Predictors of short-term outcomes related to central subfield foveal thickness after intravitreal bevacizumab for macular edema due to central retinal vein occlusion

AIM：To investigate the predictive factors for shortterm effects of intravitreal bevacizumab injections on central subfield foveal thickness（CSFT）in patients with macular edema（ME）secondary to central retinal vein occlusion（CRVO）.·METHODS：This was a retrospective study in 60 eyes treated with intravitreal bevacizumab injections for ME due to CRVO.Follow-up was three months.The Early Treatment Diabetic Retinopathy Study（ETDRS）score and CSFT measured by spectral-domain optical coherence tomography（SD-OCT）were used to observe the changes in best-corrected visual acuity（BCVA）.Baseline BCVA,CSFT,age,CRVO duration and the presence of cystoid macular edema（CME）or subretinal fluid（SRF）were analyzed as potential predictive factors of the effects of intravitreal bevacizumab injections.·R ESULTS：BCVA improved from 0.9 log MAR at baseline to 0.6 log MAR at 3mo,which was associated with a significant reduction in CSFT from 721μm to 392μm 3mo after injection.About 50%of CME cases and more than90%of SRF cases responded to treatment with a complete resolution at 3mo.Age（=0.036）and low baseline CSFT（=0.037）were associated with a good 3-month prognosis.Patients〉60 years old achieved better CME resolution（=0.031）and lower CSFT at 3mo（305μm 474μm,=0.003）.·CONCLUSION：Intravitreal bevacizumab significantly improved visual acuity and CSFT in patients with CRVO after 3mo.Older age and lower baseline CSFT were good predictors of short-term CSFT outcomes.The retinal thickness response to bevacizumab might depend on the resolution of CME rather than SRF.

Comparison of central macular thickness between two spectral-domain optical coherence tomography in elderly non-mydriatic eyes

AIM: To compare central macular thickness (CMT) measurements obtained by two spectral-domain optical coherence tomography (SD-OCT) exams, and to evaluate measurement reproducibility and agreement between these two exams, and to investigate the relationship between CMT and possible influencing factors such as age, sex, eye (OD/OS), and operators in elderly non-mydriatic eyes. METHODS: Seventy-two normal subjects were included. Every subject underwent CMT measurement twice using one of two SD-OCT (OSE-2000, Moptim, Shenzhen, China & 3-D OCT-1000, Topcon, Tokyo, Japan) instruments respectively where we randomly chose one eye in each patient for the test; these exams were performed by two operators over an hour period with a brief rest between sessions. Comparison of the OSE-2000 and 3-D OCT-1000 CMT measurements was based on paired- t test The mean difference between the CMT measurements was calculated. General linear model analyzed the relationships among eye (OD/OS), operator, sex, and CMT values using age as co-variant. All tests were considered statistically significant at P <0.05. The main outcome measures included CMT. RESULTS: When evaluated with general linear model analysis, CMT measurements were found to have high reproducibility across the two instruments between the two operators for the OSE-2000 single line scan and 3-D OCT-1000 macular scans (P=0.731; P=0.443). There was statistically significant difference in CMT values between the two instruments (P<0.001) and the mean difference was -46.83 mu m at 95% confidence limits (-49.15,-44.51). Age was positively correlated with CMT (beta coefficient =0.516, P=0.001; beta coefficient=0.453, P =0.009) and sex was correlated with CMT from the OSE-2000 (P=0.021) but not with the 3-D OCT-1000 (P=0.056). According to the actual thickness measurements, the CMT of the male was thicker than the female's but there was no statistical difference. There was interaction between sex and eye in OSE-2000 and not in 3-D OCT-1000 (P=0.02; P =0.374). No significant correlation was found between CMT and the influencing factor of eye in both of the instruments (P=0.884; P=0.492). CONCLUSION: Reproducibility of CMT measurement using the two SD-OCTs is excellent in normal eyes according to the operator factor analysis. OSE-2000 has a different posterior retinal boundary of CMT measurement, which results in the CMT value differences, compared with the 3-D OCT-1000. Age is positively correlated with CMT measurement while sex is correlated with CMT in the OSE-2000 but not in the 3-D OCT-1000 and eye (OD/OS) had no correlation with CMT values. Mydriatic drops may not be necessary for CMT measurement using high scan rate SD-OCT in normal eyes in dark room.

