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Introduction: The primary objective was to investigate the value of the fluid attenuated inversion recovery (FLAIR) signal intensity ratio (SIR) in identifying stroke within 4.5 h. The secondary objective was to ascertain whether large vessel occlusion (LVO) mediated the relationship between the SIR and stroke within 4.5 h. Methods: We analyzed 633 acute stroke patients within 24 h of clear symptom onset. The SIR and DWI-FLAIR mismatch were evaluated. First, we determined whether demographic variables, vascular risk factors and LVO were related to stroke within 4.5 h with multivariate logistic regression analyses and stratified regression analysis. Next, we used mediation analysis to determine whether LVO explained the association between SIR and stroke within 4.5 h. Finally, we used receiver operating characteristic (ROC) analysis to assess the value of SIR, independent variable, and multiparameter models in identifying stroke within 4.5 h and compared with DWI-FLAIR mismatch. Results: Hyperlipemia, LVO and SIR were associated with stroke within 4.5 h. Mediation analysis revealed that LVO partially mediated the relationship between SIR and stroke within 4.5 h (p < 0.001). The multiparameter model (hyperlipemia, LVO and SIR) showed significantly improved performance (AUC 0.869) in identifying stroke within 4.5 h over DWI-FLAIR mismatch (0.684), hyperlipemia (0.632), LVO (0.667) and SIR (0.773) models. Conclusion: SIR is associated with stroke within 4.5 h, and LVO partially mediates this relationship. A multiparameter model combining hyperlipemia, LVO and SIR can more accurately identify stroke within 4.5 h than individual parameter models. [ABSTRACT FROM AUTHOR]

PURPOSE: Tacrolimus is a commonly used immunosuppressant medication after lung transplantation. In rare cases, tacrolimus causes a medication-induced optic neuropathy (TON) that can lead to significant vision loss. OBSERVATIONS: In this series, we describe three cases of TON, 1-10 years after medication use. Two patients were young (22yr and 33yr) females with cystic fibrosis. The last case was a 65yr male with idiopathic pulmonary fibrosis. In 2/3 cases tacrolimus serum levels were normal. Visual acuity ranged from 20/20 to 20/300, and vision loss occurred acutely to sub-acutely, over a span of 2-3 months. CONCLUSIONS AND IMPORTANCE: As presented here, TON can be highly variable. MRI findings are often non-specific, from normal brain findings to extensive white matter changes. There remains an unclear association with graft-versus-host disease and reduced kidney function. Visual findings are often subtle, including color vision aberration and peripheral visual field deficits, both of which usually require an ophthalmologic evaluation. When diagnosed in a timely fashion, TON is at least partially reversible in up to half of all cases. While rare, the cases described here support post-lung transplant ophthalmologic evaluation in those taking high-risk medications.

OBJECTIVE Accurate presurgical localization of microadenomas in Cushings disease (CD) leads to improved remission rates and decreased adverse events. Volumetric gradient recalled echo (3D-GRE) MRI detects pituitary microadenomas in CD in up to 50%-80% cases as a focus of hypointensity due to delayed contrast wash-in. The authors have previously reported that postcontrast FLAIR imaging may be useful in detecting otherwise MRI-negative pituitary microadenomas as foci of hyperintensity. This reflects theoretically complementary imaging of microadenomas due to delayed contrast washout. The authors report on the diagnostic accuracy and clinical utility of FLAIR imaging in the detection of microadenomas in patients with CD. METHODS The authors prospectively analyzed imaging findings in 23 patients (24 tumors) with biochemically proven CD who underwent transsphenoidal surgery for CD. Preoperatively, the patients underwent pituitary MRI with postcontrast FLAIR and postcontrast 3D-GRE sequences. RESULTS Postcontrast FLAIR hyperintensity was detected in macroadenomas, and in 3D-GRE-positive or -negative microadenomas. Overall, 3D-GRE was superior in detecting surgically and histopathologically confirmed, location-concordant microadenomas. Of 24 pituitary adenomas, 18 (75%; sensitivity 82%, positive predictive value 95%) were found on 3D-GRE, and 13 (50% [1 was false positive]; sensitivity 55%, positive predictive value 92%) were correctly identified on FLAIR. The stand-alone specificity of 3D-GRE and FLAIR was similar (50%). These results confirm the superiority of 3D-GRE as a stand-alone imaging modality. The authors then tested the utility of FLAIR as a complementary tool to 3D-GRE imaging. All 5 patients with negative 3D-GRE MRI displayed a distinct focus of FLAIR enhancement. Four of those 5 cases (80%) had location-concordant positive histopathological results and achieved postsurgical biochemical remission. The remaining patient was not cured, because resection did not include the region of FLAIR hyperintensity. CONCLUSIONS This study suggests that delayed microadenoma contrast washout may be detected as FLAIR hyperintensity in otherwise MRI-negative CD cases. The authors propose adding postcontrast FLAIR sequences to complement 3D-GRE for surgical planning in patients with CD. Clinical trial registration no.: NIH protocol 03-N-0164, NCT00060541 (clinicaltrials.gov).

