NIMH Data Archive - Data Dictionary: Data Structure

Magnetic Resonance Image Quality Metrics

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Description N/A

Data type Neurosignal Recordings

Categories

Evaluated Data

Date created 04/12/2019

Short name mriqm01

Most Recent Update 04/12/2019
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Definition

Submission Template

Element Name	Data Type	Size	Required	Description	Value Range	Notes	Aliases
subjectkey	GUID		Required	The NDAR Global Unique Identifier (GUID) for research subject	NDAR*
src_subject_id	String	20	Required	Subject ID how it's defined in lab/project			subject_id
interview_date	Date		Required	Date on which the interview/genetic test/sampling/imaging/biospecimen was completed. MM/DD/YYYY
interview_age	Integer		Required	Age in months at the time of the interview/test/sampling/imaging.	0::1440	Age is rounded to chronological month. If the research participant is 15-days-old at time of interview, the appropriate value would be 0 months. If the participant is 16-days-old, the value would be 1 month.
sex	String	20	Required	Sex of subject at birth	M;F; O; NR	M = Male; F = Female; O=Other; NR = Not reported	gender
scan_type	String	50	Required	Type of Scan	MR diffusion; fMRI; MR structural (MPRAGE); MR structural (T1); MR structural (PD); MR structural (FSPGR); MR structural (FISP); MR structural (T2); PET; ASL; microscopy; MR structural (PD, T2); MR structural (B0 map); MR structural (B1 map); single-shell DTI; multi-shell DTI; Field Map; X-Ray; static magnetic field B0; pCASL: ASL; MR: T2star; MR: FLAIR; Localizer scan; MR structural (FLASH); MR structural (MP2RAGE); MR structural (TSE); MR structural (T1, T2); 2D gradient echo; MR structural (MPnRAGE); Magnetic Resonance Spectroscopy(MRS); Neuromelanin MRI (NM-MRI); Functional Near Infrared Spectroscopy(fNIRS); MT; Magnetic Resonance Elastography (MRE); T1rho Spin-lock image
t1_cjv	Float		Conditional	coefficient of joint variation (CJV): The cjv of GM and WM was proposed as objective function by [Ganzetti2016] for the optimization of INU correction algorithms. Higher values are related to the presence of heavy head motion and large INU artifacts. Lower values are better.
t1_cnr	Float		Conditional	contrast-to-noise ratio (CNR): The cnr [Magnota2006], is an extension of the SNR calculation to evaluate how separated the tissue distributions of GM and WM are. Higher values indicate better quality.
t1_efc	Float		Conditional	The EFC [Atkinson1997] uses the Shannon entropy of voxel intensities as an indication of ghosting and blurring induced by head motion. Lower values are better. The original equation is normalized by the maximum entropy, so that the EFC can be compared across images with different dimensions.
t1_fber	Float		Conditional	The FBER [Shehzad2015], defined as the mean energy of image values within the head relative to outside the head [QAP-measures]. Higher values are better.
t1_fwhm_avg	Float		Conditional	The FWHM of the spatial distribution of the image intensity values in units of voxels [Forman1995]. Lower values are better. Uses the gaussian width estimator filter implemented in AFNI's 3dFWHMx
t1_fwhm_x	Float		Conditional	The FWHM of the spatial distribution of the image intensity values in units of voxels [Forman1995]. Lower values are better. Uses the gaussian width estimator filter implemented in AFNI's 3dFWHMx
t1_fwhm_y	Float		Conditional	The FWHM of the spatial distribution of the image intensity values in units of voxels [Forman1995]. Lower values are better. Uses the gaussian width estimator filter implemented in AFNI's 3dFWHMx
t1_fwhm_z	Float		Conditional	The FWHM of the spatial distribution of the image intensity values in units of voxels [Forman1995]. Lower values are better. Uses the gaussian width estimator filter implemented in AFNI's 3dFWHMx
t1_icvs_csf	Float		Conditional	The ICV fractions of CSF, GM and WM. They should move within a normative range.
t1_icvs_gm	Float		Conditional	The ICV fractions of CSF, GM and WM. They should move within a normative range.
t1_icvs_wm	Float		Conditional	The ICV fractions of CSF, GM and WM. They should move within a normative range.
t1_inu_med	Float		Conditional	summary statistics (max, min and median) of the INU field as extracted by the N4ITK algorithm [Tustison2010]. Values closer to 1.0 are better.
t1_inu_range	Float		Conditional	summary statistics (max, min and median) of the INU field as extracted by the N4ITK algorithm [Tustison2010]. Values closer to 1.0 are better.
t1_qi_1	Float		Conditional	Detect artifacts in the image using the method described in [Mortamet2009]. The QI1 is the proportion of voxels with intensity corrupted by artifacts normalized by the number of voxels in the background. Lower values are better.
