Influence of Refractive Condition on Retinal Vasculature Complexity in Younger Subjects

Objective. The aim of this study was to compare the retinal vasculature complexity between emmetropia, and myopia in younger subjects.Methods. A total of 82 patients (24.12±1. 25years) with two types of refractive conditions, myopia and emmetropia were enrolled in this study. Refraction data were converted to spherical equivalent refraction. These retinal images (right eyes) were obtained from NAVIS Lite Image Filing System and the vasculature complexity was measured by fractal dimension (Df), quantified using a computer software following a standardized protocol.Results. There was a significant difference (P < 0.05) in the value ofDfbetween emmetropic (1.5666 ± 0.0160) and myopic (1.5588 ± 0.0142) groups. A positive correlation (rho = 0.260,P < 0.05) between theDfand the spherical equivalent refraction was detected in this study. Using a linear model, it was estimated that 6.7% of the variation inDfcould be explained by spherical equivalent refraction.Conclusions. This study provides valuable findings about the effect of moderate to high myopia on the fractal dimension of the retinal vasculature network. These results show that myopic refraction in younger subjects was associated with a decrease inDf, suggesting a loss of retinal vessel density with moderate to high myopia.

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An objective study of negative accommodation

Russian Ophthalmological Journal ◽

10.21516/2072-0076-2019-12-1-64-68 ◽

2019 ◽

Vol 12 (1) ◽

pp. 64-68

Author(s):

E. P. Tarutta ◽

N. A. Tarasova ◽

G. A. Markosyan ◽

N. Yu. Kushnarevich ◽

T. Yu. Larina

Keyword(s):

Open Field ◽

High Myopia ◽

Spherical Equivalent ◽

First Case ◽

Significant Difference ◽

Minimal Difference ◽

Negative Tone ◽

Objective Study ◽

Fellow Eyes

Purpose: to study the dynamic refraction of myopic eyes at the time when the object is fixed in an open field at a distance of 5 m and determine habitual accommodation tone (HAT) in an open field. Material and methods. 130 patients (260 eyes) aged 6 to 23 years (ave. 11.26 ± 0.2 years) with an average refraction spherical equivalent of -4.16 ± 0.13 D were divided into 4 groups, depending on the degree of myopia. The HAT was measured by an automatic binocular open field (OP) autorefkeratometer Grand Seiko WR-5100K (Japan), while the HAT according to Yuri Rosenblum was determined by a conventional autorefractometer Nidek. Results. Comparing noncycloplegic and cycloplegic refraction using the two devices, we obtained different results. In the first case, we found the maximal difference of -0.15 D (-4.38 – (-4.23)), and in the second case, the minimal difference of -0.09 D (-4.16 – (-4.07)). Over the whole group, HAT according to Yuri Rosenblum averaged -0.21 ± 0.02 D. In patients with low myopia HAT was the highest and averaged -0.33 ± 0.03 D. In patients with moderate myopia an average HAT level was -0.23 ± 0.03, and in high myopia it was -0.19 ± 0.04 D. Patients with anisomyopia showed a significant difference of the tone between the fellow eyes: the eyes with lower refraction showed a HAT of -0.21 ± 0.03 D, while for the worse eye it was 0.06 ± 0,11 D (p < 0.05) (i.e. a negative accommodation tone). Over the whole contingent HAT OP averaged -0.17 ± 0.02 D: in patients with low myopia it averaged -0.22 ± 0.04 D, in those with moderate myopia, -0.27 ± 0.02 D, in high myopia — -0.09 ± 0.04 D. PTA OP patients with anisomyopia averaged -0.07 ± 0.03 D and demonstrated a significant difference between the eyes (-0.26 ± 0.03 D for the better eyes and 0.12±0.06 D — for the worse eyes, p < 0.01). A negative tone of accommodation of HAT OP in myopia occurs, on average, in 30% of patients; the frequency was maximal in high myopia (50 %) and minimal in moderate myopia (13.8 %). Conclusions. Objectively determined the weakening of the far dynamic refraction as compared with the static refraction (in terms of cycloplegia) was objectively determined. Thus, the existence of negative accommodation was confirmed.

