1.Advances in the application of adaptive optics visual simulators in refractive surgery
Yan WANG ; Xuan LIAO ; Changjun LAN
International Eye Science 2025;25(10):1645-1649
Adaptive optics(AO)is a technology designed to enhance the performance of optical systems through real-time measurement and correction of optical aberrations. With continuous advancements in refractive surgery techniques and rising patient expectations for surgical outcomes, the precise implementation of personalized refractive corrections has become a critical focus. The integration of AO technology into refractive surgery provides novel technical support. Specifically, the adaptive optics vision simulator(VAO)facilitates accurate preoperative objective and subjective refraction by dynamically measuring and correcting ocular wavefront aberrations, thereby improving refractive efficiency. Additionally, it enables effective prediction of postoperative aberrations for personalized procedures, assists clinicians in making data-driven preoperative decisions, facilitates comparative analysis of different surgical techniques, and allows intuitive evaluation of postoperative visual quality. This review comprehensively examines the advances in VAO applications for refractive surgery and analyzes both its clinical advantages and technical limitations.
2.Research progress on age-related changes in binocular vision
Chunyan LAI ; Changkang LUO ; Xuan LIAO ; Changjun LAN ; Qingqing TAN
International Eye Science 2025;25(11):1820-1825
With the accelerating process of population aging, binocular vision disorders have become increasingly prevalent, posing new challenges for both social aging strategies and ophthalmic clinical practice. Non-strabismic binocular vision anomalies(NSBVAs)are notably prevalent among elderly populations; however, current research predominantly focuses on the abnormality rates derived from individual binocular vision clinical tests, while data on the actual prevalence based on comprehensive diagnostic criteria remain limited. This review synthesizes existing scientific literature to provide a concise yet comprehensive overview of the prevalence, risk factors, and clinical diagnostic methods of NSBVAs in pre-presbyopic and presbyopic populations, with an in-depth examination of age-related changes in binocular vision function among older adults. By integrating and comparing analyses of the correlations between age and various binocular vision parameters, this review aims to enhance understanding of age-related binocular vision dysfunction and establish a theoretical foundation for developing targeted diagnostic and therapeutic approaches. Ultimately, these insights could contribute to improved visual performance and life satisfaction in elderly individuals.
3.One-year clinical observation of epithelial-off accelerated corneal collagen cross-linking on the treatment of progressive keratoconus
Jing LU ; Ping MA ; Changjun LAN
International Eye Science 2025;25(3):451-454
AIM: To assess the clinical efficacy and safety of epithelial-off accelerated corneal collagen cross-linking(CXL)in the management of progressive keratoconus over 1 a period.METHODS:A retrospective pre-post self-controlled study. Data were collected from complete cases of 63 patients(84 eyes)with progressive keratoconus who underwent epithelial-off accelerated CXL between August 2018 and September 2021. Uncorrected visual acuity(UCVA), best corrected visual acuity(BCVA), refraction, corneal transparency, maximum keratometry(Kmax)of the anterior corneal surface, minimum corneal thickness, endothelial cell counts, and intraocular pressure(IOP)were analyzed preoperatively and at 1, 3, 6, and 12 mo postoperatively.RESULTS:No significant differences were observed in UCVA and spherical power before and after surgery(all P>0.05). However, there were significant differences in BCVA, cylinder power, Kmax, minimum corneal thickness, and IOP(all P<0.05). At 12 mo postoperatively, there were no significant differences in BCVA, cylinder power, minimum corneal thickness, and IOP compared with preoperative values(all P>0.05), while Kmax was decreased compared with preoperative value(P<0.05). At 1 mo postoperatively, the corneal endothelial cell count(2519.87±345.28 cells/mm2)was decreased compared with preoperative value(2693.63±313.39 cells/mm2; P<0.001). At 1 wk postoperatively, 22 eyes developed corneal haze(grade 0.5 to 1), and 15 eyes presented with linear corneal stromal opacity at 1 mo postoperatively. In 7 eyes, corneal opacity subsided within 3 to 6 mo after the operation, however, 5 eyes still exhibited corneal nebula or macula without affecting visual acuity.CONCLUSION: After epithelial-off accelerated CXL, the UCVA, BCVA and spherical diopter of patients remained stable over time. The astigmatism and corneal curvature temporarily increased and then gradually decreased. The cornea minimum thickness decreased initially but subsequently returned to preoperative levels. The corneal curvature at 6 and 12 mo after surgery was significantly lower than that before surgery, which could effectively prevent the progression of keratoconus. Despite potential localized corneal opacity and macular complications, as well as a possible decrease in corneal endothelial cell count, BCVA remained unaffected, demonstrating favorable safety outcomes.
