Methods (Supplementary)

METHODS (SUPPLEMENTARY)

The patient underwent brainSPECT with99mTc-HMPAO, alipophilicradiopharmaceuticalusedfor the assessment ofcerebral perfusion. This product waspreparedusing a commercial kit(Ceretec ®, GE Healthcare Italy, Milan) to which were added740MBq of99mTc-sodium pertechnetatein 2 ml ofsaline.The final productunderwentascending chromatographyon paper, according to the instructionsprovided by the manufacturer, in order to calculatethe yieldoflabelingand the presence ofany impurities. Theradiopharmaceuticalwas administeredto the patientintravenously ina time intervalof 15 minutes fromits preparation. Afterplacement of acannula ina vein of thearm, the patient was placedon a bedofgamma-cameraandkept away fromlight and soundstimulationfor 15 minutes.The patient head was fixed in the orbito-meatal line position by a hemi-cylindrical plastic head-holder.The above mentioned dose of99mTc-HMPAO was subsequentlyadministered intravenously. Forty minutesafter the injection,patientswere submitted tobrainSPECTby a dual-head, large-field-of-view gamma camera(Infinia®,GE Healthcare Italy, Milan) equipped with ahigh-resolution collimatorwithparallel holesforlow energies. This device has a spatial resolution equal to 8 mm, which, as demonstrated from the large use of SPECT in clinical practice, is sufficient for an adequate spatial representation of cerebral perfusion. The acquisitionwas performed ona circular orbit of360degrees,with the smallestpossibleradius, withsamplingangleof about3 degreesand a time of25 seconds perprojection, withacquisition matrix128X128. Theenergy windowwas positionedon the peak of99mTc(140 keV ± 10%). Image reconstructionwas performed usingfiltered back projectionwith aButterworth filterandarampfilter. Transaxial, coronal andsagitalsections,oriented alongtheorbito-meatal line, were than generated. Image analysiswas performed using a specific software (Neurogam®, GE Healthcare Italy, Milan) capable of providing for each cerebral area the mean and thestandard deviation of thecountsrecordedexpressed asa percentage of themaximum count–rate registeredon the encephalon. Tenregions of interest were selected, corresponding to the entirecortexand the parietal, temporal, frontaland occipitalregions.The dataof the first, second and third testwere compared with each other.

TABLE S1

ROI Label
CNl / CNr / FLl / FLr / OLl / OLr / PLl / PLr / TLl / TLr
I SPECT / Mean / 0,31 / 29,40 / 21,40 / 60,5 / 54,9 / 67,1 / 55,5 / 61,9 / 61,9 / 63,8
SD / 8,30 / 8,40 / 14,40 / 14 / 13,6 / 13 / 14 / 14 / 13,8 / 13,4
II SPECT / Mean / 42,10 / 45,60 / 55,60 / 56,60 / 62,70 / 66,50 / 61,20 / 62,40 / 66,70 / 68,90
SD / 12,00 / 12,10 / 17,80 / 15,90 / 13,30 / 12,50 / 14,60 / 14,00 / 12,20 / 10,60
III SPECT / Mean / 56,30 / 50,80 / 59,80 / 62,80 / 66,50 / 64,70 / 60,90 / 62,80 / 65,70 / 67,00
SD / 8,60 / 9,80 / 15,60 / 12,90 / 11,20 / 11,40 / 15,30 / 14,50 / 11,90 / 10,10