Purpose: To determine the magnetic resonance imaging (MRI) features which could pre-operatively differentiate chordoid meningioma (CM) from other histopathological subtypes of meningioma. Methods: Retrospective analysis of pre-operative MRI of cases with histopathologically confirmed diagnosis of meningioma during the last 5 years at our institute was done. T1W, T2W, FLAIR sequences, and post-contrast enhancement were evaluated on a qualitative scale. Normalized ADC ratios (nADCR) and normalized fractional anisotropy ratios (nFAR) were derived. The intratumoral susceptibility score (ITSS), presence of sunburst pattern of vasculature, bone changes, tumour-parenchyma interface, and oedema-to-tumour ratio were also determined. Results: A total of 81 lesions were analyzed out of which 15 were CM. CM showed a higher relative contrast enhancement as compared to all other subtypes except for angiomatous and microcystic meningioma. Relative signal intensity on FLAIR could differentiate CM from transitional meningioma. nFAR was found to be significantly higher in fibroblastic meningioma and significantly lower in microcystic meningiomas as compared to CM. Anaplastic meningiomas were remarkable for bone changes and an ill-defined tumour-brain interface in significantly higher proportion of cases as compared to CM. nADCR > 1.5 was found to be an independent predictor of CM with a sensitivity of 84.6%, specificity of 89.8%, positive predictive value of 64.7%, and negative predictive value of 96.4%. Conclusion: Routine pre-operative MRI may be able to differentiate CM from other meningioma subtypes and a cut-off value of greater than 1.5 for nADCR could be predictive of > 50% chordoid histology of meningioma with a high sensitivity, specificity, and negative predictive value. [ABSTRACT FROM AUTHOR]

Introduction: The primary objective was to investigate the value of the fluid attenuated inversion recovery (FLAIR) signal intensity ratio (SIR) in identifying stroke within 4.5 h. The secondary objective was to ascertain whether large vessel occlusion (LVO) mediated the relationship between the SIR and stroke within 4.5 h., Methods: We analyzed 633 acute stroke patients within 24 h of clear symptom onset. The SIR and DWI-FLAIR mismatch were evaluated. First, we determined whether demographic variables, vascular risk factors and LVO were related to stroke within 4.5 h with multivariate logistic regression analyses and stratified regression analysis. Next, we used mediation analysis to determine whether LVO explained the association between SIR and stroke within 4.5 h. Finally, we used receiver operating characteristic (ROC) analysis to assess the value of SIR, independent variable, and multiparameter models in identifying stroke within 4.5 h and compared with DWI-FLAIR mismatch., Results: Hyperlipemia, LVO and SIR were associated with stroke within 4.5 h. Mediation analysis revealed that LVO partially mediated the relationship between SIR and stroke within 4.5 h ( p  < 0.001). The multiparameter model (hyperlipemia, LVO and SIR) showed significantly improved performance (AUC 0.869) in identifying stroke within 4.5 h over DWI-FLAIR mismatch (0.684), hyperlipemia (0.632), LVO (0.667) and SIR (0.773) models., Conclusion: SIR is associated with stroke within 4.5 h, and LVO partially mediates this relationship. A multiparameter model combining hyperlipemia, LVO and SIR can more accurately identify stroke within 4.5 h than individual parameter models., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Wang, Mao, Jiang, Peng, Chen, Zhang, Wang and Yin.)

