Choroidal Thickness and Its Association With Age,Axial Length,and Refractive Error in Chinese Adults

PurposeTo identify the association between the choroidal thickness (ChT) with age and axial length (AL) under different refractive errors (REs) in Chinese adults.MethodsSwept-source optical coherence tomography was used to measure ChT in 2126 right eyes of 2126 participants. The participants were classified as having pathologic myopia (PM), high myopia without PM (HM), low myopia (LM), and nonmyopia (non-M) according to their REs and META-PM (the Meta-Analysis of Pathologic Myopia) classification criteria.ResultsThe mean age was 52.49 ± 20.39 years (range, 18−93 years), and the mean RE was −5.27 ± 5.37 diopters (D; range, −25.5 to +7.75 D). The mean average ChT was 159.25 ± 80.75 µm and decreased in a linear relationship from non-M to PM (190.04 ± 72.64 µm to 60.99 ± 37.58 µm, P < 0.001). A significant decline in ChT was noted between 50 and 70 years (r = −0.302, P < 0.001) and less rapidly after the age of 70 years (r = −0.105, P = 0.024). No correlation was noted between age and ChT under 50 years (P = 0.260). A significantly higher association with AL was noted in the central fovea (β^HM = −23.92, β^LM = −23.88, β^Non-M = −18.80, all P < 0.001) and parafoveal ChT (β^HM = −22.87, β^LM = −22.31, β^Non-M = −18.61, all P < 0.001) when compared with the perifoveal region (β^HM = −19.80, β^LM = −18.29, β^Non-M = −13.95, all P < 0.001). Within each group of PM, HM, LM, and non-M, regression analysis showed that the coefficients of age and AL with different macular regions of ChT varied significantly.ConclusionsChT was negatively correlated with age after 50 years. The thinning of the choroid was more prominent in the center and parafoveal regions as AL increased. Varied distributions of ChT decrease associated with AL and age were noted among different refractive groups.     

Differences in Retinal and Choroidal Vasculature and Perfusion Related to Axial Length in Pediatric Anisomyopes

PurposeThe purpose of this study was to evaluate the interocular differences in choroidal vasculature, choriocapillaris perfusion, and retinal microvascular network, and to explore their associations with interocular asymmetry in axial lengths (ALs) in children with anisomyopia.MethodsRefractive error, AL, and other biometric parameters were measured in 70 children with anisomyopia. Using optical coherence tomography (OCT) and OCT-angiography, we measured the submacular choroidal thickness (ChT), total choroidal area (TCA), luminal area (LA), stromal area (SA), choroidal vascularity index (CVI), choriocapillaris flow deficit (CcFD), retinal vessel density (VD), and foveal avascular zone (FAZ) area.ResultsThe mean interocular differences in spherical equivalent refraction and AL were −2.26 ± 0.94 diopters and 0.95 ± 0.46 mm, respectively. Submacular ChT, TCA, LA, SA, and CVI were all significantly lower in the more myopic (longer AL) eyes than in the less myopic (shorter AL) fellow eyes. In eyes with longer ALs, both the CcFD and FAZ areas were significantly greater, whereas the superficial and deep retinal VDs were significantly less. After adjusting for corneal power and intraocular pressure, interocular differences in LA (β = −0.774), SA (β = −0.991), and CcFD (β = 0.040) were significantly associated with interocular asymmetry in AL (all P < 0.05).ConclusionsIn pediatric anisomyopes, eyes with longer ALs tended to have lower choroidal vascularity and choriocapillaris perfusion than the contralateral eyes with shorter ALs. Longitudinal investigations would be useful follow-ups to test for a causal role of choroidal circulation in human myopia.     

