Hedok Lee
Stony Brook University
Publications 39
The accumulation of fibrillar amyloid β-protein (Aβ) in blood vessels of the brain, the condition known as cerebral amyloid angiopathy (CAA), is a common small vessel disease that promotes cognitive impairment and is strongly associated with Alzheimer’s disease. Presently, the clinical diagnosis of this condition relies on neuroimaging markers largely associated with cerebral macro/microbleeds. However, these are markers of late-stage disease detected after extensive cerebral vascular amyloid ac...
#1Rena ElkinH-Index: 2
#2Saad NadeemH-Index: 4
Last.Allen TannenbaumH-Index: 60
view all 5 authors...
In this work, a unified representation of all the time-varying dynamics is accomplished with a Lagrangian framework for analyzing regularized dynamical optimal mass transport (OMT) derived flows. Our Lagrangian framework is also applicable to the Fisher-Rao regularization because, as we show, it is equivalent to our regularized dynamical OMT formulation. The advantage of the Lagrangian framework is that the time-varying trajectories and particle attributes are displayed in a single visualization...
Sep 16, 2018 in MICCAI (Medical Image Computing and Computer-Assisted Intervention)
#1Rena Elkin (SBU: Stony Brook University)H-Index: 2
#2Saad Nadeem (MSK: Memorial Sloan Kettering Cancer Center)H-Index: 4
Last.Allen Tannenbaum (SBU: Stony Brook University)H-Index: 60
view all 7 authors...
The glymphatic system (GS) is a transit passage that facilitates brain metabolic waste removal and its dysfunction has been associated with neurodegenerative diseases such as Alzheimer’s disease. The GS has been studied by acquiring temporal contrast enhanced magnetic resonance imaging (MRI) sequences of a rodent brain, and tracking the cerebrospinal fluid injected contrast agent as it flows through the GS. We present here a novel visualization framework, GlymphVIS, which uses regularized optima...
3 CitationsSource
#1Rany MakaryusH-Index: 6
#2Hedok LeeH-Index: 15
Last.Helene BenvenisteH-Index: 38
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BACKGROUND:Potential deleterious effect of multiple anesthesia exposures on the developing brain remains a clinical concern. We hypothesized that multiple neonatal anesthesia exposures are more detrimental to brain maturation than an equivalent single exposure, with more pronounced long-term behavioral consequences. We designed a translational approach using proton magnetic resonance spectroscopy in rodents, noninvasively tracking the neuronal marker N-acetyl-aspartate, in addition to tracking b...
2 CitationsSource
#1Helene BenvenisteH-Index: 38
#2Hedok LeeH-Index: 15
Last.Hanbing LuH-Index: 17
view all 9 authors...
The glymphatic pathway transports cerebrospinal fluid through the brain, thereby facilitating waste removal. A unique aspect of this pathway is that its function depends on the state of consciousness of the brain and is associated with norepinephrine activity. A current view is that all anesthetics will increase glymphatic transport by inducing unconsciousness. This view implies that the effect of anesthetics on glymphatic transport should be independent of their mechanism of action, as long as ...
23 CitationsSource
#1Vadim Ratner (SBU: Stony Brook University)H-Index: 3
#2Yi Gao (SBU: Stony Brook University)H-Index: 14
Last.Allen Tannenbaum (SBU: Stony Brook University)H-Index: 60
view all 6 authors...
It was recently shown that the brain-wide cerebrospinal fluid (CSF) and interstitial fluid exchange system designated the `glymphatic pathway' plays a key role in removing waste products from the brain, similarly to the lymphatic system in other body organs [1,2]. It is therefore important to study the flow patterns of glymphatic transport through the live brain in order to better understand its functionality in normal and pathological states. Unlike blood, the CSF does not flow rapidly through ...
3 CitationsSource
#1Anders Jørgensen (UCPH: University of Copenhagen)H-Index: 4
#2Pke Magnusson (Copenhagen University Hospital)H-Index: 87
Last.Martin Balslev Jørgensen (UCPH: University of Copenhagen)H-Index: 26
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Objective To investigate the role of hippocampal plasticity in the antidepressant effect of electroconvulsive therapy (ECT). Method We used magnetic resonance (MR) imaging including diffusion tensor imaging (DTI) and proton MR spectroscopy (1H-MRS) to investigate hippocampal volume, diffusivity, and metabolite changes in 19 patients receiving ECT for severe depression. Other regions of interest included the amygdala, dorsolateral prefrontal cortex (DLPFC), orbitofrontal cortex, and hypothalamus....
34 CitationsSource
#1Rany MakaryusH-Index: 6
#2Hedok LeeH-Index: 15
Last.Helene BenvenisteH-Index: 38
view all 7 authors...
BACKGROUND: A wealth of data shows neuronal demise after general anesthesia in the very young rodent brain. Herein, the authors apply proton magnetic resonance spectroscopy (1HMRS), testing the hypothesis that neurotoxic exposure during peak synaptogenesis can be tracked via changes in neuronal metabolites. METHODS: 1HMRS spectra were acquired in the brain (thalamus) of neonatal rat pups 24 and 48 h after sevoflurane exposure on postnatal day (PND) 7 and 15 and in unexposed, sham controls. A rep...
14 CitationsSource
#1Hedok LeeH-Index: 15
#2Lulu Xie (UR: University of Rochester)H-Index: 5
Last.Helene BenvenisteH-Index: 38
view all 8 authors...
The glymphatic pathway expedites clearance of waste, including soluble amyloid β (Aβ) from the brain. Transport through this pathway is controlled by the brain's arousal level because, during sleep or anesthesia, the brain's interstitial space volume expands (compared with wakefulness), resulting in faster waste removal. Humans, as well as animals, exhibit different body postures during sleep, which may also affect waste removal. Therefore, not only the level of consciousness, but also body post...
77 CitationsSource
#1Oren S. Cohen (TAU: Tel Aviv University)H-Index: 19
#2Joab Chapman (TAU: Tel Aviv University)H-Index: 42
Last.Hedok Lee (SBU: Stony Brook University)H-Index: 15
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Familial Creutzfeldt–Jakob disease (fCJD) in Jews of Libyan ancestry is caused by an E200K mutation in the PRNP gene. While carriers are born with this mutation, they usually remain asymptomatic until middle age. Early detection of conversion is crucial for understanding and eventually for the treatment of the disease. The aim of this study was to report longitudinal MRI data in E200K individuals who eventually converted from healthy mutation carriers to clinically symptomatic CJD. As a part of ...
6 CitationsSource