Comparison of two, three and four 45 degrees image fields obtained with the Topcon CRW6 nonmydriatic camera for screening for diabetic retinopathy

BACKGROUND: The use of the nonmydriatic camera is gaining increasing acceptance for the detection of diabetic retinopathy when integrated into a community-tailored program. We performed a study to evaluate the optimal number and positioning of photographic fields necessary to screen for diabetic retinopathy with the Topcon CRW6 nonmydriatic camera. METHODS: In this prospective masked cross-sectional comparative study, we compared the assessment of diabetic retinopathy using two, three or four 45 degrees fundus images (centred respectively on the disc and the macula; on the disc, on the macula and temporal to the macula; and on the disc, on the macula, temporal to the macula and superotemporal to the macula, including the superior temporal vein) acquired with the Topcon CRW6 nonmydriatic camera, with the grading of the seven standard stereoscopic 30 degrees field photographs (7SF). The study population consisted of 98 consecutive adult patients known to have type 1 or 2 diabetes mellitus who presented for the first time to the diabetic retinopathy clinic of a tertiary care centre in Montreal. All patients underwent four nonmydriatic fundus photography sessions of both eyes, 7SF photography with pupil dilation and a complete ophthalmologic examination with pupil dilation by a retina specialist. RESULTS: Compared to the 7SF, the sensitivity and specificity of screening for any retinopathy (Early Treatment Diabetic Retinopathy Study [ETDRS] grade greater than 10) using the two central fields were 95.7% and 78.1% respectively. The corresponding values with three image fields were 97.6% and 71.9%, and with four image fields, 97.6% and 65.6%. The sensitivity and specificity of screening for mild or worse disease (ETDRS grade 35 or greater) using the two central fields were 87.5% and 92.3%. The corresponding values with three image fields were 88.9% and 94.6%, and with four image fields, 88.9% and 91.9%. Poor image quality occurring with the addition of extra fields resulted in an increase of 6.2% in the rate of referral to an ophthalmologist. The use of two image fields missed no cases of retinopathy. INTERPRETATION: The use of image fields in addition to the two 45 degrees images centred on the disc and the macula on imaging with the Topcon CRW6 nonmydriatic camera did not significantly increase the sensitivity or specificity of screening for diabetic retinopathy. Contrary to the desired effect, the addition of fields resulted in diminished utility and cost-effectiveness of this screening approach.     

Screening for diabetic retinopathy using a digital non-mydriatic camera compared with standard 35-mm stereo colour transparencies

PURPOSE: To investigate the use of a digital non-mydriatic camera for determining the ETDRS clinical level of diabetic retinopathy, and to evaluate its use in a screening setting to appropriately determine the need for referral to an ophthalmologist (ETDRS level > or = 35). METHODS: A total of 83 patients with diabetes were photographed with and without pharmacological pupil dilation at an ophthalmology department using a digital non-mydriatic camera, obtaining two sets of five non-stereoscopic, 45 degree field images of each eye. ETDRS seven standard field, 35-mm stereoscopic colour fundus photographs were also obtained. A subgroup of 59 patients was photographed at an optician's shop using the digital non-mydriatic camera without pupil dilation. RESULTS: There was substantial agreement between the clinical level of diabetic retinopathy assessed from the 35-mm photographs and the digital images: the ophthalmology department (kappa = 0.76) with pupil dilation and (kappa = 0.66) without pupil dilation, respectively, and at the optician's (kappa = 0.60 without pupil dilation). With respect to the need for referral to an ophthalmologist, there was almost perfect agreement in the ophthalmology department (kappa = 0.88) with pupil dilation and (kappa = 0.84) without pupil dilation, respectively, and those taken at the optician's (kappa = 0.87 without pupil dilation). CONCLUSION: A digital non-mydriatic camera may be used in a screening situation to appropriately determine the need for referral to an ophthalmologist (ETDRS level > or = 35).     

