Parallel Spectral-Domain Optical Coherence Tomography for Non-Scattering Object Imaging

The parallel spectral-domain optical coherence tomography（PSDOCT） is described for highspeed optical coherence tomography（OCT） without lateral scanning. In this setup, the self-elimination of auto-correlation（AC） interference algorithm was used for eradicating the AC interference and ghost images. However, when performed in free space OCT, this algorithm still generated a weak DC component. The algorithm was improved by adding the background intensity part to compensate for the mutual interference between object and reference arms. The results demonstrate that the DC component can be eradicated. Compared with conventional QCT and complex Fourier-domain optical coherence to- mography, the advantages of PSDOCT with the improved algorithm in free space are that it has no moving parts to generate consecutive phase shift, the structure of the object can be reconstructed immediately and automatically, and the speed is approximately 16 times faster than those of the other two in the same case.

Spectral-domain optical coherence tomography dynamic changes and steroid response in multiple evanescent white dot syndrome

Dear Editor,Multiple evanescent white dot syndrome （MEWDS） was first described in 1984 as a rare, acute, unilateral,multifocal retinochoroidal disorder, typically affecting young myopic women. Previous studies with fluorescein angiography （FA） and electrophysiology suggested that MEWDS to be a disease in the retinal pigment epithelium （RPE） or outer retina, while recent studies with spectral- domain optical coherence tomography （SD-OCT） suggested it may be an outer retinal disease due to observation of hyperreflective material in outer retina and subtle disruptionsof the ellipsoid zone without RPE disruption.

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.

1310 nm Source Spectral-Domain Optical Coherence Tomography for Chinese Pigment and Jadeite Research

Optical Coherence Tomography (OCT) technique is a nondestructive optical detection technology based on low-coherence interferometer and it has become an attractive cultural heritage research method. A 1310 nm source spectral-domain optical coherence tomography (SD-OCT) system based on optical fiber Michelson interferometer and optical spectrum analyzer is proposed and demonstrated for Chinese cultural heritage research. The cross-section OCT images of Chinese pigment samples and jadeite samples can provide a lot of valuable microstructure information for the Chinese cultural heritage research and identification works.

Renal function and choroidal thickness using swept-source optical coherence tomography in diabetic patients

AIM: To assess the relationship between choroidal thickness and renal function in diabetic patients. METHODS: Cross-sectional retrospective clinical study of 42 eyes of 21 ocular treatment-na?ve diabetic patients. Demographic data included: age, sex, type and course of diabetes. Ocular data included: severity of diabetic retinopathy;retinal thickness at the central macular region, as well as choroidal thickness at the central and paracentral quadrants, using automatically generated maps by swept-source optical coherence tomography;presence of cystic macular edema;and ocular axial length(AXL). Lab-test parameters included: glycated hemoglobin(HbA1c), albuminuria, albumin/creatinine ratio in urine, and glomerular filtration rate. RESULTS: A significant negative correlation was mainly observed between several choroidal thicknesses, age(P<0.020) and ocular AXL(P<0.030). On the contrary, a significant positive correlation was found between all choroidal thicknesses, HbA1 c(P<0.035) and albuminuria(P<0.040). CONCLUSION: Choroidal thickness can represent an additional tool to help clinicians predicting the renal status in ocular treatment-na?ve diabetic patients.

Artificial intelligence for the detection of glaucoma with SD-OCT images:a systematic review and Meta-analysis

●AIM:To quantify the performance of artificial intelligence(AI)in detecting glaucoma with spectral-domain optical coherence tomography(SD-OCT)images.●METHODS:Electronic databases including PubMed,Embase,Scopus,ScienceDirect,ProQuest and Cochrane Library were searched before May 31,2023 which adopted AI for glaucoma detection with SD-OCT images.All pieces of the literature were screened and extracted by two investigators.Meta-analysis,Meta-regression,subgroup,and publication of bias were conducted by Stata16.0.The risk of bias assessment was performed in Revman5.4 using the QUADAS-2 tool.●RESULTS:Twenty studies and 51 models were selected for systematic review and Meta-analysis.The pooled sensitivity and specificity were 0.91(95%CI:0.86–0.94,I2=94.67%),0.90(95%CI:0.87–0.92,I2=89.24%).The pooled positive likelihood ratio(PLR)and negative likelihood ratio(NLR)were 8.79(95%CI:6.93–11.15,I2=89.31%)and 0.11(95%CI:0.07–0.16,I2=95.25%).The pooled diagnostic odds ratio(DOR)and area under curve(AUC)were 83.58(95%CI:47.15–148.15,I2=100%)and 0.95(95%CI:0.93–0.97).There was no threshold effect(Spearman correlation coefficient=0.22,P>0.05).●CONCLUSION:There is a high accuracy for the detection of glaucoma with AI with SD-OCT images.The application of AI-based algorithms allows together with“doctor+artificial intelligence”to improve the diagnosis of glaucoma.

