1.Glaucoma gene therapy:obstacles and challenges
Ophthalmology in China 1993;0(01):-
Trabecular meshwork,ciliary body,retina and optic nerve will be the targets for glaucoma gene therapy.The strategies include lowering intraocular pressure,neuroprotection and preventing wound healing in glaucoma filtration surgery. Overexpression of certain gene(s)in trabecular meshwork to increase the resistance to aqueous humor outflow would be an ideal method to create an animal model of glaucoma.Even though great progress has been made in this field,significant challenges and obstacles, including lack of tissue specific promoter,problems in long-term gene expression and side effects,still remain to be resolved.
2.Application of visual stimulated-fMRI in occipital lobe injury cases-a pilot study
Baoke HOU ; Shihui WEI ; Lin MA ; Jing HAN
Ophthalmology in China 1994;0(02):-
Objective To observe the results of visual functional MRI(fMRI)of injury side with those of uninjured side,in patients with visual field defects and retrochiasmastic tumor.The potential clinical usefulness of visual fMRI data during functional examination on visual centre,defining the tumor field and surgery,was evaluated in patients with occipital lobe tumour.Design Case series.Participants Two patients with occipital lobe tumor and homonymous visual field defects,injury sides contrast with uninjured ones.Methods Patients were studied with fMRI using monocular checker stimulation(5Hz).The data obtained were analyzed with statistical parametric maps software(P
3.Expression of heat shock protein 27 induced in the experimental rat glaucoma model
Yan LI ; Yuansheng YUAN ; Yong ZENG ; Zhuangfei CHEN ; Wei ZHAO ; Le DAI
Ophthalmology in China 1994;0(02):-
Objective To evaluate changes in retinal expression of three heat shock proteins(HSPs)HSP27,HSP70 and HSP90 in normal and experimental glaucomatous rats's retina,and to explore the potential relationship between HSPs with glaucoma optic neuropathy.Design Experimental study.Participants 60 Wistar rats.Methods Rats were randomly divided into ocular hypertension group(n=30)and sham control group(n=30).The right eye was designed as the experimental eye,and the left as the control eyes.Intraocular pressure(IOP)was elevated by using underwater bipolar electro coagulation condensate 3 episcleral and limbal veins on the right eye of rats to establish of animal models of glaucoma.IOP were monitored twice weekly with a Tonopen.In treated eyes,IOP ranged from 27 to 35 mmHg throughout the study.Rats were killed with euthanasia at 10,20,or 60 days following the occurrence of ocular hypertension,with retina dissected free and protein isolated.Protein was used for Western blot analysis and probed with specific HSP antibodies,and normalized to ?-actin levels.Main Outcome Measures IOP,Western bolt.Results Western blot analysis demonstrated that HSP27 protein levels in the retinas were elevated as much as 197% at 10,20 and 60 days following the induction of ocular hypertension.No changes in protein levels were observed for HSP70 or HSP90 in retina from ocular hypertensive eyes.Conclusions The stress protein HSP27 is upregulated in retinas from ocular hypertensive rats.No changes in HSP70 or HSP90 were observed.The upregulation in HSP27 appears to be a gene specific event associated with elevated IOP,its expression may be a potential relationship associated with optic neuropathy in glaucoma.
4.Influence of the phacoemulsification with posterior continuous curvilinear capsulorhexis and anterior vitrectomy on after cataract:a Meta-analysis
Xiaolei YIN ; Jian YE ; Rongdi YUAN
Ophthalmology in China 1994;0(02):-
Objective To evaluate the functional outcomes of the phacoemulsification(Phaco)with posterior continuous curvilinear capsulorhexis(PCCC),or with PCCC and anterior vitrectomy(AV)on after cataract.Design Meta analysis based on the reference searching.Participants A comprehensive electric search in MEDLINE,CNKI,CBMdisc,VIP information,CMCC,CCPD,SSreader,21dmedia and a manual search in related textbooks,journals,congress articles and their references in English and Chinese.Methods Strictly include and exclude the relevant articles from the resource with statistical criterion and get the needing data.Statistically analysed the data with software of Review Manager4.2.2,SPSS10.0.Heterogeneity of the included articles was tested that used to select appropriate effect model to Meta-analysis.Treatment effect was measured as odds ratio between Phaco with PCCC group and Phaco with PCCC+AV group.Change the selected effect model and calculate the fail-safe number(Nfs)to assess the sensitivity and specificity of the research.Main Outcome Measures Sensitivity,heterogeneity,the according confidence intervals(CI)and Nfs.Results Six studies were included,with a sum of 305 eyes.With the outcomes of heterogeneity test,the fixed effect model was used in both groups to calculate OR.The pooled OR of after cataract was 0.13(95%CI is 0.06-0.25).Sensitivity analysis demonstrated that no disproportionate influences of individual study.And Nfs=76.8,the result was confirmed.Conclusion Phacoemulsification with posterior continuous curvilinear capsulorhexis and anterior vitrectomy is superior to phacoemulsification with posterior continuous curvilinear capsulorhexis on preventing after cataract.
