Physica Medica: European Journal of Medical Physics - Volume 32 - Supplement 1 - February 2016

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therefore, their potential in rehabilitation treatments should be further
investigated.
E.436
ARTERIAL SPIN LABELING (ASL) TECHNIQUE COULD BE USED AS
STANDARD CLINICAL TOOL?
M. Maieron F. Iaiza S. D’Agostini D. Bagatt F. Calzolar a SOC Fisica
Sanitaria, AOUD S. Maria della Misericordia di Udine, Udine, Italy; b SOC
Neuroradiologia, AOUD S. Maria della Misericordia di Udine, Udine, Italy
Introduction: The two most common methods for measuring perfusion using
MRI are the Dynamic Susceptibility Contrast (DSC) approach, which iden-
tifies the passage of an intravascular contrast agent, and the Arterial Spin
Labeling (ASL), which uses magnetically labeled arterial blood water as a dif-
fusible flow tracer. DSC perfusion is still the more widely applied clinical
technique but recent technical advances have improved the sensitivity of ASL
perfusion. It has been argued that ASL perfusion images are not clinically
reliable due to the low SNR. The objective of the current study was to eval-
uate the regional correlation between ASL perfusion measurement of CBF
in healthy subjects and patients with brain tumors in different brain areas.
Materials and Methods: 35 subjects were enrolled: 27 healthy subjects
(19 m/17 f, 44.6 y) and 8 patients (4 m/3 f, 57 y) with different brain lesions.
The study was performed using a 1.5 T MR scanner. Each subject received
an ASL scan and all the routine clinical MRI scans; a DSC scan was also ac-
quired only for patients. For all subjects, a series of ROIs in correspondence
to the white matter (WM) and gray matter (GM) have been drawn on the
ASL-CBF map; the same ROIs were also positioned on DSC-CBF map for all
patients. The perfusion ASL values from different regions were analyzed
using non parametric t-test. For patients, the ASL and DSC data have also
been compared.
Results and Conclusions: From the comparison between the ASL values it
was found that the values of the CBF were statistically higher in the GM
(33.5 ± 5.8 ml/100g/min) with respect to the WM (17.1 ± 5.7 mL/100g/min)
as expected. Frompatient data analysis, it was evident that ASL and DSC values
are in agreement with the type of lesions, WM, GM. Our study confirmed
that the ASL technique represents a valid alternative to conventional DSC.
In our experience the ASL was able to highlight the topographical distribu-
tion of CBF and to locate in patients ischemic and glial lesions.
E.437
TRANS-CRANIAL MRI-GUIDED FOCUSED ULTRASOUND SURGERY
(TCMRGFUS): ITALIAN AND WORLD-FIRST EXPERIENCE AT 1.5 TESLA
C. Gagliardo M. Marrale A. Napol L. Geraci G. Collura A. Franzin
G. Iacopino M. Brai C. Catalano M. Midiri a Sezione di Scienze
Radiologiche, Dipartimento di Biopatologia e Biotecnologie Mediche e Forensi
– Università di Palermo, Palermo, Italy; b Dipartimento di Fisica e Chimica –
Università di Palermo, Palermo, Italy; c Dipartimento Scienze Radiologiche,
Oncologiche e Anatomo-Patologiche – Università di Roma Sapienza, Roma, Italy;
d Neurochirurgia – Istituto Carlo Besta, Milano, Italy; e U.O. di Neurochirurgia,
Dipartimento di Emergenze, Urgenze e Neuroscienze Cliniche – Università di
Palermo, Palermo, Italy
Introduction: Transcranial magnetic resonance-guided focused ultra-
sound surgery (tcMRgFUS) is a promising new technology for the non-
invasive treatment of various brain disorders. Here, we present our
preliminary results achieved with the first Italian installation of a trans-
cranial MRI-guided focused ultrasound surgery (tcMRgFUS) certified system
for functional neurosurgery. Technical issues faced to achieve a safe and
effective treatment will be discussed focusing on MR high-resolution live
imaging and thermometry sequences optimization.
Materials and Methods: Patient enrollment was based on indication for
functional neurosurgery and evidence of medication-refractory disease; a
detailed medical history has been collected together with a complete clin-
ical examination and a neurophysiological assessment. Eligible patients have
been screened by MDCT and MRI.
