Evaluation of Nonmydriatic Hand-held Optic Disc Photography Grading in the Philadelphia Glaucoma Detection and Treatment Project

Mobile Diagnostic Clinics

This article reviews the revolutionary impact of emerging technologies and artificial intelligence (AI) in reshaping modern healthcare systems, with a particular focus on the implementation of mobile diagnostic clinics. It presents an insightful analysis of the current healthcare challenges, including the shortage of healthcare workers, financial constraints, and the limitations of traditional clinics in continual patient monitoring. The concept of "Mobile Diagnostic Clinics" is introduced as a transformative approach where healthcare delivery is made accessible through the incorporation of advanced technologies. This approach is a response to the impending shortfall of medical professionals and the financial and operational burdens conventional clinics face. The proposed mobile diagnostic clinics utilize digital health tools and AI to provide a wide range of services, from everyday screenings to diagnosis and continual monitoring, facilitating remote and personalized care. The article delves into the potential of nanotechnology in diagnostics, AI's role in enhancing predictive analytics, diagnostic accuracy, and the customization of care. Furthermore, the article discusses the importance of continual, noninvasive monitoring technologies for early disease detection and the role of clinical decision support systems (CDSSs) in personalizing treatment guidance. It also addresses the challenges and ethical concerns of implementing these advanced technologies, including data privacy, integration with existing healthcare infrastructure, and the need for transparent and bias-free AI systems.

Comparison of Three Handheld Fundus Cameras for Assessment of the Vertical Cup-To-Disk Ratio

Purpose To compare the quality of optic nerve photographs from three different handheld fundus cameras and to assess the reproducibility and agreement of vertical cup-to-disk ratio (VCDR) measurements from each camera. Methods Adult patients from a comprehensive ophthalmology clinic and an intravitreous injection clinic in northern Thailand were recruited for this cross-sectional study. Each participant had optic nerve photography performed with each of 3 handheld cameras: the Volk iNview, Volk Pictor Plus, and Peek Retina. Images were graded for VCDR in a masked fashion by two photo-graders and images with > 0.2 discrepancy in VCDR were assessed by a third photo-grader. Results A total of 355 eyes underwent imaging with three different handheld fundus cameras. Optic nerve images were judged ungradable in 130 (37%) eyes imaged with Peek Retina, compared to 36 (10%) and 55 (15%) eyes imaged with the iNview and Pictor Plus, respectively. For 193 eyes with gradable images from all 3 cameras, inter-rater reliability for VCDR measurements was poor or moderate for each of the cameras, with intraclass correlation coefficients ranging from 0.41 to 0.52. A VCDR ≥ 0.6 was found in 6 eyes on iNview images, 9 eyes on Pictor Plus images, and 3 eyes on Peek images, with poor agreement between cameras (e.g., no eyes graded as VCDR ≥ 0.6 on images from both the iNview and Pictor Plus). Conclusions Inter-rater reliability of VCDR grades from 3 handheld cameras was poor. Cameras did not agree on which eyes had large VCDRs.

Feasibility and clinical utility of handheld fundus cameras for retinal imaging

BACKGROUND/OBJECTIVES

Handheld fundus cameras are portable and cheaper alternatives to table-top counterparts. To date there have been no studies comparing feasibility and clinical utility of handheld fundus cameras to table-top devices. We compare the feasibility and clinical utility of four handheld fundus cameras/retinal imaging devices (Remidio NMFOP, Volk Pictor Plus, Volk iNview, oDocs visoScope) to a table-top camera (Zeiss Visucam^NM/FA).

SUBJECTS/METHODS

Healthy participants (n = 10, mean age ± SD = 21.0 ± 0.9 years) underwent fundus photography with five devices to assess success/failure rates of image acquisition. Participants with optic disc abnormalities (n = 8, mean age ± SD = 26.8 ± 15.9) and macular abnormalities (n = 10, mean age ± SD = 71.6 ± 15.4) underwent imaging with the top three scoring fundus cameras. Images were randomised and subsequently validated by ophthalmologists masked to the diagnoses and devices used.

