Optical Coherence Tomography to Assess Neurodegeneration in Phenylalanine Hydroxylase Deficiency

In phenylalanine hydroxylase (PAH) deficiency, an easily feasible method to access the progression of neurodegeneration is warranted to contribute to current discussions on treatment indications and targets. The objective of the present study was to investigate whether optical coherence tomography (OCT) measures as markers of neurodegeneration differ between patients with PAH deficiency and healthy controls (HCs) according to phenotype and metabolic control. In this single-center cross-sectional study, 92 patients with different phenotypes of PAH deficiency [PAH deficiency not requiring treatment, early treated phenylketonuria (ETPKU), and late-diagnosed phenylketonuria (PKU)] compared with 76 HCs were examined using spectral-domain OCT. Indices of phenylalanine elevation and variability were correlated with OCT parameters. Late-diagnosed PKU patients showed reduced peripapillary retinal nerve fiber layer (pRNFL) thickness and combined ganglion cell and inner plexiform layer (GCIPL) volume. Adult ETPKU patients were found to have lower GCIPL volume (p = 0.016), which correlated with the indices of phenylalanine control. In pediatric ETPKU patients with poor metabolic control, pRNFL was significantly reduced (p = 0.004). Patients with PAH deficiency not requiring treatment did not exhibit retinal degeneration. Inner nuclear layer (INL) was significantly increased in the pediatric ETPKU patients, driven by those with current poor metabolic control (p = 0.006). Our data provide evidence of retinal neuroaxonal degeneration and INL swelling, depending on the phenotype, current age, and metabolic control. These findings suggest that OCT is suitable to investigate neurodegeneration in PKU and we propose OCT as a sensitive, reliable, safe, low-burden, and low-cost examination for future multicenter studies.

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Determinants of vessel defects in superficial and deep vascular layers in normal-tension glaucoma using optical coherence tomography angiography

Scientific Reports ◽

10.1038/s41598-021-89428-5 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Jiyun Lee ◽

Chan Kee Park ◽

Hae-Young Lopilly Park

Keyword(s):

Optical Coherence Tomography ◽

Optical Coherence Tomography Angiography ◽

Deep Layer ◽

Plexiform Layer ◽

Normal Tension Glaucoma ◽

Mean Deviation ◽

Inner Plexiform Layer ◽

Optical Coherence ◽

Fiber Layer ◽

Cross Sectional

AbstractWe investigated the characteristics of localized vessel density defects (VD) either in the deep or superficial vascular layer of normal-tension glaucoma patients using optical coherence tomography angiography (OCTA). In this retrospective, cross-sectional study, 74 eyes with localized retinal nerve fiber layer (RNFL) defect were included. The relationships between the widths of the VD in the superficial and deep layer and ocular factors were evaluated. Eyes with greater deep VD were significantly older (P = 0.023). The IOP measured at OCTA exam was significantly related to the width of the deep VD (P = 0.009). By contrast, average ganglion cell inner plexiform layer thickness (GCIPLT) was substantially related to the width of the superficial VD (P = 0.004). In logistic regression analysis, aging was noticeably associated with wider deep VD, whereas worse mean deviation (MD) had a significant association with wider superficial VD (P = 0.001, P = 0.003, respectively). In sum, while changes of the superficial layer seemed an overall ramification of glaucomatous damages, the deep layer was more likely to be affected by factors related to ocular microcirculation, such as IOPs and older age. Thus, looking into the deep vascular layer using OCTA could identify risk factors related to the disturbance in ocular microcirculation.

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Determinants of Vessel Defects in Superficial and Deep Vascular Layers in Normal-Tension Glaucoma Using Optical Coherence Tomography Angiography

10.21203/rs.3.rs-138088/v1 ◽

2021 ◽

Author(s):

Jiyun Lee ◽

Chan Kee Park ◽

Hae-Young Park

Keyword(s):