Comment on “Correlation between macular ganglion cell-inner plexiform layer thickness and visual acuity after resolution of the macular edema secondary to centralretinal vein occlusion”

Dear Editor,We would like to address several issues with the study of Kim et a". The study was retrospectively conducted with the existence of a selection bias attributable to inclusion of 2 completely different etiologic subgroups of patients with nonischemic central retinal vein occlusion (CRVO), namely, patients older than 50y, who usually have common systemic conditions such as hypertension and diabetes;and patients younger than 50y, in whom other mechanisms, such as the hyperviscosity syndrome or inflammatory condition, should be specifically considered.

Detection of macular ganglion cell complex loss and correlation with choroidal thickness in chronic and recurrent central serous chorioretinopathy

AIM:To investigate the association of ganglion cell complex thickness(GCCt),global loss volume percentage(GLV%),and focal loss volume percentage(FLV%)with structural and functional findings among patients with chronic central serous chorioretinopathy(CCSC)and recurrent central serous chorioretinopathy(RCSC)by optical coherence tomography(OCT).METHODS:Among 29 patients with monocular affected central serous chorioretinopathy(CSC),15 had CCSC,and 14 had RCSC.The GCCt,FLV%,GLV%,and subfoveal choroidal thickness(SFCT)and sublesional choroidal thickness(SLCT)values were determined using OCT,and the association of these characteristics with neural structure parameters,choroidal morphology,features and functional alterations were estimated for the CCSC and RCSC patients.RESULTS:In CCSC,the affected eyes had significantly lower GCCt values than the fellow eyes in the macular regions(all P<0.05),with the highest GCCt observed in the inferior area.A significant association was found between the GCCt in different regions and the change in best corrected visual acuity(BCVA;r=-0.696;-0.695;-0.694,P<0.05)in CCSC patients.A statistically significant moderate negative correlation indicated that long-term CCSC was associated with greater differences in the GCCt in different regions between affected and fellow eyes(r=-0.562;r=-0.556;r=0.525,P<0.05).Additionally,observation of thickened SFCT was associated with a worse FLV%(r=0.599;r=0.546,P<0.05)in both groups.Similarly,thickened SLCT was associated with FLV%in RCSC patients(r=0.544,P<0.05).CONCLUSION:The distribution and GCCt are associated with the duration and visual outcomes of CCSC,whereas there is no correlation among RCSC patients.FLV%may be instrumental in differentiating the various outer choroidal vessels(pachyvessels)in long-term CSC.These results suggest that neural structure parameters may aid in estimating and predicting the recovery of altered morphology and function in CCSC and RCSC patients.

Using choroidal thickness to detect myopic macular degeneration

AIM:To explore the usage of choroidal thickness measured by swept-source optical coherence tomography(SS-OCT)to detect myopic macular degeneration(MMD)in high myopic participants.METHODS:Participants with bilateral high myopia(≤−6 diopters)were recruited from a subset of the Guangzhou Zhongshan Ophthalmic Center-Brien Holden Vision Institute High Myopia Cohort Study.SS-OCT was performed to determine the choroidal thickness,and myopic maculopathy was graded by the International Meta-Analysis for Pathologic Myopia(META-PM)Classification.Presence of MMD was defined as META-PM category 2 or above.RESULTS:A total of 568 right eyes were included for analysis.Eyes with MMD(n=106,18.7%)were found to have older age,longer axial lengths(AL),higher myopic spherical equivalents(SE),and reduced choroidal thickness in each Early Treatment Diabetic Retinopathy Study(ETDRS)grid sector(P<0.001).The area under the receiver operating characteristic(ROC)curves(AUC)for subfoveal choroidal thickness(0.907)was greater than that of the model,including age,AL,and SE at 0.6249,0.8208,and 0.8205,respectively.The choroidal thickness of the inner and outer nasal sectors was the most accurate indicator of MMD(AUC of 0.928 and 0.923,respectively).An outer nasal sector choroidal thickness of less than 74μm demonstrated the highest odds of predicting MMD(OR=33.8).CONCLUSION:Choroidal thickness detects the presence of MMD with high agreement,particularly of the inner and outer nasal sectors of the posterior pole,which appears to be a biometric parameter more precise than age,AL,or SE.

