Ian Couper

A simple telemedicine system using a digital camera

Radiographs on a viewing box were photographed at a remote hospital in South Africa using a digital camera with a resolution of 1024x768 pixels at 24-bit colour depth. The resultant images were stored in JPEG format and transmitted as email attachments to be read on a PC monitor by radiologists in Durban and Cape Town. Twenty-seven images were received, of which 23 were of diagnostic quality (85%). The mean file size was 120 kByte. For quality control purposes, 100 chest radiographs were photographed at a base hospital and read by a radiologist blinded to the diagnosis. In this study 96 images were of diagnostic quality (96%) and the correct diagnosis was made in 90 cases (94%). Incorrect readings were made in six cases (6%): small pulmonary nodules (less than 1 cm in diameter) were missed in five cases and in one case early apical tuberculosis was missed. Digital camera technology permits simple, inexpensive telemedicine. Limited spatial resolution is a concern when reading chest images with small pulmonary nodules and infiltrates.