4.One-year clinical observation of epithelial-off accelerated corneal collagen cross-linking on the treatment of progressive keratoconus
Jing LU ; Ping MA ; Changjun LAN
International Eye Science 2025;25(3):451-454
AIM: To assess the clinical efficacy and safety of epithelial-off accelerated corneal collagen cross-linking(CXL)in the management of progressive keratoconus over 1 a period.METHODS:A retrospective pre-post self-controlled study. Data were collected from complete cases of 63 patients(84 eyes)with progressive keratoconus who underwent epithelial-off accelerated CXL between August 2018 and September 2021. Uncorrected visual acuity(UCVA), best corrected visual acuity(BCVA), refraction, corneal transparency, maximum keratometry(Kmax)of the anterior corneal surface, minimum corneal thickness, endothelial cell counts, and intraocular pressure(IOP)were analyzed preoperatively and at 1, 3, 6, and 12 mo postoperatively.RESULTS:No significant differences were observed in UCVA and spherical power before and after surgery(all P>0.05). However, there were significant differences in BCVA, cylinder power, Kmax, minimum corneal thickness, and IOP(all P<0.05). At 12 mo postoperatively, there were no significant differences in BCVA, cylinder power, minimum corneal thickness, and IOP compared with preoperative values(all P>0.05), while Kmax was decreased compared with preoperative value(P<0.05). At 1 mo postoperatively, the corneal endothelial cell count(2519.87±345.28 cells/mm2)was decreased compared with preoperative value(2693.63±313.39 cells/mm2; P<0.001). At 1 wk postoperatively, 22 eyes developed corneal haze(grade 0.5 to 1), and 15 eyes presented with linear corneal stromal opacity at 1 mo postoperatively. In 7 eyes, corneal opacity subsided within 3 to 6 mo after the operation, however, 5 eyes still exhibited corneal nebula or macula without affecting visual acuity.CONCLUSION: After epithelial-off accelerated CXL, the UCVA, BCVA and spherical diopter of patients remained stable over time. The astigmatism and corneal curvature temporarily increased and then gradually decreased. The cornea minimum thickness decreased initially but subsequently returned to preoperative levels. The corneal curvature at 6 and 12 mo after surgery was significantly lower than that before surgery, which could effectively prevent the progression of keratoconus. Despite potential localized corneal opacity and macular complications, as well as a possible decrease in corneal endothelial cell count, BCVA remained unaffected, demonstrating favorable safety outcomes.
