Magnetic resonance spectroscopy in pediatric brain tumors: how to make a more confident diagnosis

Abstract

Background: Non-invasive diagnosis of pediatric brain tumors can be challenging due to diverse tumor pathologies and similar imaging appearances. Magnetic resonance spectroscopy (MRS), when combined with high spatial resolution anatomic imaging obtained with conventional magnetic resonance imaging (MRI), provides metabolic information within the lesion as well as the surrounding tissue. The differentiation of neoplastic from non-neoplastic lesions and low-grade from high-grade neoplasms is essential for determining the choice of treatment and the best treatment plan. We aimed to measure specific metabolic ratios and evaluate metabolic profiles of various lesions by MRS to assist in making a more confident diagnosis. Results: The choline/creatine (Cho/Cr), choline/N-acetylaspartate (Cho/NAA), and Cho/NAA+Cr ratios all had statistically significant values for the differentiation between neoplastic and non-neoplastic lesions at cutoffs 1.8, 2, and 0.8 respectively. The Cho/NAA, Cho/Cr, Cho/NAA+Cr, and myo-inositol/creatine (mI/Cr) ratios all had statistically significant values for the differentiation of high-grade from low-grade neoplasms at cutoffs 3.3, 3.5, 1.3, and 1.5 respectively. The presence of a lipid lactate peak was only significant for differentiating high-grade from low-grade neoplasms. Medulloblastomas, diffuse pontine gliomas, and choroid plexus carcinoma all showed characteristic metabolic profiles on MRS. Metastasis showed lower Cho/ NAA and Cho/Cr ratios outside the tumor margin than high-grade neoplasms. Conclusion: The use of certain metabolite ratios with high sensitivity and specificity to distinguish neoplastic from nonneoplastic lesions and low-grade from high-grade neoplasms while assessing the metabolic profile of the lesion aids in the non-invasive diagnosis of pediatric brain tumors. MRS facilitates earlier treatment planning by determining tumor spatial extent and predicting tumor behavior with potential to solve sampling problems of inaccessible and heterogenous lesions as well as unnecessary sampling of benign lesions.

Magnetic Resonance Spectroscopy Role in Assessment of Pediatric Supratentorial Brain Lesions

“…At short TE, mI/Cr ratio of 1.15 was tested as a cut value for diagnosing tumor with sensitivity [100%] and specificity [95%]. Attia et al [3] reported an increase of choline and reduction of NAA at the long TE. This suggested that a larger loss of neuron function and larger membrane turnover characterizes the neoplastic than nonneoplastic processes.…”

“…It was considered the corner-stone for the diagnosis of brain tumors in many cases. However, confident differentiation of neoplastic from non-neoplastic brain lesions or low from high-grade tumors is problematic with conventional MRI [3] .…”

“…The non-invasive accurate diagnosis and differentiating tumorous from non-tumorous brain lesions of the children, as well as differentiating the low from the high-grade tumors is crucial in the construction of the correct treatment plan. MRS provides valuable data about biochemical characteristics, metabolic composition of the lesions and the surrounding structures [3] . Proton [ 1 H-MRS] can guide the clinical decision-making in pediatric neuro-oncology, by the introduction of the valuable information, not obtained by the conventional imaging.…”

Magnetic Resonance Spectroscopy: Role in clinical decision making and accurate diagnosis of the brain lesions

“…It is evident that MRS provides information necessary for differentiating, tuberculosis, lowgrade and high-grade gliomas, brain abscess and many more. Several previous studies have been carried out to investigate the sensitivities and specificities of various metabolite ratios for diagnosing and differentiating various brain lesions 11,12 . Onyambu et al studied the use of MR spectroscopy and its assistance to the radiologist in diverse clinical presentations 13 .…”

Artificial Intelligence and Precision Medicine: A New Frontier for the Treatment of Brain Tumors

“…Pathology is the key to understanding and diagnosing cancer [ 142 , 143 ]. Therefore, it is essential to obtain an accurate diagnosis to determine the best treatment plan [ 144 ]. That is why ultrasounds need image classification and object recognition algorithms that use deep learning to obtain precise results.…”