Evaluation of the White-to-White Distance in 39,986 Chinese Cataractous Eyes

PurposeTo investigate the distribution of white-to-white (WTW) distance and its associations with other biometric parameters in Chinese cataractous eyes.MethodsData on 39,986 eyes from 23,627 Chinese cataract patients were analyzed. Ocular biometric parameters, including WTW distance, corneal curvature, anterior chamber depth (ACD), lens thickness (LT), central corneal thickness (CCT), and axial length (AL), were obtained using the ZEISS IOLMaster 700.ResultsThe mean age of patients was 63.7 ± 12.4 years, and 57.61% were female. The mean WTW distance was 11.69 ± 0.46 mm. The WTW distance was larger in male patients than in female patients for all age groups (all P < 0.001). The WTW distance was positively correlated with corneal curvature and ACD and negatively correlated with age, LT, and CCT (all P < 0.001). Multivariable analysis revealed that a larger WTW distance was associated with younger age; male gender; larger corneal curvature, ACD, and LT; and thinner CCT (all P < 0.001). Notably, the association between WTW distance and AL was not linear. As the AL increased, the WTW distance initially increased, reached a peak in the group with ALs of 24.5 to 26 mm, and then slowly decreased. However, all of the myopic eyes (AL > 24.5 mm) still had larger WTWs than the normal and short eyes (AL ≤ 24.5 mm).ConclusionsIn Chinese cataractous eyes, the WTW distance was larger in younger male patients with flatter corneas, deeper anterior chambers, thicker lenses, and thinner central corneas. The association between WTW distance and AL was not linear, and WTW distance was the largest in eyes with ALs of 24.5 to 26 mm.     

Correlation of vitreous chamber depth with ocular biometry in high axial myopia

Purpose:The proportion of axial length (AL) occupied by vitreous chamber depth (VCD), or VCD:AL, consistently correlates to ocular biometry in the general population. Relation of VCD:AL to ocular biometry in high myopia is not known. The purpose of this study is to evaluate the relation of VCD and VCD:AL to ocular biometry of highly myopic eyes.Methods:This was a cross-sectional retrospective study of records of 214 myopic eyes (<−1 D SE, aged 20–40 years) attending the refractive surgery services. High axial myopia was defined as AL >26.5 mm. Eyes with posterior staphyloma and myopic maculopathy were excluded. Records were assessed for measurements of AL, central corneal thickness (CCT), anterior chamber depth (ACD), lens thickness (LT), white to white diameter (WTW), and vitreous chamber depth (VCD). Groups were formed based on increasing AL, while the sum of CCT, ACD, and LT was recorded as anterior segment depth (AS). The main outcome measure was the correlation of VCD and VCD:AL to ocular biometry. A comparison was also performed based on of degree of axial myopia.Results:Mean age of the patients was 27.0 ± 5.2 years. VCD showed a very strong correlation with AL (R = 0.98, P < 0.001) but did not correlate to any anterior parameter. VCD:AL showed moderate negative relation with AS (R = −0.43, P < 0.001) and ACD (R = −0.3, P < 0.001), while it had a weakly negative relation with LT (R = −0.18, P = 0.006). VCD:AL showed strong negative relation (R > ~0.7) with AS in all individual groups of AL. Among anterior parameters, WTW showed the most consistent relation with ocular biometry.Conclusion:VCD:AL is a better correlate of ocular biometry in high myopia as compared to VCD. However, the correlation is weaker than that noted by previous studies done on the general population. Longitudinal studies of VCD:AL in the younger age group is recommended.     

Comparison of uveal parameters between acute primary angle-closure eyes and fellow eyes in South Indian population

Purpose:To analyze the ocular biometric parameters of eyes with acute primary angle closure (APAC) as compared to fellow eyes.Methods:A cross-sectional study was conducted on 27 patients presenting with recent onset APAC to a tertiary eye institute in India. Anterior and posterior ocular biometric parameters were measured simultaneously by anterior segment optical coherence tomography (AS-OCT), A-scan, ultrasound biomicroscopy (UBM), and B-mode ultrasonogram (USG). The parameters measured were anterior chamber depth (ACD), anterior chamber angle (ACA), angle opening distance (AOD500, AOD750), lens vault (LV), axial length (AL), ciliary body thickness maximum (CBTmax) and at the point of scleral spur (CBT0), anterior placement of the ciliary body (APCB), and retinochoroidal thickness (RCS).Results:Mean age ± SD of patients with APAC was 55.66 ± 7.2 years with female preponderance (21:6 patients). Mean presenting IOP ± SD of the affected eye and fellow eye were 54.74 ± 11.67 mm Hg and 18.7 ± 11.67 mm Hg, respectively. Eyes with APAC had statistically significant narrower anterior ocular biometric parameters, higher LV, decreased ciliary body thickness, more APCB, and longer AL than the fellow eyes. CBTmax is the only variable that had significance (b = −0.421,95% CI: −0.806 to − 0.035, P = 0.034) in the univariate analysis with RCS thickness in APAC eyes. Further, there was a correlation between CBT0 and APCB with CBTmax both in univariate (b = 0.894, P < 0.0001 and b = −0.351, P = 0.039) and multivariable analysis (b = 0.911, P < 0.0001 and b = −0.416, P = 0.016)Conclusion:Compared to the fellow eyes, APAC eyes had different ocular biometric parameters. In addition to known biometric parameters associated with pupillary block (narrower anterior biometric parameters-ACA, ACD, and AOD), our study found multiple nonpupillary block factors such as higher lens vault and thinner and more anteriorly placed ciliary body to be associated with APAC.     

