Volume 49 · Issue 05 · 2013

The trend of the coincident cataract and glaucoma is likely to increase worldwide and it is a common finding in the aging population.The management of combined presence of cataract and glaucoma is a common clinical challenge.Due to the development of new microscopy and cataract phacoemulsification techniques,we have more choices of surgical method.And the best surgical strategy will depend on the clinicians' surgical techniques and patients' characteristics. (Chin J Ophthalmol,2013,49:385-388)

Phacoemulsification and intraocular lens implantation is the most effective treatment of cataract.Traditional intraocular lens were mainly monofocal.Postoperative patients can return to a certain distance vision or near vision,but because of the loss of accommodative power,patients must rely on glasses to complete the work of the different distances,the postoperative life there is still a lot of inconvenience.In recent years,the design of multifocal intraocular lens has been the focus of basic and applied research in cataract,but so far the researchers still could not have agreement with the strengths and weaknesses of the multifocal and monofocal intraocular lens.There are three major controversies:First of all,whether it is worth the expense of contrast sensitivity and increased visual disturbance in return for compensatory adjustment? Second,whether it is possible to really get the full range of vision and to get rid of dependence on glasses to use multifocal intraocular lens? Third,how to grasp the indications of multifocal intraocular lens to play to their strengths. (Chin J Ophthalmol,2013,49:389-391)

Nowadays,ultrasonic emulsification combined intraocular lens (IOL) implantation has been the mainstream technology for treating a cataract.In order to further improve the patients' visual quality after surgery,Toric IOL has been used in clinic.Toric IOL can correct corneal astigmatism stably,reasonably and predictably.Clinicians should pay more attention to the details and according to the patients' conditions to make personalized options when choosing Toric IOL. (Chin J Ophthalmol,2013,49:392-394)

To evaluate the long-term visual outcome and complications after bilateral congenital cataract surgery performed prior to 12 months of age.

A prospective case study.31 cases (62 eyes) of bilateral congenital cataract were included.All patients received bilateral cataract extraction combined with primary capsulotomy and anterior vitrectomy simultaneously.After the operation,all patients wore aphakic glasses during the follow-up period.The unilateral and bilateral visual acuities (VA) at the last visit were determined and post-operative complications were evaluated,and the relationship between bilateral VA and the length of the follow-up period was also analyzed.

The median age at surgery was 3.0 M (0.5 to 11 M),the median follow-up period was 4.0 years (3.0 to 8.5 years).37 out of 62 eyes (59.68%) achieved unilateral best corrected visual acuity equal or better than 0.3.27 among 31 cases (87.1%) achieved binocular best corrected visual acuity equal or better than 0.3.Binocular best corrected visual acuity improved with the increase in the follow-up period and the patients'age (R²=0.135,P=0.0024).Post-operative complications included strabismus ( 7 cases,22.58%),nystagmus ( 13 cases,41.94%),optical opacity (3 cases,9.68%),ocular hypertension (1 cases,3.23%).

Surgery for congenital cataracts performed prior to 12 months of age is safe,and most of the subjects can achieve functional vision acuity.As these children age,the bilateral best corrected visual acuity can still keep improving. (Chin J Ophthalmol,2013,49:395-398)

To assess the clinical and visual outcomes of the implantation of the Quatrix intraocular lens (IOL) and investigate the mechanism of pseudo-accommodation of these lens.

Opatients (67eyes) received cataract surgery were offered the Quatrix IOL (32 eyes) and AR40e IOL (35 eyes).The patients' refractive status,uncorrected and best corrected distance visual acuities were assessed preoperatively,1 week,1 month and 3 months after surgery.Using the Ray-tracing method,the root mean square (RMS) values of the higher order aberrations for each subject with pupil diameters of 4.0 mm under accommodative stimuli were calculated.

