scholarly journals Retinal Vasculature and Microstructure in Early Dry-Type Myopic Maculopathy

2019 ◽  
Vol 2019 ◽  
pp. 1-8
Author(s):  
Jiao Sun ◽  
Jialin Wang ◽  
Yanling Wang
Keyword(s):  
Logistic Regression ◽  
Refractive Error ◽  
Choroidal Thickness ◽  
Retinal Vessel ◽  
Vessel Density ◽  
Retinal Vasculature ◽  
Capillary Plexus ◽  
Group 2 ◽  
Myopic Maculopathy ◽  
Group 1

Purpose. The aim of this cross-sectional study was to characterize and compare the retinal vasculature and microstructure in patients with early dry-type myopic maculopathy. Methods. Patients with a refractive error of less than −6 diopters were enrolled and classified into two groups. Group 1 comprised 82 eyes with a tessellated fundus, and group 2 comprised 56 eyes with diffuse chorioretinal atrophy (DCA). The clinical characteristics, refractive error, axial length, retinal vessel density of the superficial capillary plexus (SCP) and deep capillary plexus (DCP), macular choroidal thickness, and best-corrected visual acuity (BCVA), were compared between the groups. Logistic regression was used to determine the protective and risk factors for DCA. Results. Group 1 patients were significantly younger and had better BCVA, less myopia, and shorter axial length than group 2 patients. The vessel densities of the SCP and DCP, choroidal thickness, retinal nerve fiber layer thickness, ganglion cell complex thickness, and retinal thickness were reduced in group 2. Multiple logistic regression analysis revealed that the vessel densities of the SCP and DCP were protective factors for DCA. Conclusions. The vessel density of the SCP had the highest diagnostic value (sensitivity = 78.0% and specificity = 96.6%). When the SCP vessel density was reduced to ≤49.98%, DCA was indicated. The retinal vessel densities of the SCP and DCP and parameters of the microstructure were reduced significantly in patients with DCA. Vessel density may be a better diagnostic indicator of the development of DCA.

Evaluation of choroidal thickness in light-coloured eyes

2021 ◽  
pp. 112067212110294
Author(s):  
Esra Vural ◽  
Leyla Hazar ◽  
Mehtap Çağlayan ◽  
Ali Rıza Cenk Çelebi
Keyword(s):  
Refractive Error ◽  
Choroidal Thickness ◽  
Healthy Individuals ◽  
Factors Affecting ◽  
The Mean ◽  
Group 2 ◽  
Healthy Participants ◽  
Disease Free ◽  
Group 1 ◽  
Iris Colour

Objective: The aim of this study was to determine whether iris colour is related to the choroidal thickness of healthy individuals. Methods: Healthy participants were divided into two groups. Group 1 had light-coloured eyes (blue and green), and group 2 had dark-coloured eyes (brown). The main outcome measures were iris thickness, subfoveal choroidal thickness and nasal and temporal choroidal thicknesses 500 µm away from the fovea. Results: Group 1 comprised 31 subjects with light-coloured eyes, and group 2 had 31 subjects with dark eyes. The mean ages of groups 1 and 2 were 26.7 ± 7.5 years and 24.1 ± 5.8 years, respectively ( p = 0.14). The choroidal thicknesses of the subfoveal, nasal and temporal regions were 336.3 ± 52.1 µm, 321.9 ± 43.6 µm and 318.4 ± 49.2 µm, respectively, in group 1 and 396.5 ± 76.9 µm, 372 ± 79.3 µm and 379.6 ± 82.4 µm, respectively, in group 2. All the values in group 1 were statistically lower than those in group 2 ( p = 0.001, p = 0.001 and p = 0.003, respectively). The iris thickness in group 1 (493.73 ± 95.44 µm) was thinner than in group 2 (524.61 ± 69.74 µm) but not statistically significant ( p = 0.141). Conclusion: The results showed that a thinner choroid can be seen in disease-free light-coloured eyes. The iris colour should be considered among the factors affecting the choroidal thickness, such as age, sex, race and refractive error.

scholarly journals Retinal and Choriocapillary Vascular Changes in Early Stages of Multiple Sclerosis: A Prospective Study

