ABSTRACT
@#AIM: To assess the changes of foveal avascular zone(FAZ)and vessel density(VD)using optical coherence tomography angiography(OCTA)in diabetic retinopathy(DR)patients.<p>METHODS: A systematic review of the literature was performed to examine the diagnostic used OCTA in DR to date. Six electronic databases were searched to find relevant studies. We conducted a literature search in English and Chinese databases. Two authors extracted basic data, the VD of superior capillary plexus(VD<sub>SCP</sub>), the VD of deep capillary plexus(VD<sub>DCP</sub>), the area and the perimeter of FAZ. We used a variety of Meta-analytic methods, including <i>WMD</i> forest maps, funnel plot, Begg test and sensitivity analysis, to confirm the final results.<p>RESULTS: Totally 24 studies recruiting 2 305 eyes were included. Patients with DR showed statistical difference in VD<sub>SCP </sub>\〖<i>WMD</i>= -5.78, 95%<i>CI </i>(-7.67 to -3.88), <i>P</i><0.05\〗, VD<sub>DCP</sub> \〖<i>WMD</i>= -5.08, 95%<i>CI</i>(-6.49 to -3.67), <i>P</i><0.05\〗, the perimeter of FAZ \〖<i>WMD</i>=0.57, 95%<i>CI</i>(0.36 to 0.78), <i>P</i><0.05\〗, the area of FAZ \〖<i>WMD</i>=0.08, 95%<i>CI </i>(0.06 to 0.10),<i> P</i><0.05\〗 with healthy controls. <p>CONCLUSION: In general, there was a trend towards a larger area and longer perimeter of FAZ in patients with DR. It can also be concluded that the VD of FAZ is higher in healthy controls. While questions remain regarding OCTA practical applicability in its present form, with continuing development and improvement of the technology, the diagnostic value of OCTA in DR is likely to become evident.
ABSTRACT
@#AIM: To evaluate the predictability of Olsen formula for postoperative refractive power in patients with high myopia complicated with cataract.<p>METHODS: This retrospective study reviewed 65 patients(101 eyes)with high myopia and who had phacoemulsification combined with intraocular lens implantation from October 10th 2016 to August 20th 2019 in our hospital. They were divided into three groups according to the axis length: group A(26mm <AL≤28mm)17 cases(29 eyes), group B(28mm<AL≤30mm)26 cases(41 eyes), group C(AL>30mm)22 cases(31 eyes). The postoperative theoretical diopter(that is, the preoperative predictive diopter of each formula corresponding to the degree of IOL implanted)of intraocular lens was calculated by SRK/T, Haigis and Olsen formulas of IOL-master. The actual postoperative 3mo diopter was recorded and the absolute refractive error(MAE)was calculated.<p>RESULTS: The postoperative 3mo MAE in the three groups calculated with Olsen formula was 0.15(0.04, 0.22), 0.19(0.14, 0.27), 0.26(0.115, 0.455)D respectively(<i>P</i>>0.05). For patients with the same axial length, the postoperative 3mo MAE of Olsen formula was the smallest. The Bland-Altman method was used to analyze the consistency between the postoperative theoretical diopter and the postoperative 3mo actual diopter. The results showed that the postoperative 3mo actual diopter was the closest to the postoperative theoretical diopter of the Olsen formula, while the postoperative theoretical diopter of the SRK/T formula was the worst.<p>CONCLUSION: For patients with high myopia and cataract, the accuracy and stability of Olsen formula is better than that of SRK/T and Haigis formula, and Olsen formula is least affected by eye axis length.