Stereo nonmydriatic digital-video color retinal imaging compared with Early Treatment Diabetic Retinopathy Study seven standard field 35-mm stereo color photos for determining level of diabetic retinopathy

OBJECTIVE: To evaluate the ability to determine clinical levels of diabetic retinopathy, timing of next appropriate retinal evaluation, and necessity of referral to ophthalmology specialists using stereoscopic nonmydriatic digital-video color retinal images as compared with Early Treatment Diabetic Retinopathy Study (ETDRS) seven standard field 35-mm stereoscopic color fundus photographs. DESIGN: Prospective, clinic-based, comparative instrument validation study. PARTICIPANTS: Fifty-four patients (108 eyes) with type 1 or type 2 diabetes mellitus selected after chart review from a single center to include the full spectrum of diabetic retinopathy. METHODS: Nonsimultaneous 45 degrees -field stereoscopic digital-video color images (JVN images) were obtained from three fields with the Joslin Vision Network (JVN) system before pupil dilation. Following pupil dilation, ETDRS seven standard field 35-mm stereoscopic color 30 degrees fundus photographs (ETDRS photos) were obtained. Joslin Vision Network images and ETDRS photos were graded on a lesion-by-lesion basis by two independent, masked readers to assess ETDRS clinical level of diabetic retinopathy. An independent ophthalmology retina specialist adjudicated interreader disagreements in a masked fashion. MAIN OUTCOME MEASURES: Determination of ETDRS clinical level of diabetic retinopathy, timing of next ophthalmic evaluation of diabetic retinopathy, and need for prompt referral to ophthalmology specialist. RESULTS: There was substantial agreement (kappa = 0.65) between the clinical level of diabetic retinopathy assessed from the undilated JVN images and the dilated ETDRS photos. Agreement was excellent (kappa = 0.87) for suggested referral to ophthalmology specialists for eye examinations. Comparison of individual lesions between the JVN images and the ETDRS photos and for interreader comparisons were comparable to the prior ETDRS study. CONCLUSIONS: Undilated digital-video images using the JVN system were comparable photographs for the determination of diabetic retinopathy level. The results validate the agreement between nonmydriatic JVN images and dilated ETDRS photographs and suggest that this digital technique may be an effective telemedicine tool for remotely determining the level of diabetic retinopathy, suggesting timing of next retinal evaluation and identifying the need for prompt referral to ophthalmology specialists. Thus, the JVN system would be an appropriate tool for facilitating increased access of diabetic patients into recommended eye evaluations, but should not be construed as a paradigm that would replace the need for comprehensive eye examinations.     

The sensitivity and specificity of single-field nonmydriatic monochromatic digital fundus photography with remote image interpretation for diabetic retinopathy screening: a comparison with ophthalmoscopy and standardized mydriatic color photography

PURPOSE: To evaluate single-field digital monochromatic nonmydriatic fundus photography as an adjunct in the screening of diabetic retinopathy. DESIGN: Prospective, comparative, observational case series. METHODS: Patients with type I and type II diabetes mellitus (n = 197) were sequentially evaluated by three different techniques: single-field digital monochromatic nonmydriatic photography; dilated ophthalmoscopy by an ophthalmologist; and seven Early Treatment Diabetic Retinopathy Study (ETDRS) standardized 35-mm color stereoscopic mydriatic images. The seven stereoscopic color photographs served as the reference standard and were compared with either ophthalmoscopy or a single digital photograph transmitted electronically to a reading site. Levels of agreement were determined by kappa analyses. The sensitivity and specificity of the three methods were compared based on a threshold for referral to further ophthalmologic evaluation (ETDRS level > or =35). RESULTS: There was highly significant agreement (kappa = 0.97, P =.0001) between the degree of retinopathy detected by a single nonmydriatic monochromatic digital photograph and that seen in seven standard 35-mm color stereoscopic mydriatic fields. The sensitivity of digital photography compared with color photography was 78%, with a specificity of 86%. Agreement was poor (kappa = 0.40, P =.0001) between mydriatic ophthalmoscopy and the seven-field standard 35-mm color photographs. Sensitivity of ophthalmoscopy compared with color photography was 34%, with a specificity of 100%. CONCLUSION: A single nonmydriatic monochromatic wide-field digital photograph of the disk and macula was more sensitive for diabetic retinopathy screening than mydriatic ophthalmoscopy, the currently accepted screening method. When adjudicated by standard seven-field color photographs, the higher sensitivity of digital photography primarily reflected the reduced sensitivity of ophthalmoscopy in detecting early retinopathy.     

