Back

Evaluating Non-Negative Matrix Underapproximation for the Analysis of Long Echo Time Magnetic Resonance Spectroscopy Data in Human Brain Tumors

Ungan, G.; Vellido, A.; Julia-Sape, M.

2025-06-14 radiology and imaging
10.1101/2025.06.13.25329582 medRxiv
Show abstract

Magnetic Resonance Spectroscopy (MRS) provides metabolic profiles for brain tumor classification but its use for analytical purposes is hindered by spectral variability and data sparsity. This study compares the performance of several Non-Negative Matrix Underapproximation (NMU) methods, namely Sparse NMU (S-NMU), Global NMU (G-NMU), and Recursive NMU (R-NMU) to that of Convex Non-Negative Matrix Factorization (C-NMF) for the purpose of feature extraction from for Long Echo (LE) MRS. Using a multicenter dataset, such performance in the task of classifying several tumor types was evaluated using Balanced Error Rate (BER), ANOVA, and post-hoc statistical tests. Results show that C-NMF consistently outperforms NMU in LE-MRS, achieving the lowest BER, particularly in distinguishing high-grade from low-grade tumors. While NMU methods excel in localized spectral decomposition, their advantages, previously demonstrated in short-echo MRS, are less pronounced in LE-MRS. These findings establish C-NMF as the most effective method for spectral feature extraction in LE-MRS-based tumor classification.

Matching journals

The top 8 journals account for 50% of the predicted probability mass.

50% of probability mass above

"Similar papers" are the closest papers from that journal in the model's embedding space. They show what the match is built on, but the ranking comes mostly from a classifier over the whole training set, not from these examples alone.