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.

Three-dimensional choroidal vascularity index and choroidal thickness in fellow eyes of acute and chronic primary angle-closure using swept-source optical coherence tomography

AIM:To compare the three-dimensional choroidal vascularity index(CVI)and choroidal thickness between fellow eyes of acute primary angle-closure(F-APAC)and chronic primary angle-closure glaucoma(F-CPACG)and the eyes of normal controls.METHODS:This study included 37 patients with unilateral APAC,37 with asymmetric CPACG without prior treatment,and 36 healthy participants.Using swept-source optical coherence tomography(SS-OCT),the macular and peripapillary choroidal thickness and three-dimensional CVI were measured and compared globally and sectorally.Pearson’s correlation analysis and multivariate regression models were used to evaluate choroidal thickness or CVI with related factors.RESULTS:The mean subfoveal CVIs were 0.35±0.10,0.33±0.09,and 0.29±0.04,and the mean subfoveal choroidal thickness were 315.62±52.92,306.22±59.29,and 262.69±45.55μm in the F-APAC,F-CPACG,and normal groups,respectively.All macular sectors showed significantly higher CVIs and choroidal thickness in the F-APAC and F-CPACG eyes than in the normal eyes(P<0.05),while there were no significant differences between the F-APAC and F-CPACG eyes.In the peripapillary region,the mean overall CVIs were 0.21±0.08,0.20±0.08,and 0.19±0.05,and the mean overall choroidal thickness were 180.45±54.18,174.82±50.67,and 176.18±37.94μm in the F-APAC,F-CPACG,and normal groups,respectively.There were no significant differences between any of the two groups in all peripapillary sectors.Younger age,shorter axial length,and the F-APAC or F-CPACG diagnosis were significantly associated with higher subfoveal CVI and thicker subfoveal choroidal thickness(P<0.05).CONCLUSION:The fellow eyes of unilateral APAC or asymmetric CPACG have higher macular CVI and choroidal thickness than those of the normal controls.Neither CVI nor choroidal thickness can distinguish between eyes predisposed to APAC or CPACG.A thicker choroid with a higher vascular volume may play a role in the pathogenesis of primary angle-closure glaucoma.

Non-linear relationship between age and subfoveal choroidal thickness in Chinese patients with proliferative diabetic retinopathy

BACKGROUND No study has investigated the change regularity between age and subfoveal choroidal thickness(SFCT)in proliferative diabetic retinopathy(PDR).AIM To investigate the relationship between the SFCT and age in Chinese patients with PDR.METHODS This was a cross-sectional retrospective study.The participants were hospitalized individuals with type 2 diabetes who underwent vitrectomy for PDR.Contralateral eyes that met the criteria were included in the study.All necessary laboratory tests were performed at the time of admission.Central macular thickness(CMT)and SFCT were two quantitative assessments made using enhanced depth imaging optical coherence tomography.CMT was measured automatically and SFCT was measured manually with digital calipers provided by the Heidelberg Eye Explorer software.RESULTS The final analysis included a total of 234 individuals with PDR.The average age was 55.60 years old±10.03 years old,and 57.69%of the population was male.Univariate analysis revealed a significant negative connection between age and SFCT in patients with PDR[β=-2.44,95%confidence interval(95%CI):-3.46 to-1.42;P<0.0001].In the fully adjusted model,the correlation between SFCT and age remained steady(β=-1.68,95%CI:-2.97 to-0.39;P=0.0117).Spline smoothing showed that the relationship between SFCT and age in patients with PDR was non-linear,with an inflection point at 54 years of age.CONCLUSION Our findings suggest that age is a key determinant of choroidal thickness.The non-linear link between SFCT and age in PDR patients should be taken into account.