t1_qi_2	Float		Conditional	Mortamet's quality index 2 (QI2) is a calculation of the goodness-of-fit of a chi-2 distribution on the air mask, once the artifactual intensities detected for computing the QI1 index have been removed [Mortamet2009].
t1_rpve_csf	Float		Conditional	the rPVe of CSF, GM and WM. Lower values are better.
t1_rpve_gm	Float		Conditional	the rPVe of CSF, GM and WM. Lower values are better.
t1_rpve_wm	Float		Conditional	the rPVe of CSF, GM and WM. Lower values are better.
t1_size_x	Integer		Conditional	extent in number of voxels
t1_size_y	Integer		Conditional	extent in number of voxels
t1_size_z	Integer		Conditional	extent in number of voxels
t1_snr_csf	Float		Conditional	signal-to-noise ratio (SNR): calculated within the tissue mask.
t1_snr_gm	Float		Conditional	signal-to-noise ratio (SNR): calculated within the tissue mask.
t1_snr_total	Float		Conditional	signal-to-noise ratio (SNR): calculated within the tissue mask.
t1_snr_wm	Float		Conditional	signal-to-noise ratio (SNR): calculated within the tissue mask.
t1_snrd_csf	Float		Conditional	Dietrich's SNR (SNRd) as proposed by [Dietrich2007], using the air background as reference.
t1_snrd_gm	Float		Conditional	Dietrich's SNR (SNRd) as proposed by [Dietrich2007], using the air background as reference.
t1_snrd_total	Float		Conditional	Dietrich's SNR (SNRd) as proposed by [Dietrich2007], using the air background as reference.
t1_snrd_wm	Float		Conditional	Dietrich's SNR (SNRd) as proposed by [Dietrich2007], using the air background as reference.
t1_spacing_x	Float		Conditional	Distance in mm betwen centers of adjacent voxels in x direction
t1_spacing_y	Float		Conditional	Distance in mm betwen centers of adjacent voxels in y direction
t1_spacing_z	Float		Conditional	Distance in mm betwen centers of adjacent voxels in z direction
t1_summary_bg_k	Float		Conditional	background kurtosis
t1_summary_bg_mad	Float		Conditional	background median absolute deviation
t1_summary_bg_mean	Float		Conditional	background mean
t1_summary_bg_median	Float		Conditional	background median absolute deviation
t1_summary_bg_n	Float		Conditional	background count of voxels
t1_summary_bg_p05	Float		Conditional	background 5th percentile
t1_summary_bg_p95	Float		Conditional	background 95th percentile
t1_summary_bg_stdv	Float		Conditional	background standard deviation
t1_summary_csf_k	Float		Conditional	cerebrospinal fluid kurtosis
t1_summary_csf_mad	Float		Conditional	cerebrospinal fluid median absolute deviation
t1_summary_csf_mean	Float		Conditional	cerebrospinal fluid mean
t1_summary_csf_median	Float		Conditional	cerebrospinal fluid median absolute deviation
t1_summary_csf_n	Float		Conditional	cerebrospinal fluid count of voxels
t1_summary_csf_p05	Float		Conditional	cerebrospinal fluid 5th percentile
t1_summary_csf_p95	Float		Conditional	cerebrospinal fluid 95th percentile
t1_summary_csf_stdv	Float		Conditional	cerebrospinal fluid standard deviation
t1_summary_gm_k	Float		Conditional	grey matter kurtosis
t1_summary_gm_mad	Float		Conditional	grey matter median absolute deviation
t1_summary_gm_mean	Float		Conditional	grey matter mean
t1_summary_gm_median	Float		Conditional	grey matter median absolute deviation
t1_summary_gm_n	Float		Conditional	grey matter count of voxels
t1_summary_gm_p05	Float		Conditional	grey matter 5th percentile
t1_summary_gm_p95	Float		Conditional	grey matter 95th percentile
t1_summary_gm_stdv	Float		Conditional	grey matter standard deviation
t1_summary_wm_k	Float		Conditional	white matter kurtosis
t1_summary_wm_mad	Float		Conditional	white matter median absolute deviation
t1_summary_wm_mean	Float		Conditional	white matter mean
t1_summary_wm_median	Float		Conditional	white matter median absolute deviation
t1_summary_wm_n	Float		Conditional	white matter count of voxels
t1_summary_wm_p05	Float		Conditional	white matter 5th percentile
t1_summary_wm_p95	Float		Conditional	white matter 95th percentile
t1_summary_wm_stdv	Float		Conditional	white matter standard deviation
t1_tpm_overlap_csf	Float		Conditional	The overlap of the TPMs estimated from the image and the corresponding maps from the ICBM nonlinear-asymmetric 2009c template.