Optical Coherence Tomography ◽

Optical Coherence Tomography Angiography ◽

Deep Layer ◽

Plexiform Layer ◽

Normal Tension Glaucoma ◽

Superficial Layer ◽

Inner Plexiform Layer ◽

Optical Coherence ◽

Fiber Layer ◽

Cross Sectional

Abstract We investigated the characteristics of localized vessel density defects (VD) either in the deep or superficial vascular layer of normal-tension glaucoma patients using optical coherence tomography angiography (OCTA). In this retrospective, cross-sectional study, 74 eyes with localized retinal nerve fiber layer (RNFL) defect were included. The relationships between the widths of the VD in the superficial and deep layer and ocular factors were evaluated. Eyes with greater deep VD were significantly older (P = 0.023). Baseline and treated IOPs were significantly related to the width of the deep VD (P=0.009 and 0.014, respectively). By contrast, average ganglion cell inner plexiform layer thickness (GCIPLT) was substantially related to the width of the superficial VD (Both Ps=0.004). In logistic regression analysis, aging was noticeably associated with wider deep VD, whereas worse pattern standard deviation (PSD) had a significant association with wider superficial VD (Both Ps=0.001). In sum, while changes of the superficial layer seemed an overall ramification of glaucomatous damages, the deep layer was more likely to be affected by factors related to ocular microcirculation, such as IOPs and older age. Thus, looking into the deep vascular layer using OCTA could identify risk factors related to the disturbance in ocular microcirculation.

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Optical Coherence Tomography and Pattern Electroretinography Changes in Egyptian Patients with Major Depressive Disorder

QJM ◽

10.1093/qjmed/hcab109.023 ◽

2021 ◽

Vol 114 (Supplement_1) ◽

Author(s):

Mostafa S ElShaarawi ◽

Ayman A Gaafar ◽

Hisham S. Saad Eldin ◽

Randa H Ali

Keyword(s):

Optical Coherence Tomography ◽

Major Depressive Disorder ◽

Depressive Disorder ◽

Control Group ◽

Ophthalmological Examination ◽

Optical Coherence ◽

Fiber Layer ◽

Major Depressive ◽

Cross Sectional ◽

Pattern Electroretinography

Abstract Background Major depressive disorder (MDD) is a common psychiatric disorder that affects nearly 11.1-14.6 % of the population in their lifetime. Pathophysiology and brain imaging findings show that degenerative and inflammatory processes may play a role. Meta-analysis of voxel-based morphometry studies in MDD demonstrated significant gray matter loss. From anatomical and embryological perspectives, the retina can be considered a unique extension of the brain and is able to reflect axonal histopathology. Being unmyelinated, it can provide insight into the pathophysiological processes of diseases with a neurodegenerative element. Aim to compare retinal optical coherence tomography (OCT) parameters in a group of MDD patients with a healthy control group and to correlate OCT parameters with pattern electroretinography (PERG) parameters. Method a controlled cross sectional study was conducted on 30 MDD patients and 28 age and sex matched controls. Both groups had a full ophthalmological examination, OCT imaging and 7 patients and 11 controls have PERG recorded. Results Thinning of the superior retinal nerve fiber layer, thinning of most of the ganglion cell inner plexiform (GCIP) layer, thinning of most of the macular thickness and thinning of macular volume in both eyes were detected. There was a statistically significant positive correlation between the left GCIP layer and the amplitude of the N95 wave. Also a statistically significant negative correlation existed between MDD duration in years with the left eye's average volume of the outer ring of the macula. Conclusion Significant retinal changes were detected by OCT in MDD patients supporting the theory of neurodegeneration as a pathophysiology of MDD.

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Peripapillary microvasculature in patients with diabetes mellitus: An optical coherence tomography angiography study

Scientific Reports ◽

10.1038/s41598-019-52354-8 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 7

Author(s):

Yong-Il Shin ◽

Ki Yup Nam ◽

Seong Eun Lee ◽

Min-Woo Lee ◽

Hyung-Bin Lim ◽

...

Keyword(s):

Diabetes Mellitus ◽

Optical Coherence Tomography ◽

Optical Coherence Tomography Angiography ◽

Plexiform Layer ◽

Control Group ◽

Diabetic Patients ◽

Inner Plexiform Layer ◽

Optical Coherence ◽

Regression Analyses ◽

Fiber Layer

Abstract To evaluate changes in peripapillary microvascular parameters in diabetes mellitus (DM) patients using optical coherence tomography angiography (OCTA). Seventy-one diabetic patients (40 in the no diabetic retinopathy [DR] group and 31 in the non-proliferative DR [NPDR] group) and 50 control subjects. OCTA (Zeiss HD-OCT 5000 with AngioPlex) 6 × 6 mm scans centered on the optic disc were analyzed. Peripapillary vessel density (VD), perfusion density (PD) in superficial capillary plexus (SCP) were automatically calculated. The average macular ganglion cell-inner plexiform layer (mGC-IPL) and peripapillary retinal nerve fiber layer (pRNFL) thicknesses of the no DR and NPDR groups were significantly thinner than those of the control group. The no DR and NPDR groups showed lower peripapillary VD and PD in SCP compared with the control group. Using univariate regression analyses, the average mGC-IPL thickness, the pRNFL thickness, the no DR group and NPDR group were significant factors that affected the peripapillary VD and PD in SCP. Multivariate regression analyses showed that the grade of DR was a significant factor affecting the peripapillary VD and PD in SCP. OCTA revealed that peripapillary microvascular parameters in the no DR and NPDR groups were lower than those of normal controls. The peripapillary VD and PD in SCP were correlated with the mGC-IPL thickness, the pRNFL thickness, and the no DR and NPDR groups. Changes in peripapillary OCTA parameters may help with understanding the pathophysiology of DM and evaluating a potentially valuable biomarker for patients with subclinical DR.

