Cine IR is a one-click application that uses a 2D FAST GRE pulse sequence with IR-Prepared, Cardiac Gating, and Sequential. Cine IR features a single adiabatic inversion pulse after detection of the cardiac R wave, which precedes the multi-cardiac-phase read-out. Each image (i.e. each cardiac phase) is acquired at a progressively longer TI time.
Use these steps to acquire a cardiac scan that allows you to acquire a fast visualization of tissue contrast at multiple inversion times (TI time) to select an optimal TI for your data set.
Select a GE or Site cardiac protocol with a MDE series.
Acquire a 3-Plane localizer and all other series including long and short axis cine images.
Prior to the MDE series acquisition, from the Workflow Manager, click Add Task > Add Sequence.
From the Protocol screen, select a Cine IR protocol from your site or GE library.
If you cannot locate a Cine IR protocol in either library, then from the Protocol screen:
From the GE protocol library, click the Template tab.
Click the Applications folder.
From the Applications list, click Cine IR and add it to the Multi-Protocol Basket.
Click Accept.
From the Workflow Manager, select the Cine IR series and click Setup. Make scan parameter adjustments, as needed.
Warning
With post-contrast imaging using inversion-prepared pulse sequences, there is a potential that lesion conspicuity may be reduced and some lesions may not be apparent in comparison to T1-weighted spin-echo imaging.
From the Cardiac Gating tab, enter a RR interval that matches the RR interval used for the MDE scan. Typically, use the following:
For heart rates lower than 55 BPM, use 1 RR.
For heart rates in the range of 55-100 BPM, use 2 RR, which improves SNR compared to 1 RR.
For heart rates in the range of 100-120 BPM, use 3 RR.
For heart rates above 120 BPM, use 4 RR.
For the Cine IR scan, use a low flip angle of 5°.
Graphically prescribe a short axis scan to visualize myocardium.
Click the Advanced tab and select User CV values, if needed.
From the AutoView screen, review the images and note the TI time of each image. The Cine IR images provide an evolution of T1-contrast based on the TI time of each phase. Select the TI of the image that demonstrates the optimal myocardium contrast that can be used for the MDE scan.
Figure 1. Example of Cine IR images
Table 1. Image legend
Number
Description
1
TI is too short.
2
Bounce point artifact.
3
Optimal TI value.
4
TI is too long.
Note: the optimal inversion time (TI) that displays nulled normal myocardium signal. In the example above, the optimum TI is 400 ms. Use this TI time for the 2D MDE scan.
Beware of the bounce point artifact, that indicates the TI is shorter than optimal. It is caused by signal cancellation at the tissue/blood interface. The bounce point artifact looks like a black outline along the endocardial and epicardial borders. Avoid this by choosing a higher TI.
Typically, a MDE (FGRE, cardiac gated, IR-Prep) scan is acquired for cardiac exams to asses myocardial viability.
Figure 2. Arrows point to abnormal myocardium that has high signal intensity
Cine IR uses a multi-phase Fastcard/FastCINE scan where each phase represents a different TI and one image is generated for each phase. The TI time is annotated on each image.
Figure 3. Cine IR is a multi-phase acquisition
Table 2. Cine IR image legend
Number
Description
1
IR Prep pulse
2
Data acquisition where one phase is one image
3
Time
Selecting the optimum TI for the MDE scan is critical to enhance differences in the myocardium.
TI selection varies from patient to patient based on circulatory status, renal function, cardiac output and disease state.
Improper selection can lead to sub-optimal image contrast and potentially result in a repeat MDE scan.
Considerations
Acquire the Cine IR scan once, immediately before the 2D MDE scan, approximately 8 minutes post-contrast injection for late enhancement.
From the Cardiac tab, select the same #RR for both the Cine IR and the 2D MDE scans.