Novel system for improved aiming during optical coherence tomography imaging of young children
When a retinal condition is suspected in a patient, optical coherence tomography (OCT) is used to obtain detailed images of the retina. Due to the large amount of data needed to be processed during image acquisition, several seconds are needed to collect sufficient data. During this time patient needs to fix their gaze so that the OCT system is centered on fovea (most sensitive and critical retinal region). While looking in one direction and concentrating on one point for several seconds is usually not an issue for adults and older children, infants and active toddlers would not cooperate. In that case the choices usually are to place a child under general anesthesia (which involves many risks), perform a limited examination or wait until the child grows older and is able to cooperate. For that reason, some treatable retinal conditions in young children are frequently missed, which creates a need for a technology allowing detecting and tracking eye fixation and synchronizing it with OCT system focus.
Duke researchers present a novel system that combines OCT imaging with a retinal birefringence scanning (RBS). During RBS, a spot of near infrared polarized light is scanned in a circle on the retina. Foveal fixation (when the patient is looking at the center of the scanned circle) is determined from the polarization signature or the light reflected back. RBS allows fast, direct and reliable eye-focus detection that has been demonstrated in adults and has been used for diagnosing strabismus in young children. In the Duke’s design, the RBS-subsystem detects and signals the presence of foveal fixation to the OCT subsystem, thus triggering data collection. Throughout the examination, the unsuspecting child is viewing a cartoon on a small LCD computer screen, which specific attention/fixation locking targets appearing periodically in the center of the screen while the main movie fades away. The examiner is thus able to retain optical alignment of the OCT device with the child’s eye.
- Allows diagnosis of retinal diseases in young or patients and in other patients who cannot cooperate with traditional OCT exams
- Allows monitoring of the progression or response to ocular therapy without a need for sedation or anesthesia
- Clinically suitable