Efficacy of C3F8 versus silicone oil tamponade in highly myopic macular hole retinal detachment / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To compare the outcome of C3F8 versus silicone oil tamponade after pars plana vitrectomy(PPV)and inverted internal limiting membrane(ILM)for the treatment of highly myopic macular hole retinal detachment(MHRD).METHODS: Retrospective clinical study. Totally 45 patients(45 eyes)with highly myopic MHRD who visited our hospital between January 2019 and August 2022 were selected as the research subjects. The patients were divided into two groups according to different intraocular tamponade agents: C3F8(22 eyes)and silicone oil(23 eyes)groups. All patients underwent conventional three-incision PPV, ILM was tamped, a venous blood clot was placed on the tamped ILM, and 15% C3F8 and silicone oil were used as tamponade, respectively. The best corrected visual acuity(BCVA), multifocal electroretinogram(mfERG), the closure of the macular hole, retinal reattachment and the complications were observed.RESULTS: The macular hole closure rate was 77% in the C3F8 group and 83% in the silicone oil group, respectively(P>0.05), and retinal reattachment rates were 95% and 96%, respectively(P>0.05). The visual acuity of the two groups significantly improved, which was 0.99±0.34 and 1.22±0.37, respectively, and the C3F8 group was better than that of the silicone oil group(t=-2.156, P=0.037). After operation, the response density of the first ring of P1 wave in the first order kernel in mfERG was 114.27±26.37 nV/deg2 for the C3F8 group and 98.08±24.36 nV/deg2 for the silicone oil group, and the response density of the second ring of P1 wave was 80.45±14.94 nV/deg2 for the C3F8 group and 67.73±15.33 nV/deg2 for the silicone oil group, all of which were significantly higher compared to pre-operation [the response density of the first ring of P1 wave: 58.13±13.96 nV/deg2 for the C3F8 group and 55.30±10.48 nV/deg2 for the silicone oil group, the response density of the second ring of P1 wave: 51.18±8.19 nV/deg2 for the C3F8 group and 47.43±11.97 nV/deg2 for the silicone oil group](all P<0.05). It was found that the response density of the first ring of P1 wave was lower in the silicone oil group than in the C3F8 group(P<0.05). There was no statistically significant difference in the incidence of complications between the two groups(P>0.05).CONCLUSION: Silicone oil tamponade or C3F8 tamponade after PPV combined with ILM can both promote retinal reattachment and macular hole closure in patients with MHRD, and the C3F8 tamponade was superior to silicone oil in visual function recovery.

Accuracy of four formulas in predicting diopter of intraocular lens implanted in high myopia cataract eyes / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To evaluate the accuracy of the formulas, including Haigis, SRK/T, Holladay 1, and Holladay 2, in predicting the diopter of the intraocular lens implanted in high myopia cataract patients.METHODS: Prospective study. A total of 168 cases(168 eyes)of age-related cataract with an axial length(AL)≥26 mm who were treated in our hospital from August 2017 to November 2021 were selected. According to the preoperative AL measured by IOL Master 700, the patients were divided into five groups, including 37 cases(37 eyes)in group A with 26 mm≤AL<27 mm, 34 cases(34 eyes)in group B with 27 mm≤AL<28 mm, 42 cases(42 eyes)in group C with 28 mm≤AL<29 mm, 28 cases(28 eyes)in group D with 29 mm≤AL<30 mm, and 27 patients(27 eyes)in group E with AL ≥ 30 mm. Subjective refraction was performed at 3 mo postoperatively, and the mean numerical error(MNE)and mean absolute error(MAE)of each formula for predicting diopters were calculated.RESULTS: The MNE and MAE of the Haigis and Holladay 2 formulas were relatively less in each group, and MNE and MAE did not significantly increase with the growth of the axial length. However, the MAE and MNE of the SRK/T and Holladay 1 formulas significantly increased with the growth of the axial length, with the MNE and MAE of the Holladay 1 formula increasing more significantly in groups C, D, and E.CONCLUSION: For patients with age-related cataract, with an axial length of ≥26 mm, the accuracy of predicting the diopter of the intraocular lens using the Haigis and Holladay 2 formulas were higher.

