Marco Bettiol

Dottore

ciclo: XXXIV


tutor: prof. Roberto Pani

Titolo della tesi: Body K-Tomography

The biological issue addressed The potassium (K) monitoring is crucial to diagnose the serious manifestations of hypokalemia and hyperkalaemia, which can involve several diseases, often life-threatening, such as muscle weakness or paralysis, cardiac conduction abnormalities or arrhythmias. Covid-19 has recently been found to cause hypokalemia, too. Unfortunately, the currently available methods for K monitoring are based on in vitro measurements, and so a real-time monitoring is not allowed. Herein the first non-invasive wearable detector, which measures in vivo potassium, is proposed. It uses the intrinsic radioactivity of one K isotope, the 40K, in equilibrium with stable isotopes 39K and 41K. Therefore neither invasive nor additional radiation are needed, only the one already present in human body. Moreover, it performs a direct in-vivo measurement on intracellular K, ensuring a higher accuracy and allowing a continuous monitoring of patient potassium, remotely too. Results The proposed detector is composed by five NaI scintillators (diameter 2.5cm, length 10cm) optionally coupled to 5 Silicon Photo Multiplier arrays. A feasibility study of such detector, placed close to human liver, was carried out. First, the radiation background was estimated, both with theoretical evaluation (520 gamma/s) and with experimental measurements (220 gamma/s). Then, detection and geometrical efficiency were assessed. The geometrical efficiency estimation was obtained with the computational human phantoms (also known as voxel phantoms), from CTs of real patients. In the CT images of these patients, the segmentation of organs with not negligible potassium amount was carried out. With a statistical method, based on the isotropic generation of 1k gamma events and on the count of photons impinging on the detector, it was possible to assess geometrical efficiency. The detector position relative to patient was finally selected, in order to maximize geometrical efficiency. The overall efficiency resulted 0.2%. The comparison of the amount of K used for detection, between the proposed method and the standard method based on the blood sampling, was reported. In the first case the detector gets information from 8.3g of K, mainly present in the liver and in muscles, which lead to a concentration of 0.54 mg of K per Kg, taking into account the detector efficiency. In the latter case, the information comes from the sample (5ml) of serum, where the K concentration is 120 mg/l. Assuming a 100% efficiency, the K used in this electrochemical measurement is 0.6mg. Since the project goal is the early hypokalemia diagnosis, as required for the quick treatment of the covid patient, the detector has been tested for the detection of pathological potassium reduction (for moderate hypokalemia the reduction is above 25%). To test the discrimination between the measurements with and without K reduction, the parametric Z test was used. The minimum detectable activity as a function of measuring time, pathological potassium reduction and confidence level has finally been obtained. Conclusions Herein a proposal of the first non invasive wearable in vivo intracelullar potassium measuring detector is reported. It has been designed overcoming many experimental challenges, first of all low counts 40K activity, thanks to a trade off for several problems as cheapness, weight and signal (human 40K radioactive emissions) to noise (background radiation) ratio. It will be particularly useful for territorial health structures, because they will be able to monitor the bedridden patient from their home. Costly and unnecessary mass hospitalizations will therefore be avoided.

