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Retinopathy of prematurity(ROP)is the primary cause of preventable childhood blindness. It is hard to screen, diagnose and objectively evaluate. There are various modalities for ROP screening, including various contact or non-contact imaging devices, smart phone-based fundus photography, and artificial intelligence-based fundus image analysis. The diagnosis of ROP is based on visualization and recording of the entire retinal fundus of ROP, which is also the basis for subsequent screening, treatment assessment. Fundus screening is critical for early recognition and facilitates early detection and prompt referral. Potential features may be found by analyzing and summarizing the characteristics of ROP fundus images. Subsequently, timely and targeted ROP prevention and treatment could be performed. Artificial intelligence promotes automatic, quantifiable and objective diagnosis of ROP. This article reviews commonly used clinical fundus examination methods and fundus image characteristics of ROP and summarizes the latest research progress on the application of artificial intelligence in the automatic diagnosis of ROP.
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Adaptive optics(AO)is a technique used to optimize the functionality of optical systems through the reduction of wavefront distortion and optical aberrations. AO-based retinal imaging reduces the occurrence of optical aberrations in the refractive system, consequently improving the resolution and overall quality of retinal imaging. As a result, AO-based retinal imaging has potential wide-ranging application in ophthalmology. A combination of AO, fundus camera, scanning laser ophthalmoscope, optical coherence tomography technique and optical coherence tomography angiography, can be applied to observe the distribution, morphology and function of retinal cone cells in the healthy retinal, and to comprehend the shape and perfusion of retinal vessels in the fine vascular layer. With this technique, it can also possible to perform qualitative and quantitative analysis of the number and shape of cells in the ocular fundus, the cribriform plate, and the microscopic structures of the retinal microvascular system and nerve tissue. It can be expected as a novel tool for the early diagnosis, follow-up of therapy effects, and identification of progression of ophthalmic diseases such as diabetic retinopathy, age-related macular degeneration, glaucoma and hereditary retinal diseases.
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Adaptive optics (AO) can measure and correct wavefront aberrations in real time, which enables the optical system to adapt to external changes and maintain excellent optical performance, and has been gradually paid attention in the field of ophthalmology.AO technology can carry out optometry according to wavefront aberrations to improve the efficiency and accuracy of subjective and objective refraction, eliminate the influence of ocular aberrations on retinal imaging, provide more accurate data for the evaluation of optic nerve function, improve the effectiveness of visual perception training and provide vision care and treatment for special people, as well as simulate and predict postoperative visual outcome and give personalized schemes for refractive surgery and intraocular lens implantation.Moreover, AO combined with optical coherence tomography, optical scanning laser ophthalmoscope, and confocal scanning laser ophthalmoscope, can realize fundus imaging and retinal vascular imaging in real time, provide better sensitivity and resolution of retinal detection, distinguish fine details of retinal vessels and cone cells, and characterize retinal pigment epithelium topology and deformation, the application of which in posterior segment laser surgery, glaucoma diagnosis and follow-up, color blindness and retinal physiological activity research has been attracting attention.In this article, the principle and application of AO in ophthalmology were briefly reviewed.
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Purpose: To evaluate the sensitivity and specificity of smartphone-based nonmydriatic (NM) retinal camera in the detection of diabetic retinopathy (DR) and sight-threatening DR (STDR) in a tertiary eye care facility. Methods: Patients with diabetes underwent retinal photography with a smartphone-based NM fundus camera before mydriasis and standard 7-field fundus photography with a desktop mydriatic fundus camera after mydriasis. DR was graded using the international clinical classification of diabetic retinopathy system by two retinal expert ophthalmologists masked to each other and to the patient's identity. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) to detect DR and STDR by NM retinal imaging were assessed. Results: 245 people had gradable images in one or both eyes. DR and STDR were detected in 45.3% and 24.5%, respectively using NM camera, and in 57.6% and 28.6%, respectively using mydriatic camera. The sensitivity and specificity to detect any DR by NM camera was 75.2% (95% confidence interval (CI) 68.1–82.3) and 95.2% (95%CI 91.1–99.3). For STDR the values were 82.9% (95% CI 74.0–91.7) and 98.9% (95% CI 97.3–100), respectively. The PPV to detect any DR was 95.5% (95% CI 89.8–98.5) and NPV was 73.9% (95% CI 66.4–81.3); PPV for STDR detection was 96.7% (95% CI 92.1–100)) and NPV was 93.5% (95% CI 90.0–97.1). Conclusion: Smartphone-based NM retinal camera had fairly high sensitivity and specificity for detection of DR and STDR in this clinic-based study. Further studies are warranted in other settings.
