Ultra-widefield Scanning Laser Ophthalmoscope Research Articles

Peripheral Retinal Imaging Biomarkers for Alzheimer’s Disease: A Pilot Study

Purpose: To examine whether ultra-widefield (UWF) retinal imaging can identify biomarkers for Alzheimer’s disease (AD) and its progression. Methods: Images were taken using a UWF scanning laser ophthalmoscope (Optos P200C AF) to determine phenotypic variations in 59 patients with AD and 48 healthy controls at baseline (BL). All living participants were invited for a follow-up (FU) after 2 years and imaged again (if still able to participate). All participants had blood taken for genotyping at BL. Images were graded for the prevalence of age-related macular degeneration-like pathologies and retinal vascular parameters. Comparison between AD patients and controls was made using the Student t test and the χ² test. Results: Analysis at BL revealed a significantly higher prevalence of a hard drusen phenotype in the periphery of AD patients (14/55; 25.4%) compared to controls (2/48; 4.2%) [χ² = 9.9, df = 4, p = 0.04]. A markedly increased drusen number was observed at the 2-year FU in patients with AD compared to controls. There was a significant increase in venular width gradient at BL (zone C: 8.425 × 10^–3 ± 2.865 × 10^–3 vs. 6.375 × 10^–3 ± 1.532 × 10^–3, p = 0.008; entire image: 8.235 × 10^–3 ± 2.839 × 10^–3 vs. 6.050 × 10^–3 ± 1.414 × 10^–3, p = 0.004) and a significant decrease in arterial fractal dimension in AD at BL (entire image: 1.250 ± 0.086 vs. 1.304 ± 0.089, p = 0.049) with a trend for both at FU. Conclusions: UWF retinal imaging revealed a significant association between AD and peripheral hard drusen formation and changes to the vasculature beyond the posterior pole, at BL and after clinical progression over 2 years, suggesting that monitoring pathological changes in the peripheral retina might become a valuable tool in AD monitoring.

A Graph Cut Approach to Artery/Vein Classification in Ultra-Widefield Scanning Laser Ophthalmoscopy.

The classification of blood vessels into arterioles and venules is a fundamental step in the automatic investigation of retinal biomarkers for systemic diseases. In this paper, we present a novel technique for vessel classification on ultra-wide-field-of-view images of the retinal fundus acquired with a scanning laser ophthalmoscope. To the best of our knowledge, this is the first time that a fully automated artery/vein classification technique for this type of retinal imaging with no manual intervention has been presented. The proposed method exploits hand-crafted features based on local vessel intensity and vascular morphology to formulate a graph representation from which a globally optimal separation between the arterial and venular networks is computed by graph cut approach. The technique was tested on three different data sets (one publicly available and two local) and achieved an average classification accuracy of 0.883 in the largest data set.

Non-contact ultra-widefield retinal imaging of infants with suspected abusive head trauma

PurposeThe purpose of the study was to audit the use of non-contact ultra-widefield retinal imaging in infants with suspected abusive head trauma (AHT) using the Optos P200MA Scanning Laser Ophthalmoscope.Patients and methodsA retrospective, observational case series. Ten eyes of five consecutive infants (aged 1-15 months) with suspected (or in 1 case, known) AHT referred for an ophthalmological opinion were included. Each infant underwent non-contact ultra-widefield retinal imaging using the Optos P200MA scanning laser ophthalmoscope. Optos fundus fluorescein angiography (FFA) was performed in one infant with oral sedation. The other four infants did not require sedation. The main outcome measure was the acquisition of a single, definitive ultra-widefield retinal image in each eye. Safety was audited by determining adverse changes in heart rate and oxygen saturations that required cessation of imaging.ResultsThe Optos P200MA ultra-widefield scanning laser ophthalmoscope acquired good quality retinal images in all infants. Documentation of acute, widespread retinal haemorrhages contributed to a diagnosis of AHT in three infants. Chronic pre-macular haemorrhage and macular schisis were documented by FFA in a fourth infant. The absence of retinal haemorrhages was documented in a fifth infant contributing to the exclusion of a diagnosis of AHT. There were no adverse safety signals in any infant in this series.ConclusionThe Optos P200MA ultra-widefield scanning laser ophthalmoscope appears safe to use in infants with suspected AHT, providing high-quality retinal images in a single frame without ocular contact. Optos P200MA may be used as alternative to RetCam to document retinal haemorrhages in stable infants with suspected AHT.