Clinical characteristics of peripapillary hyperreflective ovoid mass-like structures in myopic children

AIM:To describe the characteristics of peripapillary hyperreflective ovoid mass-like structure(PHOMS)in myopic children and to investigate factors associated with PHOMS.METHODS:This retrospective observational study included 101 eyes of 101 children(age≤17y)with myopia.All included patients underwent comprehensive clinical examination.Optic nerve canal parameters,including disc diameter,optic nerve head(ONH)tilt angle,and border tissue angle were measured using serial enhanced-depth imaging spectral-domain optical coherence tomography(EDI-OCT).Based on the optic disc drusen consortium’s definition of PHOMS,eyes were classified as PHOMS group and non-PHOMS group.PHOMS was categorized according to height.RESULTS:Sixty-seven(66.3%)eyes were found with PHOMS.Small PHOMS could only be detected by optical coherence tomography(OCT).Medium PHOMS could be seen with blurred optic disc borders corresponding to OCT.The most frequent location of PHOMS was at the nasosuperior(91%,61 of 67 eyes)to ONH disc.The axial length and spherical equivalent were more myopic in the PHOMS group than in the non-PHOMS group(both P<0.001).ONH tilt angle was also significantly greater in PHOMS group than in non-PHOMS group[8.90(7.16-10.54)vs 3.93(3.09-5.25),P<0.001].Border tissue angle was significantly smaller in PHOMS group than in non-PHOMS group[29.70(20.90-43.81)vs 45.62(35.18-60.45),P<0.001].In the multivariable analysis,spherical equivalent(OR=3.246,95%CI=1.209-8.718,P=0.019)and ONH tilt angle(OR=3.275,95%CI=1.422-7.542,P=0.005)were significantly correlated with PHOMS.There was no disc diameter associated with PHOMS.In the linear regression analysis,border tissue angle was negatively associated with PHOMS height(β=-2.227,P<0.001).CONCLUSION:PHOMS is associated with optic disc tilt and optic disc nasal shift in myopia.Disc diameter is not a risk factor for PHOMS.The changes in ONH caused by axial elongation facilitated an understanding of the mechanism of PHOMS.

Visual field defects and retinal nerve fiber layer damage in buried optic disc drusen: a new insight

AIM: To assess the association between buried optic disc drusen(BODD) location using spectral-domain optical coherence tomography(SD-OCT) and the location of associated visual field defects(VFD) using the Garway-Heath mapping.METHODS: This monocentric retrospective crosssectional study was led at the authors’ institution. Adult patients diagnosed with BODD who had complete records with a reliable Humphrey? 24-2 visual field, macular, and papillary OCT were enrolled. Fisher’s exact test was used to measure the association between BODD location and VFD distribution according to Garway-Heath’s mapping.RESULTS: Totally 20 eyes of 15 patients were included(60% females). The median age(interquartile range) was 63(43)y and the median best corrected visual acuity(BCVA) was-0.08(0.08) log MAR. BODD were mostly located in zones A, E, and F. The minimal rim width(MRW) was globally preserved. The retinal nerve fiber layer(RNFL) was predominantly altered in zones D, E, and F. There was a significant correlation between BODD location and that of RNFL alterations in zones D(P=0.03) and E(P=0.025);Moreover, the presence of BODD in the E zone was significantly related to damaged RNFL in the neighbouring sectors D and F(P=0.012;P=0.02 respectively). Sixty-three percent(12/19) of visual fields were abnormal and there was a significant match(Phi=0.7, P=0.009) between drusen location and VFD only in zone D.CONCLUSION: BODD do not only affect young patients and can be more harmful than usually expected, as we found VFD in 63% of cases. There is a correspondence between BODD location, RNFL damage, and VFD distributions. The presence of BODD induces the overestimation of MRW,thereby disrupting its sensitivity as an early indicator of ganglion fibers damage.

