Altered Brain Glymphatic Flow at Diffusion-Tensor MRI in Rapid Eye Movement Sleep Behavior Disorder.

Background Brain glymphatic dysfunction may contribute to the development of α-synucleinopathies. Yet, noninvasive imaging and quantification remain lacking. Purpose To examine glymphatic function of the brain in isolated rapid eye movement sleep behavior disorder (RBD) and its relevance to phenoconversion with use of diffusion-tensor imaging (DTI) analysis along the perivascular space (ALPS). Materials and Methods This prospective study included consecutive participants diagnosed with RBD, age- and sex-matched control participants, and participants with Parkinson disease (PD) who were enrolled and examined between May 2017 and April 2020. All study participants underwent 3.0-T brain MRI including DTI, susceptibility-weighted and susceptibility map-weighted imaging, and/or dopamine transporter imaging using iodine 123-2ß-carbomethoxy-3ß-(4-iodophenyl)-N-(3-fluoropropyl)-nortropane SPECT at the time of participation. Phenoconversion status to α-synucleinopathies was unknown at the time of MRI. Participants were regularly followed up and monitored for any signs of α-synucleinopathies. The ALPS index reflecting glymphatic activity was calculated by a ratio of the diffusivities along the x-axis in the projection and association neural fibers to the diffusivities perpendicular to them and compared according to the groups with use of the Kruskal-Wallis and Mann-Whitney U tests. The phenoconversion risk in participants with RBD was evaluated according to the ALPS index with use of a Cox proportional hazards model. Results Twenty participants diagnosed with RBD (12 men; median age, 73 years [IQR, 66-76 years]), 20 control participants, and 20 participants with PD were included. The median ALPS index was lower in the group with RBD versus controls (1.53 vs 1.72; P = .001) but showed no evidence of a difference compared with the group with PD (1.49; P = .68). The conversion risk decreased with an increasing ALPS index (hazard ratio, 0.57 per 0.1 increase in the ALPS index [95% CI: 0.35, 0.93]; P = .03). Conclusion DTI-ALPS in RBD demonstrated a more severe reduction of glymphatic activity in individuals with phenoconversion to α-synucleinopathies. © RSNA, 2023 Supplemental material is available for this article. See also the editorial by Filippi and Balestrino in this issue.

Glymphatic system evaluation using diffusion tensor imaging in patients with traumatic brain injury.

PURPOSE: Glymphatic system dysfunction has been reported in animal models of traumatic brain injury (TBI). This study aimed to evaluate the activity of the human glymphatic system using the non-invasive Diffusion Tensor Image-Analysis aLong the Perivascular Space (DTI-ALPS) method in patients with TBI. METHODS: A total of 89 patients with TBI (June 2018 to May 2020) were retrospectively enrolled, and 34 healthy volunteers were included who had no previous medical or neurological disease. Magnetic resonance imaging (MRI) with DTI was performed, and the ALPS index was calculated to evaluate the glymphatic system's activity. Wilcoxon rank-sum test was used to compare the ALPS index between patients with TBI and healthy controls. ANOVA was done to compare the ALPS index among controls and patients with mild/moderate-to-severe TBI. Multivariate logistic regression analyses were used to identify independent clinical and radiological factors associated with the ALPS index. The correlation between Glasgow Coma Scale (GCS) score and the ALPS index was also assessed. RESULTS: The ALPS index was significantly lower in patients with TBI than in healthy controls (median, 1.317 vs. 1.456, P < 0.0001). There were significant differences in the ALPS index between healthy controls and patients with mild/moderate-to-severe TBI (ANOVA, P < 0.001). The presence of subarachnoid hemorrhage (P = 0.004) and diffuse axonal injury (P = 0.001) was correlated with a lower ALPS index in the multivariate analysis. There was a weak positive correlation between the ALPS index and GCS scores (r = 0.242, P = 0.023). CONCLUSIONS: The DTI-ALPS method is useful for evaluating glymphatic system impairment and quantifying its activity in patients with TBI.

Deep learning regressor model based on nigrosome MRI in Parkinson syndrome effectively predicts striatal dopamine transporter-SPECT uptake.