Clinical and genetic characteristics of Leber congenital amaurosis with novel mutations in known genes based on a Chinese eastern coast Han population.

To study the genotype-phenotype characteristics of Leber congenital amaurosis (LCA) in the Chinese eastern coast Han population. Children with strictly defined LCA with novel mutations of known LCA genes identified by targeted next-generation sequencing (NGS) and a prediction of pathogenicity (in silico) were included in this study (2013-2015). Mutations were confirmed using Sanger sequencing and segregation analysis. The clinical findings were recorded, including visual function, refractive error, fundus changes, and electroretinograms (ERGs). Spectral-domain optical coherence tomography (SD-OCT) examination, fundus fluorescein angiography (FFA), and ultra-wide field scanning laser ophthalmoscopy (UWF SLO) were performed on children when available. A total of 65 patients underwent NGS for mutation screening and 45 patients were identified as carrying known LCA genes. Of these, 36(80%) children harbored novel mutations, and they were all from the eastern coast of China. A total of 50 novel variants were identified, which covered 15 known LCA genes. GUCY2D (17%), CEP290 (14%), NMNAT1 (14%), AIPL1 (11%) and RPGRIP1 (11%) were the five most frequently mutated genes with novel mutations. A total of four (11%) patients with AIPL1 mutations harbored the same novel mutated allele (c.C241T p.Q81X), which was homozygous in patients 1 and 2. Unusual manifestations were detected in patient 16 who had novel mutations in CRB1 with a dense proliferative membrane adhering to the posterior retina of the right eye with numerous fine glistening crystals spreading over the retina of both eyes. Ten (40%) of the 25 available patients who underwent SD-OCT showed a normal macular appearance using fundus photography but an abnormal macular structure using OCT imaging, most of whom presented with a thickened fovea with maldevelopment of the inner and outer retinal laminae. There may be a high frequency of AIPL1 novel mutations and a founder mutation of p.Q81X in the Chinese eastern coast Han population. Our findings of specific features in this population broaden the spectrum of novel mutations and the phenotype of LCA with ethnic and regional variations. Fundus multimodality imaging may help guide comprehensive assessments for patients with LCA.

Optomap ultrawide field imaging identifies additional retinal abnormalities in patients with diabetic retinopathy.

PurposeTo compare diabetic retinopathy (DR) severity grading between Optomap ultrawide field scanning laser ophthalmoscope (UWFSLO) 200° images and an Early Treatment Diabetic Retinopathy Study (ETDRS) seven-standard field view.MethodsOptomap UWFSLO images (total: 266) were retrospectively selected for evidence of DR from a database of eye clinic attendees. The Optomap UWFSLO images were graded for DR severity by two masked assessors. An ETDRS seven-field mask was overlaid on the Optomap UWFSLO images, and the DR grade was assessed for the region inside the mask. Any interassessor discrepancies were adjudicated by a senior retinal specialist. Kappa agreement levels were used for statistical analysis.ResultsFifty images (19%) (P<0.001) were assigned a higher DR level in the Optomap UWFSLO view compared to the ETDRS seven-field view, which resulted in 40 images (15%) (P<0.001) receiving a higher DR severity grade. DR severity grades in the ETDRS seven-field view compared with the Optomap UWFSLO view were identical in 85% (226) of the images and within one severity level in 100% (266) of the images. Agreement between the two views was substantial: unweighted κ was 0.74±0.04 (95% confidence interval: 0.67–0.81) and weighted κ was 0.80±0.03 (95% confidence interval: 0.74–0.86).ConclusionCompared to the ETDRS seven-field view, a significant minority of patients are diagnosed with more severe DR when using the Optomap UWFSLO view. The clinical significance of additional peripheral lesions requires evaluation in future prospective studies using large cohorts.