The mean uncorrected distance visual acuity improved significantly from 0.70 to 0.22 log MAR by the end of 3 months pos-toperative for the Quatrix group.The mean uncorrected near acuity was statistically significantly higher in the Quatrix group than in the AR40e group at the 6 months post-operative examination.The internal spherical aberration increased and changed from a positive to a negative value with increasing accommodation at 4.0 mm of pupil diameter under accommodative stimuli for the Quatrix group.The total and internal high order aberrations had no significant difference after surgery in the control group.

Results show that the Quatix IOL is safe,effective,and stable.It provided some degree of pseudo-accommodation.Flexure changes to the optics of the Quatrix IOL during accommodation could explain some of the pseudo-accommodation of this IOL. (Chin J Ophthalmol,2013,49:399-404)

To compare the spatial resolutions of dynamic optotypes at different speed levels among age-related cataract patients,older people with clear crystalline lenses and senile individuals implanted with intraocular lenses (IOL).

The control study recruited 24 patients (48 eyes) with age-related cataract scheduled for phacoemulsification surgery in our hospital between Jul.2011 and Dec.2011 in the cataract group.Twenty-three older volunteers (46 eyes) with clear crystalline lenses were enrolled in the normal group.The postoperative group consisted of 23 contemporary cases implanted with spherical monofocal non-yellow-tinted IOL and followed up for 3 months postoperatively,of which 5 cases undertook unilateral surgery for normal visual acuity of the contralateral eye.Monocular and binocular best corrected visual acuity at static condition and binocular spatial resolution of optotypes at speeds of 15,30,60 and 90 degrees per second (dps) were measured by a logarithmic visual acuity chart.Statistical analysis was performed with student's t test (with Bonferroni correction).

Binocular spatial resolutions at speeds of 15,30,60 and 90 dps were (0.29±0.16),(0.34±0.17),(0.47±0.19) and (0.52±0.17),respectively,in the cataract group,and (0.04±0.06),(0.06±0.06),(0.12±0.09) and (0.15±0.11),respectively,in the normal group.Resolution of dynamic optotypes at the four speed levels were statistically lower in the cataract group than in the normal group (t=-6.952,-7.558,-8.235,-8.737;P<0.01).Velocity dependent spatial resolution changes manifested statistically higher values in the cataract group than in the normal group,with (0.14±0.13) versus (0.03±0.05) at the interval between static and 15 dps (t_0-15dps=-3.874,P=0.001) and (0.13±0.09) versus (0.06±0.07) at the interval between 30 dps and 60 dps (t_30-60dps=-3.113,P=0.003).In the postoperative group,resolutions of dynamic optotypes at speeds of 15,30,60 and 90 dps were (0.03±0.05),(0.05±0.07),(0.11±0.10) and (0.16±0.11),respectively.Dynamic visual acuities at all the four speed levels were statistically higher in the postoperative group than in the cataract group (t=-7.336,-7.673,-8.328,-8.583;P<0.01) and compatible to that in the normal group (t=0.669,0.400,0.372,-0.504;P>0.05).Visual acuity differences between consecutive speed levels were comparable between the postoperative group and the normal group (t=0.586,-0.326,0.133,-1.600;P>0.05),while at the interval between static and 15 dps and the interval between 30 dps and 60 dps,the postoperative group exhibited lower visual acuity changes than the cataract group,with (0.03±0.04) versus (0.14±0.13) (t_0-15dps=-4.182,P<0.01) and (0.05±0.06) versus (0.13±0.09) (t_30-60dps=-3.334,P=0.002),respectively.

As the optotype's moving speed increased,spatial resolutions declined more rapidly in patients with age-related cataract.Phacoemulsification combined with IOL implantation could effectively restore the spatial resolution of dynamic optotypes. (Chin J Ophthalmol,2013,49:405-409)

To evaluate the protective effect of photochromic intraocular lens (IOL) on visible light-induced lesion in cultured retinal pigment epithelium (RPE).

