VISUALIZATION OF MACULAR PUCKER BY MULTICOLOR SCANNING LASER IMAGING

Multicolor imaging: Current clinical applications

Multicolor (MC) imaging is an innovative pseudocolor fundus imaging modality based on confocal scanning laser ophthalmoscopy. It effectively scans the retina at different depths to create a composite image. The green reflectance image depicts the middle retinal while blue reflectance image provides images of the retinal surface. The infrared reflectance image depicts retinal structures at the level of outer retina and choroid. We systematically analyze published case reports, case series, and original articles on MC imaging where it has helped in discovering additional clinical features of retinal diseases not readily apparent on conventional color fundus photography and played a role in monitoring the response to treatment.

Clinical application of multicolor scanning laser ophthalmology in diagnosis and grading of central retinal artery occlusion

Purpose

To characterize features of central retinal artery occlusion (CRAO) using multicolor (MC) imaging and to assess the differences in CRAO grading between color fundus photography (CFP) and MC image qualitatively and quantitatively.

Methods

We conducted a prospective, cross-sectional study in the Department of Ophthalmology of Renmin Hospital of Wuhan University. In total, 86 acute CRAO patients were included. Spectral-domain optical coherence tomography (SD-OCT), CFP, and MC examinations were taken at baseline. Based on the findings of these three examinations, CRAO was divided into three grades (incomplete, subtotal, and total). Based on OCT grading criteria, we qualitatively compared the ability of grading CRAO by CFP and MC. CRAO patient's visual acuity (VA) was obtained from the initial visit. The retinal thickness was measured by SD-OCT. Superficial capillary plexus (SCP) and deep capillary plexus (DCP) were obtained from optical coherence tomography angiography (OCTA) examinations. Quantitative data were compared across the three acute CRAO subgroups and against three examination findings.

Results

MC image had significantly higher power of acute CRAO detection than CFP (P = 0.03). In the same group of CRAO patients, there was no significant difference in VA when comparing OCT with the MC grading system or with the CFP grading system (all P > 0.05). Significant differences in VA were found between the three CRAO subgroups only under MC grading (P = 0.016). In incomplete CRAO patients, significant differences were found in central fovea thickness (CFT) when comparing OCT with the CFP grading system (P = 0.019). In the same group of CRAO patients, there was no significant difference in retinal thickness when comparing OCT with the MC grading system (All P > 0.05). Significance differences in CFT (P < 0.001), innermost retinal layer (IMRL; P < 0.01), middle retinal layer (MRL; P < 0.001), and outer retinal layer (ORL; P = 0.021) were found between the three CRAO subgroups by MC grading. Vessel density of SCP showed a statistically increased as the severity of three CRAO subgroups (P = 0.03), whereas DCP did not have significant differences (P = 0.745). Comparisons were made between the OCT grading method and the MC and CFP grading methods; there is no significant difference in vessel density of SCP and DCP (All P > 0.05).

Conclusion

The images obtained by MC are superior to those obtained by CFP in CRAO grading, retinal thickness, and vessel density measurement. MC imaging may be more capable of CRAO grading than OCT. We recommend MC imaging to determine CRAO severity to guide disease treatment and predict visual prognosis.

Ultra-wide field and new wide field composite retinal image registration with AI-enabled pipeline and 3D distortion correction algorithm

PURPOSE

This study aimed to compare a new Artificial Intelligence (AI) method to conventional mathematical warping in accurately overlaying peripheral retinal vessels from two different imaging devices: confocal scanning laser ophthalmoscope (cSLO) wide-field images and SLO ultra-wide field images.

METHODS

Images were captured using the Heidelberg Spectralis 55-degree field-of-view and Optos ultra-wide field. The conventional mathematical warping was performed using Random Sample Consensus-Sample and Consensus sets (RANSAC-SC). This was compared to an AI alignment algorithm based on a one-way forward registration procedure consisting of full Convolutional Neural Networks (CNNs) with Outlier Rejection (OR CNN), as well as an iterative 3D camera pose optimization process (OR CNN + Distortion Correction [DC]). Images were provided in a checkerboard pattern, and peripheral vessels were graded in four quadrants based on alignment to the adjacent box.

RESULTS

A total of 660 boxes were analysed from 55 eyes. Dice scores were compared between the three methods (RANSAC-SC/OR CNN/OR CNN + DC): 0.3341/0.4665/4784 for fold 1-2 and 0.3315/0.4494/4596 for fold 2-1 in composite images. The images composed using the OR CNN + DC have a median rating of 4 (out of 5) versus 2 using RANSAC-SC. The odds of getting a higher grading level are 4.8 times higher using our OR CNN + DC than RANSAC-SC (p < 0.0001).

CONCLUSION

Peripheral retinal vessel alignment performed better using our AI algorithm than RANSAC-SC. This may help improve co-localizing retinal anatomy and pathology with our algorithm.

Relevance of multicolor imaging, its component channels, and fundus autofluorescence in describing macular telangiectasia type-2 (MacTel) lesion characteristics

PURPOSE

The aim of the study was to describe imaging characteristics and detection rates of phenotypic features in macular telangiectasia type-2 (MacTel) on multicolor (MC), blue reflectance (BR), green reflectance (GR), infrared reflectance (IR), and fundus autofluorescence (FAF) and to evaluate sensitivity, specificity, and predictive values across modalities.

METHODS

In this monocentric observational study, 282 eyes of 148 patients with MacTel underwent color fundus photograph, MC, BR, GR, IR, FAF, spectral-domain optical coherence tomography (SD-OCT), OCT-angiography (OCT-A), and fundus fluorescein angiography (FFA). Grading was done by two graders qualitatively and quantitatively for the presence of the following prespecified MacTel findings [crystals, right-angle vessels (RAVs), plaques, subretinal neovascularization (SRNV), and MacTel area]. Across each imaging modality, the detection rate of RAVs and SRNV was compared with reference standard OCT-A (RAVs and SRNV) and FFA (SRNV), whereas that of plaques was compared with reference standard SD-OCT.

RESULTS

MC identified overall MacTel characteristics in 92.7% of eyes. Regarding the presence, number, and quadrants of RAVs and the presence and number of crystals, MC and GR had superior detection rates as well as the highest sensitivity and negative predictive value. Retinal plaques were better detected using FAF (97%), followed by MC (88%). In proliferative MacTel, SRNV was identified in 86% and 79% of eyes on MC and IR, respectively. While BR clearly delineated MacTel area in 100% eyes, FAF was able to ascertain a larger area of involvement in proliferative MacTel.

CONCLUSION

The findings demonstrate the ability of MC, its component channels, and FAF to describe MacTel characteristics qualitatively and quantitatively.