The Characteristics of Non-Retinal Lesions in the Ultra-Wide Field Scanning Laser Ophthalmoscope Image

The Characteristics of Non-Retinal Lesions in the Ultra-Wide Field Scanning Laser Ophthalmoscope Image

Microaneurysm Turnover in Diabetic Retinopathy Assessed by Automated RetmarkerDR Image Analysis - Potential Role as Biomarker of Response to Ranibizumab Treatment

Purpose: To evaluate the influence of a ranibizumab treatment on microaneurysm (MA) turnover in diabetic retinopathy. Methods: Sixty-nine eyes were included in this retrospective study. We compared a group of 33 eyes with ranibizumab treatment for diabetic macular edema to 36 eyes with nonproliferative diabetic retinopathy only. Nonmydriatic ultra-widefield scanning laser ophthalmoscopy (Optomap) images were obtained at a mean 4.76 ± 1.69 days prior to the first ranibizumab injection (baseline) and again 35.94 ± 2.44 days after the third consecutive injection in a 4-week interval. In untreated controls, images were obtained at baseline and 97.81 ± 3.16 days thereafter. Images were analyzed using the RetmarkerDR software (Critical Health SA, Coimbra, Portugal), and the turnover of MAs was documented and analyzed. Thereafter, MA turnover was correlated with central retinal thickness (CRT) as assessed by OCT. Results: At baseline, patients in the treatment group had 5.64 ± 0.75 MAs. One month after 3 ranibizumab injections, measured MAs decreased to 4.03 ± 0.66. In the untreated control group, the initial number of 3.36 ± 0.6 MAs remained almost unchanged over 3-4 months (2.89 ± 0.57 MAs). Dynamic analysis showed that after ranibizumab treatment 3.06 ± 0.5 new MAs appeared, while 5.09 ± 0.79 disappeared. In the control group, 2.11 ± 0.4 new MAs appeared and 2.61 ± 0.48 disappeared. MA turnover was significantly higher with ranibizumab compared to the control group (8.15 ± 1.14 vs. 4.72 ± 0.81, p < 0.001). Consistently, CRT decreased from 444 to 330 µm in the ranibizumab group, while there was no change in the control group (291 vs. 288 µm). Conclusion: The treatment of macular edema using ranibizumab does not only reduce macular thickness, but also has an impact on the turnover of MAs in diabetic retinopathy. RetmarkerDR analysis showed that more pre-existent MAs disappeared than new MAs developed, and the absolute number of MAs also decreased.

Identifiable Peripheral Retinal Lesions Using Ultra-Widefield Scanning Laser Ophthalmoscope and Its Usefulness in Myopic Patients

Purpose: To investigate identifiable peripheral retinal lesions in patients with myopia or high myopia and to evaluate the usefulness of ultra-widefield scanning laser ophthalmoscope in retina clinic settings. Methods: We evaluated fundus images of 149 patients acquired using an ultra-widefield scanning laser ophthalmoscope. Manual fundus examination by a retinal specialist was performed and sensitivity and specificity were calculated by comparing the findings of the two different fundus examination methods. Results: Variable peripheral retinal lesions were observed: lattice degeneration (24.1% in myopia, 36.6% in high myopia), white without pressure (17.7% in myopia, 20.7% in high myopia), retinal break (5.1% in myopia, 7.5% in high myopia) and retinal detachment (1.3% in myopia, 4.2% in high myopia). The incidence of lattice degeneration was significantly higher in myopic eyes than in highly myopic eyes (p = 0.043). The examination sensitivities were as follows: lattice degeneration (84.2% in myopia, 91.0% in high myopia), white without pressure (100.0% in both myopia and high myopia), retinal break (75.0% in myopia, 43.8% in high myopia) and retinal detachment (100.0% in myopia, 66.7% in high myopia). The examination specificities were 100.0% in all cases. Conclusions: Diagnostic sensitivities of ultra-widefield scanning laser ophthalmoscope were 90.8% in patients with myopia, 91.0% in patients with high myopia and 90.9% in totally myopic patients, which were relatively high values. Therefore, the ultra-widefield scanning laser ophthalmoscope is useful as auxiliary equipment for myopic patients in retina clinic settings. J Korean Ophthalmol Soc 2014;55(12):1814-1820

