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The morphology and mechanical properties of binary blends of nylon 6 (N6), as the major component, and ethylene‐methacrylic acid copolymers (E/MAA), as the minor component, have been analyzed. It was found that the methacrylic acid content of the copolymer used as the second component has a profound effect upon the properties of the resulting blends. In particular, with increasing methacrylic acid content, the size of the domains of the E/MAA dispersed phase in the N6 matrix decreased in a regular fashion while the ultimate tensile properties increased regularly. This behavior has been attributed to a series of chemical and physico‐chemical interactions taking place between the two components. The interactions are due to the presence of the acid functionality on the copolymer and do not occur when this functionality is absent. Chemical analysis of the blends was performed to confirm that chemical modification took place during the blending process.

Internal limiting membrane (ILM) abrasion is an alternative surgical technique for successful full-thickness macular hole (MH) repair. OBJECTIVE To study the effects of ILM abrasion as an alternative method of MH repair. DESIGN, SETTING, AND PARTICIPANTS Retrospective consecutive case series from January 2006 to December 2008. Demographic data and preoperative, intraoperative, and postoperative examination records of all patients were reviewed for patients who underwent ILM abrasion with a diamond-dusted membrane scraper during vitrectomy for MH repair. A total of 100 eyes underwent ILM abrasion as an alternative to traditional ILM peeling. MAIN OUTCOMES AND MEASURES Rate of MH closure and visual acuity (VA) outcomes at 3 months after surgery.RESULTS Macular hole closure was achieved with a single surgical procedure in 94 of 100 eyes (94.0%; 95% CI, 87.4%-97.8%). Among all patients, the median preoperative VA was 20/100 (range, 20/30 to hand motions; 25th quartile, 20/60; and 75th quartile, 20/160), and the median postoperative VA at 3 months after surgery was 20/60 (range, 20/20 to hand motions; 25th quartile, 20/40; and 75th quartile, 20/100). Among all patients with stage 2 MHs, 30 of 38 patients (78.9%) had at least 2 lines of VA gain: 15 of 23 (65.2%) were phakic, and 15 of 15 (100%) were pseudophakic. Four of 38 patients (10.5%) with stage 2 MHs had at least 2 lines of VA loss, and all were phakic. Among all patients with stage 3 or 4 MHs, 42 of 62 (67.7%) had at least 2 lines of VA gain, of which 30 of 38 (78.9%) were phakic and 22 of 24 (91.7%) were pseudophakic. Six of 62 patients (9.7%) with stage 3 or 4 MHs had at least 2 lines of VA loss: 4 were phakic, and 2 were pseudophakic. In total, 35.0% (95% CI, 25.7%-44.3%) of patients achieved 20/40 vision or better, and 52.0% (95% CI, 42.2%-61.8%) of patients achieved 20/50 vision or better.CONCLUSIONS AND RELEVANCE Abrasion of the ILM with a diamond-dusted membrane scraper at the time of vitrectomy achieves high rates of MH closure. This technique avoids complete removal of the retinal ILM basement membrane and subjacent tissues and appears to provide MH closure rates similar to those of traditional ILM peeling.

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