t1_tpm_overlap_gm	Float		Conditional	The overlap of the TPMs estimated from the image and the corresponding maps from the ICBM nonlinear-asymmetric 2009c template.
t1_tpm_overlap_wm	Float		Conditional	The overlap of the TPMs estimated from the image and the corresponding maps from the ICBM nonlinear-asymmetric 2009c template.
t1_wm2max	Float		Conditional	The overlap of the TPMs estimated from the image and the corresponding maps from the ICBM nonlinear-asymmetric 2009c template.
t2_cjv	Float		Conditional	coefficient of joint variation (CJV): The cjv of GM and WM was proposed as objective function by [Ganzetti2016] for the optimization of INU correction algorithms. Higher values are related to the presence of heavy head motion and large INU artifacts. Lower values are better.
t2_cnr	Float		Conditional	contrast-to-noise ratio (CNR): The cnr [Magnota2006], is an extension of the SNR calculation to evaluate how separated the tissue distributions of GM and WM are. Higher values indicate better quality.
t2_efc	Float		Conditional	The EFC [Atkinson1997] uses the Shannon entropy of voxel intensities as an indication of ghosting and blurring induced by head motion. Lower values are better. The original equation is normalized by the maximum entropy, so that the EFC can be compared across images with different dimensions.
t2_fber	Float		Conditional	The FBER [Shehzad2015], defined as the mean energy of image values within the head relative to outside the head [QAP-measures]. Higher values are better.
t2_fwhm_avg	Float		Conditional	The FWHM of the spatial distribution of the image intensity values in units of voxels [Forman1995]. Lower values are better. Uses the gaussian width estimator filter implemented in AFNI's 3dFWHMx
t2_fwhm_x	Float		Conditional	The FWHM of the spatial distribution of the image intensity values in units of voxels [Forman1995]. Lower values are better. Uses the gaussian width estimator filter implemented in AFNI's 3dFWHMx
t2_fwhm_y	Float		Conditional	The FWHM of the spatial distribution of the image intensity values in units of voxels [Forman1995]. Lower values are better. Uses the gaussian width estimator filter implemented in AFNI's 3dFWHMx
t2_fwhm_z	Float		Conditional	The FWHM of the spatial distribution of the image intensity values in units of voxels [Forman1995]. Lower values are better. Uses the gaussian width estimator filter implemented in AFNI's 3dFWHMx
t2_icvs_csf	Float		Conditional	The ICV fractions of CSF, GM and WM. They should move within a normative range.
t2_icvs_gm	Float		Conditional	The ICV fractions of CSF, GM and WM. They should move within a normative range.
t2_icvs_wm	Float		Conditional	The ICV fractions of CSF, GM and WM. They should move within a normative range.
t2_inu_med	Float		Conditional	summary statistics (max, min and median) of the INU field as extracted by the N4ITK algorithm [Tustison2010]. Values closer to 1.0 are better.
t2_inu_range	Float		Conditional	summary statistics (max, min and median) of the INU field as extracted by the N4ITK algorithm [Tustison2010]. Values closer to 1.0 are better.
t2_qi_1	Float		Conditional	Detect artifacts in the image using the method described in [Mortamet2009]. The QI1 is the proportion of voxels with intensity corrupted by artifacts normalized by the number of voxels in the background. Lower values are better.
t2_qi_2	Float		Conditional	Mortamet's quality index 2 (QI2) is a calculation of the goodness-of-fit of a chi-2 distribution on the air mask, once the artifactual intensities detected for computing the QI1 index have been removed [Mortamet2009].
t2_rpve_csf	Float		Conditional	the rPVe of CSF, GM and WM. Lower values are better.
t2_rpve_gm	Float		Conditional	the rPVe of CSF, GM and WM. Lower values are better.
t2_rpve_wm	Float		Conditional	the rPVe of CSF, GM and WM. Lower values are better.
t2_size_x	Integer		Conditional	extent in number of voxels
t2_size_y	Integer		Conditional	extent in number of voxels
t2_size_z	Integer		Conditional	extent in number of voxels
t2_snr_csf	Float		Conditional	signal-to-noise ratio (SNR): calculated within the tissue mask.
t2_snr_gm	Float		Conditional	signal-to-noise ratio (SNR): calculated within the tissue mask.
t2_snr_total	Float		Conditional	signal-to-noise ratio (SNR): calculated within the tissue mask.
t2_snr_wm	Float		Conditional	signal-to-noise ratio (SNR): calculated within the tissue mask.
t2_snrd_csf	Float		Conditional	Dietrich's SNR (SNRd) as proposed by [Dietrich2007], using the air background as reference.