Prevalence of choroidal naevi using scanning laser ophthalmoscope

To determine the prevalence of choroidal naevi in a healthy population using an ultra-wide scanning laser ophthalmoscope which can capture up to a 200° field of view of the retina, without pupil dilation. Subjects were recruited from a college population. Each subject underwent an eye examination that included retinal and choroidal imaging using the Optos scanning laser ophthalmoscope and completed a self-administered questionnaire. Univariate and multivariate regression analysis were performed to identify associated factors with choroidal naevi. The Optomap images of 406 participants (mean age 23.5 ± 4.4) were analysed. Thirty-nine subjects (10%) presented with at least one naevus in one eye, and multiple naevi were observed unilaterally in eight subjects. Drusen were noted in only one eye. The mean naevus diameter was 2.38 mm (± 2.07). Prevalence was not associated with either eye colour, time spent outdoors, visual impairment, or ethnic group, but was significantly associated with male gender (OR 2.41, p = 0.009), blond/red hair colour (OR 2.42, p = 0.037), skin that neither burns nor tans (OR 2.8, p = 0.02) and habitual sunglasses use (OR 0.33, p = 0.002). A higher prevalence of choroidal naevi was detected in this college population compared to other population-based studies. This is likely due to the use of an ultra-wide field scanning laser ophthalmoscope which provides up to 200° of the fundus. The naevi were associated with several factors.

Non-contact ultra-widefield imaging of retinopathy of prematurity using the Optos dual wavelength scanning laser ophthalmoscope

The purpose of this report is to demonstrate that a non-contact ultra-widefield dual wavelength laser camera (Optos) is able to capture high-quality images in retinopathy of prematurity (ROP). We conducted a retrospective review of patients attending the Oxford Eye Hospital with ROP between 1 August 2012 and 16 November 2012 that underwent standard clinical assessment. Anterior segment imaging, where relevant, was performed with Retcam. Retinal imaging was then performed with Optos, using a modified 'flying baby position'. The Optos scanning laser ophthalmoscope was able to acquire ultra-widefield fundal images in nine ROP subjects. The images obtained show clear views of the different stages of ROP features at the posterior pole and peripheral retina. Regression of ROP features were identified, following laser and intravitreal bevacizumab treatment. Additionally, 'skip areas' missed by initial laser treatment could be identified in the peripheral retina. The Optos ultra-widefield scanning laser ophthalmoscope is capable of acquiring clinically useful high-quality images of the fundus in ROP subjects. The imaging technique could potentially be used in monitoring ROP progression and documenting ROP regression following treatment.

Comparison of image-assisted versus traditional fundus examination.

