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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). 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. 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

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.

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.

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.

Purpose: This study was conducted to evaluate the ability of multicolor (MC)–green re flectance (GR) imaging in detecting retinal non- perfused areas (RNPAs) of eyes with diabetic retinopathy (DR). Materials and Methods: Fifty-five degrees fundus fluorescein angiography (FA) and MC imaging were performed in eyes with DR. Images were divided into four fields as macular, nasal, superior temporal, and inferior temporal. To determine the presence and size of RNPAs, FA images were examined by a retina specialist and MC–GR images were examined independently by two masked retina specialists. The compliance of RNPAs in FA and MC–GR images and the agreement of retina specialists were analyzed. Results: The FA and MC–GR images of the 178 eyes were analyzed. When GR images were compared to FA images in terms of RNPAs, sensitivity was 87%; specificity was 89%; the positive predictive value was 92%; the negative predictive value was 83%; and the accuracy was 87%. A substantial agreement was observed between two retina specialists in all retinal fields. Conclusion: This study showed that 55º MC–GR imaging could be an alternative to FA in the evaluation of RNPAs. This study is the first known to explore this issue and needs to be supported and developed with new investigations.

Multiparametric fluorescence imaging through CODEX allows the simultaneous imaging of many biomarkers in a single tissue section. While the digital fluorescence data thus obtained can provide highly specific characterizations of individual cells and microenvironments, the images obtained are different from those usually interpreted by pathologists (i.e., hematoxylin and eosin [H&E] slides and 3,3′-diaminobenzidine-stained immunohistochemistry slides). Having the fluorescence data plus coregistered H&E or similar data could facilitate the adoption of multiparametric imaging into regular workflows, as well as facilitate the transfer of algorithms and machine learning previously developed around H&E slides. Since commercial CODEX instruments do not produce H&E-like images by themselves, we developed a staining protocol and associated image processing to make “virtual H&E” images that can be incorporated into the CODEX workflow. While there are many ways to achieve virtual H&E images, including the use of a fluorescent nuclear stain and tissue autofluorescence to simulate eosin staining, we opted to combine fluorescent nuclear staining (through 4′,6-diamidino-2-phenylindole) with actual eosin staining. We also output images derived from fluorescent nuclear staining and autofluorescence images for additional evaluation.

International audience; Multicolor multiphoton microscopy is experimentally demonstrated for the first time on a spectral bandwidth of excitation of 300 nm (full width half maximum) thanks to the implementation a nanosecond supercontinuum (SC) source compact and simple with a low repetition rate. The interest of such a wide spectral bandwidth, never demonstrated until now, is highlighted in vivo: images of glioma tumor cells stably expressing eGFP grafted on the brain of a mouse and its blood vessels network labelled with Texas Red® are obtained. These two fluorophores have a spectral bandwidth covering the whole 300 nm available. In parallel, a similar image quality is obtained on a sample of mouse muscle in vitro when excited with this nanosecond SC source or with a classical high rate, femtosecond and quasi monochromatic laser. This opens the way for (i) a simple and very complete biological characterization never performed to date with multiphoton processes, (ii) multiple means of contrast in nonlinear imaging allowed by the use of numerous fluorophores and (iii) other multiphoton processes like three-photon ones.

Purpose: To describe the multicolor imaging (MCI) features in a series of patients diagnosed with a choroidal nevus and compare it vis-à-vis color fundus photography (CFP) in identifying the lesion. Methods: In this retrospective, descriptive case series at a tertiary referral center in South India, all patients diagnosed with the choroidal nevus underwent CFP, optical coherence tomography, MCI, and infrared reflectance (IR) imaging. Results: In this study, we found that on MCI, the choroidal nevus could be identified in only six of the 12 eyes. The lesions were seen as an area of hyperreflectance on IR image and orange-colored lesion on multicolor image. In one eye, there was a mixed pattern of hyper and hyporeflectance on IR imaging. The remaining five eyes with choroidal nevus lesions were not identified on MCI. Conclusion: The variable features of the choroidal nevus on MCI are most likely due to the variable melanin content within the nevus cells. Further studies are needed to validate these findings.

Surface-enhanced Raman spectroscopy (SERS) has proven a powerful tool for multiplex detection and imaging due to its narrow peak width and high sensitivity. However, conventional SERS reporters are limited to thiolated compounds, which have limitations such as chemical stability and spectral overlap. Here, we used alkyne- and nitrile-bearing molecules to directly fabricate a set of SERS tags for multiplex imaging. The alkyne and nitrile groups act as both the anchoring points to interact with gold nanoparticle (AuNP) surfaces and the reporters exhibiting strong and nonoverlapping signals in the cellular Raman-silent region. The SERS tags were subsequently modified with different antibodies for multicolor imaging of cancer cells and human breast cancer tissues. The reporters have a simple and readily accessible structure, hence providing new opportunities to prepare SERS nanoprobes.

