Real-world data have shown variability in treatment responses to nusinersen in spinal muscular atrophy (SMA). We investigated whether the magnitude of muscle impairment assessed by magnetic resonance imaging (MRI) at baseline can predict the treatment response. We retrospectively assessed the clinical data in relevance to the thigh and pelvic MRI taken before the nusinersen treatment. A total of 16 patients with SMA types 2 and 3 (age = mean [SD]; 9.2 [4.6] year) receiving nusinersen treatment were enrolled. The T1-weighted MRI images of the pelvis and thigh were scored for muscle fatty infiltration and atrophy. The minimally clinically important difference (MCID) was considered as gaining at least 3 points of Hammersmith Functional Motor Scale-Expanded (HFMSE) from baseline. Of these 16 individuals, 14 had been treated for at least 15 months with baseline data. At 15 months, seven individuals obtained MCID in HFMSE. Baseline muscle MRI score could not differentiate the two groups; however, individuals who obtained MCID had significantly less severe scoliosis. In addition, there was a significant and negative relationship between baseline MRI score and the change of score in HFMSE after 15 months of treatment. Further, baseline Cobb angle along with MRI score also indicated the correlation to the degree of change in motor function. The degree of muscle damage may confer the variability in response to nusinersen in SMA types 2 and 3. Muscle MRI score along with the severity of scoliosis assessed at baseline may help to predict the motor function change.

Introduction: Tau protein accumulation in the brain is thought to be one of the causes of progressive supranuclear palsy (PSP). The glymphatic system was discovered a decade ago as a waste drainage system in the brain that promotes the elimination of amyloid-beta and tau protein. We here evaluated the relationships between glymphatic system activity and regional brain volumes in PSP patients. Method: Subjects were 24 patients with PSP and 42 healthy participants who underwent diffusion tensor imaging (DTI). We computed the diffusion tensor image analysis along the perivascular space (DTI-ALPS) index as a proxy of glymphatic system activity and estimated the relationships between the DTI-ALPS index and regional brain volume in PSP patients by whole-brain and region-of-interest analyses, including analyses of the midbrain and third and lateral ventricles. Results: The DTI-ALPS index was significantly lower in patients with PSP compared with healthy subjects. Further, there were significant correlations between the DTI-ALPS index and the regional brain volumes in the midbrain tegmentum, pons, right frontal lobe, and lateral ventricles in patients with PSP. Conclusions: Our data suggest that the DTI-ALPS index is a good biomarker for PSP and might be effective to distinguish PSP from other neurocognitive disorders.

Recent developments in image analysis have enabled an individual’s brain network to be evaluated and brain age to be predicted from gray matter images. Our study aimed to investigate the effects of age and sex on single-subject gray matter networks using a large sample of healthy participants. We recruited 812 healthy individuals (59.3 ± 14.0 years, 407 females, and 405 males) who underwent three-dimensional T1-weighted magnetic resonance imaging. Similarity-based gray matter networks were constructed, and the following network properties were calculated: normalized clustering, normalized path length, and small-world coefficients. The predicted brain age was computed using a support-vector regression model. We evaluated the network alterations related to age and sex. Additionally, we examined the correlations between the network properties and predicted brain age and compared them with the correlations between the network properties and chronological age. The brain network retained efficient small-world properties regardless of age; however, reduced small-world properties were observed with advancing age. Although women exhibited higher network properties than men and similar age-related network declines as men in the subjects aged < 70 years, faster age-related network declines were observed in women, leading to no differences in sex among the participants aged ≥ 70 years. Brain age correlated well with network properties compared to chronological age in participants aged ≥ 70 years. Although the brain network retained small-world properties, it moved towards randomized networks with aging. Faster age-related network disruptions in women were observed than in men among the elderly. Our findings provide new insights into network alterations underlying aging.