BackgroundThe presence of fluid attenuated inversion recovery (FLAIR)-hyperintense lesions in anti-myelin oligodendrocyte glycoprotein (MOG) antibody-associated cerebral cortical encephalitis with seizures (FLAMCES) was recently reported. However, the clinical characteristics and outcome of this rare clinico-radiographic syndrome remain unclear.MethodsThe present study reported two new cases. In addition, cases in the literature were systematically reviewed to investigate the clinical symptoms, magnetic resonance imaging (MRI) abnormalities, treatments and prognosis for this rare clinico-radiographic syndrome.ResultsA total of 21 cases were identified during a literature review, with a mean patient age at onset of 26.8 years. The primary clinicopathological characteristics included seizures (100%), headache (71.4%), fever (52.3%) and other cortical symptoms associated with the encephalitis location (61.9%). The common seizure types were focal to bilateral tonic-clonic seizures (28.6%) and unknown-onset tonic-clonic seizures (38.1%). The cortical abnormalities on MRI FLAIR imaging were commonly located in the frontal (58.8%), parietal (70.6%) and temporal (64.7%) lobes. In addition, pleocytosis in the cerebrospinal fluid was reported in the majority of the patients (95.2%). All patients received a treatment regimen of corticosteroids and 9 patients received anti-epileptic drugs. Clinical improvement was achieved in all patients; however, one-third of the patients reported relapse following recovery from cortical encephalitis.ConclusionsFLAMCES is a rare phenotype of MOG-associated disease. Thus, the wider recognition of this rare syndrome may enable timely diagnosis and the development of suitable treatment regimens.

Background: The presence of fluid attenuated inversion recovery (FLAIR)-hyperintense lesions in anti-myelin oligodendrocyte glycoprotein (MOG) antibody-associated cerebral cortical encephalitis with seizures (FLAMCES) was recently reported. However, the clinical characteristics and outcome of this rare clinico-radiographic syndrome remain unclear. Methods: The present study reported two new cases. In addition, cases in the literature were systematically reviewed to investigate the clinical symptoms, magnetic resonance imaging (MRI) abnormalities, treatments and prognosis for this rare clinico-radiographic syndrome. Results: A total of 21 cases were identified during a literature review, with a mean patient age at onset of 26.8 years. The primary clinicopathological characteristics included seizures (100%), headache (71.4%), fever (52.3%) and other cortical symptoms associated with the encephalitis location (61.9%). The common seizure types were focal to bilateral tonic-clonic seizures (28.6%) and unknown-onset tonic-clonic seizures (38.1%). The cortical abnormalities on MRI FLAIR imaging were commonly located in the frontal (58.8%), parietal (70.6%) and temporal (64.7%) lobes. In addition, pleocytosis in the cerebrospinal fluid was reported in the majority of the patients (95.2%). All patients received a treatment regimen of corticosteroids and 9 patients received anti-epileptic drugs. Clinical improvement was achieved in all patients; however, one-third of the patients reported relapse following recovery from cortical encephalitis. Conclusions: FLAMCES is a rare phenotype of MOG-associated disease. Thus, the wider recognition of this rare syndrome may enable timely diagnosis and the development of suitable treatment regimens. [ABSTRACT FROM AUTHOR]

Recent contributions to the body of knowledge on traumatic brain injury (TBI) favor the view that multimodal neuroimaging using structural and functional magnetic resonance imaging (MRI and fMRI, respectively) as well as diffusion tensor imaging (DTI) has excellent potential to identify novel biomarkers and predictors of TBI outcome. This is particularly the case when such methods are appropriately combined with volumetric/morphometric analysis of brain structures and with the exploration of TBI-related changes in brain network properties at the level of the connectome. In this context, our present review summarizes recent developments on the roles of these two techniques in the search for novel structural neuroimaging biomarkers that have TBI outcome prognostication value. The themes being explored cover notable trends in this area of research, including (1) the role of advanced MRI processing methods in the analysis of structural pathology, (2) the use of brain connectomics and network analysis to identify outcome biomarkers, and (3) the application of multivariate statistics to predict outcome using neuroimaging metrics. The goal of the review is to draw the community's attention to these recent advances on TBI outcome prediction methods and to encourage the development of new methodologies whereby structural neuroimaging can be used to identify biomarkers of TBI outcome.