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A Normative Database of A-Scan Data Using the Heidelberg Spectralis Spectral Domain Optical Coherence Tomography Machine

10.1101/2021.02.16.21251860 ◽

2021 ◽

Author(s):

Joos Meyer ◽

Roshan Karri ◽

Helen Danesh-Meyer ◽

Kate Drummond ◽

Andrew Symons

Keyword(s):

Optical Coherence Tomography ◽

Reference Values ◽

Age Groups ◽

Plexiform Layer ◽

Retinal Nerve Fibre Layer ◽

Inner Plexiform Layer ◽

Optical Coherence ◽

Cross Sectional ◽

Normative Database ◽

The Mean

AbstractPurposeDevelop the first normative database of macular and circumpapillary scans with reference values at the level of the A-scan using the Heidelberg Spectralis Optical Coherence Tomography (OCT) machine.MethodsThis study is a retrospective cross sectional analysis of macular and circumpapillary OCT scans of healthy individuals. All participants had a full ophthalmic examination, including best corrected visual acuity, intraocular pressure, biomicroscopy, posterior segment examination and OCT scan. The volume and thickness of each of the nine Early Treatment Diabetic Retinopathy zones at the macula were analysed for the total retinal thickness, retinal nerve fibre layer (RNFL), ganglion cell layer (GCL) and inner plexiform layer (IPL). The thickness of the circumpapillary RNFL was analysed at the disc. De-identified A-scans were extracted from the OCT machine as separate tab-separated text file and made available according to the data sharing statement.ResultsTwo-hundred eyes from 144 participants were included of which 98 (49%) were female. The mean age (SD) was 48.52 (17.52). Participants were evenly distributed across four age groups and represented nine broad ethnic groups in proportions comparable to the local distribution. All the macular scans were 20° x 20° (5.9 mm x 5.9 mm), with a total scan density between 12,800 and 49,152 A-scans. The peripapillary scans were all 12° (3.5 mm), at a scan density of 768 A-scans. The mean retinal, GCL and IPL volumes were significantly greater in males than females. Age and total retinal volume (r = –0.2561), GCL volume (– 0.2911) and IPL volume (–0.3194) were negatively correlated. No significant correlation was found between the RNFL and age.ConclusionThis study provides a normative database of macular and circumpapillary scans with reference values at the level of the A-scan using the Heidelberg Spectralis Optical Coherence Tomography (OCT) machine.

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Optical Coherence Tomography and Optical Coherence Tomography Angiography Findings After Optic Neuritis in Multiple Sclerosis

Frontiers in Neurology ◽

10.3389/fneur.2020.618879 ◽

2020 ◽

Vol 11 ◽

Author(s):

Olwen C. Murphy ◽

Grigorios Kalaitzidis ◽

Eleni Vasileiou ◽

Angeliki G. Filippatou ◽

Jeffrey Lambe ◽

...

Keyword(s):

