Hi All,
I have collected T1 3D FLASH on a subject and here are some details of the sequence,
Manufacturer = SIEMENS StudyDescription = Neuro_3T^brain_3t SeriesDescription = Axial Global FLASH FA27 ManufacturersModelName = Verio ReferencedImageSequence = 1.2.840.10008.5.1.4.1.1.4\1.3.12.2.1107.5.2.36.40156.30000013112219461598300005978\1.2.840.10008.5.1.4.1.1.4\1.3.12.2.1107.5.2.36.40156.30000013112219461598300005980\1.2.840.10008.5.1.4.1.1.4\1.3.12.2.1107.5.2.36.40156.30000013112219461598300005979 ScanningSequence = GR SequenceVariant = SP ScanOptions = SAT1 MRAcquisitionType = 3D SequenceName = *fl3d1 SliceThickness = 1 RepetitionTime = 20 EchoTime = 5 InversionTime = - NumberofAverages = 1 ImagingFrequency = 123.200338 ImagedNucleus = 1H EchoNumbers = 1 MagneticFieldStrength = 3 NumberofPhaseEncodingSteps = 192 EchoTrainLength = 1 PercentSampling = 100 PercentPhaseFieldofView = 75 PixelBandwidth = 179 DeviceSerialNumber = 40156 SoftwareVersions = syngo MR B17 ProtocolName = Axial Global FLASH FA27 TransmitCoilName = Body AcquisitionMatrix = 0\256\192\0 In-planePhaseEncodingDirection = ROW FlipAngle = 27 VariableFlipAngleFlag = N SAR = 0.19411263
My questions are the following -
1) Can I get reliable cortical thickness estimates using a T1 3D FLASH sequence at 3T Siemens TRIO ?
2) Which version of freesurfer is recommended ?
3) One reason, I collected T1 FLASH is I want to get whole brain volume and brain parenchymal fraction in Multiple sclerosis patients. But if freesurfer prefers MPRAGES over FLASH for cortical thickness, I am wondering how reliable are the standard MPRAGE sequences for calculation of whole brain volume and brain parenchymal fractions ?
4) I ran the recon on the FLASH using freesurfer 5.3 and it looks very decent but has anyone tested and optimized the parameters for the T1 FLASH sequence for cortical thickness estimations ?
5) If you can share your opinion and experiences in this topic and maybe point me to some references using flash and freesurfer for cortical thickness, that will be very helpful.
Best
Ri