t2_snrd_gm	Float		Conditional	Dietrich's SNR (SNRd) as proposed by [Dietrich2007], using the air background as reference.
t2_snrd_total	Float		Conditional	Dietrich's SNR (SNRd) as proposed by [Dietrich2007], using the air background as reference.
t2_snrd_wm	Float		Conditional	Dietrich's SNR (SNRd) as proposed by [Dietrich2007], using the air background as reference.
t2_spacing_x	Float		Conditional	Distance in mm betwen centers of adjacent voxels in x direction
t2_spacing_y	Float		Conditional	Distance in mm betwen centers of adjacent voxels in y direction
t2_spacing_z	Float		Conditional	Distance in mm betwen centers of adjacent voxels in z direction
t2_summary_bg_k	Float		Conditional	background kurtosis
t2_summary_bg_mad	Float		Conditional	background median absolute deviation
t2_summary_bg_mean	Float		Conditional	background mean
t2_summary_bg_median	Float		Conditional	background median absolute deviation
t2_summary_bg_n	Float		Conditional	background count of voxels
t2_summary_bg_p05	Float		Conditional	background 5th percentile
t2_summary_bg_p95	Float		Conditional	background 95th percentile
t2_summary_bg_stdv	Float		Conditional	background standard deviation
t2_summary_csf_k	Float		Conditional	cerebrospinal fluid kurtosis
t2_summary_csf_mad	Float		Conditional	cerebrospinal fluid median absolute deviation
t2_summary_csf_mean	Float		Conditional	cerebrospinal fluid mean
t2_summary_csf_median	Float		Conditional	cerebrospinal fluid median absolute deviation
t2_summary_csf_n	Float		Conditional	cerebrospinal fluid count of voxels
t2_summary_csf_p05	Float		Conditional	cerebrospinal fluid 5th percentile
t2_summary_csf_p95	Float		Conditional	cerebrospinal fluid 95th percentile
t2_summary_csf_stdv	Float		Conditional	cerebrospinal fluid standard deviation
t2_summary_gm_k	Float		Conditional	grey matter kurtosis
t2_summary_gm_mad	Float		Conditional	grey matter median absolute deviation
t2_summary_gm_mean	Float		Conditional	grey matter mean
t2_summary_gm_median	Float		Conditional	grey matter median absolute deviation
t2_summary_gm_n	Float		Conditional	grey matter count of voxels
t2_summary_gm_p05	Float		Conditional	grey matter 5th percentile
t2_summary_gm_p95	Float		Conditional	grey matter 95th percentile
t2_summary_gm_stdv	Float		Conditional	grey matter standard deviation
t2_summary_wm_k	Float		Conditional	white matter kurtosis
t2_summary_wm_mad	Float		Conditional	white matter median absolute deviation
t2_summary_wm_mean	Float		Conditional	white matter mean
t2_summary_wm_median	Float		Conditional	white matter median absolute deviation
t2_summary_wm_n	Float		Conditional	white matter count of voxels
t2_summary_wm_p05	Float		Conditional	white matter 5th percentile
t2_summary_wm_p95	Float		Conditional	white matter 95th percentile
t2_summary_wm_stdv	Float		Conditional	white matter standard deviation
t2_tpm_overlap_csf	Float		Conditional	The overlap of the TPMs estimated from the image and the corresponding maps from the ICBM nonlinear-asymmetric 2009c template.
t2_tpm_overlap_gm	Float		Conditional	The overlap of the TPMs estimated from the image and the corresponding maps from the ICBM nonlinear-asymmetric 2009c template.
t2_tpm_overlap_wm	Float		Conditional	The overlap of the TPMs estimated from the image and the corresponding maps from the ICBM nonlinear-asymmetric 2009c template.
t2_wm2max	Float		Conditional	The white-matter to maximum intensity ratio is the median intensity within the WM mask over the 95% percentile of the full intensity distribution, that captures the existence of long tails due to hyper-intensity of the carotid vessels and fat. Values should be around the interval [0.6, 0.8].
bold_dummy_trs	Integer		Conditional	Number of volumes (“dummy scans”) discarded by the scanner (as opposed to those discarded by the user post hoc) before saving the imaging file. For example, a sequence that automatically discards the first 4 volumes before saving would have this field as 4. A sequence that doesn’t discard dummy scans would have this set to 0.