目的 利用半自动化分析软件对脑白质疏松患者不同区域白质损伤进行定量，并对其与认知功能评 分进行偏相关分析。 方法 2011年1月-2017年1月在北京天坛医院进行健康体检的50～85岁社区“健康”人群63例，对 其进行认知功能评价[简易精神状态量表（mi ni -mental state examination，MMSE）、蒙特利尔认知量表 （Montreal cognitive assessment，MoCA）]及影像学数据采集，基于液体衰减反转恢复序列定量计算全脑、 侧脑室旁及深部皮层下脑白质受损体积，将认知功能评分与以上白质受损体积进行偏相关分析，探 索白质受损在认知障碍发生发展过程中所起的作用。 结果 控制年龄、性别、文化程度后，全脑白质体积与MMSE评分、MoCA评分有偏相关性（R’=-0.428， P =0.001）（R’=-0.539，P＜0.001），尤其是侧脑室旁白质体积（R’=-0.427，P =0.001）（R’=-0.559，P ＜0.001），与深部皮层下白质也存在偏相关性（R’=-0.365，P =0.004）（R’=-0.447，P＜0.001）。 结论 全脑、侧脑室旁、深部皮层下脑白质损伤体积增大，认知功能评分随之下降；MMSE评分、 MoCA评分与侧脑室旁白质损伤之间的相关性较深部皮层下白质损伤更大。 Abstract: Objective To analyze white matter hyperintensity (WMH) in different brain regions in patients with cerebral leukoaraiosis using semi-automatic quantitative analysis software, and analyze the partial correlation of WMH and cognitive impairment. Methods A total of 63 ‘healthy’ community subjects (50-85 years) who had a physical examination in Beijing Tiantan hospital from January 2011 to January 2017 were included in this study. The cognitive function of all subjects were assessed using mini-mental state examination (MMSE) and Montreal cognitive assessment (MoCA). We quantitatively analyzed the WMH in the whole brain, periventricular and deep cortex on fluid attenuated inversion recovery (FLAIR) sequence, which represented white matter lesion, and made a partial correlation analysis of the volume of white matter lesion and cognitive function score, to investigate the role of white matter lesion in the development of cognitive impairment. Results After adjusting for age, gender and education level, the volume of whole brain white matter lesion still had a partial correlation with MMSE and MoCA scores (R’=-0.428, P =0.001; R’=-0.539, P

To investigate effect of MR field strength on texture features of cerebral T2 fluid attenuated inversion recovery (T2-FLAIR) images. We acquired cerebral 3D T2-FLAIR images of thirty patients who were diagnosed with ischemic white matter lesion (WML) with MR-1.5T and MR-3.0T scanners. Histogram texture features which included mean signal intensity (Mean), Skewness and Kurtosis, and gray level co-occurrence matrix (GLCM) texture features which included angular second moment (ASM), Contrast, Correlation, Inverse difference moment (IDM) and Entropy, of regions of interest located in the area of WML and normal white matter (NWM) were measured by ImageJ software. The texture parameters acquired with MR-1.5T scanning were compared with MR-3.0T scanning. The Mean of both WML and NWM obtained with MR-1.5T scanning was significantly lower than that acquired with MR-3.0T (p <0.001), while Skewness and Kurtosis between MR-1.5T and MR-3.0T scanning showed no significant difference (p >0.05). ASM, Correlation and IDM of both WML and NWM acquired with MR-1.5T revealed significantly lower values than those with MR-3.0T (p <0.001), while Contrast and Entropy acquired with MR-1.ST showed significantly higher values than those with MR-3.0T (p <0.001). MR field strength showed no significant effect on histogram textures, while had significant effect on GLCM texture features of cerebral T2-FLAIR images, which indicated that it should be cautious to explain the texture results acquired based on the different MR field strength. [ABSTRACT FROM AUTHOR]