Evaluation of retinal and choroidal thickness changes in overweight and obese adults without ocular symptoms by swept-source optical coherence tomography

AIM:To evaluate the relationship of overweight and obesity with retinal and choroidal thickness in adults without ocular symptoms by swept-source optical coherence tomography(SS-OCT).METHODS:According to the body mass index(BMI)results,the adults enrolled in the cross-sectional study were divided into the normal group(18.50≤BMI<25.00 kg/m^(2)),the overweight group(25.00≤BMI<30.00 kg/m^(2)),and the obesity group(BMI≥30.00 kg/m^(2)).The one-way ANOVA and the Chi-square test were used for comparisons.Pearson’s correlation analysis was used to evaluate the relationships between the measured variables.RESULTS:This research covered the left eyes of 3 groups of 434 age-and sex-matched subjects each:normal,overweight,and obesity.The mean BMI was 22.20±1.67,26.82±1.38,and 32.21±2.35 kg/m^(2) in normal,overweight and obesity groups,respectively.The choroid was significantly thinner in both the overweight and obesity groups compared to the normal group(P<0.05 for all),while the retinal thickness of the three groups did not differ significantly.Pearson’s correlation analysis showed that BMI was significantly negatively correlated with choroidal thickness,but no significant correlation was observed between BMI and retinal thickness.CONCLUSION:Choroidal thickness is decreased in people with overweight or obesity.Research on changes in choroidal thickness contributes to the understanding of the mechanisms of certain ocular disorders in overweight and obese adults.

Automatic fovea detection and choroid segmentation for choroidal thickness assessment in optical coherence tomography

AIM:To develop an automated model for subfoveal choroidal thickness(SFCT)detection in optical coherence tomography(OCT)images,addressing manual fovea location and choroidal contour challenges.METHODS:Two procedures were proposed:defining the fovea and segmenting the choroid.Fovea localization from B-scan OCT image sequence with three-dimensional reconstruction(LocBscan-3D)predicted fovea location using central foveal depression features,and fovea localization from two-dimensional en-face OCT(LocEN-2D)used a mask region-based convolutional neural network(Mask R-CNN)model for optic disc detection,and determined the fovea location based on optic disc relative position.Choroid segmentation also employed Mask R-CNN.RESULTS:For 53 eyes in 28 healthy subjects,LocBscan-3D’s mean difference between manual and predicted fovea locations was 170.0μm,LocEN-2D yielded 675.9μm.LocEN-2D performed better in non-high myopia group(P=0.02).SFCT measurements from Mask R-CNN aligned with manual values.CONCLUSION:Our models accurately predict SFCT in OCT images.LocBscan-3D excels in precise fovea localization even with high myopia.LocEN-2D shows high detection rates but lower accuracy especially in the high myopia group.Combining both models offers a robust SFCT assessment approach,promising efficiency and accuracy for large-scale studies and clinical use.

Choroidal thickness,myopia,and myopia control interventions in children:a Meta-analysis and systemic review

AIM:To investigate changes of choroidal thickness(ChT) in children with myopia and the effect of current myopia control interventions on ChT.METHODS:Major literature databases were searched for studies relevant to myopia in children.All studies used swept-source optical coherence tomography(SS-OCT) or enhanced depth imaging optical coherence tomography(EDI-OCT) to measure the ChT value.The weighted mean difference(WMD) and 95% confidence interval(CI) were pooled to evaluate ChT in myopia children.RESULTS:A total of 11 eligible articles,including 1693 myopic and 1132 non-myopic eyes,were included in the first Meta-analysis.The sub-foveal choroidal thickness(SFCT;WMD=-40.06,95%CI,-59.36 to-20.75,P<0.001) and ChT at other sectors were significantly thinner in myopic eyes compared with the non-myopic eyes.The Meta-analysis revealed that the ChT decreased horizontally from the temporal sector toward the nasal sector in the pediatric myopia population.Another 11 studies reporting the effect of myopia control interventions were included in the second Meta-analysis for the relationship between myopia control treatments and ChT.SFCT significantly increased after orthokeratology(OK) treatment and OK combined with 0.01% atropine(OKA) treatment(WMD=19.47,95%CI,15.96 to 22.98,P<0.001;WMD=21.81,95%CI,12.92 to 29.70,P<0.001,respectively).The forest plots showed that SFCT changed little in myopic children receiving 0.01% atropine(P=0.30).Furthermore,the Meta-analysis showed that OK treatment had a stronger effect on the value of SFCT in myopic children as compared with 0.01% atropine(WMD=9.86;95%CI,-0.21 to 19.93,P=0.05).There is no difference between the treatment with OK and OKA treatment in ChT in myopic children(P=0.37).CONCLUSION:The ChT in myopic eyes is thinner than that in non-myopic eyes in pediatric population.Myopia control interventions including OK and OKA lead to ChT thickening,but other treatments such as 0.01% atropine did not show an increase in ChT.