Non-mydriatic fundus photography: A viable alternative to fundoscopy for identification of diabetic retinopathy in an Aboriginal population in rural Western Australia?

Purpose: To evaluate the Canon CR5-45NM non-mydriatic fundus camera (Canon, Kanagawa, Japan) for identifying retinopathy and the need for laser treatment in a population of Aboriginal patients with diabetes mellitus in rural Western Australia.
Methods: Diabetic Aboriginal patients were photographed through undilated pupils using a Canon CR5-45NM nonmydriatic fundus camera, after which ophthalmoscopy was performed using indirect ophthalmoscopy through dilated pupils. The examining ophthalmologist recorded the presence of retinopathy and the need for laser treatment. A proportion of patients were rephotographed through dilated pupils. Photographs were reviewed by a second ophthalmologist who evaluated the quality of the image, the presence of retinopathy and the need for laser treatment. Results of fundus photographs and ophthalmoscopy were compared.
Results: Three hundred and twenty-eight eyes in 164 Aboriginal patients were examined. The mean patient age was 48.2 years (range 16–81 years) and the mean duration of diabetes was 7.5 years (range 1–35 years). Seventy-four eyes (22.6%) were diagnosed with retinopathy using combined examination techniques, 44 (59.5%) of which were identified by ophthalmoscopy and 55 (74.3%) by photography. Thirty-five eyes were deemed to need treatment, 18 (51.4%) of which were identified by ophthalmoscopy and 30 (85.7%) by photography. Kappa coefficient measurement for agreement for presence of retinopathy and need for referral was 0.41 and 0.53, respectively. Photograph quality was significantly improved following pupil dilation.
Conclusions: The Canon CR5-45NM non-mydriatic fundus camera was relatively good at identifying diabetic retinopathy and could usefully be applied within a screening programme for treatable disease within this population.     

Screening for diabetic retinopathy by ophthalmologists and endocrinologists with pupillary dilation and a nonmydriatic digital camera

PURPOSE: To assess the effects of pupillary dilation on image quality and certitude of screening diabetic retinopathy by trained endocrinologists using a digital nonmydriatic camera. DESIGN: Prospective, comparative, observational case series. METHODS: One hundred fifty patients with diabetes attending a hospital-based photographic screening clinic had five-field (45 degree) digital retinal imaging and mosaic construction, first through dark-adapted pupils, then after a single application of tropicamide 1%. The 600 sets of images (150 patients, 300 eyes, before and after dilation) were graded independently and in a blinded manner by two endocrinologists and two ophthalmologists, with the consensual opinion on dilated images of the latter serving as the gold standard. The criteria of evaluation were assessment of image quality and certitude of detecting and grading retinopathy. RESULTS: Of 300 eyes, pharmacological mydriasis improved image quality, with an increase in the number of eyes with five good images from seven to 160 and good-quality mosaics from 99 to 233. Dilation allowed better identification of maculopathy in the second eye because there was a decrease in ungradeable central images from 127 to 15 eyes. Dilation increased the number of eyes having retinopathy detected with certainty from 153 to 252 and graded with certainty from 173 to 277. No adverse effects were recorded. CONCLUSIONS: Single application of tropicamide 1% significantly improves image quality and certitude of screening diabetic retinopathy with nonmydriatic camera by endocrinologists.     

Diabetic retinopathy screening using digital non-mydriatic fundus photography and automated image analysis

PURPOSE: To investigate the use of automated image analysis for the detection of diabetic retinopathy (DR) in fundus photographs captured with and without pharmacological pupil dilation using a digital non-mydriatic camera. METHODS: A total of 83 patients (165 eyes) with type 1 or type 2 diabetes, representing the full spectrum of DR, were photographed with and without pharmacological pupil dilation using a digital non-mydriatic camera. Two sets of five overlapping, non-stereoscopic, 45-degree field images of each eye were obtained. All images were graded in a masked fashion by two readers according to ETDRS standards and disagreements were settled by an independent adjudicator. Automated detection of red lesions as well as image quality control was made: detection of a single red lesion or insufficient image quality was categorized as possible DR. RESULTS: At patient level, the automated red lesion detection and image quality control combined demonstrated a sensitivity of 89.9% and specificity of 85.7% in detecting DR when used on images captured without pupil dilation, and a sensitivity of 97.0% and specificity of 75.0% when used on images captured with pupil dilation. For moderate non-proliferative or more severe DR the sensitivity was 100% for images captured both with and without pupil dilation. CONCLUSION: Our results demonstrate that the described automated image analysis system, which detects the presence or absence of DR, can be used as a first-step screening tool in DR screening with considerable effectiveness.     