PURPOSE: Nigrosome imaging using susceptibility-weighted imaging (SWI) and dopamine transporter imaging using 123I-2ß-carbomethoxy-3ß-(4-iodophenyl)-N-(3-fluoropropyl)-nortropane (123I-FP-CIT) single-photon emission computerized tomography (SPECT) can evaluate Parkinsonism. Nigral hyperintensity from nigrosome-1 and striatal dopamine transporter uptake are reduced in Parkinsonism; however, quantification is only possible with SPECT. Here, we aimed to develop a deep-learning-based regressor model that can predict striatal 123I-FP-CIT uptake on nigrosome magnetic resonance imaging (MRI) as a biomarker for Parkinsonism. METHODS: Between February 2017 and December 2018, participants who underwent 3 T brain MRI including SWI and 123I-FP-CIT SPECT based on suspected Parkinsonism were included. Two neuroradiologists evaluated the nigral hyperintensity and annotated the centroids of nigrosome-1 structures. We used a convolutional neural network-based regression model to predict striatal specific binding ratios (SBRs) measured via SPECT using the cropped nigrosome images. The correlation between measured and predicted SBRs was evaluated. RESULTS: We included 367 participants (203 women (55.3%); age, 69.0 ± 9.2 [range, 39-88] years). Random data from 293 participants (80%) were used for training. In the test set (74 participants [20%]), the measured and predicted 123I-FP-CIT SBRs were significantly lower with the loss of nigral hyperintensity (2.31 ± 0.85 vs. 2.44 ± 0.90) than with intact nigral hyperintensity (4.16 ± 1.24 vs. 4.21 ± 1.35, P < 0.01). The sorted measured 123I-FP-CIT SBRs and the corresponding predicted values were significantly and positively correlated (ρc = 0.7443; 95% confidence interval, 0.6216-0.8314; P < 0.01). CONCLUSION: A deep learning-based regressor model effectively predicted striatal 123I-FP-CIT SBRs based on nigrosome MRI with high correlation using manually-measured values, enabling nigrosome MRI as a biomarker for nigrostriatal dopaminergic degeneration in Parkinsonism.

Relationship between protein intake and grip strength in qualitative and quantitative aspects among the elderly in Korea: results from the Korea National Health and Nutrition Examination Survey.

BACKGROUND: This study investigated the association between quantitative and qualitative protein intake and grip strength (GS) in the South Korean population to explore nutritional management for the prevention of sarcopenia. METHODS: This cross-sectional study was based on data from a nationally representative sample of the South Korean elderly population, consisting of 1,531 men and 1,983 women aged 65 years and older who participated in the Korean National Health and Nutrition Examination Survey from 2016 to 2019. Low GS was defined as GS < 28 kg in men and GS < 18 kg in women. Protein intake was assessed using 1-day 24-h recall, and we analyzed absolute protein intake, protein intake by food source, and protein intake compared to dietary reference intake with per body weight or absolute daily recommended value. RESULTS: The total and animal protein intake and protein intake from legumes, fish and shellfish were significantly lower in women with a low GS than in those with a normal GS. After adjusting for confounding factors, women who consumed more protein than the estimated average requirement (EAR, 40 g/day for women) were 0.528 times less likely to have low GS than women consuming less protein than the EAR (95% CI: 0.373-0.749), and consuming any amount of protein from legumes were 0.656 times less likely (95% CI: 0.500-0.860) to have low GS than women who did not consume any amount of legume protein. CONCLUSIONS: This study provides epidemiological evidence that adequate protein intake above EAR and protein intake from legumes should be guided for preventing low GS, especially in elderly women.

Diagnostic assessment of magnetic resonance imaging for patients with intralabyrinthine schwannoma: A systematic review.

OBJECTIVES: Recent advancements in high-resolution imaging have improved the diagnostic assessment of magnetic resonance imaging (MRI) for intralabyrinthine schwannoma (ILS). This systematic review aimed to evaluate the diagnostic performance of MRI for patients with ILS. METHODS: Ovid-MEDLINE and EMBASE databases were searched for related studies on the diagnostic performance of MRI for patients with ILS published up to February 10, 2020. The primary endpoint was the diagnostic performance of MRI for ILS. The quality of the enrolled studies was assessed using tailored questionnaires and the Quality Assessment of Diagnostic Accuracy Studies-2 criteria. RESULTS: Overall, 6 retrospective studies that included 122 patients with ILS from a parent population of 364 were included. The sample size, parent population and its composition, reference standard, detailed parameters of MRI, and even the diagnostic methods varied between the studies. The studies had moderate quality. The sensitivity of combination of T2WI and CE-T1WI was over 90%. Relative sensitivity of T2WI comparative to CE-T1WI ranged from 62% to 100%, and the specificity were 100%. CONCLUSIONS: MRI has acceptable diagnostic performance for ILS. There is a need for well-organized research to reduce the factors causing heterogeneity.