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Subfoveal Scleral Thickness is Associated With Peripheral Retinal Changes in High Myopia in Children and Adolescents

10.21203/rs.3.rs-167986/v1 ◽

2021 ◽

Author(s):

Wenli Zhang ◽

Tingkun Shi ◽

Shirong Chen ◽

Haoyu Chen

Keyword(s):

Risk Factors ◽

High Risk ◽

Children And Adolescents ◽

Axial Length ◽

High Myopia ◽

Thickness Measurement ◽

Low Risk ◽

Spherical Equivalent ◽

Cross Sectional ◽

Spherical Equivalent Refraction

Abstract Background This study aims to identify the risk factors in peripheral retinal changes (PRC) associated with high myopes among children and adolescents.Methods This is a cross-sectional study on children and adolescents diagnosed with high myopia. The subjects involved underwent a series of ocular examinations, including the dilated fundus examination for PRC and the swept-source optical coherence tomography for foveal retinal, choroidal and scleral thickness measurement. Then, the variables were compared among the eyes with high risk, low risk, and no PRC. Spearman correlation was applied to evaluate the relationship between the parameters and the extent of PRC. Logistic regression was performed to identify the potential risk factors.Results A total of 117 eyes from 117 subjects were recruited. The prevalence of PRC was 57.3% (67 eyes), while that of high-risk PRC was 22.2% (26 eyes). A number of significant differences were observed in the mean subfoveal scleral thickness, spherical equivalent refraction, and axial length among the eyes with high-risk, low-risk, and no PRC (p < 0.01, p < 0.01, p = 0.048, respectively). Compared with spherical equivalent (r = 0.32, p < 0.01) and axial length (r = 0.18, p = 0.05), subfoveal scleral thickness exhibited higher correlation coefficient with PRC (r=-0.38, p < 0.01). Subfoveal scleral thickness and spherical equivalent refraction were identified as the independent risk factors for both PRC and high-risk PRC.Conclusion It was demonstrated that there was a correlation between subfoveal scleral thickness and PRC. The eyes with thinner subfoveal scleral thickness carried a higher risk of PRC.

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Pupil barycenter configuration in patients with myopia and hyperopia

10.21203/rs.3.rs-255996/v1 ◽

2021 ◽

Author(s):

Hacı Koç ◽

Faruk Kaya

Keyword(s):

Prospective Study ◽

Pupil Diameter ◽

Anterior Chamber Depth ◽

Spherical Equivalent ◽

Distance Measurements ◽

Low Coherence ◽

Significant Difference ◽

Spherical Equivalent Refraction ◽

Thickness Measurements ◽

Optical Low Coherence Reflectometry

Abstract Purpose To compare the pupil barycenter configurations that can be used to calculate the kappa angle in terms of distance in patients with myopia and hyperopia. Method : This prospective study evaluated 394 eyes of 197 patients. The patients were divided into two groups according to their spherical equivalent values: the myopic group (mean spherical equivalent refraction < − 0.50 D) and the hyperopia group (mean spherical equivalent refraction > + 0.50 D). The two groups were further subdivided according to severity (myopic group: mild, <−0.50 and ≤ − 3.00 D; moderate, <−3.00 and ≤ − 6.00 D; severe, <−6.00 D; hyperopic group: mild, ≥+0.50 and ≤ + 2.00 D; moderate, >+2.00 and ≤ + 4.00 D; severe, >+4.00 D). The pupil and iris barycenter distance measurements and other parameters were obtained through optical low-coherence reflectometry. Results Of the 197 patients, 109 (55.3%) were female and 88 (44.7%) were male, and their age ranged from 7 to 60 years (mean, 35.16 ± 14.75 years). The average pupil barycenter measurements originating from the kappa angle distances were 0.38 ± 0.15 and 0.21 ± 0.11 mm in patients with hyperopia and myopia, respectively. Corneal and lens thickness measurements were higher in patients with hyperopia, whereas anterior chamber depth and pupil diameter measurements were higher in patients with myopia. No significant difference in astigmatism or white-to-white measurements was observed between patients with hyperopia and those with myopia. Conclusion The kappa angle distances are higher in hyperopia than in myopia. The pupil barycenter measurement from the kappa angle distance can be an alternative for the evaluation of the kappa angle.

