56 research outputs found
Ranibizumab in monotherapy and combined with photodynamic therapy for retinal angiomatous proliferation
Purpose: to compare the effects of intravitreal ranibizumab in monotherapy (group A) and combined with photodynamic therapy (PDT) with verteporfin (group B) in retinal angiomatous proliferation (RAP) treatment. Methods: this was a multicentric, prospective, randomized clinical study conducted with parallel groups. The study eye in both groups received ranibizumab on days 1, 30, and 60 (loading dose); group B received PDT additionally on day 1. Early Treatment Diabetic Retinopathy Study (ETDRS) visual acuity (VA) testing and optical coherence tomography were performed monthly, and fluorescein angiography and indocyanine green angiography were performed quarterly. Retreatment criteria were leakage in fluorescein angiography or indocyanine green angiography, mean foveal thickness increase ≥100 µm, or VA decrease ≥5 letters. Results: twenty patients were recruited (ten patients in each group). Six eyes had previous treatment (three eyes in group A and three eyes in group B), so only 14 eyes were naïve. At 12-month follow-up, mean VA improved +1.5 letters in group A and +5.6 letters in group B (analysis of variance test; P>0.05). Two patients (20%) in both groups gained ≥15 letters (chi-square test; P>0.05). Mean changes in greatest linear dimension and in foveal thickness were not statistically significant between groups of treatment (analysis of variance test; P>0.05). Mean retreatments per patient were 1.8 (group A) and 0.9 (group B) (Mann-Whitney U-test; P>0.05). One patient died due to underlying disease not related to study medication. Conclusion: intravitreal ranibizumab administered in monotherapy or combined with PDT was efficacious in terms of VA stabilization in patients with RAP
Automatic segmentation of the Foveal Avascular Zone in ophthalmological OCT-A images
Angiography by Optical Coherence Tomography is a non-invasive retinal imaging
modality of recent appearance that allows the visualization of the vascular
structure at predefined depths based on the detection of the blood movement.
OCT-A images constitute a suitable scenario to analyse the retinal vascular
properties of regions of interest, measuring the characteristics of the foveal
vascular and avascular zones. Extracted parameters of this region can be used
as prognostic factors that determine if the patient suffers from certain
pathologies, indicating the associated pathological degree. The manual
extraction of these biomedical parameters is a long, tedious and subjective
process, introducing a significant intra and inter-expert variability, which
penalizes the utility of the measurements. In addition, the absence of tools
that automatically facilitate these calculations encourages the creation of
computer-aided diagnosis frameworks that ease the doctor's work, increasing
their productivity and making viable the use of this type of vascular
biomarkers.
We propose a fully automatic system that identifies and precisely segments
the region of the foveal avascular zone (FAZ) using a novel ophthalmological
image modality as is OCT-A. The system combines different image processing
techniques to firstly identify the region where the FAZ is contained and,
secondly, proceed with the extraction of its precise contour. The system was
validated using a representative set of 168 OCT-A images, providing accurate
results with the best correlation with the manual measurements of two experts
clinician of 0.93 as well as a Jaccard's index of 0.82 of the best experimental
case. This tool provides an accurate FAZ measurement with the desired
objectivity and reproducibility, being very useful for the analysis of relevant
vascular diseases through the study of the retinal microcirculation
Multimodality imaging approach for combined central retinal vein and artery occlusion: the role of optical coherence tomography angiography