Imaging the Substantia Nigra in Parkinson Disease and Other Parkinsonian Syndromes.

Parkinson disease is characterized by dopaminergic cell loss in the substantia nigra of the midbrain. There are various imaging markers for Parkinson disease. Recent advances in MRI have enabled elucidation of the underlying pathophysiologic changes in the nigral structure. This has contributed to accurate and early diagnosis and has improved disease progression monitoring. This article aims to review recent developments in nigral imaging for Parkinson disease and other parkinsonian syndromes, including nigrosome imaging, neuromelanin imaging, quantitative iron mapping, and diffusion-tensor imaging. In particular, this article examines nigrosome imaging using 7-T MRI and 3-T susceptibility-weighted imaging. Finally, this article discusses volumetry and its clinical importance related to symptom manifestation. This review will improve understanding of recent advancements in nigral imaging of Parkinson disease. Published under a CC BY 4.0 license.

Diagnostic performance of neuromelanin-sensitive magnetic resonance imaging for patients with Parkinson's disease and factor analysis for its heterogeneity: a systematic review and meta-analysis.

OBJECTIVE: To determine the diagnostic performance of neuromelanin-sensitive magnetic resonance imaging discriminating between patients with Parkinson's disease and normal healthy controls and to identify factors causing heterogeneity influencing the diagnostic performance. METHODS: A systematic literature search in the Ovid-MEDLINE and EMBASE databases was performed for studies reporting the relevant topic before February 17, 2020. The pooled sensitivity and specificity values with their 95% confidence intervals were calculated using bivariate random-effects modeling. Subgroup and meta-regression analyses were also performed to determine factors influencing heterogeneity. RESULTS: Twelve articles including 403 patients with Parkinson's disease and 298 control participants were included in this systematic review and meta-analysis. Neuromelanin-sensitive magnetic resonance imaging showed a pooled sensitivity of 89% (95% confidence interval, 86-92%) and a pooled specificity of 83% (95% confidence interval, 76-88%). In the subgroup and meta-regression analysis, a disease duration longer than 5 and 10 years, comparisons using measured volumes instead of signal intensities, a slice thickness in terms of magnetic resonance imaging parameters of more than 2 mm, and semi-/automated segmentation methods instead of manual segmentation improved the diagnostic performance. CONCLUSION: Neuromelanin-sensitive magnetic resonance imaging had a favorable diagnostic performance in discriminating patients with Parkinson's disease from healthy controls. To improve diagnostic accuracy, further investigations directly comparing these heterogeneity-affecting factors and optimizing these parameters are necessary. KEY POINTS: • Neuromelanin-sensitive MRI favorably discriminates patients with Parkinson's disease from healthy controls. • Disease duration, parameters used for comparison, magnetic resonance imaging slice thickness, and segmentation methods affected heterogeneity across the studies.

Prediction model for cervical lymph node metastasis in human papillomavirus-related oropharyngeal squamous cell carcinomas.

OBJECTIVES: To develop and validate a risk scoring system based on clinical and imaging findings to predict lymph node metastasis from HPV-related oropharyngeal squamous cell carcinomas. METHODS: This study population who had undergone neck dissections or lymph node biopsies in patients with HPV+ OPSCC was obtained from a historical cohort from two tertiary referral hospitals. The training set from one hospital included 455 lymph nodes from 82 patients, and the test set from the other hospital included 150 lymph nodes from 42 patients. The baseline clinical and imaging findings on pretreatment CT or MR were investigated and the reference standards were the histopathologic results. A risk scoring system was constructed based on logistic regression and validated both internally and externally. RESULTS: A 7-point risk scoring system was developed based on the following variables: central necrosis, infiltration of adjacent planes, lymph node level, and the maximal axial diameter of the lymph node. This risk scoring system showed good discriminative ability for metastasis in the training set (C-statistic 0.952; 95% CI, 0.931-0.972) and test set (C-statistic 0.968, 95% CI, 0.936-0.999) and good calibration ability in the training set (p = 0.723) and test set (p = 0.253). CONCLUSIONS: We developed and validated a reliable risk scoring system that predicts lymph node metastasis from HPV+ OPSCCs based on the clinical data and pretreatment imaging findings. We expect this risk scoring system to be a useful guide for better decision-making in practice. KEY POINTS: • It is important to diagnose lymph node metastasis from HPV+ OPSCC for treatment planning; however, there has been little research on that. • We developed and externally validated a new scoring system for stratifying the risk of lymph node metastasis from HPV+ OPSCC based on clinical and imaging data. • A predictive model combining both clinical and imaging data showed high diagnostic accuracy and efficiency for lymph node metastasis from HPV+ OPSCC.