Nomogram of peripapillary retinal nerve fiber layer thickness in myopic eyes of north Indian population

Purpose:To evaluate peripapillary-RNFL thickness in myopia by Cirrus OCT among north Indian population by spherical equivalent (SE), age, gender, and axial length (AL).Methods:This was a cross-sectional study held during 2019–2020. Patients aged 18–60 years underwent ophthalmic examination including retinoscopy, AL, and OCT RNFL thickness. Persons with previous ocular surgery or ocular ailment other than refractive error were excluded. The peripapillary-RNFL thickness was noted and compared by demographic determinants.Results:We examined 300 eyes of 300 persons (mean age: 30.75 ± 8.57 years; 144 males/156 females). Among them, 224 were myopes and 76 were emmetropes (EM). The mean SE was − 3.3 ± 0.4D (range: −11.0D to + 0.37D). The mean AL was 24.61 ± 1.92 mm (22.1–29.5). Overall temporal, nasal, superior, inferior, and mean peripapillary-RNFL thickness was 66.31 ± 7.58, 78.57 ± 16.00, 120.63 ± 11.69, 116.60 ± 15.80, and 95.50 ± 10.84 mm, respectively. Temporal, nasal, superior, inferior, and mean peripapillary-RNFL thickness was 73.97 ± 8.36, 94.84 ± 7.63, 127.96 ± 8.96, 136.89 ± 6.53, and 108.34 ± 6.28 mm, respectively, in EM eyes as compared to 63.71 ± 6.18, 73.05 ± 14.24, 118.21 ± 11.53, 109.71 ± 11.50, and 91.14 ± 8.31 mm, respectively, in myopic eyes (P < 0.001). Association of peripapillary-RNFL thickness with myopia and its different grades was P < 0.001. Association of mean peripapillary-RNFL thickness with age was P > 0.005 and gender was P = 0.168. Correlation between SE and RNFL thickness was positive and significant. Correlation between AL and RNFL thickness was negative but statistically significant. Association of AL with SE was P < 0.001.Conclusion:We provide normative peripapillary-RNFL thickness in the north Indian population in order to help in screening for myopia with comorbidity such as glaucoma based on RNFL thickness.     

Scleral thickness in highly myopic eyes measured by enhanced depth imaging optical coherence tomography

Purpose

The purpose of this study was to determine the subfoveal scleral thickness in highly myopic eyes by enhanced depth imaging spectral-domain optical coherence tomography (EDI-OCT) and to identify the ocular parameters significantly associated with the scleral thickness.

Methods

The subfoveal scleral thickness of myopic eyes (≥−8 diopters (D) or axial length ≥26.5 mm) was examined by EDI-OCT. The correlations between the thickness and the best-corrected visual acuity (BCVA), refractive error, axial length (AL), the subfoveal retinal thickness, choroidal thickness, and posterior staphyloma height 2 mm from the fovea were investigated.

Results

A total of 75 eyes of 54 patients (21 men, 33 women; mean age, 62.3±11.3 years; mean AL, 30.2±1.68 mm) were studied. Eighteen eyes had no pathological retinochoroidal lesions, and 57 eyes had retinochoroidal lesion, that is, myopic schisis, choroidal neovascularization, and other retinochoroidal pathologies. The mean subfoveal scleral thickness was 284.0±70.4 μm, and the thickness was significantly correlated negatively with the absolute value of the nasal and overall average posterior staphyloma height (P<0.05 and P<0.01, respectively). The subfoveal scleral thickness was also significantly correlated negatively with the relative value of the superior, nasal, and overall average posterior staphyloma height (P<0.05, P<0.01, and P<0.001, respectively). Stepwise analyses showed that the factor most significantly associated with the scleral thickness was the average relative posterior staphyloma height (F=16.0, P<0.001). The scleral thickness was not significantly different between eyes with and without myopic retinochoroidal pathologies (P>0.05).

Conclusion

Posterior staphyloma formation was a key factor associated with a posterior scleral thinning in highly myopic eyes.     