Evaluation of early binocular visual function after implantable collamer lens V4c implantation in patients with high myopia / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To evaluate the binocular visual function in high myopia patients after the implantation of implantable collamer lens(ICL)V4c.METHODS: A total of 35 cases(70 eyes)that received binocular ICL implantation at our hospital from May 2019 to May 2021 were enrolled in this prospective study. Binocular full-range visual acuity, contrast sensitivity, stereopsis, mesopic vision and glare sensitivity, and monocular wavefront and the quality of vision questionnaire were assessed before the surgery and at 1 mo postoperatively.RESULTS: At 1 mo postoperatively, 35 cases(100%)had binocular uncorrected distance visual acuity(UDVA)≤0.00(LogMAR), 16 cases(46%)had binocular UDVA≥preoperative corrected distance visual acuity(CDVA). Binocular UDVA and uncorrected intermediate visual acuity(UIVA,80 cm)were improved compared to preoperative CDVA and distance-corrected intermediate visual acuity(DCIVA,80 cm)(all P<0.05).While there were no differences in the binocular postoperative UIVA(60 cm)and preoperative DCIVA(60 cm),and uncorrected near visual acuity(UNVA,40 cm)and preoperative distance-corrected near visual acuity(DCNVA,40 cm)(all P>0.05). The binocular contrast sensitivity was significantly improved postoperatively(P=0.001), and the postoperative binocular mesopic vision, glare sensitivity(no glare/glare)and binocular stereopsis(5 m/40 cm)had no differences(all P>0.05). The postoperative total higher-order aberration, trefoil aberration, coma and spherical aberration were increased, besides the median of total coma in the right eye with a pupil diameter of 3.0 mm was decreased after surgery. The mean total score of quality of vision questionnaire was significantly increased from 54.87 preoperatively to 80.92 after implantation(P<0.05), with high satisfaction and no obvious visual disturbance in patients.CONCLUSION: Although the monocular high-order aberrations increased in the early stage after ICL V4c binocular implantation in patients with high myopia, the binocular visual function was improved.

Comparison of IOL Master 700 versus Lenstar LS900 for preoperative biometric measurement and intraocular lens calculation in cataract patients with high myopia / 国际眼科杂志(Guoji Yanke Zazhi)

AIM:To compare the differences, correlations and consistency of IOL Master 700 or Lenstar LS900 in preoperative ocular biometry and the accuracy of intraocular lens(IOL)degree calculation of cataract patients with high myopia.METHODS: Retrospective study. A total of 136 cases(136 eyes)of high myopia and cataract patients who underwent phacoemulsification at the ophthalmology department of Army Medical Center of PLA from March 2021 to March 2023 were collected, with a mean age of 57.38±8.08 years. Patients were divided into 3 groups based on axial length(AL): 41 eyes in group A(26 mm≤ AL ≤28 mm), 43 eyes in group B(28 mm< AL ≤30 mm)and 52 eyes in group C(AL >30 mm). AL, mean keratometry(Km), anterior chamber depth(ACD), lens thickness(LT)and white-to-white(WTW)were preoperatively measured by two instruments, respectively. Barrett Universal II formula was used to calculate the IOL degrees of all patients, the appropriate reserved diopter was decided individually, and the prediction error(PE)and absolute error(AE)of the two instruments were compared.RESULTS:The AL and ACD of patients in the three groups measured by Lenstar LS900 were higher than the AL measurd by IOL Master 700(all P<0.05), with a difference of AL measured by the two devices: group C>group B>group A. However, there was no statistical significance in LT, Km, and WTW measured by the two instruments(all P>0.05). All biometric parameters measured by the two devices were positively correlated(all r>0.9, P<0.05), and consistent(95% LoA of all groups were narrow). There was no statistically significant difference in AE calculated by the two devices(P>0.05), but the IOL Master 700 calculated a smaller PE than Lenstar LS900(P<0.05), with lower percentage of hyperopic shift in IOL Master 700.CONCLUSION:In cataract patients with high myopia, AL measured by Lenstar LS900 is longer than that by IOL Master 700, and the differences of AL increase along with the growth of AL. Both devices have a good prediction for IOL calculation, but IOL Master 700 has less refractive error, lower percentage of hyperopic shift, and greater clinical advantages IOL Master 700.