Review of Retinal Imaging Modalities for Hydroxychloroquine Retinopathy

This review provides an overview of conventional and novel retinal imaging modalities for hydroxychloroquine (HCQ) retinopathy. HCQ retinopathy is a form of toxic retinopathy resulting from HCQ use for a variety of autoimmune diseases, such as rheumatoid arthritis and systemic lupus erythematosus. Each imaging modality detects a different aspect of HCQ retinopathy and shows a unique complement of structural changes. Conventionally, spectral-domain optical coherence tomography (SD-OCT), which shows loss or attenuation of the outer retina and/or retinal pigment epithelium-Bruch's membrane complex, and fundus autofluorescence (FAF), which shows parafoveal or pericentral abnormalities, are used to assess HCQ retinopathy. Additionally, several variations of OCT (retinal and choroidal thickness measurements, choroidal vascularity index, widefield OCT, en face imaging, minimum intensity analysis, and artificial intelligence techniques) and FAF techniques (quantitative FAF, near-infrared FAF, fluorescence lifetime imaging ophthalmoscopy, and widefield FAF) have been applied to assess HCQ retinopathy. Other novel retinal imaging techniques that are being studied for early detection of HCQ retinopathy include OCT angiography, multicolour imaging, adaptive optics, and retromode imaging, although further testing is required for validation.

Quantitative approaches in multimodal fundus imaging: State of the art and future perspectives

When it first appeared, multimodal fundus imaging revolutionized the diagnostic workup and provided extremely useful new insights into the pathogenesis of fundus diseases. The recent addition of quantitative approaches has further expanded the amount of information that can be obtained. In spite of the growing interest in advanced quantitative metrics, the scientific community has not reached a stable consensus on repeatable, standardized quantitative techniques to process and analyze the images. Furthermore, imaging artifacts may considerably affect the processing and interpretation of quantitative data, potentially affecting their reliability. The aim of this survey is to provide a comprehensive summary of the main multimodal imaging techniques, covering their limitations as well as their strengths. We also offer a thorough analysis of current quantitative imaging metrics, looking into their technical features, limitations, and interpretation. In addition, we describe the main imaging artifacts and their potential impact on imaging quality and reliability. The prospect of increasing reliance on artificial intelligence-based analyses suggests there is a need to develop more sophisticated quantitative metrics and to improve imaging technologies, incorporating clear, standardized, post-processing procedures. These measures are becoming urgent if these analyses are to cross the threshold from a research context to real-life clinical practice.

The role of near-infrared reflectance imaging in retinal disease: A systematic review

Near-infrared reflectance (NIR) retinal imaging aids in a better visualization of structures at the level of outer retina, retinal pigment epithelium, and choroid. It has multiple advantages, including easy acquisition in association with structural spectral domain optical coherence tomography, more comfort for patients, and enhanced contrast and spatial resolution. It helps in the diagnosis of chorioretinal diseases that present with minimal funduscopic findings and can be used to follow up many chorioretinal conditions. We describe the chorioretinal NIR imaging appearance and the clinical role of NIR imaging in ocular inflammatory disease, vascular and acquired disease, degenerative disease, tumors, associated systemic condition, toxic and traumatic disease, optic nerve head conditions, and physiological findings.

Comparison of Multicolor Scanning Laser Imaging and Color Fundus Photography in Evaluating Vessel Whitening in Branch Retinal Vein Occlusion

INTRODUCTION

Few studies have explored MultiColor™ imaging (MCI) in evaluating retinal vascular diseases, particularly branch retinal vein occlusion (BRVO). This study aimed to compare the identification of retinal vessel whitening in BRVO using MCI by scanning confocal laser versus conventional white-flash color fundus photography (CFP).

METHODS

Paired images of consecutive patients diagnosed with BRVO who underwent same-day MCI and CFP were reviewed. Visualization of vessel whitening on MCI and CFP was graded and scored using a scale by two masked graders. A longitudinal analysis of the vessel grading score was performed to evaluate the vessel whitening detection by MCI. A correlation analysis was conducted between vessel whitening on MCI and the measured area of retinal ischemia on fluorescein angiography to evaluate the MCI performance.

RESULTS

Forty-four eyes of 41 patients (mean age 69 ± 14 years; 61% female) were analyzed. MCI demonstrated superior vessel whitening visibility score than CFP (p < 0.001). Longitudinal analysis showed no significant changes in vessel whitening visibility scores over a mean follow-up time of 430 ± 648 days (p = 0.655). There was a significantly positive correlation between the grading score of vessels whitening by MCI and the area of ischemia by fluorescein angiography (r2 = 0.15; p = 0.036).

CONCLUSION

MCI appears to provide a superior detection of whitening BRVO compared to CFP, serving as a rapid and non-invasive correlate of retinal ischemia.

Choroidal Melanocytic Hamartoma

We report on a case series that revealed flat, choroidal lesions on optical coherence tomography (OCT) and on enface MultiColor® (MCI) imaging of the fundus but were not noticeable on clinical examination or conventional color fundus images. This observational study included 12 eyes from 11 patients who had distinct, orange-colored lesions on MCI. Retinal imaging was conducted using conventional color fundus photography and OCT. On the color fundus images and the blue and green reflectance channels of MCI, each of the lesions was difficult to distinguish. On the infrared channel, the lesion was identified as bright white in color and bright orange on the multicolor image. The lesion was identified on OCT as a flat, homogeneous hyperreflective lesion involving the choroid, with an intact overlying retinal pigment epithelium and retinal layers. A comparison of the clinical and imaging features with other known entities led to the conclusion that the lesion was a distinct clinical entity. The presence of melanin in the lesion was confirmed based on the retinal imaging findings and the light absorption properties of melanin. As a result, the lesion was named as 'choroidal melanocytic hamartoma'. A longer follow-up is required to confirm the benign nature of this clinical entity.

Progress of Imaging in Diabetic Retinopathy-From the Past to the Present

Advancement of imaging technology in retinal diseases provides us more precise understanding and new insights into the diseases' pathologies. Diabetic retinopathy (DR) is one of the leading causes of sight-threatening retinal diseases worldwide. Colour fundus photography and fluorescein angiography have long been golden standard methods in detecting retinal vascular pathology in this disease. One of the major advancements is macular observation given by optical coherence tomography (OCT). OCT dramatically improves the diagnostic quality in macular edema in DR. The technology of OCT is also applied to angiography (OCT angiograph: OCTA), which enables retinal vascular imaging without venous dye injection. Similar to OCTA, in terms of their low invasiveness, single blue color SLO image could be an alternative method in detecting non-perfused areas. Conventional optical photography has been gradually replaced to scanning laser ophthalmoscopy (SLO), which also make it possible to produce spectacular ultra-widefield (UWF) images. Since retinal vascular changes of DR are found in the whole retina up to periphery, it would be one of the best targets in UWF imaging. Additionally, evolvement of artificial intelligence (AI) has been applied to automated diagnosis of DR, and AI-based DR management is one of the major topics in this field. This review is trying to look back on the progress of imaging of DR comprehensively from the past to the present.