It was a experimental study.A human retinal pigment epithelium cell line (ARPE-19) was used to study the protective role.Cells from the same passage were divided into the control,light exposure only,light exposure plus colorless IOL (FV-60A),light exposure plus photochromic IOL (BV-60 A),light exposure plus yellow IOL (Acrysof Natural IOL) groups.The treatments were performed when the cells grew to 90% confluency.All cells were irradiated with visible light at an illumination intensity of 60 000-61 000 lux.After the treatments,we assessed 1: cells' viability by methyl thiazolyl tetrazolium (MTT) assay; 2: the extent of apoptosis by terminal deoxynucleotidyl transferasemediated d UTP nick-end labeling (TUNEL),observing changes in the ultrastructure by transmission electron microscopy (TEM),and performing Hoechst staining to measure the apoptosis index (AI) ; 3: examining vascular endothelial growth factor (VEGF) and pigment epithelium-derived factor (PEDF) levels in the culture medium by enzyme linked immunosorbent assay (ELISA).

Measurements of the cell viability of the five groups were (0.61±0.01),(0.39±0.01),(0.46±0.01),(0.57±0.01),and (0.58±0.02),respectively.Apoptosis was significantly activated by visible light as observed in TUNEL staining and TEM.The AIs of the five groups were (0.99±0.65) %,(9.28±0.59) %,(6.54±0.37) %,(4.69±0.74) %,and (2.72±0.67) %,respectively.The levels of VEGF in the five groups were (3931.64±25.26) ng/L,(5459.38±42.69) ng/L,(4800.55±42.12) ng/L,(4561.21±46.27) ng/ L,and (4420.35±28.66) ng/L,respectively.The levels of PEDF in the five groups were (182.85±1.68) μg/L,(156.52±0.64) μg/L,(155.57±3.43) μg/L,(167.57±2.88) μg/L,and (170.90±2.99) μg/L,respectively.Comparing the photochromic IOL group with the yellow IOL group,there was no difference in cell viability (q=0.94) and PEDF levels (q=1.51) (P>0.05),but there was a significant difference between the AI (q=5.04) and VEGF levels (q=6.78) (P<0.05).Comparing the photochromic IOL group with the colorless IOL group,there were significant differences in cell viability (q=18.92),AI (q=4.78),VEGF (q=11.52) and PEDF levels (q=4.96) (P<0.05).

Photochromic IOL can abate the degree of acute photodamage of RPE.The protective efficiency was the highest when using the yellow Acrysof Natural IOL,followed by photochromic IOL and colorless IOL. (Chin J Ophthalmol,2013,49:410-415)

To assess the quality of vision in the early stage after sub-bowman keratomileusis (SBK) for the correction of moderate and high myopia.

Retrospective case series.Sixty eight myopic eyes of 35 consecutive patients in Chongqing Medal Eye Institute from May to November 2011 were enrolled in this study.All patients were evaluated at 2 weeks,1 and 3 months postoperatively.The main measurements included visual acuity,corneal and total optical wavefront aberration,photopic and mesopic contrast sensitivity.

The median values of preoperative uncorrected central visual acuity (UCVA) and best corrected visual acuity (BCVA) were 0.05 and 1.00,respectively.The median value of postoperative UCVA was 1.20.There was no significant difference between the preoperative and postoperative anterior corneal total aberration (F=0.712,P>0.05).Compared with preoperative value (0.47±0.17) μm,the corneal high orders aberrations in 2 weeks after SBK (1.37±0.72) μm increased by 3 times.The total optical aberrations in 2 weeks after SBK (0.99±0.58) μm decreased to one-eighth of preoperative measurements (8.26±2.93) μm.Compared with preoperative value (0.30±0.12) μm,the total high order aberrations in 2 weeks after SBK (0.46±0.19) μm increased by 1.5 times.Although photopic and mesopic contrast sensitivity fluctuated mildly after SBK,the measurements did not decline significantly.Compared with preoperative data,mesopic contrast sensitivity at 3 months increased 0.294 (F=20.88,P<0.01) and 0.296 (F=13.64,P<0.01) at 12 and 18 c/d,respectively.

