Telemedical diagnosis of anterior segment eye diseases: validation of digital slit-lamp still images

Validation of intraocular pressure measurement using tonometer AVIA across different postures: A Bland Altman analysis

AIMS/OBJECTIVES

Tonometry is a fundamental procedure in the diagnosis and management of glaucoma. Different tonometers have been proposed but none are as accurate as the Goldman applanation tonometry (GAT). Nonetheless, due to the limitations of GAT, mobile tonometry methods became prevalent. This study aims to examine the reliability of the Tono-Pen AVIA® (TPA) in measuring intraocular pressure (IOP) across different postures.

METHODS

A total of 196 eyes were prospectively examined for IOP changes using GAT and TPA. IOP measurements were taken across different postures using the TPA. Reliability of measurements was compared using interclass correlation coefficients (ICC), while agreement was represented using Bland-Altman analysis. Pearson r coefficient was used to measure correlations.

RESULTS

When compared to GAT (14.5 ± 4.4 mmHg), IOP readings were significantly higher for TPA at both seated (16.5 ± 4.5 mmHg; p < 0.001) and supine (16.9 ± 5.7; p < 0.001) positions. The ICC values for GAT and TPA among seated and supine patients were 0.79 (0.54-0.90) and 0.76 (0.48-0.87) indicating good reliability between the readings. There were significantly positive correlations between GAT and TPA at both seated (r = 0.626, p < 0.001) and supine (r = 0.727, p < 0.001) positions. Per Bland-Altman analysis, limits of agreement were -8.57 to 4.37 for GAT and seated TPA and -10.34 and 5.34 for GAT and supine TPA.

CONCLUSION

Good reliability exists between IOP measurements using GAT and TPA. However, the devices are not interchangeable and therefore cannot be used reciprocally in the same patient.

Evaluation of a telemedicine-enabled universal eye health delivery model in rural southern India

OBJECTIVES

To evaluate the accuracy of tele-ophthalmic examination (TOE) for common ocular conditions in comparison with the gold-standard in-person examination (IPE) for diagnosis and treatment advice.

METHODS

In a prospective, diagnostic accuracy validation study, we recruited 339 consecutive new patients, aged ≥16 years, visiting a vision centre (VC) associated with Aravind Eye Hospital in south India during January and February, 2020. All participants underwent the TOE, followed by IPE on the same visit. The in-person ophthalmologist was masked to the TOE diagnosis and treatment advice. Data were analysed via the sensitivity specificity of TOE versus the gold-standard IPE.

RESULTS

TOE achieved high sensitivity and specificity for identifying normal eyes with 87.4% and 93.5%, respectively. TOE had high sensitivity for cataracts (91.7%), infective conjunctivitis (72.2%), and moderate sensitivity for pterygium (62.5%), DR (57.1%), non-serious injury (41.7%), but low sensitivity for glaucoma (12.5%). TOE had high specificity ranging from 93.5% to 99.8% for all diagnoses. The sensitivity for treatment advice ranged from 58.1% to 77.2% and specificity from 96.9% to 100%.

CONCLUSIONS

The TOE in VCs has acceptable accuracy to an IPE by an ophthalmologist for correctly identifying and treating major eye ailments. Through providing universal eye care to rural populations, this model may contribute to work toward achieving Universal Health Coverage, which is a linchpin of the health-related U.N. Sustainable Development Goals (SDG).

Mobile infrared slit-light scanner for rapid eye disease screening

Purpose

Timely detection and treatment of visual impairments and age-related eye diseases are essential for maintaining a longer, healthier life. However, the shortage of appropriate medical equipment often impedes early detection. We have developed a portable self-imaging slit-light device utilizing NIR light and a scanning mirror. The objective of our study is to assess the accuracy and compare the performance of our device with conventional nonportable slit-lamp microscopes and anterior segment optical coherence tomography (AS-OCT) for screening and remotely diagnosing eye diseases, such as cataracts and glaucoma, outside of an eye clinic.

Approach

The NIR light provides an advantage as measurements are nonmydriatic and less traumatic for patients. A cross-sectional study involving Japanese adults was conducted. Cataract evaluation was performed using photographs captured by the device. Van-Herick grading was assessed by the ratio of peripheral anterior chamber depth to peripheral corneal thickness, in addition to the iridocorneal angle using Image J software.

Results

The correlation coefficient between values obtained by AS-OCT, and our fabricated portable scanning slit-light device was notably high. The results indicate that our portable device is equally reliable as the conventional nonportable slit-lamp microscope and AS-OCT for screening and evaluating eye diseases.

Conclusions

Our fabricated device matches the functionality of the traditional slit lamp, offering a cost-effective and portable solution. Ideal for remote locations, healthcare facilities, or areas affected by disasters, our scanning slit-light device can provide easy access to initial eye examinations and supports digital eye healthcare initiatives.

A proposed methodology for conducting a remote rigid gas permeable contact lens consultation

PURPOSE

COVID-19 spread to numerous countries, overwhelming healthcare systems and economies worldwide. COVID-19 restrictions have prevented patients from attending consultations in person and led to the further development of telemedicine to provide health care. The situation also applies to contact lens (CL) practitioners and their patients; telemedicine enables practitioners to provide patients with regular and continuing care. This study aimed to investigate available tools to enable continuing care for rigid gas permeable (RGP) CL wearers who are unable to attend face-to-face consultations.

METHODS

The study consists of three components. Firstly, an approach to enable the assessment of a patient's CL fitting and cornea remotely. Secondly, to find an affordable and reliable method to obtain a patient's visual acuity (VA), and thirdly, to develop a questionnaire to provide practitioners with information to deliver optimal patient care.