Design Study of a Large-Angle Optical Scanning System for MEMS LIDAR

MEMS-based LIDAR has the advantages of fast-scanning, simple structure, small volume, and light weight, which make it a hot topic for 3D imaging. In order to overcome the limited scanning angle of the current MEMS mirrors, a large angle MEMS-based optical scanning system was designed using telephoto structure. In this design an f-θ lens group is used for flat field scanning and a symmetrical cemented lens group is used for angle expansion. The principle of this system is discussed in detail and an optical design is implemented by ZEMAX software. The designed system realized a scanning angle as large as 57° and is in excellent linear relation with the tilt angle of the MEMS mirror. At the target distance of 100 m, the maximum RMS radius of the light spot is only 7 cm. This optical scanning system shows a significant application potentiality for 3D imaging LIDAR.

Sensitivity and specificity of MultiColor imaging in detecting proliferative diabetic retinopathy

PURPOSE

To evaluate the accuracy of MultiColor imaging (MC) compared to fluorescein angiography (FA) in detecting proliferative diabetic retinopathy (PDR) and associated diabetic retinopathy features.

METHODS

Fifty-nine eyes from 38 PDR patients were included. MC images were reviewed by 2 independent masked graders. A qualitative analysis based on the following features was performed: neovascular complexes (NVC), disc neovascularization (NVD), neovascularization elsewhere (NVE), microaneurysm (MA), intraretinal hemorrhage (IRH), vitreous hemorrhage (VH), preretinal hemorrhage (PRH), fibrosis, hard exudates (HE), epiretinal membrane (ERM), diabetic macular edema (DME), ischemia and laser spots (LS). Measures of diagnostic accuracy compared to FA were determined.

RESULTS

The sensitivity for the detection of NVC using MC was 95.1%, with a specificity of 40.0%, positive predictive value (PPV) of 92.9% and negative predictive value (NPV) of 50.0%. Sensitivity and specificity were higher in detecting NVD (88.9% and 76.9%) while NVE registered higher PPV (88.9%). MC was highly sensitive in detecting IRH, HE, ERM and LS (100%), MA (98.0%) and fibrosis (95.5%). Highest specificity was found for VH (100.0%), DME (100.0%), PRH (98.1%) and LS (89.5%). The area under the receiver-operating characteristic analysis of MC was excellent in NVD (0.83, 95% confidence interval (CI), 0.71-0.95, p < 0.001), IRH (0.89, 95% CI 0.74-1.00, p < 0.001), VH (0.81, 95% CI 0.60-1.00, p = 0.005) and PRH (0.89, 95% CI 0.68-1.00, p = 0.004) and outstanding in LS detection (0.95, 95% CI 0.87-1.00, p < 0.001). These results are likely due to the contrast and quality of the MC since better discrimination is enabled by the green wavelength.

CONCLUSION

MC is useful in evaluation of PDR patients and can complement noninvasive imaging. MC detected some PDR features more accurately than FA such as NVD, IRH, VH, PRH, and LS.

MORE EFFECTIVE SCREENING FOR EPIRETINAL MEMBRANES WITH MULTICOLOR SCANNING LASER OPHTHALMOSCOPE THAN WITH COLOR FUNDUS PHOTOGRAPHS

PURPOSE

To assess the ability of the multicolor scanning laser ophthalmoscope (MC-SLO) to screen for epiretinal membranes (ERMs).

METHODS

A retrospective cross-sectional study of 35 eyes of 32 patients with an ERM detected by optical coherence tomography and 46 eyes of 23 healthy volunteers. The detection of the ERM was graded into three visibility scores-1, not visible, 2, barely visible, and 3, clearly visible-by retina specialists or by ophthalmology residents. The sensitivity and specificity of the detection with the merged image of the MC-SLO or color fundus photographs (CFPs) were calculated.

RESULTS

The sensitivity for ERM detection in the MC-SLO and CFP were 91.4% and 65.7% by specialists and 97.1% and 60.0% by residents. The specificity for both devices was 100% by specialists and residents. The visibility score for the MC-SLO images were significantly higher than that for the CFP by both specialists and residents. In addition, the visibility score for the MC-SLO determined by residents was significantly higher than that for the CFP by specialists.

CONCLUSION

The detection of an ERM is better with the MC-SLO images than with CFP. Furthermore, the ERM detection in the MC-SLO images by residents was comparable to that by specialists.

CLINICAL APPLICATION OF MULTICOLOR IMAGING IN CENTRAL SEROUS CHORIORETINOPATHY

PURPOSE

To characterize features of central serous chorioretinopathy (CSC) using multicolor (MC) imaging and to compare the efficacy of using MC imaging and traditional color fundus photography (CFP) for detecting features of CSC.

METHODS

A retrospective review of 75 eyes of 69 participants with CSC from the Eye Center of the Renmin Hospital of Wuhan University. The patients underwent same-day CFP, fundus fluorescein angiography (FFA), spectral domain optical coherence tomography (SD-OCT), and MC imaging (including infrared reflectance (IR), green reflectance (GR), blue reflectance (BR), combined standard MC image, and green-blue-enhanced image). Positive CSC lesions were evaluated using FFA and SD-OCT. Features in images of CFP, standard MC, green-blue-enhanced, IR, GR, and BR were analyzed and calculated.

RESULTS

Among the 75 eyes of 69 patients, 75 eyes with subretinal fluid (SRF) and retinal pigment epithelial (RPE) leakage point, and 43 eyes with RPE damage were observed by FFA and SD-OCT. The detection rate of SRF was significantly higher with the standard MC image (92.0%), green-blue-enhanced image (92.0%), IR (88.0%), and GR (88.0%) than that with CFP (66.7%) (P < 0.05). Blue reflectance (45.3%) was associated with lower rate of SRF detection compared to CFP (P < 0.05). The standard MC image (84.0%), green-blue-enhanced image (84.0%), IR (78.7%), and GR (80%) delineated the boundaries of SRF more effectively than CFP (44%). The abnormal areas corresponding to RPE leakage points on FFA were observed with the standard MC image, green-blue-enhanced image, and IR at detection rates of 90.7, 82.7, and 90.7%, respectively, which were significantly higher than with CFP (29.3%) (P < 0.05). However, the detection rates of the abnormalities corresponding to leakage on FFA were lower with GR (5.3%) and BR (1.3%) than those with CFP (P < 0.05). Areas of RPE damage on FFA were observed at the same locations with the standard MC image, green-blue-enhanced image, and IR at detection rates of 97.7, 93.0, and 95.3%, respectively, which were significantly higher than with CFP (41.9%) (P < 0.05). Compared with CFP, the detectable rates of RPE damage on GR (14.0%) and BR (9.3%) were lower (P < 0.05).

CONCLUSION

As an adjunct to SD-OCT, the MC image can delineate the extent or boundaries of SRF more effectively than CFP. As an adjunct to FFA, the MC image can identify foci of leakage more effectively than CFP. The MC image, particularly the IR channel, can identify areas of RPE damage more effectively than CFP. Therefore, the MC image may be a useful adjunct to FFA and OCT for detecting or monitoring CSC.

Preoperative imaging optimized for epiretinal membrane surgery

Background

To compare imaging modalities for visualizing primary epiretinal membrane (ERM) with each other and with intraoperative digital images (IDI) after blue staining.