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.

Choroidal thickness measurements in young Saudi adult population: a cross-sectional study

AIM:To determine the choroidal thickness(CT)in young healthy Saudi adults using spectral-domain optical coherence tomography(SD-OCT)with an automated CT segmentation software.METHODS:Fifty-eight young adults(total of 116 eyes),39 males and 19 females participated in this study between the ages of 18 and 38y(mean 22.65±3.9y).All participants underwent ophthalmic screening examination,including the SD-OCT for measurements of CT in each quadrant egmented into five eccentric regions starting from the foveal region up to 4.5 mm towards the periphery.RESULTS:The choroid was thickest in the foveal region(central 1 mm,300±60μm)and began to progressively thinner beyond the parafovea(1.5–2.5 mm,284±67μm)towards the peripheral region(3.5–4.5 mm from the fovea,254±83μm).The superior choroid showed the thickest profile(309±57μm),while the nasal choroid exhibited the thinnest(229±76μm).The rate of the thinning with increasing eccentricity was more predominant in the nasal choroid,which thinned from the foveal region(294±58μm)to the peripheral region(158±55μm).The superior and inferior choroid did not show a statistically significant thinning with eccentricity(all P>0.05).There was no statistically significant difference in the CT between gender,age,and laterality of the eyes(all P>0.05).A significant association of myopia with thinner subfoveal choroid was observed(Pearson’s,r=0.37),and regression analysis showed that a 10.3μm choroidal thinning for each diopter increase of myopia.CONCLUSION:CT profile depends on eccentric and the quadrant.The CT profile across the measured area in the young Saudi adult population is comparable to other previous reports.Refractive error is critical for CT evaluation.

Change in subfoveal choroidal thickness after argon laser panretinal photocoagulation

AIMTo evaluate changes in subfoveal choroidal thickness (SFCT) and macular thickness as measured by enhanced depth imaging spectral-domain optical coherence tomography (EDI-OCT) after argon laser panretinal photocoagulation (PRP) in patients with severe diabetic retinopathy.

Choroidal thickness measurements with optical coherence tomography in branch retinal vein occlusion

AIM： To evaluate central macular thickness（CMT） and mean choroidal thickness（MCT） in eyes with branch retinal vein occlusion（BRVO）, before and after ranibizumab treatment using spectral domain-optical coherence tomography（SD-OCT）.·METHODS： Forty-two patients with unilateral BRVO and macular edema were included in this study. There were 25 men and 17 women. Using SD-OCT, choroidal thickness was measured at 500 μm intervals up to 1500μm temporal and nasal to the fovea. MCT was calculated based on the average of the 7 locations. All the eyes with BRVO were treated with intravitreal ranibizumab（0.5 mg/0.05 m L）. Comparisons between the BRVO and fellow eyes were analyzed using Mann-Whitney U test. Preinjection and post-injection measurements were analyzed using Wilcoxon test and repeated measure analysis.· RESULTS： At baseline, there was a significant difference between the BRVO and fellow eyes in MCT[BRVO eyes 245（165-330） μm, fellow eyes 229（157-327） μm]and CMT [BRVO eyes 463（266-899） μm, fellow eyes 235（148-378） μm（P =0.041, 0.0001, respectively）]. Following treatment, CMT [295（141-558） μm] and MCT [229（157-329） μm] decreased significantly compared to the baseline measurements（P =0.001, 0.006, respectively）.Also BCVA（log MAR） improved significantly（P=0.0001） in the BRVO eyes following treatment. After treatment CMT[BRVO eyes 295（141-558） μm, fellow eyes 234（157-351） μm]and MCT [BRVO eyes 229（157-329） μm, fellow eyes 233（162-286） μm] values did not reveal any significant difference in BRVO eyes and fellow eyes（P=0.051, 0.824,respectively）.· CONCLUSION： In eyes with BRVO, CMT and MCT values are greater than the fellow eyes, and decrease significantly following ranibizumab injection.