The purpose of this study was to evaluate the ability of image-assisted fundus examination to detect retinal lesions compared with traditional fundus examination. Subjects were imaged using a nonmydriatic ultrawide field scanning laser ophthalmoscope. After imaging, subjects underwent both a traditional and an image-assisted fundus examination, in random order. During the image-assisted method, ultrawide field scanning laser ophthalmoscopic images were reviewed in conjunction with a dilated fundus examination. Lesions detected by each method were assigned to one of three regions, ie, optic disc, posterior pole/macula, or mid-to-peripheral retina. Discrepancies between the image-assisted and the traditional examination methods were adjudicated by a retinal ophthalmologist. In total, 170 subjects (339 eyes) were recruited. Agreement between image-assisted and traditional fundus examination varied by lesion type and was excellent for staphyloma (kappa 0.76), fair for suspicious cupping (kappa 0.66), drusen in the posterior pole/macula and mid-to-peripheral retina (0.45, 0.41), retinal pigment epithelial changes in the posterior pole/macula (0.54), peripheral retinal degeneration (0.50), cobblestone (0.69), vitreoretinal interface abnormalities (0.40), and vitreous lesions (0.53). Agreement was poor for hemorrhage in the mid-to-peripheral retina (kappa 0.33), and nevi in the mid-to-peripheral retina (0.34). When the methods disagreed, the results indicated a statistically significant advantage for the image-assisted examination in detecting suspicious cupping (P = 0.04), drusen in the posterior pole/macula and mid-to-peripheral retina (P = 0.004, P < 0.001), retinal pigment epithelial changes in the posterior pole/macula (P = 0.04), nevi in the posterior pole/macula and mid-to-peripheral retina (P = 0.01, P = 0.007), peripheral retinal degeneration (P < 0.001), hemorrhage in the mid-to-peripheral retina (P = 0.01), and vitreous lesions (P < 0.001). Image-assisted fundus examination may enhance detection of retinal lesions compared with traditional fundus examination alone.

Assessment of Diabetic Retinopathy Using Nonmydriatic Ultra-Widefield Scanning Laser Ophthalmoscopy (Optomap) Compared With ETDRS 7-Field Stereo Photography

OBJECTIVETo compare the diagnostic properties of a nonmydriatic 200° ultra-widefield scanning laser ophthalmoscope (SLO) versus mydriatic Early Treatment of Diabetic Retinopathy Study (ETDRS) 7-field photography for diabetic retinopathy (DR) screening.RESEARCH DESIGN AND METHODSA consecutive series of 212 eyes of 141 patients with different levels of DR were examined. Grading of DR and clinically significant macular edema (CSME) from mydriatic ETDRS 7-field stereo photography was compared with grading obtained by Optomap Panoramic 200 SLO images. All SLO scans were performed through an undilated pupil, and no additional clinical information was used for evaluation of all images by the two independent, masked, expert graders.RESULTSTwenty-two eyes from ETDRS 7-field photography and 12 eyes from Optomap were not gradable by at least one grader because of poor image quality. A total of 144 eyes were analyzed regarding DR level and 155 eyes regarding CSME. For ETDRS 7-field photography, 22 eyes (18 for grader 2) had no or mild DR (ETDRS levels ≤ 20) and 117 eyes (111 for grader 2) had no CSME. A highly substantial agreement between both Optomap DR and CSME grading and ETDRS 7-field photography existed with κ = 0.79 for DR and 0.73 for CSME for grader 1, and κ = 0.77 (DR) and 0.77 (CSME) for grader 2.CONCLUSIONSDetermination of CSME and grading of DR level from Optomap Panoramic 200 nonmydriatic images show a positive correlation with mydriatic ETDRS 7-field stereo photography. Both techniques are of sufficient quality to assess DR and CSME. Optomap Panoramic 200 images cover a larger retinal area and therefore may offer additional diagnostic properties.

Wide-field Retinal Imaging in the Management of Noninfectious Posterior Uveitis

To determine whether the use of ultra wide-field imaging changes the management or determination of disease activity in patients with noninfectious posterior uveitis. Prospective, observational case series. setting: Divisions of Retina and Ocular Immunology at single academic medical center. patient population: Total of 43 patients with noninfectious posterior uveitis seen by 4 investigators at the Wilmer Eye Institute. procedures: Each patient underwent standard clinical examination, followed by ultra wide-field scanning laser ophthalmoscope (SLO) imaging and angiography. Investigators successively determined disease activity and management decisions based on clinical examination, examination plus simulated 30- or 60-degree fluorescein angiography (FA) (obtained by physically narrowing the field of view of the wide-field images), examination plus ultra wide-field SLO images, and examination plus wide-field FA. main outcome measures: The primary outcome was the percentage of patients whose management changed based on the availability of wide-field imaging, compared with standard examination and imaging. The secondary outcome was detection of disease activity with and without wide-angle imaging. Management was altered in 7 of 43 patients (16%) based on examination and limited FA, whereas 21 of 43 patients (48%) had management change with the use of the ultra wide-field imaging and angiography (P < .001). Disease activity was detected in 22 of 43 patients (51%) based on examination and simulated conventional imaging, and in 27 of 43 (63%) with wide-field imaging (P = .27). The index study, with several design limitations, has suggested that ultra wide-field imaging may alter management decisions compared to standard-of-care imaging and clinical examination. Additional studies, including longitudinal evaluations, are needed to determine whether these findings, or the subsequent management alterations, may improve patient outcomes.