Macular and peripapillary retinal nerve fiber layer thickness in children with hyperopic anisometropic amblyopia

AIM:To compare the retinal nerve fiber layer (RNFL) thickness and macular thickness in the amblyopic eye with that in the sound eye of children with hyperopic anisometropic amblyopia using optical coherence tomography (OCT). METHODS:A prospective, nonrandom, intraindividual comparative cohort study includes 72 children with hyperopic anisometropic amblyopia in a single center. Macular thickness, macular foveola thickness, and peripapillary RNFL thickness were compared between the amblyopia eyes and the contralateral sound eyes. ·RESULTS:There were 38 male and 34 female patients, with a mean age as 9.7 ±1.9 years (range, 5-16 years). Hyperopic was +3.62±1.16D (range +2.00D to +6.50D) in the amblyopic eyes, which was significantly higher in the control eyes with +0.76±0.90D (range 0D to +2.00D) (P 【 0.01). The mean peripapillary RNFL thickness was 113.9± 7.2μm and 109.2 ±6.9μm in the amblyopic eye and the normal eye, respectively, reaching statistical significance (P = 0.02). The mean macular foveola thickness was significantly thicker in the amblyopic eyes than the contralateral sound eyes (181.4±14.2μm vs 175.2±13.3μm, P 【0.01), but the 1mm, 3mm or 6mm macular thickness central macular thickness was not significantly different. Degree of anisometropia in the contralateral eyes was not significantly correlated with differences of peripapillary RNFL, macular foveola thickness or central macular thickness. CONCLUSION:Eyes with hyperopic anisometropic amblyopia are found thicker macular foveola and peripapillary RNFL than the contralateral eyes in children.

Foveal thickness reduction after anti-vascular endothelial growth factor treatment in chronic diabetic macular edema

AIM：To report foveal thickness reduction in eyes with resolution of macular edema and recovery of a foveal depression after one-year of anti-vascular endothelial growth factor（anti-VEGF） therapy for center-involving diabetic macular edema（DME）.METHODS：Foveal thickness was assessed with optical coherence tomography to determine the central subfield foveal thickness（CSFT） and macular volume in 42 eyes with DME（CSFT〉275 μm）. Evaluations also included measurement of best-corrected visual acuity（BCVA）, and were performed at baseline, and upon foveal depression recovery achieved after 12 monthly intravitreal injections of either 1.5 mg/0.06 mL bevacizumab（n=21） or 0.5 mg/0.05 mL ranibizumab（n=21）. Data was compared to 42 eyes of normally sighted, non-diabetic, healthy individuals with similar age, gender and race distributions.RESULTS：Mean baseline BCVA was 0.59±0.04 and 0.32± 0.03 log MAR（P〈0.001） after treatment and resolution of DME, with all, but 3 eyes, showing BCVA improvement. Mean CSFT before treatment was 422.0±20.0 μm, and after treatment, decreased to 241.6±4.6 μm（P〈0.001）, which is significantly thinner than CSFT found in control subjects（272.0±3.4 μm; P〈0.001）. Moreover, in 33/42 DM eyes（79%）, CSTF was thinner than the matched control eye. Macular volume showed comparable results, but with lower differences between groups（control：8.5±0.4 mm^3; DME：8.2±1.0 mm^3; P=0.0267）.CONCLUSION：DME eyes show significantly lower foveal thickness than matched controls after DME resolution achieved with one-year anti-VEGF therapy. Further investigation into the reasonsfor this presumable retinal atrophy using fluorescein angiography and functional parameters as well as establishing possible predictors is warranted. This finding should be considered during the treatment of DME.