Methods

The records of consecutive patients operated for primary ERM over a 12-month period were retrospectively reviewed. Preoperative imaging included color fundus photography (CFP), En Face spectral-domain optical coherence tomography (OCT), 45° infrared- (IR) and blue-reflectance (BR) scanning laser ophthalmoscopy. All images were qualitatively analyzed and scored from 0–4 according to the ability to visualize ERM details (0 = no visible ERM or vessel contraction, 1 = vessel contraction, 2 = retinal folds, 3 = ERM limits, 4 = elevated ERM edge). The preoperative ERM morphology was then compared to that seen on the IDI acquired after 1-min blue dye staining when available.

Results

Seventy eyes were included. The highest score for ERM visualization was obtained on BR and En Face OCT. A score of 3 or 4 was obtained in 68.5%, 62.1%, 17.9% and 13.6% of cases on En Face OCT, BR, CFP and IR images, respectively. IDI were available for 20 eyes, and showed a similar ERM morphology compared to preoperative images in most cases: a negative staining pattern corresponded to a plaque on En face OCT in 91% of eyes. However, IDI failed to show the ERM edges in 37.5% of cases.

Conclusion

ERM morphology was better visualized preoperatively by BR and En Face OCT, in a similar way to the IDI after staining. Future intraoperative visualization systems could integrate both imaging modalities overlaid with the IDI for guiding ERM removal instead of staining.

Use of the new MultiColour SPECTRALIS® software for identifying retinal nerve fibre layer defects

The classical fibre photography traditionally used to identify defects in the retinal nerve fibre layer (RNFL), has been partially discontinued due to poor availability. The new MultiColour module of SPECTRALIS® Optical Coherence Tomography (OCT), using three different laser wavelengths simultaneously, can provide images that identify the structures of the retina in different colours according to their depth. A small concordance study was conducted to determine the usefulness of the new MultiColour software versus traditional fibre photography in identifying RNFL defects. The inter-observer agreement in the interpretation of MultiColour images was good (κ=.746; P<.001), as by using Multicolour they were able to identify around 70% of patients with mild glaucoma. It is believed that the new Multicolour software is useful in evaluating RNFL defects, and is easy to perform.

Multimodal Imaging of Lamellar Macular Holes

Evolution of imaging techniques has renewed interest in the diagnosis of lamellar macular hole (LMH) and greatly implemented the possibilities of gaining more detailed insights into its pathogenesis. Among noninvasive techniques, optical coherence tomography (OCT) is considered the primary examination modality to study LMHs, given its ability to image foveal structure and its widespread availability. OCT also allows to resolve the epiretinal materials associated with LMH, i.e., tractional epiretinal membranes (ERMs) and epiretinal proliferation (EP). En face OCT reconstructions are useful to confirm the foveal abnormalities shown by the eyes with LMH, whereas OCT angiography may reveal alterations of the size and shape of the foveal avascular zone and alterations of the density of the superficial and deep vascular plexuses. On slit-lamp biomicroscopy or fundus camera examination, LMH appears as a round or oval, reddish lesion at the center of the macula, slightly darker than the surrounding retina. The associated tractional ERM, causing wrinkling and glistening of the retinal surface, is usually readily appreciable, whereas EP is hardly apparent on biomicroscopy or fundus photography since the retina surface appears smooth. When imaged with blue fundus autofluorescence (B-FAF) imaging, LMHs are characterized by an increased autofluorescent signal, the intensity of which does not correlate with the thickness of the residual outer retinal tissue. Green reflectance and blue reflectance (BR) images clearly show the increased reflection and wrinkling of the retinal surface caused by tractional ERM associated with LMH. BR and multicolor imaging enable the visualization of EP associated with LMH in the form of a sharply demarcated dark area and in the form of a yellowish area surrounding the hole, respectively. Scarce data regarding invasive imaging techniques, such as fluorescein angiography, for the study of LMH are available in the literature. The aim of this review is to evaluate the contribution that each imaging modality can provide to study the morphologic characteristics of LMH.

Multicolor Scanning Laser Ophthalmoscopy Strengthens Surgeons' Preoperative Decision-Making and Intraoperative Performance on Epiretinal Membrane

Purpose

To determine whether multicolor scanning laser ophthalmoscopy (MC-SLO) was better than color fundus photography (CFP) to enhance residents and specialists’ preoperative decision-making and intraoperative performance on the epiretinal membrane (ERM).

Methods

Consecutive patients with idiopathic ERM were recruited prospectively. All the patients underwent MC-SLO and CFP imagings and were randomized into MC-SLO (n = 20) and CFP (n = 20) groups. Preoperatively, residents and specialists were required to have ERM delineation and select an optimal location for initial ERM peeling independently, based on the MC-SLO (MC-SLO group) or CFP (CFP group) images. Intraoperative optical coherence tomography (iOCT) was introduced to evaluate the accuracy.

Results

Preoperatively, residents and specialists acted more effectively in ERM delineation and selection of initial grasping location in the MC-SLO group (both P < 0.001). In the MC-SLO group, higher resident–specialist agreements were achieved in ERM delineation (P = 0.002) and selection of initial grasping location (P = 0.035). The iOCT revealed greater interobserver (iOCT–resident and iOCT–specialist) agreements of ERM delineation in MC-SLO group (P < 0.001 and = 0.027, respectively). Surgeons acted more effectively on completely peeling the ERM in the MC-SLO group (P < 0.001).

Conclusions

MC-SLO provided a better visual reference for residents and specialists in ERM delineation and the selection of an initial grasping location for the surgery, compared with CFP.

Translational Relevance

MC-SLO is able to help surgeons achieve better intraoperative performance and shorten the learning process for residents.

COMPARISON OF RETINAL PATHOLOGY VISUALIZATION IN MULTISPECTRAL SCANNING LASER IMAGING

PURPOSE

To compare retinal pathology visualization in multispectral scanning laser ophthalmoscope imaging between the Spectralis and Optos devices.

METHODS

This retrospective cross-sectional study included 42 eyes from 30 patients with age-related macular degeneration (19 eyes), diabetic retinopathy (10 eyes), and epiretinal membrane (13 eyes). All patients underwent retinal imaging with a color fundus camera (broad-spectrum white light), the Spectralis HRA-2 system (3-color monochromatic lasers), and the Optos P200 system (2-color monochromatic lasers). The Optos image was cropped to a similar size as the Spectralis image. Seven masked graders marked retinal pathologies in each image within a 5 × 5 grid that included the macula.

RESULTS

The average area with detected retinal pathology in all eyes was larger in the Spectralis images compared with Optos images (32.4% larger, P < 0.0001), mainly because of better visualization of epiretinal membrane and retinal hemorrhage. The average detection rate of age-related macular degeneration and diabetic retinopathy pathologies was similar across the three modalities, whereas epiretinal membrane detection rate was significantly higher in the Spectralis images.

CONCLUSION

Spectralis tricolor multispectral scanning laser ophthalmoscope imaging had higher rate of pathology detection primarily because of better epiretinal membrane and retinal hemorrhage visualization compared with Optos bicolor multispectral scanning laser ophthalmoscope imaging.