bold_dvars_nstd	Float		Conditional	D referring to temporal derivative of timecourses, VARS referring to RMS variance over voxels ([Power2012] dvars_nstd) indexes the rate of change of BOLD signal across the entire brain at each frame of data. DVARS is calculated with nipype after motion correction
bold_dvars_std	Float		Conditional	D referring to temporal derivative of timecourses, VARS referring to RMS variance over voxels ([Power2012] dvars_nstd) indexes the rate of change of BOLD signal across the entire brain at each frame of data. DVARS is calculated with nipype after motion correction
bold_dvars_vstd	Float		Conditional	D referring to temporal derivative of timecourses, VARS referring to RMS variance over voxels ([Power2012] dvars_nstd) indexes the rate of change of BOLD signal across the entire brain at each frame of data. DVARS is calculated with nipype after motion correction
bold_efc	Float		Conditional	The EFC [Atkinson1997] uses the Shannon entropy of voxel intensities as an indication of ghosting and blurring induced by head motion. Lower values are better. The original equation is normalized by the maximum entropy, so that the EFC can be compared across images with different dimensions.
bold_fber	Float		Conditional	The FBER [Shehzad2015], defined as the mean energy of image values within the head relative to outside the head [QAP-measures]. Higher values are better.
bold_fd_mean	Float		Conditional	expresses instantaneous head-motion. MRIQC reports the average FD, labeled as fd_mean. Rotational displacements are calculated as the displacement on the surface of a sphere of radius 50 mm. Along with the base framewise displacement, MRIQC reports the number of timepoints above FD threshold (fd_num), and the percent of FDs above the FD threshold w.r.t. the full timeseries (fd_perc). In both cases, the threshold is set at 0.20mm. [Power2012]:
bold_fd_num	Float		Conditional	expresses instantaneous head-motion. MRIQC reports the average FD, labeled as fd_mean. Rotational displacements are calculated as the displacement on the surface of a sphere of radius 50 mm. Along with the base framewise displacement, MRIQC reports the number of timepoints above FD threshold (fd_num), and the percent of FDs above the FD threshold w.r.t. the full timeseries (fd_perc). In both cases, the threshold is set at 0.20mm. [Power2012]:
bold_fd_perc	Float		Conditional	expresses instantaneous head-motion. MRIQC reports the average FD, labeled as fd_mean. Rotational displacements are calculated as the displacement on the surface of a sphere of radius 50 mm. Along with the base framewise displacement, MRIQC reports the number of timepoints above FD threshold (fd_num), and the percent of FDs above the FD threshold w.r.t. the full timeseries (fd_perc). In both cases, the threshold is set at 0.20mm. [Power2012]:
bold_fwhm_avg	Float		Conditional	The FWHM of the spatial distribution of the image intensity values in units of voxels [Forman1995]. Lower values are better. Uses the gaussian width estimator filter implemented in AFNI's 3dFWHMx
bold_fwhm_x	Float		Conditional	The FWHM of the spatial distribution of the image intensity values in units of voxels [Forman1995]. Lower values are better. Uses the gaussian width estimator filter implemented in AFNI's 3dFWHMx
bold_fwhm_y	Float		Conditional	The FWHM of the spatial distribution of the image intensity values in units of voxels [Forman1995]. Lower values are better. Uses the gaussian width estimator filter implemented in AFNI's 3dFWHMx
bold_fwhm_z	Float		Conditional	The FWHM of the spatial distribution of the image intensity values in units of voxels [Forman1995]. Lower values are better. Uses the gaussian width estimator filter implemented in AFNI's 3dFWHMx
bold_gcor	Float		Conditional	Global Correlation (gcor) calculates an optimized summary of time-series correlation as in [Saad2013] using AFNI's @compute_gcor
bold_gsr_x	Float		Conditional	Ghost to Signal Ratio (gsr(), labeled in the reports as gsr_x and gsr_y): along the two possible phase-encoding axes x, y
bold_gsr_y	Float		Conditional	Ghost to Signal Ratio (gsr(), labeled in the reports as gsr_x and gsr_y): along the two possible phase-encoding axes x, y
bold_prov_set_fd_thresh	Float		Conditional	Provisional setting of framewise displacement threshold
bold_size_t	Float		Conditional	number of time points
bold_size_x	Float		Conditional	extent in number of voxels
bold_size_y	Float		Conditional	extent in number of voxels
bold_size_z	Float		Conditional	extent in number of voxels
bold_snr	Float		Conditional	signal-to-noise ratio (SNR): calculated within the tissue mask.