5.Effect of decentration and tilt on in vitro optical quality of intraocular lenses with different focus designs
Ruolin PAN ; Xuan LIAO ; Changjun LAN ; Lixuan XIE ; Qingqing TAN ; Suyun QIN ; Huan HUANG ; Yan WANG
Chinese Journal of Experimental Ophthalmology 2025;43(3):211-218
Objective:To observe the effect of different degrees of decentration and tilt on the optical quality of the intraocular lenses (IOLs) with different focus designs.Methods:The UV 3300 PC UV-visible spectrophotometer was employed to measure the spectral transmittance of the monofocal IOL CT ASPHINA 509M (509M), bifocal IOL AT LISA 809M (809M), and trifocal IOL AT LISA Tri 839MP (839MP) within Zeiss MICS platform with a refractive power of + 20 D. The modulation transfer function (MTF) values at a spatial frequency of 50 lp/mm along with MTF curves and United States Air Force (USAF) resolution test charts for each IOL at the focal point were measured at apertures of 3.0 mm and 4.5 mm using the in vitro optical quality testing system OptiSpheric IOL R&D under centered, decentered (0.3, 0.5, 0.7, 0.9 and 1.1 mm) and tilted (3°, 5°, 7°, 9° and 11°) conditions. Results:All three IOLs filtrated the ultraviolet (UV) spectrum below 400 nm.When each IOL was in the centered position, at the 3.0 mm aperture, the MTF values were 0.772 at the far focus of the monofocal IOL 509M, 0.467 and 0.282 at the far and near focus of the bifocal IOL 809M, and 0.416, 0.147, and 0.229 at the far, intermediate, and near focus of the trifocal IOL 839MP, respectively.Whereas at the 4.5 mm aperture, the monofocal IOL 509M MTF value at the far focus was 0.664, the bifocal IOL 809M MTF values at the far and near focus were 0.506 and 0.264, and the trifocal IOL 839MP MTF values at the far, intermediate, and near focus were 0.392, 0.107, and 0.210, respectively.Among the three centered IOLs, the 509M demonstrated the highest MTF value at the far focus, followed by the 809M and then the 839MP; at the near focus, the MTF value of the 809M surpassed that of the 839MP.For decentration and tilt, the difference in MTF values of the three IOLs at the far and near focus was consistent with the differences observed when they were centered.At the same degree of decentration and tilt, all three IOLs exhibited superior optical quality at the 3.0 mm aperture compared to the 4.5 mm aperture.The optical quality of all three IOLs exhibited an overall decline as decentration and tilt increased.All three IOLs demonstrated a decrease in optical quality at the decentration of 0.3 mm or the tilt of 5°.Conclusions:The IOLs within the Zeiss MICS platform design exhibits identical spectral transmittance and UV filtering properties.Among the three IOLs, when centered, the 509M, the 839MP, and the 809M exhibit superior optical quality at the far, intermediate, and near focal points, respectively.Under decentered and tilted conditions, the 509M and the 809M demonstrate better resistance against decentration and tilt, respectively, at both far and near focuses.Additionally, all three IOLs demonstrate better optical quality at smaller apertures, given equivalent degrees of decentration or tilt.However, the optical quality at each focal point of the three IOLs decreases compared to the centered position when subjected to a decentration of 0.3 mm or a tilt of 5°.
6.Effect of decentration and tilt on in vitro optical quality of intraocular lenses with different focus designs
Ruolin PAN ; Xuan LIAO ; Changjun LAN ; Lixuan XIE ; Qingqing TAN ; Suyun QIN ; Huan HUANG ; Yan WANG
Chinese Journal of Experimental Ophthalmology 2025;43(3):211-218
Objective:To observe the effect of different degrees of decentration and tilt on the optical quality of the intraocular lenses (IOLs) with different focus designs.Methods:The UV 3300 PC UV-visible spectrophotometer was employed to measure the spectral transmittance of the monofocal IOL CT ASPHINA 509M (509M), bifocal IOL AT LISA 809M (809M), and trifocal IOL AT LISA Tri 839MP (839MP) within Zeiss MICS platform with a refractive power of + 20 D. The modulation transfer function (MTF) values at a spatial frequency of 50 lp/mm along with MTF curves and United States Air Force (USAF) resolution test charts for each IOL at the focal point were measured at apertures of 3.0 mm and 4.5 mm using the in vitro optical quality testing system