Results: Although this is a preliminary experience, the clinical success of
our first treatments proves that this promising new technology for
non-invasive treatment of various brain disorders can be safely and effec-
tively performed also with the most popular MRI units operating at 1.5 T.
Conclusion: TcMRgFUS treatments are currently performed in a very few
centers in the world and only using 3 T MRI units. This is the world-first
experience of functional neurosurgery successfully performed with a
tcMRgFUS installed on the most popular and affordable 1.5 T MR units.
Thanks to the use of a radiation-free technique like the MRI as a guide and
to the possibility of verifying the clinical effectiveness of such an innova-
tive treatment before a permanent lesion is made in the targeted area of
the brain, this technique allows for a huge step forward for both
interventional neuroradiology and functional neurosurgery.
E.438
COMPARATIVE EVALUATION OF DATA PREPROCESSING SOFTWARE TOOLS
TO INCREASE EFFICIENCY AND ACCURACY IN DIFFUSION KURTOSIS
IMAGING
M. Marrale * G. Collura S. Gallo A. Longo S. Panzeca
C. Gagliard M. Midiri M. Brai a Dipartimento di Fisica e Chimica,
Università di Palermo, Palermo, Italy; b Istituto Nazionale di Fisica Nucleare
(INFN) Gruppo V Sez. Catania, Catania, Italy; c Scuola di Specializzazione in
Fisica Medica, Università di Palermo, Palermo, Italy; d Dipartimento di
Biopatologia e Biotecnologie Mediche Forensi, Università di Palermo, Palermo,
Italy
Introduction: Diffusion tensor imaging (DTI) is the most commonly used
technique to extract microstructural features from a set of diffusion weighted
images. In addition to the metrics obtained with DTI, diffusion kurtosis
imaging (DKI) can provide non-Gaussian diffusion measures by means of
the kurtosis tensor.
DKI has shown to be more sensitive to tissue microstructural changes in
both normal and pathological neural tissue.
In a clinical setting, however, these benefits are often nullified by numer-
ous acquisition artifacts. The aim of this study was compare two pre-
processing software for DTI apply to DKI. Also, the major preprocessing,
processing and post-processing procedures applied to DKI data are discussed.
Materials and Methods: The reproducibility typical to DKI parameters ob-
tained from the same dataset using two DTI analysis software tools was
evaluated by the image quality measurements in regions of interest on 10
DKI datasets. The data were corrected for motion and eddy current arti-
facts using two different softwares: ExploreDTI
and TORTOISE DIFF_PREP
.
The data analysis was performed using in-house developed software imple-
mented in Python.
Results: The performances of these approaches were compared with Monte
Carlo simulations. A quantitative analysis of differences of typical DKI maps
obtained from data preprocessed with these two packages was per-
formed and the advantages and disadvantages of each tool are highlighted.
Conclusion: This work is aimed at providing useful indications for appli-
cation of DKI in clinical settings where artifacts in diffusion weighted images
are common and may affect DKI measurements and the lack of standard
procedures for post-processing might become a significant issue for the
use of DKI in clinical routine.
E.439
RESTING STATE FMRI: A TOOL TO INVESTIGATE FUNCTIONAL
CONNECTIVITY MODULATION INDUCED BY TRANSCRANIAL DIRECT
CURRENT STIMULATION OF THE MOTOR NETWORK
M. Marrale S. Nic G. Collur S. Gall A. Longo S. Panzec
T. Piccoli C. Gagliard M. Midiri M. Brai a Dipartimento di Fisica e
Chimica, Università di Palermo, Palermo, Italy; b Istituto Nazionale di Fisica
Nucleare (INFN) Gruppo V Sez. Catania, Catania, Italy; c Scuola di
Specializzazione in Fisica Medica, Università di Palermo, Palermo, Italy;
d Dipartimento di Biomedicina Sperimentale e Neuroscienze Cliniche, Università
di Palermo, Palermo, Italy; e Dipartimento di Biopatologia e Biotecnologie
Mediche Forensi, Università di Palermo, Palermo, Italy
e129 Abstracts/Physica Medica 32 (2016) e124–e134