Fiber Tractography Lab

The Fiber Tractography Lab is dedicated to the development of novel numerical methods that map brain connections and improve the clinical treatment of brain diseases.

We adapted principled approaches to understanding structural characteristics of white matter bundles, resolving their associations with measures of cognition, and developing accurate diagnostic/prognostic models that predict brain disorders.

Mapping Brain Connections

Diffusion MRI has arisen as the only non-invasive way to map white matter bundles and assess their structural integrity in the human brain. With fast imaging sequences, diffusion MRI, in particular its high angular resolution variants, can be acquired on standard clinical scanners. This advancement has gained considerable interest because of its roles in mapping human connectome and potential for accessing neuropsychological disorders. There is a growing interest in large-scale analysis of diffusion MRI to explore its promising applications in biomedical research as an imaging biomarker of neuropathology.

We developed a high-accuracy fiber tracking method powered by generalized q-sampling imaging (Yeh et al., 2010) and its derived tracking method (Yeh et al., 2013). The method was released as an open-source tool to the public known as “DSI Studio” (http://dsi-studio.labsolver.org). This fiber tracking method is a long-term collaborative effort between diffusion MRI radiologists, psychologists, and neurosurgeons (Fernandez-Miranda et al., 2012; Yeh et al., 2013b; Yeh et al., 2010). The approach was previously optimized using capillary phantoms and validated by experienced neurosurgeons (Yeh et al., 2013b), leading to its outperformance over other competing algorithms.

Left: DSI Studio tractography on the cover of “Nature Reviews Neurology” for the whole year of 2017. About the cover. Brains and beauty — the 2017 cover. Nat Rev Neurol 13, 1 (2017)

Translational Research in Clinical Applications

Under the research projects, our research tool has helped more than 200 brain tumor patients at the University of Pittsburgh Medical Center:

Patient’s story: 1, 2, 3

Fiber tracking in DSI Studio provides a superior presurgical evaluation of the fiber tracts for patients with complex brain lesions, including low-grade and high-grade gliomas. Presurgical studies are built upon precise and accurate neuroanatomical knowledge, which allows doctors to reconstruct perilesional or intralesional fiber tracts, design the less invasive trajectory into the target lesion and apply more effectively intraoperative electrical mapping techniques for maximal and safe tumor resection in eloquent cortical and subcortical regions.

Our clinical experience applying DSI Studio fiber tracking has been reported in Neurosurgery, Journal of Neurosurgery, and Neuro-oncology among others. We are actively investigating its potential for not only presurgical planning and intraoperative navigation but also for neurostructural damage assessment, estimation of postsurgical neural pathways damage and recovery, and tracking of postsurgical changes and responses to rehabilitation therapy. The latest innovation is the reconstruction of cranial nerves for presurgical evaluation in skull base surgery, with very promising results. The ultimate goal is to facilitate brain function preservation and recovery in patients undergoing complex brain surgery.

From a clinical perspective, our tracking method provides accurate structural connectivity studies in patients with intracerebral lesions (Abhinav et al., 2014b; Fernandez-Miranda et al., 2012; Yeh et al., 2013a) with other numerous applications in neurological and psychiatric disorders (see more than 200 journal publications in the last three years using DSI Studio, allowing for qualitative and quantitative white matter damage assessment, aiding in understanding lesion patterns of white matter structural injury, and facilitating innovative neurological and psychiatric applications. We conducted several studies to show that our tracking approach correlates well with histology (Gangolli et al., 2017; Modo et al., 2016) and cadaver microdissection in mapping several fiber pathways (Fernandez-Miranda et al., 2012; Fernandez-Miranda et al., 2014; Meola et al., 2016a; Meola et al., 2015; Meola et al., 2016b; Wang et al., 2016; Wang et al., 2013; Yoshino et al., 2016) and is a major improvement over DTI tractography (Abhinav et al., 2014a; Abhinav et al., 2014c; Abhinav et al., 2014d; Yeh et al., 2013b).

Contact

Fang-Cheng (Frank) Yeh

frank.yeh@pitt.edu

Department of Neurological Surgery

UPMC Presbyterian, Suite B-400

200 Lothrop Street

Pittsburgh, PA 15213