Patients could obtain good quality of vision at the early stage after SBK. (Chin J Ophthalmol,2013,49:416-421)

To investigate the differentiation and proliferation of the conjunctival epithelium and tear film function in pterygia.

It was a retrospective study.Fifteen patients (15 eyes) who underwent excision for pterygium were enrolled in this study.Immunostaining for K10,K14,K19,MUC5AC,K16,Ki67 and P63 was performed on the pterygial epithelium and normal conjunctival epithelium.Schirmer I test was performed,and the tear film break-up time (BUT) was evaluated just prior to and 6 months after surgery.Multi-factor regression analysis was assessed to observe if there is a correlation between pterygial growth and tear film function.

The average absorbency of K19 and MUC5AC immuno-staining all significantly changed (3727.86±2544.73 vs.25 528.00±12 901.06,2080.48±2340.17 vs.7182.51±3069.20,t=9.261,3.538,P<0.05),and increased in K10 and K14 in patients with pterygia compared with normal conjunctivae keratin (2017.51±2114.3 vs.0,6027.5±1058.32 vs.2123.28±1249.09,t=-6.151,P<0.05).Furthermore,pterygial epithelium showed activated proliferation,evidenced by significantly upregulated expression of K16,P63 and Ki67 compared to normal control.The Schirmer I test did not indicate any significant differences pre-and post-operatively.However,the BUT was signficantly prolonged 1 month post surgery compared to pre-surgery (t=-4.222,P<0.05).

This study indicates that abnormal epithelial differentiation and proliferation are present in pterygium,which is characterized by squamous metaplasia,accompanied with instability of tear film and normal basic tear secretion. (Chin J Ophthalmol,2013,49:422-427)

To investigate the characteristics of choroidal melanoma in contrastenhanced ultrasonography.

Case-control study.From October 2007 to December 2008,21 choroidal melanoma patients (21 eyes) were treated in Beijing Tongren Hospital,including 13 males and 8 females with average age at 57 years (ranged from 18 to 76 years).Fourteen cases (14 eyes) of choroidal hemangioma treated during the same period,including 9 males and 5 females,with average age at 51 years (ranged from 24 to 71 years) were selected for the comparison.All patients were examined with contrast-enhance ultrasound,the contrast agent (sulfur hexafluoride) was injected into elbow vein,continuous recording of contrast agent in the lesions was conducted from filling to subside stages.Sonoliver software was used to analyze the imaging process.Logistic regression was used to compare the data collected from choroidal melanoma and hemangioma to develop a differential diagnosis equation for the diagnosis of choroidal melanoma.

Contrast-enhanced ultrasonography in choroidal melanoma showed the following characteristics: the lesions were completely filled with the contrast reagent,the typical filling process began from the peripheral area to the center,filling defects were found in some cases,filling time in the melanoma was later than that in the normal tissues and faded early than that in the normal tissues.Quantitative analysis in choroidal melanoma lesions showed that the time to peak of contrast material[ (22.80±9.85) s] was less than that in the control group[ (29.57±24.76) s],maximum intensity[ (191.31±146.90) %] was greater than that in the control group[ (100.00±0.00) %];rising time[ (18.52±7.09) s] was less than that in the control group[ (26.45±21.83) s]and mean transit time[ (63.56±26.04) s]was less than that in the control group[ (149.87±182.68) s].The differences of maximum intensity and mean transit time between the melanoma and the controls were statistically significant (t=-2.848,2.197;P<0.01).Logistic regression equation using the maximum intensity and mean transit time parameters could distinguish choroidal melanoma and hemangioma with a sensitivity at 90.5% (19/21) and specificity at 12/14.

Contrast-enhanced ultrasonography is a new method for the diagnosis of malignant tumors in the eye.Contrast-enhanced ultrasonography combining with quantitative analysis can be helpful for the diagnosis and different diagnosis of choroidal melanoma. (Chin J Ophthalmol,2013,49:428-432)

To investigate the effect of doxycycline on the nucleolar organizing regions and a-smooth muscle actin expression in bovine corneal myofibroblasts in vitro and assess its contribution to ocular surface repair mechanisms.

