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Targeting and Safety Monitoring for LIFUP in First Human Trials. Alexander Korb, PhD Mentor: Alexander Bystritsky, M.D., Ph.D. Objective. Develop a non-invasive neuromodulation system that can safely and accurately target the hypothalamus. ) ) ) ) ). Transducer. Outline. Background
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Targeting and Safety Monitoring for LIFUP in First Human Trials Alexander Korb, PhD Mentor: Alexander Bystritsky, M.D., Ph.D
Objective Develop a non-invasive neuromodulation system that can safely and accurately target the hypothalamus )))) ) Transducer
Outline • Background • Technology • Experiments • Next Steps
Background • Hypothalamus • Target for insulin • Center for appetite and satiety • Deep Brain Stimulation (DBS) of lateral hypothalamus • Weight loss in rats • Indirect results in humans show potential • Obici et al, 2002; Bernardis and Bellinger, 1996; Halpern et al, 2008; Sani et al, 2007; Torres et al 2011
DBS = X
Alternative to DBS • Low-Intensity Ultrasound Pulsations (LIFUP) • Highly focused • Non-invasive • Safe ) ) ) ) )
Outline • Background • Technology • Experiments • Next Steps
Ultrasound • Traditional US Imaging • Reflect acoustic energy • Focused US • Absorb acoustic energy • Increased intensity to a small region ) ) ) ) ) ) ) ) ) ) Transducer ) ) ) ) ) Transducer
LIFUP Neuromodulation • Hippocampal excitation • Motor activation • Suppression of visual response • Suppression of seizure activity Tyler et al, 2008; Tufail et al 2010; Min et al, 2011; Yoo et al, 2011
Challenges for Human LIFUP • Skull absorbs energy • Skull changes shape of beam focus • Skull changes location of beam focus • Invisible beam X Ultrasound
Goals of Experiments • Assess feasibility • Develop targeting • Test safety
Outline • Background • Technology • Experiments • Next Steps
Feasibility in Large Mammalian Brain • Anesthetized mini-pig • Prepared skull • Targeted hypothalamus with stereotactic frame ) ) ) Mulgaonkar et al 2012
Targeting with Thermometry • Continuous US to cause heating • Proton resonant frequency is proportional to temperature 9cm 20s 40s 60s 80s 100s 120s 140s 160s Δ0.36°C Δ0°C FUS ON 9cm FUS OFF
Skull Heating During LIFUP • Near FDA limit for diagnostic US • Only mild heating even after 5 minutes
Skull Heating During CW US • 60s of continuous US • 13.4W/cm2 Ispta
Goals of Experiments • Assess feasibility • Develop targeting • Test safety ✓ ✓ ✓
Conclusions • LIFUP can accomplish neuromodulation in deep brain structures • MR-Thermometry can be used for targeting • LIFUP is ready for human testing
Outline • Background • Technology • Experiments • Next Steps
First Human Experiments • 10 patients with temporal lobe epilepsy • Concurrent LIFUP and fMRI • Outcomes: • Absence of histological damage • Neuromodulation • Changes in epileptic activity • Changes in seizure frequency
Thank You Thanks to the Friedman Diabetes Institute for their generous support of this project