Early outcomes of anterior segment parameters in patients with high myopia after implantable collamer lens V4c implantation / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To study the early outcomes of anterior segment parameters after implantation of an implantable collamer lens with a central hole(ICL V4c)in patients with high myopia.METHODS:A total of 82 cases(160 eyes)with high myopia, including 42 males(82 eyes)and 40 females(78 eyes), aged 26.0±4.6(21 to 37)years, who underwent ICL V4c implantation at our institution from February 2019 to September 2022 and were followed up for 1 a, were included. The general characteristics of the anterior segment of the eye were measured preoperatively: spherical equivalent, mean horizontal corneal curvature, white-to-white(WTW), and axial length(AL); intraocular pressure(IOP), endothelial cell density(ECD), central anterior chamber depth(CACD), anterior chamber volume(ACV)and anterior chamber angle(ACA)were measured preoperatively and at 1 d, 1 wk, 1, 3 and 6 mo postoperatively. Furthermore, the distance from the centre of the posterior surface of the ICL V4c optical zone to the anterior surface of the lens(vault)was measured at 1 d, 1 wk, 1, 6 mo, and 1 a after surgery.RESULTS: The mean preoperative spherical equivalent of the patients was -7.56±2.55 D, mean horizontal corneal curvature was 42.89±1.47 D, WTW was 11.64±0.37 mm, and AL was 26.64±0.93 mm. The baseline IOP was 15.97±2.13 mmHg, and the differences in IOP at each time point after ICL V4c implantation compared to preoperative were not statistically significant(F=0.875, P=0.504); ECD was 2 989.30±140.78 cells/mm2 at baseline, and ECD at 6 mo after ICL V4c implantation was not statistically significant compared with preoperative ECD(t=1.475, P=0.142); CACD was 3.19±0.21 mm at baseline, and ACV was 210.30±27.7 mm3, and CACD and ACV were significantly lower than preoperative at all postoperative time points(F=111.10, 288.38, all P<0.001). The baseline ACA was 35.44°±11.27°, and the ACA at each time point after ICL V4c implantation was significantly lower than preoperatively(F=21.23, P<0.001). The vault was 665.32±184.03 μm at 1 d postoperatively, and continued to be significantly reduced at 1 wk, 1, 6 mo, and 1 a postoperatively compared with 1 d(F=52.10, P<0.001). However, it remained stable at 6 mo and 1 a postoperatively, and the difference was not statistically significant compared with vault at 1 mo postoperatively(P>0.05).CONCLUSION: ICL V4c has certain safety and efficiency in 1 a postoperative follow-up, and the parameters of the anterior segment of the eye stabilized in the early period.

Phacoemulsification combined with capsular tension ring and intraocular lens implantation in the treatment of high myopia with cataract / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To observe the efficacy of phacoemulsification combined with capsular tension ring and intraocular lens implantation in the treatment of high myopia with cataract.METHODS: Retrospective study. A total of 82 cases(82 eyes)of high myopia complicated with cataract who admitted to the cataract department of our hospital from December 2021 to April 2023 were selected as study objects, and they were divided into control group(n=39)and combination group(n=43)according to whether or not the capsular tension ring was used intraoperatively. Patients in the control group were treated with intraocular lens implantation alone, and those in the combination group were treated with phacoemulsification combined with capsular tension ring and intraocular lens implantation. The preoperative and postoperative best corrected visual acuity, central anterior chamber depth, trabecular ciliary process, visual quality and complications were compared.RESULTS: At 1 mo after surgery, the best corrected visual acuity(LogMAR)of both groups increased significantly(combination group: 0.64±0.28 vs 0.12±0.14; control group: 0.62±0.26 vs 0.23±0.25, both P<0.001). Central anterior chamber depth in both groups were higher than those before surgery(combination group: 2.57±0.56 vs 1.97±0.40 mm; control group: 2.22±0.45 vs 1.89±0.37 mm; both P<0.001), and the best corrected visual acuity and central anterior chamber depth of the combination group were significantly better than those of the control group(both P<0.05). The distance of trabecular ciliary process showed no statistical significance(combination group: 0.68±0.22 vs 0.74±0.20 mm; control group: 0.74±0.19 vs 0.78±0.17 mm, both P>0.05). The visual quality scores of the combination group were all higher than the control group at 1 mo after surgery [watching TV: 3.00±0.38 vs 2.22±0.46 points; reading books: 2.85±0.42 vs 2.21±0.44 points; night vision: 2.71±0.34 vs 2.37±0.41 points; fine operation: 2.82±0.38 vs 2.33±0.40 points, all P<0.001]. The incidence of complication in the combination group was significantly lower than that of the control group(33% vs 14%, P<0.05).CONCLUSION: Phacoemulsification combined with capsular tension ring and intraocular lens implantation can effectively promote the recovery of visual function, improve the structure of chamber angle, and reduce the incidence of complications in the treatment of patients with high myopia and cataract.

