Background Anterior capsular contraction syndrome is a potential complication of continuous curvilinear capsulorhexis （CCC）. Three neodymium： yttrium-aluminum-garnet （Nd：YAG） laser relaxing incisions decrease an...Background Anterior capsular contraction syndrome is a potential complication of continuous curvilinear capsulorhexis （CCC）. Three neodymium： yttrium-aluminum-garnet （Nd：YAG） laser relaxing incisions decrease anterior capsular contraction but the mechanism is unknown. The present study analyzed the biomechanical mechanism of three Nd：YAG laser relaxing incisions made to reduce anterior capsular contraction. Methods A three-dimensional control model and a three-dimensional Nd：YAG model of the anterior capsule with an opening diameter of 6 mm were created. Three incisions of 1 mm in length were made centrifugally at intervals of 120~ around the opening circle. The stress alterations of the anterior capsule after CCC with and without Nd：YAG relaxation were numerically simulated and compared. Results In the control model, the stress was axially uniform in the inner area and relatively high near the inner rim of the opening. Meanwhile, in the Nd：YAG model, the stress level was very low in the inner opening areas, especially near the three incisions. The relaxing incisions in the Nd：YAG model significantly released the relatively high stress on the anterior capsule. Additionally, there was a high stress gradient near the relaxing incisions. Conclusion Biomechanical effects of stress release may be the preventive mechanism of Nd：YAG incision against anterior capsular contraction syndrome.展开更多
AIM： To estimate the effectiveness of phacoemulsification and foldable intraocular lens（IOL） implantation combined with transpupillary silicone oil removal.METHODS： There were 168 eyes of 168 candidate patients wi...AIM： To estimate the effectiveness of phacoemulsification and foldable intraocular lens（IOL） implantation combined with transpupillary silicone oil removal.METHODS： There were 168 eyes of 168 candidate patients with cataract and silicone oil-filled eyes recruited in our study. All of the patients received the intraocular silicone oil removal surgery by transpupillary drainage and cataract extraction by phacoemulsification. Then the IOL implantation were also performed through corneal incision. RESULTS： The surgery was successfully completed in all eyes. Best corrected visual acuity（BCVA） and postoperative complications were recorded in three months after surgery. There were 143 eyes with BCVA improved, otherwise 25 eyes remained stable at the last follow-up visit. The mean BCVA statistically improved from 20/400±0.02 to 20/100±0.15（P〈0.001） and mean postoperative IOP was 13.85±2.18 mm Hg（P=0.415）. No intra-operative complications were reported.CONCLUSION： Phacoemulsification combined with transpupillary removal of silicone oil is a safe and simple effective method. In general, it enables quick recovery of visual acuity with less complication rate.展开更多
Femtosecond laser(FSL)cataract surgery is in its infancy but is rapidly gaining popularity due to the improved consistency and predictability for corneal incisions and anterior capsulorhexis.It enables subsequently le...Femtosecond laser(FSL)cataract surgery is in its infancy but is rapidly gaining popularity due to the improved consistency and predictability for corneal incisions and anterior capsulorhexis.It enables subsequently less phacoemulsification energy and time to be employed,which has gains in terms of reduced corneal oedema.In addition,the FSL allows better circularity of the anterior capsulotomy,capsule overlap,intraocular lens(IOL)placement and centration of the IOL.These advantages have resulted in improved visual and refractive outcomes in the short term.Complication rates are low which reduce with surgeon experience.This review article focuses on the Alcon LenSx system.展开更多
Background:Femtosecond-laser assisted clear cornea cataract surgery may hold promise in safer and more effective procedures.We decided to perform a comparative study to standard manual incision phacoemulsification sur...Background:Femtosecond-laser assisted clear cornea cataract surgery may hold promise in safer and more effective procedures.We decided to perform a comparative study to standard manual incision phacoemulsification surgery.Methods:This is a single-center,single-intervention,and prospective comparative data evaluation of 133 consecutive cases subjected to cataract surgery.Group-A(Phaco),manual capsulorhexis&ultrasound phacoemulsification(n=66);Group-B femtosecond-laser assisted capsulorhexis and lens fragmentation(n=67),employing the LenSx laser(Alcon Surgical,Ft.Worth,TX).All cases were evaluated for refraction,visual acuity,keratometry,tomography,pachymetry,endothelial cell counts,intraocular pressure,and type of intraocular lens(IOL)implanted.The groups were matched for age,gender,pre-operative vision metrics,and cataract grade,and were followed up to 1 year.Results:In group-A post-operative uncorrected distance visual acuity(UDVA)was 20/20 or better in 61.5%and 20/25 or better in 78.5%of the eyes.The