2021 ◽  
Vol 10 (24) ◽  
pp. 5756
Author(s):  
Daniela Montorio ◽  
Roberta Lanzillo ◽  
Antonio Carotenuto ◽  
Maria Petracca ◽  
Marcello Moccia ◽  
...  
Keyword(s):  
Multiple Sclerosis ◽  
Retinal Vessel ◽  
Vessel Density ◽  
Ganglion Cell Complex ◽  
Healthy Controls ◽  
Fiber Layer ◽  
Density Reduction ◽  
Capillary Plexus ◽  
Retinal Vessel Density ◽  
A Prospective Study

Optical Coherence Tomography Angiography (OCTA) abnormalities occur in multiple sclerosis (MS) over the course of the disease. OCTA investigations at early MS stages are lacking. We aimed to investigate vessel density in macular and papillary regions over two years after an initial demyelinating event (IDE). Vessel density was analyzed in superficial, deep, choriocapillaris and radial peripapillary plexus at baseline, and after one and two years. We also evaluated structural OCT parameter changes of the ganglion cell complex (GCC) and retinal nerve fiber layer (RNFL). We evaluated 30 eyes from 15 IDE patients (7 females, 8 males, mean age 28.4 ± 9.6 years) and 30 eyes from 15 healthy controls. After 2 years, we reported in the IDE group a reduced vessel density in the superficial capillary plexus, deep capillary plexus and radial peripapillary capillary plexus with respect to the baseline (coeff. β = −2.779, p = 0.013; coeff. β = −4.055, p = 0.018 and coeff. β = −2.687, p ≤ 0.001; respectively), while GCC and RNFL thicknesses did not change. Vessel density reduction was not associated with an expanded disability status scale (EDSS) change, relapse occurrence or magnetic resonance imaging activity. The analysis of healthy controls did not reveal any impairment in OCT and OCTA parameters over 2 years of follow-up. Retinal vascular loss occurs in patients with an IDE independently from clinical and radiological disease activity. Retinal vessel density could represent a novel early biomarker to monitor the MS pathological burden.

scholarly journals The Difference in Repeatability of Automated Superficial Retinal Vessel Density according to the Measurement Area Using OCT Angiography

2020 ◽  
Vol 2020 ◽  
pp. 1-9
Author(s):  
Hyung Bin Lim ◽  
Tae Seen Kang ◽  
Yeo Kyoung Won ◽  
Jung Yeul Kim
Keyword(s):  
Intraclass Correlation ◽  
Retinal Vessel ◽  
Vessel Density ◽  
Foveal Avascular Zone ◽  
Capillary Plexus ◽  
The Difference ◽  
Retinal Vessel Density ◽  
Perfusion Density ◽  
Measurement Area ◽  
Central Fovea

Purpose. To evaluate the difference in the repeatability of automated superficial retinal vessel density and foveal avascular zone (FAZ) metrics according to the measurement area of optical coherence tomography angiography (OCTA). Methods. A total of 127 normal eyes from 127 healthy subjects were included. Macular angiography images were acquired from all subjects using the Zeiss Cirrus 5000 with AngioPlex™ OCTA software. Scans of 3 × 3 mm and 6 × 6 mm were each performed twice in a randomly arranged sequence. Vessel density (VD), perfusion density (PD), and FAZ metrics of the superficial capillary plexus were calculated automatically for all scans, and the repeatabilities for both scan patterns were assessed based on intraclass correlation (ICC), coefficient of variation (CV), and coefficient of repeatability (CR) parameters. The average measured values in the two scan patterns were also compared. Results. VD was significantly greater in the 3 × 3 mm scan than in the 6 × 6 mm scan according to all parameters, whereas PD was significantly less in the 3 × 3 mm scan than in the 6 × 6 mm scan. The ICCs for VDs in the central fovea were 0.826 and 0.741 for the 3 × 3 and 6 × 6 mm scans, respectively, and the CVs were 8.00% and 12.75%. For PDs, the ICCs were 0.839 and 0.762 and the CVs were 9.32% and 14.90%. The FAZ metrics in the 3 × 3 mm scan showed good repeatability with an ICC >0.75 and a CV <10.0%. However, all ICCs for the 6 × 6 mm scans were <0.75, and the CVs were all >10%. Conclusions. The 6 × 6 mm macular angiography scans resulted in lower repeatabilities than the 3 × 3 mm scans according to all OCTA parameters, particularly in the central fovea and FAZ metrics. The 3 × 3 mm scan was more suitable than the 6 × 6 mm scan for analyzing macular microvascular density and FAZ metrics.