Research progress of long-term efficacy after implantation of implantable collamer lens V4c / 国际眼科杂志(Guoji Yanke Zazhi)

With the rapid development of science and technology and the wide application of electronic products, the number of patients with high myopia is gradually increasing. Meanwhile, owing to the continuous optimization of surgical skils and the continuous advancement in materials of posterior chamber intraocular lens and manufacturing processes, implantable collamer lens(ICL)V4c implantation has gradually become one of the main surgeries for the treatment of high myopia. In the rapid era of social information, people pay more attention to the long-term efficacy after ICL V4c implantation, they not only want clear vision, but also the pursuit of visual comfort and durability. Therefore, this paper will specifically discuss the research progress of the post-implantation efficacy of ICL V4c with at least 2 a of follow-up observation within 3 a, aiming to review the latest research progress on the long-term efficacy of ICL V4c implantation from the three dimensions of visual quality, safety, efficacy and stability and possible surgical complications after ICL V4c implantation.

Research progress on morphology of macular foveal avascular zone in ocular diseases based on optical coherence tomography angiography measurement / 国际眼科杂志(Guoji Yanke Zazhi)

The foveal avascular zone(FAZ)is the most sensitive region of the retina, which is interconnected by the macular capillary plexus. Its morphology can indirectly reflect the alterations of macular microcirculation. With strong repeatability and reliability, optical coherence tomography angiography(OCTA)can non-invasively visualize and quantify the FAZ. The great value of OCTA makes it an important supplemental examination tool in ophthalmology and other professions. The area and perimeter of FAZ have been demonstrated to be an effective clinical diagnostic indicator in high myopia, diabetic retinopathy, glaucoma and other ocular diseases. In recent years, the geometry of FAZ has also proven to have clinical value. The parameters describing the geometry of FAZ, such as circularity index, acircularity index and axial ratio, provide a new perspective for ocular disease research. The comprehensive investigation of the morphological characteristics of the FAZ is helpful to explore the pathological mechanism of the occurrence and development of ocular diseases, predict preclinical changes, make pathological stages of the disease precise, and provide a theoretical basis for monitoring the disease's progression and assessing patients' visual prognosis.

Novel mutation in SCO2 of patients with high myopia from Enshi Tujia and Miao Autonomous Prefecture of China / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To evaluate the pathogenic variants of the SCO2(OMIM 604272)gene in patients with high myopia from Enshi Tujia and Miao Autonomous Prefecture of China.METHODS: A total of 384 patients with high myopia whose spherical refractive error was ≤ -6.00 D and whose axial length was ≥26.00 mm in at least one eye were recruited. DNA was extracted by the phenol-chloroform method from 5 mL of peripheral venous blood. Sanger sequencing was performed to identify pathogenic variants in exon 2 of SCO2. The detected variants were evaluated via in silico prediction software. A total of 288 people from the same district were included as the normal control cohort.RESULTS: Seven variants were detected, namely, four synonymous variants(c.201C>T/p.=, c.576C>T/p.=, c.633A>C/p.=, c.780T>C/p.=.), two missense variants(c.187A>G/p.Ile63Val, c.59G>C/p.Arg20Pro)and one nonsense variant(c.544C>T/p.Gln182*). The two missense variants were not damaging, as predicted by PolyPhen2, SIFT and Provean. The novel nonsense variant(c.544C>T/p.Gln182*)cannot be found in the 1000 Genomes Project and was not identified in 288 normal controls. Variant Taster suggested that the nonsense variant site was conserved.CONCLUSION: The newly identified nonsense mutation may be responsible for high myopia of the patients in our cohort. SCO2 is associated with high myopia, while the incidence of SCO2 variants in high myopia in this cohort was as low as 1/384; the nonsense mutation may be a scarce variant of high myopia in the Enshi Tujia and Miao Autonomous Prefecture of China.