Produzione scientifica

  • 11573/856753 - 2015 - A Novel Method for Y Photons Depth of Interaction Discrimination on Monolithic LYSO Crystals for Brain PET/MRI (04f Poster)
    PANI, ROBERTO; BETTIOL, MARCO; BORRAZZO, CRISTIAN; PELLEGRINI, ROSANNA; FABBRI, ANDREA; DI CASTRO, ELISABETTA
  • 11573/874836 - in press - A Novel Method for γ-photons Depth-of-Interaction Detection in Monolithic Scintillation Crystals (01a Articolo in rivista)
    PANI, ROBERTO; BETTIOL, MARCO; BORRAZZO, CRISTIAN; PELLEGRINI, ROSANNA; CINTI, MARIA NERINA; FABBRI, ANDREA; DI CASTRO, ELISABETTA
  • 11573/1071394 - 2014 - A novel brain PET insert for the MINDView project (01a Articolo in rivista)
    PANI, ROBERTO; BETTIOL, MARCO
  • 11573/1071461 - 2017 - Performance evaluation of the MindView PET using GATE and STIR (04b Atto di convegno in volume)
    PREZIOSI, ENRICO; BORRAZZO, CRISTIAN; BETTIOL, MARCO; PANI, ROBERTO
  • 11573/1071359 - 2016 - The MINDView brain PET detector, feasibility study based on SiPM arrays (01a Articolo in rivista)
    PANI, ROBERTO; BETTIOL, MARCO
  • 11573/1071460 - 2017 - PET and MRI-guided focused ultrasound surgery for neurological applications (04b Atto di convegno in volume)
    BORRAZZO, CRISTIAN; PREZIOSI, ENRICO; BETTIOL, MARCO; DI CASTRO, ELISABETTA; BENNATI, PAOLO; NAPOLI, ALESSANDRO; PELLEGRINI, ROSANNA; PANI, ROBERTO
  • 11573/1071458 - 2017 - Monte carlo simulation to evaluate factors affecting imaging performances of compact scintillation gamma camer (04b Atto di convegno in volume)
    BORRAZZO, CRISTIAN; BETTIOL, MARCO; BENNATI, PAOLO; PREZIOSI, ENRICO; PELLEGRINI, ROSANNA; PANI, ROBERTO
  • 11573/935757 - 2016 - Performance study of a PET scanner based on monolithic scintillators for different DoI-dependent methods (01a Articolo in rivista)
    PREZIOSI, ENRICO; PANI, ROBERTO; BORRAZZO, CRISTIAN; BETTIOL, MARCO
  • 11573/856706 - 2015 - Preliminary evaluation of a monolithic detector module for integrated PET/MRI scanner with high spatial resolution (01a Articolo in rivista)
    PANI, ROBERTO; BETTIOL, MARCO; FABBRI, ANDREA; CINTI, MARIA NERINA; PREZIOSI, ENRICO; BORRAZZO, CRISTIAN; PELLEGRINI, ROSANNA
  • 11573/874841 - 2016 - Depth-of-interaction discrimination to correct parallax error in high resolution PET (01a Articolo in rivista)
    BETTIOL, MARCO; PREZIOSI, ENRICO; BORRAZZO, CRISTIAN; CINTI, MARIA NERINA; PANI, ROBERTO
  • 11573/856702 - 2016 - Position algorithm for monolithic scintillation crystals based on charge projection readout (01a Articolo in rivista)
    PANI, ROBERTO; BETTIOL, MARCO; PREZIOSI, ENRICO; CINTI, MARIA NERINA; BORRAZZO, CRISTIAN; PELLEGRINI, ROSANNA; FABBRI, ANDREA
  • 11573/1041617 - 2017 - LaBr3:Ce and NaI:Tl performance comparison for single photon emission detector (01a Articolo in rivista)
    BETTIOL, MARCO; PREZIOSI, ENRICO; BORRAZZO, CRISTIAN; POLITO, CLAUDIA; PELLEGRINI, ROSANNA; PANI, ROBERTO
  • 11573/922221 - 2016 - A crystal identification method for mo- nolithic phoswich detectors based on scintillation light distribution (01a Articolo in rivista)
    PREZIOSI, ENRICO; POLITO, CLAUDIA; BETTIOL, MARCO; BORRAZZO, CRISTIAN; PELLEGRINI, ROSANNA; PANI, ROBERTO
  • 11573/856707 - 2015 - A novel method for γ photons depth of interaction discrimination on monolithic LYSO crystals for brain PET/MRI (04c Atto di convegno in rivista)
    PANI, ROBERTO; BETTIOL, MARCO; PREZIOSI, ENRICO; PELLEGRINI, ROSANNA; CINTI, MARIA NERINA; FABBRI, ANDREA; DI CASTRO, ELISABETTA
  • 11573/923227 - 2016 - A Depth-of-Interaction encoding method for SPECT monolithic scintillation detectors (04c Atto di convegno in rivista)
    BETTIOL, MARCO; PREZIOSI, ENRICO; BORRAZZO, CRISTIAN; PELLEGRINI, ROSANNA; PANI, ROBERTO
  • 11573/1389744 - 2019 - Novel Gamma Tracker for Rapid Radiation Direction Detection for UAV Drone Use (01a Articolo in rivista)
    PANI, ROBERTO; POLITO, CLAUDIA; FALCONI, RITA; FRANCIOSINI, GAIA; LONGO, MARIACONCETTA; BETTIOL, MARCO; FRANTELLIZZI, VIVIANA; DE VINCENTIS, GIUSEPPE
  • 11573/1392115 - 2020 - Characterization of monolithic GAGG:Ce coupled to both PMT and SiPM array for gamma imaging in nuclear medicine (04c Atto di convegno in rivista)
    PANI, ROBERTO; BETTIOL, MARCO; LONGO, MARIACONCETTA; POLITO, CLAUDIA; FALCONI, RITA; DE SIO, LUCIANO; PONTICO, MARIANO; DE VINCENTIS, GIUSEPPE; PELLEGRINI, ROSANNA; FRANTELLIZZI, VIVIANA
  • 11573/1416860 - 2020 - Imaging performance dependence on crystal absorption properties: the CRY018 and CRY019 comparison (04c Atto di convegno in rivista)
    PELLEGRINI, ROSANNA; POLITO, CLAUDIA; FALCONI, RITA; BETTIOL, MARCO; LONGO, MARIACONCETTA; DE VINCENTIS, GIUSEPPE; PANI, ROBERTO; FRANTELLIZZI, VIVIANA
  • 11573/460855 - 2012 - New position arithmetic for scintillation camera based on floating weight system (04b Atto di convegno in volume)
    PANI, ROBERTO; CINTI, MARIA NERINA; PELLEGRINI, ROSANNA; BETTIOL, MARCO; FABBRI, ANDREA
  • 11573/460776 - 2012 - Continuous DoI determination by gaussian modelling of linear and non-linear scintillation light distributions (04b Atto di convegno in volume)
    PANI, ROBERTO; NOURBAKHSH, SHERVIN; BENNATI, PAOLO; CINTI, MARIA NERINA; PELLEGRINI, ROSANNA; BETTIOL, MARCO

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