Mii ret cam

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Jul 21, 2015 - adapter, and smartphone (with built-in flashlight and camera). Imaging technique. The user holds the device equipped with a smartphone.
EJO ISSN 1120-6721

Eur J Ophthalmol 2015; 00 (00): 000-000 DOI: 10.5301/ejo.5000663

Original Article

Smartphone-based fundus camera device (MII Ret Cam) and technique with ability to image peripheral retina Ashish Sharma1, Saranya Devi Subramaniam2, KI Ramachandran2, Chinnasamy Lakshmikanthan2, Soujanya Krishna1, Selva K. Sundaramoorthy1 1 2

Lotus Eye Hospital and Institute, Coimbatore, Tamilnadu - India Amrita School of Engineering, Amrita Vishwa Vidyapeetham, Coimbatore, Tamilnadu - India

Abstract Purpose: To demonstrate an inexpensive smartphone-based fundus camera device (MII Ret Cam) and technique with ability to capture peripheral retinal pictures. Methods: A fundus camera was designed in the form of a device that has slots to fit a smartphone (built-in camera and flash) and 20-D lens. With the help of the device and an innovative imaging technique, high-quality fundus videos were taken with easy extraction of images. Results: The MII Ret Cam and innovative imaging technique was able to capture high-quality images of peripheral retina such as ora serrata and pars plana apart from central fundus pictures. Conclusions: Our smartphone-based fundus camera can help clinicians to monitor diseases affecting both central and peripheral retina. It can help patients understand their disease and clinicians convincing their patients regarding need of treatment especially in cases of peripheral lesions. Imaging peripheral retina has not been demonstrated in existing smartphone-based fundus imaging techniques. The device can also be an inexpensive tool for mass screening. Keywords: MII Ret Cam, Peripheral retina, Smartphone-based fundus imaging

Introduction The smartphone has revolutionized fundus imaging, starting with capturing images with the smartphone and slit-lamp (1-4). Researchers have been successful in creating indirect smartphone-based devices and techniques with the ability to image limited areas of the fundus (5-7). Previous researchers from the developed world made an effort to help developing countries by exploring a mass screening tool in the form of a smartphone-based indirect fundus camera. Our group, practicing in India, a developing country, realized a much wider need for a smartphone-based, inexpensive, portable device, which could be capable of imaging central and peripheral retina. In India, many retina practitioners and comprehensive ophthalmology practitioners find it difficult to afford fundus cameras at the beginning of their practice. There are multiple solo clinics across the country and due to unaffordability of fundus cameras, diagnosis and documentation of retinal pathologies may be neglected. This affects the overall quality of ophthalmic care across the country. Accepted: July 21, 2015 Published online: Corresponding author: Ashish Sharma Lotus Eye Hospital and Institute Coimbatore, Tamilnadu, India [email protected]

© 2015 Wichtig Publishing

We designed a device and imaging technique that can image regions of the peripheral-most retina such as ora serrata and further to the pars plana apart from the central fundus. To the best of our knowledge, this is the first smartphone based device and technique available with the ability to image the entire fundus, central and peripheral.

Materials and methods The device (Fig. 1A) consists of a 20-D lens, MII Ret Cam adapter, and smartphone (with built-in flashlight and camera). Imaging technique The user holds the device equipped with a smartphone and 20-D lens as shown in Figure 1, B and C. For central fundus imaging, the user holds the device close to the eye and once fundus glow is visualized through the dilated pupil, slowly brings it back (similar to standard indirect ophthalmoscopy) until a clear image can be visualized in the smartphone camera (Fig. 1B). For peripheral imaging, the user holds the indenter in the hand that he or she normally uses during indirect ophthalmoscopy and tries to indent the area of interest and follow a similar focusing technique as described previously (Fig. 1C). High-quality video films of the central and peripheral fundus can be obtained from the smartphone. For still images to be given in an electronic format or as a printout to patients, the user can browse the video, freeze the video

Smartphone-based fundus camera

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Fig. 1 - (A) MII Ret Cam Device. (B) Position of MII Ret Cam during central fundus imaging. (C) One hand holding MII Ret Cam while the other hand is used for indentation for peripheral imaging.

at the desired image, and take a snapshot. Snapshots are saved as individual images that are easy to transfer electronically and to print.

Results Results are illustrated in Figure 2.

Discussion Several authors have described smartphone-based fundus imaging but none of them demonstrated the ability to capture peripheral images (1-6). The technique described by Haddock et al (5) and Bastawrous (6) requires one hand to support the 20-D lens and other hand to hold the smartphone; hence there is no hand available for indentation. Myung et al (7) did not explore the possibility of peripheral imaging. Our device and technique allows clinicians to have one hand free for indentation. This method helps to capture high-quality peripheral images. We performed a pilot study by training 2 of our first-year residents who were not exposed to any kind of funduscopy previously for 1 month. One was trained in traditional indirect ophthalmoscopy and other was trained in smartphone-based indirect ophthalmoscopy. The resident who was trained in smartphone-based indirect ophthalmoscopy found it easier to identify lesions at both the central and peripheral fundus compared to the resident trained in traditional indirect ophthalmoscopy. The lesion detection rate was higher in the resident trained in smartphone-based

Fig. 2 - (A) Diabetic retinopathy central fundus in grade II cataract. (B) Diabetic retinopathy midperipheral fundus in grade II cataract. (C) Lattice with hole post barrage laser shows ora and pars plana (arrow). (D) Snowballs (arrow) with 2+ vitritis.

ophthalmoscopy compared to the resident trained in traditional indirect ophthalmoscopy (unpublished data). The ability to image the central and peripheral retina easily and inexpensively can assist in practicing evidencebased medicine by demonstration of peripheral lesions to patients; monitoring disease and treatment response in cases of uveitis and possibly retinopathy of prematurity, HIV retinopathy, and ocular tumors; use in bedridden patients; use in multiple clinics covered by clinicians; mass screening for diabetic retinopathy; and teaching by demonstration rather than theoretical description. We are working on advancements in the existing device design and technique along with the release of the first device.

Abbreviation MII Ret Cam  Make In India Retinal Camera

Acknowledgment The name of the device was adapted to support the vision of Make In India (MII) by Prime Minister Narendra Modi.

Disclosures Financial support: No financial support was received for this submission. Conflict of interest: None of the authors has conflict of interest with this submission. Device is patent pending.

© 2015 Wichtig Publishing

Sharma et al

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