D-Dimer, P-Selectin, and Microparticles: Novel Markers To Predict Deep Venous Thrombosis.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 2607-2607 ◽  
Author(s):  
John E. Rectenwald ◽  
Daniel D. Myers ◽  
Angela E. Hawley ◽  
Marisa J. Linn ◽  
Chathen R. Gangireddy ◽  
...  
Keyword(s):  
Flow Cytometry ◽  
Logistic Regression ◽  
Venous Thrombosis ◽  
Logistic Regression Model ◽  
Group 3 ◽  
Soluble P ◽  
Group 2 ◽  
Dichotomous Variables ◽  
D Dimer ◽  
Group 1

Abstract The diagnosis of deep venous thrombosis (DVT) is mostly dependent upon duplex ultrasound (DUS) examination of the affected extremity. Data from our laboratory implicates P-Selectin and microparticles (MPs) in the pathogenesis of venous thrombosis. A prospective study was performed to determine the sensitivity and specificity of plasma assays for D-Dimer, soluble P-selectin (P-selectin), and total MPs in patients with documented DVT by DUS. Three groups of individuals were examined: Group 1, 30 normal volunteers; Group 2, 22 patients positive for DVT on DUS (DVT); and Group 3, 21 patients with symptoms of leg pain but negative DUS for DVT (SMP). D-Dimer was measured by the Advanced D-Dimer assay (Dade-Behring, Deerfield, IL), P-Selectin was measured by ELISA (R&D, Minneapolis, MN.) and MPs were assayed by flow cytometry. Total MPs are cell fragments detected by anti-CD41 and anti-CD11b that are &lt; 1 micron, as seen on flow cytometry. Group 1 individuals have D-Dimer levels of 1.53±0.12 mg/dl, P-Selectin of 0.34±0.05 ng/mg total protein (TP), and total MP of 370,103±41,910 particles/200 microliters of platelet-poor plasma. No differences in age (mean=48 vs. 51 yrs, respectively), weight, BMI, use of OCP/HRT, smoking, family history of DVT, or trauma history were noted between DVT and SMP patients. Patients with DVT were more likely to have traveled recently or have a malignancy present. 100% of DVT patients were at highest risk (score≥5) for thrombosis by thrombosis risk assessment (Caprini, JA, J. Thromb. Thrombolysis, 9:253, 2000) while only 62% of SMP patients were at highest risk. Group 2 individuals (DVT) have D-Dimer values of 8.20±2.03 mg/dl, P-Selectin of 0.98±0.11 ng/mg TP, and MPs 129±17% of control. Group 3 individuals (SMP) have D-Dimer values of 3.12±0.79 mg/dl, P-Selectin of 0.55±0.08 ng/mg TP, and MPs 99±12% of control. Differences were statistically significant between groups 2 and 3 for D-Dimer (p=0.01) and P-selectin (p&lt;0.01), while not significantly different for MP (p=0.18). Using a logistic regression model with dichotomous variables, we determined a sensitivity of 73%, a specificity of 81%, and an accuracy of 77% when combining D-Dimer, soluble P-selectin, and total MPs to differentiate DVT from SMP patients. The single variable most predictive for thrombosis was soluble P-Selectin. Logistic Regression Analysis Using Dichotomous Variables. Variables Threshold Value Sensitivity Specificity Accuracy D-Dimer 3 mg/dl 64% 76% 70% Soluble P-Selectin 0.68 ng/ml TP 68% 81% 74% Total Microparticles 125% (compared to controls) 50% 67% 58% Combined Variables 73% 81% 77% A logistic regression model using continuous variables yielded similar results and was statistically significant (p=0.05) to distinguish DVT from SMP patients. This study demonstrates that combined plasma assays for venous thrombosis markers achieve moderate sensitivity and specificity in differentiating DVT from SMP patients. It also suggests that P-Selectin participates in the pathophysiology of DVT. More studies with larger numbers of patients are planned to confirm this assessment.

scholarly journals Differential Treatment of Nerve Root Compression Pain Caused by Lumbar Disc Herniation Applying Nucleoplasty