RESULTS

The use of a macro lens, smartphone, and auxiliary materials enables high-quality images of the anterior eye and RGP CL to be obtained. Two free and validated smartphone applications (apps) for VA measurements were identified which are available on Android and iOS systems. Two questionnaires were also developed to enable practitioners to obtain additional patient information to facilitate optimal patient care.

CONCLUSION

This study has developed the components of a remote CL consultation to enable patients who cannot attend scheduled appointments to receive care and advice to ensure the safety of their RGP CL wear. The tools involved in this study are low-cost, affordable, and an adjunct, not a substitute, for face-to-face consultations.

Telemedicine for Cornea and External Disease: A Scoping Review of Imaging Devices

OBJECTIVE

The objective of this scoping review is to understand the extent and type of evidence in relation to telemedicine imaging devices for cornea and external segment conditions.

INTRODUCTION

The coronavirus pandemic has emphasized the benefits of telemedicine in diagnosing and managing ocular diseases. With the rapid advancement of technology in slit lamp biomicroscopes, smartphones and other ocular surface imaging modalities, telemedicine applications for cornea and external diseases have become an active area of research.

INCLUSION CRITERIA

For studies to be included, they had to discuss the concept of imaging devices for cornea and external diseases in the context of telemedicine. There was no restriction on the studied population or participants.

METHODS

A scoping review was conducted according to an a priori protocol. Documents written in English were identified from the PubMed and Embase databases and searches. Anterior segment imaging devices were then classified into different categories.

RESULTS

Anterior segment imaging devices identified in this review included 19 slit lamp-based devices, 17 smartphone-based devices and 15 other devices. These tools can detect a wide variety of cornea and external diseases (e.g., pterygium, conjunctivitis, corneal opacity, corneal ulcer, and blepharitis). Fewer than half of the devices (24/51) were assessed for diagnostic performance. Their diagnostic accuracy varied greatly from condition to condition and from device to device. The inter-rater reliability of different photo-graders assessing images was assessed in only a few studies.

CONCLUSIONS

Anterior segment imaging devices are promising tools for remote diagnosis and management of patients with cornea and external disease. However, there are significant gaps in the literature regarding the diagnostic accuracy and inter-rater reliability of several devices. Future research with rigorous methods is required to validate the use of these devices in telemedicine settings.

Ocular conditions and injuries, detection and management in spaceflight

Ocular trauma or other ocular conditions can be significantly debilitating in space. A literature review of over 100 articles and NASA evidence books, queried for eye related trauma, conditions, and exposures was conducted. Ocular trauma and conditions during NASA space missions during the Space Shuttle Program and ISS through Expedition 13 in 2006 were reviewed. There were 70 corneal abrasions, 4 dry eyes, 4 eye debris, 5 complaints of ocular irritation, 6 chemical burns, and 5 ocular infections noted. Unique exposures on spaceflight, such as foreign bodies, including celestial dust, which may infiltrate the habitat and contact the ocular surface, as well as chemical and thermal injuries due to prolonged CO2 and heat exposure were reported. Diagnostic modalities used to evaluate the above conditions in space flight include vision questionnaires, visual acuity and Amsler grid testing, fundoscopy, orbital ultrasound, and ocular coherence tomography. Several types of ocular injuries and conditions, mostly affecting the anterior segment, are reported. Further research is necessary to understand the greatest ocular risks that astronauts face and how better we can prevent, but also diagnose and treat these conditions in space.

Portable Anterior Eye Segment Imaging System for Teleophthalmology

Objective

This study aims to compare a new prototype for a portable anterior eye segment imaging system with the standard method for ophthalmology examination.

Methods

The new imaging system consisted of two IMX219 Arducam autofocus sensors (Arducam, China, Nanjing) for Raspberry Pi V2 camera module connected to a Raspberry Pi Zero W (Raspberry Pi Foundation, UK, Cambridge) that clips to a wearable headset. The 2D videos of the anterior eye segment were recorded with the new system and a 720p FaceTime HD camera (Apple, Cupertino, CA). Afterward, ophthalmologists evaluated the videos using a standard clinical eye examination form. These evaluations were compared with the standard slit-lamp clinical assessment performed during the patient's visit.

Results

Thirty-five eyes were evaluated. The sensitivity and specificity percentages were statistically significant between the two imaging modalities (P ≤ 0.001). The evaluations performed from videos obtained with the new imaging system had better sensitivity and specificity percentages overall. However, statistically significant differences were only observed in cornea, anterior chamber, iris, and lens.

Conclusions

Specificity percentages were higher than sensitivity percentages in both imaging modalities, indicating that video evaluations are less accurate for pathological screening. Nevertheless, the new system evaluations were significantly better than the webcam evaluations.

Translational Relevance

This study presented an alternative system to assess eye conditions for telemedicine, one that provides more details than the current standard and uses new wearable headsets technologies.

Smartphone ophthalmoscopy versus slit-lamp biomicroscopy for optic nerve head evaluation: A digital apparatus into medical education

OBJECTIVE

Th aim of this study is to explore the diagnostic accuracy of smartphone-based D-EYE ophthalmoscopy in the diagnosis of optic nerve head (ONH) abnormalities and screening for glaucoma.

METHODS

This is a prospective clinical-based validation study performed on 90 patients recruited from a tertiary teaching hospital. Patients underwent dilated fundus examination by slit-lamp and smartphone-based D-EYE fundoscopy operated by two experienced ophthalmologists.

RESULTS

The diagnostic accuracy of smartphone-based D-EYE ophthalmoscopy of normal vertical cup-to-disc ratio (VCDR) was acceptable (sensitivity 85.8%-96.4%; specificity 51.4%-96.4%). The D-EYE would often underestimate VCDR values as mean VCDR was significantly lower among overall and glaucoma cohorts (all p-value <0.001) for D-EYE in comparison with slit-lamp. In terms of ONH abnormalities, the D-EYE adequately demonstrated high sensitivity in the identification of only margins-related abnormalities (sensitivity 92.5%-96.6%). Overall, the diagnostic accuracy and agreement between expert ophthalmologists using the D-EYE and the reference slit-lamp examination were significantly poor.