bold_spacing_tr	Float		Conditional	Length of time between the begining of adjacent trs in s
bold_spacing_x	Float		Conditional	Distance in mm betwen centers of adjacent voxels in x direction
bold_spacing_y	Float		Conditional	Distance in mm betwen centers of adjacent voxels in y direction
bold_spacing_z	Float		Conditional	Distance in mm betwen centers of adjacent voxels in z direction
bold_summary_bg_k	Float		Conditional	background kurtosis
bold_summary_bg_mad	Float		Conditional	background median absolute deviation
bold_summary_bg_mean	Float		Conditional	background mean
bold_summary_bg_median	Float		Conditional	background median absolute deviation
bold_summary_bg_n	Float		Conditional	background count of voxels
bold_summary_bg_p05	Float		Conditional	background 5th percentile
bold_summary_bg_p95	Float		Conditional	background 95th percentile
bold_summary_bg_stdv	Float		Conditional	background standard deviation
bold_summary_fg_k	Float		Conditional	foreground kurtosis
bold_summary_fg_mad	Float		Conditional	foreground median absolute deviation
bold_summary_fg_mean	Float		Conditional	foreground mean
bold_summary_fg_median	Float		Conditional	foreground median absolute deviation
bold_summary_fg_n	Float		Conditional	foreground count of voxels
bold_summary_fg_p05	Float		Conditional	foreground 5th percentile
bold_summary_fg_p95	Float		Conditional	foreground 95th percentile
bold_summary_fg_stdv	Float		Conditional	foreground standard deviation
bold_tsnr	Float		Conditional	Temporal SNR (tSNR, tsnr) is a simplified interpretation of the tSNR definition [Kruger2001]. We report the median value of the tSNR map calculated like: where _S_t is the average BOLD signal (across time), and _t is the corresponding temporal standard-deviation map.
accelnumreferencelines	Float		Recommended	Acceleration number of reference lines
accelerationfactorpe	Float		Recommended	Acceleration factor in the phase encode direction
acquisitionmatrix	String	50	Recommended	Dimensions of the acquired frequency /phase data before reconstruction. Multi-valued: frequency rowsfrequency columnsphase rowsphase columns. ID=DICOM:0018_1310
cogatlasid	String	50	Recommended	URL for task in the cognitive atlas (http://www.cognitiveatlas.org)
cogpoid	String	50	Recommended	URL for task in cogpowiki(http://wiki.cogpo.org)
coilcombinationmethod	Float		Recommended	Almost all fMRI studies using phased-array coils use root-sum-of-squares (rSOS) combination, but other methods exist. The image reconstruction is changed by the coil combination method (as for the matrix coil mode above), so anything non-standard should be reported
conversionsoftware	String	50	Recommended	Software used to convert dicom to nifti
conversionsoftwareversion	String	50	Recommended	Release version of the software used to convert dicom to nifti
cardiactriggerdelaytimes	Float		Recommended	Cardiac Trigger Delay Times
deviceserialnumber	String	200	Recommended	device serial number/ID
echotime	Float		Recommended	Time in ms between the middle of the excitation pulse and the peak of the echo produced (kx=0). In the case of segmented k-space, the TE(eff) is the time between the middle of the excitation pulse to the peak of the echo that is used to cover the center of k-space (i.e.,-kx=0, ky=0). ID=DICOM:0018_0081
echotrainlength	Float		Recommended	Number of lines in k-space acquired per excitation of the same volume regardless of the type of echo or the number of frames derived from them. ID:DICOM:0018_0091
effectiveechospacing	Float		Recommended	The "effective" sampling interval, specified in seconds, between lines in the phase-encoding direction, defined based on the size of the reconstructed image in the phase direction. It is frequently, but incorrectly, referred to as "dwell time" (see DwellTime parameter below for actual dwell time). It is required for unwarping distortions using field maps. Note that beyond just in-plane acceleration, a variety of other manipulations to the phase encoding need to be accounted for properly, including partial fourier, phase oversampling, phase resolution, phase field-of-view and interpolation.2 This parameter is REQUIRED if corresponding fieldmap data is present.
flipangle	Float		Recommended	Flip angle for the acquisition, specified in degrees. Corresponds to: DICOM Tag 0018, 1314 Flip Angle.
hardcopydevicesoftwareversion	String	50	Recommended	Manufacturers designation of the software of the device that created this Hardcopy Image (the printer). Corresponds to DICOM Tag 0018, 101A Hardcopy Device Software Version
imagetype	String	50	Recommended	Image Type
imagingfrequency	Float		Recommended	Imaging Frequency
inplanephaseencodingdirection	String	50	Recommended	The axes of the in-plane phase encoding with respect to the frame. ID:DICOM:0018_1312
institutionaddress	String	50	Recommended	Mailing Address of the institution where the equipment is located.ID:DICOM:0008_0081
institutionname	String	50	Recommended	The name of the institution in charge of the equipment that produced the composite instances. Corresponds to DICOM Tag 0008, 0080 InstitutionName.
inst	String	50	Recommended	Text of the instructions given to participants before the scan. This is especially important in context of resting state fMRI and distinguishing between eyes open and eyes closed paradigms.			instructions
inversiontime	Float		Recommended	The inversion time (TI) for the acquisition, specified in seconds. Inversion time is the time after the middle of inverting RF pulse to middle of excitation pulse to detect the amount of longitudinal magnetization. Corresponds to DICOM Tag 0018, 0082 Inversion Time (please note that the DICOM term is in milliseconds not seconds).