Background: Previous studies have tried to relate magnetic resonance (MR) characteristics of meningiomas with its intraoperative features and histopathology with varying results. This is a prospective study to assess the independent predictive value of conventional MR signals [T1, T2, and fluid attenuated inversion recovery (FLAIR)] in relation to consistency, vascularity, operative plane, Simpson excision, and histopathology of intracranial meningiomas in a multivariate model.Materials and Methods: Seventy patients underwent T1, T2, FLAIR, postcontrast sequences followed by excision of their meningiomas. Tumor signal intensity in various sequences was studied in relation to the above-mentioned variables. Multivariate analysis to find their independent association was performed.Results: T1 images showed no correlation with any of the variables. FLAIR hypointensity and inhomogeneous enhancement had significant association with tumor hardness. FLAIR hypointense tumors were associated with low vascularity. FLAIR hypointensity, skull base location, and recurrence were significantly related to the subpial or mixed operative plane. The meningioma-brain interface on T2 sequence was significantly related to the operative plane. Only skull base location had significant impact on the extent of excision. T2 and FLAIR hypointensity had significant association with fibroblastic or psammomatous meningiomas. On multivariate analysis, FLAIR hypointensity and skull base location had a significant independent relationship with suboptimal operative plane, while skull base location had association with the extent of excision. Among MRI sequences, FLAIR hypointensity showed high specificity (94%) in predicting the suboptimal operative plane.Conclusions: FLAIR hypointensity of meningiomas appears to have a significant independent association with the suboptimal operative plane with high specificity. [ABSTRACT FROM AUTHOR]

Background Cerebral Amyloid Angiopathy (CAA) is an age-related disorder characterised by deposition of beta-amyloid protein in the walls of small and medium cortical vessels leading to increased risk of intracranial bleeding. CAA-Related Inflammation (CAA-ri) is an under recognised subtype of CAA potentially responsive to immunosuppression and traditionally diagnosed by invasive brain biopsy. CAA-ri is associated with rapid cognitive decline but shows reversibility for some when treated with immunosuppression. We present the case of an 82 year old lady who presented with first seizure, a history of notable cognitive change and neuroimaging consistent with probable CAA-ri. Methods Validated clinicoradiological diagnostic criteria for CAA-ri were applied to MRI T2 FLAIR and SWI sequences. CSF, APOE genotyping, EEG and cognitive testing were performed. Interdisciplinary perspectives were sought from Neurology, Neurosurgery and Infectious Diseases colleagues. Consensus opinion opposed brain biopsy on strength of imaging evidence and pulsed intravenous steroid treatment was initiated. BP, anti-convulsant and bone protection were optimised and anti-thrombotics avoided. Repeat imaging and cognitive testing were repeated after four months. Results MRI T2-FLAIR revealed an asymmetric multifocal distribution of cortical and subcortical white matter hyperintensities (WMH) with leptomeningeal enhancement while SWI showed extensive multifocal microhaemorrhages with confluent haemorrhage in the right frontal and temporal regions. EEG demonstrated right frontal theta slowing and absence of epileptiform activity. CSF analysis reported raised protein at 53mg/dl. Normal WCC. Formal cognitive testing with ACEIII revealed a score of 79/100. EPOA was advised. Conclusion Clinicoradiological diagnosis of CAA-ri permits early initiation of immunosuppressive therapy and avoids invasive brain biopsy. In the absence of clinical suspicion and blood sensitive imaging sequences CAA-ri may be misdiagnosed as Acute Ischaemic Stroke or TIA where the addition of anti-thrombotic therapy could cause harm while early medical management offers potential reversibility. [ABSTRACT FROM AUTHOR]