Analysis of choroidal morphology and comparison of imaging findings of subtypes of polypoidal choroidal vasculopathy:a new classification system

AIM:To classify polypoidal choroidal vasculopathy(PCV)into 2 subtypes based on the subfoveal choroidal thickness(SFCT)and to further evaluate their multimodal image features.METHODS:A retrospective observational case series study.Sixty-four eyes of 64 patients with PCV were enrolled and classified into 2 groups based on SFCT(thick-choroid group/thin-choroid group).Then further analyze the spectrum domain optical coherence tomography(SD-OCT)and indocyanine green angiography(ICGA)differences of the two subtypes.Imaging analysis included measurement of SFCT,maximum vascular diameter ratio(MVDR),choroidal vascularity index(CVI),central macular thickness(CMT),and the presence of pigment epithelial detachment(PED)on SD-OCT.Polypoidal lesions(polyps)number,branching vascular network(BVN)area,greatest linear dimension(GLD),and the choroidal vascular hyperpermeability(CVH)were analyzed by ICGA.RESULTS:The distribution of SFCT was bimodal with two peaks at 195 and 285μm,and a trough at 225μm.The 225μm was taken as the cutoff point for the following classification of thick/thin choroid groups.The PCV eyes in the thick-choroid group presented with greater MVDR,CVI within 3 and 6 mm of the fovea,but lower CMT,less PED,small PED diameters on SD-OCT scans,and fewer polyps,smaller BVN and GLD,but more frequency of CVH on ICGA.CONCLUSION:The SFCT at 225μm can be used as a readily available indicator for the classification of PCV subtypes.The thick-choroid group presents much apparent enlargement of the choroidal layer and vasculature expansion,which indicates different pathogenesis of the two subtypes.

Disorganization of the retinal inner layers as a prognostic factor in eyes with central retinal artery occlusion

AIM: To evaluate baseline foveal disorganisation of retinal inner layers(DRIL) as a prognostic factor in eyes with central retinal artery occlusion(CRAO). METHODS: Twenty-eight CRAO patients who were followed-up between 2010 and 2016 were retrospectively investigated. Demographic characteristics and detailed ophthalmological examination findings of all patients were recorded. Macular thicknesses(MTs) from 5 separate spots and DRIL were measured with spectral-domain optic coherence tomography(SD-OCT). Correlations between DRIL score and logMAR converted visual acuity(VA), change in VA, patient reference time(RT), number of hyperbaric oxygen therapy(HBOT) sessions, MT and MT change were investigated.RESULTS: There was a positive correlation between the DRIL score and the final VA(r=0.787) and a negative correlation with the change in VA(r=-0.763). The RT and MT were closely related to the DRIL score. A negative correlation was found between the number of HBOT sessions and the DRIL score(r=-0.341).CONCLUSION: The DRIL score is a parameter assessed by SD-OCT, which can provide us reliable information regarding the prognosis of visual functions and response to the treatment for CRAO patients at acute phase.

Evaluation of outer retinal tubulations in diabetic macular edema underwent anti-VEGF treatment