2010 ◽  
Vol 5;13 (5;9) ◽  
pp. 469-480
Author(s):  
Andrey Bokov
Keyword(s):  
Logistic Regression ◽  
Disc Herniation ◽  
Logistic Regression Model ◽  
Nerve Root Compression ◽  
Disc Protrusion ◽  
Group 3 ◽  
Group 2 ◽  
Clinically Significant ◽  
Disc Extrusion ◽  
Group 1

Background: Nucleoplasty is a minimally invasive intervention use to perform disc decompression in cases of nerve root compression caused by disc herniation. It is important to find rational guidelines for choosing between nucleoplasty and microsurgery. Objective: To analyze factors that may impact the results of nucleoplasty, and to validate the rational guidelines between minimally invasive treatment and open surgery. Study Design: Prospective, non-randomized, cohort study with a minimal follow-up period of 18 months. Methods: Patients were given a neurological examination, visual analogue scale and Oswestry disability questionnaire, obligatory MRI, optional RCT, and discography, only before nucleoplasty. Patients have been divided into the following groups: Group 1 – patients with a disc protrusion treated with nucleoplasty (n = 46), which has been divided into Subgroup 1A, those with a disc protrusion size ≤ 5 mm (n = 24), and Subgroup 1B, those with a disc protrusion size 6 – 9 mm (n = 22); Group 2 – patients with a disc extrusion treated with nucleoplasty (n = 27); Group 3 – patients with a disc extrusion or sequester treated with microdiscectomy (n = 65). Outcome Measures: Clinically significant outcomes were a 50% relief of pain intensity and a 40% decrease of Oswestry Disability Index (ODI). Results: A decrease of pain intensity and disability was found in all groups of patients, P < 0.0001; SP (statistical power) = 99 – 100%. Subgroups 1A and 1B showed no clinically significant differences in outcome, P = 0.99; SP = 5.3. Clinically significant results: Group 1 – 78%; 95% CI (confidence interval) [66; 90%], Group 2 – 44%; 95% CI [25; 65%], Group 3 – 93%; 95% CI [85; 98%]. Total annulus disruption increases the rate of unsatisfactory results of nucleoplasty, OR (odds ratio) = 4.5; 95% CI [1.57; 12.87] (logistic regression model, P = 0.0034). Nucleoplasty performed in cases of uncontained disc herniation (disc extrusion) have a significantly higher rate of unsatisfactory results versus microdiscectomy, OR = 19.06; 95% CI [2.29; 68.73] (logistic regression model, P < 0.0001). Limitations: This study was limited by the small number of patients in each group. Conclusion: The size of the disc protrusion does not significantly affect the outcome of nucleoplasty. The rational guideline for choosing between the 2 types of surgery is the integrity of the annulus. Key words: disc herniation, nucleoplasty, microdiscectomy, annulus integrity

scholarly journals Quantification of Optical Coherence Tomography Angiography in Age and Age-related Macular Degeneration using Vessel Density analysis

2019 ◽  
Author(s):  
Ehsan Vaghefi ◽  
Sophie Hill ◽  
Hannah M Kersten ◽  
David Squirrell
Keyword(s):  
Optical Coherence Tomography ◽  
Macular Degeneration ◽  
Optical Coherence Tomography Angiography ◽  
Retinal Vessel ◽  
Vessel Density ◽  
Age Related Macular Degeneration ◽  
Optical Coherence ◽  
Age Related ◽  
Capillary Plexus ◽  
Retinal Vessel Density

