Assessment of Melanin Content and its Influence on Susceptibility Contrast in Melanoma Metastases

Purpose To quantify the influence of melanin content on magnetic susceptibility of cerebral melanoma metastases. Methods Patients with non-hemorrhagic metastases were included based on the absence of susceptibility blooming artifacts. Susceptibility maps were calculated from 3D gradient echo data, u...

Full description

Saved in:
Bibliographic Details
Published in:Clinical neuroradiology (Munich) 2020-09, Vol.30 (3), p.607-614
Main Authors: Straub, Sina, Laun, Frederik B., Freitag, Martin T., Kölsche, Christian, von Deimling, Andreas, Denoix, Michael, Bendszus, Martin, Schlemmer, Heinz-Peter, Ladd, Mark E., Schneider, Till M.
Format: Article
Language:English
Subjects:
Algorithms
Free radicals (Chemistry)
Medical imaging equipment
Medicine
Medicine & Public Health
Melanoma
Metastasis
Neurology
Neuroradiology
Neurosurgery
Original Article
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Purpose To quantify the influence of melanin content on magnetic susceptibility of cerebral melanoma metastases. Methods Patients with non-hemorrhagic metastases were included based on the absence of susceptibility blooming artifacts. Susceptibility maps were calculated from 3D gradient echo data, using Laplacian-based phase unwrapping, sophisticated harmonic artefact reduction for phase data (V-SHARP) with varying spherical kernel sizes for background field removal and the iLSQR algorithm for the inversion of phase data. Susceptibility maps were referenced to cerebrospinal fluid. Non-hemorrhagic metastases were identified on contrast-enhanced T1-weighted images and susceptibility weighted images. Metastases masks were drawn on T1-weighted post-contrast images and used to compute mean susceptibility values of each metastasis. Results A total of 33 non-hemorrhagic melanoma brain metastases in 20 patients were quantitatively evaluated. Metastases without and with hyperintense signal on T1-weighted images, which corresponds to the melanin content, showed median susceptibility values of −0.028 ppm and −0.020 ppm, respectively. The susceptibility differences between metastases without and with T1-weighted hyperintense signal was not statistically significant ( p  ≥ 0.05). Conclusion Non-hemorrhagic cerebral melanoma metastases showed weak diamagnetic susceptibility values and susceptibility did not significantly correlate to T1-weighted signals. Therefore, melanin does not seem to be a major contributor to susceptibility in cerebral melanoma metastases.
ISSN:1869-1439
1869-1447
DOI:10.1007/s00062-019-00816-x