Purpose:
Currently, to obtain good quality ophthalmic images and to arrive at proper diagnosis, patient is obliged to visit a eye clinic or hospital with ophthalmic diagnostic tool which are far costly and require an extensive setup. Some of the diseases which can be diagnosed or suspected based on community based screening are cataracts, glaucoma, diabetic retinopathy, AMD. With this background, we propose:Aim 1: To develop a portable handheld camera system to acquire retinal images as a mass screening device.Aim 2: Low cost device compatible for mass screening & ease of use for ophthalmic retinal imaging and teleophthalmology.
Methods:
The image acquistion system is developed using off-the-shelf camera system but tailored to the specific requirements, incorporating lenses and light source for retina imaging. The invention is add-on device fitted to any current high resolution digital camera. It comprises a specially designed lens and illumination attachments as an adapter to a normal off-the-shelf camera.The Ophthalmic Camera System will ride on the PHIMS system that NTU have developed under the SUWA project for data flow, management and storage. The illumination system uses high brightness white light LEDs as the light source for the camera attachment. The circuit to control the brightness of the LED and the duration of strobe plays an important role to ensure sufficient amount of light is incident on the retina.
Results:
The portable device to connect to off the shelf camera system was designed and tested for proof of concept of image acquisition. Retinal images were acquired using the portable attachment. All the merits and demerits of the ophthalmic imaging system will be discussed in the paper.
Conclusions:
The hand held screening device can be useful tool to screen those diseases at doorstep of the individual. Risks involved non clear images in patients with media opacity and limited view of only central 30-45 degrees of fundus in non dilated pupil which may potentially lead to non capturing of retinal diseases in midperipheral and peripheral retina.
Clinical Trial:
www.research.nhg.com.sg, 2011/01731
Keywords: imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • imaging/image analysis: clinical • clinical (human) or epidemiologic studies: health care delivery/economics/manpower