Evaluation of the association of macular ganglion cell–inner plexiform layer thickness and myopia in Chinese young adults

PurposeTo describe the distribution of ganglion cell–inner plexiform layer (GCIPL) thickness among Chinese young adults and report whether the decreased GCIPL thickness is associated with myopia.MethodsIn this study, we included Chinese young adults who underwent Cirrus spectral domain-optical coherence tomography (SD-OCT). SD-OCT was used to measure average and minimum GCIPL thickness, and GCIPL thickness at all sectors. Subfoveal choroidal thickness (CT), axial length (AL), and spherical equivalents (SE) were also measured.ResultsA total of 348 eyes were included in the analysis. Average GCIPL thickness showed a significant difference between myopes and emmetropes, with 87.89 ± 3.65 μm for emmetropic groups and 82.65 ± 4.96 μm for myopic groups. The GCIPL thickness was significantly thinner in myopia than in emmetropia at all locations (P < 0.05), affirming that myopia was associated with thinner GCIPL thickness (P = 0.001). The mean subfoveal CT also showed a significant difference between myopes and emmetropes, with 330.57 ± 9.43 μm for emmetropic groups and 265.98 ± 4.12 μm for myopic groups. GCIPL (OR 0.863, 95% CI, 0.785–0.949), AL (OR 2.499, 95% CI, 1.532–4.075) and intraocular pressure (IOP) (OR 1.250, 95% CI, 1.086–1.438) revealed significant associations with myopia. When adjusting for AL, IOP, and anterior chamber depth (ACD) in the myopia subgroup, the GCIPL thickness remained positively associated.ConclusionsIn a specific Chinese young population, myopic eyes have measurably less macular GCIPL thickness than normal eyes. Decreasing GCIPL thickness may be associated with the progression of myopia.Subject terms: Predictive markers, Outcomes research     

Surgical outcome of full-thickness macular hole secondary to tractional retinal detachment in proliferative diabetic retinopathy

Purpose:To evaluate the surgical outcome of full-thickness macular hole (FTMH) secondary to active fibrovascular proliferation (FVP) and tractional retinal detachment (TRD) in eyes with proliferative diabetic retinopathy (PDR), and factors influencing the outcome.Methods:This retrospective study included the patients who underwent vitrectomy for FTMH secondary to PDR TRD from 2016 to 2020. Anatomical and visual outcomes were analyzed after six months along with the factors predicting the final outcome and duration of subretinal fluid (SRF) resolution.Results:Group A (macula-off combined RD, i.e., tractional and rhegmatogenous) included 10 eyes, while group B (macula-threatening TRD) included eight eyes. The mean best-corrected visual acuity improved from logMAR 1.21 (Snellen equivalent: 20/324) to logMAR 0.76 (Snellen equivalent: 20/115) (P = 0.008). Seventeen patients gained ≥1 line(s) of vision. Mean visual gain in groups A and B was 3.7 ± 1.9 and 1.9 ± 1.1 lines, respectively (P = 0.051). MH closed in 88.9% eyes. Type 1 anatomical closure was achieved in 88.9% of eyes. At 6 months, SRF and central macular thickness reduced from 479.6 ± 512.5 μm to 11.4 ± 23.5 μm (P = 0.002) and 874.3 ± 422.6 μm to 207.6 ± 81.7 μm (P = 0.0002), respectively. Finally, macular SRF resolved in all the patients. The mean duration for complete SRF resolution was 4.9 ± 3.2 months. Eyes with a shorter duration of diabetes mellitus (rho = −0.49, P = 0.040) and macula-off combined RD (P = 0.048) took a longer time for complete SRF resolution.Conclusion:Good anatomical and visual outcomes can be achieved in eyes with PDR TRD-associated FTMH. The residual macular SRF resolves slowly after the surgery and extra intervention is not required. Macula-off combined RD is associated with worse outcome and a slower SRF resolution rate.     

Assessment of Choroidal Vascularity and Choriocapillaris Blood Perfusion in Anisomyopic Adults by SS-OCT/OCTA