Association of choroidal thickness with early stages of diabetic retinopathy in type 2 diabetes

AIM：To assess the correlation between choroidal thickness（CT） and the early stages of diabetic retinopathy（DR） in type 2 diabetic patients.METHODS：We divided 83 diabetic patients（51-80 years of age;50 females） into non diabetic retinopathy group（NDR） and mild/moderate nonproliferative diabetic retinopathy（NPDR） group,and compared them with 26 non-diabetic control subjects（51-78 years of age;16 females）.Subfoveal choroidal thickness（SFCT） and parafoveal choroidal thickness（PFCT） were measured using enhanced depth imaging spectral-domain optical coherence tomography（EDI-OCT）.Ocular health status,disease duration,body mass index,and hemoglobin A1c（Hb A1c） were recorded.RESULTS：The mean ages of the NDR,NPDR,and control groups were 68.0±6.9y,67.8±6.4y,and 65.1±6.3y,respectively（P=0.17）.Pearson correlation of the right and left eyes for the control subjects was 0.95 and for the NDR subjects was 0.93.SFCT for the right eyes of the controls was 252.77± 41.10 μm,which was significantly thicker than that of the right eyes in NDR group（221.51±46.56 μm） and the worse eyes of the NPDR group（207.18±61.87 μm;ANOVA,P〈0.01）.In the diabetic patients pooled together,age was the only variable significantly associated with SFCT（multiple linear regression analysis,P=0.01）.CONCLUSION：CT decreased significantly in the NDR and mild/moderate NPDR eyes compared with the control eyes.Age is significantly associated with SFCT in the diabetic patients.Diabetic choroidopathy may be present before clinical retinopathy.

Comparison of choroidal thickness in high myopic eyes after FS-LASIK versus implantable collamer lens implantation with swept-source optical coherence tomography

AIM:To investigate the changes in choroidal thickness(CT)in high myopic eyes after femtosecond laser-assisted in situ keratomileusis(FS-LASIK)surgery or central hole implantable collamer lens(ICL V4c)implantation using swept-source optical coherence tomography(SS-OCT).METHODS:We examined the right eyes of 116 patients with high myopia who were candidates for FS-LASIK surgery and ICL implantation.Sixty eyes underwent ICL V4c implantation and 56 eyes were subjected to FS-LASIK surgery.The CT was measured with SS-OCT.All data were recorded preoperatively and 2 h,1 wk,1 and 3 mo postoperatively.Other demographic information was collected,including age,sex,uncorrected visual acuity(UCVA),best corrected visual acuity(BCVA),spherical equivalent(SE),intraocular pressure(IOP)and axial length(AL).RESULTS:The UCVA improved in both groups and showed no significant differences between groups.There also were no significant differences between the two groups in postoperative BCVA and SE(P=0.581 and 0.203,respectively).The foveal CTs,inner nasal and outer nasal CTs were significantly thicker at 2 h postoperatively in both groups(P<0.05)but returned to baseline levels in 1 wk;after 1 mo,no significant differences were found relative to the preoperative values.At 3 mo in each group,nine regions showed variations in the CT as compared with preoperative thickening,but only the foveal and nasal area CTs preoperative differences were statistically significant(P<0.05).In addition,there was no significant difference in 9 regions of CT between the two groups at all follow-up times(P>0.05).CONCLUSION:The CTs after ICL implantation and FSLASIK surgery are significantly thicker than those before operation,especially in the foveal and nasal areas,but there is no significant difference between the two methods.

Correlation between choroidal thickness and intraocular pressure after 23-gauge vitrectomy for idiopathic epiretinal membrane