Diagnostic performance of MRI of post-laminar optic nerve invasion detection in retinoblastoma: A systematic review and meta-analysis.

PURPOSE: Preoperative MRI detection of post-laminar optic nerve invasion (PLONI) offers guidance in assessing the probability of total tumor resection, an estimation of the extent of surgery, and screening of candidates for eye-preserving therapies or neoadjuvant chemotherapies in the patients with retinoblastoma (RB). The purpose of this systematic review and meta-analysis was to evaluate the diagnostic performance of MRI for detecting PLONI in patients with RB and to demonstrate the factors that may influence the diagnostic performance. METHODS: Ovid-MEDLINE and EMBASE databases were searched up to January 11, 2020, for studies identifying the diagnostic performance of MRI for detecting PLONI in patients with RB. The pooled sensitivity and specificity of all studies were calculated followed by meta-regression analysis. RESULTS: Twelve (1240 patients, 1255 enucleated globes) studies were included. The pooled sensitivity was 61%, and the pooled specificity was 88%. Higgins I2 statistic demonstrated moderate heterogeneity in the sensitivity (I2 = 72.23%) and specificity (I2 = 78.11%). Spearman correlation coefficient indicated the presence of a threshold effect. In the meta-regression, higher magnetic field strength (3 T than 1.5 T), performing fat suppression, and thinner slice thickness (< 3 mm) were factors causing heterogeneity and enhancing diagnostic power across the included studies. CONCLUSIONS: MR imaging was demonstrated to have acceptable diagnostic performance in detecting PLONI in patients with RB. The variation in the magnetic field strength and protocols was the main factor behind the heterogeneity across the included studies. Therefore, there is room for developing and optimizing the MR protocols for patients with RB.

Estrogen receptor α as a predictive biomarker for survival in human papillomavirus-positive oropharyngeal squamous cell carcinoma.

BACKGROUND: Although oropharyngeal squamous cell carcinoma (OPSCC) with human papillomavirus (HPV) infection has a good prognosis, the accurate prediction of survival and risk of treatment failure is essential to design deintensification regimens. Here, we investigated estrogen receptor α (ERα) as a prognostic biomarker with therapeutic implications in OPSCC alongside factors associated with HPV infection. METHODS: We performed immunohistochemistry for ERα and p53 using formalin-fixed, paraffin-embedded tissues and assessed the HPV status using p16 immunohistochemistry and HPV DNA testing in 113 consecutive patients with OPSCC treated with surgical resection or radiotherapy/chemoradiotherapy. RESULTS: ERα expression and p53 alteration was observed in 35.4% and 21.2% OPSCCs; 45.6% and 1.3% p16+/HPV+ OPSCCs; and 11.5% and 76.9% p16- OPSCCs, respectively. These data suggest that OPSCC pathogenesis varies with HPV status. Furthermore, ERα expression was associated with improved overall survival (OS) in both HPV+ (p16+/HPV+ OPSCC) and p16+ (p16+ OPSCC irrespective of HPV status) models (p = 0.005 and p = 0.006, respectively) and with improved OS adjusted for stage (p = 0.037, hazard ratio: 0.109, 95% confidence interval 0.013-0.871) in the p16+ model. CONCLUSIONS: ERα is a potential predictive biomarker for improved survival in both HPV+ and p16+ OPSCC models.

Clinical Perspectives of Parkinson's Disease for Ophthalmologists, Otorhinolaryngologists, Cardiologists, Dentists, Gastroenterologists, Urologists, Physiatrists, and Psychiatrists.

