About Me

Biomedical Engineering

Designing non-invasive optical neuromonitoring technologies to guide pediatric critical care.

The focus of my research is the development of non-invasive optical tools to identify critical periods of neurological vulnerability and to direct individualized clinical management to mitigate neurological injury in critically-ill children. Currently, I am a Research Scientist in the Children’s Hospital of Philadelphia (CHOP) Resuscitation Science Center. I specialize in the development and validation of real-time, brain-directed interventional management strategies in preclinical pediatric swine models of cardiopulmonary resuscitation and extracorporeal life support.

Working in collaboration with clinician/scientists in the CHOP Resuscitation Science Center and the Department of Biomedical and Health Informatics, I lead data architecture, integration and machine learning model development efforts to examine this rich physiologic dataset (high-resolution physiologic waveforms, blood gas and serum biomarkers, brain MRI, metabolomics, mitochondrial respirometry, histopathology) to identify novel physiologic predictors of survival and neurological injury.

Thank you for visiting and please do not hesitate to get in touch!

A green and brown rural landscape leading into a bright blue ocean and slightly cloudy sky, done in oil paints.

Research Topics

Diffuse Optical Monitoring of Tissue Hemodynamics and Metabolism

Towards individualized neuroprotective strategies.

Congenital Heart Defects (CHD)

Perioperative Monitoring of Cerebral Hemodynamics

Infants with critical congenital heart disease (CHD) experience a high incidence of neurological injury, specifically diffuse white matter injury, which may underlie adverse neurodevelopmental outcomes at school age. Using non­invasive diffuse optical measurements of cerebral hemodynamics, we have uncovered an important link between time­-to-­surgery, declining cerebral oxygen saturation, and risk of new or worsened post­operative white matter injury. This work aims to elucidate the peri­operative timing of cerebral metabolism and desaturation to pinpoint vulnerable periods for injury.
Read more in our 2018 publication on preoperative cerebral hemodynamics.

Validation Study [Preclinical]

Cerebral Oxygen Metabolism During Deep Hypothermic Cardiopulmonary Bypass

Deep hypothermic cardiopulmonary bypass (DH CPB) is an important, neuroprotective strategy wherein the patient is cooled below 20˚C via cardiopulmonary bypass (CPB) to stabilize cerebral metabolism. This typically occurs in infants and children undergoing surgical repair of complex congenital heart disease (CHD). Despite widespread use over four decades, uncertainty remains per the optimal temperature management for cooling and rewarming to prevent hypoxic-ischemic-reperfusion brain injury. Validation of non-invasive diffuse optical measurement of cerebral oxygen metabolism may enable individualized optimization of management protocols which ensure sufficient metabolic suppression. In my work, continuous, non-invasive frequency-domain diffuse optical spectroscopy (FD-DOS) and diffuse correlation spectroscopy (DCS) measurements of cerebral oxygen metabolism and cerebral blood flow are validated against invasive measurements of cerebral oxygen extraction and perfusion in a piglet model of DH CPB.
Read more in our 2018 publication.

Injury Mechanisms [Preclinical]

The Impact of Deep Hypothermic Circulatory Arrest (DHCA) on Cerebral Hemodynamics and Metabolism

Building off the DH CPB validation study, the present study characterizes the incremental impact of deep hypothermia and of circulatory arrest on cerebral oxygen metabolism measured using hybrid FD-DOS/DCS in a neonatal swine model of cardiac surgery. This work will provide improved understanding of the contributing factors to cerebral metabolic vulnerability during DHCA in children.

Physiologic-Directed Resuscitation [Preclinical]

Determining the Association of Cerebral Hemodynamics during CPR and Recovery of the Heart

Respiratory-mediated cardiac arrest affects thousands of children each year in the United States.more then 50% of children will not survive to discharge after such an event, and most survivors often have significant neurological injury. The lack of standardized neuromonitoring during resuscitation has precluded the use of cerebral diagnostics to guide CPR and optimize neurological outcomes. This study will provide valuable data to demonstrate the utility of non-invasive diffuse optical neuromonitoring in reflecting the real-time neurophysiology during resuscitation.

Pregnancy Monitoring

Non-Invasive Transabdominal Measurement of Placental Oxygenation during Pregnancy

Robust transport of oxygen across the placental bed is essential to healthy fetal maturation. Aberrant placental oxygenations have been reported in intra-uterine growth restriction (IUGR), pregnancy-induced hypertension (PIH) and other gestational complications based on non-invasive, transabdominal oximetry using continuous-wave near-infrared spectroscopy (CW-NIRS). These findings are limited in sample size and exhibit high inter-subject variability attributed to the uncertainties of placental and superficial tissue morphology with respect to the measurement location, and tissue optical property assumptions utilized in CW-NIRS. Employing radio frequency (RF) modulated light, advanced frequency-domain near-infrared spectroscopy (FD-NIRS) permits patient-specific characterization of optical properties thereby reducing variability and improving physiologic accuracy. In this work, we are currently using ultrasound-guided FD-NIRS to quantify placental oxygenation in healthy mothers



Looking forward to connecting with you.

If you would like to get in touch, feel free to fill out the form below or email me directly at tiko@seas.upenn.edu.