AbstractPurposeTo determine whether vessel density (VD) as measured by optical coherence tomography angiography (OCT-A) provide insights into retinal and choriocapillaris vascular changes with ageing and intermediate dry age related macular degeneration (AMD).MethodsSeventy-five participants were recruited into three cohorts; young healthy (YH) group, old healthy (OH) and those at high-risk for exudative AMD. Raw OCT and OCT-A data from TOPCON DRI OCT Triton were exported using Topcon IMAGENET 6.0 software, and 3D datasets were analysed to determine retinal thickness and vessel density.ResultsCentral macular thickness measurements revealed a trend of overall retinal thinning with increasing age. VD through the full thickness of the retina was highest in ETDRS sector 4 (the inferior macula) in all the cohorts. Mean VD was significantly higher in the deep capillary plexus than the superficial capillary plexus in all ETDRS sectors in all cohorts but there was no significant difference noted between groups. Choriocapillaris VD was significantly lower in all ETDRS sectors in the in the AMD group compared with the YH and the OH groups.ConclusionsRetinal vessel density maps, derived from the retinal plexi are not reliable biomarkers for assessing the ageing macular. Our non-proprietary analysis of the vascular density of the choriocapillaris revealed a significant drop off of VD with age and disease but further work is required to corroborate this finding. If repeatable, choriocapillaris VD may provide a non-invasive biomarker of healthy ageing and disease.Brief SummaryIn this manuscript, we have studied the potential of retinal vessel density as measured by optical coherence tomography angiography (OCT-A), as a biomarker for detection of high-risk of developing exudative age-related macular degeneration (AMD).

Refractive Error in Patients with Retinopathy of Prematurity after Laser Photocoagulation or Bevacizumab Monotherapy

2015 ◽  
Vol 234 (4) ◽  
pp. 211-217 ◽  
Author(s):  
Hsi-Kung Kuo ◽  
I-Ting Sun ◽  
Mei-Yung Chung ◽  
Yi-Hao Chen
Keyword(s):  
Refractive Error ◽  
Retinopathy Of Prematurity ◽  
Laser Photocoagulation ◽  
Group 4 ◽  
Group 3 ◽  
The Mean ◽  
Group 2 ◽  
Type 1 Rop ◽  
Group 1

Purpose: To evaluate the refractive development of premature infants with retinopathy of prematurity (ROP) after treatment with laser photocoagulation or intravitreal injection of bevacizumab (IVB). Methods: The medical records of patients with ROP treated between 2003 and 2012 who underwent yearly follow-ups were retrospectively reviewed. Patients with residual ROP abnormalities were excluded. The cycloplegic refraction at 3 years of age, assessed using an autorefractometer, was recorded. Results: In total, 54 eyes from 54 patients were enrolled. Patients were divided into 4 groups: group 1, including 14 eyes of 14 patients treated with laser therapy; group 2, 15 eyes of 15 patients treated with IVB; group 3, 13 eyes of 13 patients with non-type 1 ROP under conservative follow-up, and group 4, 12 eyes of 12 premature patients without ROP. The mean spherical equivalent at 3 years of age was -1.71 ± 1.27 dpt in group 1, -1.53 ± 2.20 dpt in group 2, 0.63 ± 1.37 dpt in group 3, and 0.41 ± 1.95 dpt in group 4. The mean refractive error differed significantly among the 4 groups (p < 0.001). Patients in groups 1 and 2 were more prone to myopia compared with those in groups 3 and 4. Furthermore, patients with type 1 ROP treated by laser photocoagulation (group 1) and those treated by IVB (group 2) had similar refraction (p = 1). Conclusions: The results of this study suggest that treatment-demanding ROP eyes are susceptible to more severe myopia with age compared with eyes without ROP or those with spontaneously regressed ROP. In addition, the myopic status between laser and IVB treatment did not differ statistically.

scholarly journals Changes in retinal vascular diameters in senior and geriatric cats in association with variation in systemic blood pressure

2021 ◽  
pp. 1098612X2199762
Author(s):  
Andra-Elena Enache ◽  
Ursula M Dietrich ◽  
Oscar Drury ◽  
Emanuele Trucco ◽  
Tom MacGillivray ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Target Organ Damage ◽  
Retinal Vessel ◽  
Systemic Blood Pressure ◽  
Risk Indicator ◽  
Group 4 ◽  
Group 3 ◽  
Group 5 ◽  
Group 2 ◽  
Group 1