Multicolor imaging in macular telangiectasia-a comparison with fundus autofluorescence

PURPOSE

To describe various clinical features of idiopathic juxtafoveal retinal telangiectasis group 2A or idiopathic macular telangiectasia type 2 (MacTel) on multicolor imaging (MCI) and compare imaging findings of MacTel on MCI with fundus autofluorescence (FAF).

METHODS

Patients with a clinical diagnosis of MacTel based on Gass and Blodi's classification were included. FAF and MCI images were graded qualitatively for stage of disease, margins of involvement, hyperautofluorescence on FAF (corresponding retinal atrophy on MCI), and detection of crystals. FAF and MCI were graded quantitatively for the area and number of quadrants involved, hypoautofluorescene on FAF (corresponding intraretinal pigment hyperplasia or retinal pigment epithelium [RPE] atrophy on MCI), and foci of right-angled venules.

RESULTS

Seventy-eight eyes of forty five patients were included with both imaging modalities showing no difference with respect to staging of non-proliferative MacTel. Retinal crystals were recognized on MCI but not on FAF. Neurosensory retinal atrophy and  subretinal neovascular membranes were detected using MCI with 92.3 and 83.3% sensitivity, respectively. Intraretinal pigmented hyperplasia was more accurately detected (70.1 vs 58.4%) compared with RPE atrophy on MCI. MCI showed larger area of involvement, higher number of quadrants involved (p < 0.001), and better delineation of margins (p = 0.002) compared with FAF. A higher mean number of vessel dipping foci was noted on MCI in comparison with FAF (3.34 vs 3.1).

CONCLUSION

Various parameters were more easily defined using MCI compared with FAF which qualifies MCI as an enface depth-resolved imaging adjunct to conventional multimodal imaging in MacTel. The ability to detect enface as well as cross-sectional imaging features makes MCI a valuable tool in MacTel.

IDENTIFICATION OF POSTERIOR SEGMENT PATHOLOGY WITH EN FACE RETINAL IMAGING USING MULTICOLOR CONFOCAL SCANNING LASER OPHTHALMOSCOPY

PURPOSE

To assess posterior segment findings on multicolor confocal scanning laser ophthalmoscopy by correlation with spectral domain optical coherence tomography (SD-OCT) and to quantify agreement between these imaging modalities.

METHODS

Retrospective review of 159 eyes of 96 consecutive patients who underwent concurrent imaging with multicolor confocal scanning laser ophthalmoscopy and SD-OCT. Positive percent agreement and negative percent agreement were calculated for each finding identified on infrared, green, blue, and multicolor reflectance images using SD-OCT as a comparator.

RESULTS

Infrared reflectance best detected outer retinal and choroidal findings such as choroidal lesions, retinal pigment epithelium atrophy, peripapillary atrophy, and drusen (positive percent agreement 100, 92, 92, and 67%, respectively). Inner retinal changes including epiretinal membrane, lamellar macular hole, and inner retinal alterations were best detected on blue reflectance (positive percent agreement 94, 50, and 100%, respectively). Composite multicolor reflectance most effectively detected conditions with retinal elevation, including pigment epithelial detachment, intraretinal fluid, and subretinal fluid (positive percent agreement 65, 49, and 54%, respectively). Multicolor confocal scanning laser ophthalmoscopy detected intraretinal and subretinal hemorrhages, which were not detected on SD-OCT (negative percent agreement 87 and 97%, respectively).

CONCLUSION

Multicolor confocal scanning laser ophthalmoscopy is capable of identifying posterior segment pathology at various anatomical depths and may be a useful adjunct to SD-OCT for detecting or monitoring certain retinal conditions.

Validation of multicolor imaging signatures of central serous chorioretinopathy lesions vis-a-vis conventional color fundus photographs

Purpose

The current study compares the ability of multicolor imaging (MCI) to detect the lesions of central serous chorioretinopathy against conventional color fundus photographs (CFP).

Methods

It was a retrospective, observational case series of 93 eyes of 58 patients of central serous chorioretinopathy who underwent MCI and CFP. MCI and spectral-domain optical coherence tomography (SD-OCT) were performed using Spectralis SD-OCT system (HRA + OCT). CFP was obtained using FF 450 Plus fundus camera (Carl Zeiss Meditec, Jena, Germany). SD-OCT was considered gold standard for subretinal fluid (SRF) and retinal pigment epithelium detachment (PED). CFP was considered confirmatory investigation for fibrin and blue autofluorescence image (BAF) was considered gold standard to detect retinal pigment epithelium (RPE) atrophy.

Results

CFP could detect SRF in 41 (44.1%) eyes. MCI detected SRF in 43 (46.2%) eyes. The sensitivity and specificity of MCI to detect SRF were 70.7% and 94.3%, respectively. PED was detected by CFP in 21 (22.6%) eyes and MCI in 27 (29%) eyes. The sensitivity and specificity of MCI to detect PED were 70% and 97.7% respectively. CFP could pick RPE atrophy in 52 (55.9%) eyes whereas MCI was picked it in 78 (83.9%) of eyes.

Conclusion

Both MCI and CFP were inferior to a gold standard in identifying the SRF, PED, and RPE atrophy. However, MCI was better than CFP in comparison with gold standard for these clinical findings in CSC. Thus, MCI seems to be a more valuable imaging tool compared to CFP.

REAL-COLOR VERSUS PSEUDO-COLOR IMAGING OF FIBROTIC SCARS IN EXUDATIVE AGE-RELATED MACULAR DEGENERATION

PURPOSE

To compare the morphological characteristics of subretinal fibrosis in late age-related macular degeneration using multicolor (MC) imaging, color fundus photography (CFP), and ultra-widefield CFP (UWFCFP).

METHODS

Thirty-two eyes of 31 patients diagnosed with subretinal fibrosis complicating exudative age-related macular degeneration were included. Included eyes were imaged by MC, CFP, and UWFCFP. The overall ability to visualize fibrosis, its margins, and dissimilarity with surrounding atrophy was graded using a score (0: not visible, 1: barely visible, 2: mostly visible, and 3: fully visible) by two readers. Area of fibrosis was calculated. Scaling, lesion colocalization on all three imaging techniques, and area measurements were performed using ImageJ.

RESULTS

Ninety-six images of 32 eyes were graded. The average area of fibrosis was 14.59 ± 8.94 mm for MC, 13.84 ± 8.56 mm for CFP, and 13.76 ± 8.79 mm for UWFCFP. Fibrosis was fully visible in 87.5% of cases using MC and 50% using CFP and UWFCFP. Fibrosis' margins were sharply defined in 40.6% of eyes with MC, 15.6% and 9.4% with CFP and UWFCFP, respectively. Multicolor imaging provided superior distinction between fibrosis and atrophy (100% for MC vs. 13.4% for CFP and 33.3% for UWFCFP). The inter- and intra-reader agreement was high for all measurements (P < 0.0001).

CONCLUSION

Multicolor technology allows for improved visualization and analysis of subretinal fibrosis when compared with CFP and UWFCFP, especially when surrounding atrophy is present.