Teleophthalmology screening for diabetic retinopathy through mobile imaging units within Canada

Background: This study aimed to describe and measure the health results of a Category 3 teleophthalmology screening project for diabetic retinopathy (DR). Implemented through mobile screening imaging units located within pharmacies, the project had the goal of reaching unscreened diabetic patients in urban communities while lowering barriers to screening and saving medical resources.Methods: Image capture of both eyes of 3505 known diabetic individuals was performed in the provinces of Quebec, British Columbia, Alberta, Manitoba, and Saskatchewan. A photographer performed fundus imaging, and a nurse used mild pupil dilation only when necessary to secure image quality. Screening was provided free of cost in the context of DR health days for DR screening. Through teleophthalmology, ophthalmologists proceeded with data and image interpretation, and timely referral when indicated.Results: This project allowed the resumption of screening of over 38% of the cohort of known diabetics who reported never having undergone any eye examination with pupil dilation, and an additional 30% who reported not having been examined for over 2 years. All known diabetics were under the care of a general physician, and their mean diabetes duration, when known, was 8 years. DR pathology was found in 22.5% (20%–28%) of the cohort, 1.8% requiring urgent referral (within 30 days) as a result of the severity of the DR and 0.6% (0%–l.8%) requiring urgent referral for other reasons. An additional 8.7% (8.1%–19.5%) required ophthalmologic attention within 6 months because of DR and another 2.0% (0%–6.3%) between 6 months and I year. Incidental findings were found in 23%, the majority of which were related to cataract and dry macular degeneration. Urgent or significant incidental findings were found in 0.6% of the screened eyes. Pupil dilation with tropicamide 1% was deemed useful or necessary in 33.7% of the cohort. For 0.7% of the cohort, the images could not be interpreted because of poor image quality and for that reason had to be referred for a traditional dilated eye examination. Ophthalmologists were relieved of the examination of 85.6% of the screened diabetic individuals who benefited from screening without requiring a traditional ophthalmologic examination. On the other hand, ophthalmologists were required to provide urgent (within 30 days) services to 2% of the cohort, either because of threatening DR or because of incidental findings requiring rapid ophthalmologic attention.Interpretation: This screening strategy for DR through mobile teleophthalmology imaging units efficiently lowered barriers to screening and created new screening opportunities for a large number of known diabetic individuals who were lost to the traditional health system. It has the potential to provide better outreach to diabetic populations while identifying individuals truly in need of the services of an ophthalmologist; at the same time it maximizes the use of limited ophthalmologic resources while favouring multidisciplinary collaborations. The significant incidental findings associated with screening highlight the need for ophthalmologic competencies during DR screening within a teleophthalmology approach. Further involvement of government health authorities is pivotal in embracing the opportunities provided by emerging technologies such as teleophthalmology and translating them into better outreach services to diabetic populations and thus better visual health results.     

Evaluation of diabetic retinopathy screening using a non-mydriatic retinal digital camera in primary care settings in south Israel

