MRI PARAMETERS

Increasing TR does what to scan time?

Increases it.

Increasing TR does what to SNR?

Increases it. Because longitudinal magnetization has more time to recover, more signal is available once flipped to the transverse plane.

Increasing TR has what effect on resolution?

It does not change resolution.

Increasing TR has what effect on SAR?

Increasing TR lowers SAR. More time for cooling between excitations.

Increasing TR has what effect on T1 weighting?

Increasing TR lowers T1 weighting since the vectors have more time to recover longitudinal magnetization. Stronger water vectors are flipped into the transverse plane, setting up for stronger T2 weighting.

Decreasing TR does what to SAR?

Decreasing TR raises SAR, as shorter TRs leave less time for cooling.

Decreasing TR does what to SNR?

Decreasing TR lowers SNR because there is less recovery of transverse magnetization, so less signal is available to be collected once vectors are flipped into transverse plane.

Decreasing TR does what to scan time.

Decreasing TR lowers scan time.

Decreasing TR does what to resolution.

It does not change it.

Decreasing TR does what to T1 weighting?

Decreasing TR increases T1 weighting because fat recovers longitudinal magnetization faster than water, so a stronger fat signal is flipped to the transverse plane than water signal.

Increasing TR has what effect on number of slices?

Increasing TR increases the number of slices able to be encoded as there is more time to record echos before the next TR.

Decreasing TR has what effect on number of slices?

Decreasing TR reduces the number of slices as fewer echos are able to be encoded before the next TR.

Increasing TE has what effect on SNR?

Increasing TE reduces SNR because increasing the amount of time to echo gives more time tor the magnetic moments to dephase, leaving less signal to be collected.

Increasing TE has what effect on scan time?

No direct effect. TR would have to be longer to accommodate fitting the same number of longer TEs in each repetition.

Increasing TE has what effect on resolution?

No effect.

Increasing TE has what effect on SAR?

TE does not effect SAR.

Increasing TE has what effect on T2 weighting?

Increasing TE increased T2 weighting because longer TE allows more time for fat moments to dephase, leaving stronger signal from water.

Increasing TE has what effect on number of slices.

Increasing TE decreases the number of slices that are able to be encoded during a given TR.

Decreasing TE has what effect on SNR?

Decreasing TE increases SNR because magnetic moments have had less time to dephase, leaving more transverse magnetization.

Decreasing TE has what effect on scan time?

No direct impact on scan time. Decreasing TE can indirectly reduce scan time by allowing for a shorter TR.

Decreasing TE has what effect on resolution?

No effect.

Decreasing TE has what effect on SAR?

TE has no effect on SAR.

Decreasing TE has what effect on T2 weighting?

Decreasing TE decreases T2 weighting because less time is allowed for magnetic moments to dephase, leaving strong signals from both fat and water.

Decreasing TE has what effect on number of slices?

Decreasing the TE allows for more slices to be encoded in a given TR period.

Increasing FOV has what effect on SNR?

Increasing the FOV increases SNR as there are more hydrogen atoms producing signal in the field.

Increasing FOV has what effect on scan time?

Increasing FOV does not effect scan time unless the voxel or pixel size remains constant, changing the matrix size.

Increasing the FOV has what effect on spatial resolution.

Increasing the FOV decreases spatial resolution because the pixel size increases.

Increasing FOV has what effect on SAR?

Increasing FOV does not effect SAR.

Increasing FOV has what effect on anatomical coverage.

Increasing FOV increases anatomical coverage.

Decreasing FOV has what effect on SNR?

Decreasing FOV decreases the SNR.

Decreasing FOV has what effect on scan time?

Decreasing FOV does not effect scan time.

Decreasing FOV has what effect on spatial resolution?

Decreasing FOV increases spatial resolution.

Decreasing FOV has what effect on SAR?

Decreasing FOV does not effect SAR.

Increasing the NSA has what effect on SNR?