Diabetische Retinopathie

The aim of the study was to compare the diagnostic properties of a non-mydriatic 200° ultra-widefield scanning laser ophthalmoscope (SLO) with mydriatic ETDRS 7-field fundus photography for diabetic retinopathy screening. A consecutive series of 66 eyes from 34 patients with different levels of diabetic retinopathy (DR) were examined. Grading of DR and macular edema (ME) obtained from mydriatic ETDRS 7-field fundus photography were compared with grading obtained from Optomap Panoramic 200MA SLO images. All SLOs were performed with an undilated pupil and no additional clinical information was used for evaluation of images by two independent, masked experts. A total of 14 eyes from ETDRS 7-field fundus photography and 11 eyes from Optomap could not be graded by at least one grader due to poor image quality, yielding 48 eyes for comparison purposes. Of the 48 ETDRS 7-field fundus photographs, 9 (11 for grader 2) eyes had no or mild DR (ETDRS levels ≤20) and 17 (23 for grader 2) eyes had no ME. Agreement of Optomap retinopathy grading with ETDRS 7-field fundus photography was good, kappa 0.70 for grader 1 and kappa 0.66 for grader 2. There was good agreement between both techniques for ME, grader 1 kappa 0.68 and grader 2 kappa 0.74. Grading of DR levels from Optomap Panoramic 200MA non-mydriatic images showed a good correlation with mydriatic ETDRS 7-field fundus photography. Both techniques are of sufficient quality for a valid assessment of DR. Optomap Panoramic 200MA images cover a larger retinal area and might therefore offer additional diagnostic properties.

Nonmydriatic screening for diabetic retinopathy by ultra-widefield scanning laser ophthalmoscopy (Optomap)

To compare the diagnostic properties of a nonmydriatic 200 degrees ultra-widefield scanning laser ophthalmoscope (SLO) versus onsite mydriatic ophthalmologic examination for diabetic retinopathy. A consecutive series of 51 eyes of 51 patients with different levels of diabetic retinopathy (DR) was examined. Grading of diabetic retinopathy and macular edema obtained on stereoscopic dilated funduscopy by a retina specialist was compared against grading obtained from Optomap Panoramic200 SLO images. All SLOs were performed with an undilated pupil, and no additional clinical information was used for evaluation of the Optomap images by three independent, masked expert graders. A total of five images (9.8%) were not gradable due to insufficient quality. Clinically 4 eyes had proliferative diabetic retinopathy (PDR), while 9 had none, 5 mild, 19 moderate and 14 severe nonproliferative diseases (NPDR). Of the gradable 46 images, a clinically significant macular edema (CSME) was present in 28 eyes clinically. On Optomap, all eyes with PDR were detected as being proliferative, and a sensitivity of 94% at a specificity of 100% was obtained for all graders to detect more than mild DR. Agreement between Optomap retinopathy grading and clinical assessment was good with unweighted kappas of 0.68, 0.68 and 0.51. Assessment of CSME yielded sensitivities of 93, 93 and 89% at specificities of 89, 72 and 83%. The Optomap Panoramic200 nonmydriatic images are of sufficient quality to assess DR and CSME validly and therefore fulfill the basic requirements for telescreening programs.

Peripheral retinal changes in acute retinal necrosis imaged by ultra widefield scanning laser ophthalmoscopy

Peripheral retinal changes in acute retinal necrosis imaged by ultra widefield scanning laser ophthalmoscopy