femtosecond laser group-B had improved outcomes(p=0.075 and p=0.042,respectively):post-operative UDVA was 20/20 or better in 62.7%of the eyes and 20/25 or better in 85.1%.Linear regression scatterplots of achieved versus attempted spherical equivalent had excellent regression coefficients(r^(2)=0.983 in group-A and 0.979 in group-B).There were 75.2%cases in group-A and 80.6%in group-B(p=0.8732)within±0.50 D of targeted refractive equivalent.Slight trend of under-correction was noted in group-A.Average residual manifest cylinder in the toric subgroup-A was-0.50 D(95%Limit-of-Agreement(LoA)=-0.78 D),and in toric subgroup-B-0.45 D(LoA=-0.45 D).Conclusions:Mean spherical equivalent refraction and visual acuity are comparable with laser cataract surgery compared with manual capsulorhexis&ultrasound phacoemulsification.Improved astigmatism correction may be among the benefits of femtosecond laser–assisted cataract surgery.Transient corneal edema may be a first day transient disadvantage in femtosecond laser–assisted展开更多
AIM:To investigate the influence of ophthalmic viscoelastic devices(OVDs)and different surgical approaches on the intraocular pressure(IOP)before and after creation of the curvilinear circular capsulorhexis(CCC)as a m...AIM:To investigate the influence of ophthalmic viscoelastic devices(OVDs)and different surgical approaches on the intraocular pressure(IOP)before and after creation of the curvilinear circular capsulorhexis(CCC)as a measure for anterior chamber stability during this maneuver.METHODS:Prospective experimental WetLab study carried out on enucleated porcine eyes.IOP was measured before and after CCC with the iCare Rebound tonometer(iCare ic200;iCare Finland Oy,Vantaa,Finland).The OVDs used were a cohesive one[Z-Hyalin,Carl Zeiss Meditec AG,Germany;hyaluronic acid(HA)]and a dispersive[Z-Celcoat,Carl Zeiss Meditec AG,Germany;hydroxy propylmethylcellulosis(HPMC)].The CCC was created using Utrata forceps or 23 g microforceps in different combinations with the OVDs.RESULTS:Using the Utrata forceps the IOP dropped from 63.65±6.44 to 11.25±3.63 mm Hg during the CCC.The use of different OVDs made no difference.Using the 23 g microforceps the IOP dropped from 65.35±8.15 to 36.55±6.09 mm Hg.The difference between IOP drop using either Utrata forceps or 23 g microforceps was highly significant regardless of the OVD used.CONCLUSION:Using the sideport for the creation of the capsulorhexis leads to a lesser drop in IOP during this maneuver compared to the main incision in enucleated porcine eyes.The use of different OVD has no significant influence on IOP drop.展开更多
Objective:To explore the circular capsulorhexis method and its clinical effect in phacoemulsification of hypermature cataract without staining.Methods:In this prospective randomized case-control study,22 patients(22 e...Objective:To explore the circular capsulorhexis method and its clinical effect in phacoemulsification of hypermature cataract without staining.Methods:In this prospective randomized case-control study,22 patients(22 eyes)with hypermature cataract were randomly divided into a staining agent group(10 cases,10 eyes)and a non-staining agent group(12 cases,12 eyes).Both groups underwent phacoemulsification with foldable intraocular lens implantation under topical anesthesia.In the staining agent group,0.5%indocyanine green was used to stain the anterior lens capsule to assist in circular capsulorhexis;in the non-staining agent group,after puncturing the anterior lens capsule and aspirating the liquefied cortical material,the capsular bag was filled with viscoelastic agent to increase the contrast prior to circular capsulorhexis.The operability of the anterior capsule without staining in capsulorhexis was observed,and the effect of capsulorhexis,diameter of capsulorhexis opening,and operative time were compared and analyzed between the two groups.Results:Both groups successfully underwent circular capsulorhexis,with a success rate of 100%.The diameters of capsulorhexis opening in the staining agent group and non-staining agent group were 5.68±0.15 mm and 5.54±0.16 mm,respectively,without any statistical difference between the groups(P>0.05);the operative time of the staining agent group(40.40±5.42 s)was shorter than that of the non-staining agent group(50.92±3.97 s),and the difference was statistically significant(P<0.001).In both groups,phacoemulsification was successful,and intraocular lens were implanted into the capsular bags;their visual acuity showed significant improvement during the 1-month follow-up period after surgery,without any surgical complications.Conclusion:In hypermature cataract,injecting viscoelastic agent into the capsular bag for volume replacement,given a lack of capsule staining agent,can increase the contrast for capsulorhexis and reduce the risk of large capsular bag collapse on the zonula展开更多
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
基金This study was supported by grants from National Natural Science Foundation of China （No. 81173412）, Beijing Science and Technology Project （Z111107067311056） and Beijing Natural Science Foundation （No. 7122046）.