CONCLUSION

We demonstrated that the D-EYE is a highly specific tool for VCDR within the normal range but not in patients with glaucoma. Despite being an easy and portable tool to measure VCDR, it is limited in terms of diagnosing ONH and blood vessel abnormalities.

A smartphone lens attachment improves the quality of referrals to eye casualty

Background/objectives

In recent years, eye casualty clinics have seen significant increases in patient numbers with reduced capacity. COVID-19 has exacerbated this issue and demonstrated the potential of telemedicine as a solution. Our study evaluated the potential benefit of a smartphone-based lens attachment to improve the referral pathway for anterior segment related complaints in eye casualty.

Subjects/methods

Fifty-four consecutive patients with anterior segment complaints were recruited. A questionnaire was completed with each patient to simulate the history from the point of referral. White light and cobalt blue photos were captured using a smartphone lens. The clinician reviewing the patient was asked to document the actual diagnosis and the appropriate time-frame within which they felt the patient could safely have been seen within; both with and without the option of management advice at the time of triage. The subsequent images and questionnaires were reviewed by a single consultant Ophthalmologist who was independent to the data collection process. The assessor was asked to make a diagnosis and management plan based upon the questionnaire (‘History’), and the questionnaire with the photo (‘History with Image’), as well as rate their clinical confidence on a 1–5 scale.

Results

Diagnostic accuracy was significantly higher in “History with Image” (98.2%), when compared to “History” only (48.2%). “History with Image” prevented significantly more appointments when compared to “History” alone, at similar levels to retrospective clinic review. Preventable appointments were increased if clinical advice was possible. Timeframe of appointments between ‘History with Image’ and ‘Clinic’ appointments was similar. Clinical’Confidence was significantly higher at 4.5 with ‘History with Image’ when compared to 2.37 with ‘History Only’.

Conclusion

A low-cost smartphone lens attachment, alongside a standardised clinical questionnaire, can improve the referral pathway to the hospital eye service by reducing unnecessary appointments, while improving clinical confidence and diagnostic accuracy during triage. Further work to evaluate referral pathways, including the development of systems that allow for secure image transmission are needed to understand the feasibility for the widespread adoption of this technology.

Efficiency when scanning old ophthalmologic slides

OBJECTIVE

To digitise our old archive and evaluate the efficiency of this task, both in medical and economic terms.

MATERIAL AND METHODS

All slides and negatives (8254) archived in our clinic were collected, digitised with a 5-megapixel slide scanner. The images were taken from 1972 to 1999. Quality and utility of images were taken into account, as far as costs of the task (up to 2100 euros), all the work done by the same ophthalmologist.

RESULTS

Of those identifiable, 62% of the patients had already died. Only 1.5% were archived for use; 70 images for teaching reasons and 60 for medical reasons, being incorporated into the patient's history. About 210h were spent on scanning, identifying, checking and uploading images. 84% corresponded to retinal pathology, 4% to glaucomatous pathology, 3% to anterior segment pathology and the last 9% to learning material. The quality of most images is good, and, in some cases, were important for the correct diagnosis of the pathology. If only medical reasons are taken into account, the number of images uploaded is very low when working with archives older than 50 years.

CONCLUSIONS

Although there was a low percentage of scanned images, the task was efficient because of a low cost. Images older than 50 years must be evaluated before scanning because of their low utility.

An image-based eyelid lesion management service-evaluation of a pilot

BACKGROUND/AIMS

Oculoplastics is a predominantly visual specialty and many of the pathologies can be diagnosed based on external appearance. An image-based eyelid lesion management service was piloted to reduce the number of patients who would require outpatient clinic review. The aim of this study was to determine its accuracy and feasibility, both as a hospital-based and community optometrist-based service. If successful, the service was envisaged to significantly reduce the number of patients that require face-to-face (F2F) review, in accordance with current post-COVID-19 principles of social distancing.

METHODS

Patients with lid lesions attending an oculoplastics clinic were assessed by consultant oculoplastic surgeons in an F2F consultation (Arm A). The lesions were photographed by a professional clinical photographer (Arm B) and by an optometrist with a handheld digital camera (Arm C). These images were reviewed by independent consultants masked to the outcome of the F2F clinical encounter. Data were collected prospectively including patient demographics, diagnosis, suspicion of malignancy and management. The image-based clinic results were compared to the F2F clinic results.

RESULTS

Ninety-five patients were included. Clinical diagnoses were compared for intra-observer variability and substantial agreement was demonstrated between gold-standard F2F clinic visit (Arm A) and Arm B (Ƙ = 0.708) and C (Ƙ = 0.776). There was no statistically significant difference in the rate of discharge and all cases of malignancy were either identified or flagged for F2F review in the image-based arms.

CONCLUSION

This pilot demonstrated substantial diagnostic agreement of image-based diagnoses with F2F consultation and image review alone did not miss any cases of malignancy.

Ophthalmic Telesurgery with a Low-Cost Smartphone Video System for Surgeon Self-Reflection and Remote Synchronous Consultation: A Qualitative and Quantitative Study

SUMMARY

More than a third of the global burden of blindness is due to cataracts, yet cataract surgery is one of the most cost-effective surgical treatments in medicine. Poor surgical outcomes in many settings remain a major challenge, raising concerns about the quality and efficacy of surgical training. Reflective learning from video recordings of a trainees' surgical performance has a high educational impact and is available routinely for surgical training within high-resource institutions. However, the prohibitive cost and limited portability of current surgical video recording systems make its use problematic in low-resource settings and outreach environments.

OBJECTIVE

The study's aim was to evaluate the potential of smartphone-captured surgical videos for surgeon learning via self-recording and self-review as well as the potential to support live telesurgical consultation.