To evaluate the effectiveness of the non-mydriatic digital camera for diabetic retinopathy (DR) screening. Secondary purposes of the study were to characterize diabetic patients being screened for the presence of DR and to calculate the sensitivity, specificity, and positive predictive value of the test. All 6,962 consecutive patients with type 2 diabetes undergoing non-mydriatic digital retinal photography between January 1, 2009 and June 30, 2010 in eight community health clinics in the south of the country were included. Comparison of a random sample of patients who underwent non-mydriatic retinal photography, and who were also examined by an ophthalmologist with pupil dilation was also performed. The average age of all patients was 64.2 years. A total of 5,960 cases (85.6 % of all photographs) were of adequate quality for the diagnosis. DR of any degree was found in 1,092 (18.3 %) patients. Normal fundus pictures were found in 49.4 % of patients. In 32.2 % of cases, non-DR pathologies were found. Among cases in which DR was found, 73.3 % (801 cases) had mild non-proliferative retinopathy (NPDR), 7.1 % (77 cases) had moderate NPDR, 6.8 % (74 cases) had proliferative retinopathy, and 12.8 % (140 cases) had diabetic macular edema. Older patients had more chance of having poor quality pictures (p < 0.001 between patients older and younger than 70 years). When non-mydriatic fundus photography was compared with dilated fundus examination by an ophthalmologist, sensitivity of 99.3 %, specificity of 88.3 %, and positive predictive value of 85.3 % were found. Non-mydriatic digital retinal photography is an efficient method for DR screening. The test has high sensitivity and specificity. The test, as performed in community health centers in the south of the country, contributed to the early diagnosis of >1,000 cases of DR. Many patients can be followed up in a fast and efficient way, although the test cannot replace a complete eye examination after pupil dilation mainly in older people. Other non-DR sight-threatening ocular pathologies can be also detected.     

上海市北新泾社区糖尿病视网膜病变远程筛查系统的应用研究

目的 探讨社区糖尿病视网膜病变(DR)远程筛查系统的应用效果.方法 横断面研究.以免散瞳数码眼底照相机和计算机网络技术为基础,构建社区DR远程筛查系统.采用随机数字表法抽取109例已进入筛查系统的糖尿病居民进行系统评价.评价内容:1)经过培训的视力检查员和眼科医师对同一患者双眼远视力检查结果的一致性,采用配对t检验进行分析;不同眼病的分析人员分别按该系统中免散瞳眼底照相的读片法和散瞳后应用检眼镜、裂隙灯显微镜联合90D非接触镜检查法(传统检查法),对同一患者双眼DR诊断和分级结果的一致性进行评价,采用kappa值和组内相关系数进行分析;(2)对眼底照相获取的图像进行不同比例的压缩,通过该系统网络传输后,采用组内相关系数分析压缩后的图像质量,获得合适的压缩比例;(3)计算筛查系统运行所需的时间,并与传统检杳法进行比较.结果 109例(218只眼)受检者中,由眼科医师检查获取的视力分布情况:力<0.05者13只眼,视力0.05～0.3者61只眼,视力≥0.3者144只眼,与其他检查人员的视力检查结果比较,差异无统计学意义(t=-0.572,P=0.568).采用传统检杳法与眼底照相法诊断为DR的眼数相同,均为52只眼,两者间比较的kappa值为0.885,95%可信区间为0.807～0.963;DR不同分级诊断的一致性:内相关系数为0.91,95%可信区间为0.85～0.94,表明两者的一致性好.将眼底照相获取的图像,以最大限度压缩至原始图像的15%(526×350像素)时,图像清晰度仍不受影响.每位受检者实时远程筛查所需的时间为5～7 min,略少于传统检查法所需时间.结论 社区DR远程筛查系统可满足DR患者筛查的需求.     

Fundus evaluation in COVID-19 positives with non-severe disease

Purpose:The aim of this work was to study and document retinal changes in coronavirus disease-2019 (COVID-19) positive patients with nonsevere disease using a nonmydriatic handheld fundus camera.Methods:A cross-sectional observational study was conducted on patients affected by COVID-19 who were admitted at our center. Our study included patients with no, mild, and moderate symptoms (nonsevere cases). Intensive care unit (ICU)-admitted patients were excluded considering the difficulty in procuring the fundus image by the handheld camera due to patients positioning. Patients with systemic conditions (diabetes, hypertension, and severe anemia) known to cause retinopathy were also excluded. Bedside anterior segment examination, fundus examination using indirect ophthalmoscopy and fundus imaging of each patient using a nonmydriatic handheld fundus camera was done by a trained ophthalmologist posted for COVID duty.Results:In a cohort of 138 patients, 94 (68.1%) were men and 44 (31.9%) were women. A total of 276 eyes were evaluated. The mean age of the patients was 38.51 ± 14.4 years. Anterior segment evaluation showed no abnormality in any of the eyes. On fundus screening using nonmydriatic handheld camera, a single streak of superficial retinal hemorrhage was noted at the posterior pole of the fundus in the left eye of one patient (0.72%), which was away from fovea. Laboratory tests revealed low hemoglobin (between 10 and 10.9 g/dL falling under mild Anemia) in 12 patients, elevated total leucocyte count in 6 patients, raised LDH in majority of patients (323 ± 101 Units/L) and elevated CRP (14.6 ± 30.99 mg/L). Rest of the lab parameters were within the normal range.Conclusion:In our study, COVID patients with mild-to-moderate symptoms did not show any inflammatory/infective or vaso-occlusive lesions in the retina attributable to COVID-19 infection, except one patient who had a single streak hemorrhage in the macula away from fovea, probably incidental.     