AIM： To determine the relationship between the subfoveal choroidal thickness（CT） and intraocular pressure（IOP） following idiopathic epiretinal membrane（ERM） surgery.METHODS： Retrospective observational case series of patients who had undergone 23-gauge vitrectomy for an ERM. The measurements of CT and IOP were done at the baseline and 1 d, 1 wk, 1, 3, 6, and 12 mo after the surgery.RESULTS： Forty-four eyes of 43 patients with a mean age of 69.8±9.5 y were studied. The CT was 200.8±86.3 μm at the baseline, 210.1±83.5 μm at 1 d, 213.2±85.4 μm at 1 wk, 203.1±84.0 μm at 1 mo, 197.5±85.5 μm at 3 mo, 197.7±84.0 μm at 6 mo, and 191.2±86.8 μm at 12 mo after surgery. The CT on day 1 and week 1 after the surgery was significantly thicker than that at the baseline CT（P=0.0023 and P〈0.0001）. The CT at 12 mo after surgery was significantly thinner than the baseline（P=0.0062）. The IOP on day 1 and week 1 were significantly lower than the baseline（P〈0.0001 and P=0.0042）. The IOP at 1, 3, 6, and 12 mo after surgery were significantly higher than the baseline IOP（P=0.0087, P=0.0023, P〈0.00051, and P〈0.0001）. The rates of changes in the CT between baseline and day 1 and week 1 were significantly and negatively correlated with the rates of change in the IOP（P〈0.0001 and P=0.046）. In the group with the IOP change rate of-30% or less at 1 d postoperatively, the change rate of CT was-21.1% to 31.2%（9.8%±12.4%） and in the group of-29% or more, it was-8.9% to 28.0%（2.6%±8.9%）. The change rate of CT in the group with the IOP change rate of-30% or less was significantly higher than the group of-29% or more（P=0.016）.CONCLUSION： CT increases soon after the ERM surgery which is probably due to the transient hypotony, showing that IOP may be a significant confounding factor for CT.

Changes in choroidal thickness in healthy pediatric individuals: a longitudinal study

AIM： To investigate the changes in the choroidal thickness in healthy pediatric children in a longitudinal study, and to determine the ocular and systemic parameters that were significantly correlated with the changes in the choroidal thickness. METHODS： This study included 64 eyes of 34 healthy Japanese children with a mean age（±SD） of 4.4（±0.4）y（range, 3.6-5.8 y） at baseline. Swept-source optical coherence tomography（SS-OCT） was used to record images of the retina and choroid at the baseline and after a mean followup period of about 1.5 y. The 3 D raster scan protocol was used to construct the choroidal thickness map. Mean choroidal thickness was calculated for each of the nine sectors of the Early Treatment Diabetic Retinopathy Study grid. Best-corrected visual acuity, axial length, body height, and weight were also measured. Changes in measurements were defined as the baseline values subtracted from the values at the final visit. A generalized estimating equation was used to eliminate the effect of within-subject intereye correlations. RESULTS： The mean central choroidal thickness was significantly reduced during the follow-up period（baseline, 301.8±8.6 μm; final visit, 286.6±8.0 μm, P〈0.001）. The decrease in the choroidal thickness was greatest in the central sector, followed by the sectors of the inner and outer rings. The inner and outer rings had diameters of 1 to 3 mm and 3 to 6 mm, respectively. The changes in the choroidal thickness in the central, inner ring, and outer ring sectors were significantly and negatively correlated with the age, baseline body height, baseline body weight, and elongation of the axial length. CONCLUSION： These results indicate that the choroidal thickness among preschool-aged Japanese children decreased significantly during the follow-up period. The choroidal thinning is significantly associated with the elongation of axial length. These characteristics should be considered in the evaluation of choroidal thickness in younger children with retinochoroidal disorders.

Evaluation of choroidal thickness using spectral-domain optical coherence tomography in patients with severe obstructive sleep apnea syndrome: a comparative study

AIM: To assess choroidal thickness in patients with severe obstructive sleep apnea syndrome(OSAS) and compare them with healthy controls, using spectral domain optical coherence tomography(OCT).METHODS: In this observational, cross-sectional study,choroidal thicknesses of 23 newly severe OSAS patients and 23 body mass index- age- and sex-matched healthy subjects were measured using a high-speed, high-resolution frequency domain- OCT device( λ = 840 nm,26 000 A-scans/s, 5 μm axial resolution). All patients underwent a complete ophthalmic examination before the measurements. OCT measurements were taken at the same time of day(9:00 a.m.), in order to minimize the effects of diurnal variation.RESULTS: There was a statistically significant difference in median choroidal thickness between the OSAS patients(201 μm; range 145-237 μm) and the controls(324 μm; range 296-383 μm;P 【0.001). There were significant differences at all measurement points(P 【0.001 for all). The apnea-hypopnea index(AHI)values were more than 30 in all OSAS patients and the mean AHI was 48.57 ±6.54. The interexaminer intraclass correlation coefficient(ICC) for the mean choroidal thickness was 0.938(95% CI, 0.908-0.985) and ICC was greater than 0.90 for all measurement points.CONCLUSION: The decreased choroidal thickness of patients with severe OSAS might be related to the the autonomic disregulation associated with this disease.Further studies are needed to evaluate the etiopathologic relationship between choroidal thickness and OSAS.