PurposeTo explore the association of choroidal vascularity and choriocapillaris blood perfusion with myopic severity in anisomyopes.MethodsRefractive error, axial length (AL), and other biometric parameters were measured in 34 anisomyopic young adults. Macular choroidal thickness (ChT) and choroidal vascularity, including total choroidal area (TCA), luminal area (LA), stromal area (SA), and choroidal vascularity index (CVI), were determined from swept-source optical coherence tomography (SS-OCT) vertical and horizontal B-scans. The percentage of choriocapillaris flow voids (FV%) was obtained from en face SS-OCT-angiography.ResultsThe spherical equivalent refraction (SER) was –3.35 ± 1.25 diopters in the more myopic eyes and –1.25 ± 1.17 diopters in the less myopic eyes (P < 0.001). The interocular difference in SER was highly correlated with that in AL (P < 0.001). The macular ChT, TCA, LA, and SA were smaller in the more myopic eyes than in the less myopic eyes in both vertical and horizontal scans (all P < 0.001). Importantly, the CVIs in vertical and horizontal scans were smaller and the FV% was greater in the more myopic eyes (P < 0.05). In vertical scans, the interocular difference in CVIs was correlated with that in the SER, AL, and ChT (all P < 0.05). The interocular difference in FV% was correlated with that in SER, AL, and vertical and horizontal ChTs (all P < 0.05).ConclusionsChoroidal vascularity and choriocapillaris blood perfusion were lower in the more myopic eyes of anisomyopic adults. These changes were correlated with the severity of myopia and choroidal thinning, indicating that choroidal blood flow is disturbed in human myopia.     

Astigmatism and biometric optic components of diode laser-treated threshold retinopathy of prematurity at 9 years of age

Purpose

To assess the prevalence of astigmatism and its relationship with biometric optic components in preterm school children with diode laser-treated threshold retinopathy of prematurity (ROP).

Methods

A prospective, cross-sectional study in which cycloplegic keratometry, refraction, and ultrasound biometric measurement of optic components were performed on 24 consecutive preterm children with diode laser-treated threshold ROP at the age of 9 years. The study results were compared with data on 1021 age-matched full-term control children from a national survey.

Results

The laser-treated eyes had a mean astigmatism of 3.47 D, with a mean spherical equivalent of −4.49 D. Of the 46 eyes studied, 98% of eyes showed astigmatism ≥0.5 D and 50% had high astigmatism (>3.0 D). Most astigmatic eyes (97.7%) showed with-the-rule astigmatism, with the mean plus cylinder axis at 89.30^o. Further correlation analysis showed the astigmatism in refraction was highly correlated with the corneal astigmatism (r=0.921, P<0.001) and the vertical corneal curvature (r=0.405, P=0.005). There was significantly steeper vertical corneal curvature (P=0.003) and flatter horizontal corneal curvature (P=0.031) in eyes with laser-treated ROP when compared with age-matched full-term controls. The eyes with laser-treated ROP also show significantly thicker lens (3.93 mm) and shallower anterior chamber depth (ACD; 2.92 mm) than full-term controls (P<0.001).

Conclusions

There is significantly higher prevalence and greater magnitude of astigmatism in eyes with laser-treated threshold ROP compared with full-term controls. The steeper vertical corneal curvature component contributes to the increased astigmatism in eyes with laser-treated ROP.     

Biometric and refractive changes after orbital decompression in Korean patients with thyroid-associated orbitopathy

Purpose

To determine the biometric and refractive changes after orbital decompression in Korean patients with thyroid-associated orbitopathy (TAO).

Methods

Retrospective, observational study (between October 2012 and September 2014) was performed. Patients with TAO undergoing orbital decompression for stable proptosis received ophthalmic examinations, including Hertel exophthalmometry, A-scan biometry, autorefraction measures, corneal topography, and wavefront aberration measures, before orbital decompression and again 2 months after surgery.

Results

Included in the study were 43 eyes from 23 patients. The mean exophthalmometric value decreased by 4.1 mm 2 months after orbital decompression (P<0.001). On average, axial length (AL) increased significantly by 0.08 mm (P<0.001); specifically, 37 (86%) of the 43 eyes had increased AL. Whereas anterior chamber depth and lens thickness showed no significant changes (P=0.086 and P=0.905, respectively), the mean spherical refraction and spherical equivalent (SE) decreased by 0.35 and 0.48 D, respectively (P=0.008 and P<0.001, respectively). However, cylindrical refraction and axis showed no significant changes (P=0.057 and P=0.218, respectively). The changes in AL and SE were significantly correlated (R=−0.411, P=0.009). Notably, there were no changes in corneal topography or wavefront aberration after orbital decompression.

Conclusions

TAO patients who underwent orbital decompression showed myopic refractive change via increase in AL. Possible refractive changes should be considered in cases of TAO complaining of decreased visual acuity after orbital decompression.     

