Automatic T2* determination for quantification of iron load in heart and liver: a comparison between automatic inline Maximum Likelihood Estimate and the truncation and offset methods. (16th October 2015)

• Record Type: Journal Article
• Authors: Hedström, Erik; Voigt, Tobias; Greil, Gerald; Schaeffter, Tobias; Nagel, Eike
• Is Part Of: Clinical physiology and functional imaging. Volume 37:Number 3(2017:May)
• Page Start: 299
• Page End: 304
• Publication Date: 2015-10-16
• Subjects: algorithm -- automated -- heart -- ironload -- liver -- validation; Physiology, Pathological -- Periodicals; Diagnostic imaging -- Periodicals; 612
• DOI: 10.1111/cpf.12303
• Languages: English
• ISSNs: 1475-0961

Abstract

Summary: Purpose: To validate ironload T2* by automatic inline Maximum Likelihood Estimate (MLE) with k‐space Rician noise correction, against the manual and automated truncation, as well as offset methods, in phantoms and in heart and liver in patients. Methods: Twenty‐five patients and an iron‐oxide phantom were scanned at 1.5T using 2 multi‐echo gradient‐echo sequences. All parameters were identical (voxel 2–3 × 2–3 × 10 mm 3, 10 echoes, TR = 26 ms, FA = 20°, BW = 833 Hz, SENSE = 2) except for TE (cardiac: TE1 = 2·5 ms, ΔTE = 2·5 ms; liver: TE1 = 1·2 ms, ΔTE = 1·5 ms). Phantoms were scanned at 1 and 32 signal averages (NSA), with NSA32 representing low‐noise reference. Results: Phantoms: MLE showed low variability between NSA1 and NSA32 (0·02 ± 0·29 ms, CI ±0·21 ms). Between methods, no difference was shown (MLE versus all: <0·31 ms, CI < ±0·35 ms). Patients: No differences were found between methods in heart (MLE versus all: <−0·22 ms, CI < ±0·75 ms) or liver (MLE versus all: <0·12 ms, CI < ±0·26 ms). Conclusions: The automatic inline MLE method is comparable to the general reference standards for determining cardiac and liver T2* for ironload in man. An automatic inline method may simplify ironload assessment, particularly in centres seeing fewer cases.