METHODOLOGY

A quantitative and qualitative methodology was used to explore and describe the utility and acceptance of smartphone videos in two training facilities in Nepal. Twenty surgeries were recorded on the smartphone for surgeon self-review, to assess image quality, and its application to measure performance against the International Council of Ophthalmology (ICO) Ophthalmology Surgical Competency Assessment Rubrics (OSCAR) SICS Rubric. The same system was used to transmit 15 different surgeries live via Skype from Nepal to an ophthalmologist surgical trainer in South Africa to evaluate the feasibility of live consultation.

FINDINGS

Overall video quality was described as high in 65% and moderate in 35% for the videos recorded for self-review. In the surgeries streamed via Skype, quality was described as high in 92.9% and moderate in 7.1%. There were no instances where the video quality was described as poor. The video quality was good enough that the surgeons could measure against ICO-OSCAR rubric in all cases.

DISCUSSION

The video quality of smartphone-captured surgical videos was found to be high and gained acceptance for reflective teaching and learning purposes. The extended telesurgical potential and portability of the smartphone enables use across many settings. More studies over a longer period are needed to determine how they can support training and learning in cataract surgery.

Design and Performance Characterization of a Novel, Smartphone-Based, Portable Digital Slit Lamp for Anterior Segment Screening Using Telemedicine

Purpose

Telemedicine-enabled, portable digital slit lamps can help to decentralize screening to close-to-patient contexts. We report a novel design for a portable, digital slit lamp using a smartphone. It works on an advanced optical design and has the capability of instantaneous, objective photodocumentation to capture anterior segment images and is telemedicine-enabled.

Methods

The device is constructed keeping its usability and the importance of design ergonomics for nonspecialized field personnel in mind. The optical design is described, and the resolution and magnification are compared with traditional desktop-based slit lamps. A Health Insurance Portability and Accountability Act (HIPAA)–compliant, patient management software is integrated to synchronize the captured images with a secure cloud server along with a sharpness algorithm to extract the best focused frames of the cornea, iris, and lens, from videos. We demonstrate its photodocumentation ability and teleophthalmology feasibility by capturing images in a pilot study from nine subjects.

Results

Images were obtained in various illumination, magnification, and filter settings. Synchronous and asynchronous teleophthalmology consults were conducted. The performance of the device was shown to be limited by the smartphone sensor resolution and not the optical design, because the Air Force target resolution was found to be the same on smartphone-mounted traditional slit lamps despite a lower magnification.

Conclusions

The novel, portable, digital slit lamp with advanced optical design using smartphones has the ability to screen for anterior segment pathologies using telemedicine.

Translational Relevance

A portable, telemedicine-friendly, ergonomically designed, slit lamp used by nonspecialist personnel allows for both synchronous and asynchronous modes of consultation at remote locations, facilitating mass screening programs.

Anterior Segment and Others in Teleophthalmology: Past, Present, and Future

ABSTRACT

Teleophthalmology, a subfield of telemedicine, has recently been widely applied in ophthalmic disease management, accelerated by ubiquitous connectivity via mobile computing and communication applications. Teleophthalmology has strengths in overcoming geographic barriers and broadening access to medical resources, as a supplement to face-to-face clinical settings. Eyes, especially the anterior segment, are one of the most researched superficial parts of the human body. Therefore, ophthalmic images, easily captured by portable devices, have been widely applied in teleophthalmology, boosted by advancements in software and hardware in recent years. This review aims to revise current teleophthalmology applications in the anterior segment and other diseases from a temporal and spatial perspective, and summarize common scenarios in teleophthalmology, including screening, diagnosis, treatment, monitoring, postoperative follow-up, and tele-education of patients and clinical practitioners. Further, challenges in the current application of teleophthalmology and the future development of teleophthalmology are discussed.

A Review of Ophthalmic Telemedicine for Emergency Department Settings

BACKGROUND

Patients presenting to emergency departments for ophthalmic emergencies benefit from prompt evaluation. However, Few emergency departments (EDs) have ophthalmologists on call, and eye care provided in EDs without ophthalmic services can be inaccurate.

METHODS

We review the current state of ophthalmic telemedical care in EDs and highlight important considerations when implementing telemedicine in this setting.

RESULTS

Telemedicine allows ophthalmologists to work with on-site emergency care providers to interview and examine patients remotely in EDs, enabling proper assessment of patient history, visual acuity, pupils, intraocular pressure, as well as the anterior and posterior segment. To date, patients' perceptions of this new model of care have been largely positive.

DISCUSSION

The use of telemedical consultations for remote evaluation of patients with ophthalmic complaints stands to improve the quality of care provided to patients and extend the reach of remote ophthalmologists. The onset of the COVID-19 pandemic and the risk of in-person care further highlights the potential for telemedicine to augment existing models of emergency care.

A novel approach to anterior segment imaging with smartphones in the COVID-19 era

Purpose:

To report a novel, telemedicine-friendly, smartphone-based, wireless anterior segment device with instant photo-documentation ability in the COVID-19 era.

Methods:

Anterior Imaging Module (AIM) was constructed based on a 50/50 beam splitter design, to match the magnification drum optics of slit-lamps with a three-step or higher level of magnification. The design fills the smartphone sensor fully at the lowest magnification and matches the fixed focus of the slit-lamp. It comes with a smartphone for instant photo-documentation, an in-built software application for data-management and secure HIPAA compliant cloud storage, and a Bluetooth trigger for a one-tap image capture. The construction of the device is explained, and the optical resolution measured using U.S. air-force resolution test. AIM’s performance was characterized with traceability to internationally relevant performance standards for digital slit-lamps after image quality assessment through a pilot study.