Three-dimensional diabetic macular edema thickness maps based on fluid segmentation and fovea detection using deep learning

AIM: To explore a more accurate quantifying diagnosis method of diabetic macular edema(DME) by displaying detailed 3D morphometry beyond the gold-standard quantification indicator-central retinal thickness(CRT) and apply it in follow-up of DME patients.METHODS: Optical coherence tomography(OCT) scans of 229 eyes from 160 patients were collected.We manually annotated cystoid macular edema(CME), subretinal fluid(SRF) and fovea as ground truths.Deep convolution neural networks(DCNNs) were constructed including U-Net, sASPP, HRNetV2-W48, and HRNetV2-W48+Object-Contextual Representation(OCR) for fluid(CME+SRF) segmentation and fovea detection respectively, based on which the thickness maps of CME, SRF and retina were generated and divided by Early Treatment Diabetic Retinopathy Study(ETDRS) grid.RESULTS: In fluid segmentation, with the best DCNN constructed and loss function, the dice similarity coefficients(DSC) of segmentation reached 0.78(CME), 0.82(SRF), and 0.95(retina).In fovea detection, the average deviation between the predicted fovea and the ground truth reached 145.7±117.8 μm.The generated macular edema thickness maps are able to discover center-involved DME by intuitive morphometry and fluid volume, which is ignored by the traditional definition of CRT>250 μm.Thickness maps could also help to discover fluid above or below the fovea center ignored or underestimated by a single OCT B-scan.CONCLUSION: Compared to the traditional unidimensional indicator-CRT, 3D macular edema thickness maps are able to display more intuitive morphometry and detailed statistics of DME, supporting more accurate diagnoses and follow-up of DME patients.

The analysis of macular perimetry with octopus 900 in acute central serous chorioretinopathy

Background:To find the changes of macular perimetry(MP) and the correlations between MP and best correct visual acuity(BCVA) in different phases of the acute central serous chorioretinopathy(CSC).Methods:Twenty-one eyes with acute CSC and their fellow eyes were analysed retrospectively.MP at 2°,4°and BCVA in the active and resolved phase were collected and analyzed.The differences of these parameters in CSC eyes and fellow eyes were analyzed.Spearman correlation was used for analysis of correlation between MP and BCVA.Results:From 29 eyes with CSC analysed 27 eyes(93.10%) recovered to the previous VA.Compared with the active phase,MP at 2°,4° and BCVA were significantly improved in the resolved phase(P=0.000,0.000,0.000,respectively).MP at 2°,4° and BCVA of CSC eyes were significantly poor compared with the fellow eyes in the active phase(P=0.000,0.000,0.000,respectively).In the resolved phase there was no significant difference between the CSC eyes and fellow eyes(P=0.339,0.141,0.161,respectively).BCVA was shown to significantly correlate with MP at 2° in the active phase(ρ=-0.630,P<0.001).Conclusions:The acute CSC often had a good prognosis both in BCVA and MP.MP can provide an additional objective parameter to evaluate the retinal function changes at macula of acute CSC.

Intravitreal injection of bevacizumab alone or with triamcinolone acetonide for treatment of macular edema caused by central retinal vein occlusion