Background Although chronic subdural hematoma (CSDH) has a good prognosis after classical minimally-invasive drainage surgery, severe complications still occur at a substantial rate. Cerebral hyperperfusion syndrome (CHS), which is a common severe complication after carotid endarterectomy or carotid artery stenting for cervical carotid artery stenosis, is rare after drainage surgery for a CSDH. Case Description We describe the case of an 82-year-old woman who presented with ipsilesional symptoms including contralateral hemiparesis and dysarthria, progressively worsening consciousness, and status epilepticus after a burr hole drainage surgery for CSDH. Magnetic resonance fluid-attenuated inversion recovery imaging showed diffuse subcortical low intensity in the ipsilesional hemisphere almost simultaneously with the appearance of the symptoms. Arterial spin labeling magnetic resonance perfusion imaging showed the abnormal increase of cerebral blood flow in the hemisphere. Continuous propofol administration and blood pressure management improved the symptoms. Conclusions CHS can cause severe postoperative complications after drainage surgery for CSDH. Subcortical low-intensity fluid-attenuated inversion recovery imaging is a useful investigation for early detection of CHS in CSDH, and arterial spin labeling imaging is an effective minimally-invasive modality for confirming the diagnosis. [ABSTRACT FROM AUTHOR]

Background: Increased white matter hyperintensities (WMHs) is one of the most consistent imaging findings amongst participants with bipolar disorder (BD). This study investigated WMHs in a young population at high genetic risk for bipolar disorder (HR).Methods: MRI scans were conducted at baseline in HR individuals (n = 131), patients with BD (n = 47) and controls (CON) (n = 108). Most of the HR (n = 77) and CON (n = 74) group completed scans after two years. Scans were examined for the presence of WMHs.Results: There were significantly more periventricular WMHs in the BD compared to the CON group at baseline (p = .04). Although the prevalence of periventricular WMHs was intermediate in the HR group, there were no significant differences between the HR and CON or BD participants. Deep WMHs did not differ significantly between the groups. Over time, there was a significant increase in the prevalence of periventricular WMHs in both the HR and CON groups (p = .02).Limitations: The use of a visual rating scale to examine WMHs is subjective. As the gradings were collapsed into 'present' or 'absent', we could not ascertain whether the severity of hyperintensities worsened over time.Conclusions: Periventricular WMHs are more prevalent in young individuals with BD than controls. As these are not more prevalent in HR individuals, it is possible that these are either secondary to the development of bipolar disorder, its treatment, or resulting changes in lifestyle. In a novel finding, there were similar increases in the prevalence of WMHs in controls and HR youth over the 2-year period. [ABSTRACT FROM AUTHOR]

Double Inversion Recovery (DIR) is a robust sequence designed to suppress fat and water signals using two 180° inversion pulses to produce prominent gray matter contrast with high spatial resolution. It has proven to be more sensitive in delineating white matter signal abnormalities than conventional MR techniques. In our study, the highest image contrast with lesion load was observed using DIR over FLAIR and T2 weighted imaging. DIR is evidently valuable for the detection of demyelinating lesions observed in multiple sclerosis (MS), malignancies, epileptogenic foci, and cortical anomalies. Hence this pictorial review is intended to assess the diagnostic efficacy of DIR modality in clinical Neuro-imaging. [ABSTRACT FROM AUTHOR]

Background: When wounds are benign, diagnosis of deep brain stimulation (DBS) electrode infection and associated intraparenchymal infection can be challenging. Only a couple, such cases exist in literature. Since infections of the central nervous system can be life-threatening, prompt diagnosis is necessary to prevent neurological injury. Employed within the appropriate context, magnetic resonance imaging (MRI) of the brain, as well as laboratory data and clinical presentation, may help guide diagnosis. Case Descriptions: Case 1 - A 55-year-old male with bilateral DBS electrodes and generators (49 days from last procedure), who presented with confusion and fever. Pertinent positive laboratory was white blood cell 20.5K. MRI of the brain showed edema with enhancement along the right DBS electrode. Wound exploration revealed gross purulence in the subgaleal space. The entire system was removed; cultures from subgaleal space revealed Propionibacterium acnes; cultures from electrode were negative. The patient was sent home on antibiotics. Case 2 - A 68-year-old male with a right DBS electrode (11 days from placement), who presented after an unwitnessed fall, followed by confusion and amnesia. Pertinent laboratory examinations were negative. MRI of the brain showed edema with enhancement along the DBS electrode. Wound exploration revealed no infection. The DBS system was left in place; final cultures were negative; no antibiotics were prescribed. Repeat MRI showed resolving fluid-attenuated inversion recovery (FLAIR) signal and contrast enhancement. Conclusions: Contrast enhancement, T2 FLAIR, and diffusion weighted imaging are influenced by postoperative changes. Caution is stressed regarding dependence on these features for acute diagnosis of infection and indication for electrode removal. Timing of the imaging after surgery must be considered. Other factors, such as systemic signs and abnormal laboratory data, should be evaluated. Based on these guidelines, retrospectively, the patient in Case 2 should not have been rushed for a wound exploration; close observation with serial imaging and laboratory data may have prevented an unnecessary procedure. [ABSTRACT FROM AUTHOR]