AIM: To investigate the incidence and subsequent changes of outer retinal tubulations(ORTs) in diabetic macular edema(DME) underwent anti-vascular endothelial growth factor(VEGF) therapy, and to assess the possibility of ORT as a biomarker of DME severity or response to anti-VEGF therapy.METHODS: This retrospective and descriptive study included a total of 228 patients(435 eyes) with DME and treated with intravitreal anti-VEGF agents between March 2016 and January 2018. Patients were divided into 2 groups according to the presence of ORTs. High-resolution spectral-domain optical coherence tomography(SD-OCT) images acquired by vertical and horizontal scans and over consecutive visits were analyzed. The evolution of ORT over time, type of fluid and subfoveal photoreceptor integrity on OCT imaging was also assessed. RESULTS: ORTs were identified in 108 eyes of 435 eyes with an overall incidence rate of 24.83% at baseline. ORTs were prone to locate adjacent to the lesions of exudation and/or cystoid edema and possibly situated in outer nuclear layer(ONL), outer plexiform layer(OPL) and/or inner nuclear layer(INL) in eyes with DME. The formation process of ORT led to focal downward displacement of OPL and INL toward RPE near the lesion. During the follow up, 45 eyes had steady ORTs and 63 eyes had dynamic variants in ORTs, including disappearance, reappearance, collapse, diminution, and enlargement. There were higher proportion of closed ORTs and fewer proportion of forming ORTs in eyes with steady ORTs, which showed a statistically significance when compared with eyeswith variant ORTs(P=0.006, P=0.017, respectively). The eyes without ORTs had significantly better final best corrected visual acuity(BCVA) and more BCVA change than those eyes with ORTs in DME patients after antiVEGF therapy(P=0.023, P=0.009, respectively). The disruption of subfoveal photoreceptor integrity in eyes with ORTs was more serious than that in eyes without ORTs(P=0.013). The proportion of stable vision in eyes with ORTs was significantly higher than that in eyes without ORTs, showing statistical significance(P=0.016). ORTs were associated with worse visual prognosis due to damage of the subfoveal photoreceptor integrity. CONCLUSION: ORTs have a high incidence and changes over time in DME with anti-VEGF treatment and may be located at various retinal layers. Persistent ORT can be as a negative biomarker of outcome of DME.

Long term follow-up of a family with GUCY2D dominant cone dystrophy

AIM: To describe long term follow-up in a family with GUCY2D dominant cone dystrophy. METHODS: Optical coherence tomography scans and fundus autofluorescence images were obtained. Flash and pattern electroretinograms(ERGs) and occipital pattern reversal visual evoked potentials were recorded. RESULTS: Two members of the same family(father and son) were identified to have the heterozygous R838 C mutation in the GUCY2D gene. The father presented at the age of 45 with bilateral bull’s eye maculopathy and temporal disc pallor. Over 13 y of serial follow up visits, the bull’s eye maculopathy progressed gradually into macular atrophy. Electrophysiological tests were significantly degraded suggesting poor macular function. Spectraldomain optical coherence tomography(SD-OCT) scans showed progressive loss and disruption of the ellipsoid layer at the foveal level. His son presented at the age of 16 with bilateral granular retinal pigment epithelial changes in both maculae. Electrophysiological testing was initially borderline normal but has gradually deteriorated to show reduced cone ERGs and macula function. SD-OCT demonstrated gradual macular thinning and atrophy bilaterally. Unlike his father, there was no disruption of the ellipsoid layer.CONCLUSION: Both family members exhibited gradual changes in their fundi, electrophysiological testing and multimodal imaging. Changes were milder than those observed in other mutations of the same gene.

Importance of 3-D image reconstruction of spectraldomain OCT on outcome of grid laser photocoagulation for diffuse diabetic macular edema