5.Clinical evaluation of preloaded aspheric IOL implantation
Yonghua LI ; Zhende LIN ; Ayong YU ; Shuke LUO
Ophthalmology in China 1994;0(02):-
Objective To evaluate the clinical efficacy after implantation of preloaded aspheric intraocular lens.Design Retrospective case series.Participants 74 patients(82 eyes)with age-related cataract:38 patients(43 eyes)in group A(control group),36 patients(39 eyes)in group B(case group).Methods 74 patients(82 eyes)were randomly selected to receive phacoemulsification with KS-3(group A)and KS-3Ai(group B)IOL implantation.The wavefront aberrations and contract sensitivity were measured 3 months post-operatively.Main Outcome Measures Wavefront aberrations and contract sensitivity.Results No complications occurred in both gruops.In 1.0deg,0.7deg,the mean contract sensitivity in group A were lower than those in group B(t =3.69,2.71;P
6.Accuracy of intraocular lens power prediction by using six different formulas
Yan JIANG ; Yuying SHI ; Wenli YANG
Ophthalmology in China 1994;0(02):-
Objective To compare the accuracy of intraocular lens(IOL)power calculations by using 6 formulas(SRK-T,Haigis,Binkhorst-Ⅱ,Hoffer Q,Holladay-1,SRK-Ⅱ)in different axial lengths of the eye,in order to improve the accuracy of predicating IOL powers for patients after cataract surgery.Design Retrospective comparative clinical analysis.Participants 169 patients(169 eyes)with age-related cataract underwent regular phacoemulsification and posterior chamber IOL implantation.Methods 169 eyes with cataract were divided into five groups according to the axial lengths:AXL≤22mm,22mm28.4mm.The axial lengths and keratometry of the 169 eyes were measured with A-mode ultrasound before operation,and the actual postoperative refraction was measured with the methods of computer and retinoscopy optometry when patients could gain best corrected visual acuity one month after surgery or later.Inputting the axial lengths,keratometry and IOL powers into A-mode ultrasound,the predicted postoperative refraction was calculated with SRK-T,Haigis,Binkhorst-Ⅱ,Hoffer Q,Holladay-1,SRK-Ⅱ formulas,and the differences of predicted and actual postoperative refractions in different axial lengths were compared.Main Outcome Measures The absolute value with the differences of the predicted and actual postoperative refractions,i.e.absolute predicted errors.Results(1)Comparing the difference of predicted and actual postoperative refraction,there was no statistical significance between the five formulas in the groups of axial length(AXL)≤22mm,22mm28.4mm,but the average absolute predicted error of Haigis and SRK-T formulas is significantly smaller than SRK-Ⅱand Binkhorst-Ⅱ formulas.Conclusions In existing sample size,there was no obvious influence on postoperative refraction when using other five formulas except Binkhorst-Ⅱ.But in the extremely long AXL group,Haigis and SRK-T formulas have some ascendancy over the other formulas.