Recovery From Form-Deprivation Myopia in Chicks Is Dependent Upon the Fullness and Correlated Color Temperature of the Light Spectrum

PurposeThe purpose of this study was to evaluate the impact of full-spectrum light-emitting diodes mimicking sunlight (Sunlike LEDs) on ocular growth and refractive error development in a chicken model of myopia.MethodsOne-day old chicks (n = 39) were distributed into 3 groups and raised for 28 days in isoluminant (approximately 285 lux) fluorescent (n = 18, [FL-4000], correlated color temperature [CCT] = 4000 K) or Sunlike LED (n = 12, [SL-4000], CCT = 4000 K; n = 9, [SL-6500], CCT = 6500 K) white lighting environments. Form-deprivation myopia was induced monocularly from day 1 post-hatching (D1) until D14. On D14, form deprivation was halted and the recovery of form-deprived (FD) eyes was monitored until D28. Axial length (AL), refraction, choroidal thickness, and anterior chamber depth were measured in vivo on D1, D7, D14, D22, and D28. Differences in outcome measures between eyes and groups were compared using 2-way repeated-measures ANOVA.ResultsAL and myopic refraction of FD eyes increased similarly among groups during form-deprivation. FD eyes of animals raised under SL-4000 (D22: P < 0.001 and D28: P < 0.001) and SL-6500 (D22: P = 0.006 and D28: P < 0.001) recovered faster from axial elongation compared with animals raised under FL-4000. The refractive status of FD eyes reared under SL-6500, not under FL-4000 or SL-4000, was similar to control eyes on D28 (P > 0.05). However, SL-4000 and SL-6500 exhibited similar refraction on D28 than FL-4000 (P > 0.05). Choroidal thickness was significantly greater in FD eyes of chickens raised under SL-6500 than in animals raised under FL-4000 (P = 0.03).ConclusionsCompared to fluorescent light, moderate intensities of full-spectrum Sunlike LEDs can accelerate recovery from form-deprivation myopia in chickens, potentially through a change in the choroid-mediated pathway.     

A Study of the Association Between Retinal Vessel Geometry and Optical Coherence Tomography Angiography Metrics in Diabetic Retinopathy

PurposeThe purpose of this study was to investigate whether optical coherence tomography angiography (OCTA) metrics are related to retinal vessel geometry parameters in diabetic retinopathy (DR).MethodsIn total, 119 eyes (119 patients) were included in this retrospective cross-sectional study. Retinal vessel geometry parameters were analyzed using semi-automated software. OCTA metrics were analyzed using automated manufacturer-provided algorithms. Associations between the severity of DR and retinal vessel geometry parameters and OCTA metrics were evaluated. Multivariable regression analyses were performed to evaluate associations between retinal vessel geometry parameters and OCTA metrics after adjusting for clinical characteristics and DR severity.ResultsDR severity was negatively associated with the following: arteriole–venular ratio (P = 0.039), arteriolar network fractal dimension (FDa; P = 0.003), arteriolar junctional exponent deviation (P = 0.037), venular junctional exponent deviation (P = 0.036), vessel area density (VAD) of the superficial capillary plexus (SCP) and deep capillary plexus (DCP; P < 0.001, both), vessel length density (VLD) of the SCP and DCP (P < 0.001, both), and foveal avascular zone (FAZ) circularity (P < 0.001). DR severity was positively associated with the central retinal venular equivalent caliber (P = 0.005), arteriolar branching coefficient (BCa; P = 0.010), venular branching coefficient (P = 0.007), and FAZ size (P = 0.002). In multivariable regression analyses, the following retinal vessel geometry parameters and OCTA metrics were associated: FDa with VAD of the SCP (β = 0.40, P < 0.001), FDa with VLD of the SCP (β = 0.01, P < 0.001), and BCa with FAZ circularity (β = −1.02, P = 0.001).ConclusionsIn DR, changes in retinal arteriolar geometry parameters were significantly associated with OCTA metrics, which reflect DR pathophysiology.     

The anterior and posterior biometric characteristics in primary angle-closure disease: Data based on anterior segment optical coherence tomography and swept-source optical coherence tomography

Purpose:Obtaining a better understanding of the pathogenesis of primary angle-closure disease (PACD) still requires studies that provide measurements of anterior and posterior biometric characteristics together and that assess the relationship between them.Methods:In total, 201 eyes were enrolled in this cross-sectional study: 50 normal controls, 49 primary angle-closure suspect (PACS), 38 primary angle closure (PAC), and 64 primary angle-closure glaucoma (PACG) eyes. The anterior and posterior structural features were measured by anterior segment optical coherence tomography and swept-source optical coherence tomography.Results:All PACD groups had smaller anterior chamber depth (ACD), anterior chamber area (ACA), anterior chamber volume (ACV), angle opening distance at 750 μm from the scleral spur (AOD750), trabecular–iris space area at 750 μm from the scleral spur (TISA750), and angle recess area (ARA), as well as a larger lens vault (LV), than controls (all P < 0.001). The PACS and PAC groups had thicker iris thickness at 750 μm from the scleral spur (IT750) than controls (P = 0.017 and P = 0.002, respectively). Choroidal thickness (CT) was not statistically different among normal, PACS, PAC, and PACG eyes. Univariate and multivariate linear regression analysis revealed a significant association between thinner IT750 and increased CT in PACD eyes (P = 0.031, univariate analysis; P = 0.008, multivariate analysis).Conclusion:Thinner iris thickness was associated with increased CT in PACD eyes; however, the underlying mechanism needs further investigation.     

