Cynthia Toth, MD, Principal Investigator
Cynthia Toth, MD is an authority in the development and research/clinical application of ophthalmic optical coherence tomography (OCT) with more than 25-years of translational research and over 80 publications in this field out of her 200 peer-reviewed publications. She has been an effective translational researcher in this field. She was director of the surgical instrument prototyping Biophysics Laboratory at Duke Eye Center before revamping this into the Duke Advanced Research in Swept Source/Spectral Domain OCT Imaging Laboratory in 2005, to focus on developing novel applications and analyses of OCT imaging for improvement of diagnosis and surgical and clinical treatment of eye disease in adults and children.
Dr. Toth was the first to associate vision loss in neovascular AMD with intraretinal cystoid edema rather than subretinal fluid, the first to take portable OCT to the bedside in the intensive care nursery and under research protocols to identify in the eyes of preterm infants: macular edema, its association with poor neurodevelopment, delay of photoreceptor development and nerve fiber layer thinning associated with brain abnormalities.
She has also been successful in collaboration with Joseph Izatt, Ph.D. in Biomedical Engineering for translation of novel OCT technology into neonatal and pediatric applications. She organized and lead a multidisciplinary translational OCT research team to study novel applications of portable ultra-compact swept-source OCT to view retinal microanatomy in retinopathy of prematurity and analyze relationships to visual pathway development and visual and neurodevelopmental outcomes (R01EY025009, Toth-PI).
Dr. Toth is also PI on an NIH CTSA-funded pilot study of non-dilated OCT of infants with hypoxic ischemic encephalopathy.
Research in Retinopathy of Prematurity (ROP)
Non-vascular aspects of ROP have received much less attention in the prevention of blindness, in large part because of the multitude of technical challenges in studying retinal pathologies in the small eyes of infants in a neonatal intensive care unit (NICU). Dr. Toth recognized a need and spearheaded bringing OCT technology to this population. Through a pilot grant from Duke’s Clinical Translational Science Award, she took a portable animal-research OCT system and developed methodology for use in bedside examination of awake infants. A refined version of the system was subsequently FDA cleared for infant imaging. In preterm infants Dr. Toth was the first to demonstrate the in vivo progress of subcellular retinal maturation, a delay in development of choroid and the optic nerve relative to term infants, a 3-dimensional rating system for retinal vascular abnormalities, and macular edema which had been previously unrecognized and is common in infants with ROP. This work has been highly collaborative and interdisciplinary, leading a team that includes biomedical engineers, neonatologists, neuroradiologists, child development specialists and pediatric ophthalmologists to investigate the developing eye-brain connection in premature infants. Our discoveries in preterm infants are leading us to a new era where bedside imaging with OCT in the NICU will aid in 1) early identification of infants at risk for neurodevelopmental and vision problems, and 2) monitoring the microanatomic response to interventions.
Intraoperative Applications of OCT Imaging
Collaborating with Joseph Izatt, PhD, Dr. Toth performed the seminal translational research in intraoperative OCT imaging. This spanned from her first-in-human use of portable OCT to image in surgery to our recent swept-source microscope-integrated OCT for the first real-time three-dimensional imaging of human ophthalmic surgery. Our multidisciplinary group also developed the first OCT stereoscopic heads-up display within the oculars of the operating microscope and other software to support the new field of ophthalmic image-guided surgery. Our team leads the world in intraoperative OCT imaging for eye surgery as demonstrated in my germinal publications from 2009 onward which established utility of intraoperative imaging to evaluate surgical endpoints, such as extent of removal of epiretinal membranes and associated tissue impact, viewing the retina around surgical instruments, using OCT feedback for trainees, and materials to optimize tissue appearance on OCT imaging in surgery.
Dr. Toth’s Laboratory, the Duke Advanced Research in Spectral Domain OCT Imaging (DARSI) Laboratory centers on improving early diagnostic methods, imaging biomarkers and therapies for both age-related macular degeneration (AMD) and for retinal diseases in children. In collaboration with Joseph Izatt, Ph.D. in Biomedical Engineering, the DARSI team is currently applying SD and SSOCT to the care of retinal diseases and especially in microsurgery in adults and in children in several studies including NIH funded investigations.