Background:The lens zonule,a circumferential system of fibres connecting the ciliary body to the lens,is responsible for centration of the lens.The structural,functional,and positional abnormalities of the zonular app...Background:The lens zonule,a circumferential system of fibres connecting the ciliary body to the lens,is responsible for centration of the lens.The structural,functional,and positional abnormalities of the zonular apparatus can lead to the abnormality of the intraocular structure,presenting a significant challenge to cataract surgery.Main text:The lens zonule is the elaborate system of extracellular fibers,which not only centers the lens in the eye but also plays an important role in accommodation and lens immunity,maintains the shape of the lens,and corrects spherical aberration.The zonules may directly participate in the formation of cataract via the immune mechanism.Abnormal zonular fibers that affect the position and shape of the lens may play an important role in the pathogenesis of angle closure disease and increase the complexity of the surgery.Capsular tension rings and related endocapsular devices are used to provide sufficient capsular bag stabilization and ensure the safety of cataract surgery procedures.Better preoperative and intraoperative evaluation methods for zonules are needed for clinicians.Conclusions:The microstructure,biomechanical properties,and physiological functions of the lens zonules help us to better understand the pathogenesis of cataract and glaucoma,facilitating the development of safer surgical procedures for cataract.Further studies are needed to carefully analyze the structure–function relationship of the zonular apparatus to explore new treatment strategies for cataract and glaucoma.展开更多
Purpose:.To compare toric intraocular lens implantation(ToricIOL).with peripheral corneal relaxing incisions(PCRIs) for astigmatism correction in patients undergoing cataract surgery.Methods: 54 patients(54 eyes) with...Purpose:.To compare toric intraocular lens implantation(ToricIOL).with peripheral corneal relaxing incisions(PCRIs) for astigmatism correction in patients undergoing cataract surgery.Methods: 54 patients(54 eyes) with more than 0.75 diopter(D).of preexisting corneal astigmatism were classified as group A(0.75-1.50D) or group B(1.75-2.50D). The patients were randomized to undergo Toric-IOL or PCRIs in the steep axis with spherical IOL implantation..Log MAR uncorrected visual acuity(Log MAR UCVA), Log MAR best corrected vi sual acuity.(Log MAR BCVA),.error of vector(|EV|), surgery induced refraction correction.(|SIRC |),.and correction rates(CR) were measured 1 month and 6 months postoperatively.Results: At 6 months postoperatively, all 54 eyes had LogMAR BCVA≤0.2. Patients who underwent PCRIs and ToricIOL with Log MAR BCVA≤0.1 showed no significant differences in group A(P=1.00) or in group B(P=0.59). Group A showed no significant differences in Log MAR UCVA(P =0.70), |EV|(P=0.13), |SIRC|(P=0.71), and CR(P=0.56)in patients underwent PCRIs and Toric-IOL. However, group B showed significant differences in Log MAR UCVA(P <0.01), |EV|(P<0.01)), |SIRC|(P<0.01), and CR(P<0.01).The Log MAR UCVA and |EV | between 1 and 6 months showed no significant differences in patients in group A. However, in group B, they are significant differences.Conclusion:.The efficacy and stability of Toric-IOL and PCRIs were equal in low astigmatic patients..Toric-IOL achieved an enhanced effect over PCRIs in higher astigmatic patients.PCRIs had the more refractive regression than Toric-IOL in 6months.展开更多
Among refractive errors,astigmatism is the most common optical aberration,where refraction changes in different meridians of the eye.It causes blurred vision at any distance and includes corneal,lenticular,and retinal...Among refractive errors,astigmatism is the most common optical aberration,where refraction changes in different meridians of the eye.It causes blurred vision at any distance and includes corneal,lenticular,and retinal astigmatism.Cataract surgery used to cause a progressive increase in the pre-exisiting corneal astigmatism because of creating a surgically induced astigmatism,for example,a large size surgery incision.The development of surgical techniques during last decades has made cataract surgery interchange to treat preoperative corneal astigmatism at time of surgery.Nowadays,three surgical approaches can be used.By placing a sutureless clear corneal incision on the steep meridian of the cornea,a preoperative corneal astigmatism less than 1.0 D can be corrected.Single or paired peripheral corneal relaxing incisions(PCRIs)provide 1.0-3.0 D corneal astigmatism correction.PCRIs are typically used for treating 1.0-1.5 D of regular corneal astigmatism,if more than 2.0 D,the risk of overcorrection and irregular astigmatism is increased.When toric intraocular lenses(IOLs)are unavailable in markets,PCRIs are still a reasonable option for patients with up to 3.0 D of pre-existing corneal astigmatism.Toric IOLs implantation can correct 1.0-4.5 D of corneal astigmatism.Several IOLs are approved to correct a high degree of corneal astigmatism with cylinder power up to 12.0 D.These approaches can be used alone or in combination.展开更多