OptiSpheric IOL R&D under centered, decentered (0.3, 0.5, 0.7, 0.9 and 1.1 mm) and tilted (3°, 5°, 7°, 9° and 11°) conditions. Results:All three IOLs filtrated the ultraviolet (UV) spectrum below 400 nm.When each IOL was in the centered position, at the 3.0 mm aperture, the MTF values were 0.772 at the far focus of the monofocal IOL 509M, 0.467 and 0.282 at the far and near focus of the bifocal IOL 809M, and 0.416, 0.147, and 0.229 at the far, intermediate, and near focus of the trifocal IOL 839MP, respectively.Whereas at the 4.5 mm aperture, the monofocal IOL 509M MTF value at the far focus was 0.664, the bifocal IOL 809M MTF values at the far and near focus were 0.506 and 0.264, and the trifocal IOL 839MP MTF values at the far, intermediate, and near focus were 0.392, 0.107, and 0.210, respectively.Among the three centered IOLs, the 509M demonstrated the highest MTF value at the far focus, followed by the 809M and then the 839MP; at the near focus, the MTF value of the 809M surpassed that of the 839MP.For decentration and tilt, the difference in MTF values of the three IOLs at the far and near focus was consistent with the differences observed when they were centered.At the same degree of decentration and tilt, all three IOLs exhibited superior optical quality at the 3.0 mm aperture compared to the 4.5 mm aperture.The optical quality of all three IOLs exhibited an overall decline as decentration and tilt increased.All three IOLs demonstrated a decrease in optical quality at the decentration of 0.3 mm or the tilt of 5°.Conclusions:The IOLs within the Zeiss MICS platform design exhibits identical spectral transmittance and UV filtering properties.Among the three IOLs, when centered, the 509M, the 839MP, and the 809M exhibit superior optical quality at the far, intermediate, and near focal points, respectively.Under decentered and tilted conditions, the 509M and the 809M demonstrate better resistance against decentration and tilt, respectively, at both far and near focuses.Additionally, all three IOLs demonstrate better optical quality at smaller apertures, given equivalent degrees of decentration or tilt.However, the optical quality at each focal point of the three IOLs decreases compared to the centered position when subjected to a decentration of 0.3 mm or a tilt of 5°.
7.Changes in nerve fiber thickness and vascular density in macula and optic disc after femtosecond laser assisted and conventional phacoemulsification
Menglan ZHOU ; Zhengdong XU ; Changjun LAN ; Yue YANG ; Zhengyang LUO ; Zhuang MIAO ; Biao LI
International Eye Science 2024;24(9):1461-1465
AIM: To observe the changes of nerve fiber thickness and vessel density in macula and optic disc following femtosecond laser-assisted and conventional phacoemulsification cataract surgery through optical coherence tomography angiography(OCTA).METHODS: A total of 65 cases(85 eyes)that diagnosed with age-related cataract and received surgery in Aier Eye Hospital(East of Chengdu)were included in this prospective nonrandomized controlled study. The patients were divided into two groups according to the surgery choice, with 23 cases(30 eyes)in femtosecond laser assisted group, and 42 cases(55 eyes)in traditional phacoemulsification group. OCTA was used to compare the changes in central macular thickness, thickness of nerve fiber layer in optic disc, vessel density and blood perfusion preoperatively, and at 1 d and 1 mo postoperatively.RESULTS: BCVA of patients in the two groups was significantly improved and IOP was significantly reduced at 1 mo postoperatively(all P<0.01). The macular nerve fiber layer thickness of the femtosecond laser-assisted group was increased at 1 d and 1 mo postoperatively(all P<0.05), while there was no statistical difference in the traditional phacoemulsification group before and after surgery(all P>0.05); there were significant differences in nerve fiber layer thickness in optic disc, vessel density and blood perfusion in both macula and optic disc of the traditional phacoemulsification group(all P<0.05), but there were no differences in the femtosecond laser assisted group(all P>0.05). Furthermore, there were no significant differences in foveal avascular zone area in the two groups of patients(all P>0.05).CONCLUSION: Femtosecond laser-assisted cataract surgery had less impact on retinal vessels.
