Widefield imaging with Clarus fundus camera vs slit lamp fundus examination in assessing patients referred from the National Health Service diabetic retinopathy screening programme

Abstract

Objectives To compare diabetic retinopathy (DR) grading and management plan between virtual review using widefield Clarus imaging and macular optical coherence tomography (OCT) versus slit lamp clinical examination and macular OCT. Method New referrals over 3 months from the National Diabetic Eye Screening programme (DESP) were screened. Patients who had both Clarus widefield imaging and macular OCT were included. All patients underwent slit lamp examination in clinic. Data obtained from electronic patient records included referral reason, DR grading and management plan. Two graders retrospectively reviewed imaging and formulated a management plan blinded to results from patients' clinic visit. Results from virtual examination were compared with those from slit lamp examination. Results One-hundred and two eyes of 51 patients were assessed. 11 fundus photos from 7 patients and 15 fundus photos from 10 patients were deemed inadequate by grader G1 and G2, respectively. Eighteen (35%) patients and 11 (22%) patients from virtual assessment by G1 and G2, respectively were found to need a face a face appointment to aid diagnosis. Compared to slit lamp examination, 15% and 7.5% of patients from G1 and G2's virtual assessment respectively had different proposed management plan. Agreement of DR grading between both virtual graders and slit lamp examination was fair (Kappa's coefficient = 0.56). One case of slit lamp noted retinal neovascularization, which was graded as background retinopathy by DESP was also graded as such on virtual assessment. Conclusion Widefield Clarus and OCT imaging allowed two-thirds of DESP referrals to be safely managed virtually.

Ultra-wide-field fundus photography compared to ophthalmoscopy in diagnosing and classifying major retinal diseases

“…Moreover, these last reports used Optos® system 7,21 , whose limitations, mainly concerning true color, have already been reported 4 . On the other hand, our results are consistent with some recent studies 4,5,8,16,19,23 , even if these studies were also performed on small populations, for selected diagnosis (diabetic retinopathy 4,5 , peripheral lesions 8 , rhegmatogenous retinal detachment 19 , ocular Toxoplasmosis 23 , sickle cell retinopathy 16 ). In accordance with another analysis 14 , the missing diagnosis we reported were very limited in number and due to lesions located in the extreme upper temporal periphery , and statistically no significant.…”

“…Although indirect ophthalmoscopy, particularly associated to scleral depression, and posterior biomicroscopy still remain the gold standard for fundus examination 19 , over the last ten years the use of fundus photography system has extensively increased 11,12,20 , as an adjunct to clinical evaluation 7,21,22 or as a screening tool for many retinal diseases, in particular diabetic retinopathy [4][5][6]10 , peripheral retinal lesions 8,9 and other retinal disorders 16,23,24 , also by means of deep learning technologies 3,6,25,26 . This is due to the progressive improvement of retinal fundus cameras, involving both the extent of retinal field evaluated and the quality of images: from the earliest cameras www.nature.com/scientificreports/ encompassing a retinal field of 20-30° in a single image 12 , we have now systems capable of acquiring real color fundus images covering up to 200° of retinal field with a pixel definition of 6604 × 4274 (Clarus™), or providing a two-tone fundus image of 200° of field with a 3900 × 3072 pixel definition (Optos®) 4,12,14 .…”

“…Recent studies evaluated UWF imaging for individual disorders, most of which performed on diabetic retinopathy, peripheral retinal lesions or other retinal disorders. Some reports have shown that UWF fundus imaging is an effective useful tool for the assessment of diabetic retinopathy 4,5,12 , focusing on the higher accuracy of Clarus™ in detecting microaneurysm and retinal hemorrhages: by providing real color images and reducing lids and lashes artifacts, it allows a slightly more precise staging of diabetic retinopathy and maculopathy than Optos® camera 4 . Conversely, studies assessing the effectiveness of UWF imaging in detecting peripheral retinal lesions, such as retinal degenerations, retinal breaks, rhegmatogenous retinal detachment, have been conducted primarily with Optos®: despite considering UWF imaging a useful adjunct to medical evaluation, some authors do not agree it may represent substitute of clinical ophthalmoscopy due to the possible missing of some peripheral retinal lesions 7,21 .…”

Imaging Modalities Employed in Diabetic Retinopathy Screening: A Review and Meta-Analysis

“…The recently released Clarus 500 and Clarus 700 (Carl Zeiss Meditec AG, Jena, Germany) capture "true-color" images that may potentially enable more accurate identification of DR lesions, although this has yet to be demonstrated in clinical trials [130]. Within the currently published studies, images obtained with Clarus were consistent with current UWF-SLO devices in assessing the severity of DR, with no statistically significant difference in patient or technician preference, and image acquisition time [131][132][133]. The Eidon confocal scanner (Centervue, Padova, Italy) couples confocal imaging with natural white-light illumination to obtain a true-colour image using a white LED (440-650 nm).…”

Digital Advancements in Retinal Models of Care in the Post–COVID-19 Lockdown Era

“…One of the major limitations of telemedicine in retina is the need to obtain anatomical evaluation of the macular and retina to make treatment decisions. Prepandemic, various institutions have already developed imaging-based “virtual” clinics, with asynchronous review of imaging results and telemedicine-based communication of findings to patients 7–9. These virtual imaging clinics often deploy optical coherence tomography (OCT) with standard or ultra-widefield fundus photography to provide the imaging input required to manage diseases from diabetic retinopathy and macular edema to age-related macular degeneration (AMD).…”