文摘Background:The lens zonule,a circumferential system of fibres connecting the ciliary body to the lens,is responsible for centration of the lens.The structural,functional,and positional abnormalities of the zonular apparatus can lead to the abnormality of the intraocular structure,presenting a significant challenge to cataract surgery.Main text:The lens zonule is the elaborate system of extracellular fibers,which not only centers the lens in the eye but also plays an important role in accommodation and lens immunity,maintains the shape of the lens,and corrects spherical aberration.The zonules may directly participate in the formation of cataract via the immune mechanism.Abnormal zonular fibers that affect the position and shape of the lens may play an important role in the pathogenesis of angle closure disease and increase the complexity of the surgery.Capsular tension rings and related endocapsular devices are used to provide sufficient capsular bag stabilization and ensure the safety of cataract surgery procedures.Better preoperative and intraoperative evaluation methods for zonules are needed for clinicians.Conclusions:The microstructure,biomechanical properties,and physiological functions of the lens zonules help us to better understand the pathogenesis of cataract and glaucoma,facilitating the development of safer surgical procedures for cataract.Further studies are needed to carefully analyze the structure–function relationship of the zonular apparatus to explore new treatment strategies for cataract and glaucoma.
文摘Purpose:.To compare toric intraocular lens implantation(ToricIOL).with peripheral corneal relaxing incisions(PCRIs) for astigmatism correction in patients undergoing cataract surgery.Methods: 54 patients(54 eyes) with more than 0.75 diopter(D).of preexisting corneal astigmatism were classified as group A(0.75-1.50D) or group B(1.75-2.50D). The patients were randomized to undergo Toric-IOL or PCRIs in the steep axis with spherical IOL implantation..Log MAR uncorrected visual acuity(Log MAR UCVA), Log MAR best corrected vi sual acuity.(Log MAR BCVA),.error of vector(|EV|), surgery induced refraction correction.(|SIRC |),.and correction rates(CR) were measured 1 month and 6 months postoperatively.Results: At 6 months postoperatively, all 54 eyes had LogMAR BCVA≤0.2. Patients who underwent PCRIs and ToricIOL with Log MAR BCVA≤0.1 showed no significant differences in group A(P=1.00) or in group B(P=0.59). Group A showed no significant differences in Log MAR UCVA(P =0.70), |EV|(P=0.13), |SIRC|(P=0.71), and CR(P=0.56)in patients underwent PCRIs and Toric-IOL. However, group B showed significant differences in Log MAR UCVA(P <0.01), |EV|(P<0.01)), |SIRC|(P<0.01), and CR(P<0.01).The Log MAR UCVA and |EV | between 1 and 6 months showed no significant differences in patients in group A. However, in group B, they are significant differences.Conclusion:.The efficacy and stability of Toric-IOL and PCRIs were equal in low astigmatic patients..Toric-IOL achieved an enhanced effect over PCRIs in higher astigmatic patients.PCRIs had the more refractive regression than Toric-IOL in 6months.
基金Supported by Independent Research Foundation of the 305 Hospital of PLA(No.24ZZJJLW-010).
文摘Among refractive errors,astigmatism is the most common optical aberration,where refraction changes in different meridians of the eye.It causes blurred vision at any distance and includes corneal,lenticular,and retinal astigmatism.Cataract surgery used to cause a progressive increase in the pre-exisiting corneal astigmatism because of creating a surgically induced astigmatism,for example,a large size surgery incision.The development of surgical techniques during last decades has made cataract surgery interchange to treat preoperative corneal astigmatism at time of surgery.Nowadays,three surgical approaches can be used.By placing a sutureless clear corneal incision on the steep meridian of the cornea,a preoperative corneal astigmatism less than 1.0 D can be corrected.Single or paired peripheral corneal relaxing incisions(PCRIs)provide 1.0-3.0 D corneal astigmatism correction.PCRIs are typically used for treating 1.0-1.5 D of regular corneal astigmatism,if more than 2.0 D,the risk of overcorrection and irregular astigmatism is increased.When toric intraocular lenses(IOLs)are unavailable in markets,PCRIs are still a reasonable option for patients with up to 3.0 D of pre-existing corneal astigmatism.Toric IOLs implantation can correct 1.0-4.5 D of corneal astigmatism.Several IOLs are approved to correct a high degree of corneal astigmatism with cylinder power up to 12.0 D.These approaches can be used alone or in combination.