Results:

Clinically useful anterior segment images were obtained with both diffuse and slit illumination at different magnification settings with the highest magnification (40X) resolution of 359 lines per cm and the lowest magnification (16X) resolution of 113 lines per cm.

Conclusion:

AIM is a novel, wireless, telemedicine-enabled design that digitizes existing, analog slit lamps with at least three-step magnification. The settings ensure the focus is determined purely by the position of the slit-lamp. Hence, the image viewed and captured on the smartphone is exactly what the clinician sees through the eyepiece. This helps in maintaining distance from the patient in the ongoing COVID-19 pandemic, as well.

Automatic classification of heterogeneous slit-illumination images using an ensemble of cost-sensitive convolutional neural networks

Background

Lens opacity seriously affects the visual development of infants. Slit-illumination images play an irreplaceable role in lens opacity detection; however, these images exhibited varied phenotypes with severe heterogeneity and complexity, particularly among pediatric cataracts. Therefore, it is urgently needed to explore an effective computer-aided method to automatically diagnose heterogeneous lens opacity and to provide appropriate treatment recommendations in a timely manner.

Methods

We integrated three different deep learning networks and a cost-sensitive method into an ensemble learning architecture, and then proposed an effective model called CCNN-Ensemble [ensemble of cost-sensitive convolutional neural networks (CNNs)] for automatic lens opacity detection. A total of 470 slit-illumination images of pediatric cataracts were used for training and comparison between the CCNN-Ensemble model and conventional methods. Finally, we used two external datasets (132 independent test images and 79 Internet-based images) to further evaluate the model's generalizability and effectiveness.

Results

Experimental results and comparative analyses demonstrated that the proposed method was superior to conventional approaches and provided clinically meaningful performance in terms of three grading indices of lens opacity: area (specificity and sensitivity; 92.00% and 92.31%), density (93.85% and 91.43%) and opacity location (95.25% and 89.29%). Furthermore, the comparable performance on the independent testing dataset and the internet-based images verified the effectiveness and generalizability of the model. Finally, we developed and implemented a website-based automatic diagnosis software for pediatric cataract grading diagnosis in ophthalmology clinics.

Conclusions

The CCNN-Ensemble method demonstrates higher specificity and sensitivity than conventional methods on multi-source datasets. This study provides a practical strategy for heterogeneous lens opacity diagnosis and has the potential to be applied to the analysis of other medical images.

Alleviating an Increasingly Burdened Healthcare System with Telemedicine: Anterior Segment

Tele-ophthalmology is a rapidly evolving and exciting field that has become increasingly relevant amidst the current global pandemic. With advancements in technology, many components of an evaluation previously possible only in an office setting are becoming possible remotely, paving the way for at-home visits. Examples of these technologies include measurement of visual acuity using smartphones, remote monitoring of intraocular pressure using self-administered tonometers or implantable sensors, and use of digitally acquired slit-lamp or smartphone images for diagnosis of anterior segment pathology. While many examples showcasing the utility of telemedicine have been shown for diseases such as diabetic retinopathy, concerted efforts are needed to develop similar technology for anterior segment diseases. As technology continues to advance, it may be possible to diagnose and manage more anterior segment disease with telemedicine.

Evaluation of digital slit-lamp videos for paediatric anterior segment telemedicine consultations

INTRODUCTION

This study aimed to assess the validity of telemedicine consultations using digital slit-lamp videos to detect anterior segment pathology in a paediatric population.

METHODS

A paediatric anterior segment specialist simultaneously performed and recorded anterior segment examinations using the Topcon digital-ready slit lamp. Components of the examination included the eyelids/eyelashes, conjunctiva/sclera, cornea, anterior chamber, iris and lens. Masked to clinical findings, a paediatric ophthalmologist reviewed and graded the live video feed transmitted at 4 Mbps. At least three months later, both ophthalmologists graded the stored videos. We compared the sensitivity, specificity, percent agreement and weighted kappa (κ) of diagnosing anterior segment pathologies via live-streamed and store-and-forward video clips compared to the in-person standard examination.

RESULTS

Examinations of 89 eyes from 45 children (5-17 years old) with known anterior segment pathology were included. Agreement between live-streamed and in-person standard examinations for conjunctiva/sclera, anterior chamber, iris and lens findings was almost perfect (sensitivity 89-96%, specificity 95-100%, κ = 0.87-0.97). Substantial agreement was found for cornea pathology (sensitivity 88%, specificity 90%, κ = 0.72), and moderate agreement was found for eyelids/eyelashes pathology (sensitivity 54%, specificity 92%, κ = 0.46). Store-and-forward results were similar, though slightly better for eyelids/eyelashes and slightly worse for conjunctiva/sclera.

DISCUSSION

Digital slit-lamp videos hold promise for synchronous and asynchronous telemedicine in diagnosing paediatric anterior segment pathologies.

Law and order of modern ophthalmology: Teleophthalmology, smartphones legal and ethics

In recent years, new technologies used in the field of ophthalmology have been emerging and developing rapidly. Two major aspects of these advancements are teleophthalmology and smartphones, which have enabled practitioners to achieve optimal outcomes in record time with minimal costs. Several rules and regulations have been applied to these technologies in order to frame them under the appropriate medico-legal ethics, and specialized committees have been dedicated to maintaining their efficacy and avoiding shortcomings. In addition multiple studies and case reports conducted worldwide have assessed them according to specific diseases or global concerns. This review article constitutes an up-to date account of almost all of the applications and medico-legal perspectives of technologies used in ophthalmology in order to summarize and better visualize their advantages and disadvantages.

Could telehealth help eye care practitioners adapt contact lens services during the COVID-19 pandemic?