AIM: To compare the efficacy and safety of intravitreal bevacizumab alone versus bevacizumab combined with triamcinolone acetonide in eyes with macular edema caused by central retinal vein occlusion (CRVO) in Chinese patients. METHODS: Seventy-five eyes of 75 patients were enrolled in this prospective, randomized, consecutive study. Thirty-six patients in group 1 were treated with an intravitreal injection of bevacizumab (1.25mg/0.05mL), and 39 patients in group 2 were treated with intravitreal bevacizumab (1.25mg/0.05mL) combined with triamcinolone acetonide (2mg/0.05mL). The main outcomes of the mean best corrected visual acuity (BCVA), central retinal thickness (CRT), and intraocular pressure (IOP) were measured. RESULTS: In group 1, the mean BCVA improved from 37.78 +/- 6.14 (baseline) to 48.06 +/- 3.86, 46.48 +/- 4.77 and 44.18 +/- 5.78 at four, six and twelve weeks post-injection, respectively (P<0.01, P=0.03, P=0.04). In group 2, the mean BCVA improved from 35.92 +/- 6.20 (baseline) to 50.69 +/- 4.22, 48.76 +/- 5.59 and 45.70 +/- 6.56 at the same time points (P<0.01 each). However, there was no significant differences in the mean BCVA (F=0.043, P=0.836) and CRT (F=0.374, P=0.544) between these two groups. During the follow-up, five patients in group 1 and six patients in group 2 with high IOP were controlled with anti-glaucoma drugs. CONCLUSION: Intravitreal injection of bevacizumab alone or combined with triamcinolone acetonide has a short beneficial effect in Chinese patients with macular edema caused by CRVO, but there is no significant difference between the two groups.

Comparison of central corneal thickness measurements with three new optical devices and a standard ultrasonic pachymeter

AIM:To compare the RTVue spectral optical coherence tomography(SD-OCT),Sirius Scheimpflug-Placido topographer,Lenstar optical low coherence reflectometry(OLCR)and ultrasound pachymetry(USP)devices in terms of their agreement and repeatability of measuring central corneal thickness(CCT).METHODS:In this prospective study,50 eyes of 50patients were included.Three repeated measures were obtained using SD-OCT,Scheimpflug-Placido topographer and USP and five measurements were determined with the OLCR.Bland-Altman plots were used to assess agreement among the instruments,and 95%limits of agreement(LoA)for each comparison were calculated.Intra-examiner repeatability was assessed using intraclass correlation coefficients(ICCs).RESULTS:The mean CCT by SD-OCT,ScheimpflugPlacido topographer,OLCR,and USP were 525.90±34.08μm,525.92±34.10μm,530.30±35.62μm,and543.50±37.11μm respectively.All 4 modalities of CCT measurements correlated closely with each other,with Pearson correlation coefficients ranging from 0.977 to0.995.The mean differences(and upper/lower LoA)for CCT measurements were-0.05±6.77μm(13.3/-13.3)between SD-OCT and Scheimpflug-Placido topographer,4.38±3.79μm(11.8/-3.1)between OLCR and SD-OCT,4.38±6.03μm(16.2/-7.5)between OLCR and ScheimpflugPlacido topographer,13.20±6.46μm(25.9/0.5)between USP and OLCR,17.59±6.76μm(30.8/4.3)between USP and SD-OCT,and 17.58±8.13μm(33.5/1.6)between USP and Scheimpflug-Placido topographer.Intra-examiner repeatability was excellent for all devices with ICCs】0.98.CONCLUSION:For most practical purposes,CCT measurements with the RTVue,Sirius and Lenstar can be used interchangeably.Although highly correlated,CCTmeasurement differences between USP and these 3optical instruments can be significant depending on the clinical situation.

Distribution of central corneal thickness and intraocular pressure in emmetropic eyes of healthy children of Palestine: a representative cross-sectional study