Observation on the efficacy of moderate and high myopia patients with vault greater than 1 000 μm after implantation of phakic posterior chamber implantable contact lens / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To observe the efficacy of moderate and high myopia patients with vault greater than 1 000μm after implantation of phakic posterior chamber implantable contact lens(ICL).METHODS: A total of 42 patients(73 eyes)who received ICL implantation in the hospital and had postoperative vault greater than 1 000 μm between January 2014 and January 2017 were selected and retrospectively studied. Changes in visual acuity, intraocular pressure, corneal endothelial cell density, anterior chamber-related parameters(chamber angle, central anterior chamber depth, anterior chamber volume)and vault were compared among patients before surgery, at 1, 3, 6mo and 1a after surgery and at the last follow-up.RESULTS: The uncorrected visual acuity(UCVA)at 1, 3, 6mo and 1a after surgery and at the last follow-up was better than that before surgery(all P<0.05), and the chamber angle, central anterior chamber depth and anterior chamber volume were smaller or lower than those before surgery(all P<0.05), but there were no statistical differences in UCVA, chamber angle, central anterior chamber depth and anterior chamber volume at each time point after surgery(all P>0.05). The intraocular pressure at 1mo after surgery was lower than that before surgery(P<0.05), but the intraocular pressure at 3, 6mo and 1a after surgery and at the last follow-up was not statistically different from that before surgery(all P>0.05). There was no statistical significance in the corneal endothelial cell density at 1, 3, 6mo and 1a after surgery and at the last follow-up compared with that before surgery(all P>0.05). The vault at 1, 3, 6mo and 1a after surgery and at the last follow-up showed a decreasing trend, and the difference was statistically significant at each time point after surgery(all P<0.05).CONCLUSION: The short-term and long-term efficacy are better in moderate and high myopia patients with vault greater than 1 000 μm after ICL implantation, and there are no significant effects on the intraocular pressure and corneal endothelial cell. The postoperative anterior chamber structure is relatively stable and the vault tends to decrease over time. In most cases, close observation is sufficient and intraocular lens replacement is generally not required.

Femtosecond laser-assisted cataract phacoemulsification combined with Toric intraocular lenses implantation in correction of high myopia cataract and corneal astigmatism / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To measure the indexes including postoperative distance, middle, near visual acuity and near stereopsis vision of patients with high myopia cataract and corneal astigmatism by femtosecond laser, which can quantify the diameter of capsulorhexis opening, and to evaluate the availability and necessity of Toric intraocular lenses(IOL)in high myopia.METHODS: Prospective case-control study. Patients with binocular high myopia cataract and corneal astigmatism who undergone femtosecond laser-assisted cataract surgery in our hospital were selected, and they were divided into two groups, with 20 cases(40 eyes)in group A(Toric IOL)and 20 cases(40 eyes)in group B(IQ IOL). Indexes, including preoperative corneal astigmatism and spherical equivalent and best-corrected distance visual acuity, uncorrected middle visual acuity, uncorrected near visual acuity, residual refractive astigmatism, near stereopsis acuity, total high-order aberration and total spherical aberration, were measured postoperatively at 7d, 1 and 3mo.RESULTS: The uncorrected middle and near visual acuity, Titmus near stereopsis acuity and residual astigmatism at 7d, 1 and 3mo after surgery were significantly improved in the Toric IOL group than the non-Toric group(all P<0.05). The dependence on glasses was reduced. The postoperative best-corrected distance visual acuity, total high-order aberration and total spherical aberration of the two groups showed no statistically significant differences(all P>0.05).CONCLUSIONS: The implantation of Toric IOL in patients with high myopia cataract and corneal astigmatism can effectively correct corneal astigmatism, improve postoperative uncorrected middle and near visual acuity and near stereopsis visual function, reduce postoperative dependence on glasses and enhance binocular stereopsis visual function.

Analysis of refractive error factors in patients with high myopia combined with cataract after different operation / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To investigate the changes in anterior chamber depth(ACD), axial length(AL), and corneal curvature(K)after operation in patients with high axial myopia combined with cataract, and the effect on postoperative mean refractive error(MFE)by different surgical approaches.METHODS: A total of 126 patients(126 eyes)performed cataract combined with intraocular lens(IOL)implantation were selected and divided into 3 groups according to different surgical approaches and axial length. Group A included 42 patients(42 eyes)who had cataract combined with high myopia and were performed cataract phacoemulsification combined with IOL implantation; Group B included 42 patients(42 eyes)who had cataract combined with high myopia and underwent small incision cataract extracapsular extraction combined with IOL implantation; Group C included 42 patients(42 eyes)who had cataract with normal axial length and underwent cataract phacoemulsification combined with IOL implantation. Then, the ACD, AL, K value and visual acuity of the three groups at 1d before operation and 3mo after operation were measured, and statistical analysis was performed.RESULTS: The differences in the mean values of preoperative and postoperative changes in ACD(△ACD)and AL(△AL)between groups A and B showed no statistical significance. The differences in the mean values of △ACD and △AL between groups A and C and groups B and C were both statistically significant(both P<0.01). △ACD and △AL in all three groups showed positive correlation(rA=0.855, rB=0.856, rC=0.639, all P<0.05). Furthermore, preoperative AL, △AL, △ACD and MFE in all three groups showed positive correlation(rA=0.874, 0.877, 0.858, rB=0.875, 0.879, 0.858, rC=0.428, 0.766, 0.862, all P<0.05). The standardized regression coefficients of groups A and B were △AL>△ACD(1.32 and 1.31 times), and the standardized regression coefficients of group C were △ACD>△AL(1.66 times).CONCLUSION: Different surgical procedures had no significant effect on the postoperative K value and MFE in patients with high axial myopia combined with cataract, of which main influencing factor is the change in the AL before and after surgery. The postoperative MFE in patients with normal AL was more due to the change of ACD.