Cell culture and identification: bovine corneal fibroblasts were cultured after the stroma was incubated in 1.0 and 2.0 g/L type I collagenase in two stages.Isolated cells were plated at mantaryay culture flask in 10% of BSA RPMI-1640.Vimentin and alpha-smooth muscle actin (α-SMA) organization were evaluated by immunocytochemistry.The cells staining positive for Vimentin andα-SMA indicated the presence of corneal myofibroblasts.Bovine corneal myofibroblasts were treated with different concentrations of doxycycline (10,20,40,60,80 mg/L),a bland control group and the dexamethasone group (120 mg/ L) were set up,each group had 30 cases.The argyrophilic nucleolar organizing regions (Ag NOR) staining and the immunohistochemistry forα-SMA were performed when the cells were treated for 24 hours and 48 hours.The AgNOR count (Ag-c),AgNOR area (Ag-a) and the expression ofα-SMA in the bovine corneal myofibroblasts among each experiment group and control group were compared using one-way ANOVA,further pairwise comparisons using Independent-Samples t test.

Cell culture techniques were successfully used to establish a method for the isolation and culture of bovine corneal myofibroblasts.Microscopic examination and immunohistochemical staining confirmed that the cells cultured were bovine corneal myofibroblasts.The Ag-c and Ag-a of bovine corneal myofibroblasts progressively decreased as the concentrations of doxycycline was increase.24 h:bland control group Ag-c was 6.40±0.6,60 mg/L doxycycline group Ag-c was 2.23±0.43;bland control group Ag-a was (34.80±2.36) μm²,60 mg/L doxycycline hormone group Ag-a was (19.91±2.15) μm².48 h:bland control group Ag-c was 7.27±0.6,60 mg/L doxycycline hormone group Ag-c was 2.80±0.76,bland control group Ag-a was (36.27±1.99) μm²,60 mg/ L doxycycline group Ag-a was (13.75±2.09) μm2.The differences were statistically significant:in the same time intervention (F_{Ag-c 24 h}=252.55,F_{Ag-a 24 h}=202.16,P<0.05,F_{Ag-c 48 h}=169.38,F_{Ag-a 48 h}=853.23,P<0.05),in the same concentrations intervention (t_Ag-c=6.98,t_Ag-a=11.62,P<0.05).And 60 mg/L of doxycycline had an obviously inhibitory action as 120 mg/L dexamethasone in the same treated hours (dexamethasone group Ag-a 24 h=30.56±3.66,dexamethasone group Ag-a 48 h=28.35±1.23),the differences were not statistically significant (t_Ag-a24h=1.182,P=0.242,t_Ag-a48h=0.21,P=0.832).As the concentrations investigated,doxycycline can inhibit the expression ofα-SMA in the bovine corneal myofibroblasts (189.90±7.48,140.20±7.79,113.20±8.98,98.00±3.50,85.50±4.99),the difference was statistically significant (F=761.79,P=0.00).While dexamethasone had no significant role in the expression ofα-SMA (bland control group was 225.10±6.74,the dexamethasone group was 228.50±7.12),and the statistically difference was not obvious (t=1.096,P=0.287).

As the concentrations of doxycycline was increased from 10 mg/L to 80 mg/L,the Ag NOR count and AgNOR area of bovine corneal myofibroblasts can be significantly reduced in vitro.Compared with dexamethasone,doxycycline significantly suppressed the expression ofα-SMA in bovine corneal myofibroblasts in a dose-dependent positive trend. (Chin J Ophthalmol,2013,49:)

To investigate the survival of SD rat retinal cells after irradiated with 460-480 nm wavelength blue light at three different irradiance.