Rapid Myopic Progression in Childhood Is Associated With Teenage High Myopia

PurposeThe purpose of this study was to evaluate the association of childhood progression of spherical equivalent (SE) with high myopia (HM) in teenagers in the Singapore Cohort of Risk factors for Myopia (SCORM).MethodsWe included 928 SCORM children followed over a mean follow-up of 6.9 ± 1.0 years from baseline (6–11 years old) until their teenage years (12–19 years old). Cycloplegic autorefraction and axial length (AL) measurements were performed yearly. The outcomes in teenagers were HM (SE ≤ −5 diopter [D)], AL ≥ 25 mm, SE and AL. Three-year SE and AL progression in childhood and baseline SE and AL with outcomes were evaluated using multivariable logistic or linear regression models, with predictive performance of risk factors assessed using the area under the curve (AUC).ResultsAt the last visit, 9.8% of teenagers developed HM and 22.7% developed AL ≥ 25 mm. In multivariate regression analyses, every −0.3 D/year increase in 3-year SE progression and every 0.2 mm/year increase in 3-year AL progression were associated with a −1.14 D greater teenage SE and 0.52 mm greater teenage AL (P values < 0.001). The AUC (95% confidence interval [CI]) of a combination of 3-year SE progression and baseline SE for teenage HM was 0.97 (95% CI = 0.95 – 0.98). The AUC of 3-year AL progression and baseline AL for teenage AL ≥ 25 mm was 0.91 (95% CI = 0.89 – 0.94).ConclusionsThree-year myopia progression in childhood combined with baseline SE or AL were good predictors of teenage HM. Clinicians may use this combination of factors to guide timing of interventions, potentially reducing the risk of HM later in life.     

Volumetric Optical Imaging and Quantitative Analysis of Age-Related Changes in Anterior Human Vitreous

PurposeThe purpose of this study was to characterize age-related changes in anterior human vitreous with 3-D swept source optical coherence tomography (SS-OCT) and evaluate associations with axial length (AL) and contrast sensitivity function (CSF).MethodsThere were 49 phakic eyes in 49 patients (40.0 ± 19.3 years) had 3-D volumetric scanning of the lens and retrolental vitreous with SS-OCT at 1050 nm. OCT-derived indices of vitreous optical density (VOD), vitreous opacification ratio (VOR), and lens optical density (LOD) were correlated with AL and double-pass assessment of retinal point spread function (Objective Scatter Index [OSI]). CSF was measured using an adaptive-optics visual simulator (area under log-log contrast sensitivity function [AULCSF]).ResultsVitreous SS-OCT detected gel vitreous, liquefied lacunae, Berger''s space, retrolental laminae, and fibrous opacifications. VOD, VOR, and LOD showed high reproducibility (intraclass correlation coefficients 0.968, 0.975, and 0.998, respectively). VOD was highly correlated with VOR (Pearson''s R = 0.96, P < 0.000001). VOD, VOR, and LOD correlated with age (R = 0.48, 0.58, and 0.85, P < 0.001 for each). VOR and LOD correlated with OSI (R = 0.36, P = 0.0094, and R = 0.36, P = 0.0096, respectively). VOR correlated negatively with AULCSF (R = −0.53, P < 0.00009), which was related to OSI. Myopic eyes had higher OSI than nonmyopic eyes (P = 0.0121), consistent with correlation between OSI and AL (R = 0.37, P = 0.0091). Multivariable regression confirmed these findings.ConclusionsSS-OCT visualized microstructural features of anterior human vitreous, where opacification is associated with increased light scattering and CSF degradation. SS-OCT enables high-resolution optical evaluation of vitreous opacities.     