AIM: To determine the distributions of central corneal thickness(CCT) and intraocular pressure(IOP) in emmetropic eyes of healthy children of Palestine.METHODS: This representative cross sectional study included a total of 1156 eyes from 578 healthy school children aged 7-15 y. Inclusion criteria included emmetropia, no previous history of ocular or systemic diseases, no previous history of contact lens use, and the availability of both eyes. CCT and IOP were measured using ultrasound pachymeter and Goldmann applanation tonometer, respectively. The relationship of the results with age and gender was investigated.RESULTS: The mean age of school children was 11.13±2.8 y. Mean CCT was 542.2±37.4 and 544.3±39.2 μm for right and left eyes, respectively. Mean IOP was 12.5±2.2 and 12.3±2.2 mm Hg for right and left eyes, respectively. A positive correlation was observed between CCT and IOP of the right eye(P<0.001, R=0.358) and CCT and IOP of the left eye(P<0.001, R=0.324). No significant differences were observed in CCT and IOP due to age or gender(P>0.05). There were significant differences in mean CCT and IOP between right and left eyes(P=0.004, P=0.001, respectively).CONCLUSION: A population profile of CCT and IOP is established in Palestinian children for the first time. Mean CCT is comparable to some studies but differ from others. Mean IOP is considerably lower than that of majority children of other ethnic groups. Intereye difference of more than 36 μm in CCT, and 5 mm Hg in IOP should prompt evaluation for potential ocular disorders.

Changes of corneal central thickness of aphakia following congenital cataract surgery under the first six months of life

AIM: To observe the central corneal thickness (CCT) changes in infants and young children who had been undergone bilateral congenital cataract surgery, and to compare the changes with normal control group which was selected from healthy population. METHODS: A cross section case-control study contained 28 cases (56 eyes) of bilateral aphakia (aphakic group) due to congenital cataract surgery combining with posterior continuous curvilinear capsulorhexis and with anterior vitrectomy during 2-6 months after birth. Fourteen children (28 eyes) of age-sex matched with the aphalic group were selected as normal control group. CCT and intraocular pressure (TOP) were measured postoperatively and the results were compared between groups. RESULTS: The mean CCT was 653.5 +/- 82.4 mu m in the aphakic group and 579.6 +/- 39.2 mu m in the control group, with a significant difference (P=0.000). The mean value of TOP in aphakic group (22.0 +/- 1.6mmHg) was greater than that of control group (16.9 +/- 2.1mmHg), P=0.023. There was a negative correlation between age and CCT in normal control group (r=-0.531, P=0.026), and there was no correlation in bilateral aphakia group (r=-0.324, P=0.165). CONCLUSION: Aphakic children due to congenital cataract surgery have a greater CCT than normal children. It is necessary to consider CCT in evaluating IOP for children after congenital cataract surgery.

Changes in intraocular pressure and central corneal thickness during pregnancy:a systematic review and Meta-analysis

AIM：To conduct a Meta-analysis for investigating the variations in intraocular pressure（IOP）and central corneal thickness（CCT）during normal pregnancy.METHODS：We searched for clinical trials published up to November 2015 without language or region restrictions in Pub Med,EMBASE,Web of Science,the Cochrane Central Register of Controlled Trials,Ovid,EBSCO,Elsevier,the Chinese Biomedicine Database,Wan Fang,CNKI,CQVIP and Google Scholar.Studies of the ocular changes observed in pregnant women were selected.The main outcomes were assessed by changes in IOP and CCT.RESULTS：Fifteen studies were included.In subgroup analyses,IOP was significantly decreased during the second MD=-1.53,95%CI（-2.19,-0.87）;P〈0.00001,and third MD=-2.91,95%CI（-3.74,-2.08）;P〈0.00001 trimesters of pregnancy.CCT was increased during the second MD=10.12,95%CI（2.01,18.22）;P=0.01,trimester of pregnancy;moreover,during the third trimester of pregnancy,the CCT displayed an increasing trend,but the difference was not significant MD=5.98,95%CI（-1.11,13.07）;P=0.1.CONCLUSION：A decrease in IOP is accompanied by an increase in CCT in the second and third trimesters of a normal pregnancy in women.