In vivo multicolor imaging is important for monitoring multiple biomolecular or cellular processes in biology. 19F magnetic resonance imaging (MRI) is an emerging in vivo imaging technique because it can non‐invasively visualize 19F nuclei without endogenous background signals. Therefore, 19F MRI probes capable of multicolor imaging are in high demand. Herein, we report five types of perfluorocarbon‐encapsulated silica nanoparticles that show 19F NMR peaks with different chemical shifts. Three of the nanoprobes, which show spectrally distinct 19F NMR peaks with sufficient sensitivity, were selected for in vivo multicolor 19F MRI. The nanoprobes exhibited 19F MRI signals with three colors in a living mouse. Our in vivo multicolor system could be utilized for evaluating the effect of surface functional groups on the hepatic uptake in a mouse. This novel multicolor imaging technology will be a practical tool for elucidating in vivo biomolecular networks by 19F MRI.

Lipid droplets (LDs) are intracellular lipid-rich organelles that regulate the storage of neutral lipids and were recently found to be involved in many physiological processes, metabolic disorders, and diseases including obesity, diabetes, and cancers. Herein we present a family of new fluorogenic merocyanine fluorophores based on an indolenine moiety and a dioxaborine barbiturate derivative. These so-called StatoMerocyanines (SMCy) fluoresce from yellow to the near-infrared (NIR) in oil with an impressive fluorescence enhancement compared to aqueous media. Additionally, SMCy display remarkably high molar extinction coefficients (up to 390 000 M–1 cm–1) and high quantum yield values (up to 100%). All the members of this new family specifically stain the LDs in live cells with very low background noise. Unlike Nile Red, a well-known lipid droplet marker, SMCy dyes possess narrow absorption and emission bands in the visible, thus allowing multicolor imaging. SMCy proved to be compatible with fixation and le...

Retinitis pigmentosa (RP) is an inherited retinal disease caused by the degeneration of photoreceptors and retinal pigment epithelium cells within the eye. The present study aimed to evaluate the effectiveness of multicolor imaging as a novel technique for the depiction of morphological features in the macular area of patients with RP. Additionally, the correlation between the size of the macular-sparing area and the best corrected visual acuity (BCVA), central visual field function and subfoveal choroidal thickness (SFCT) was analyzed. A total of 25 individuals with RP (n=50 eyes) and 35 healthy individuals (n=70 eyes) were enrolled in the current study. Images of the macular area were captured using multicolor imaging and traditional fundus photography, and their ability to depict retinal features was compared. The size of the macular-sparing area in patients with RP was measured using built-in measurement software programs. The correlations between the macular-sparing area and the BCVA, visual field and SFCT were analyzed using a Spearman's rank correlation test. The results demonstrated that multicolor imaging revealed clinical features of the macular area in greater detail than traditional fundus photography irrespective of whether the patient also had complications, including cataracts and epiretinal membranes. Multicolor imaging clearly defined the borders of the macular-sparing area corresponding to the relatively intact outer retinal structures on optical coherence tomography images, particularly the status of the ellipsoid zone and external limiting membrane. There was a significant positive correlation between the macular-sparing area and BCVA (r=−0.631; P

Cellular functions emerge from the collective action of a large number of different proteins. Understanding how these protein networks operate requires monitoring their components in intact cells. Due to intercellular and intracellular molecular variability, it is important to monitor simultaneously multiple components at high spatiotemporal resolution. However, inherent trade-offs narrow the boundaries of achievable multiplexed imaging. Pushing these boundaries is essential for a better understanding of cellular processes. Here the motivations, challenges and approaches for multiplexed imaging of intracellular protein networks are discussed. Fil: Grecco, Hernan Edgardo. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Física; Argentina Fil: Imtiaz, S.. Institut Max Planck fur Molekulare Physiologie; Alemania Fil: Zamir, E.. Institut Max Planck fur Molekulare Physiologie; Alemania

Multiphoton microscopy is a well-established technique for biological imaging of several kinds of targets. It is classically based on multiphoton processes allowing two means of contrast simultaneously: two-photon fluorescence (TPF) and second harmonic generation (SHG). Today, the quasi exclusive laser technology used in that aim is femtosecond titanium sapphire (Ti: Sa) laser. We experimentally demonstrate that a nanosecond supercontinuum laser source (STM-250-VIS-IR-custom, Leukos, France; 1 ns, 600-2400 nm, 250 kHz, 1 W) allows to obtain the same kind of image quality in the case of both TPF and SHG, since it is properly filtered. The first set of images concerns the muscle of a mouse. It highlights the simultaneous detection of TPF and SHG. TPF is obtained thanks to the labelling of alpha-actinin with Alexa Fluor ® 546 by immunochemistry. SHG is created from the non-centrosymmetric organization of myosin. As expected, discs of actin and myosin are superimposed alternatively. The resulting images are compared with those obtained from a standard femtosecond Ti: Sa source. The physical parameters of the supercontinuum are discussed. Finally, all the interest of using an ultra-broadband source is presented with images obtained in vivo on the brain of a mouse where tumor cells labeled with eGFP are grafted. Texas Red ® conjugating Dextran is injected into the blood vessels network. Thus, two fluorophores having absorption wavelengths separated by 80 nm are imaged simultaneously with a single laser source.