AIM:To present the outcome of modified grid laser photocoagulation(GLP)in diffuse diabetic macular edema(DDME)in eyes without extrafoveal and/or vitreofoveal traction.METHODS:Inclusion criteria for the retrospective study were DDME eyes of patients with typeⅡdiabetes mellitus that had≥4 months of follow-up following GLP.Only one eye per patient was analyzed.Using 3-D spectral-domain optical coherence tomography(3-D SDOCT),eyes that had either extrafoveal or vitreofoveal traction,or had been previously treated by an intravitreal medication(s)were excluded.Treated DDME eyes were divided into 4 groups:A)"Classic"DDME that involved the central macula;B)edema did not involve the macular center;C)eyes associated with central epiretinal membrane(ERM);D)DDME that was associated with macular capillary dropout≥2 disc-diameter(DD).RESULTS:GLP outcome in 35 DDME eyes after 4-24(mean,13.1±6.9)months was as follows:Group A)18eyes with"classic"DDME.Following one or 2(mean,1.2)GLP treatments,best-corrected visual acuity(BCVA)improved by 1-2 Snellen lines in 44.4%(8/18)of eyes,and worsened by 1 line in 11.1%(2/18).Central macular thickness(CMT)improved by 7%-49%(mean,26.6%)in77.8%(14/18)of eyes.Causes of CMT worsening(n=4)were commonly explainable,predominantly(n=3)associated with emergence of extrafoveal traction,5-9months post-GLP.Group B)GLP(s)in DDME that did not involve the macular center(n=6)resulted in improved BCVA by 1-2 lines in 2 eyes.However,the central macula became involved in the edema process after the GLP in 3(50%)eyes,associated with an emergence of extrafoveal traction in one of these eyes 4months following the GLP.Group C)GLP failed in all 5eyes associated with central ERM.Group D)GLP was of partial benefit in 2 of 6 treated eyes with macular capillary dropout≥2DD.CONCLUSION:Eyes with DDME that involved the macular center were found to achieve favourable outcomes after GLP(s)during mid-term follow-up,unless complicated pre-GLP or post-GLP by vltreoretinal interface abnormalities,often extrafoveal traction or ERM,or by capillary dropout≥2DD.Prospective studies with larger cohorts are required.

Artificial intelligence for assessment of Stargardt macular atrophy

Stargardt disease(also known as juvenile macular degeneration or Stargardt macular degeneration)is an inherited disorder of the retina,which can occur in the eyes of children and young adults.It is the most prevalent form of juvenile-onset macular dystrophy,causing progressive(and often severe)vision loss.Images with Stargardt disease are characterized by the appearance of flecks in early and intermediate stages,and the appearance of atrophy,due to cells wasting away and dying,in the advanced stage.The primary measure of late-stage Stargardt disease is the appearance of atrophy.Fundus autofluorescence is a widely available two-dimensional imaging technique,which can aid in the diagnosis of the disease.Spectral-domain optical coherence tomography,in contrast,provides three-dimensional visualization of the retinal microstructure,thereby allowing the status of the individual retinal layers.Stargardt disease may cause various levels of disruption to the photoreceptor segments as well as other outer retinal layers.In recent years,there has been an exponential growth in the number of applications utilizing artificial intelligence for help with processing such diseases,heavily fueled by the amazing successes in image recognition using deep learning.This review regarding artificial intelligence deep learning approaches for the Stargardt atrophy screening and segmentation on fundus autofluorescence images is first provided,followed by a review of the automated retinal layer segmentation with atrophic-appearing lesions and fleck features using artificial intelligence deep learning construct.The paper concludes with a perspective about using artificial intelligence to potentially find early risk factors or biomarkers that can aid in the prediction of Stargardt disease progression.

Pseudo-Glaucoma after Hypertensive Retinopathy

A 35-year-old Japanese woman showed the typical fundus appearance of acute hypertensive retinopathy, including multiple cotton-wool spots, retinal hemorrhages, star exudates, and disc edema bilaterally. Her systemic blood pressure was high (246/158 mmHg). Nephrologists diagnosed her with secondary hypertension due to immunoglobulin A nephropathy. After 2 years, all signs of acute retinopathy resolved and only multiple striated or sectorial darkening of the fundus (retinal nerve fiber layer defects [NFLD]) remained. Computerized analysis of the macular thickness measurement by optical coherence tomography alerted the risk of glaucoma. NFLD is a hallmark of early glaucoma that is more reliable than IOP elevations since normal tension glaucoma is popular in Japan. To differentiate this case from true glaucoma, information regarding her past history is critical for her future ophthalmologists.

Two-year longitudinal change in choroidal and retinal thickness in school-aged myopic children:exploratory analysis of clinical trials for myopia progression