Increasing NSA raises SNR

Increasing NSA has what effect on scan time?

Scan time increases proportional to the NSA.

Increasing NSA has what effect on spatial resolution?

Increasing NSA has no effect on spatial resolution.

Increasing NSA has what effect on SAR?

Increasing NSA increases SAR.

Increasing NSA has what effect on motion artifact?

Increasing NSA increases chances for motion artifact.

Decreasing NSA has what effect on SNR?

Decreasing NSA decreases SNR.

Decreasing NSA has what effect on scan time?

Decreasing NSA decreases scan time.

Decreasing NSA has what effect on spatial resolution?

Decreasing NSA has no effect on spatial resolution.

Decreasing NSA has what effect on SAR?

Decreasing NSA reduces SAR.

Decreasing NSA has what effect on potential for motion artifact?

Decreasing NSA reduces the potential for motion artifact.

Increasing ETL (or TSE factor) has what effect on SNR?

Increasing ETL (or TSE factor) Reduces SNR as the signal weakens over multiple echos.

Increasing ETL (or TSE factor) Has what effect on on scan time?

Increasing ETL (or TSE factor) Reduces scan time.

Increasing ETL (or TSE factor) Has what effect on spatial resolution?

Increasing ETL (or TSE factor) Has no effect on spatial resolution.

Increasing ETL (or TSE factor)Has what effect on SAR?

Increasing ETL (or TSE factor) Increases SAR as gradients are applied in quicker succession.

Increasing ETL (or TSE factor) Has what effect on potential for blurring?

Increasing ETL (or TSE factor) Increases the potential for blurring.

Decreasing the ETL has what effect on scan time?

Decreasing the ETL Increases the scan time.

Decreasing the ETL Has what effect on spatial resolution?

Decreasing the ETL has no effect on spatial resolution.

Decreasing the ETL has what effect on SAR?

Decreasing the ETL decreases SAR.

Decreasing the ETL has what effect on blurring?

Decreasing the ETL will decrease opportunities for blurring.

Increasing the TI has what effect on SNR?

Increasing the TI reduces the SNR.

Increasing the TI has what effect on scan time?

Increasing the TI increases the scan time due to the increased TR required.

Increasing the TI Has what effect on spatial resolution?

Increasing the TI Has no effect on spatial resolution?

Increasing the TI Has what effect on SAR?

Increasing the TI Has no effect on SAR.

Increasing the TI Has what effect on tissue saturation?

Increasing the TI increases tissue saturation.

Decreasing the TI has what effect on SNR?

Decreasing the TI Increases SNR.

Decreasing the TI Has what effect on scan time?

Decreasing the TI Decreases scan time due to reduced TR.

Decreasing the TI Has what effect on spatial resolution?

Decreasing the TI Has no effect on spatial resolution.

Decreasing the TI Has what effect on SAR?

Decreasing the TI Has no effect on SAR.

Decreasing the TI Has what effect on tissue saturation?

Decreasing TI reduces tissue saturation.

Increasing the phase matrix has what effect on SNR?

Increasing the phase matrix reduces the SNR as smaller pixels contain fewer hydrogen atoms.

Increasing the phase matrix has what effect on scan time?

Increasing the phase matrix increases scan time.

Increasing the phase matrix has what effect on spatial resolution?

Increasing the phase matrix increases spatial resolution.

Increasing the phase matrix has what effect on SAR?

Increasing the phase matrix increases SAR by adding additional TRs from phase encoding steps.

Increasing the phase matrix has what effect on truncation artifacts?

Increasing the phase matrix decreases truncation artifacts.

Decreasing the phase matrix has what effect on SNR?

Decreasing the phase matrix raises SNR as there are more hydrogen atoms per pixel or voxel.

Decreasing the phase matrix has what effect on scan time?

Decreasing the phase matrix decreases scan time due to fewer required TRs.

Decreasing the phase matrix has what effect on spatial resolution?