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Purpose: To describe the swept-source optical coherence tomography (SS-OCT) features of regressed macular retinoblastoma (RB). Methods: A cross-sectional observational study was carried out in 13 patients with regressed macular RB with good fixation in at least one eye. Fundus photography and SS-OCT were documented. High-resolution scans with good signal strength were selected. The types of clinical regression and SS-OCT characteristics of the regressed lesions (presence of vitreous detachment, intratumor schisis/cavitation, calcification, foveal dip, and OCT pattern) were noted. Results: Of the 13 eyes, 7 (53%) were group B, 4 (30%) were group C, and 2 (17%) were group D. Lesion involving fovea was seen in seven eyes (53%). On SS-OCT, the lesion was isodense to hyperdense in all cases. Three patterns of regressed RB were noted on OCT. Intralesion calcification was noted in eight cases. Subretinal fluid was not detected in any of the cases. Conclusion: SS-OCT is a useful technology to image and analyze cases of regressed macular RB including large lesions. SS-OCT system helps in successful imaging even in smaller children.
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The advances in treating blinding conditions often depends on the development of new techniques that allows early detection, treatment, and follow-up of the disease. Functional changes often precede structural changes in many retinal disorders. Therefore, detecting these changes helps in early diagnosis and management, with the intention of preventing permanent morbidity. The Retinal Functional Imager (RFI) is a non-invasive imaging system that allows us to assess the various functional parameters of the retina. The RFI quantitatively measures the retinal blood-flow velocity, oxygen saturation, metabolic demand and generates a non-invasive capillary perfusion map that provides details similar to a fluorescein angiography. All of these parameters correlate with the health of the retina, and are known to get deranged in retinal disease. This article is a brief review of published literature on the clinical utility of the RFI.
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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.
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Purpose: The aim of this study is to analyze the yield of retinal images obtained in a rural diabetes eye care model. Methods: An analysis of a sample of nonmydriatic fundus photography (NMFP) of posterior segment ophthalmic images, obtained by an indigenous equipment (3 nethra-Forus Royal), was done in a district-wide rural diabetic retinopathy (DR) screening program; a trained optometrist did the initial image grading. DR and diabetic macular edema (DME) were classified based on international DR and DME severity scale. The agreement between the optometrist and retina specialist was very good (? = 0.932; standard error = 0.030; 95% confidence interval = 0.874�991). Results: Posterior segment images of 2000 eyes of 1000 people with diabetes mellitus (DM) were graded. The mean age of the participants was 55.7 � 11.5 standard deviation years. Nearly 42% of the screened participants (n = 420/1000) needed referral. The most common referable posterior segment abnormality was DR (8.2%). The proportion of people with any form of DR was seen in 110/1225 eyes, and sight-threatening DR was seen in 35/1225 eyes. About 62% of posterior segment images were gradable. The reasons for ungradable posterior segment images (34%) were small pupil, unfocused/partially available field of images, and cataract. Conclusion: A NMFP model was able to detect referable posterior segment abnormalities in a rural diabetes eye care program. Reasons found for ungradability of images in the present study can be addressed while designing future DR screening programs in the rural areas.
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·AIM:To compare the application effect on patients with retinopathy of prematurity (ROP) screened by wide-angle digital retinal imaging system (RetCam) and binocular indirect ophthalmoscope (BIO). ·METHODS:Totally 1624 cases(3248 eyes) of premature infants were detected by RetCam and BIO in our hospital from May 2014 to May 2017. The screening results of ROP and occurrence of adverse events were compared between two checking methods. ·RESULTS: In the 1 624 cases (3248 eyes) of premature infants,196 cases (392 eyes) of premature infants were detected by RetCam and 189 cases (378 eyes) of premature infants were detected by BIO, there was no statistical significance on staging results and partition pathological results between RetCam and BIO (P>0.05). Taking inspection result of BIO as standard, the sensibility, specificity, false positive rate and positive predictive value was 100. 00%, 99. 51%, 3. 57% and 96.43%, respectively. The adverse event rate of RetCam and BIO was 0.18% and 0.22%, respectively, there was no statistical significance (P>0.05). ·CONCLUSION:RetCam and BIO have similar application efficacy for screening ROP, and RetCam could take the place of BIO as the screening method of ROP.
