The purpose of this study was to test the suitability of three available camera technologies (desktop, portable, and iphone
based) for imaging comatose children who presented with clinical symptoms of malaria. Ultimately, the results of
the project would form the basis for a design of a future camera to screen for malaria retinopathy (MR) in a resource
challenged environment. The desktop, portable, and i-phone based cameras were represented by the Topcon, Pictor Plus,
and Peek cameras, respectively. These cameras were tested on N=23 children presenting with symptoms of cerebral
malaria (CM) at a malaria clinic, Queen Elizabeth Teaching Hospital in Malawi, Africa. Each patient was dilated for
binocular indirect ophthalmoscopy (BIO) exam by an ophthalmologist followed by imaging with all three cameras. Each
of the cases was graded according to an internationally established protocol and compared to the BIO as the clinical
ground truth. The reader used three principal retinal lesions as markers for MR: hemorrhages, retinal whitening, and
vessel discoloration.
The study found that the mid-priced Pictor Plus hand-held camera performed considerably better than the lower price
mobile phone-based camera, and slightly the higher priced table top camera. When comparing the readings of digital
images against the clinical reference standard (BIO), the Pictor Plus camera had sensitivity and specificity for MR of
100% and 87%, respectively. This compares to a sensitivity and specificity of 87% and 75% for the i-phone based
camera and 100% and 75% for the desktop camera. The drawback of all the cameras were their limited field of view
which did not allow complete view of the periphery where vessel discoloration occurs most frequently. The consequence
was that vessel discoloration was not addressed in this study. None of the cameras offered real-time image quality
assessment to ensure high quality images to afford the best possible opportunity for reading by a remotely located
specialist.
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