The COVID-19 pandemic has necessitated government-imposed restrictions on social interactions and travel. For many, the guidance has led to new ways of working, most notably a shift towards working remotely. While eye care practitioners (ECPs) may continue to provide urgent or emergency eye care, in many cases the travel restrictions present a unique challenge by preventing conventional face-to-face examination. Telephone triage provides a useful starting point for establishing at-risk and emergency patients; but patient examination is central to contact lens patient care. The indeterminate period over which conventional practice will be suspended, and the risk that resumption of 'normal' practice could be impeded by a potential secondary peak in COVID-19 cases, hastens the need for practitioners to adapt their delivery of eyecare. Specifically, it is prudent to reflect upon supportive evidence for more comprehensive approaches to teleoptometry in contact lens practice. Smartphone based ocular imaging is an area which has seen considerable growth, particularly for imaging the posterior eye. Smartphone imaging of the anterior eye requires additional specialised instrumentation unlikely to be available to patients at home. Further, there is only limited evidence for self-administered image capture. In general, digital photographs, are useful for detection of gross anterior eye changes, but subtle changes are less discernible. For the assessment of visual acuity, many electronic test charts have been validated for use by practitioners. Research into self-administered visual acuity measures remains limited. The absence of a comprehensive evidence base for teleoptometry limits ECPs, particularly during this pandemic. Knowledge gaps ought to be addressed to facilitate development of optometry specific evidence-based guidance for telecare. In particular, advances in ocular self-imaging could help move this field forwards.

Novel Use of Telemedicine for Corneal Tissue Evaluation in Eye Banking: Establishing a Standardized Approach for the Remote Evaluation of Donor Corneas for Transplantation

PURPOSE

To determine the feasibility of using telemedicine consultations in the evaluation of recovered donor corneas for transplant suitability.

METHODS

This study aims to establish and test the minimum imaging requirements for telemedical consultations of corneal tissue by remote eye bank medical directors. Digital images from the slit lamp, optical coherence tomography, and/or specular microscope were assembled into telemedical consults and emailed to 4 eye bank medical directors (M.A.T., J.W., C.S.S., N.K.R.). Feedback on the minimum image requirements for each corneal finding was collected. After establishing a standardized imaging and presentation protocol, test cases were presented to the medical directors to examine the validity of these remote consults. To establish a benchmark for the study's parameters, one medical director (J.W.) examined each case in person after his initial remote review. Examiners were masked to each other's responses.

RESULTS

Minimum image requirements for determination of corneal findings were defined and were specific to each anatomic layer of the cornea (epithelial, stromal, or endothelial). Using a defined set of digital images for a set of common corneal findings, the rate of agreement between remote evaluators, eye bank staff, and the in-person evaluator was 100% (11 of 11 examples). For ambiguous test cases, remote evaluators agreed on 80% of the cases (4 of 5).

CONCLUSIONS

Results from this pilot study suggest that telemedical review of corneal tissue using high-quality digital images may be adequate for accurate identification of specific corneal findings commonly encountered by eye banks.

Comparison of different smartphone cameras to evaluate conjunctival hyperaemia in normal subjects

Despite the significant advantages that smartphones’ cameras can provide in teleophthalmology and artificial intelligence applications, their use as black-box systems for clinical data acquisition, without adequate information of the quality of photographs can compromise data accuracy. The aim of this study is to compare the objective and subjective quantification of conjunctival redness in images obtained with calibrated and non-calibrated cameras, in different lighting conditions and optical magnifications. One hundred ninety-two pictures of the eye were taken in 4 subjects using 3 smartphone cameras{Bq, Iphone, Nexus}, 2 lighting levels{high 815 lx, low 122 lx} and 2 magnification levels{high 10x, low 6x}. Images were duplicated: one set was white balanced and color corrected (calibrated) and the other was left as it was. Each image was subjective and objectively evaluated. There were no significant differences in subjective evaluation in any of the conditions whereas many statistically significant main effects and interaction effects were shown for all the objective metrics. The clinician’s evaluation was not affected by different cameras, lighting conditions or optical magnifications, demonstrating the effectiveness of the human eye’s color constancy properties. However, calibration of a smartphone’s camera is essential when extracting objective data from images.

Teleophthalmic Approach for Detection of Corneal Diseases: Accuracy and Reliability

PURPOSE

Corneal and anterior segment diseases cause most of the urgent visits to eye care professionals. We evaluated the diagnostic accuracy of detecting corneal diseases using external photographs from 2 portable cameras for telemedicine purposes.

METHODS

This is a prospective study of adults with a clinical diagnosis of corneal pathology including corneal abrasions, ulcers, scars, and pterygia. A cornea specialist provided the gold standard diagnosis by slit-lamp examination. Images of both eyes were obtained using iTouch 5S and Nidek VersaCam cameras in multiple gazes and interpreted by 3 cornea specialists for the presence of pathology. Accuracy to detect disease was compared with gold standard diagnosis, stratified by the camera and grader. Reliability was evaluated with weighted kappa statistics. Graders assessed image quality on a Likert scale from 1 (poor) to 9 (optimal).

RESULTS

A total of 198 eyes (110 subjects) were photographed. By gold standard diagnosis, 59 eyes (30%) had corneal scars, 34 (17%) had ulcers, 13 (7%) had abrasions, 10 (5%) had pterygia, and 82 (41%) were normal. Sensitivity to detect AS pathology ranged from 54% to 71% for the iTouch and 66% to 75% for the Nidek, across graders; specificity ranged from 82% to 96% for the iTouch and 91% to 98% for the Nidek. The intergrader reliability was moderate to strong (kappa ranges: 0.54-0.71 for the iTouch; 0.75-0.76 for the Nidek). Quality ratings were variable between graders.

CONCLUSIONS

External photographs taken by standard, nonenhanced portable cameras and interpreted remotely by ophthalmologist graders yielded sensitivity values that are not yet suitable for telemedicine applications. Additional work is needed to improve the ability to detect AS pathology remotely.