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

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

免散瞳眼底数码照相机筛查白内障需手术者的方法评估

目的通过免散瞳眼底数码照相方法诊断白内障并筛出白内障需手术者,探讨用该方法筛查白内障的可行性。设计前瞻性病例系列。研究对象2009年2月至8月同仁医院白内障中心就诊的白内障患者92例165眼。方法所有病例均检查裸眼视力及矫正视力,经裂隙灯显微镜检查并进行白内障分类分级。使用免散瞳眼底数码照相机进行小瞳孔眼底数码照相检查,根据眼底照片的模糊程度作出分级诊断。比较免散瞳眼底照相的诊断结果与裂隙灯检查结果的一致性,两种手术诊断标准所得筛查结果进行Kappa检验。主要指标灵敏度、特异度、约登（Youden）指数、阳性预测值、阴性预测值。结果免散瞳眼底照相与裂隙灯检查结果呈高度一致性。以裂隙灯显微镜检查为金标准,各级白内障中2级以上者免散瞳眼底照相诊断的灵敏度均在89％以上。免散瞳艰底照相筛查白内障需手术者的Kappa值均达0．70以上。皮质性、核性和囊下性的阳性预测值分别为100％、84．2％和76．2％,阴性预测值分别为82．4％、93．3％和91．9％。结论用免散瞳眼底照相方法筛查明显影响视力的中、重度白内障是可行的。可以用免散瞳眼底照相方法替代裂隙灯显微镜检查法筛查白内障需手术者。     

Is screening with digital imaging using one retinal view adequate?

PURPOSE: To compare the detection of diabetic retinopathy from digital images with slit-lamp biomicroscopy, and to determine whether British Diabetic Association (BDA) screening criteria are attained (>80% sensitivity, >95% specificity, &<5% technical failure). METHODS: Diabetics referred for screening were studied in a prospective fashion. A single 45 degrees fundus image was obtained using the nonmydriatic digital camera. Each patient subsequently underwent slit-lamp biomicroscopy and diabetic retinopathy grading by a consultant ophthalmologist. Diabetic retinopathy and maculopathy was graded according to the Early Treatment of Diabetic Retinopathy Study. RESULTS: A total of 145 patients (288 eyes) were identified for screening. Of these, 26% of eyes had diabetic retinopathy, and eight eyes (3%) had sight-threatening diabetic retinopathy requiring treatment. The sensitivity for detection of any diabetic retinopathy was 38% and the specificity 95%. There was a 4% technical failure rate. There were 42/288 false negatives and 10/288 false positives. Of the 42 false negatives, 18 represented diabetic maculopathy, 20 represented peripheral diabetic retinopathy and four eyes had both macular and peripheral changes. Three eyes in the false-negative group (1% of total eyes) had sight-threatening retinopathy. There was good concordance between the two consultants (79% agreement on slit-lamp biomicroscopy and 84% on digital image interpretation). CONCLUSION: The specificity value and technical failure rate compare favourably with BDA guidelines. The low sensitivity for detection of any retinopathy reflects failure to detect minimal maculopathy and retinopathy outside the 45 degrees image. This could be improved by an additional nasal image and careful evaluation of macular images with a low threshold for slit-lamp biomicroscopy if image quality is poor.     