Multiple Sclerosis ◽

Optical Coherence Tomography ◽

Optic Neuritis ◽

Visual Function ◽

Inner Plexiform Layer ◽

Optical Coherence ◽

Cross Sectional ◽

Mixed Effect ◽

Retinal Microvasculature ◽

History Of

Background: In people with multiple sclerosis (MS), optic neuritis (ON) results in inner retinal layer thinning, and reduced density of the retinal microvasculature.Objective: To compare inter-eye differences (IEDs) in macular optical coherence tomography (OCT) and OCT angiography (OCTA) measures in MS patients with a history of unilateral ON (MS ON) vs. MS patients with no history of ON (MS non-ON), and to assess how these measures correlate with visual function outcomes after ON.Methods: In this cross-sectional study, people with MS underwent OCT and OCTA. Superficial vascular plexus (SVP) density of each eye was quantified using a deep neural network. IEDs were calculated with respect to the ON eye in MS ON patients, and with respect to the right eye in MS non-ON patients. Statistical analyses used mixed-effect regression models accounting for intra-subject correlations.Results: We included 43 MS ON patients (with 92 discrete OCT/OCTA visits) and 14 MS non-ON patients (with 24 OCT/OCTA visits). Across the cohorts, mean IED in SVP density was −2.69% (SD 3.23) in MS ON patients, as compared to 0.17% (SD 2.39) in MS non-ON patients (p = 0.002). When the MS ON patients were further stratified according to time from ON and compared to MS non-ON patients with multiple cross-sectional analyses, we identified that IED in SVP density was significantly increased in MS ON patients at 1–3 years (p = < 0.001) and >3 years post-ON (p < 0.001), but not at <3 months (p = 0.21) or 3–12 months post-ON (p = 0.07), while IED in ganglion cell + inner plexiform layer (GCIPL) thickness was significantly increased in MS ON patients at all time points post-ON (p ≦ 0.01 for all). IED in SVP density and IED in GCIPL thickness demonstrated significant relationships with IEDs in 100% contrast, 2.5% contrast, and 1.25% contrast letter acuity in MS ON patients (p < 0.001 for all).Conclusions: Our findings suggest that increased IED in SVP density can be detected after ON in MS using OCTA, and detectable changes in SVP density after ON may occur after changes in GCIPL thickness. IED in SVP density and IED in GCIPL thickness correlate well with visual function outcomes in MS ON patients.

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Association of Myopia With Microvascular Alterations in Patients With Type 2 Diabetes: An Optical Coherence Tomography Angiography Study

Frontiers in Medicine ◽

10.3389/fmed.2021.715074 ◽

2021 ◽

Vol 8 ◽

Author(s):

Xin Wen ◽

Zijing Li ◽

Jianhui Xiao ◽

Xuane Liu ◽

Yichi Zhang ◽

...

Keyword(s):

Type 2 Diabetes ◽

Optical Coherence Tomography ◽

Optical Coherence Tomography Angiography ◽

Cross Sectional Study ◽

Vessel Density ◽

Diabetic Patients ◽

Optical Coherence ◽

Fiber Layer ◽

Cross Sectional

Purpose: To determine the association of myopia with peripapillary and macular microvasculature in eyes with type 2 diabetes using optical coherence tomography angiography (OCTA).Methods: Diabetic patients with and without diabetic retinopathy (DR) were recruited and grouped according to myopic status in this cross-sectional study. Axial length, refractive error, and OCTA parameters were measured. OCTA parameters were analyzed with adjustment of confounding factors and further Bonferroni analysis was performed to determine the differences in multiple group comparisons.Results: Compared with the diabetic eyes without myopia, those with myopia had lower rate of DR (21.82 vs. 35.90%, χ2 = 6.190, P = 0.013), longer axial lengths (24.94 ± 0.75 vs. 23.16 ± 0.64, F = 311.055, P < 0.001) and reduced whole vessel density (VD) of optic nerve head (ONH) (45.89 ± 5.76 vs. 49.14 ± 4.33, F = 19.052, P < 0.001), peripapillary VD (48.75 ± 6.56 vs. 50.76 ± 4.51, F = 7.600, P = 0.006), and reduced thickness of the retinal nerve fiber layer (RNFL) (95.50 ± 12.35 vs. 100.67 ± 13.68, F = 5.020, P = 0.026). In eyes without myopia, the superficial vessel density (SVD) (46.58 ± 4.90 vs. 43.01 ± 4.25; 95% CI, 1.80–4.61; P < 0.001), deep vessel density (DVD) (45.64 ± 6.34 vs. 42.15 ± 6.31; 95% CI, 1.07–5.00; P < 0.001), and FD300 area density (50.31 ± 5.74 vs. 44.95 ± 6.96; 95% CI, 2.88–7.27; P < 0.001) were significant reduced in eyes with DR(DR eyes) comparing to those without DR (NoDR eyes). In eyes with myopia, only SVD were significantly reduced in DR eyes comparing to NoDR eyes (41.68 ± 3.34 vs. 45.99 ± 4.17; 95% CI, 1.10–7.22; P = 0.002). In NoDR eyes, both whole VD of ONH and Peripapillary VD demonstrated a significant decrease in eyes with myopia comparing to those without myopia (49.91 ± 4.36 vs. 45.61 ± 6.32; 95% CI, 1.95–6.27; P < 0.001 and 51.36 ± 4.24 vs. 48.52 ± 6.99; 95% CI, 0.56–5.11; P = 0.006, respectively).Conclusions: In diabetic patients, myopic eyes exhibited lower prevalence of DR and thinner thickness of RNFL. The refractive status could possibly impact the retinal microvascular changes from NoDR to DR stage.

