Impedimetric detection of whole blood concentration for early detection of intraocular hemorrhage

Early detection of retinopathy can substantially reduce the risk of visual impairment and blindness in diabetes mellitus (DM) patients. Screening tool such as Amsler grid may be useful for the early detection of maculopathy in DM patients, but the metamorphopsia by Amsler gird self-screening is subjectively, not objectively. Although some kinds of optical imaging instruments have been used for the early detection of retinopathy, self-testing regularly is still not possible. In this work, impedimetric detection of whole blood concentration is proposed to be a promising technique to detect intraocular hemorrhage. An intraocular implant chip is also discussed to integrate the impedimetric detection into a CMOS IC. Results revealed that the impedimetric measurement could indicate 5% (v/v) whole blood in intraocular irrigating solution. Such technique is a label-free, non-invasive, and real-time analytical method. The preliminary results showed that impedimetric measurement had high potential to be implemented to an intraocular implant chip.