Research progress of fundus morphology in high myopia / 国际眼科杂志(Guoji Yanke Zazhi)

High myopia is the main cause of visual impairment in the world. With the development of society, the myopia rate is increasing year by year. The development of high myopia is closely related to the progressive extension of the eye axis, and a series of fundus changes will inevitably occur with the extension of the eye axis, such as comus, lacquer cracks, choroidal neovascularization, macular choroidal atrophy, retinal detachment, posterior scleral staphyloma, etc. At present, characterized by younger age and high degree, myopia has become the main cause of blindness in China. This paper briefly summarizes the latest research on the morphological changes of the optic disc, macula, retina, choroid and sclera of high myopia, aiming to provide references for the development of intelligent prediction models, clinical diagnosis and further research on the treatment measures in combination with the fundus morphology of high myopia.

Accuracy of Wang-Koch axial length adjustment formulas in calculating postoperative refractive power in cataract patients with high myopia / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To compare the accuracy between Wang-Koch axial length adjustment formulas(SRK/TWK, Holladay ⅠWK)and SRK/T, Haigis, Holladay Ⅰ, Hoffer Q in calculating intraocular lens power of cataract patients with high myopia.METHODS: A total of 42 cataract patients with high myopia(57 eyes)were collected. All eyes underwent phacoemulsification combined with intraocular lens implantation surgery in our Hospital from September 2019 to March 2022. They were divided into two groups according to the axial length(AL): group A(27mm≤AL<30mm, 31 eyes)and group B(AL≥30mm, 26 eyes). Patients were followed up at 3mo. The actual postoperative diopter was recorded, and then the refractive mean numerical error(MNE)and mean absolute error(MAE)were calculated.RESULTS: MAE of each formulas was statistically different after surgery(P<0.01), among which the MAE of Holladay ⅠWK and SRK/TWK [0.31(0.08, 0.57), 0.34(0.17, 0.63)D] was lower than other formulas. However, there were no statistical difference between SRK/TWK, Holladay ⅠWK and SRK/T, Haigis formulas [0.61(0.27, 1.02), 0.63(0.22, 1.01)D](P>0.05). MAE were statistically different among the formulas in group A(27mm≤AL<30mm; P<0.01). The MAE of Holladay ⅠWK and SRK/TWK was lower than other formulas [0.18(0.05, 0.51), 0.28(0.16, 0.52)D], but there were no statistical difference with SRK/T and Haigis formulas [0.45(0.18, 0.65), 0.50(0.14, 0.75)D](P>0.05). In group B(AL≥30mm), the MAE of each formulas was statistically different after surgery(P<0.01), among which MAE of Holladay IWK and SRK/TWK was the lowest, followed by SRK/T and Haigis, whereas, Holladay I and Hoffer Q ranked the highest. Furthermore, there were statistical differences between MAE of SRK/TWK, Holladay ⅠWK [0.44(0.23, 0.67), 0.41(0.22, 0.66)D] and SRK/T, Haigis formulas [0.78(0.55, 1.07), 0.75(0.45, 1.25)D](all P<0.05).CONCLUSION: For cataract patients with AL ≥30mm, the Wang-Koch axial length adjustment formulas were relatively accurate in calculating diopter of intraocular lens, and had clinical application value to some extent.