文摘Background Anterior capsular contraction syndrome is a potential complication of continuous curvilinear capsulorhexis （CCC）. Three neodymium： yttrium-aluminum-garnet （Nd：YAG） laser relaxing incisions decrease anterior capsular contraction but the mechanism is unknown. The present study analyzed the biomechanical mechanism of three Nd：YAG laser relaxing incisions made to reduce anterior capsular contraction. Methods A three-dimensional control model and a three-dimensional Nd：YAG model of the anterior capsule with an opening diameter of 6 mm were created. Three incisions of 1 mm in length were made centrifugally at intervals of 120~ around the opening circle. The stress alterations of the anterior capsule after CCC with and without Nd：YAG relaxation were numerically simulated and compared. Results In the control model, the stress was axially uniform in the inner area and relatively high near the inner rim of the opening. Meanwhile, in the Nd：YAG model, the stress level was very low in the inner opening areas, especially near the three incisions. The relaxing incisions in the Nd：YAG model significantly released the relatively high stress on the anterior capsule. Additionally, there was a high stress gradient near the relaxing incisions. Conclusion Biomechanical effects of stress release may be the preventive mechanism of Nd：YAG incision against anterior capsular contraction syndrome.
基金Supported by National Basic Research Program of China (973 Program, No.2013CB967503)General Project of the National Natural Science Fund (No.81170855)
文摘AIM： To estimate the effectiveness of phacoemulsification and foldable intraocular lens（IOL） implantation combined with transpupillary silicone oil removal.METHODS： There were 168 eyes of 168 candidate patients with cataract and silicone oil-filled eyes recruited in our study. All of the patients received the intraocular silicone oil removal surgery by transpupillary drainage and cataract extraction by phacoemulsification. Then the IOL implantation were also performed through corneal incision. RESULTS： The surgery was successfully completed in all eyes. Best corrected visual acuity（BCVA） and postoperative complications were recorded in three months after surgery. There were 143 eyes with BCVA improved, otherwise 25 eyes remained stable at the last follow-up visit. The mean BCVA statistically improved from 20/400±0.02 to 20/100±0.15（P〈0.001） and mean postoperative IOP was 13.85±2.18 mm Hg（P=0.415）. No intra-operative complications were reported.CONCLUSION： Phacoemulsification combined with transpupillary removal of silicone oil is a safe and simple effective method. In general, it enables quick recovery of visual acuity with less complication rate.
文摘Femtosecond laser(FSL)cataract surgery is in its infancy but is rapidly gaining popularity due to the improved consistency and predictability for corneal incisions and anterior capsulorhexis.It enables subsequently less phacoemulsification energy and time to be employed,which has gains in terms of reduced corneal oedema.In addition,the FSL allows better circularity of the anterior capsulotomy,capsule overlap,intraocular lens(IOL)placement and centration of the IOL.These advantages have resulted in improved visual and refractive outcomes in the short term.Complication rates are low which reduce with surgeon experience.This review article focuses on the Alcon LenSx system.
基金Unrestricted Funding from Alcon Laboratories(IIT 10247941).