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Changes in the Retinal Microvasculature Measured Using Optical Coherence Tomography Angiography According to Age

Journal of Clinical Medicine ◽

10.3390/jcm9030883 ◽

2020 ◽

Vol 9 (3) ◽

pp. 883 ◽

Cited By ~ 2

Author(s):

Seung Hun Park ◽

Heeyoon Cho ◽

Sun Jin Hwang ◽

Beomseo Jeon ◽

Mincheol Seong ◽

...

Keyword(s):

Optical Coherence Tomography ◽

Foveal Avascular Zone ◽

Vascular Density ◽

Inner Plexiform Layer ◽

Optical Coherence ◽

Cross Sectional ◽

Swept Source ◽

Age Related ◽

Retinal Microvasculature ◽

Significant Difference

In this cross-sectional study, we examined age-related changes in the retinal vessels of 100 healthy participants, aged from 5 to 80 years, and divided into four groups (G1, under 20 years of age; G2, from 20 to 39 years of age; G3, from 40 to 59 years of age; G4, age 60 years or older). All subjects underwent swept-source optical coherence tomography (SS-OCT) and OCT angiography (OCTA). The vascular density (VD) of the superficial (SCP) and deep capillary plexus (DCP), and choriocapillaris (CCP) were measured using OCTA. The vascular density of each capillary layer, foveal avascular zone (FAZ) area, ganglion cell-inner plexiform layer (GC-IPL) thickness, retinal thickness (RT), and choroidal thickness (CT) were compared between age groups. Most OCT variables were correlated with OCTA variables. The FAZ area; VD of the SCP, DCP, and CCP; GC-IPL thickness; RT; and CT showed significant difference (p < 0.001) between G1 + G2 and G3 + G4, except for central GC-IPL thickness (p = 0.14) and central RT (p = 0.25). Density of the retinal capillary vasculature reduced and FAZ area increased after age 40, which represents the onset of middle age.

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Effect of Hemodialysis on Anterior Chamber Angle Measured by Anterior Segment Optical Coherence Tomography

Journal of Ophthalmology ◽

10.1155/2019/2406547 ◽

2019 ◽

Vol 2019 ◽

pp. 1-6

Author(s):

Yong Un Shin ◽

Ji Hong Kim ◽

Heeyoon Cho ◽

Dae Sung Kim ◽

Joo-Hark Yi ◽

...

Keyword(s):

Optical Coherence Tomography ◽

Anterior Chamber ◽

Anterior Segment ◽

Posterior Pole ◽

Wide Field ◽

Inner Plexiform Layer ◽

Optical Coherence ◽

Anterior Chamber Angle ◽

Fiber Layer ◽

Chamber Angle

Purpose. To investigate the effect of hemodialysis (HD) on the anterior chamber angle by anterior segment optical coherence tomography (ASOCT) and other ophthalmologic parameters in patients with end-stage kidney disease (ESKD). Methods. A prospective observational study was performed on 20 patients who underwent HD for ESKD. Anterior chamber angle images were obtained by 16 mm line scan of ASOCT. The angle opening distance (AOD) and the trabecular-iris space area (TISA) were determined using the ImageJ program. Additional 12 mm horizontal and 9 mm vertical wide-field scans centered on the posterior pole were performed for the measurement of peripapillary retinal nerve fiber layer (pRNFL) thickness and macular ganglion cell-inner plexiform layer (mGCIPL) thickness. Changes in intraocular pressure (IOP), AOD, TISA, pRNFL thickness, and mGCIPL thickness before and after HD were statistically analyzed. Results. The IOP decreased significantly from 17.5 ± 3.4 before HD to 16.2 ± 2.3 after HD (P=0.017). There was a statistically significant decrease in AOD 750 and TISA 750 (P=0.005 and P=0.007, respectively). AOD 500 and TISA 500 also decreased, which was almost statistically significant (P=0.061 and P=0.081, respectively). Mean pRNFL thickness and mGCIPL thickness did not show significant change after HD. Conclusion. We observed a significant decrease in IOP and anterior chamber angle measurements after HD. Our study suggests that HD can influence the anterior segment structure of eyes.

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