10/9 - Seminar (NMR): Zoltán Takáts, Imperial College London
Zoltán Takáts - speaker's website
Reader in Medical Mass Spectrometry, Department of Surgery and Cancer
Imperial College London
Host: Istvan Pelczer
Mass Spectrometer in the Operating Theatre: Real-time Identification of Tissues by Shotgun Lipidomics
In-situ tissue identification is critically important during the surgical resection of the malignant tumors. Residual tumor tissue leads to rapid and aggressive recurrence, while damage to healthy tissue may result in loss of key physiological functions. Solution for the problem of in-situ tissue identification has been sought for decades, and a number of different solutions have been proposed including intraoperative medical imaging, in-vivo labeling of tumor tissue and various spectroscopic approaches including mass spectrometry (MS).
Direct MS analysis of tissue sections by various desorption ionization methods yields histologically specific data, which served as a basis for developing MS technologies for the in-vivo analysis of tissues. While existing DI methods were proven to be incompatible with the surgical environment, traditional surgical diathermy (electrosurgery) was discovered to work as an ion source by converting certain molecular components of tissue to gas-phase ions. The resulting method was termed ‘Rapid Evaporative Ionization MS’ referring to the critical nature of the rate of evaporation regarding ion formation. Since diathermy is used in surgery in the form of mono-polar/bipolar coagulation and cutting, standard electrosurgical instrumentation was coupled with mass spectrometry to obtain an analytical device capable of in-vivo, quasi real-time (time delay ~ 1 s) tissue characterization. The experimental setup was successfully tested ex-vivo, and multivariate statistical analysis of data revealed good histological specificity. The device has also been successfully tested in-vivo in a cohort of close to 500 patients with post-operative histological validation. The results revealed that most malignancies can easily be identified intraoperatively using REIMS technology and the approach combined with surgical navigation may provide a real alternative to currently used technologies. See the BBC's coverage of this new technology, dubbed "iKnife".