Progress on the application of capsular tension ring in high myopia combined with cataract / 国际眼科杂志(Guoji Yanke Zazhi)

In recent years, the incidence of high myopia complicated with cataract shows a gradual upward trend. Due to the special anatomical structure and lesion nature of high myopia, the difficulty and various complications of such patients are much higher than those of ordinary cataract surgery. With the continuous advancement of design and materials, the indications for capsular tension ring(CTR)have gradually expanded. Especially for patients with high myopia,it can maintain the stability of intraocular lens position, assist the relaxation of the suspensory ligament, inhibit the migration and proliferation of residual lens epithelial cells after surgery, improve the visual quality of patients and reduce the incidence of retinal detachment. This paper reviewed the history of CTR, its clinical application, and the effect of CTR on high myopia complicated with cataract.

Analysis of the influencing factors of vault after the implantation of posterior chamber-phakic refractive lens for patients with super high myopia / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To investigate the influencing factors of vault after the posterior chamber phakic refractive lens(PC-PRL)implantation for patients with super high myopia.METHODS: Retrospective case study. A total of 40 patients with super high myopia(77 eyes)who underwent PC-PRL implantation in the Haixiang Eye Hospital from January 2019 to January 2021 were selected. They were followed up for at least 2a, postoperative anterior segment parameters, such as the uncorrected visual acuity(UCVA), best corrected visual acuity(BCVA), central anterior chamber depth(ACD), anterior chamber volume(ACV), anterior chamber angle(ACA), lens thickness and vault were evaluated, and then the influencing factors of postoperative vault were analyzed.RESULTS: The UCVA and BCVA of the patients significantly improved after PC-PRL implantation(P<0.001). Average safety index(postoperative BCVA/preoperative BCVA)was 1.36±0.32, and average effective index(postoperative UCVA/preoperative BCVA)was 1.23±0.31 in 2a after surgery. The vault in 2a after surgery was correlated with preoperative ACD, ACV, ACA and lens thickness, and the preoperative ACV and lens thickness had significant impact on vault in 2a after surgery.CONCLUSIONS: The PC-PRL implantation is safe and effective in super high myopia, and it can significantly improve visual acuity. Furthermore, preoperative ACV and lens thickness are important influencing factors of postoperative vault.

Efficacy comparison between rigid and foldable anterior iris-fixated phakic intraocular lens implantation for treating high myopia in Asian eyes / 国际眼科杂志(Guoji Yanke Zazhi)

AIM:To compare refractive and safety outcome of Artisan and Artiflex phakic intraocular lens(PIOL)for the correction of high myopia in Asian population.METHODS:Historical cohort study. A total of 81 high myopic eyes that underwent PIOL implantation from 2016 to 2020 at Yap Eye Hospital in Yogyakarta, Indonesia were reviewed. The patients were divided into two groups based on PIOL implanted, with 43 eyes using Artisan PIOL in Artisan group and 38 eyes using Artiflex PIOL in Artiflex group. Visual acuity, corneal biomicroscopy parameters, and intraocular pressure(IOP)were respectively recorded prior to the implantation and at 1d, 1 and 3mo after surgery. In addition, anterior chamber depth was documented before PIOL implantation.RESULTS:Mean follow-up period were 9.64±6.93mo and 8.96±4.28mo in Artisan an Artiflex group, respectively(P=0.736). The efficacy index was 1.03±0.47 in Artisan group, and 1.02±0.17 in the Artiflex group(P=0.119).The safety index was 1.10±0.45 and 1.05±0.21 in Artisan and Artiflex group, respectively(P<0.001). The mean spherical equivalent(SE)in Artisan group was -0.64±0.996D, and it was -0.22±0.58D in Artiflex group(P=0.076). In both groups, there was a significant loss of endothelial cell density(ECD)postoperatively compare to baseline(P<0.05), and the cumulative ECD loss was 7.44% and 5.79% in the Artisan and Artiflex groups, respectively(P=0.418).CONCLUSION:Artisan and Artiflex are comparable in terms of refractive outcome to correct high myopia in Asian eyes. Artisan had a slightly better safety index compare to Artiflex. However, the efficacy index and cumulative ECD loss was similar in both the Artisan and Artiflex groups.