Objectives Early diagnosis of arterial hypertension is essential to prevent target organ damage. In humans, retinal arteriolar narrowing predicts hypertension. This blinded prospective observational study investigated the retinal vessel diameters in senior and geriatric cats of varying systolic blood pressure (SBP) status and evaluated retinal vascular changes in hypertensive cats after treatment. Methods Cats with a median age of 14 years (range 9.1–22 years) were categorised into five groups: group 1, healthy normotensive (SBP <140 mmHg; n = 40) cats; group 2, pre-hypertensive (SBP 140–160 mmHg; n = 14) cats; group 3, cats with chronic kidney disease (CKD) and normotensive (n = 26); group 4, cats with CKD and pre-hypertensive (n = 13); and group 5, hypertensive cats (SBP >160 mmHg, n = 15). Colour fundus images (Optibrand ClearView) were assessed for hypertensive lesions. Retinal vascular diameters and bifurcation angles were annotated and calculated using the Vascular Assessment and Measurement Platform for Images of the Retina annotation tool (VAMPIRE-AT). When available, measurements were obtained at 3 and 6 months after amlodipine besylate treatment. Results Ten hypertensive cats had retinal lesions, most commonly intraretinal haemorrhages and retinal exudates. Arteriole and venule diameters decreased significantly with increasing age (–0.17 ± 0.05 pixels/year [ P = 0.0004]; –0.19 ± 0.05 pixels/year). Adjusted means ± SEM for arteriole and venule diameter (pixels) were 6.3 ± 0.2 and 8.9 ± 0.2 (group 1); 7.6 ± 0.3 and 10.1 ± 0.4 (group 2); 6.9 ± 0.2 and 9.5 ± 0.3 (group 3); 7.4 ± 0.3 and 10.0 ± 0.4 (group 4); and 7.0 ± 0.3 and 9.8 ± 0.4 (group 5). Group 1 arteriole and venule diameters were significantly lower than those of groups 2 and 4. Group 2 arteriole bifurcation angle was significantly narrower than those of groups 1 and 3. Post-treatment, vessel diameters decreased significantly at 3 and 6 months in seven hypertensive cats. Conclusions and relevance Increased age was associated with reduced vascular diameters. Longitudinal studies are required to assess if vessel diameters are a risk indicator for hypertension in cats.

scholarly journals Secondary Sutureless Posterior Chamber Lens Implantation with Two Specifically Designed IOLs: Iris Claw Lens versus Sutureless Trans-Scleral Plugs Fixated Lens

2021 ◽  
Vol 10 (10) ◽  
pp. 2216
Author(s):  
Daniel Seknazi ◽  
Donato Colantuono ◽  
Rachid Tahiri ◽  
Francesca Amoroso ◽  
Alexandra Miere ◽  
...  
Keyword(s):  
Visual Acuity ◽  
Refractive Error ◽  
Posterior Chamber ◽  
Secondary Implantation ◽  
Department Of Ophthalmology ◽  
Induced Astigmatism ◽  
Group 2 ◽  
Iris Claw Lens ◽  
Iris Claw ◽  
Group 1

Background. The management of patients with aphakia and/or lack of capsular support remains debated. The sutureless posterior chamber IOL (PCIOL) fixation is a very useful surgical option. The purpose of the study was to compare the early outcomes as well as post-operative best corrected visual acuity, refractive errors and complications of two different techniques of sutureless PCIOL secondary implantation. Methods. Patients who underwent secondary implantation from December 2019 to January 2021 in the Department of Ophthalmology of Creteil Hospital, and in the Granville Ophthalmology Center, were retrospectively included. Eyes implanted with the iris claw lens (Artisan Aphakia IOL model 205, Ophtec BV, Groningen, The Netherlands) were included in group 1, and eyes implanted with a newly developed sutureless trans-scleral plugs fixated lens (STSPFL, Carlevale lens, Soleko, Pontecorvo, Italy) were included in group 2. Results. Twenty-two eyes of 22 patients were enrolled in group 1, and twenty eyes of 20 patients in group 2. No difference was found in visual acuity between two groups (0.35 +/− 0.29 logmar for group 1 and 0.23 +/− 0.51 logmar for group 2) (p = 0.15) at mean post-operative follow up (6.19 +/− 3.44 months for group 1 and 6.42 +/− 3.96 months for group 2) (p = 0.13). Both the mean refractive error (MRE) and induced astigmatism (IA) were greater in group 1 compared to group 2, respectively: the MRE was 0.99 +/− 0.57 vs. 0.46 +/− 0.36 (p < 0.01), and IA was 1.72 +/− 0.96 vs. 0.72 +/− 0.52 (p < 0.01). Conclusions. No significant differences in terms of the recovery of visual acuity were found between the two groups. Group 2 (STPFL) gives better results in our sample due to less post-operative induced astigmatism and less refractive error.

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