Association between choroidal thickness and anterior chamber segment in eyes with narrow or open-angle

AIM: To investigate the relationship between choroidal thickness and anterior chamber segment in subjects with eyes with narrow or open-angle. METHODS: The subfoveal choroidal thickness was measured with enhanced depth -imaging optical coherence tomography and anterior chamber parameters were measured with ultrasound biomicroscopy in one eye of 23 subjects with open-angle eyes and 38 subjects with narrow-angle eyes. The mean age was 59.52 +/- 7.04y for narrow-angle subjects and 60.76 +/- 7.23y for open angle subjects (P=0.514). Multivariate linear regression analysis was performed to assess the association between choroidal thickness and narrow -angle parameters. RESULTS: There were no differences in subfoveal choroidal thickness between open - and narrow-angle subjects (P=0.231). Anterior chamber parameters, including central anterior chamber depth, trabecular iris angle, iris thickness 500 mu m from the scleral spur (IT500), and ciliary body thickness at 1 mm and 2 mm from the sclera! spur (CBT1, CBT2) showed significant differences between the two groups (P<0.05). Subfoveal choroidal thickness showed negative correlation (beta=-0.496, P=0.016) only with anterior chamber depth in the open angle group and with age (beta=-0.442, P=0.003) and 11500 (beta=-0.399, P=0.008) in the narrow-angle group. However, subfoveal choroidal thickness was not correlated with trabecular iris angle, anterior chamber depth, ciliary body thickness, or central corneal thickness in the narrow-angle group. CONCLUSION: Choroidal thickness does not differ in the two groups and has not correlated with anterior chamber parameters in narrow-angle subjects, suggesting a lack of relationship between choroidal thickness and primary angle-closure glaucoma.

Optical coherence tomography with or without enhanced depth imaging for peripapillary retinal nerve fiber layer and choroidal thickness

AIM：To assess peripapillary retinal nerve fiber layer（RNFL）and choroidal thickness obtained with enhanced depth imaging（EDI）mode compared with those obtained without EDI mode using Heidelberg Spectralis optical coherence tomography（OCT）.METHODS：Fifty eyes of 25 normal healthy subjects and32 eyes of 20 patients with different eye diseases were included in the study.All subjects underwent 3.4 mm diameter peripapillary circular OCT scan centered on the optic disc using both the conventional and the EDI OCT protocols.The visualization of RNFL and choroidoscleral junction was assessed using an ordinal scoring scale.The paired t-test,intraclass correlation coefficient（ICC）,95%limits of agreement（LoA）,and Bland and Altman plots were used to test the agreement of measurements.RESULTS：The visibility score of RNFL obtained with and without EDI was of no significant difference（P=0.532）,the visualization of choroidoscleral junction was better using EDI protocol than conventional protocol（P〈0.001）.Peripapillary RNFL thickness obtained with EDI was slightly thicker than that obtained without EDI（103.25±9.42μm vs 101.87±8.78μm,P=0.010）.The ICC of the two protocols was excellent with the value of 0.867 to 0.924,the 95%LoA of global RNFL thickness was between-10.0 to 7.4μm.Peripapillary choroidal thickness obtained with EDI was slightly thinner than that obtained without EDI（147.23±51.04μm vs 150.90±51.84μm,P〈0.001）.The ICC was also excellent with the value of 0.960 to 0.987,the 95%LoA of global choroidal thickness was between-12.5 to 19.8μm.CONCLUSION：Peripapillary circular OCT scan with or without EDI mode shows comparable results in the measurement of peripapillary RNFL and choroidal thickness.