Correlation of multicolor images and conventional color fundus photographs with foveal autofluorescence patterns in diabetic macular edema

Purpose:

The aim of this study is to assess the ability of multicolour imaging (MCI) to detect foveal cysts in diabetic macular edema (DME) and compare it with conventional color fundus photography (CFP) and foveal autofluorescence (FAF) pattern.

Methods:

It was a retrospective review of 112 eyes of 84 DME patients with central foveal thickness ≥250 μ who underwent MCI, CFP and shortwave autofluorescence imaging. MCI was performed with Sepctralis spectral domain optical coherence tomography (SDOCT) (Heidelberg Engineering, Germany).

Results:

97 (86.6%) eyes had cystoid increased autofluorescence (cystoid iFAF), 9 (8%) had spot iFAF and 6 (5.35%) had irregular decreased FAF (dFAF). Among eyes with cystoid iFAF, OCT detected DME cysts in 93 (95.6%) eyes, MCI in 75 (77.3%) and CFP in 5 (5.15%) eyes. In all these eyes, the location of cysts on OCT and MCI corresponded with the location of cystoid iFAF, whereas none of the eyes with cyst seen on CFP correlated with the location of cystoid iFAF.

Conclusion:

MCI was superior to CFP in detecting DME cysts at fovea. It also correlated with hyperautofluorescence pattern in these eyes. MCI may have a potential role in diabetic retinopathy screening by segregating eyes with DME which would require treatment. Our findings need to be further validated in a larger and prospective study design.

Multicolor imaging in central serous chorioretinopathy - a quantitative and qualitative comparison with fundus autofluorescence

Central serous chorioretinopathy (CSCR) is characterised by choroidal hyperpermeability which results in neurosensory detachments (NSD) along with numerous retinal pigment epithelium (RPE) alterations such as RPE atrophy. Fundus autofluorescence (FAF) demonstrates the functionality of the RPE while multicolor imaging(MCI), by means of its three incident wavelengths, provides insight into clinical changes at various levels of the retina and choroid in CSCR. This study compares various clinical findings in CSCR (NSD, subretinal deposits, RPE atrophy, pigment epithelial detachments (PED) and pachyvessels) on the above mentioned imaging modalities both qualitatively and quantitatively. MCI showed higher mean cumulative area of RPE atrophic patches (6.3 ± 6.02 vs 5.7 ± 5.7 mm2, p = 0.046), PED (1.3 ± 1.4 vs 1.1 ± 1.2 mm2, p = 0.068) and NSD (17.2 ± 11.4 vs 15.7 ± 10.7 mm2, p = 0.033). MCI demonstrated better defined lesions (NSD, PED, RPE atrophy) and more number of eyes with PED and pachyvessels in comparison to FAF.Both investigations had a 100% sensitivity in detecting NSD and 100% specificity for sub retinal deposits. This study demonstrates the ability of MCI to quantitatively and qualitatively define various clinical features in CSCR and the advantages it holds over FAF. MCI can hence be considered as a useful imaging modality in documenting and monitoring various structural changes in eyes with CSCR.

Multicolor Imaging Characteristics of Best's Vitelliform Macular Dystrophy

A 40-year-old woman presented with vitellieruptive stage of Best's vitelliform macular dystrophy (BVMD) in the right eye and pseudohypopyon stage in the left eye. She underwent comprehensive ophthalmic examination and fundus imaging using multicolor (MC) imaging technology of Spectralis (Heidelberg Engineering, Heidelberg, Germany) spectral-domain-optical coherence tomography system. Composite MC imaging revealed larger area of retinal pigment epithelium atrophy in vitellierruptive stage of the disease in the right eye compared to color fundus photograph. Retinal elevation in the pseudohypopyon stage was better delineated on composite MC and blue reflectance images in the left eye. Subretinal lipofuscin was best seen in green reflectance and short-wave autofluorescence images. The present case reports the MC imaging features of BVMD.

[Possibilities of multicolor confocal scanning laser ophthalmoscopy in complex diagnostics of severe proliferative diabetic retinopathy]

Multicolor scanning laser ophthalmoscopy (multicolor SLO) is a new informative method of eye fundus visualization. The method is based on synchronously obtaining three separate confocal images with monochromatic laser sources - blue (488 nm), green (515 nm) and infrared (820 nm), which are then combined into one in the Multicolor mode.

PURPOSE

To evaluate the informative value of multicolor SLO in a complex examination of patients with severe proliferative diabetic retinopathy (PDR).

MATERIAL AND METHODS

A total of 46 patients (62 eyes) aged 19 to 75 years with severe PDR was examined. All patients had massive growth of proliferative tissue on the eye fundus, which caused traction deformation and/or retinal detachment in the posterior pole. Optical mediums of the eyes were sufficiently transparent to obtain high quality images. All patients underwent color photo-registration of the fundus, fluorescein angiography (FA), optical coherence tomography (OCT) and multicolor SLO under drug-induced mydriasis.

RESULTS

Pseudo-volumetric images obtained with multicolor SLO allow visualization of of preretinal proliferative membranes and their structure, the degree of their vascularization, the anatomical features of their attachment to retina, and the occluded vessels on fundus periphery. Being an additional option on scanning laser ophthalmoscope, the technique does not require special equipment, which enables several separate examinations, including OCT and FA, to be performed on a single device.

CONCLUSION

Multicolor SLO is a promising new method of visualizing structures of the eye fundus and can be successfully used in complex diagnostics, monitoring and preoperative preparation of patients with severe PDR.

Comparison of MultiColor fundus imaging and colour fundus photography in the evaluation of epiretinal membrane

PURPOSE

To compare MultiColor fundus imaging (MC) and colour fundus photography (CFP) for the evaluation of epiretinal membrane (ERM).

METHODS

In this retrospective study, 192 eyes (181 patients) that underwent vitrectomy for ERM were imaged using Spectralis optical coherence tomography (for MC) and AFC-210 digital camera (for CFP) 1 week before vitrectomy. Two investigators independently determined the rate of delineability and ERM area for each modality.

RESULTS

The intergrader agreement rates for delineability were very high for both image modalities. The rate of delineability of ERM (%) was higher for MC than for CFP, for both investigators [70.8% versus 52.6% and 73.4% versus 53.6% (both p -)]. Epiretinal membrane (ERM) area measurement showed high agreement between investigators for MC (p = 0.466) but differed significantly between the investigators for CFP (p -). The ERM area determined on MC was significantly wider than that on CFP for both investigators (p - for investigator 1 and p - for investigator 2).

CONCLUSION

The ERM area is more clearly detectable and widely demarcated in MC than in CFP images. MultiColor imaging (MC) may be more sensitive and accurate for early detection of ERM and ERM area measurement.

