Three-year results of small incision lenticule extraction and wavefront-guided femtosecond laser-assisted laser in situ keratomileusis for correction of high myopia and myopic astigmatism

AIM： To compare and calculate the 3-year refractive results, higher-order aberrations （HOAs）, contrast sensitivity （CS） and dry eye parameters after small incision lenticule extraction （SMILE） and wavefront-guided femtosecond laser-assisted laser in situ keratomileusis （FS-LASIK） for correction of high myopia and myopic astigmatism. METHODS： In this prospective, non-randomized comparative study, 78 eyes with spherical equivalent （SE） of -8.11±1.09 diopters （D） received a SMILE surgery, and 65 eyes with SE of -8.05±1.12 D received a wavefront-guided FS-LASIK surgery with the VisuMax femtosecond laser （Carl Zeiss Meditec, Jena, Germany） for flap cutting. Visual acuity, manifest refraction, CS, HOAs, ocular surface disease index （OSDI） and tear break-up time （TBUT） were evaluated during a 3-year follow-up. RESULTS： The difference of uncorrected distance visual acuity （UDVA） postoperatively was achieved at lmo and at 3mo, whereas the difference of the mean UDVA between two groups at 3y were not statistically significant （t=-1.59, P=-0.13）. The postoperative change of SE was 0.89 D in the FS-LASIK group （t=5.76, P=0.00）, and 0.14 D in the SMILE group （t=-0.54, P=0.59） from lmo to 3y after surgery. At 3-year postoperatively, both HOAs and spherical aberrations in the SMILE group were obviously less than those in the FS-LASIK group （P=0.00）, but the coma root mean square （RMS） was higher in the SMILE group （0.59±0.26） than in the FS-LASIK group （0.29±0.14, P=0.00）. The mesopic CS values between two groups were not statistically significant at 3y postoperatively. Compared with the FS-LASIK group, lower OSDI scores and longer TBUT values were found in the SMILE group at Imo and 3mo postoperatively. With regard to safety, no eye lost any line of CDVA in both groups at 3y after surgery. CONCLUSION： Both SMILE and wavefront-guided FS- LASIK procedures provide good visual outcomes. Both procedures are effective and safe, but SMILE surgery achieve more stable long-term refractive outcome and better control of early postoperative dry eye as compared to FS-LASIK.

Serum microRNA-221 as a biomarker for diabetic retinopathy in patients associated with type 2 diabetes

AIM: To investigate the candidate microRNA(miRNA), miR-221 as a novel biomarker for diabetic retinopathy(DR) in patients associated with type 2 diabetes(T2D).METHODS: The subjects involved were divided into four groups: healthy control(HC), no diabetic retinopathy(NDR), non-proliferative diabetic retinopathy(NPDR) and proliferative diabetic retinopathy(PDR) group. Serum miR-221 was validated by real-time quantitative reversetranscription polymerase chain reaction(qRT-PCR). Also, serum angiotensin II(Ang II) and vascular endothelial growth factor(VEGF) were examined by enzyme-linked immunosorbent assay. In addition, receiver operating characteristic(ROC) curve was performed to explore the diagnostic accuracy of miR-221, Ang Ⅱ and VEGF for DR in patients with T2D. Spearman’s rank correlation coefficient was executed to estimate the correlations of serum miR-221 with metabolic parameters and serum markers in patients with T2D.RESULTS: Primarily, serum miR-221, Ang Ⅱ and VEGF were increased significantly in T2D patients compared to HC participant respectively, and progressive up-regulated in NDR, NPDR and PDR groups(P<0.001). Additionally, miR-221 in serum was remarkably positively correlatedwith metabolic parameters such as glycated hemoglobin(r=0.310, P=0.002) and homeostasis model assessment for insulin resistance(r=0.413, P<0.001), as well as serum markers for instance Ang Ⅱ(r=0.667, P<0.001) and VEGF(r=0.499, P<0.001). Furthermore, serum miR-221(AUC, 0.894; 95%CI, 0.833-0.955; P<0.001), Ang Ⅱ(AUC, 0.888; 95%CI, 0.828-0.949; P<0.001) and VEGF(AUC, 0.785; 95%CI, 0.695-0.875; P<0.001) had evidently diagnostic efficiency in DR, and miR-221 is the most effective among them.CONCLUSION: Serum miR-221 as a potential biomarker could be related to not only occurrence but also progression for DR in patients with T2D. However, a prospective clinical trial is warranted.