infrared spectrum, wettability, and scanning electron microscopy with energy dispersive spectrometry analysis were carried out on the samples. The results demonstrated that UHMWPE reinforced with micro-and nano-HA would improve the ball indentation hardness, compression strength, creep resistance, wettability, and wear behavior. The mechanical properties for both micro-and nano-HA/UHMWPE composites were comparable with pure UHMWPE. The mechanical properties of nano-HA/UHMWPE composites are better compared with micro-HA/UHMWPE composites and pure UHMWPE. The optimum filler quantity of micro-and nano-HA/UHMWPE composites is found to be at 15 wt % and 10 wt %, separately. The micro-and nano-HA/UHMWPE composites exhibit a low friction coefficient and good wear resistance at this content. The worn surface of HA/UHMWPE composites shows the wear mechanisms changed from furrow and scratch to surface rupture and delamination when the weight percent of micro-and nano-HA exceed 15 wt % and 10 wt %.

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Purpose To investigate the morphological and functional reconstruction of the macular fovea after autologous neurosensory retinal transplantation for recurrent macular hole retinal detachment (MHRD) in highly myopic eyes. Methods Ten consecutive cases of recurrent MHRD with high myopia were retrospectively reviewed. All eyes underwent pars plana vitrectomy combined with autologous neurosensory retinal transplantation and were followed up for at least 3 months after silicone oil extraction. The main outcomes were whether or not the retina was reattached and the macular hole (MH) was closed, morphological changes in the retinal graft, best‐corrected visual acuity (BCVA), the sensitivity threshold and blood flow signal in the macula. Results At the one month postoperative visit, there was an obvious boundary between the graft and the surrounding retinal tissue, and some retinal structural layers could be seen in the graft on optical coherence tomography scans. At the final follow‐up, eight eyes (80%) showed retinal reattachment and closure of the MH. Optical coherence tomography revealed blurring of the boundary between the graft and surrounding retinal tissue and that the retinal structure in the graft was disordered. The MH was not closed in two eyes (20%), in one case because of partial displacement of the graft and in the other because of incomplete coverage of the MH as a result of a smaller graft. The post‐BCVA was significantly better than the pre‐BCVA (1.32 ± 0.33 versus 2.01 ± 0.29 logMAR; p = 0.000, paired t‐test). Conclusion Autologous neurosensory retinal transplantation can be an effective treatment for recurrent MHRD in highly myopic eyes. ‘Fusion’ between the neurosensory retinal graft and the original retinal tissue may be the mechanism involved in the closure of the MH and reconstruction of the macular fovea.

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