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Transit time corrected arterial spin labeling technique aids to overcome delayed transit time effect
Tae Jin Yun1,2, Chul-Ho Sohn3,4, Roh-Eul Yoo1,2
1Institute of Radiation Medicine, Seoul National University Medical Research Center, Seoul, Republic of Korea.
Neuroradiology
|December 31, 2017
Summary
Multi-phase arterial spin labeling MR perfusion imaging (ASL-MRP) with transit time correction improves cerebral blood flow (CBF) map accuracy. This technique overcomes delays seen in conventional ASL-MRP, offering more reliable perfusion assessments.
Area of Science:
- Radiology
- Neuroimaging
- Medical Physics
Background:
- Cerebral blood flow (CBF) assessment is crucial for diagnosing and monitoring various neurological conditions.
- Arterial spin labeling MR perfusion imaging (ASL-MRP) offers a non-invasive method for quantifying CBF.
- Conventional ASL-MRP techniques can be affected by transit time delays, potentially impacting accuracy.
Purpose of the Study:
- To evaluate the clinical utility of transit time corrected CBF maps derived from multi-phase ASL-MRP.
- To compare the accuracy of multi-phase ASL-MRP derived CBF maps against dynamic susceptibility contrast MR perfusion imaging (DSC-MRP).
Main Methods:
- A retrospective analysis of 108 patients undergoing both conventional and multi-phase ASL-MRP, alongside DSC-MRP.
- Vascular territory-based analysis of CBF and time to peak (TTP) maps.
- Bland-Altman analysis to assess concordance between normalized CBF (nCBF) values from different ASL-MRP techniques and DSC-MRP.
- Regression analysis to determine the dependence of nCBF differences on TTP.
Main Results:
- Multi-phase ASL-MRP with transit time correction showed improved concordance with DSC-MRP compared to conventional ASL-MRP.
- The difference in nCBF values between DSC-MRP and conventional ASL-MRP was dependent on TTP.
- No significant dependence of nCBF differences on TTP was observed for the multi-phase ASL-MRP technique.
Conclusions:
- Transit time corrected CBF maps from multi-phase ASL-MRP effectively mitigate the impact of delayed transit times.
- This advanced ASL-MRP technique enhances the reliability of perfusion imaging in clinical practice.
- Multi-phase ASL-MRP represents a valuable advancement for accurate non-invasive CBF quantification.
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