Parkinson's disease (PD) is a multisystemic disorder characterized by various non-motor symptoms (NMS) in addition to motor dysfunction. NMS include sleep, ocular, olfactory, throat, cardiovascular, gastrointestinal, genitourinary, or musculoskeletal disorders. A range of NMS, particularly hyposmia, sleep disturbances, constipation, and depression, can even appear prior to the motor symptoms of PD. Because NMS can affect multiple organs and result in major disabilities, the recognition and multidisciplinary and collaborative management of NMS by physicians is essential for patients with PD. Therefore, the aim of this review article is to provide an overview of the organs that are affected by NMS in PD together with a brief review of pathophysiology and treatment options.

Association between the Frequency of Dining Out and the Risk of Obesity, Diabetes Mellitus, and Dyslipidemia among Korean Adults.

This study aimed to clarify the association between the frequency of dining out and the risk of obesity, diabetes mellitus, and dyslipidemia among Korean adults. This cross-sectional study surveyed 640 participants aged 20-69 years in Korea. Daily intake of energy, fat, protein, and cholesterol significantly increased as the frequency of dining out increased (P < .001). Energy derived from carbohydrates significantly decreased with the frequency of dining out, while that derived from fat and protein increased (P < .001). Among participants who rarely dined out, the fully adjusted odds ratios (ORs) for hyperglycemia were significantly lower at 0.35 (95% CI, 0.16-0.76). Decreased risk of being hyperglycemia among participants who rarely dined out suggests that the frequency of dining out can be related to diabetes risk.

Loss of Substantia Nigra Hyperintensity at 3.0-T MR Imaging in Idiopathic REM Sleep Behavior Disorder: Comparison with 123I-FP-CIT SPECT.

Purpose To examine whether the loss of nigral hyperintensity (NH) on 3.0-T susceptibility-weighted (SW) magnetic resonance (MR) images can help identify high synucleinopathy risk in patients with idiopathic rapid eye movement sleep behavior disorder (iRBD). Materials and Methods Between March 2014 and April 2015, 18 consecutively recruited patients with iRBD were evaluated with 3.0-T SW imaging and iodine 123-2ß-carbomethoxy-3ß-(4-iodophenyl)-N-(3-fluoropropyl)-nortropane (123I-FP-CIT) single photon emission computed tomography and compared with 18 healthy subjects and 18 patients with Parkinson disease (PD). Two readers blinded to clinical diagnosis independently assessed the images. 123I-FP-CIT uptake ratios were compared by using the Kruskal-Wallis test, and intra- and interobserver agreements were assessed with the Cohen κ. The synucleinopathy conversion according to NH status was evaluated in patients with iRBD after follow-up. Results NH was intact in seven patients with iRBD and lost in 11. The 123I-FP-CIT uptake ratios were comparable between those with intact NH (mean, 3.22 ± 0.47) and healthy subjects (mean, 3.37 ± 0.47) (P = .495). The 123I-FP-CIT uptake ratios in the 11 patients with iRBD and NH loss (mean, 2.48 ± 0.44) were significantly lower than those in healthy subjects (mean, 3.37 ± 0.47; P < .001) but higher than those in patients with PD (mean, 1.80 ± 0.33; P < .001). The intra- and interobserver agreements were excellent (κ > 0.9). Five patients with iRBD and NH loss developed symptoms of parkinsonism or dementia 18 months after neuroimaging. Conclusion NH loss at 3.0-T SW imaging may be a promising marker for short-term synucleinopathy risk in iRBD. © RSNA, 2017 Online supplemental material is available for this article.

Psychiatric Manifestation in Patients with Parkinson's Disease.

Parkinson's disease (PD) is the second most common neurodegenerative disorder. Although its major manifestation is motor symptoms, resulting from the loss of dopaminergic neurons in the substantia nigra, psychiatric symptoms, such as depression, anxiety, hallucination, delusion, apathy and anhedonia, impulsive and compulsive behaviors, and cognitive dysfunction, may also manifest in most patients with PD. Given that the quality of life - and the need for institutionalization - is so highly dependent on the psychiatric well-being of patients with PD, psychiatric symptoms are of high clinical significance. We reviewed the prevalence, risk factors, pathophysiology, and treatment of psychiatric symptoms to get a better understanding of PD for improved management.

The Prevalence of Cerebral Microbleeds in Non-Demented Parkinson's Disease Patients.