Combined central retinal artery and vein occlusion is an uncommon vascular pathology that can cause severe and permanent visual impairment. Optical coherence tomography angiography (OCTA) is a newly available, noninvasive imaging technique that can potentially improve understanding of the structural and vascular implications and prognosis of this infrequent pathology. The present report describes the principal clinical findings in a case of combined central retinal artery and vein occlusion, as detected by the different imaging modalities available in a tertiary referral hospital. OCTA wide-field montage images identified an extensive area of nonperfusion on the macula with involvement of the entire retina at nearly 360°. We observed the most severe nonperfusion in the deep capillary plexus, while perfusion of the choriocapillaris was unaffected. Meanwhile, fluorescein angiography (FA) findings revealed a delay in perfusion rate with marked nonperfusion areas in the peripheral retina at 360°. We identified that the wide-field OCTA montage permitted visualization of a similar or wider peripheral retinal area compared with FA. Therefore, OCTA is potentially useful for assessment of the global retinal nonperfusion status at baseline and during follow-up, with the added advantage of being a noninvasive techniqueThis work was supported in part by the Mutua Madrileña project (Ref. 2017/365)S
Automatic Visual Acuity Estimation by Means of Computational Vascularity Biomarkers Using Oct Angiographies
[Abstract] Optical Coherence Tomography Angiography (OCTA) constitutes a new non-invasive ophthalmic image modality that allows the precise visualization of the micro-retinal vascularity that is commonly used to analyze the foveal region. Given that there are many systemic and eye diseases that affect the eye fundus and its vascularity, the analysis of that region is crucial to diagnose and estimate the vision loss. The Visual Acuity (VA) is typically measured manually, implying an exhaustive and time-consuming procedure. In this work, we propose a method that exploits the information of the OCTA images to automatically estimate the VA with an accurate error of 0.1713.Instituto de Salud Carlos III; DTS18/00136Ministerio de EconomĂa y Competitividad; DPI2015-69948-RXunta de Galicia; ED431G/01Xunta de Galicia; ED431C 2016-047Ministerio de Ciencia, InnovaciĂłn y Universidades; RTI2018-095894-B-I0
Pachychoroid Diseases of the Macula
Advances in optical coherence tomography have enabled a better appreciation of the role of pathologic choroidal changes in a variety of retinal disease. A “pachychoroid” (pachy-[prefix]: thick) is defined as an abnormal and permanent increase in choroidal thickness often showing dilated choroidal vessels and other structural alterations of the normal choroidal architecture. Central serous chorioretinopathy is just one of several pachychoroid-related macular disorders. This review summarizes the current state of knowledge of the pachycoroid spectrum and the hallmark features seen with multimodal imaging analysis of these entitie
A Novel Automatic Method to Estimate Visual Acuity and Analyze the Retinal Vasculature in Retinal Vein Occlusion Using Swept Source Optical Coherence Tomography Angiography
[Abstract] The assessment of vascular biomarkers and their correlation with visual acuity is one of the most important issues in the diagnosis and follow-up of retinal vein occlusions (RVOs). The high workloads of clinical practice make it necessary to have a fast, objective, and automatic method to analyze image features and correlate them with visual function. The aim of this study is to propose a fully automatic system which is capable of estimating visual acuity (VA) in RVO eyes, based only on information obtained from macular optical coherence tomography angiography (OCTA) images. We also propose an automatic methodology to rapidly measure the foveal avascular zone (FAZ) area and the vascular density (VD) in the superficial and deep capillary plexuses in swept-source OCTA images centered on the fovea. The proposed methodology is validated using a representative sample of 133 visits of 50 RVO patients. Our methodology estimates VA with very high precision and is even more accurate when we integrate depth information, providing a high correlation index of 0.869 with the real VA, which outperforms the correlation index of 0.855 obtained when estimating VA from the data obtained by the semiautomatic existing method. In conclusion, the proposed method is the first computational system able to estimate VA in RVO, with the additional benefits of being automatic, less time-consuming, objective and more accurate. Furthermore, the proposed method is able to integrate depth information, a feature which is lacking in the existing method.Mutua Madrileña; 2017/365
A Novel Automatic Method to Estimate Visual Acuity and Analyze the Retinal Vasculature in Retinal Vein Occlusion Using Swept Source Optical Coherence Tomography Angiography
