Calcification Mimicking Manganese-Induced Increased Signal Intensities in T1-Weighted MR Images in a Patient Taking Herbal Medicine: Case Report
Section snippets
INTRODUCTION
The manganese ion (Mn2+) has five unpaired electrons in the 3d orbit, which results in its large magnetic moment, causing the shortening of T1-relaxation time and an increase in signal intensity on T1-weighted magnetic resonance images (MRI). Because of the paramagnetic quality of Mn, a bilateral symmetrical increase in signal intensities, confined to the globus pallidus and midbrain, can be observed on T1-weighted MRI, but with no alteration on the T2-weighted image. Characteristic high signal
CASE REPORT
A 39-year-old woman was admitted with mutism and involuntary movements which had developed the day before. She was alert and cooperative, but could not speak. Her eyes were blinking, and her head was nodding at an interval of 10–30 s. Neurologic examination showed no focal neurologic deficits. She began to speak the next day, but she could not recall what she had done 2 days before. Laboratory tests such as glucose, urea nitrogen, calcium, liver function tests, and complete blood cell counts
DISCUSSION
The increased signals in T1-weighted MRI without corresponding alterations on the T2-weighted image, which were first presumed to be induced by Mn, were concluded to be due to calcification based on the following reasons.
First, follow-up brain MRI at an interval of 11 months did not show any interval change. The Mn-induced high signals in MRI usually disappear within 6 months or 1 year following the withdrawal from the source of Mn accumulation (Newland et al., 1989, Nelson et al., 1993, Huang
References (28)
- et al.
Manganese intoxication during total parenteral nutrition
Lancet
(1992) - et al.
Manganese and chronic hepatic encephalopathy
Lancet
(1995) - et al.
Visualizing manganese in the primate basal ganglia with magnetic resonance imaging
Exp. Neurol.
(1989) - et al.
Pharmacokinetic data needs to support risk assessments for inhaled and ingested manganese
NeuroToxicology
(1999) - et al.
Calcified intracranial lesions: detection with gradient-echo-acquisition rapid MR imaging
Am. J. Roentgenol.
(1988) - Baldwin S, Deaker M, Maher W. Low volume microwave digestion of marine biological tissues for the measurement of trace...
- et al.
Hyperintense disks on T1-wighted MR images: correlation with calcification
Raidiology
(1995) - et al.
Schizophrenia and familial idiopathic basal ganglia calcification: a case report
Psychol. Med.
(2001) - et al.
Physiologic intracranial calcification with hyperintensity on MR imaging: case report and experimental model
Am. J. Neuroradiol.
(1988) - et al.
Determination of manganese in biological materials by electrothermal atomic absorption spectrometry, a review
Clin. Chem.
(1988)
Intracranial hematomas: imaging by high-field MR
Radiology
Choroidal melanomas: correlation of NMR spectroscopy and MR imaging
Radiology
Manganese intoxication and chronic liver failure
Ann. Neurol.
High signal intensity in MR images of calcified brain tissue
Radiology
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