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Optical and visual quality comparison of implantable collamer lens and femtosecond laser assisted laser in situ keratomileusis for high myopia correction

International Journal of Ophthalmology ◽

10.18240/ijo.2021.05.15 ◽

2021 ◽

Vol 14 (5) ◽

pp. 737-743

Author(s):

Zheng Jiang ◽

◽

Dong-Qiang Luo ◽

Jiao Chen ◽

◽

...

Keyword(s):

Visual Acuity ◽

Femtosecond Laser ◽

Clinical Outcomes ◽

High Myopia ◽

Cutoff Frequency ◽

Laser In Situ Keratomileusis ◽

Spherical Equivalent ◽

Implantable Collamer Lens ◽

Significant Difference

AIM: To compare clinical outcomes and refractive stability of implantable collamer lens (ICL) implantation and femtosecond laser assisted laser in situ keratomileusis (FS-LASIK) for high myopia correction. METHODS: The Optical Quality Analysis System (OQAS) was used to evaluate clinical outcomes objectively after operation for high myopia correction. We compared the two procedures in terms of 1-year changes in uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), safety index, efficacy index, spherical equivalent, modulation transfer function (MTF) cutoff frequency, strehl ratio (SR) and objective scatter index (OSI). RESULTS: At 1y postoperatively, the safety indices were 1.33±0.27 in ICL group, and 1.17±0.24 in FS-LASIK group. 39.58% in the ICL group and 27.59% in the FS-LASIK group gained CDVA in 2 lines or better than that in preoperative CDVA. The efficacy indices were 1.28±0.22 in ICL group, and 1.13±0.26 in FS-LASIK group. The changes of spherical equivalent from 1wk to 1y postoperatively was -0.12±0.37 D in ICL group, and -0.79±0.58 D in FS-LASIK group (P<0.05). Spherical equivalent within ±0.50 D was achieved in 97.92% in ICL group and 68.97% in FS-LASIK group. MTF cutoff frequency were higher with ICL as compared to FS-LASIK (P<0.05) at each postoperative follow-up stage; for postoperative 1mo later, SR was statistically significant difference between two groups (P<0.05); with no statistically significant difference in OSI between two groups (P>0.05) in postoperative 3mo later. CONCLUSION: ICL implantation and FS-LASIK procedures both provide good safety and predictability in high myopia correction. ICL implantation provides better clinical outcomes and refractive stability than FS-LASIK.

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The Comparison of Regional RNFL and Fundus Vasculature by OCTA in Chinese Myopia Population

Journal of Ophthalmology ◽

10.1155/2018/3490962 ◽

2018 ◽

Vol 2018 ◽

pp. 1-10 ◽

Cited By ~ 8

Author(s):

Yuanjun Li ◽

Hamza Miara ◽

Pingbo Ouyang ◽

Bing Jiang

Keyword(s):