The assessment of vascular biomarkers and their correlation with visual acuity is one of the most important issues in the diagnosis and follow-up of retinal vein occlusions (RVOs). The high workloads of clinical practice make it necessary to have a fast, objective, and automatic method to analyze image features and correlate them with visual function. The aim of this study is to propose a fully automatic system which is capable of estimating visual acuity (VA) in RVO eyes, based only on information obtained from macular optical coherence tomography angiography (OCTA) images. We also propose an automatic methodology to rapidly measure the foveal avascular zone (FAZ) area and the vascular density (VD) in the superficial and deep capillary plexuses in swept-source OCTA images centered on the fovea. The proposed methodology is validated using a representative sample of 133 visits of 50 RVO patients. Our methodology estimates VA with very high precision and is even more accurate when we integrate depth information, providing a high correlation index of 0.869 with the real VA, which outperforms the correlation index of 0.855 obtained when estimating VA from the data obtained by the semiautomatic existing method. In conclusion, the proposed method is the first computational system able to estimate VA in RVO, with the additional benefits of being automatic, less time-consuming, objective and more accurate. Furthermore, the proposed method is able to integrate depth information, a feature which is lacking in the existing methodThis work has received partial financial support from the Mutua Madrileña project, Ref. 2017/365S
Efficacy and safety of an aflibercept treat-and-extend regimen in treatment-naive patients with macular oedema secondary to central retinal vein occlusion (CRVO): a prospective 12-month, single-arm, multicentre trial
Objectives: to evaluate efficacy and safety of an aflibercept treat-and-extend (TAE) regimen in patients with macular oedema (MO) secondary to central retinal vein occlusion (CRVO). Design setting and patients: phase IV, prospective, open-label, single-arm trial in 11 Spanish hospitals. Treatment-naïve patients with <6 month diagnosis of MO secondary to CRVO and best-corrected visual acuity (BCVA) of 73-24 ETDRS letters were included between 23 January 2015 and 17 March 2016. Intervention: intravitreal aflibercept 2 mg monthly (3 months) followed by proactive individualized dosing. Main outcomes: mean change in BCVA after 12 months. Results: 24 eyes (24 patients) were included; mean (SD) age: 62.8 (15.0) years; 54.2% male; median (IQR) time since diagnosis: 7.6 (3.0, 15.2) days. Mean BCVA scores significantly improved between baseline (56.0 (16.5)) and Month 12 (74.1 (17.6)); mean (95% CI) change: 14.8 (8.2, 21.4); P=0.0001. Twelve (50.0%) patients gained ≥15 ETDRS letters. Foveal thickness improved between baseline (mean: 569.4 (216.8) µm) and Month 12 (mean 257.4 (48.4) µm); P < 0.0001. At Month 12, 8.3% patients had MO. The mean (SD) number of injections: 8.3 (3.0). No treatment-related AEs were reported. Five (20.8%) patients experienced ocular AEs. Two nonocular serious AEs were reported. Conclusions: an aflibercept TAE regimen improves visual acuity in patients with MO secondary to CRVO over 12 months with good tolerability
Individualized Therapy with Ranibizumab in Wet Age-Related Macular Degeneration
Individualized treatment regimens may reduce patient burden with satisfactory patient outcomes in neovascular age-related macular degeneration. Intravitreal anti-VEGF drugs are the current gold standard. Fixed monthly injections offer the best visual outcome but this regimen is not commonly followed outside clinical trials. A PRN regimen requires monthly visits where the patient is treated in the presence of signs of lesion activity. Therefore, an early detection of reactivation of the disease with immediate retreatment is crucial to prevent visual acuity loss. Several trials suggest that 'treat and extend' and other proactive regimens provide a reasonable approach. The rationale of the proactive regimens is to perform treatment anticipating relapses or recurrences and therefore avoid drops in vision while individualizing patient followup. Treat and extend study results in significant direct medical cost savings from fewer treatments and office visits compared to monthly treatment. Current data suggest that, for one year, PRN is less expensive, but treat and extend regimen would likely be less expensive for subsequent years. Once a patient is not a candidate to continue with treatment, he/she should be sent to an outpatient unit with adequate resources to follow nAMD patients in order to reduce the burden of specialized ophthalmologist services
- …