BACKGROUND: Cerebral microbleeds (CMBs) are associated with cerebrovascular risk factors and cognitive dysfunction among patients with Parkinson's disease (PD). However, whether CMBs themselves are associated with PD is to be elucidated. METHODS: We analyzed the presence of CMBs using 3-Tesla brain magnetic resonance imaging in non-demented patients with PD and in age-, sex-, and hypertension-matched control subjects. PD patients were classified according to their motor subtypes: tremor-dominant, intermediate, and postural instability-gait disturbance (PIGD). Other cerebrovascular risk factors and small vessel disease (SVD) burdens were also evaluated. RESULTS: Two-hundred and five patients with PD and 205 control subjects were included. The prevalence of CMBs was higher in PD patients than in controls (16.1% vs. 8.8%; odds ratio [OR], 2.126; P = 0.019); CMBs in the lobar area showed a significant difference between PD patients and controls (11.7% vs. 5.9%; OR, 2.234; P = 0.032). According to the motor subtype, CMBs in those with PIGD type showed significant difference from controls with respect to the overall brain area (21.1% vs. 8.9%; OR, 2.759; P = 0.010) and lobar area (14.6% vs. 4.9%; OR, 3.336; P = 0.016). Among PD patients, those with CMBs had higher age and more evidence of SVDs than those without CMBs. CONCLUSION: We found that CMBs are more frequent in PD patients than in controls, especially in those with the PIGD subtype and CMBs on the lobar area. Further study investigating the pathogenetic significance of CMBs is required.

Is multidetector computed tomography comparable to magnetic resonance imaging for assessment of lumbar foraminal stenosis?

Background Both multidetector computed tomography (MDCT) and magnetic resonance imaging (MRI) are used for assessment of lumbar foraminal stenosis (LFS). Therefore, it is relevant to assess agreement between these imaging modalities. Purpose To determine intermodality, inter-, and intra-observer agreement for assessment of LFS on MDCT and MRI. Material and Methods A total of 120 foramina in 20 patients who visited our institution in January and February 2014 were evaluated by six radiologists with different levels of experience. Radiologists evaluated presence and severity of LFS on sagittal CT and MR images according to a previously published LFS grading system. Intermodality agreement was analyzed by using weighted kappa statistics, while inter- and intra-observer agreement were analyzed by using intraclass correlation coefficients (ICCs) and kappa statistics. Results Overall intermodality agreement was moderate to good (kappa, 0.478-0.765). In particular, two professors and one fellow tended to overestimate the degree of LFS on CT compared with MRI. For inter-observer agreement of all six observers, ICCs indicated excellent agreement for both CT (0.774) and MRI (0.771), while Fleiss' kappa values showed moderate agreement for CT (0.482) and MRI (0.575). There was better agreement between professors and fellows compared with residents. For intra-observer agreement, ICCs indicated excellent agreement, while kappa values showed good to excellent agreement for both CT and MRI. Conclusion MDCT was comparable to MRI for diagnosis and assessment of LFS, especially for experienced observers. However, there was a tendency to overestimate the degree of LFS on MDCT compared with MRI.

Cervical compressive myelopathy: flow analysis of cerebrospinal fluid using phase-contrast magnetic resonance imaging.

PURPOSE: To evaluate cerebrospinal fluid (CSF) flow in cervical compressive myelopathy (CCM), by both quantitative and qualitative analyses, using 3T cine phase-contrast magnetic resonance imaging (cine MRI). METHODS: From September, 2014 to June, 2015, we enrolled 45 subjects (18 women and 27 men, mean age, 61.7 ± 13.4 years) to undergo cervical cine MRI. The subjects were divided into three groups: no stenosis and cervical stenosis with and without intramedullary T2 hyperintensity. We measured maximal CSF velocity, and 12 CSF velocity waveforms were plotted per subject. Two readers independently assessed the CSF waveform shape (0 absent; 1 serrated; 2 bi-directional with small amplitude; and 3 normal bi-directional waveform) and the CSF motion pattern (0 absent; 1 interrupted; and 2 intact). The numbers of 12 waveform shapes were summed to yield a CSF waveform score. Linear mixed model and ROC curve analyses were used for statistical analyses. RESULTS: Maximal CSF velocity was significantly lower in CCM (marginal mean, 2.72 cm/s) than in stenosis without intramedullary T2 hyperintensity (3.27 cm/s, p = 0.027) and no stenosis (3.80 cm/s, p < 0.001). Bi-phasic CSF motion was lost in cervical stenosis. CSF waveform scores of 17 (area under curve (AUC), 0.797; p = 0.003) and 16.5 (AUC, 0.790; p = 0.004) could predict Japanese Orthopedic Association (JOA) score corresponding to CCM. CONCLUSIONS: Maximal CSF velocity and CSF waveform score on cine MRI decreased in CCM and was correlated with the JOA score. Thus, both quantitative and qualitative analyses using cine MRI could effectively demonstrate CSF flow alterations in CCM.