Significant Positive Correlation ◽

Optical Coherence Tomography Angiography ◽

Retinal Vessel ◽

Retinal Nerve Fibre Layer ◽

Vessel Density ◽

Spherical Equivalent ◽

Positive Correlation ◽

Rnfl Thickness ◽

Nerve Fibre Layer ◽

Retinal Vessel Density

Purpose. To determine the correlations between peripapillary vessel density, retinal nerve fibre layer (RNFL) thickness, and myopic indices at retina quadrants with optical coherence tomography angiography (OCTA) in Chinese. Methods. Fifty-six subjects with a mean spherical equivalent (MSE) of −3.63 ± 0.29 D were included. Peripapillary RNFL thickness and retinal vessel density in four sectors (superior, nasal, inferior, and temporal quadrants) were determined by OCTA, and correlations of the main outcomes were analyzed. Results. Negative correlations were found between the peripapillary RNFL thickness and axial length (AL) at superior (r=−0.335, P=0.001) and inferior (r=−0.551, P<0.001) quadrants. There was a significant positive correlation with spherical equivalent (SE) at the corresponding quadrants as well as at the nasal quadrant (r=0.339, P=0.001; r=0.379, P<0.001; and r=0.209, P=0.039, resp.). Peripapillary retinal vessel density was also negatively correlated with AL at the nasal quadrant (r=−0.392, P<0.001), and only at the nasal quadrant, there was a positive correlation between the peripapillary vessel density and SE (r=0.319, P=0.001). Conclusions. The degree of myopia and elongation of AL were negatively correlated with peripapillary RNFL thickness at superior and inferior quadrants and with peripapillary retinal vessel density at the nasal quadrant.

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Clinical Observation of Retinal Vessel Density In Type 2 Diabetic Patients With High Mopyopia

10.21203/rs.3.rs-1162983/v1 ◽

2021 ◽

Author(s):

Ruifeng Su ◽

Zhiyang Jia

Keyword(s):

High Myopia ◽

Retinal Vessel ◽

Vessel Density ◽

Diabetic Patients ◽

Type 2 Diabetic Patients ◽

Group A ◽

Group B ◽

Retinal Vessel Density ◽

Type 2 Diabetic

Abstract Purpose: To quantitatively analyze the difference of superficial and deep retinal vessel density between diabetic patients with high myopia , diabetic patients without high myopia and normal subjects.Methods: This cross-sectional study recruited type 2 diabetic patients with no history of ocular treatment in Shijiazhuang, China.Thirty type 2 diabetic patients with high myopia (30 eyes) were included in group A, 30 type 2 diabetic patients (30 eyes) without myopia were included in group B. Another 30 sex-,age-matched healthy volunteers (30 eyes)were included in group C. The superficial and deep retinal vessel density were measured and compared among the three groups to determine the effects of high myopia on diabetes.Results: No statistically significant differences in central superficial retinal vessel density(CSVD) was found in three groups（P＞0. 05).There were significant differences in the temporal superficial retinal vessel density（TSVD）,superior superficial retinal vessel density(SSVD), nasal superficial retinal vessel density(NSVD),inferior superficial retinal vessel density(ISVD) between the three groups, respectively (P＜0.05).TSVD,SSVD,NSVD,ISVD in group A were all lower than those in group B and group C(P ＜0.05).ISVD in group B was lower than that in group C and no statistically significant differences in TSVD,SSVD,NSVD were found between groups B and C(P＞0.05). There were significant differences in central deep retinal vessel density(CDVD),temporal deep retinal vessel density(TDVD),superior deep retinal vessel density(SDVD), nasal deep retinal vessel density(NDVD),inferior deep retinal vessel density(IDVD) between the three groups, respectively (P＜0.05).CDVD in group A was higher than that in group B , but there was no significant difference between group A and group C.TDVD,SDVD,NDVD,IDVD in group A were all lower than those in group B and C(P ＜0.05),and those in group B were lower than those in group C(P ＜0.05).Conclusion: Myopia and diabetes are important factors affecting vessel density. The parafoveal superficial and deep vessel density of type 2 diabetic patients with high myopia were lower than those of diabetics and normal persons. However,there was no difference in macular fovea superficial and deep retinal vessel density between diabetic patients with high myopia and normal persons.Myopia did not show a protective effect on retinal vessel density reduction in diabetic patients.

