Hyperintense Dentate Nuclei on T1-Weighted MRI: Relation to Repeat Gadolinium Administration

Abstract

BACKGROUND AND PURPOSE A hyperintense appearance of the dentate nucleus on T1-weighted MR images has been related to various clinical conditions, but the etiology remains indeterminate. We aimed to investigate the possible associations between a hyperintense appearance of the dentate nucleus on T1-weighted MR images in patients exposed to radiation and factors including, but not limited to, the cumulative number of contrast-enhanced MR images, amount of gadolinium administration, dosage of ionizing radiation, and patient demographics. MATERIALS AND METHODS The medical records of 706 consecutive patients who were treated with brain irradiation at The Johns Hopkins Medical Institutions between 1995 and 2010 were blindly reviewed by 2 readers. RESULTS One hundred eighty-four subjects were included for dentate nuclei analysis. Among the 184 subjects who cumulatively underwent 2677 MR imaging studies following intravenous gadolinium administration, 103 patients had hyperintense dentate nuclei on precontrast T1-weighted MR images. The average number of gadolinium-enhanced MR imaging studies performed in the group with normal dentate nuclei was significantly lower than that of the group with hyperintense dentate nuclei. The average follow-up time was 62.5 months. No significant difference was observed between hyperintense and normal dentate nuclei groups in terms of exposed radiation dose, serum creatinine and calcium/phosphate levels, patient demographics, history of chemotherapy, and strength of the scanner. No dentate nuclei abnormalities were found on the corresponding CT scans of patients with hyperintense dentate nuclei (n = 44). No dentate nuclei abnormalities were found in 53 healthy volunteers. CONCLUSIONS Repeat performance of gadolinium-enhanced studies likely contributes to a long-standing hyperintense appearance of dentate nuclei on precontrast T1-weighted-MR images.

Gadolinium-Based Contrast Agent Accumulation and Toxicity: An Update

“…23 Similar findings were also reported with brain irradiation. 24 From the perspective of our current understanding, none of these studies considered the number of contrast-enhanced MR imaging studies performed in their analyses, raising the question of whether these findings reflect gadolinium deposition rather than a primary disease manifestation, as demonstrated recently by Adin et al 25 in a study with 184 subjects who were treated with brain irradiation.…”

T1 Signal-Intensity Increase in the Dentate Nucleus after Multiple Exposures to Gadodiamide: Intraindividual Comparison between 2 Commonly Used Sequences

“…[1][2][3][4][5][6][7][8][9][10][11] One major limitation of retrospective human studies of gadolinium deposition is the variability of the MR imaging protocols used, according to the pathology that is being studied and among different institutions.…”

“…8 It is generally assumed that visual analysis correlates well with quantitative analysis, but qualitative assessment of the presence or absence of hyperintensity on T1-weighted MR images is subjective; hence, quantitative signal-intensity measurement is commonly favored. In most of the published literature, the authors have used T1-weighted SE sequences to quantitatively evaluate the signal intensity and signal changes with time.…”

“…Kanda et al 5 and Adin et al 8 used qualitative measurements to evaluate signal-intensity changes in patients who underwent multiple GBCA administrations, by using T1-weighted spin-echo (SE), 5,8 T1 MPRAGE, or T1 FLAIR images. 8 It is generally assumed that visual analysis correlates well with quantitative analysis, but qualitative assessment of the presence or absence of hyperintensity on T1-weighted MR images is subjective; hence, quantitative signal-intensity measurement is commonly favored.…”

Technical aspects of MRI signal change quantification after gadolinium-based contrast agents' administration

“…However, in some quantitative [4,7,13], and qualitative [13,15] studies, different T1-weighted sequences have been interchangeably used, including T1 SE, T1-weighted three-dimensional magnetization-prepared rapid gradient-echo (3D MPRAGE) [4], T1 FLASH (fast low-angle shot) [7], and T1 fluid attenuation inversion recovery (FLAIR) [15]. Recognizing this potential confounding factor, Radbruch et al [4] performed a subgroup analysis to examine whether the two different T1-weighted sequences applied (MPRAGE and SE) had an influence on the signal intensity ratio difference.…”