Teleophthalmology


Teleophthalmology is a branch of telemedicine that delivers eye care through digital medical equipment and telecommunications technology. Today, applications of teleophthalmology encompass access to eye specialists for patients in remote areas, ophthalmic disease screening, diagnosis and monitoring; as well as distant learning.
Teleophthalmology offers several advantages. It eliminates the need for patients to travel to major medical centers or endure long wait times for specialist appointments. Instead, trained technicians or nurses can acquire eye images, typically fundus photographs and optical coherence tomography scans, and transmit them securely online to ophthalmologists for review. This allows for efficient triage, identifying patients requiring in-person examinations and determining the urgency of their needs. Teleophthalmology provides a cost-effective diagnostic method, particularly beneficial in reaching remote populations and screening individuals at higher risk of eye diseases, such as those with diabetes.

Implementation

Although ocular photography has been present since the early 1980s, the transfer of digital images from one location to another for assessment is a relatively recent phenomenon. The rise of digital imaging in the early 1990s allowed ophthalmologists and optometrists to capture images and store them on computers for future assessment. The advent of the Internet allowed for the digital transfer of these ocular images from one location to another.
Current teleophthalmological solutions are generally focused on a particular eye problem, such as diabetic retinopathy, retinopathy of prematurity, macular degeneration, strabismus and adnexal eye diseases. Less common conditions that can be revealed using retinal images are arterial and vein occlusions, chorioretinitis, congenital anomalies, and tapetoretinal abitrophy. Several population-based studies have used retinal imaging to relate ophthalmic abnormalities to general conditions, including hypertension, renal dysfunction, cardiovascular mortality, subclinical and clinical stroke, and cognitive impairment.
Mobile applications are widely available in ophthalmology and optometry as tools for eye tests and for educational purposes. Technological advancements in digital ocular imaging devices are perceived by many as key drivers for teleophthalmology. Recently, emerging retinal imaging modalities such as optical coherence tomography are capable of producing digital images of the retina with a micrometer resolution, which can be transmitted for research or diagnostic purposes. Along with systems designed for health care professionals, patient-centred systems such as for use by the general public are emerging.

Process

Fundus photography is performed by a fundus camera, which basically consists of a specialized low power microscope with an attached camera.
Teleophthalmology services can be provided primarily in two ways synchronously or asynchronously:
  • Synchronous teleophthalmology enables real-time interaction between participants, synchronous to supervise the removal of corneal foreign bodies and for consultations.
  • Asynchronous teleophthalmology in a "store-and-forward" method, where data is captured and transmitted for review at a later time.
Images of the eye can be captured non-invasively through various methods, generally by a technician or non-physician health care professional.
  • External eye: standard digital stills or video camera
  • Anterior segment: slit lamp connected to a camera
  • Posterior segment or retina: fundus camera
Mydriasis may be required to obtain an image of sufficient quality. Stereoscopy may be used to detect retinal thickening.
The image can then be transferred, over the Internet or dedicated network to a physician for immediate examination, or for storage and later review. Ideally, the image is encrypted or anonymized for transmission, to protect patient confidentiality. Between image capture and viewing, image processing may be done, including compression, enhancement and edge-detection.
Image evaluation, to detect various pathologies in the case of asynchronous evaluation, is often done by an ophthalmologist, optometrist or primary care physician, though it is also performed by specially trained staff. Image evaluation may also be automated to provide pathology detection or grading.

Automated image recognition

Computer software applications have been tasked with the automated assessment of retinal images to recognize lesions associated with an ocular disease of interest. The clinical process entails initially discriminating retinal lesions from non-factor artifacts, subsequently distinguishing lesions associated with the disease in question from other types of lesions, and finally grading the disease according to guideline-endorsed severity scales set by medical authorities.
Dedicated research in artificial intelligence drives the underlying technology in automated image recognition. Specific approaches involve pattern recognition using trained artificial neural networks; feature extraction using edge-detection and region-growing techniques; and content-based comparison with previously adjudicated samples.