8.Repeatability of wavefront aberration measured by adaptive optics visual simulator and agreement of OPD-Scan Ⅲ
Yan WANG ; Xuan LIAO ; Changjun LAN ; Biao LI ; Zhuang MIAO ; Qingqing TAN ; Suyun QIN ; Huan HUANG
International Eye Science 2024;24(5):810-815
AIM: To assess the repeatability and agreement of higher-order aberration obtained by adaptive optics visual simulator(VAO)compared with OPD-Scan Ⅲ.METHODS: A cross-sectional study was conducted from August to September 2023, including a total of 204 patients(204 eyes)with myopia whose right eyes were measured. The examinations were performed by the same skilled examiner using both devices separately. The VAO device was used to measure higher order aberrations of orders 3 to 6 at a pupil diameter of 4.5 mm, while both the VAO and OPD-Scan Ⅲ devices were utilized to measure total higher-order aberration(tHOA), spherical aberration(SA), coma aberration(Coma), and trefoil aberration(Trefoil)of the entire eye at pupil diameters ranging from 3 to 6 mm. Furthermore, the repeatability of whole eye aberration measurements obtained with the VAO device was evaluated and the agreement of the two devices was assessed.RESULTS: The whole-eye higher-order aberrations measured by VAO demonstrated excellent repeatability(0.767≤ICC≤0.941, Sw<0.01 μm, TRT<0.1 μm). There was no statistically significant difference in Coma measured by VAO or OPD-Scan Ⅲ for pupil diameters ranging from 4 to 6 mm(P>0.05), while a statistically significant difference was observed in whole-eye tHOA of other pupil diameters(all P<0.05). The agreement of aberration measurements for each order between VAO and OPD-Scan Ⅲ for 3 mm pupil diameters, SA at 4 and 5 mm pupil diameter and Coma at 4 mm pupil diameter showed a 95% limit of agreement(LoA)<0.1, indicating good agreement; however, poor agreement was found for the remaining aberration measurements at different pupil diameters, with a 95%LoA>0.1, and there were significant differences in higher-order aberrations measured by two devices under a pupil diameter of 3 mm(r=0.218-0.317, P<0.01), 4 mm(r=0.406-0.672, P<0.01), 5 mm(r=0.538-0.839, P<0.01 and r=0.030-0.109, P>0.01)and 6 mm(r=0.369-0.766, P<0.01).CONCLUSION: The VAO demonstrates favorable repeatability when assessing whole-eye higher order aberration under pupil diameters of 3-6 mm. However, there is inadequate agreement and interchangeability in whole-eye higher order aberration at 3-6 mm pupil diameter between VAO and OPD-Scan Ⅲ for clinical purposes.
9.Efficacy and safety of ultrasound cycloplasty in the treatment of refractory glaucoma
Zhuang MIAO ; Changjun LAN ; Zhengdong XU ; Yue YANG ; Menglan ZHOU
International Eye Science 2024;24(6):985-989
AIM: To evaluate clinical efficacy and safety of ultrasound cycloplasty(UCP)in the treatment of refractory glaucoma.METHODS:From June 2021 to October 2022, a total of 17 patients(17 eyes)with refractory glaucoma were enrolled in this prospective study, and they all underwent UCP. The patients underwent 6 mo followed-up post-treatment, and the intraocular pressure(IOP), pain grade score, IOP lowering drugs, success rate and occurrence of complications were documented.RESULTS:The IOP was significantly decreased from 51.98±7.80 mmHg before UCP to 32.54±13.21 mmHg at 1 d, 22.38±11.98 mmHg at 1 wk, 22.63±10.78 mmHg at 1 mo, 26.05±9.17 mmHg at 3 mo, and 23.73±9.60 mmHg at 6 mo postoperatively(all P<0.01). The percentage of IOP reduction after treatment was 36.25%, 57.10%, 56.35%, 49.16% and 54.09% at 1 d, 1 wk, 1, 3, and 6 mo, respectively. The pain grade scores were decreased(P<0.01). There was a statistically significant reduction in the use of IOP lowering medications(P=0.008). At 6 mo postoperatively, 2 eyes(12%)were complete success, 11 eyes(65%)were qualified success, and 4 eyes(24%)were failure. The main complication observed was anterior chamber inflammation in 1 eye(6%), foreign body sensation in 2 eyes(12%), subconjunctival hemorrhage in 2 eyes(12%), and conjunctival congestion in 6 eyes(35%). All symptoms spontaneously resolved within 1 wk without requiring any specific treatment. One case of choroidal detachment(6%)occurred on 10 d postoperatively, but recovered after orally treated by prednisone acetate for 1 mo. No other serious complications, such as hyphema, corectopia, synechia or macular edema were reported.CONCLUSION:UCP is safe and efficacious in treating refractory glaucoma, reducing IOP and alleviating ocular pain symptoms, while maintaining a favorable safety profile.