A Remote Operating Slit Lamp Microscope System

Objectives: To develop a remote-operating slit lamp microscope system (the remote slit lamp) as the core for highly specialized ophthalmology diagnoses, and to compare the utility of this system with the conventional slit lamp microscope system (the conventional slit lamp) in making a diagnosis.

Methods: The remote slit lamp system was developed. Three factors were evaluated in comparison to the conventional slit lamp. The ability to acquire skills was investigated using a task loading system among specialists and residents in ophthalmology. Participants repeated a task up to ten times and the time required for each task was analyzed. The consistency of the two systems in making a diagnosis was investigated using eyes of patients with ocular diseases as well as healthy volunteers.

Results: The remote slit lamp is composed of a patient’s unit and ophthalmologist’s unit connected by high-speed internet. The two units share images acquired by the slit lamp in addition to the images and voices of patients and ophthalmologists. Both ophthalmology specialists and residents could minimize the completion times after several trials. The remote slit lamp took more time than the conventional slit lamp. Both systems showed a high consistency in evaluations among eyes with healthy eyes or those with ocular diseases.

Conclusions: The remote slit lamp has a similar diagnostic ability, but required more examination time in comparison to the conventional slit lamp. The currently developed remote slit lamp has the potential to be employed for telemedicine purposes in the field of ophthalmology.

Comparing smartphone camera adapters in imaging post-operative cataract patients

Introduction The goal of this study is to compare image quality and clinical confidence for managing post-operative cataract patients based on anterior segment smartphone images obtained in real-world settings using four types of adapters: (a) macro lens (ML), (b) ML with augmented light-emitting diode (LED) illumination (ML-LED), (c) no adapter (NA) and (d) slit lamp (SL) adapter. Methods Anterior segment images were obtained from 190 eyes after cataract surgery using an eight-megapixel iPhone 6 smartphone camera with four adapters: ML, ML-LED, NA, and SL. Smartphone images were subjectively rated by ophthalmologists as acceptable or not acceptable for: (a) image quality for evaluating the anterior segment structures and (b) reader confidence in clinically managing post-operative patients based on smartphone images. Results NA, ML-LED, and SL had the highest scores for image quality with 100%, 93.7%, and 86.3% judged as acceptable, respectively. NA, SL, and ML-LED were also rated highest in clinical confidence with 100%, 98%, and 93.2% having acceptable levels, respectively. ML was judged lowest in both image quality (61.1% acceptable) and clinical confidence (37.4% acceptable). Discussion This study represents the first effort to compare different smartphone camera adapters' ability to image the anterior segment of the eye in a real-world setting. Our study shows that ML-LED, NA, and SL adapters were acceptable for visualizing anterior segment structures to physician readers in 86-100% of cases. When coupled with visual acuity, intro-ocular pressure and history, these images can result in acceptable clinical confidence in 93-100% of cases.

Telemedicine for ophthalmic consultation services: use of a portable device and layering information for graders

Introduction We compared remote, image-based patient consultations to in-person consultations at emergency department and inpatient hospital settings. Methods Patients evaluated by the ophthalmic consultation services (gold standard) were imaged over a two-week period. A trained study coordinator took anterior segment photographs (AS) and posterior segment photographs (PS) with a portable camera (PictorPlus, Volk Optical, Cleveland, OH). Ophthalmologists (graders) determined photograph quality, presence of pathology, and their confidence in disease detection. At a separate session, graders reassessed photographs accompanied by a one-sentence summary of demographics and chief complaint (CHx). We computed accuracy and reliability statistics. Results We took AS photographs of 24 eyes of 15 patients and PS photographs of 39 eyes of 20 patients. The majority of images were rated as acceptable or excellent in quality (AS: 89-96%; PS: 70-75%). Graders detected AS pathology with 62-81% sensitivity based on photographs, increasing to 87-88% sensitivity with photographs plus CHx. Graders detected PS pathology with 79-86% sensitivity based on a photograph only, increasing to 100% sensitivity with photographs plus CHx. Discussion In this pilot study, there is evidence that portable ophthalmic imaging technologies could enable ophthalmologists to remotely evaluate anterior and posterior segment eye diseases with good sensitivity. The ophthalmologist could detect ocular pathology on photographs more accurately if they were provided brief clinical information.

Slitlamp Photography and Videography With High Magnifications

PURPOSE

To demonstrate the use of the slitlamp photography and videography with extremely high magnifications for visualizing structures of the anterior segment of the eye.

METHODS

A Canon 60D digital camera with Movie Crop Function was adapted into a Nikon FS-2 slitlamp to capture still images and video clips of the structures of the anterior segment of the eye. Images obtained using the slitlamp were tested for spatial resolution. The cornea of human eyes was imaged with the slitlamp, and the structures were compared with the pictures captured using the ultra-high-resolution optical coherence tomography (UHR-OCT). The central thickness of the corneal epithelium and total cornea was obtained using the slitlamp, and the results were compared with the thickness obtained using UHR-OCT.

RESULTS

High-quality ocular images and higher spatial resolutions were obtained using the slitlamp with extremely high magnifications and Movie Crop Function, rather than the traditional slitlamp. The structures and characteristics of the cornea, such as the normal epithelium, abnormal epithelium of corneal intraepithelial neoplasia, laser in situ keratomileusis interface, and contact lenses, were clearly visualized using this device. These features were confirmed by comparing the obtained images with those acquired using UHR-OCT. Moreover, the tear film debris on the ocular surface and the corneal nerve in the anterior corneal stroma were also visualized. The thicknesses of the corneal epithelium and total cornea were similar to that measured using UHR-OCT (P<0.05).

CONCLUSIONS

We demonstrated that the slitlamp photography and videography with extremely high magnifications allow better visualization of the anterior segment structures of the eye, especially of the epithelium, when compared with the traditional slitlamp.

