Putaminal hypointensity on T2*-weighted MR imaging is the most practically useful sign in diagnosing multiple system atrophy: A preliminary study.

OBJECTIVE: To identify useful MRI abnormalities in the putamen for diagnosing multiple system atrophy. METHODS: Patients with multiple system atrophy (n=15), Parkinson's disease (n=16), or progressive supranuclear palsy (n=9) and healthy controls (n=10) were enrolled. Using a visual analog scale, 4 examiners independently rated high-intensity signals along the lateral putamen on T2-weighted and T2*-weighted images, low-intensity signals within the putamen on T2-weighted and T2*-weighted images, and putaminal atrophy. Receiver operating characteristic analyses were performed, and the area under the receiver operating characteristic curve was calculated. RESULTS: For differentiating multiple system atrophy from progressive supranuclear palsy, Parkinson's disease, and healthy controls, the mean area under the curve values was the highest for low-intensity signals within the putamen on T2*-weighted images (0.797, 0.867, 0.896, respectively). Variations in the area under the curve values among the 4 examiners were the smallest in low-intensity signals within the putamen on T2*-weighted images. Good inter-rater reliability was achieved for low-intensity signals within the putamen on T2*-weighted images and high-intensity signals along the lateral putamen on T2*-weighted images. CONCLUSION: Low-intensity signals within the putamen on T2*-weighted images is the most useful MRI abnormality for diagnosing multiple system atrophy.

"Bright spotty lesions" on spinal magnetic resonance imaging differentiate neuromyelitis optica from multiple sclerosis.

BACKGROUND: Spinal magnetic resonance imaging (MRI) finding of longitudinally extensive spinal cord lesions (LESCL) extending over three vertebral segments and involvements of spinal central gray matter have been reported in patients with neuromyelitis optica (NMO). OBJECTIVES: We aimed to review spinal MRI findings in NMO and multiple sclerosis (MS), and to determine whether the "bright spotty lesions" (BSLs) are a discriminative finding of NMO. METHODS: For this study, 24 consecutive patients with NMO and 34 patients with MS were enrolled. BSLs were defined as very hyperintense spotty lesions on axial T2WI. We also studied the length, distribution, signal homogeneity, size, and presence of contrast-enhanced lesions. RESULTS: BSLs were more frequently found in patients with NMO (54%) than in those with MS (3%; p < 0.01). LESCL were found in 67% of the NMO patients. BSLs were seen in 63% of the patients without LESCL. BSLs or LESCL were found in 88% of the NMO patients. Inhomogeneous lesions, transversally extensive lesions, and central lesions were more frequently seen in NMO than in MS. CONCLUSIONS: BSLs are a newly defined spinal MRI finding specifically seen in NMO. In combination with LESCL, BSLs can help differentiate patients with NMO from those with MS with higher sensitivity than LESCL alone.

Effects of a polymorphism in the GFAP promoter on the age of onset and ambulatory disability in late-onset Alexander disease.

Alexander disease (AxD) is a rare neurodegenerative disorder. Most patients with AxD have a de novo dominant missense mutation in the glial fibrillary acidic protein (GFAP) gene. Patients with late-onset AxD exhibit a more variable onset and severity than patients with early-onset AxD, suggesting the existence of factors that modify the clinical phenotype of late-onset AxD. A -250-bp C/A single-nucleotide polymorphism (SNP) of the GFAP promoter (rs2070935) in the activator protein-1 binding site is a candidate factor for modification of the clinical phenotype. We analyzed the SNP in 10 patients with late-onset AxD and evaluated the effects of the SNP on the clinical course of late-onset AxD. Three of four cases with the C/C genotype lost the ability to walk in their 30s or 40s, whereas all six cases with the other genotypes retained the ability to walk throughout their 30s. The age of onset in patients with the C/C genotype was significantly earlier than in patients with the other genotypes (P<0.05). A more severe phenotype was observed in the patient in whom the C allele of rs2070935 was in cis with the GFAP mutation compared with the patient in whom the C allele of rs2070935 was in trans with the GFAP mutation. Our investigation revealed the possibility that the C/C genotype at rs2070935 of the GFAP promoter in late-onset AxD was associated with an earlier onset and a more rapid progression of ambulatory disability compared with the other genotypes.

Diffuse and heterogeneous T2-hyperintense lesions in the splenium are characteristic of neuromyelitis optica.

BACKGROUND: Callosal lesions in multiple sclerosis (MS) are usually focal, involving the inferior aspect of the corpus callosum on brain magnetic resonance imaging (MRI), but little is known about callosal lesions in neuromyelitis optica (NMO). OBJECTIVE: To clarify MRI abnormalities in callosal lesions of NMO. METHODS: Japanese patients with NMO (n=28) or MS (n=22) were assessed. The distributions and appearances of callosal lesions were evaluated on a brain mid-sagittal T2-weighted image (T2WI) or a fluid-attenuated inversion recovery image with a 1.5T MRI scanner. Logistic regression analysis identified which characteristics of the callosal lesions were useful for discriminating NMO from MS. RESULTS: Callosal lesions were present in 79% of NMO and 82% of MS patients. Callosal abnormalities of NMO, including splenial lesions (57% in NMO versus 27% in MS, odds ratio (OR)=4.23, p=0.04), diffusely spreading lesions from the lower to upper edges of the corpus callosum (71% versus 23%, OR=7.18, p=0.0024), and heterogeneous T2 hyperintense lesions (71% versus 9%, OR=44.3, p=0.0006), were feasible for discriminating NMO from MS. CONCLUSION: Diffuse and heterogeneous T2 hyperintense splenial lesions were characteristic of NMO. These findings could help distinguish NMO from MS on MRI.

A case of adult-onset alexander disease featuring severe atrophy of the medulla oblongata and upper cervical cord on magnetic resonance imaging.

Adult-onset Alexander disease (AOAD) has been increasingly recognized since the identification of the glial fibrillary acidic protein gene mutation in 2001. We report on a 56-year-old man who was genetically confirmed as AOAD with the glial fibrillary acidic protein mutation of p.M74T. He developed spastic tetraparesis, sensory disturbances in four limbs, and mild cognitive impairment without apparent dysarthria and dysphagia. The case was characterized by severe atrophy of the medulla oblongata and upper cervical cord with intramedullary signal intensity changes on magnetic resonance imaging. While AOAD is diverse in clinical presentation, the peculiar magnetic resonance imaging findings of marked atrophy of the medulla oblongata and cervical cord are thought to be highly suggestive of the diagnosis of AOAD.

Truncal polyradiculopathy due to sarcoidosis.

We report the case of a 43-year-old woman who developed multiple cranial nerve palsy, the symptoms of which included hyposmia, visual loss, facial hypoesthesia, facial weakness, dysphagia, gustatory disturbance, and sensory disturbance of the trunk and ulnar side of the bilateral arms. The clinical features included swelling of the bilateral hilar lymph nodes, uveitis, an elevated serum angiotensin-converting enzyme level, and negative tuberculin reactions, which led to a diagnosis of neurosarcoidosis. Her symptoms improved after administration of steroids. An elevated cerebrospinal fluid cell count and protein level, a low-frequency F-wave and slightly decreased sensory nerve action potentials in bilateral ulnar nerves by nerve conduction studies, and normal findings in the spine by magnetic resonance imaging suggested that truncal hypoesthesia was caused by polyradiculopathy. Although rare, in patients with neurosarcoidosis, truncal polyradiculopathy is noteworthy findings in addition to cranial nerve palsy.