Background:With increasing axial length(AL)and myopia progression,the micro-structure of the retina and choroid gradually changes.Our study describes the longitudinal changes in retinal and choroidal thickness in school-aged children with myopia and explores the relationship between changes in choroidal thickness and myopia progression.Methods:An exploratory analysis of a randomized trial was performed.Children(n=168,aged 7 to 12 years)with myopia from-0.75 diopter(D)to-4.00 D were enrolled in this prospective longitudinal study.Cycloplegic refraction,AL,retinal and choroidal thicknesses were measured at baseline and at 1-and 2-year follow-ups."Rapid progression myopia"was defined as increasing in myopia>1.00 D and'"stable progression myopia"was≤1.00 D during the 2-year follow-up.Factors affecting the changes in choroidal thickness were analysed using linear mixed models.Results:AL significantly increased by 0.67±0.24 mm with a myopic shift of-1.50±0.64 D over the 2 years.The overall retinal thickness increased from 251.12±15.91μm at baseline to 253.47±15.74μm at the 2-year followup(F=23.785,P<0.001).The subfoveal choroidal thickness decreased from 231.03±54.04μm at baseline to 206.53±59.71μm at the 2-year follow-up(F=73.358,P<0.001).Choroidal thinning was significantly associated with AL elongation(β=-43.579μm/mm,P=0.002)and sex(β=-17.258,P=0.001).Choroidal thickness continued to decrease in subjects with rapid progression(F=92.06,P<0.001)but not in those with steady progression(F=2.23,P=0.119).Conclusion:Significant choroidal thinning was observed and was associated with rapid progression and sex.These findings indicate a need to understand the role of the choroid in eye growth and myopia development.Synopsis/Precis:The macular choroidal thickness of myopic children is relevant to different degrees of myopic progression in this 2-year longitudinal study.These findings suggest that control of choroidal thickness might work to regulate human ocular growth.

A comparative study of alteration in retinal layer segmentation alteration by SD-OCT in neuromyelitis optica spectrum disorders: A systematic review and meta-analysis

Background:To evaluate the feature of different retinal layer segmentation in neuromyelitis optica spectrum disorders(NMOSD)with spectral-domain optical coherence tomography(SD-OCT)and to compare it with that in multiple sclerosis(MS),healthy controls(HC),and idiopathic optic neuritis(ION).Methods:We retrieved four electronic databases,including Pubmed,Embase,Cochrane Library,and Web of Science from inception to September 1st,2021.A meta-analysis was performed to compare different retinal layer segmentation thicknesses between patients with or without a history of optic neuritis(ON)in NMOSD and the control group,including patients with MS,HC,and ION.Results:Forty-two studies were included and the interval between the last ON onset and examination was greater than 3 months.Compared with that in HC eyes,the loss of retinal nerve fiber layer(RNFL)and macular ganglion cell and inner plexiform layer(GC-IPL)was serious in NMOSD eye especially after ON.Moreover,compared with that in ION eyes or MS-related-ON eyes,the injury to the peripapillary retinal nerve fiber layer(pRNFL)was severe in NMOSD-related-ON eyes.In addition,the correlation coefficient between pRNFL and prognostic visual acuity was 0.43.However,the one-arm study revealed the inner nuclear layer(INL)was thickened in NMOSDrelated-ON eyes compared with HC eyes.Conclusions:Inclusion of the RNFL and macular GC-IPL is recommended for monitoring disease progression and attention should be paid to changes in the INL.

Inverted Internal Limiting Membrane Flap Technique for Repair of Large Macular Holes： A Short-term Follow-up of Anatomical and Functional Outcomes

Background：Inverted internal limiting membrane （ILM） flap technique has recently been reported in a limited number of studies as an effective surgical technique for the management of large macular holes （MHs） with fair MH closure rates as well as gains in visual acuity.In the current study,longitudinal changes in multi-focal electroretinogram （mfERG） responses,best-corrected visual acuity （BCVA） and spectral-domain optical coherence tomography （SD-OCT） were evaluated in eyes with large MHs managed by this technique.Methods：A prospective noncontrolled interventional study of eight patients （eight eyes） with large MHs （minimum diameter 〉400 μm） was conducted.All MHs were treated with pars plana vitrectomy and indocyanine green-assisted inverted ILM flap technique.SD-OCT images were used to assess the anatomical outcomes of surgery while BCVA and mfERG were used to evaluate the functional outcomes during a 3-month follow-up.Results：All patients underwent successful intended manipulation and translocation of the ILM flap without flap dislocation and achieved complete anatomical closure.Partial microstructural reconstruction,demonstrated on SD-OCT as restoration of the external limiting membrane and the ellipsoid zone,was observed in all cases as early as 1 month after surgery.Functionally,as compared to baseline,all patients showed improvements in BCVA and all but one in mfERG response during follow-up.However,Pearson＇s test revealed no significant correlations between BCVA and mfERG responses of the fovea and of the macular area at each evaluation time point.Conclusions：Inverted ILM flap technique appeares to be a safe and effective approach for the management of large idiopathic MHs with favorable short-term anatomical and functional results.Postoperative reconstruction of the microstructure generally shows good consistency with improvements in both BCVA and mfERG response,of which the latter might be a supplement for the former in postoperative functional follow-up.