Diabetic retinopathy screening with pharmacy-based teleophthalmology in a semiurban setting: a cost-effectiveness analysis

BACKGROUND

Diabetic eye complications are the leading cause of visual loss among working-aged people. Pharmacy-based teleophthalmology has emerged as a possible alternative to in-person examination that may facilitate compliance with evidence-based recommendations and reduce barriers to specialized eye care. The objective of this study was to estimate the cost-effectiveness of mobile teleophthalmology screening compared with in-person examination (primary care) for the diabetic population residing in semiurban areas of southwestern Ontario.

METHODS

A decision tree was constructed to compare in-person examination (comparator program) versus pharmacy-based teleophthalmology (intervention program). The economic model was designed to identify patients with more than minimal diabetic retinopathy, manifested by at least 1 microaneurysm at examination (modified Airlie House classification grade of ≥ 20). Cost-effectiveness was assessed as cost per case detected (true-positive result) and cost per case correctly diagnosed (including true-positive and true-negative results).

RESULTS

The cost per case detected was $510 with in-person examination and $478 with teleophthalmology, and the cost per case correctly diagnosed was $107 and $102 respectively. The incremental cost-effectiveness ratio was $314 per additional case detected and $73 per additional case correctly diagnosed. Use of pharmacologic dilation and health care specialists' fees were the most important cost drivers.

INTERPRETATION

The study showed that a compound teleophthalmology program in a semiurban community would be more effective but more costly than in-person examination. The findings raise the question of whether the benefits of pharmacy-based teleophthalmology in semiurban areas, where in-person examination is still available, are equivalent to those observed in remote communities. Further study is needed to investigate the impact of this program on the prevention of severe vision loss and quality of life in a semiurban setting.

Global teleophthalmology with iPhones for real-time slitlamp eye examination

PURPOSE

To evaluate the image resolutions in global teleophthalmology using 2 smartphones.

METHODS

A standard resolution test card and two human eyes (one eye wearing a contact lens) were imaged with an iPhone 4S adapted for slitlamp biomicroscopy in Hangzhou, Zhejiang, China. An iPhone 5 was used as a receptor on the other side of the world (Miami, FL). The real-time images and still images were transferred through Skype from Hangzhou to Miami during slitlamp eye examination. The real-time resolutions captured and displayed on the both phones at different places were measured. There was vocal communication concurrent between two parties during image transference and the examination by the slitlamp biomicroscopy performed in Hangzhou.

RESULTS

The real-time and still images were transferred between two cities while two operators talked with each other smoothly and without difficulty. The viewer in Miami was able to instruct the operator in Hangzhou to thoroughly examine the eye using the slitlamp microscopy with different magnification settings and illumination settings. The resolution of the still images recorded in the iPhone in Hangzhou was higher than that of the real-time images on the screen. The main features of the eye were recognizable in real-time.

CONCLUSIONS

The study demonstrated that global teleophthalmology is feasible using two smartphones. The system is simple, portable, and affordable, and the image quality in still and real-time images is acceptable for real-time teleophthalmology.

Telemedicine for corneal disease in rural Nepal

We evaluated the diagnostic accuracy of slit-lamp photographs interpreted by telemedicine compared to a conventional clinical examination. A convenience sample of 21 patients with anterior segment disease was enrolled at the Lumbini Eye Institute (LEI) in Bhairahawa, Nepal. An ophthalmologist at the LEI examined each patient and assigned a diagnosis and follow-up interval; this represented the gold standard. An ophthalmic technician also obtained anterior segment photographs of each patient. Slit-lamp photographs and clinical histories were then uploaded to a server for access by three separate readers. These readers, one in Nepal and two in the US, provided a diagnosis and follow-up interval independently. The diagnostic agreement between the examiner and all readers was good (kappa = 0.75, P < 0.0001). The agreement regarding follow-up interval between the examiner and all readers was fair, with a kappa coefficient of 0.32 (P < 0.0001). However, the agreement was high when comparing the examiner with the reviewer in Nepal (kappa = 0.90) and was moderate when comparing the two US-based readers with each other (kappa = 0.45). In general, the ophthalmologists in Nepal recommended more rapid follow-up than their US-based counterparts. Our results suggest that the transmission of slit-lamp photographs from satellite clinics and eye health screening camps to the LEI and elsewhere for review and triage is an effective means of identifying anterior segment pathology.

Objectifying the conjunctival provocation test: photography-based rating and digital analysis

BACKGROUND

Patients with allergic rhinoconjunctivitis are susceptible to both nasal and ocular symptoms. The conjunctival provocation test (CPT) is an established diagnostic procedure used in allergic rhinoconjunctivitis, particularly to document a patient's current reactivity to allergens. To date, there are no international guidelines defining the CPT. No approved evaluation method exists for interpreting CPT results. This paper aims to establish the digital analysis of macroimages as an objective, validated and standardized method for interpreting CPT results.

METHODS

In a clinical immunotherapy trial with 155 patients, treatment progress was documented based on the CPT. Local investigators used a symptom score to grade tearing, reddening and the patients' subjective perception of symptoms (mucosal irritation). A central observer rated conjunctival hyperemia via digital photography. Digital image analysis software was utilized to determine conjunctival hyperemia.

RESULTS

Spearman's correlation between the local investigators' and the central observer's ratings was r = 0.729 (p < 0.001); the percentage of total agreement was 48% (based on 739 photos). Digital image analysis (based on 48 photos) had a high percentage of total agreement with the central observer's ratings (69%) but a low percentage of total agreement with the investigators' ratings (38%). The corresponding correlations were r = 0.264 and 0.064, respectively.

CONCLUSION

Photography-based rating by a central observer may represent a valuable supplement to the local investigator's assessment for making an objective evaluation of CPT results. Digital image analysis possesses the potential of being an objective evaluation method compared to the wide-spread subjective evaluation by the investigators.