Effect of systemic blood pressure on optical coherence tomography angiography in glaucoma patients

BackgroundThe association between retinal microvascular structure and glaucoma has been revealed in multiple studies using optical tomography angiography (OCTA), but limited information on the macular vessel density (mVD) in patients with glaucoma is available. In this study, we tried to identity the factors that affected macular VD (mVD) in glaucomatous eyes.MethodsThis retrospective cross-sectional study evaluated OCT and OCTA images from 92 eyes from 58 healthy subjects and 179 eyes from 103 glaucoma patients using the SD-OCT database from July 2017 to July 2018. Glaucomatous eyes were further divided into two groups according to history of disc haemorrhage (DH). Association between mVD and demographic characteristics, ganglion cell-inner plexiform layer (GCIPL) thickness, visual field mean deviation (MD) and systemic blood pressure was analysed in each group.ResultsIn both healthy and glaucomatous eyes, mVD was inversely associated with age (β = −0.035, P = 0.025; β = −0.039, P = 0.018). In the glaucomatous eyes, mVD was significantly decreased, as the MD value was worse (β = 0.109, P = 0.002). In glaucomatous eyes with DH, mVD decreased as blood pressure increased (β = -0.111, P = 0.003)ConclusionsReduced mVD is more common in older individuals in both healthy and glaucomatous eyes, and correlates with functional deterioration than structural damage in glaucomatous eyes. In glaucomatous eyes with DH, high systemic BP is associated with a reduction in mVD. This may indicate that glaucoma patients with DH are more susceptible to vascular damage secondary to hypertensionSubject terms: Optic nerve diseases, Ocular hypertension     

Changes in choroidal thickness after prophylactic iridectomy in primary angle closure suspect eyes using enhanced depth imaging optical coherence tomography

Purpose:

The aim of the present study was to evaluate the effect of surgical peripheral iridectomy (SPI) on choroidal thickness in primary angle-closure suspect (PACS) eyes.

Materials and Methods:

This was a prospective observational case series of 30 subjects with PACS. Ocular biometry was performed before SPI (baseline) and then 1 week later. Choroid was imaged by enhanced depth imaging optical coherence tomography (EDI-OCT). The choroidal thickness of the subfoveal area at 1 and 3 mm diameter around the fovea was determined. Central anterior chamber depth (ACD), lens thickness (LT), vitreous chamber depth (VCD), and axial length (AL) were measured by A-scan ultrasound. Parameters were compared before SPI (baseline) and 1 week later.

Results:

Thirty eyes of 30 patients with mean age of 61.53 ± 7.98 years were studied. There was no significant difference in the choroidal thickness at all macular locations before and after SPI (all P > 0.05). Mean subfoveal choroidal thickness was 279.61 μm ± 65.50 μm before and 274.54 μm ± 63.36 μm after SPI (P = 0.308). There was also no significant change in central ACD, LT, VCD, and LT after SPI (all P > 0.05).

Conclusions:

SPI does not appear to alter choroidal thickness in PACS eyes, as assessed using EDI-OCT. Long-term follow-up of PACS eyes treated with SPI may provide further insight into the effects of this treatment modality on the choroid.     

Longitudinal Macular Retinal and Choroidal Microvasculature Changes in High Myopia

PurposeThe purpose of this study was to determine the longitudinal changes in macular retinal and choroidal microvasculature in normal healthy and highly myopic eyes.MethodsSeventy-one eyes, including 32 eyes with high myopia and 39 healthy control eyes, followed for at least 12 months and examined using optical coherence tomography angiography imaging in at least 3 visits, were included in this study. Fovea-centered 6 × 6 mm scans were performed to measure capillary density (CD) of the superficial capillary plexus (SCP), deep capillary plexus (DCP), and choriocapillaris (CC). The rates of CD changes in both groups were estimated using a linear mixed model.ResultsOver a mean 14-month follow-up period, highly myopic eyes exhibited a faster rate of whole image CD (wiCD) loss (−1.44%/year vs. −0.11%/year, P = 0.001) and CD loss in the outer ring of the DCP (−1.67%/year vs. –0.14%/year, P < 0.001) than healthy eyes. In multivariate regression analysis, baseline axial length (AL) was negatively correlated with the rate of wiCD loss (estimate = −0.27, 95% confidence interval [CI] = −0.48 to −0.06, P = 0.012) and CD loss in the outer ring (estimate = −0.33, 95% CI = −0.56 to −0.11, P = 0.005), of the DCP. The CD reduction rates in the SCP and CC were comparable in both groups (all P values > 0.05).ConclusionsThe rate of CD loss in the DCP is significantly faster in highly myopic eyes than in healthy eyes and is related to baseline AL. The CD in the outer ring reduces faster in eyes with longer baseline AL.