biomedical precision engineering lab
DESCRIPTION
Author: Sakuma, I. Presentation for the Biomedical & Mechatronics Workshop Forum UTokyo USP, 2013TRANSCRIPT
Bio‐Medical Precision Engineering LabIchiro Sakuma, Estuko Kobayshi, Takehiro AndoSchool of Engineering, The University of Tokyo
• Computer Aided Surgery• Robotics for CAS• Electrophysiology of Arrhythmia
real time segmentation
5-ALA2.8μmicro-Laser
log
real time segmentation
5-ALA2.8μmicro-Laser
log
2.8μmicro-Laser
log
• 5‐Aminolevulinic Acid (5‐ALA) and Protoporphyrin IX (PpIX)
• 5‐ALA accumulates on tumors, and metabolizes to PpIX in malignant glioma.
• PpIX is a fluorescent substance; emits red fluorescence when it is excited by blue light.
5-ALA for intraoperative identification of malignant brain tumor
tumorbrain surface
5-ALA leads to intracellular accumulation of fluorescent prophyrins PpIX in malignant gliomas
PpIX
5-ALA
(Friesen et al, 2002)
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System configuration
Medical Image Analysis 16(3): 1361‐8415.
Laser ablation of porcine brain stained with 5‐ALA(Noguchi M., 2006)
Agar gel with intra‐lipid and Pp9(10[μg/ml])
• NEDO(New Energy and Industrial Technology Development Organization) “Intelligent Surgical Instrument Project”Sub‐project: Intelligent surgical instrument for minimally invasive thoracic surgery
• Periodic research meetings among researchers in clinical medicine, engineering, and industries
• Design modification through tests using prototypes in repeated workshops
http://www.nedo.go.jp/news/press/AA5_100145.htmlhttp://www.youtube.com/watch?v=aKdE8C8KcJI
Movie
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• Spiral is characterized by progressively increasing radius of curvature toward the center.
• Conduction velocity slows down toward the center because of progressive decrease of the source/sink ratio and eventually becomes zero.
• At the center, various phases of excitation meet and formulate singular point. The wavefront meets its own refractory tail and rotation persists around this pivot point.
Ventricular Tachycardia (VT), Ventricular fibrillation (VF)• Major cause of sudden cardiac death
• Reentrant excitation is one of the major cause of VT and VF
Optical Mapping of Cardiac Excitations
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Lig
ht I
nten
sity
Time
BackgroundComponent(F)
ΔF/F < 10%
Action PotentialAmplitude( F)Δ
Wavelength
Ligh
t stre
ngth Excitation
light
Resting
500 nm 600 nm
Excited
△F
Use of voltage sensitive dye: Di‐4‐ANEPPSSuppression of contraction by 2,3‐butandione monoxime(BDM)
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Application of visual feedback to eletctrical stimulation
High Speed
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