Correlation of In Vivo and In Vitro Methods in Measuring Choroidal Vascularization Volumes Using a Subretinal Injection Induced Choroidal Neovascularization Model

Background： In vivo quantification of choroidal neovascularization （CNV） based on noninvasive optical coherence tomography （OCT） examination and in vitro choroidal flatmount immunohistochemistry stained of CNV currently were used to evaluate the process and severity of age-related macular degeneration （AMD） both in human and animal studies. This study aimed to investigate the correlation between these two methods in murine CNV models induced by subretinal injection. Methods： CNV was developed in 20 C57BL6/j mice by subretinal injection of adeno-associated viral delivery of a short hairpin RNA targeting sFLT-1 （AAV.shRNA.sFLT- 1）, as reported previously. After 4 weeks, CNV was imaged by OCT and fluorescence angiography. The scaling factors for each dimension, x, y, and z （ktm/pixel） were recorded, and the corneal curvature standard was adjusted from human （7.7） to mice （1 .4）. The volume of each OCT image stack was calculated and then normalized by multiplying the number of voxels by the scaling factors for each dimension in Seg3D software （University of Utah Scientific Computing and Imaging Institute, available at http：//www.sci.utah.edu/cibc-software/seg3d.html）. Eighteen mice were prepared for choroidal flatmounts and stained by CD31. The CNV volumes were calculated using scanning laser confocal microscopy after immunohistochemistry staining. Two mice were stained by Hematoxylin and Eosin for observing the CNV morphology. Results： The CNV volume calculated using OCT was, on average, 2.6 times larger than the volume calculated using the laser confocal microscopy. The correlation statistical analysis showed OCT measuring of CNV correlated significantly with the in vitro method （R： = 0.448, P = 0.001, n = 18）. The correlation coefficient for CNV quantification using OCT and confocal microscopy was 0.693 （n = 18, P = 0.001 ）. Conclusions： There is a fair linear correlation on CNV volumes between in vivo and in vitro methods in CNV models induced by subretinal injection. The result might provide a useful evaluation of CNV both for the studies using CNV models induced by subretinal injection and human AMD studies.

Evaluation of markers of outcome in realworld treatment of diabetic macular edema

Objective:To evaluate short-term markers of outcome in diabetic macular edema(DME).Methods:Prospective interventional case series included 122 eyes of 122 patients with recently diagnosed DME.Eyes were treated with a 3-monthly loading dose of ranibizumab or aflibercept and pro re nata thereafter.Serial enhanced deep imaging SD-OCT high resolution scans were used to measure subfoveal choroidal thickness(SFCT)and central retinal thickness(CRT).Anatomic(10%CRT decrease)and functional responses(best corrected visual acuity,BCVA gain≥5 letters)were assessed at 3 months and 6 months using univariate and multivariate analyses.Parameters tested were gender,duration of diabetes,HbA1c,hypertension,CRT,SFCT,BCVA,ellipsoid zone(EZ)status,subfoveal neuroretinal detachment(SND),anti-VEGF used and laser naivety.A logistic regression model was applied to find independent markers outcome.Results:BCVA increased,CRT and SFCT decreased at 3 months and 6 months.Good metabolic control(p=0.003),intact baseline EZ(p=0.030),EZ re-grading at 3 M(p<0.001)and laser naivety(p=0.001)were associated with better functional outcome.The multivariate linear regression model showed that baseline SND and CRT are predictors of anatomic response,while lower baseline BCVA and intact EZ are predictors of functional response.Conclusion:The presence of SND predicts anatomic response only,while an intact EZ is critical to achieve a good functional outcome in DME.