BACKGROUND AND PURPOSE: CNS lesions of tuberous sclerosis complex are diagnosed mainly by T2WI, FLAIR, and sometimes T1WI with magnetization transfer contrast. The usefulness of T1WI with chemical shift selective images was recently reported in focal cortical dysplasia type IIb, which has histopathologic and imaging features similar to those of tuberous sclerosis complex. We investigated the usefulness of the T1WI with chemical shift selective images in detecting CNS lesions of tuberous sclerosis complex. MATERIALS AND METHODS: We retrospectively reviewed 25 consecutive patients with tuberous sclerosis complex (mean age, 11.9 [SD, 8.9] years; 14 males) who underwent MR imaging including T1WI, T1WI with magnetization transfer contrast, T1WI with chemical shift selective, T2WI, and FLAIR images. Two neuroradiologists assessed the number of CNS lesions in each sequence and compared them in 2 steps: among T1WI, T1WI with magnetization transfer contrast and T1WI with chemical shift selective images, and among T2WI, FLAIR, and T1WI with chemical shift selective images. We calculated the contrast ratio of the cortical tubers and of adjacent normal-appearing gray matter and the contrast ratio of radial migration lines and adjacent normal-appearing white matter in each sequence and compared them. RESULTS: T1WI with chemical shift selective images was significantly superior to T1WI with magnetization transfer contrast for the detection of radial migration lines and contrast ratio of radial migration lines. There was no significant difference between T1WI with chemical shift selective images and T1WI with magnetization transfer contrast for the detection of cortical tubers and the contrast ratio of the cortical tubers. Both T2WI and FLAIR were statistically superior to T1WI with chemical shift selective images for the detection of cortical tubers. T1WI with chemical shift selective images was significantly superior to T2WI and FLAIR for the detection of radial migration lines. CONCLUSIONS: The usefulness of T1WI with chemical shift selective images in detecting radial migration lines was demonstrated. Our findings suggest that the combination of T1WI with chemical shift selective images, T2WI, and FLAIR would be useful to evaluate the CNS lesions of patients with tuberous sclerosis complex in daily clinical practice.

Alzheimer’s disease (AD), the most common type of dementia in elderly individuals, slowly and progressively diminishes the cognitive function. Mild cognitive impairment (MCI) is also a significant risk factor for the onset of AD. Magnetic resonance imaging (MRI) is widely used for the detection and understanding of the natural progression of AD and other neurodegenerative disorders. For proper assessment of these diseases, a reliable database of images from cognitively healthy participants is important. However, differences in magnetic field strength or the sex and age of participants between a normal database and an evaluation data set can affect the accuracy of the detection and evaluation of neurodegenerative disorders. We developed a brain segmentation procedure, based on 30 Japanese brain atlases, and suggest a harmonized Z-score to correct the differences in field strength and sex and age from a large data set (1235 cognitively healthy participants), including 1.5 T and 3 T T1-weighted brain images. We evaluated our harmonized Z-score for AD discriminative power and classification accuracy between stable MCI and progressive MCI. Our procedure can perform brain segmentation in approximately 30 min. The harmonized Z-score of the hippocampus achieved high accuracy (AUC = 0.96) for AD detection and moderate accuracy (AUC = 0.70) to classify stable or progressive MCI. These results show that our method can detect AD with high accuracy and high generalization capability. Moreover, it may discriminate between stable and progressive MCI. Our study has some limitations: the age groups in the 1.5 T data set and 3 T data set are significantly different. In this study, we focused on AD, which is primarily a disease of elderly patients. For other diseases in different age groups, the harmonized Z-score needs to be recalculated using different data sets.

Hemochromatosis is a primary or secondary pathological condition characterized by the deposition of excess iron in the body tissues, which can eventually lead to cellular damage and organ dysfunction. Although excess iron deposition in the central nervous system is rare, involvement of the choroid plexus, pituitary gland, cortical surfaces, and basal ganglia has been reported to date. This case report describes 2 cases of transfusion-induced hemochromatosis involving the choroid plexus and pituitary gland, which were diagnosed by magnetic resonance imaging (MRI). In both cases, gradient echo (GRE) sequences, such as T2 star-weighted image and susceptibility-weighted imaging demonstrated markedly low signal intensity in the choroid plexus. Furthermore, the pituitary gland showed low signal intensity on T2-weighted images in Patient 2. Because these low signal intensities were not seen prior to red blood cell transfusion, they were diagnosed with transfusion-induced hemochromatosis. Brain MRI with GRE sequences was useful in detecting iron deposition in the choroid plexus. Considering that iron deposition in the body tissues can lead to irreversible organ damage, MRI with GRE sequences should be considered for patients with suspected iron overload.