Comparison of peripapillary and macular choroidal thickness and ganglion cell complex thickness in glaucomatous and healthy eyes

AIM: To assess choroidal thickness(CT) and its association with ganglion cell-inner plexiform layer thickness(GCIPLT) and retinal nerve fiber layer thickness(RNFLT) in open angle glaucoma(OAG) comparing with preperimetric glaucoma(PPG) and normal eyes.METHODS: Totally 55 eyes of OAG, 40 eyes of PPG, and 40 eyes of age-matched normal eyes were studied. Peripapillary CT(PCT), macular CT(MCT), RNFLT, and GCIPLT were evaluated. Relationship between the CT with RNFLT and GCIPLT were studied. The correlation between CT and confounding variables as gender, age, intraocular pressure, and visual field mean deviation were analyzed. RESULTS: Mean PCT were 113.6±39.1 μm in OAG, 116.3±42.7 μm in PPG, and 148.9±41.7 μm in normal eyes. PCT and MCT was thinner in OAG compared to healthy eyes. There was a significant correlation for PCT and mean RNFLT in 1, 2, 6, and 7 clock hours of OAG eyes. The difference in PCT remained after adjusting for axial length, age, and disc area(P=0.003). No significant correlation was shown between MCT and mean GCIPLT in all eyes.CONCLUSION: PCT is thinner in OAG and PPG compared with healthy eyes. The correlation of RNFLT and PCT found in OAG and PPG is not revealed in normal eyes.

The diurnal variation pattern of choroidal thickness in macular region of young healthy female individuals using spectral domain optical coherence tomography

AIM： To investigate the pattern of diurnal variations of choroidal thickness of macular region of healthy individuals. ~ METHODS： A prospective study of 32 healthy female subjects was conducted. Each subject underwent 1） a questionnaire on daily schedule, 2） the Pittsburgh Sleep Quality Index questionnaire （PSQI）, and 3） ocular examinations including an eye dominance test, fundus photography, and sequential optical coherence tomography （OCT） imaging, on two separate days at five fixed 3h time intervals. Choroidal thickness was measured by two masked graders. RESULTS： A significant diurnal variation of choriodal thickness at fovea （P〈0.001）, at 500 μm nasal （P〈0.001）, temporal to fovea （P=0.01） or 1500 μm nasal to fovea （P= 0.001） was observed. The median choroidal thickness peaked at 11：00 at fovea （P=0.01）, at 500μm nasal （P = 0.009） and temporal （P=0.03） to fovea. The median amplitude of foveal choroidal thickness was 20.5 pm （13, 31） and 20.0 μm （12.5, 28.2） for the first and second series of measurements, respectively. The greater amplitude of foveal choroidal thickness was associated with thickner initial foveal choroidal thickness [ 0.05 （0.03, 0.08）, P= 0.01], dominant eye 10.51 （4.02, 14.60）, P=0.04] in the multivariate linear regression. CONCLUSION： Our data show a significant diurnal variation of the choroidal thickness at fovea, at 500 μm nasal and temporal to fovea and 1500 μm nasal to fovea. Thicker initial foveal choroidal thickness and being dominant eye may influence the amplitude of foveal choroidal thickness.

Choroidal thickness in pregnant women : a cross-sectional study

AIM: To investigate choroidal thickness in pregnant women and compare the measurements with those of normal nonpregnant women. METHODS: Using enhanced depth imaging optical coherence tomography (EDI-OCT), choroidal thickness was measured at the fovea and at 1 mm and 3 mm superior, inferior, temporal, and nasal to the fovea in both healthy pregnant women and nonpregnant women. Pearson correlation analysis was performed to evaluate the relationships between subfoveal choroidal thickness (SFCT) and the demographic and ocular parameters. Pooled odds ratio (OR) and 95% confidence interval (CI) were calculated using fixed-effects model when Meta analyses were conducted. RESULTS: Comparison of choroidal thickness between the groups showed that it was significantly greater in healthy pregnant women's eyes than in normal nonpregnant women's eyes at all locations except at 3 mm superior and 3 mm temporal from the fovea (P<0.05). The mean SFCT was 344.13 +/- 50.94 mu m in healthy pregnant women's eyes and 315.03 +/- 60.57 mu m in normal nonpregnant women's eyes, with a statistically significant difference (P=0.008). Pearson correlation analysis showed that age and axial length were significantly related to SFCT in healthy pregnant women, normal nonpregnant women, and all subjects. The results of our cross-sectional study were consistent with the results of the further Meta analysis, with a pooled weighted mean difference (WMD) of 33.66 mu m (95% CI: 26.16 to 41.15) for SFCT. CONCLUSION: Our results, along with the comprehensive Meta-analysis, suggest that choroidal thickness in healthy pregnant women is greater than that in normal nonpregnant women.