mracquisitiontype	String	50	Recommended	Identification of data encoding scheme. ID:DICOM:0018_0023
magneticfieldstrength	Float		Recommended	Nominal field strength of MR magnet in Tesla. ID:DICOM:0018_0087
manufacturer	String	100	Recommended	Manufacturer
manufacturersmodelname	String	50	Recommended	Manufacturer's model name of the equipment that produced the composite instances. Corresponds to DICOM Tag 0008, 1090 Manufacturers Model Name
matrixcoilmode	Float		Recommended	A method for reducing the number of independent channels by combining in analog the signals from multiple coil elements. There are typically different default modes when using un-accelerated or accelerated (e.g. GRAPPA, SENSE) imaging
multibandaccelerationfactor	Float		Recommended	The multiband factor, for multiband acquisitions.
numberofaverages	Float		Recommended	Number of times a given pulse sequence is repeated before any parameter is changed. ID:DICOM:0018_0083
numberofphaseencodingsteps	Float		Recommended	Total number of lines in k-space in the "y" direction collected during acquisition. ID:DICOM:0018_0089
num_vols_disc_scanner	Float		Recommended	Number of volumes (“dummy scans”) discarded by the scanner (as opposed to those discarded by the user post hoc) before saving the imaging file. For example, a sequence that automatically discards the first 4 volumes before saving would have this field as 4. A sequence that doesn’t discard dummy scans would have this set to 0.
num_vols_disc_user	Float		Recommended	Number of volumes ("dummy scans") discarded by the user before including the file in the dataset. If possible, including all of the volumes is strongly recommended. Please note that the onsets recorded in the _event.tsv file should always refer to the beginning of the acquisition of the first volume in the corresponding imaging file - independent of the value of NumberOfVolumesDiscardedByUser field.
numbershots	Float		Recommended	The number of RF excitations need to reconstruct a slice or volume. Please mind that this is not the same as Echo Train Length which denotes the number of lines of k-space collected after an excitation.
parallelacquisitiontechnique	String	50	Recommended	The type of parallel imaging used (e.g. GRAPPA, SENSE). Corresponds to DICOM Tag 0018, 9078 Parallel Acquisition Technique.
par_red_fact_inplane	Float		Recommended	The parallel imaging (e.g, GRAPPA) factor. Use the denominator of the fraction of k-space encoded for each slice. For example, 2 means half of k-space is encoded. Corresponds to DICOM Tag 0018, 9069 Parallel Reduction Factor In-plane.
partialfourier	String	50	Recommended	The fraction of partial Fourier information collected. Corresponds to DICOM Tag 0018, 9081 Partial Fourier.
patientposition	String	50	Recommended	Description of imaging subject's position relative to the equipment. ID:DICOM:0018_5100
percentphasefieldofview	Float		Recommended	Ratio of field of view dimension in phase direction to field of view dimension in frequency direction, expressed as a percent. ID:DICOM:0018_0094
percentsampling	Float		Recommended	Fraction of acquisition matrix lines acquired, expressed as a percent. ID:DICOM:0018_0093
phaseencodingdirection	String	50	Recommended	Possible values: i, j, k, i-, j-, k-. The letters i, j, k correspond to the first, second and third axis of the data in the NIFTI file. The polarity of the phase encoding is assumed to go from zero index to maximum index unless - sign is present (then the order is reversed - starting from the highest index instead of zero). PhaseEncodingDirection is defined as the direction along which phase is was modulated which may result in visible distortions. Note that this is not the same as the DICOM term InPlanePhaseEncodingDirection which can have ROW or COL values. This parameter is REQUIRED if corresponding fieldmap data is present or when using multiple runs with different phase encoding directions (which can be later used for field inhomogeneity correction).
pixelbandwidth	Float		Recommended	Reciprocal of the total sampling period, in hertz per pixel. ID:DICOM:0018_0095
protocolname	String	50	Recommended	Description of the conditions under which the Series was performed. ID:DICOM:0018_1030
pulsesequencedetails	String	50	Recommended	Information beyond pulse sequence type that identifies the specific pulse sequence used (i.e. "Standard Siemens Sequence distributed with the VB17 software," "Siemens WIP ### version #.##," or "Sequence written by X using a version compiled on MM/DD/YYYY").
pulsesequencetype	String	50	Recommended	A general description of the pulse sequence used for the scan (i.e. MPRAGE, Gradient Echo EPI, Spin Echo EPI, Multiband gradient echo EPI).
