1. BioMedicalPrecisionEngineeringLab IchiroSakuma,Estuko Kobayshi,Takehiro Ando SchoolofEngineering,TheUniversityofTokyo ComputerAidedSurgery RoboticsforCAS ElectrophysiologyofArrhythmiareal time segmentationlog 5-ALA 2.8micro-Laser

2. ALAforintraoperativeidentificationofmalignant braintumor 5AminolevulinicAcid(5ALA)and Protoporphyrin IX(PpIX) 5ALAaccumulatesontumors,and metabolizestoPpIX inmalignantglioma. PpIX isafluorescentsubstance; emitsredfluorescencewhenitis excitedbybluelight.tumorbrain surface5-ALAPpIX(Friesen et al, 2002) 5-ALA leads to intracellular accumulation of fluorescent prophyrins PpIX in malignant gliomas 3. SystemconfigurationMedicalImageAnalysis16(3):13618415.3 4. Laserablationofporcinebrainstainedwith5ALA (NoguchiM.,2006)Agargelwithintralipid andPp9(10[g/ml]) 5. NEDO(NewEnergyandIndustrialTechnologyDevelopment Organization)IntelligentSurgicalInstrumentProject Subproject:Intelligentsurgicalinstrumentforminimally invasivethoracicsurgery Periodicresearchmeetingsamongresearchersinclinical medicine,engineering,andindustries Designmodificationthroughtestsusingprototypesinrepeated workshopshttp://www.nedo.go.jp/news/press/AA5_100145.html http://www.youtube.com/watch?v=aKdE8C8KcJI 6. Movie 7. Ventricular Tachycardia (VT), Ventricular fibrillation VF) Major cause of sudden cardiac death Reentrant excitation is one of the major cause of VT and VF 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. 7 8. Excitation lightExcitedRestingF500 nm600 nmWave lengthLight IntensityLight strengthOpticalMappingofCardiacExcitationsBackground Component(F) Action Potential Amplitude( F) F/F < 10%Useofvoltagesensitivedye:Di4ANEPPS Suppressionofcontractionby2,3butandionemonoxime(BDM)8Time 9. Application of visual feedback to eletctrical stimulationHighSpeed9 10. 10