Experimental study.Seventysix SD rats six weeks old were divided into control group (4 animals) and experimental groups (18 different subgroups) with 4 animals for each group.Healthy SD rats were exposed to the 460-480 nm blue light for 3 or 12 hours on three different irradiance of 0.6,1.5 and 10.0 W/m²respectively.After recovery in darkness for 4 hours,24 hours or 3 days,retinal tissue was collected after the eyes were enucleated.Hematoxylin-eosin staining was performed to evaluate the general anatomical changes of the rat retinal layers.Td T-mediated d UTP nick-end labeling was performed to detect apoptotic cells and immunofluorescence staining was conducted to illustrate the expression and location of related proteins in Müller cells.The number of ganglion cells was analyzed by one-way ANOVA.

No injury was observed in SD rat retina at the irradiance of 0.6 W/m2.Retinal cells were damaged with irradiance at 10.0 W/m²,which mainly affected photoreceptors and retinal pigment epithelial cells,while Müller cells of retinal inner nuclear layer were also involved.Apoptosis began after 4 hours of exposure and peaked at 24 hours.Moderate damage of retina was observed at the irradiance of 1.5 W/m²after 12 hours rather than 3 hours exposure.The number of ganglion cells was significantly different among the different groups 3 days after exposure.When the exposure time was 3 hours,the number of retinal ganglion cells under different irradiance at 0.0,0.6,1.5 and 10.0 W/ m²was respectively 41.42±0.17,40.58±0.50,40.92±0.32 and 22.83±0.79 (F=1305.86,P=0.000).When the exposure time was 12 hours,the number of retinal ganglion cells under different irradiance at 0.0,0.6,1.5 and 10.0 W/m²was respectively 41.42±0.17,40.83±0.69,41.08±0.17 and 22.75±0.83 (F=1095.78,P=0.000).The number of retinal ganglion cells showed significant decrease 3 days after exposure at the irradiance 10.0 W/m² (exposure time 3 h:t=52.32,P=0.000;exposure time 12 h:t=47.58,P=0.000).

The safe exposure time to SD rat retina layers is 12 hours for the blue light with wavelength 460-480 nm at the irradiance 0.6 W/m².And the safe exposure time descends to 3 hours at the irradiance 1.5 W/m². (Chin J Ophthalmol,2013,49:438-446)

As the leading cause of blindness,the type of surgery performed to remove cataracts has evolved from Intracapsular to Extracapsular and to phacoemulsification.Advantages of femtosecond laser include high instantaneous power,strong penetration,short pulse-duration and micro-precision present superior accuracy,predictability and safety to cataract surgery,while also minimizing injury to surrounding ocular tissue.It mainly assists in the procedures of anterior capsulotomy,lens fragmentation,clear corneal incision and limbal relaxing incision creation.However,compared to conventional phacoemulsification,problems such as the minimization of complications and difficulties in conducting peer-reviewed studies with a longer follow-up period and large sample,as well as coverage of added costs remain untracked.The purpose of this review is to outline the advantages and disadvantages as well as clinical value of this evolving technology compared to conventional phacoemulsification. (Chin J Ophthalmol,2013,49:464-467)

Cataract is the leading cause of blindness in the world.The use of certain drugs is one of the risk factors for lens opacities,such as glucocorticoids and chlorpromazine.We reviewed new studies regarding the relationship between cataract formation and drugs that have become more widely used in recent years,such as statins,anti-epileptic drugs,antidepresssants,tamoxifen,amiodarone,eltrombopag,isotretinoin,nifedipine and quetiapine.We hope this review could offer suggestions and reference for clinical doctors. (Chin J Ophthalmol,2013,49:468-471)

Congenital cataract is a major cause of treatable blindness in the pediatric population worldwide.Advances in microsurgical techniques have significantly increased the success rate of surgery.However,visual rehabilitation outcomes are not always satisfactory even after a successful surgery.Due to delayed surgery,irrational aphakic correction,and lack of amblyopic training,a large number of infants in China remain blind or low-visioned after cataract surgery.Appropriate timing of surgical intervention,rational surgical methodology as well as systematic optical correction and amblyopic training are critical for the prevention of blindness and low vision in congenital cataract. (Chin J Ophthalmol,2013,49:472-476)