文摘Background:Femtosecond-laser assisted clear cornea cataract surgery may hold promise in safer and more effective procedures.We decided to perform a comparative study to standard manual incision phacoemulsification surgery.Methods:This is a single-center,single-intervention,and prospective comparative data evaluation of 133 consecutive cases subjected to cataract surgery.Group-A(Phaco),manual capsulorhexis&ultrasound phacoemulsification(n=66);Group-B femtosecond-laser assisted capsulorhexis and lens fragmentation(n=67),employing the LenSx laser(Alcon Surgical,Ft.Worth,TX).All cases were evaluated for refraction,visual acuity,keratometry,tomography,pachymetry,endothelial cell counts,intraocular pressure,and type of intraocular lens(IOL)implanted.The groups were matched for age,gender,pre-operative vision metrics,and cataract grade,and were followed up to 1 year.Results:In group-A post-operative uncorrected distance visual acuity(UDVA)was 20/20 or better in 61.5%and 20/25 or better in 78.5%of the eyes.The femtosecond laser group-B had improved outcomes(p=0.075 and p=0.042,respectively):post-operative UDVA was 20/20 or better in 62.7%of the eyes and 20/25 or better in 85.1%.Linear regression scatterplots of achieved versus attempted spherical equivalent had excellent regression coefficients(r^(2)=0.983 in group-A and 0.979 in group-B).There were 75.2%cases in group-A and 80.6%in group-B(p=0.8732)within±0.50 D of targeted refractive equivalent.Slight trend of under-correction was noted in group-A.Average residual manifest cylinder in the toric subgroup-A was-0.50 D(95%Limit-of-Agreement(LoA)=-0.78 D),and in toric subgroup-B-0.45 D(LoA=-0.45 D).Conclusions:Mean spherical equivalent refraction and visual acuity are comparable with laser cataract surgery compared with manual capsulorhexis&ultrasound phacoemulsification.Improved astigmatism correction may be among the benefits of femtosecond laser–assisted cataract surgery.Transient corneal edema may be a first day transient disadvantage in femtosecond laser–assisted
文摘AIM:To investigate the influence of ophthalmic viscoelastic devices(OVDs)and different surgical approaches on the intraocular pressure(IOP)before and after creation of the curvilinear circular capsulorhexis(CCC)as a measure for anterior chamber stability during this maneuver.METHODS:Prospective experimental WetLab study carried out on enucleated porcine eyes.IOP was measured before and after CCC with the iCare Rebound tonometer(iCare ic200;iCare Finland Oy,Vantaa,Finland).The OVDs used were a cohesive one[Z-Hyalin,Carl Zeiss Meditec AG,Germany;hyaluronic acid(HA)]and a dispersive[Z-Celcoat,Carl Zeiss Meditec AG,Germany;hydroxy propylmethylcellulosis(HPMC)].The CCC was created using Utrata forceps or 23 g microforceps in different combinations with the OVDs.RESULTS:Using the Utrata forceps the IOP dropped from 63.65±6.44 to 11.25±3.63 mm Hg during the CCC.The use of different OVDs made no difference.Using the 23 g microforceps the IOP dropped from 65.35±8.15 to 36.55±6.09 mm Hg.The difference between IOP drop using either Utrata forceps or 23 g microforceps was highly significant regardless of the OVD used.CONCLUSION:Using the sideport for the creation of the capsulorhexis leads to a lesser drop in IOP during this maneuver compared to the main incision in enucleated porcine eyes.The use of different OVD has no significant influence on IOP drop.
基金the First Affiliated Hospital of Xi’an Medical College(XYFYPT-2023-01)Medical Research Project of Xi’an Science and Technology Bureau(21YXYJ0127).
文摘Objective:To explore the circular capsulorhexis method and its clinical effect in phacoemulsification of hypermature cataract without staining.Methods:In this prospective randomized case-control study,22 patients(22 eyes)with hypermature cataract were randomly divided into a staining agent group(10 cases,10 eyes)and a non-staining agent group(12 cases,12 eyes).Both groups underwent phacoemulsification with foldable intraocular lens implantation under topical anesthesia.In the staining agent group,0.5%indocyanine green was used to stain the anterior lens capsule to assist in circular capsulorhexis;in the non-staining agent group,after puncturing the anterior lens capsule and aspirating the liquefied cortical material,the capsular bag was filled with viscoelastic agent to increase the contrast prior to circular capsulorhexis.The operability of the anterior capsule without staining in capsulorhexis was observed,and the effect of capsulorhexis,diameter of capsulorhexis opening,and operative time were compared and analyzed between the two groups.Results:Both groups successfully underwent circular capsulorhexis,with a success rate of 100%.The diameters of capsulorhexis opening in the staining agent group and non-staining agent group were 5.68±0.15 mm and 5.54±0.16 mm,respectively,without any statistical difference between the groups(P>0.05);the operative time of the staining agent group(40.40±5.42 s)was shorter than that of the non-staining agent group(50.92±3.97 s),and the difference was statistically significant(P<0.001).In both groups,phacoemulsification was successful,and intraocular lens were implanted into the capsular bags;their visual acuity showed significant improvement during the 1-month follow-up period after surgery,without any surgical complications.Conclusion:In hypermature cataract,injecting viscoelastic agent into the capsular bag for volume replacement,given a lack of capsule staining agent,can increase the contrast for capsulorhexis and reduce the risk of large capsular bag collapse on the zonula
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.