RESULTS

Image acquisition success rates (100%) were achieved in non-mydriatic and mydriatic settings for Zeiss, Remidio and Pictor, compared with lower success rates for iNview and oDocs. Image quality and gradeability were significantly higher for Zeiss, Remidio and Pictor (p < 0.0001) compared to iNview and oDocs. For cup:disc ratio estimates, similar levels of bias were seen for Zeiss (-0.09 ± SD:0.15), Remidio (-0.07 ± SD:0.14) and Pictor (-0.05 ± SD:0.16). Diagnostic sensitivities were highest for Zeiss (84.9%; 95% CI, 78.2-91.5%) followed by Pictor (78.1%; 95% CI, 66.6-89.5%) and Remidio (77.5%; 95% CI, 65.9-89.0%).

CONCLUSIONS

Remidio and Pictor achieve comparable results to the Zeiss table-top camera. Both devices achieved similar scores in feasibility, image quality, image gradeability and diagnostic sensitivity. This suggests that these devices potentially offer a more cost-effective alternative in certain clinical scenarios.

The effect of photographic light brightness on cup to disc ratio grading

BACKGROUND

Digital optic disc photographs are integral to remote telehealth ophthalmology, yet no quality control standards exist for the brightness setting of the images. This study evaluated the relationship between brightness setting and cup/disc ratio (c/d) grading among glaucoma specialists.

METHODS

Optic disc photographs obtained during routine examinations under anesthesia were collected to construct an image library. For each optic disc, photographs were obtained at 3 light intensity settings: dark, medium, and bright. From the image library, photograph triads (dark, medium and bright) of 50 eyes (50 patients) were used to construct the study set. Nine glaucoma specialists evaluated the c/d of the study set photographs in randomized order. The relationships between the brightness levels and the c/d grading as well as graders' years in practice and variability were evaluated.

RESULTS

The c/d were graded as significantly larger in bright photographs when compared to photographs taken at the medium light intensity (0.53 vs 0.48, P < 0.001) as well as those taken at the dark setting (0.47, P < 0.001). In addition, no relationship was found between ophthalmologists' years in practice and the variability of their c/d grading (P = 0.76).

CONCLUSION

Image brightness affects c/d grading of nonstereoscopic disc photographs. The brighter intensity is associated with larger c/d grading. Photograph brightness may be an important factor to consider when evaluating digital disc photographs.

Spotlight on the Disc-Damage Likelihood Scale (DDLS)

The disc damage likelihood scale (DDLS) is a tool for classifying glaucomatous structural changes to the optic disc based on the radial width of the neuroretinal rim at its thinnest location, or if no rim is present, the extent of absence of the rim. Unlike cup disc ratio (CDR), the DDLS also considers disc size. Twenty years after its first description, the aim of this review was to critically appraise evidence for the DDLS and evaluate its role in current practice. A literature search by two independent authors identified 33 relevant articles for inclusion. Five studies evaluated reproducibility, 5 diagnostic performance, and 2 studies examined ability to detect progression. Eleven studies evaluated correlation between DDLS and other markers of glaucoma. Despite the widespread availability of imaging devices such as optical coherence tomography (OCT), clinical examination of the optic disc remains an essential component of glaucoma diagnosis and monitoring. The DDLS provides a reliable method for semi-quantitative clinical grading of the optic disc in glaucoma, with higher reproducibility than methods such as CDR.

Philadelphia glaucoma detection and treatment project: ocular outcomes and adherence to follow-up at a single health centre

OBJECTIVES

To determine ocular outcomes and factors associated with adherence to ophthalmic follow-up in a medically underserved population at a single health centre in Philadelphia.

DESIGN

Retrospective chart review.

PARTICIPANTS

Patients from a community glaucoma screening program.

METHODS

Chart review was conducted for participants who received a complete eye examination at the Philadelphia District Health Center 5 between January 1, 2012 and May 31, 2014 within the Philadelphia Glaucoma Detection and Treatment Project. Multivariate logistic regression was used to determine factors related to ophthalmic follow-up adherence.