Corneal endothelial cell density and morphology and central corneal thickness in Guangxi Maonan and Han adolescent students of China

AIM: To investigate the corneal endothelial cell density and morphology and central corneal thickness in the Guangxi Maonan and Han adolescent students of China.METHODS: Noncontact specular microscope(Topcon SP3000 P, Tokyo, Japan) was performed in 133 adolescent students of Maonan nationality(M:F 54:79)and 105 adolescent students of Han nationality(M:F 50:55),5 to 20 y of age, who were randomly selected from 3schools in Huanjiang Maonan Autonomous County of Guangxi Zhuang Autonomous Region of China.Parameters studied included endothelial cell density,mean cell area, coefficient of variation in cell size,percentage hexagonality and central corneal thickness. RESULTS: Endothelial cell density, mean cell area,coefficient of variation in cell size, percentage hexagonality and central corneal thickness in the study population were(2969.50 ±253.93) cells/mm2,(339.23 ±29.44) μm2,(29.96 ±4.07) %,(64.58 ±9.41) % and(523.71 ±32.82) μm in Maonan and(2998.26 ±262.65) cells/mm2,(336.11±30.07) μm2,(29.89±5.03) %,(64.91±11.64) % and(524.39 ±33.15) μm in Han, respectively. No significant differences were observed in endothelial cell density,mean cell area, coefficient of variation in cell size,percentage hexagonality and central corneal thickness between Maonan and Han(P =0.615, 0.659, 0.528, 0.551,0.999). In Maonan and Han, we found age was negatively correlated with endothelial cell density and percentagehexagonality and positively correlated with mean cell area and coefficient of variation in cell size. Negative correlation was also found between central corneal thickness and age in Han, whereas no correlation was found in Maonan. CONCLUSION: There were no differences between Maonan and Han in corneal endothelial cell density and morphology and central corneal thickness. In these two nationalities, there were statistically significant decrease in endothelial cell density and percentage hexagonality with increasing age and statistically significant increase in cell area and coefficient of variation in cell size with increasing age. Central corneal thinned with increasing age in Han, whereas difference did not attain statistical significance in Maonan.

Analysis of macular microvasculature and thickness after ICL implantation in patients with myopia using optical coherence tomography

AIM:To investigate changes in macular vessels and thickness in myopic eyes after intraocular collamer lens(ICL)implantation using quantitative optical coherence tomography angiography(OCTA).METHODS:This retrospective included 73 myopic eyes of 73 patients(average age,27.53±6.16 y)who underwent ICL implantation(28 eyes were Toric ICL).Axial length(AL),uncorrected visual acuity(UCVA),refractive dioptre(RD),intraocular pressure(IOP)and OCTA were measured and compared with before and 1 wk,1,and 3 mo after surgery.OCTA was used to image vessel density(VD)and skeleton density(SD)in both the superficial(SCP)and deep capillary plexus(DCP).Central retinal thickness(CRT)and ganglion cellinner plexiform layer thickness(GCT)were also measured.Changes between pre-and postoperative measurements were analysed by repeated measures analysis of variance.RESULTS:Compared with preoperative data,postoperative data on UCVA revealed significant improvements in all patients(P<0.05).However,there was no significant difference in IOP.After the operation,CRT and GCT exhibited significant changes(P<0.05).Among these measures,CRT was significantly higher at one and three months postoperative(all P<0.01).GCT was significantly higher at 1 wk,1,and 3 mo postoperative(all P<0.01).Changes in VD and SD were nonsignificant in both the SCP and DCP.There was no difference in postoperative changes between the ICL and Toric ICL groups.CONCLUSION:ICL and Toric ICL implantation both have good efficacy and safety for myopic eyes,but macular area changes that occur after surgery need attention.

Characteristics of central visual field defect after macular hole surgery

AIM: To investigate the characteristics of postoperative central visual field defect(cVFD) in patients with macular hole(MH).METHODS: Eighteen eyes from 18 MH patients were involved in this retrospective study which reviewed square root of loss variance(sLV) and mean defect(MD) of the visual field test in all subjects. The relationship between cVFD and MH stage, as well as the postoperative ellipsoid zone disruption were evaluated using Spearman's correlation test. RESULTS: Our analysis determined Spearman coefficient is 0.705 for the correlation between sLV and MH stage(P<0.01), 0.877 for the correlation between sLV and postoperative ellipsoid zone disruption(P<0.01) and 0.721 for the correlation between MD and postoperative ellipsoid zone disruption(P<0.01). A significant relationship was also detected between postoperative ellipsoid zone disruption and MH stage(r=0.470, P<0.05). Univariate regression analysis indicated that sLV and MD were associated with postoperative ellipsoid zone disruption(P<0.01, P<0.01, respectively). CONCLUSION: Postoperative cVFD is highly correlated with MH stage and postoperative ellipsoid zone disruption in patients with MH.