10.Evaluation of optical performance of aspherical intraocular lens in vitro by optical bench
Lixuan XIE ; Xuan LIAO ; Changjun LAN ; Qingqing TAN ; Ruolin PAN ; Yuling TANG ; Suyun QIN ; Yan WANG
Chinese Journal of Experimental Ophthalmology 2024;42(3):240-247
Objective:To evaluate the optical performance of two aspheric intraocular lenses (IOL) AcrySof IQ SN60WF and Proming A1-UV with identical negative spherical aberration values, using the optical bench OptiSpheric IOL R&D through an in vitro study. Methods:The optical performance of + 20.0 D blue-light filtering SN60WF and monofocal high-order aspheric non blue-light filtering A1-UV IOL was evaluated through cornea models with the spherical aberration of 0 μm (ISO-1) and + 0.28 μm (ISO-2) under apertures of 3.0 mm and 4.5 mm via the optical bench OptiSpheric IOL R&D.The modulation transfer function (MTF) and USAF 1951 resolution test chart were employed to measure the IOL with centering, decentration of 0.3, 0.5, 0.7, 0.9 and 1.1 mm, as well as tilt of 3°, 5°, 7°, 9° and 11°.The spectral transmittance of IOL was measured with the UV-3300 UV-VIS spectrophotometer.Results:Compared with the A1-UV IOL, the spectral transmittance of SN60WF for blue light with wavelengths of 400-500 nm was significantly reduced, which effectively reduced the passage of blue light.At an aperture of 3.0 mm, the MTF values at 100 lp/mm spatial frequency for the centered SN60WF and A1-UV were 0.576 and 0.598 under ISO-1 corneal measurement conditions, 0.564 and 0.563 under ISO-2 conditions.At an aperture of 4.5 mm, the MTF values were 0.238 and 0.404 under ISO-1 corneal measurement conditions, and 0.438 and 0.339 under ISO-2 conditions.The MTF values of A1-UV and SN60WF at 3.0 mm aperture and 100 lp/mm spatial frequency under ISO-1 corneal measurement conditions were larger than those under ISO-2 corneal measurement conditions.Under ISO-1 corneal measurement conditions with a 3.0 mm aperture, A1-UV had a better optical quality compared to SN60WF, whereas under ISO-2 corneal measurement conditions, the optical quality of both IOLs was similar.Under the 3.0 mm aperture, the MTF values of SN60WF and A1-UV at a decentration of 0.3 mm and 100 lp/mm spatial frequency were 0.414 and 0.571 under ISO-1 corneal measurement conditions, 0.438 and 0.512 under ISO-2 corneal measurement conditions, respectively.The MTF values of SN60WF and A1-UV at a tilt of 3° were 0.522 and 0.597 under ISO-1 corneal measurement conditions, and 0.532 and 0.531 under ISO-2 corneal measurement conditions.The MTF values and USAF resolution test chart of A1-UV had no significant change between the two corneal measurement conditions.When subjected to equal degrees of decentration or tilting, except for the ISO-1 corneal measurement conditions at a 4.5 mm aperture, the MTF values of A1-UV showed a gradual decline across various spatial frequencies compared to SN60WF.With the increase in aperture size, the impact of IOL decentration or tilting on MTF values and USAF 1951 resolution test chart became more notable for A1-UV relative to SN60WF.Conclusions:The SN60WF IOL effectively filters blue light within the wavelength range of 400-500 nm.However, when both IOL experience decentration greater than 0.3 mm or tilting beyond 3°, the optical quality of the IOL will decline.A1-UV has a distinct advantage over SN60WF in terms of resistance to both decentration and tilting-induced optical performance degradation in vitro.

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