International audience; Purpose:To determine the rate of reticular pseudodrusen (RPD) in age-related macular degeneration using multimodal imaging, including color fundus photography, the blue channel image of fundus photography, infrared reflectance, fundus autofluorescence, multicolor imaging, and spectral domain optical coherence tomography, as well as to compare the sensitivities and specificities of these modalities for detecting RPD.Methods:This prospective study included 243 eyes from 125 consecutive patients with age-related macular degeneration. They underwent fundus examination including color fundus photography, blue channel, infrared reflectance, fundus autofluorescence, multicolor imaging, and spectral domain optical coherence tomography in both eyes. To be considered as having RPD, eyes had to have reticular patterns on spectral domain optical coherence tomography in a large studied cube of 30 degrees x 25 degrees or on infrared reflectance with at least one other examination.Results:The mean age of the 125 patients was 81.1 years (8.1). Eighty-six patients (68.8%) were diagnosed with RPD. Spectral domain optical coherence tomography, infrared reflectance, and multicolor imaging had the highest sensitivity (99.3, 84.6, and 87.1%, respectively) and specificity (100%). The color fundus photography, blue channel, and fundus autofluorescence had lower sensitivity to detect RPD.Conclusion:Reticular pseudodrusen is frequently associated with soft drusen in patients with age-related macular degeneration. As RPD may be rarely located only in the perifoveal area, spectral domain optical coherence tomography with a larger cube (30 x 25 degrees) than that usually used (20 x 20 degrees) had the highest sensitivity and specificity to detect RPD and is recommended to optimize the rate of detection.

Understanding the complexity of the cellular environment will benefit from the ability to unambiguously resolve multiple cellular components, simultaneously and with nanometer-scale spatial resolution. Multicolor super-resolution fluorescence microscopy techniques have been developed to achieve this goal, yet challenges remain in terms of the number of targets that can be simultaneously imaged and the crosstalk between color channels. Herein, we demonstrate multicolor stochastic optical reconstruction microscopy (STORM) based on a multi-parameter detection strategy, which uses both the fluorescence activation wavelength and the emission color to discriminate between photo-activatable fluorescent probes. First, we obtained two-color super-resolution images using the near-infrared cyanine dye Alexa 750 in conjunction with a red cyanine dye Alexa 647, and quantified color crosstalk levels and image registration accuracy. Combinatorial pairing of these two switchable dyes with fluorophores which enhance photo-activation enabled multi-parameter detection of six different probes. Using this approach, we obtained six-color super-resolution fluorescence images of a model sample. The combination of multiple fluorescence detection parameters for improved fluorophore discrimination promises to substantially enhance our ability to visualize multiple cellular targets with sub-diffraction-limit resolution.

In article number https://doi.org/10.1002/advs.201700982, Juncheng Cao, Hua Li, Tiger H. Tao, and co‐workers report a realtime, multispectral terahertz imager based on a multispectral metamaterial focal plane array. Versatile imaging capabilities, including unambiguous identification of concealed substances with intrinsic terahertz characteristics and effective diagnosis of cancerous tissues without notable spectral signatures in the terahertz range, are presented, thus underscoring the utility of applying the multispectral terahertz imager for sensing, identification, and medical imaging.

Recent progress in ultrafast spectroscopy and semiconductor technology is enabling unique applications in screening, detection, and diagnostics in the Terahertz (T‐ray) regime. The promise of efficaciously operation in this spectral region is tempered by the lack of devices that can spectrally analyze samples at sufficient temporal and spatial resolution. Real‐time, multispectral T‐ray (Mul‐T) imaging is reported by designing and demonstrating hyperspectral metamaterial focal plane array (MM‐FPA) interfaces allowing multiband (and individually tunable) responses without compromising on the pixel size. These MM‐FPAs are fully compatible with existing microfabrication technologies and have low noise when operating in the ambient environment. When tested with a set of frequency switchable quantum cascade lasers (QCLs) for multicolor illumination, both MM‐FPAs and QCLs can be tuned to operate at multiple discrete THz frequencies to match analyte “fingerprints.” Versatile imaging capabilities are presented, including unambiguous identification of concealed substances with intrinsic and/or human‐engineered THz characteristics as well as effective diagnosis of cancerous tissues without notable spectral signatures in the THz range, underscoring the utility of applying multispectral approaches in this compelling wavelength range for sensing/identification and medical imaging.

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.