Image registration of the human accommodating eye demonstrates equivalent increases in lens equatorial radius and central thickness

AIM: To compare the results of in vivo human high resolution image registration studies of the eye during accommodation to the predictions of mathematical and finite element models of accommodation. METHODS: Data from published high quality image registration studies of pilocarpine induced accommodative changes of equatorial lens radius(ELR) and central lens thickness(CLT) were statistically analyzed. RESULTS: The mean changes in ELR and CLT were 6.76 μm/diopter and 6.51 μm/diopter, respectively. The linear regressions, reflecting the association between ELR and accommodative amplitude(AAELR) was: slope=6.58 μm/diopter, r^2=0.98, P<0.0001 and between CLT and AACLT was: slope=6.75 μm/diopter, r^2=0.83, P<0.001. On the basis of these relationships, the CLT slope and the AAELR were used to predict the measured change in ELR(ELRpredicted). There was no statistical difference between ELRpredicted and the measured ELR as demonstrated by a Student's paired t-test: P=0.96 and linear regression analysis: slope=0.97, r^2=0.98, P<0.00001.CONCLUSION: Image registration with invariant positional references demonstrates that ELR and CLT equivalently minimally increase ~7.0 μm/diopter during accommodation. The small equivalent increases in ELRand CLT are associated with a large accommodative amplitude. These findings are consistent with the predictions of mathematical and finite element models that specified the stiffness of the lens nucleus is the same or greater than the lens cortex and that accommodation involves a small force(<5 g).

Central corneal thickness measurements in premature infants

AIM:To evaluate the central corneal thickness(CCT)measurements of premature infantsMETHODS:The premature infants who were born between 25-34wk of gestational age(GA)were retrieved for the study.All CCT measurements were performed within the first 2d of their life under topical anesthesia by using an ultrasonic pachymeter.RESULTS:The mean CCT of 200 eyes was 647.79±63.94μm.The mean CCT of the right and left eyes were similar(647.30±64.72μm and 648.29±63.47μm consecutively).The mean CCT of the girls was 642.08±54.89μm and the boys was 653.07±71.14μm,with no statistically significant difference(P】0.05).But there was a negative correlation of the CCT with GA and birth weight(BW)(P【0.01).CONCLUSION:The CCT values of premature babies were negatively correlated with GA and BW.

Macular thickness as a predictor of loss of visual sensitivity in ethambutol-induced optic neuropathy

Ethambutol is a common cause of drug-related optic neuropathy.Prediction of the onset of ethambutol-induced optic neuropathy and consequent drug withdrawal may be an effective method to stop visual loss.Previous studies have shown that structural injury to the optic nerve occurred earlier than the damage to visual function.Therefore,we decided to detect structural biomarkers marking visual field loss in early stage ethambutol-induced optic neuropathy.The thickness of peripapillary retinal nerve fiber layer,macular thickness and visual sensitivity loss would be observed in 11 ethambutol-induced optic neuropathy patients（22 eyes） using optical coherence tomography.Twenty-four healthy age-and sex-matched participants（48 eyes） were used as controls.Results demonstrated that the temporal peripapillary retinal nerve fiber layer thickness and average macular thickness were thinner in patients with ethambutol-induced optic neuropathy compared with healthy controls.The average macular thickness was strongly positively correlated with central visual sensitivity loss（r2=0.878,P=0.000）.These findings suggest that optical coherence tomography can be used to efficiently screen patients.Macular thickness loss could be a potential factor for predicting the onset of ethambutol-induced optic neuropathy.