Advantages

  • Improved patient care
  • Strengthened referral patterns
  • Extended patient care and expertise to remote areas
  • Education of hospital staff, clinicians and the community
  • Cost-effectiveness
  • More effective planning and administrative meetings with point-and-click sharing of content
  • Use of videoconferencing to members of the human resources department has helped to resolve emergency staffing issues
  • Community nurses, ophthalmologists or optometrists in training can attend teaching sessions at the main hospital via a live video teleopthamological feed, thereby enhancing their knowledge and skills.

    Implemented projects by country

Australia

A 100-case audit of retinal screening by optometrists was performed in the remote areas of Western Australia. Projects are now being started base on this pilot experience.

Canada

A number of teleophthalmology programs exist in Canada, including those in the provinces of Alberta, British Columbia, Manitoba, Newfoundland, Ontario, and Quebec.
The cost of taking the images and of the ophthalmologist to interpret the images is covered by public-funded health care insurance. Typically a registered nurse or registered practical nurse is trained to dilate the patient's pupils and take the images.
Key challenges to providing teleophthalmology services in Canada are likely: 1) the high staff turnover in remote areas; 2) the lack of an inexpensive mobile imaging device that takes diagnostic quality images; and 3) the difficulty securing public funds where the costs are incurred and savings are realized from separate funding envelopes.

Alberta

Teleophthalmology has been provided in Alberta since 2003, and is supported by Alberta Health Services, using their proprietary teleophthalmology software . Approximately six ophthalmologists from the University of Alberta review the images. As of January 2014, approximately 15,000 patients had been screened for diabetic retinopathy, across 15 community-hospital-based stationary locations, 44 First Nations communities and five primary care practices. Approximately 130 patients are screened per month across these locations. The teleophthalmology program also facilitates approximately 55 optometrist-to-ophthalmologist referrals per month.

British Columbia

Teleophthalmology is provided by ophthalmologists from the University of British Columbia, and is supported by Alberta Health Service's proprietary software.

Manitoba

In Manitoba, teleophthalmology is provided by ophthalmologists at the University of Manitoba, and is supported using Alberta Health Service's proprietary software.

Newfoundland

A teleophthalmology program was started in the Eastern Health Region of Newfoundland, under one of four regional health authorities. This program was started in May 2012 and is supported by an ophthalmologist in St. John's. The program uses Synergy software by

Ontario

Thirteen teleophthalmology programs currently exist in Ontario. Two of the programs facilitate ophthalmology support for premature infants, screening for retinopathy of prematurity, using ophthalmologists at Sick Kids and McMaster University Medical Centre.
The other eleven of these teleophthalmology programs primarily screen for diabetic retinopathy in diabetic patients who have limited access to eye care professionals, or who for various reasons do not seek regular eye care. use the to transmit images to an ophthalmologist for evaluation. OTN uses teleophthalmology software to provide this service. Some of these locations use a fundus camera, others use both fundus and optical coherence tomography imaging devices, and all programs dilate their patients' eyes before screening. Since 2009, and as of January 2014, more than 4600 diabetic patients have been screened, finding pathology in approximately 25-35% of screens. Approximately 120 patients are screened per month, by five reading ophthalmologists.
In Ontario, the implementation of teleophthalmology has reduced the average wait time from six months to four weeks, for some diabetic patients to obtain retinal screening from a specialist.

China

Between 2006 and 2008, a large scale teleretinal screening project using mobile units was implemented in China.

France

The supports diabetic retinal screening across 34 sites and has screened over 13,000 patients since 2004.

India

The teleophthalmology program provided in Chennai, India by has reached more than 450,000 patients since its inception in October, 2003.
The , started in 2008, uses teleophthalmology to screen for retinopathy of prematurity. They are India's first, and the world's largest, program of this kind. They have performed more than 6339 imaging sessions of 1601 infants in rural and remote areas, preventing blindness and finding that non-physician experts can be trained to accurately grade the images.