Fundusscreening durch Assistenzpersonal

Ocular fundus photography allows detection of both ocular and systemic diseases. This study investigated the efficacy of a broad screening in a department of internal medicine using nonmydriatic digital fundus photography. For 8 weeks a medical technician was trained in using the camera as well as interpreting the photographs. The medical technician and an ophthalmologist evaluated the fundus photographs separately by using a self-developed questionnaire. The fundus camera was user-friendly and after several weeks of adjustment and practical application the medical technician was able to detect the majority of pathological fundus photographs. Out of 218 patients examined 148 (68%) were identified as pathological by the medical technician and 163 (75%) by the ophthalmologist (p?=?0.0003). The medical technician missed 15 (7%) patients. Furthermore the diagnoses made by the medical technician were faulty. In summary an ophthalmological screening by a medical technician is feasible but the diagnosis still remains the responsibility of ophthalmologists. Such a compromise could facilitate the examination of a large number of patients and disclose previously unrecognized diseases.     

A screening approach to the surveillance of patients with diabetes for the presence of vision-threatening retinopathy

OBJECTIVE: To provide scientifically based screening rules for the primary care setting designed to identify, through evaluation of a prescribed and limited portion of the posterior fundus, those patients with diabetes who have retinopathy severe enough to need referral to eye care specialists. DESIGN: Retrospective analysis of the Early Treatment Diabetic Retinopathy Study (ETDRS) photographic data base. PARTICIPANTS: The fundus photographic grading data from 3711 patients with diabetes enrolled in the ETDRS. METHODS: Multivariate regression techniques were used to identify retinopathy lesions in photographic fields 1, 2, 3, or a combination thereof that predict proliferative diabetic retinopathy (PDR) or clinically significant macular edema (CSME) within the seven standard fields. These were used to construct a family of screening rules with optimal combined sensitivity and specificity on which to base referrals to eye care specialists. MAIN OUTCOME MEASURES: Presence of moderate to severe nonproliferative diabetic retinopathy (NPDR), PDR, or CSME in graded fundus photographs. RESULTS: Hemorrhages and microaneurysms (h/ma) temporal to the macula (photographic field 3), as severe as or more severe than ETDRS standard photograph 1 (h/ma 3 > or = 3), identified 87% to 89% of eyes with PDR and 92% to 93% of eyes with moderately severe to severe NPDR, which are at high risk for developing PDR. Extrapolating the results using retinopathy prevalence data from epidemiologic studies for the general older onset diabetic population, the calculated sensitivity for detecting PDR on a single examination is 87%, the specificity 80%; for moderate NPDR or worse, the sensitivity is 81 %, specificity 93%. Applying the presence of h/ma 3 > or = 3 as a screening rule to the older onset population, 26.5% of patients would be referred and 73.5% would not be referred. Any hard exudate within one disc diameter of the macular center detects CSME with sensitivity 94%, specificity 54%. Hard exudate of moderate or worse severity anywhere in the macular region (field 2) predicts CSME with sensitivity 89%, specificity 58%. CONCLUSIONS: Screening protocols based on assessing retinopathy lesion severity in the posterior fundus have the potential to identify most diabetic patients with vision-threatening retinopathy. If the protocols can be implemented effectively in a primary care setting, patients requiring referral for specialty care could be reliably identified, and the total number of patients needing specialty referral could be substantially reduced from current guidelines.     

Compliance with recommendations from a screening programme for diabetic retinopathy.

METHODS: General practitioner compliance with recommendations for patient follow-up after participation in a screening programme for diabetic retinopathy was assessed. Six months after screening with non-mydriatic retinal photography in four areas of Victoria, the genera practitioner of each participant was surveyed if the participant reported no examination for diabetic retinopathy in the past 2 years and if the results of the screening indicated the need for further assessment. RESULTS: Overall, 208 of 253 (82%) completed questionnaires were analysed. A total of 123 (59%) patients were referred by their doctors for further assessment and 97 (79%) of those referred were reported to have complied with the referral. Of the 85 (41%) patients who were not referred for further assessment, 31 (36%) were reported by their doctors to be already under regular review by an ophthalmologist. CONCLUSIONS: Compliance with genera practitioner referrals suggests that this screening programme was effective and a useful means by which to remind general practitioners of the importance of regular eye examinations for people with diabetes.     