Utility of multicolor optic disc photography in evaluation of glaucomatous optic disc in myopic eyes: A novel approach

Interpretation of optic disc cupping and neuroretinal rim is challenging in myopic eyes because of large, shallow, and tilted disc, myopic crescent, and macular degeneration. Color and red-free optic disc photographs do not reveal the cup/disc ratio often in myopic eyes. We report characteristics of multicolor optic disc photography in three myopic eyes. All eyes underwent multicolor imaging Spectralis SDOCT system (Heidelberg Engineering, Germany). Owing to use of three laser lights in a confocal design, multicolor optic disc photography was able to delineate the neuroretinal rim and optic cup more clearly than color and red-free optic disc photographs.

Validation of Multicolor Imaging of Diabetic Retinopathy Lesions Vis a Vis Conventional Color Fundus Photographs

BACKGROUND AND OBJECTIVE

To analyze the visibility of various diabetic retinopathy lesions in multicolor imaging (MCI) and compare them to corresponding color fundus photography (CFP).

PATIENTS AND METHODS

Retrospective review of 130 eyes of 65 consecutive patients with diabetic retinopathy who underwent multicolor confocal scanning laser ophthalmoscopy and CFP.

RESULTS

Hard exudates (Hex) were seen in 74 eyes (71.2%). In all 74 eyes, Hex were visible on both CFP and MCI. Among other color channels, Hex were picked up most in green reflectance (GR) images in 73 eyes (70.2%). Cotton-wool spots (CWS) were picked up in 29 eyes (27.9%) on MCI and in 27 eyes (26%) on CFP. In both GR and blue reflectance (BR) imaging, they were equally picked up in 29 eyes (27.9%). Retinal hemorrhages were picked up in 83 eyes (79.8%) on MCI and in 82 eyes (72.8%) on CFP. Among other channels, they were picked up most in GR images in 81 (77.9%) eyes. Hex, CWS, and hemorrhages were seen better on MCI and in GR images as compared to CFP, BR, and infrared imaging, respectively. With CFP as the comparator, the sensitivity and specificity of MCI to detect of these lesions were more than 90%.

CONCLUSIONS

The authors' pilot study validates the efficacy of MCI in picking up lesions of DR vis a vis CFP. MCI has potential to replace CFP in clinical and DR screening setting. [Ophthalmic Surg Lasers Imaging Retina. 2019;50:8-15.].

Confocal infrared imaging with optical coherence tomography provides superior detection of a number of common macular lesions compared to colour fundus photography

PURPOSE

To compare diagnostic accuracy of confocal infrared reflectance (IR), with and without optical coherence tomography (OCT), to colour fundus photography (CFP) in the Northern Ireland Cohort for the Longitudinal Study of Ageing (NICOLA) Study.

METHODS

Cross-sectional observational study of participants in NICOLA. CFP, IR and IR/OCT of 640 eyes were graded for hard, soft and reticular pseudodrusen; geographic atrophy; choroidal neovascularisation; naevus; epiretinal membrane; and haemorrhages. Test characteristics (sensitivity and specificity) for each imaging modality with respect to each retinal feature were calculated.

RESULTS

With CFP as the reference standard, sensitivity of IR by itself ranged from 75% for RPD to 93.5% for hard drusen and specificity was above 90% for all features except hard drusen (71.7%). For IR combined with OCT, sensitivity ranged from 80% for choroidal neovascularisation to 96.5% for hard drusen. When IR alone was the reference standard, CFP sensitivity was high for naevi (97.5%) but reduced markedly for epiretinal membrane (48.5%). When the combination of IR and OCT was the reference standard, sensitivity for CFP was least for epiretinal membrane (31.5%), low for geographic atrophy and reticular pseudodrusen (77.8% and 76.2% respectively) and high for all other lesion types.

CONCLUSION

Our findings support the use of confocal IR with OCT as a screening tool for a variety of features of macular disease in community optometric practice.

Clinical application of multicolor optical coherence tomography in the diagnosis of retinal pathologies

Objective:

To assess the clinical application of multicolor optical coherence tomography (OCT) using confocal scanning laser ophthalmoscopy (cSLO) in different retinal pathologies.

Methods:

This observational study was conducted at the Layton Rahmatullah Benevolent Trust (LRBT), Free Base Eye Hospital, Karachi, from April 2018 to June 2018. It includes 36 patients suffering from different retinal pathologies including diabetic retinopathy, age related macular degeneration, and vitreomacular interface disorders using multicolor optical coherence tomography as a screening tool.

Results:

It was found that automated eye tracking system of this new version tool enables ophthalmologists to take high-resolution cSLO reflectance images. The light scatter can be avoided with the use of confocal optics. Appearances of pigment changes and hemorrhages were some of the differences found when compared to the conventional CFP. About 20% in AMD, 37.5% with diabetes and 100% patients with vitreomacular interface disorders could have be easily missed by CFP.

Conclusions:

Multicolor OCT can provide information and figures far more authoritatively than the conventional CFP, which is highly affected by media opacities. To interpret Multicolor OCT ophthalmologists should be watchful with plenty of understanding.

Ability of MultiColor scanning laser ophthalmoscope to detect non-glaucomatous retinal nerve fiber layer defects in eyes with retinal diseases

PURPOSE

To compare the ability of ocular fundus images obtained by Spectralis MultiColor scanning laser ophthalmoscope (MC-SLO) to that obtained by conventional color fundus images (CF) in detecting non-glaucomatous nerve fiber layer defects (NFLDs).

METHODS

A cross-sectional, retrospective study. Patients with retinal diseases who had ocular examination with both the MC-SLO and CF instruments at the Kagoshima University from December 2016 to February 2017 were studied. Eyes that had NFLDs with non-glaucomatous optic discs were analyzed. The visibility of the NFLDs was classified into three grades: grade 0, not visible; grade 1, barely visible; and grade 2, clearly visible. The NFLD grade for blue, green, and red scanning lights of the MC-SLO, merged images with three wavelengths and the color and red-free images were determined by two ophthalmologists. These scores were compared by Steel-Dwass tests.

RESULTS

Thirty-one eyes of 26 patients with a mean age of 63.1 ± 11.2 years were studied. There were 14 eyes with diabetic retinopathy, 11 eyes with age-related macular degeneration, 3 eyes with a branch retinal vein occlusion, and 3 eyes with an epiretinal membrane/macular hole. Both the intra-rater (0.631-0.790) and inter-rater (0.637-0.733) agreements were good. NFLDs were detected by the blue wavelength in all cases and by green wavelength and merged wavelengths in 90.3% of the images. The mean NFLD grade was 1.58 ± 0.49 for blue light images, 1.13 ± 0.54 for green light images, 0.07 ± 0.24 for red light images, and 1.16 ± 0.56 for merged images. The NFLD score for blue wavelength was significantly higher than that for green and red wavelength images (P < 0.05 and P < 0.01) but not significantly higher than that for the merged images. NFLDs were detected in 12 eyes (38.7%) in the color images and 16 eyes (51.6%) in the red-free images. The NFLD score for the CF and the red-free image was 0.41 ± 0.55 and 0.70 ± 0.67 which is significantly lower than that of blue MC-SLO images.