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Vessel Density and Structural Measurements in Primary Angle-Closure Suspect Glaucoma Using Optical Coherence Tomography Angiography

BioMed Research International ◽

10.1155/2020/7526185 ◽

2020 ◽

Vol 2020 ◽

pp. 1-6

Author(s):

Yi Zha ◽

Juanjuan Chen ◽

Shuyu Liu ◽

Jinfei Zhuang ◽

Jianqiu Cai

Keyword(s):

Retinal Vessel ◽

Normal Subjects ◽

Vessel Density ◽

Angle Closure ◽

Control Group ◽

Fiber Layer ◽

Primary Angle Closure ◽

Rnfl Thickness ◽

Significant Difference ◽

Retinal Vessel Density

Purpose. To measure the macular retinal vessel density (VD) and peripapillary retinal nerve fiber layer (RNFL) in primary angle-closure suspects (PACS) by Angio-OCT to be compared with normal subjects. Methods. Primary angle-closure suspect patients and normal subjects were enrolled in this study. The demographic and clinical characteristics of all subjects, such as RNFL thickness, retinal vessel density, and ocular perfusion pressure, were compared. Results. No significant difference was found in both groups on age, sex distribution, intraocular pressure (IOP), and retinal vessel density. The PACS group exhibited significantly thicker RNFL thickness compared with the control group. The deep vessel density was negatively associated with age ( P = − 0.034 ), while IOP had negative association with ACD ( P = − 0.019 ). OPP was independently associated with RNFL ( B = 0.334 , P = 0.038 ) in the PACS group. Conclusions. OCTA showed significant thicker change on RNFL in the PACS group. Only OPP was independently associated with RNFL in the PACS group.

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The retinal vasculature pathophysiological changes in vision recovery after treatment for indirect traumatic optic neuropathy patients

Graefe s Archive for Clinical and Experimental Ophthalmology ◽

10.1007/s00417-021-05208-x ◽

2021 ◽

Author(s):

Yang Gao ◽

Jinmiao Li ◽

Huan Ma ◽

Cong Nie ◽

Xi Lv ◽

...

Keyword(s):

Oxygen Saturation ◽

Optic Neuropathy ◽

Retinal Vessel ◽

Vessel Density ◽

Retinal Vasculature ◽

Traumatic Optic Neuropathy ◽

Retinal Blood Vessels ◽

Retinal Artery ◽

Retinal Vessel Density ◽

Arteries And Veins

Abstract Purpose To evaluate the retinal vasculature pathophysiological changes of indirect traumatic optic neuropathy (ITON) patients after effective surgery. Methods Monocular ITON patients who underwent endoscopic trans-ethmosphenoid optic canal decompression (ETOCD) or conservative treatments in Zhongshan Ophthalmic Center from January 2017 to June 2020 were recruited. Visual acuity (VA), visual evoked potential (VEP), oxygen saturation of retinal blood vessels (SO2), and optical coherence tomography angiography (OCT-A) were measured. All patients were followed up at least 3 months after treatments. Results A total of 95 ITON patients were recruited, including 77 patients who underwent ETOCD and 18 patients who underwent conservative treatments. After treatments, more patients received ETOCD (59/77 = 76.6%) presented with improved VA compared with the patients with conservative treatments (6/18 = 33.3%). Compared with the pre-therapeutic measurements, VEP were significantly improved after surgery in ETOCD-treated patients (P < 0.05). Latent periods of P1 and N2, as well as amplitude of P2 of VEP parameters, showed more sensitive to vision recovery (P < 0.05). Retinal artery SO2 and the differences between arteries and veins were improved in ETOCD-treated patients (P < 0.05). Meanwhile, with OCT-A examination, the retinal thickness and retinal vessel density were notably better in ETOCD-treated patients after surgery than that in patients received conservative treatments (P < 0.05). Conclusions Vision recovery after effective treatment of ITON patients was associated with the increased oxygen saturation of retinal vessels, better availability of oxygen in the retina, greater vessel density, and thicker retinas, which might further underlie the vasculature mechanism of vision recovery in ITON patients.

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