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·AIM:To investigate and compare the application of two screening models in the detection of retinopathy of prematurity (ROP). ·METHODS: The clinical data of 600 premature infants (1200 eyes) who underwent screening of eye diseases in the Department of Ophthalmology during the period from January 2016 to January 2017 were analyzed retrospectively. The fundus lesions were examined with binocular indirect ophthalmoscope (BIO) and the third generation of wide-angle digital retinal imaging system (RetCam Ⅲ). The examination results and adverse events during operation were statistically analyzed. ·RESULTS:In 1200 eyes of 600 patients,the probabilities of ROP detected by BIO and RetCam Ⅲ were 10.92% and 10.75%, respectively (P>0.05). With BIO as the golden standard, the accuracy, sensitivity, specificity, positive predictive value and negative predictive value of RetCam Ⅲ in examining ROP were 98.67%, 93.13%, 99.35%, 94.57% and 99.16%, respectively. There was no significant difference in the stage of ROP detected by BIO or RetCam Ⅲ (P>0.05). The probabilities of non-ROP lesions examined by BIO and RetCam Ⅲ were 4.83% and 4.58%, respectively (P>0.05). With BIO as the golden standard, the accuracy, sensitivity, specificity, positive predictive value and negative predictive value of RetCam Ⅲ in examining fundus non-ROP diseases were 99.67%, 94.83%, 99.91%, 98.21% and 99.74%, respectively. During the screening of BIO and RetCam Ⅲ,there were 17 cases (2.83%) and 7 cases(1.17%) with adverse events, respectively (P<0.05).·CONCLUSION: The examination results of RetCam Ⅲ are basically the same as those of BIO for ROP and non-ROP diseases. However,RetCam Ⅲ has more advantages in reducing adverse events during operation.
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Background Cystoid macular edema (CME) is caused by many fundus diseases.The noninvasive clinical diagnosis methods for CME are conventional color fundus photography up to now.However,these images can not display the CME range well.Confocal scanning laser ophthalmoscope (cSLO) based retinal imaging can provide clear picture with high contrast.However,whether cSLO imaging is feasible in the quantitative assessment of CME remains unclear.Objective This study was to image the boundary of CME and assess the quantification of CME image from cSLO imaging technology.Methods A series case-observational study was designed.This study protocal was approved by Ethic Committee of Beijing Tongren Hospital.cSLO based retinal imaging technology was carried out on consecutive 24 eyes of 24 patients with clinically diagnosed and OCT confirmed CME in Beijing Tongren Eye Center from August to December 2015 under the informed consent of each individual.The radial scan range was 45°× 45 ° and the line scan level was 49 at macula area.The pseudocolar image,green light reflective image (532 nm) and infrared reflective image (785 nm) were collected.The imaging was analyzed by EasyScan software (version 1.2.2).Fundus color photography and SD-OCT were carried out in each patient.The images were graded by specialists according to the SD-OCT cross sectional results.Results The primary causes of CME included epiretinal membrane (10 eyes),branch retinal vein occlusion (BRVO) (6 eyes),central retinal vein occlusion (CRVO) (4 eyes),diabetic retinopathy (DR) (3 eyes) and CRVO with BRVO (1 eye).A CME image was exhibited on the fundus color photogram with the obscure boundary;while the clear range of CME was displayed by the cSLO imaging.The mean score of CME from pseudocolar image,green light reflective image and infrared reflective image was 3.21±0.78,2.67±0.96 and 2.54±0.83,respectively,which was significantly higher than 1.33±0.82 from the fundus color photography (all at P＜0.01).Conclusions In CME patients,the imaging quality from cSLO-based retinal imaging technology is better than that from traditional fundus color photography.Combined with SD-OCT sectional scan analysis,cSLO-based retinal imaging technology may offer a method to observe and record more fundus details for CME diagnosis.
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Newer retinal imaging technologies help us in understanding the pathogenesis of many retinal pathologies,such as diabetic retinopathy,age related macular degeneration,glaucoma and uveitis.Early detection of these retinal diseases can prevent the onset of progressive vision loss,and aid in the development of new treatment options.Retinal functional imager (RFI) is an unique and noninvasive functional imaging system.Unlike most of the available newer retinal imaging tools,the RFI not only shows retinal structural changes,but can directly monitor functional changes and measure hemodynamic parameters,such as retinal bloodflow velocity,oximetric state,etc.This article reviews the utility progress of RFI in various retinal diseases.
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This article describes the method to make a do it yourself smartphone‑based fundus camera which can image the central retina as well as the peripheral retina up to the pars plana. It is a cost‑effective alternative to the fundus camera.