RESULTS

A total of 249 participants completed an eye examination (mean age = 57.7 ± 6.9 years). Most were African American (n = 220; 88.4%); female (n = 129; 51.8%). Forty-seven participants (18.9%) received glaucoma-related diagnoses, 20 (8.0%) were prescribed ocular medication, and 26 (10.4%) underwent laser therapy. Ninety (36.1%) attended their recommended follow-up eye examination at the health centre. Glaucoma-related diagnosis (p ≤ 0.001), recommendation of a 4- to 6-week follow-up period (p < 0.001), prescribed eye drops (p < 0.001), or received laser therapy (p = 0.047) were factors most predictive of ophthalmic follow-up adherence.

CONCLUSIONS

The collaborative effort of eye care providers and health centres offers an important opportunity to detect, treat, and manage glaucoma and other ocular pathology in medically underserved communities. Having a glaucoma-related diagnosis, initiating treatment, and scheduling regular follow-up visits are the most important factors influencing adherence to follow-up eye appointments.

Glaucoma Screening in Nepal: Cup-to-Disc Estimate With Standard Mydriatic Fundus Camera Compared to Portable Nonmydriatic Camera

PURPOSE

To compare cup-to-disc ratio (CDR) measurements from images taken with a portable, 45-degree nonmydriatic fundus camera to images from a traditional tabletop mydriatic fundus camera.

DESIGN

Prospective, cross-sectional, comparative instrument validation study.

METHODS

Setting: Clinic-based.

STUDY POPULATION

A total of 422 eyes of 211 subjects were recruited from the Tilganga Institute of Ophthalmology (Kathmandu, Nepal). Two masked readers measured CDR and noted possible evidence of glaucoma (CDR ≥ 0.7 or the presence of a notch or disc hemorrhage) from fundus photographs taken with a nonmydriatic portable camera and a mydriatic standard camera. Each image was graded twice.

MAIN OUTCOME MEASURES

Effect of camera modality on CDR measurement; inter- and intraobserver agreement for each camera for the diagnosis of glaucoma.

RESULTS

A total of 196 eyes (46.5%) were diagnosed with glaucoma by chart review; 41.2%-59.0% of eyes were remotely diagnosed with glaucoma over grader, repeat measurement, and camera modality. There was no significant difference in CDR measurement between cameras after adjusting for grader and measurement order (estimate = 0.004, 95% confidence interval [CI], 0.003-0.011, P = .24). There was moderate interobserver reliability for the diagnosis of glaucoma (Pictor: κ = 0.54, CI, 0.46-0.61; Topcon: κ = 0.63, CI, 0.55-0.70) and moderate intraobserver agreement upon repeat grading (Pictor: κ = 0.63 and 0.64, for graders 1 and 2, respectively; Topcon: κ = 0.72 and 0.80, for graders 1 and 2, respectively).

CONCLUSIONS

A portable, nonmydriatic, fundus camera can facilitate remote evaluation of disc images on par with standard mydriatic fundus photography.

Philadelphia Telemedicine Glaucoma Detection and Follow-up Study: Methods and Screening Results

PURPOSE

To describe methodology and screening results from the Philadelphia Telemedicine Glaucoma Detection and Follow-up Study.

DESIGN

Screening program results for a prospective randomized clinical trial.

METHODS

Individuals were recruited who were African-American, Hispanic/Latino, or Asian over age 40 years; white individuals over age 65 years; and any ethnicity over age 40 years with a family history of glaucoma or diabetes. Primary care offices and Federally Qualified Health Centers were used for telemedicine (Visit 1). Two posterior fundus photographs and 1 anterior segment photograph were captured per eye in each participant, using a nonmydriatic, autofocus, hand-held fundus camera (Volk Optical, Mentor, Ohio, USA). Medical and ocular history, family history of glaucoma, visual acuity, and intraocular pressure measurements using the ICare rebound tonometer (ICare, Helsinki, Finland) were obtained. Images were read remotely by a trained retina reader and a glaucoma specialist.

RESULTS

From April 1, 2015, to February 6, 2017, 906 individuals consented and attended Visit 1. Of these, 553 participants were female (61.0%) and 550 were African-American (60.7%), with a mean age of 58.7 years. A total of 532 (58.7%) participants had diabetes, and 616 (68%) had a history of hypertension. During Visit 1, 356 (39.3%) participants were graded with a normal image. Using image data from the worse eye, 333 (36.8%) were abnormal and 155 (17.1%) were unreadable. A total of 258 (28.5%) had a suspicious nerve, 62 (6.8%) had ocular hypertension, 102 (11.3%) had diabetic retinopathy, and 68 (7.5%) had other retinal abnormalities.