CONCLUSION

The images obtained by MC-SLO are superior to that obtained by CF in detecting NFLDs in eyes with retinal diseases. We recommend MC-SLO imaging to screen for NFLDs in eyes with retinal diseases.

Measurement of size of pigmented choroidal nevus: Superiority of multicolor imaging compared to conventional color fundus photography

Choroidal nevi are benign fundus lesions that require regular follow with documentation. Conventional color fundus photography (CFP) has traditionally been used to images these lesions. Multicolor imaging (MCI) available on Spectralis spectral domain optical coherence tomography system is increasingly been tested vis-à-vis conventional CFP in various retinal diseases. We present data of the right eye of a 59-year-old gentleman with choroidal nevus who underwent conventional CFP as well as MCI. Nevus appeared orange red on MCI and its size appeared larger than the same measured on conventional CFP. We also report infrared reflectance and near infrared autofluorescence features of choroidal nevus.

Multicolor imaging for retinal nerve fiber layer defect in glaucoma

Glaucoma is a progressive optic neuropathy associated with irreversible loss of retinal ganglion cells (RGC). This emblematic localized retinal nerve fiber layer defect (RNFLD) can be the earliest sign to detect the ongoing glaucomatous damage. Slitlamp biomicroscopy [90D & 78D], colour and redfree fundus photography, OCT & HRT are used conventionally for early detection of RNFLD. Multicolour Imaging (MCI) is a new non-invasive retinal imaging modality available in Spectralis platform which simultaneously acquires three reflectance images of the retina using three individual lasers producing a composite image thereby allowing analysis of changes at various levels within the retina. MCI provides sharper image, enables imaging through small pupil and hazy media. Current report describes 2 cases where in MCI proved superior to CFP and conventional redfree photograph in delineating area of RNFLD. This is the first report of MCI in RNFL imaging. The present report highlights the role of MCI in detection of RNFLD.

Multimodal imaging characteristics of hydroxychloroquine retinopathy

Hydroxychloroquine (HCQ) is known to cause retinal toxicity. Early detection of the toxicity is necessary to stop the drug in time. Multicolor imaging (MC) is a new noninvasive retinal imaging modality that simultaneously acquires three reflectance images of the retina using three individual lasers producing a composite image, thereby allowing analysis of changes at various levels within the retina. It is a new and promising addition to the retinal imaging armory. MC characteristics of HCQ toxicity are hitherto unreported. A 61-year-old female presented with history of HCQ intake (400 mg/day) for the last 6 years. She had retinopathy in both eyes. Multicolor composite image showed circumscribed perifoveal arcuate area of darkening, and infrared reflectance showed speckled hyperreflecetance in both eyes. MC imaging shows definite changes in HCQ toxicity, and it might emerge as a possible screening tool in future.

Tear film evaluation by scanning laser ophthalmoscopy during retinal imaging

Purpose:

Herein, we describe a novel finding which appears as a reticular pattern on multicolor confocal scanning laser ophthalmoscopy image during routine imaging of retina and we aim to show whether there is an association between this pattern and dry eye findings.

Materials and methods:

A total of 162 eyes of 81 patients that were scheduled for a routine retinal imaging by scanning laser ophthalmoscopy at a vitreoretinal practice underwent dry eye evaluation including corneal and conjunctival lissamine green staining, fluorescein staining, tear break-up time, and tear meniscus height measurement before acquiring any images. Then, multicolor images were taken and graded for the severity of reticular pattern.

Results:

Among 150 eyes of 81 patients with gradable multicolor imaging, 45 eyes (30%) had some reticular pattern on multicolor image. Severity of reticular pattern on multicolor imaging was significantly correlated with total lissamine score (rho = 0.378, p = 0.007) and tear meniscus height (rho = −0.408, p = 0.011). Furthermore, they were found to be the best set of predictors for the severity pattern on multicolor imaging (odds ratio = 1.30, 95% confidence interval = 1.01–1.37, p = 0.027 and odds ratio = 0.25, 95% confidence interval = 0.128–0.342, p < 0.001, respectively).

Conclusion:

Reticular pattern seen on multicolor image while acquiring retinal images using scanning laser ophthalmoscopy may be related to tear film instability. Further modulations of the scanning laser ophthalmoscopy instrument will likely improve this indicator of dry eye syndrome.

Clinical application of multicolour scanning laser imaging in diabetic retinopathy

To compare the visualization of the lesions of diabetic retinopathy (DR) using multicolour scanning laser imaging (MSLI) and conventional colour fundus photography (CFP). The paired images of diabetic patients who underwent same-day MSLI and CFP examinations were reviewed. Combined multicolour (MC) images were acquired simultaneously using three laser wavelengths: blue reflectance (BR, λ = 488 nm), green reflectance (GR, λ = 518 nm) and infrared reflectance (IR, λ = 820 nm). The number of positive DR lesions was calculated using fundus fluorescein angiography as the reference standard. The visibility of the microaneurysms (Mas) was graded using a scale, and the number of Mas for each method was counted by two masked readers. Eighty eyes of 42 diabetic patients were included. The average grading score for Mas visualization was significantly higher with MC (1.50 ± 0.71) and GR (1.55 ± 0.69) than with CFP (0.95 ± 0.81). The average number of Mas was also significantly higher with MC (11.41 ± 14.02) and GR (11.93 ± 13.43) than with CFP (6.43 ± 9.39). The number of positive Mas, diabetic macular edema (DME) and epiretinal membranes (ERM) were significantly higher with MC than CFP (P < 0.05), while the numbers of cotton wool spots, haemorrhages, hard exudates, venous beading and abnormal new vessels were not significantly different (P > 0.05). Mas and ERM were most effectively detected on GR images, and an elevated greenish shift was clearly visualized in patients with DME on the MC images. MSLI can effectively visualize Mas and other pathological lesions of DR compared with CFP. MSLI with superior resolution may be a useful complement for DME and ERM detection.

Comparison of conventional color fundus photography and multicolor imaging in choroidal or retinal lesions

PURPOSE

Our purpose was to compare the characteristics of the retinal and choroidal lesions including choroidal nevus, choroidal melanoma and congenital hypertrophy of the retina pigment epithelium using conventional color fundus photography (CFP) and multicolor imaging (MCI).

METHODS

The paired images of patients with retinal or choroidal lesions were assessed for the visibility of lesion's border, halo and drusen using a grading scale (0-2). The area of the lesion was measured on both imaging modalities. The same grading was also done on the individual color channels of MCI for a further evaluation.

RESULTS

Thirty-three eyes of 33 patients were included. There were no significant differences in the mean border, drusen and halo visibility scores between the two imaging modalities (p = 0.12, p = 0.70, p = 0.35). However, the mean area of the lesion was significantly smaller on MCI than that on CFP (14.9±3.3 versus 18.7±3.4 mm², p = 0.01).

CONCLUSION

The appearance of choroidal and/ or retinal lesions on MCI may be different than that on CFP. Though MCI can provide similar information with CFP for the features of retinal and/ or choroidal lesions including border, halo and drusen; the infrared light reflection on MCI underestimates the extent of the choroidal lesion by 33%.