Screening for diabetic retinopathy by one-field, non-mydriatic, 45 degrees digital photography is inadequate

PURPOSE: To evaluate the sensitivity and specificity of one-field, non-mydriatic, 45 degrees digital photography for screening for diabetic retinopathy compared to indirect ophthalmoscopy using a slit-lamp, the reference standard. METHODS: A total of 100 consecutive diabetic patients (200 eyes) who underwent digital fundus photography and ocular examinations from June 2002 to November 2002 were included in this retrospective study. The patients, recruited from a hospital-based, retina referral practice, underwent 45 degrees, non-mydriatic, digital fundus photography using a non-mydriatic fundus camera. One image was obtained focusing the mid fundus between the optic disc and the macula. The fundus images were printed and graded by endocrinologists and a retinal specialist separately. The patients also underwent complete standard ocular examinations as the reference method for determining diabetic retinopathy, including dilation of their pupils and slit-lamp biomicroscopy done by ophthalmologists. The sensitivity and specificity of the digital photographic method were calculated by comparison to the reference method. RESULTS: The sensitivity and specificity of the retinal specialist's diabetic retinopathy grades were 53.8 and 89.0%, respectively. The sensitivity and specificity of the endocrinologists' grades were 45 and 75.3%, respectively. The false negative rates were 22 and 21.5% for endocrinologists and the retinal specialist, respectively. CONCLUSIONS: Screening for diabetic retinopathy using one-field, non-mydriatic, 45 degrees digital photography is inadequate.     

学龄前儿童假性近视眼292例分析

目的了解学龄前儿童假性近视眼的性质与特点。方法视光门诊中"近视眼"(远视力<1.0、近视力≥1.0、原瞳验光为近视的)4~6岁学龄前儿童292名515眼。除眼科常规检查外,均用1%阿托品眼膏散瞳,每晚涂眼1次,共7天。1周后由专职人员验光。结果292人515眼中,远视478眼,占92.81%,正视11眼(2.14%),混合散光26眼(5.05%)。结论学龄前儿童假性近视眼的屈光基础为远视眼,为调节导致。学龄前儿童应用阿托品散瞳验光。     

Clinical evaluation of patients with diabetic retinopathy: accuracy of the Inoveon diabetic retinopathy-3DT system

PURPOSE: This study analyzed the accuracy of the Inoveon Diabetic Retinopathy (DR-3DT) system (Inoveon Corp., Oklahoma City, OK), a scalable evaluation method for the management of diabetic retinopathy using high-quality digital retinal imaging. DESIGN: An independent, masked, cross-sectional, clinical validation study. PARTICIPANTS: Two hundred ninety adult patients with diabetes from the Chickasaw Nation's Carl Albert Indian Health Facility in Ada, Oklahoma. METHODS: All participants underwent DRS7 imaging using a Zeiss FF450 fundus camera with images recorded on 35-mm film and a Kodak DCS520 digital camera back. Masked double grading with independent third reader adjudication yielded an Early Treatment Diabetic Retinopathy Study (ETDRS) Final Retinopathy Severity Scale Level (ETDRS Level) and macular edema stage for each eye. The presence of greater-than-or-equal ETDRS Level 53, questionable or definite clinically significant macular edema in either eye, or ungradeable images was defined as a threshold event requiring referral. MAIN OUTCOME MEASURES: Accuracy (sensitivity, specificity, predictive values) of the digital system relative to the film "gold standard" on the threshold referral criteria per patient. RESULTS: All patients with gradeable 35-mm slides from at least one eye were included in this per patient analysis (n = 290). The prevalence of threshold events was 19.3%. The sensitivity of the digital system in detecting threshold events was 98.2% (95% confidence interval [CI], 90.5%-100.0%) and specificity 89.7% (95% CI, 85.1%-93.3%). The positive predictive value was 69.5% and negative predictive value 99.5% for this sample. CONCLUSIONS: When compared with the "gold standard," Inoveon's DR-3DT system provides highly accurate diabetic retinopathy referral decisions. Given their inherent advantages, high-quality digital imaging systems could replace the film "gold standard" as the basis for scalable, accessible, diabetic retinopathy evaluation.