7.Comparison of higher-order aberrations between implantations of aspherical intraocular lens and spherical intraocular lens
Haike GUO ; Hongyang ZHANG ; Haiwu LI ; Haiying JIN ; Yanlei CHEN
Ophthalmology in China 1994;0(02):-
Objective To compare intraindividual higher-order aberrations(HOA)after implantation of aspherical and spherical intraocular lenses(IOL).Design Prospective,case-controlled study.Participants 33 patients(66 eyes)were between 50 and 76 years of ages.The patients with bilateral senile cataracts were operated with phacoemulsification and IOL implantation.All the patients had no other ocular pathologies and no previous ophthalmic surgery.Patients with keratometric astigmatism higher than-2.0 diopters(D)were excluded from the study.Methods Wavefront aberration measurements of 33 patients(66 eyes)after implantation of a spherical IOL(Canon Staar KS-3)in one eye and an aspherical IOL(Cannon Staar KS-3Ai)in the contralateral eye were analyzed.The eyes were randomly assigned to groups of the spherical IOL or the aspherical IOL.Third-order,4th-order,5th-order,total HOA root-mean-squares(RMS),and 4th-order spherical aberrations(Z40)were compared 3 months after surgery.Main Outcome Measures Visual acuity(VA),the best corrected visual acuity(BCVA),the centrality of IOL,refraction data,diameter of pupil size,3rd-order,4th-order,5th-order and total HOA RMS,and 4th-order spherical aberration(Z40)RMS were measured.Results Fourth-order aberration RMS(0.193?0.098?m),Z40 RMS(0.037?0.099?m),total HOA RMS(0.498?0.072?m)in the aspherical IOL group were lower than those with the spherical IOL(0.403?0.155?m,0.381?0.142?m,0.737?0.164?m,respectively)at 6mm pupil diameter.For 3rd-and 5th-order RMS at 6mm pupil diameter,total HOA RMS(at 5mm pupil diameter),no significant difference was found in both IOLs.Under mesopic conditions,ten patients(30%)with an aspheric IOL had better contrast sensitivity.The average myopic shift were(-0.29?0.09)D and(-0.87?0.16)D in the aspherical and spherical IOL groups at 6mm pupil diameter(P
8.Supracapsular implantation with optic capture of the posterior chamber intraocular lens in pediatric cataract
Ophthalmology in China 1994;0(02):-
Objective To assess the clinical effects of supracapsular implantation with optic capture of the posterior chamber intraocular lens in pediatric cataract.Design Retrospective case series.Participants 15 cases(17 eyes)with pediatric cataract.Methods Phacoemulsification,posterior continuous curvilinear capsulorhexis,about 4 mm in diameter,supracapsular implantation with optic capture of the posterior chamber intraocular lens in pediatric cataract were performed.Main Outcome Measures Preoperative and postoperative visual acuity,intraocular pressure,position of IOL,intraoperative and postoperative complications.Results Implantation of optic capture of the posterior chamber intraocular lens was successfully performed in 17 eyes.Positions of IOL were changed in 5 eyes after operation 6 months,from post-capsule to supra-capsule.Among these 5 eyes,opaque optic axis were found in 4 eyes.No optic axis opaque was found in 13 eyes with optic capture.The major complications of optic capture were lenticular precipitates:grade 1 in 3 eyes(18%);grade 2 in 7 eyes(41%).Anterior synechia of iris occurred in 1 eye(6%);posterior synechia of iris in 4 eyes(24%).Pupil deformity occurred in 5 eyes(29%).Conclusions Posterior continuous curvilinear capsulorhexis and supracapsular implantation with optic capture of the posterior chamber intraocular lens are safe and effective in the treatment of pediatric cataract,especially in the prevention of secondary opacification from the visual axis.
9.Capsular tension ring implantation for congenital subluxated lenses
Yu ZHENG ; Xudong SONG ; Zheng GU
Ophthalmology in China 1994;0(02):-
1.5mm)and received CTR scleral fixation.Visual acuity before and after surgery were examined.IOL tilt and decentration were measured with PentaCam system.Complications were also recorded.Main Outcome Measures Postoperative visual improvement,IOL position and complications.Results At the last postoperative examination,best corrected visual acuities of all eyes were increased(P=0.000).The mean IOL tilt was 4.33?2.96?before and 4.11?2.05?after CTR fixation,the mean decentration was 2.56?0.90mm before and 1.19?0.71mm after.No significant differences were found in IOL tilt before and after CTR fixation(P=0.844),but there were significant differences in IOL decentration(P=0.009).Posterior capsular opacification was found in 8 eyes(20.5%)during the follow-up period,and 2 eyes(5.1%)received Nd:YAG posterior capsulotomy.1 eye received IOL scleral fixation because of capsule rupture during CTR implantation.2 eyes suffered from temporary IOP elevation after surgery.No other severe complications occurred.Conclusions Phacoemulsification with CTR and IOL implantation is effective and safe for congenital subluxated lenses.CTR scleral fixation is a necessary supplement for severely subluxated lenses and progressive cases.
10.How to understand and select aspheric intraocular lens?
Ophthalmology in China 1994;0(02):-
Aspheric intraocular lenses(IOLs)have been shown to provide better quality of vision than spherical IOLs.However,these lenses are not ideal for all patients.Surgeons may have different strategies for compensating for the patients's cornea spherical aberration,targeting a postoperative spherical aberration of zero or +0.10 ?m.But we must know that the negative spherical aberration aspheric IOLs require very good centration with respect to the visual axis of the eye.