receivecoilname	String	50	Recommended	Information describing the receiver coil. Corresponds to DICOM Tag 0018, 1250 Receive Coil Name, although not all vendors populate that DICOM Tag, in which case this field can be derived from an appropriate private DICOM field
repetitiontime	Float		Recommended	The time in seconds between the beginning of an acquisition of one volume and the beginning of acquisition of the volume following it (TR). Please note that this definition includes time between scans (when no data has been acquired) in case of sparse acquisition schemes. This value needs to be consistent with the pixdim[4] field (after accounting for units stored in xyzt_units field) in the NIfTI header. This field is mutually exclusive with VolumeTiming and is derived from DICOM Tag 0018, 0080 and converted to seconds.
scanoptions	String	50	Recommended	Parameters of ScanningSequence. Corresponds to DICOM Tag 0018, 0022 Scan Options.
scanningsequence	String	50	Recommended	Description of the type of data acquired. Corresponds to DICOM Tag 0018, 0020 Scanning Sequence.
sequencename	String	50	Recommended	Manufacturers designation of the sequence name. Corresponds to DICOM Tag 0018, 0024 Sequence Name.
sequencevariant	String	50	Recommended	Variant of the ScanningSequence. Corresponds to DICOM Tag 0018, 0021 Sequence Variant.
sliceencodingdirection	String	50	Recommended	Possible values: i, j, k, i-, j-, k- (the axis of the NIfTI data along which slices were acquired, and the direction in which SliceTiming is defined with respect to). i, j, k identifiers correspond to the first, second and third axis of the data in the NIfTI file. A - sign indicates that the contents of SliceTiming are defined in reverse order - that is, the first entry corresponds to the slice with the largest index, and the final entry corresponds to slice index zero. When present, the axis defined by SliceEncodingDirection needs to be consistent with the ‘slice_dim’ field in the NIfTI header. When absent, the entries in SliceTiming must be in the order of increasing slice index as defined by the NIfTI header.
softwareversions	String	50	Recommended	Manufacturers designation of software version of the equipment that produced the composite instances. Corresponds to DICOM Tag 0018, 1020 Software Versions
taskdescription	String	50	Recommended	Longer description of the task.
taskname	String	50	Recommended	Name of the task. No two tasks should have the same name. Task label (task-) included in the file name is derived from this field by removing all non alphanumeric ([a-zA-Z0-9]) characters. For example task name faces n-back will corresponds to task label facesnback. A RECOMMENDED convention is to name resting state task using labels beginning with rest.
totalreadouttime	Float		Recommended	This is actually the "effective" total readout time , defined as the readout duration, specified in seconds, that would have generated data with the given level of distortion. It is NOT the actual, physical duration of the readout train. If EffectiveEchoSpacing has been properly computed, it is just EffectiveEchoSpacing * (ReconMatrixPE - 1).3 . This parameter is REQUIRED if corresponding "field/distortion" maps acquired with opposing phase encoding directions are present (see 8.9.4).
totalscantimesec	Float		Recommended	Total time of the scan in seconds
transmitcoilname	String	50	Recommended	Name of transmit coil used. ID:DICOM:0018_1251
variableflipangleflag	String	50	Recommended	Flip angle variation applied during image acquisition. ID:DICOM:0018_1315
acq_id	String	50	Recommended	Acquisition ID
run_id	String	50	Recommended	Run ID
session_id	String	20	Recommended	session ID/screening ID
contrast_bolus_ingredient	String	50	Recommended	Active ingredient of agent. Values MUST be one of: IODINE, GADOLINIUM, CARBON DIOXIDE, BARIUM, XENON Corresponds to DICOM Tag 0018,1048.
grad_set_type	String	50	Recommended	It should be possible to infer the gradient coil from the scanner model. If not, e.g. because of a custom upgrade or use of a gradient insert set, then the specifications of the actual gradient coil should be reported independently
mr_transmit_coil_seq	String	50	Recommended	This is a relevant field if a non-standard transmit coil is used. Corresponds to DICOM Tag 0018, 9049 MR Transmit Coil Sequence
partial_fourier_dir	String	50	Recommended	The direction where only partial Fourier information was collected. Corresponds to DICOM Tag 0018, 9036 Partial Fourier Direction.
image_modality	String	20	Recommended	Image modality	MRI; PET; CT; SPECT; ultrasound; FA; X-Ray; spectroscopy; microscopy; DEXA; fNIRS	Computed Radiography; Computed Tomography; External Camera Photography; FA; General Microscopy; MRI; Magnetic Resonance; Magnetic Resonance Spectroscopy; Nuclear Medicine; Single Photon Emission Computed Tomography; Ultrasound
quest_instruct	String	4,000	Recommended	Questionnaire Instructions		Questionnaire Instructions

Data Structure

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Magnetic Resonance Image Quality Metrics