Decreasing the phase matrix reduces spatial resolution.

Decreasing the phase matrix Has what effect on SAR?

Decreasing the phase matrix lowers SAR because fewer TRs are required.

Decreasing the phase matrix has what effect on truncation artifacts?

Decreasing the phase matrix increases truncation artifacts.

Increasing the flip angle has what effect on SNR?

Increasing the flip angle increases SNR because there is more transverse mag.

Increasing the flip angle has what effect on scan time?

Increasing the flip angle has no effect on scan time.

Increasing the flip angle has what effect on spatial resolution?

Increasing the flip angle has no effect on spatial resolution.

Increasing the flip angle has what effect on SAR?

Increasing the flip angle increases SAR as more RF energy is used to create transverse mag.

Increasing the flip angle has what effect on susceptibility?

Increasing the flip angle reduces susceptibility..

Decreasing the flip angle has what effect on SNR?

Decreasing the flip angle reduces SNR.

Decreasing the flip angle has what effect on scan time?

Decreasing the flip angle has no effect on scan time.

Decreasing the flip angle has what effect on spatial resolution

Decreasing the flip angle has no effect on spatial resolution

Decreasing the flip angle has what effect on SAR?

Decreasing the flip angle reduces Specific Absorption Rate (SAR), minimizing energy deposition in the body.

Decreasing the flip angle has what effect on susceptibility artifact?

Decreasing the flip angle increases susceptibility.

Increasing rBW has what affect on SNR

Increasing receiver bandwidth (rBW) reduces signal-to-noise ratio (SNR) because it broadens the frequency range and can capture more noise.

Increasing rBW has what affect on scan time?

Increasing receiver bandwidth (rBW) reduces scan time by allowing faster data acquisition, as more data can be collected within the same time frame.

Increasing rBW has what affect on spatial resolution?

Increasing receiver bandwidth (rBW) alone has no effect on spatial resolution.

Increasing rBW has what affect on SAR?

Increasing rBW alone has no effect on SAR.

Increasing rBW has what affect on chemical shift and metal artifacts?

Increasing receiver bandwidth (rBW) reduces the chemical shift artifacts and minimizes metal artifacts by allowing for better frequency discrimination.

Decreasing rBW has what affect on SNR?

Decreasing receiver bandwidth (rBW) increases the signal-to-noise ratio (SNR) because it maximizes the signal capture over a narrower frequency range, enhancing the overall image quality.

Decreasing rBW has what affect on scan time?

Decreasing rBW increases scan time as sampling rate is also lowered.

Decreasing rBW has what affect on spatial resolution?

Decreasing rBW has no effect on scan time.

Decreasing rBW has what affect on SAR?

Decreasing rBW has no effect on SAR.

Decreasing rBW has what affect on chemical shift and metal artifacts?

Decreasing rBW increases the severity of chemical shift and metal artifacts, as larger bandwidth can minimize these effects.

Increasing Parallel Imaging (PI) reduction factor has what affect on SNR?

Increasing Parallel Imaging (PI) reduction factor decreases SNR, as it reduces the number of sampled data points and affects image quality.

Increasing Parallel Imaging (PI) reduction factor has what affect on scan time

Increasing Parallel Imaging (PI) reduction factor reduces scan time, as it allows for faster acquisition of images by acquiring fewer data points.

Increasing Parallel Imaging (PI) reduction factor has what affect on spatial resolution?

Increasing Parallel Imaging (PI) reduction factor has no effect effect on spatial resolution.

Increasing Parallel Imaging (PI) reduction factor has what affect on SAR?

Increasing Parallel Imaging (PI) reduction lowers SAR as fewer phase encoding phase encoding gradients are encoded.

Increasing Parallel Imaging (PI) reduction factor has what affect on DWI susceptibility artifacts?

Increasing Parallel Imaging (PI) reduction factor reduces DWI susceptibility artifacts.

Decreasing