Comparison of accuracy of intraocular lens calculation formulas in cataract eyes with prior radial keratotomy and axial length longer than 28mm / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To compare the accuracy of different intraocular lens(IOL)calculation formulas in cataract patients with axial length longer than 28mm and a history of radial keratotomy(RK).METHODS: Retrospective study. The medical records of 19 cataract patients(29 eyes)after RK and with axial length longer than 28mm who underwent cataract surgery from January 2011 to July 2020 in Beijing Tongren Hospital were analyzed. The absolute error(AE)of the difference among three different formulas was calculated. AE refers to the absolute value between the actual spherical equivalent after cataract surgery and the spherical equivalent predicted by the IOL formula. The AE values of the three formulas and the percentages of eyes with AE≤0.5, 0.75, 1.0, and 2.0D were calculated and compared.RESULTS: The AE values of the three formulas were significantly different(χ2=8.759, P=0.013). The Barrett True-K formula had the smallest median AE, which was only 0.62(0.20, 1.15)D, followed by the Haigis formula 0.76(0.34, 1.26)D, and the Holladay 1(D-K)formula had the largest 1.01(0.49, 1.62)D. The percentages of affected eyes with AE ≤0.5, 0.75, 1.0, and 2.0D for the Barrett True-K formula were 48%, 59%, 69%, and 93%, which were equal to or higher than the other two formulas.CONCLUSION: The Barrett True-K formula is more recommended among the three formulas for cataract patients after RK and with axial length longer than 28 mm.

Curative effect of full-femtosecond small incision lenticule extraction on the treatment of high myopia based on propensity score matching / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To analyze the effect of full-femtosecond small incision lenticule extraction(SMILE)on the treatment of high myopia based on propensity score matching.METHODS: A total of 48 cases(48 eyes)of high myopia patients who underwent SMILE surgery in our hospital from May 2019 to May 2021 were selected as the observation group, and 48 cases(48 eyes)of high myopia patients who underwent FS-LASIK surgery were matched using propensity score matching as the control group. Follow up for 6mo after surgery, the changes in cylindrical, central corneal thickness, uncorrected visual acuity(UCVA), corneal endothelial cell related indicators [percentage of hexagonal endothelial cells(6A), coefficient of variation(CV)of endothelial cell area, central corneal endothelial cell density(ECD)] and corneal biomechanical indicators [simulated Goldman intraocular pressure(IOPg), corneal hysteresis(CH), corneal resistance factor(CRF), corneal compensated intraocular pressure(IOPcc)] between the two groups were compared, and the incidence of complications in both groups of patients was recorded.RESULTS: Both groups of patients showed significant improvements in cylindrical and UCVA at 3 and 6mo after surgery, as well as decreased central corneal thickness, corneal endothelial cells, and corneal biomechanics related indicators. The changes in the observation group were more significant(all P<0.05). During the follow-up period, there was no significant difference in the incidence of complications between the observation group and the control group(8% vs. 17%, P>0.05).CONCLUSION: SMILE has a definite effect on patients with high myopia and is helpful to improve visual acuity.

Efficacy of implantable collamer lens V4c implantation in the treatment of high myopia / 国际眼科杂志(Guoji Yanke Zazhi)

AIM:To observe the effect of implantable collamer lens V4c(ICL V4c)implantation on high myopia, and the changes in anterior segment morphology.METHODS:A prospective study was conducted on 100 patients(200 eyes)with high myopia who were treated with ICL V4c implantation in the hospital from February 2018 to March 2021. The best corrected visual acuity(BCVA), uncorrected visual acuity(UCVA), intraocular pressure, higher-order aberration, anterior segment morphology [iridocorneal angle(ICA), central anterior chamber depth(ACD), anterior chamber volume(ACV), central corneal thickness(CCT)and K-value(K)], photopic and scotopic contrast sensitivity before operation and 6 and 12mo after operation were comparatively analyzed.RESULTS:All patients were followed-up. UCVA and BCVA were significantly improved at 6 and 12mo after operation(P<0.05). Total higher-order aberration, horizontal coma and vertical coma showed no significant difference before and after operation(P>0.05). Spherical aberration, ICA, ACD and ACV at 6 and 12mo after operation were significantly smaller than those before operation(P<0.05). Under photopic state, the contrast sensitivity of 3.0 and 6.0 c/d was significantly higher at 6 and 12mo after operation when compared with that before operation(P<0.05). Under scotopic state, the contrast sensitivity of 6.0 c/d was significantly higher at 6 and 12mo after operation when compared with that before operation(P<0.05); there was no significant difference in CCT, K, or intraocular pressure before and after operation(P>0.05).CONCLUSION:Although ICA, ACD and ACV in patients with high myopia are reduced after ICL V4c implantation, the operation can effectively improve visual acuity and visual quality.