CONCLUSION

An integrated telemedicine screening intervention in primary care offices and Federally Qualified Health Centers detected high rate of suspicious optic nerves, ocular hypertension, and retinal pathology.

Predictors of Photographic Quality with a Handheld Nonmydriatic Fundus Camera Used for Screening of Vision-Threatening Diabetic Retinopathy

PURPOSE

To analyze predictors of image quality for a handheld nonmydriatic fundus camera used for screening of vision-threatening diabetic retinopathy.

METHODS

An ophthalmic photographer at an Aravind Eye Hospital obtained nonmydriatic and mydriatic fundus images from 3 fields in 275 eyes of 155 participants over 13 months using a Smartscope camera (Optomed, Oulu, Finland) and a Topcon tabletop fundus camera (Topcon, Tokyo, Japan). Two fellowship-trained retina specialists graded the images. Repeated-measures logistic regression assessed predictors of the main outcome measure: gradability of the fundus images.

RESULTS

Of 2,475 images, 76.2% of the Smartscope nonmydriatic images, 90.1% of the Smartscope mydriatic images, and 92.0% of the Topcon mydriatic images were gradable. Eyes with vitreous hemorrhage (OR = 0.24, p < 0.0001) or advanced cataract (OR = 0.08, p < 0.0001) had decreased odds of image gradability. Excluding eyes with cataract or vitreous hemorrhage, nonmydriatic macular image gradability improved from 68.4% in the first set of 55 eyes to 94.6% in the final set of 55 eyes.

CONCLUSION

With sufficient training, paraprofessional health care staff can obtain high-quality images with a portable nonmydriatic fundus camera, particularly in patients with clear lenses and clear ocular media.

The Philadelphia Glaucoma Detection and Treatment Project: Detection Rates and Initial Management

PURPOSE

To evaluate the detection rates of glaucoma-related diagnoses and the initial treatments received in the Philadelphia Glaucoma Detection and Treatment Project, a community-based initiative aimed at improving the detection, treatment, and follow-up care of individuals at risk for glaucoma.

DESIGN

Retrospective analysis.

PARTICIPANTS

A total of 1649 individuals at risk for glaucoma who were examined and treated in 43 community centers located in underserved communities of Philadelphia.

METHODS

Individuals were enrolled if they were African American aged ≥50 years, were any other adult aged ≥60 years, or had a family history of glaucoma. After attending an informational glaucoma workshop, participants underwent a targeted glaucoma examination including an ocular, medical, and family history; visual acuity testing, intraocular pressure (IOP) measurement, and corneal pachymetry; slit-lamp and optic nerve examination; automated visual field testing; and fundus color photography. If indicated, treatments included selective laser trabeculoplasty (SLT), laser peripheral iridotomy (LPI), or IOP-lowering medications. Follow-up examinations were scheduled at the community sites after 4 to 6 weeks or 4 to 6 months, depending on the clinical scenario.

MAIN OUTCOME MEASURES

Detection rates of glaucoma-related diagnoses and types of treatments administered.

RESULTS

Of the 1649 individuals enrolled, 645 (39.1%) received a glaucoma-related diagnosis; 20.0% (n = 330) were identified as open-angle glaucoma (OAG) suspects, 9.2% (n = 151) were identified as having narrow angles (or as a primary angle closure/suspect), and 10.0% (n = 164) were diagnosed with glaucoma, including 9.0% (n = 148) with OAG and 1.0% (n = 16) with angle-closure glaucoma. Overall, 39.0% (n = 64 of 164) of those diagnosed with glaucoma were unaware of their diagnosis. A total of 196 patients (11.9%) received glaucoma-related treatment, including 84 (5.1%) who underwent LPI, 13 (0.8%) who underwent SLT, and 103 (6.2%) who were prescribed IOP-lowering medication.

CONCLUSIONS

Targeting individuals at risk for glaucoma in underserved communities in Philadelphia yielded a high detection rate (39.1%) of glaucoma-related diagnoses. Providing examinations and offering treatment, including first-line laser procedures, at community-based sites providing services to older adults are effective to improve access to eye care by underserved populations.