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Purpose: To evaluate the correlation between retinal sensitivity and cystoid space characteristics in eyes with diabetic macular edema (DME). Materials and Methods: Prospective cross‑sectional study of 22 subjects with DME (32 treatment‑naïve eyes). All study subjects underwent complete ophthalmic examination, including slit‑lamp biomicroscopy and dilated fundus examination. All subjects underwent spectral domain optical coherence tomography (SD‑OCT) and microperimetry (MP). Intraretinal cystoid space (ICS) volume was generated after manual delineation of cystoid space boundaries using the three‑dimensional‑OCT software. Various SD‑OCT parameters, including retinal thickness, retinal volume, cystoid space volume, cystoid space intensity, and outer retinal structure integrity, were correlated with MP parameters and best‑corrected visual acuity (BCVA). Results: Subject’s mean age was 57 ± 9 years. The mean logarithm of minimum angle of resolution BCVA was 0.4 ± 0.2. The intraclass correlation coefficient for inter‑ and intra‑grader assessment of cystoid space volume by manual delineation was 0.99 and 0.99, respectively. Mean total ICS volume was 0.4 ± 0.4 mm3 and for the foveal center, subfield was 0.1 ± 0.1 mm3. Mean retinal sensitivity was 12.89 ± 10 dB; however, foveal retinal sensitivity was 12.3 ± 11.1 dB. We found no significant correlation between BCVA and total cystoid space volume (r = 0.33, P = 0.06). Correlation between total retinal sensitivity and total ICS was negative and nonsignificant (r = −0.17, P = 0.36). Correlation between foveal retinal sensitivity and foveal cystoid space intensity was moderate and marginally significant (r = −0.43, P = 0.05). Conclusion: Total cystoid space volume was not significantly correlated with BCVA or total retinal sensitivity in subjects with DME. Foveal cystoid space optical intensity was negatively correlated with foveal retinal sensitivity. These findings suggest further investigation of cystoid space characteristics in the setting of DME may be of value.
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Diabetic retinopathy and diabetic macular edema (DME) are leading causes of blindness throughout the world, and cause significant visual morbidity. Ocular imaging has played a significant role in the management of diabetic eye disease, and the advent of advanced imaging modalities will be of great value as our understanding of diabetic eye diseases increase, and the management options become increasingly varied and complex. Color fundus photography has established roles in screening for diabetic eye disease, early detection of progression, and monitoring of treatment response. Fluorescein angiography (FA) detects areas of capillary nonperfusion, as well as leakage from both microaneurysms and neovascularization. Recent advances in retinal imaging modalities complement traditional fundus photography and provide invaluable new information for clinicians. Ultra‑widefield imaging, which can be used to produce both color fundus photographs and FAs, now allows unprecedented views of the posterior pole. The pathologies that are detected in the periphery of the retina have the potential to change the grading of disease severity, and may be of prognostic significance to disease progression. Studies have shown that peripheral ischemia may be related to the presence and severity of DME. Optical coherence tomography (OCT) provides structural detail of the retina, and the quantitative and qualitative features are useful in the monitoring of diabetic eye disease. A relatively recent innovation, OCT angiography, produces images of the fine blood vessels at the macula and optic disc, without the need for contrast agents. This paper will review the roles of each of these imaging modalities for diabetic eye disease.
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The peripheral retina is the site of pathology in many ocular diseases and ultra‑widefield (UWF) imaging is one of the new technologies available to ophthalmologists to manage some of these diseases. Currently, there are several imaging systems used in practice for the purpose of diagnostic, monitoring disease progression or response to therapy, and telemedicine. These include modalities for both adults and pediatric patients. The current systems are capable of producing wide‑ and UWF color fundus photographs, fluorescein and indocyanine green angiograms, and autofluorescence images. Using this technology, important clinical observations have been made in diseases such as diabetic retinopathy, uveitides, retinal vascular occlusions and tumors, intraocular tumors, retinopathy of prematurity, and age‑related macular degeneration. Widefield imaging offers excellent postoperative documentation of retinal detachment surgery. New applications will soon be available to integrate this technology into large volume routine clinical practice.
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Fundus autofluorescence (FAF) is a relatively new imaging technique that can be used to study retinal diseases. It provides information on retinal metabolism and health. Several different pathologies can be detected. Peculiar AF alterations can help the clinician to monitor disease progression and to better understand its pathogenesis. In the present article, we review FAF principles and clinical applications.