Original Articles

Repeatability and Reproducibility of ADC Measurements and MRI Signal Intensity Measurements of Bone Marrow in Monoclonal Plasma Cell Disorders

A Prospective Bi-institutional Multiscanner, Multiprotocol Study

Wennmann, Markus MD^∗; Thierjung, Heidi MD^∗; Bauer, Fabian^∗,†; Weru, Vivienn MSc^‡; Hielscher, Thomas MSc^‡; Grözinger, Martin MD^∗; Gnirs, Regula^∗; Sauer, Sandra MD^§; Goldschmidt, Hartmut MD^§,∥; Weinhold, Niels PhD^§; Bonekamp, David MD^∗; Schlemmer, Heinz-Peter MD, PhD^∗; Weber, Tim Frederik MD^¶; Delorme, Stefan MD^∗; Rotkopf, Lukas Thomas BSc^∗

Author Information

From the ^∗Division of Radiology, German Cancer Research Center (DKFZ)

^†Medical Faculty, University of Heidelberg

^‡Division of Biostatistics, German Cancer Research Center (DKFZ)

^§Department of Medicine V, Multiple Myeloma Section, University Hospital Heidelberg

^∥National Center for Tumor Diseases (NCT)

^¶Diagnostic and Interventional Radiology, University Hospital Heidelberg, Heidelberg, Germany.

Received for publication July 31, 2021; and accepted for publication, after revision, September 7, 2021.

Conflicts of interest and sources of funding: M.W., H.T., F.B., V.W., T.H., M.G., N.W., T.F.W., S.D., and L.T.R. have nothing to declare. R.G. declared receiving payment for working for HQ Imaging. S.S. reported receiving travel grants or honoraria for presentations from Celgene, Bristol Myers Squibb, Janssen, Takeda, and Amgen. H.G. reported receiving grants and/or provision of investigational medicinal product from Amgen, Bristol Myers Squibb, Celgene, Chugai, Dietmar Hopp Foundation, Janssen, Johns Hopkins University, and Sanofi; receiving research support from Amgen, Bristol Myers Squibb, Celgene, Chugai, Janssen, Incyte, Molecular Partners, Merck Sharp & Dohme, Sanofi, Mundipharma GmbH, Takeda, and Novartis; being on the advisory boards of Adaptive Biotechnology, Amgen, Bristol Myers Squibb, Celgene, Janssen, Sanofi, and Takeda; and receiving honoraria from Amgen, Bristol Myers Squibb, Celgene, Chugai, GlaxoSmithKline, Janssen, Novartis, and Sanofi. D.B. declares receiving payment for lectures from Bayer Vital. H.-P.S. declares receiving consulting fee or honorarium from Siemens, Curagita, Profound, and Bayer; declares receiving travel support from Siemens, Curagita, Profound, and Bayer; is a board member of Curagita; provides consultancy for Curagita and Bayer; declares receiving grants/grants pending from BMBF, Deutsche Krebshilfe, Dietmar Hopp Stiftung, and Roland Ernst Stiftung; and declares receiving payment for lectures from Siemens, Curagita, Profound, and Bayer.

Correspondence to: Markus Wennmann, MD, Division of Radiology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany. E-mail: [email protected].

Supplemental digital contents are available for this article. Direct URL citations appear in the printed text and are provided in the HTML and PDF versions of this article on the journal’s Web site (www.investigativeradiology.com).

Investigative Radiology 57(4):p 272-281, April 2022. | DOI: 10.1097/RLI.0000000000000838

Abstract

Background/Objectives

Apparent diffusion coefficient (ADC) and signal intensity (SI) measurements play an increasing role in magnetic resonance imaging (MRI) of monoclonal plasma cell disorders. The purpose of this study was to assess interrater variability, repeatability, and reproducibility of ADC and SI measurements from bone marrow (BM) under variation of MRI protocols and scanners.

Patients and Methods

Fifty-five patients with suspected or confirmed monoclonal plasma cell disorder were prospectively included in this institutional review board–approved study and underwent several measurements after the standard clinical whole-body MR scan, including repeated scan after repositioning, scan with a second MRI protocol, scan at a second 1.5 T scanner with a harmonized MRI protocol, and scan at a 3 T scanner. For T1-weighted, T2-weighted STIR, B800 images, and ADC maps, regions of interest were placed in the BM of the iliac crest and sacral bone, and in muscle tissue for image normalization. Bland-Altman plots were constructed, and absolute bias, relative bias to mean, limits of agreement, and coefficients of variation were calculated.

Results

Interrater variability and repeatability experiments showed a maximal relative bias of −0.077 and a maximal coefficient of variation of 16.2% for all sequences. Although the deviations at the second 1.5 T scanner with harmonized MRI protocol to the first 1.5 T scanner showed a maximal relative bias of 0.124 for all sequences, the variation of the MRI protocol and scan at the 3 T scanner led to large relative biases of up to −0.357 and −0.526, respectively. When comparing the 3 T scanner to the 1.5 T scanner, normalization to muscle reduced the bias of T1-weighted and T2-weighted sequences, but not of ADC maps.

Conclusions

The MRI scanners with identical field strength and harmonized MRI protocols can provide relatively stable quantitative measurements of BM ADC and SI. Deviations in MRI field strength and MRI protocol should be avoided when applying ADC cutoff values, which were established at other scanners or when performing multicentric imaging trials.

Article Keywords

Keywords
MRI, diffusion-weighted imaging, ADC, multiple myeloma, smoldering multiple myeloma, bone marrow, multicenter, multiscanner, repeatability, reproducibility

Secondary Logo

Journal Logo

Repeatability and Reproducibility of ADC Measurements and MRI Signal Intensity Measurements of Bone Marrow in Monoclonal Plasma Cell Disorders

A Prospective Bi-institutional Multiscanner, Multiprotocol Study