Loss of Nigral Hyperintensity on 3 Tesla MRI of Parkinsonism: Comparison With (123) I-FP-CIT SPECT.

BACKGROUND: The aim of this study was to investigate whether 3 Tesla susceptibility-weighted imaging can detect the alteration of substantia nigra hyperintensity in Parkinson's disease (PD), multiple system atrophy (MSA), and progressive supranuclear palsy (PSP) and to assess the concordance between the loss of nigral hyperintensity on 3 Tesla susceptibility-weighted imaging and the nigrostriatal dopaminergic degeneration indicated by (123) I-2ß-carbomethoxy-3ß-(4-iodophenyl)-N-(3-fluoropropyl)-nortropane single photon emission computerized tomography. METHODS: Consecutive subjects with suspected parkinsonism were included, and clinical diagnosis was solidified during clinical follow-up. Two blinded neuroradiologists interpreted the nigral hyperintensity on susceptibility-weighted imaging. The performance of susceptibility-weighted imaging for detection of nigral hyperintensity loss was estimated on the basis of the clinical diagnosis and compared with single photon emission computerized tomography results. RESULTS: The study included 210 subjects (126 PD, 11 MSA, 11 PSP patients, 26 healthy controls, 36 disease controls). The presence or absence of nigral hyperintensity was accurately visualized in 112 PD, 7 MSA, and 11 PSP patients and 53 controls. We identified 16 false-negative cases and 11 false-positive cases. The sensitivity and specificity of susceptibility-weighted imaging were 88.8% and 83.6%, respectively. The concordance rate between susceptibility-weighted imaging and single photon emission computerized tomography was 86.2%. CONCLUSIONS: The loss of nigral hyperintensity on susceptibility-weighted imaging suggested nigrostriatal dopaminergic degeneration in a large portion of patients with parkinsonism, which was indicated by (123) I-2ß-carbomethoxy-3ß-(4-iodophenyl)-N-(3-fluoropropyl)-nortropane single photon emission computerized tomography. In consideration of false-negative and -positive cases, well-designed imaging protocols should be introduced to improve the performance of nigral hyperintensity imaging. © 2016 International Parkinson and Movement Disorder Society.

Early Stage of Hyperintense Acute Reperfusion Marker on Contrast-Enhanced FLAIR Images in Patients With Acute Stroke.

OBJECTIVE: Hyperintense acute reperfusion marker (HARM) is defined as delayed CSF enhancement on FLAIR images in patients with acute stroke and was observed in follow-up FLAIR images after initial MRI with contrast material administration. We hypothesized that different imaging findings of HARM could be present depending on the timing of FLAIR imaging after contrast material administration. SUBJECTS AND METHODS: Of 218 consecutive patients with acute stroke or transient ischemic attack over 3 months, 12 with linear contrast enhancement on the cortical surface in initial FLAIR images underwent serial FLAIR imaging. Initial FLAIR images were obtained 5 minutes after contrast material administration, and follow-up unenhanced FLAIR images were obtained 2.5-29 hours (mean, 13.2 hours) after initial FLAIR imaging. The enhancement patterns between initial and follow-up FLAIR images were compared. RESULTS: In all 12 patients, initial contrast-enhanced FLAIR images showed focal or multifocal linear contrast enhancement along the cortical surface near acute infarctions. On follow-up unenhanced FLAIR images, initial cortical enhancement spread diffusely and filled the subarachnoid space. CONCLUSION: HARM in acute stroke can be detected earlier than previously reported on initial contrast-enhanced FLAIR images. Different imaging findings of HARM depend on the timing of FLAIR imaging after contrast material administration.