Introduction: When time since stroke onset is unknown, DWI-FLAIR mismatch rating is an established technique for patient stratification. A visible DWI lesion without corresponding parenchymal hyperintensity on FLAIR suggests time since onset of under 4.5 h and thus a potential benefit from intravenous thrombolysis. To improve accuracy and availability of the mismatch concept, deep learning might be able to augment human rating and support decision-making in these cases., Methods: We used unprocessed DWI and coregistered FLAIR imaging data to train a deep learning model to predict dichotomized time since ischemic stroke onset. We analyzed the performance of Group Convolutional Neural Networks compared to other deep learning methods. Unlabeled imaging data was used for pre-training. Prediction performance of the best deep learning model was compared to the performance of four independent junior and senior raters. Additionally, in cases deemed indeterminable by human raters, model ratings were used to augment human performance. Post-hoc gradient-based explanations were analyzed to gain insights into model predictions., Results: Our best predictive model performed comparably to human raters. Using model ratings in cases deemed indeterminable by human raters improved rating accuracy and interrater agreement for junior and senior ratings. Post-hoc explainability analyses showed that the model localized stroke lesions to derive predictions., Discussion: Our analysis shows that deep learning based clinical decision support has the potential to improve the accessibility of the DWI-FLAIR mismatch concept by supporting patient stratification., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: More than a quarter of patients with ischemic stroke (IS) are excluded from thrombolysis because of an unknown time of symptom onset. Recent evidence suggests that a mismatch between diffusion-weighted imaging (DWI) and fluid attenuated inversion recovery (FLAIR) imaging could be used as a surrogate for the time of stroke onset. We compared used the DWI-FLAIR mismatch and the FLAIR/DWI ratio to estimate the time of onset in a group of patients with nocturnal strokes and unknown time of onset.Methods: We used a prospectively collected acute IS patient database with MRI as the initial imaging modality. Nineteen selected nocturnal stroke patients with unknown time of onset were compared with 22 patients who had an MRI scan within 6 hours from stroke onset (control A) and 19 patients who had an MRI scan between 6 and 12 hours (control B). DWI and FLAIR signal was rated as normal or abnormal. FLAIR/DWI ratio was calculated from independent DWI and FLAIR ischemic lesion volumes using semiautomatic software.Results: The DWI-FLAIR mismatch was different among groups (unknown 43.7%; control A 63.6%; control B 10.5%; Fisher-Freeman-Halton test; P = .001). There were significant differences in FLAIR/DWI ratio among the 3 groups (unknown 0.05 ± 0.12; control A 0.17 ± 0.15; control B 0.04 ± 0.06; Kruskal-Wallis test; P < .0001). Post-hoc pairwise comparisons revealed that FLAIR/DWI ratio from the unknown group was significantly different from the control B group (P = .0045) but not different from the control A group. DWI volumes were not different among the 3 groups.Conclusions: A large proportion of patients with nocturnal IS and an unknown time of stroke initiation have a DWI-FLAIR mismatch, suggesting a recent onset of stroke. [ABSTRACT FROM AUTHOR]

AIM: To compare T1-weighted magnetization transfer (MT) with fluid attenuated inversion recovery (FLAIR) imaging for evaluating conspicuity and number of lesions in individuals with brain tuberculoma. MATERIALS AND METHODS: In all 28 patients with brain tuberculoma underwent MR examination using fast spin-echo (FSE) T2, spin-echo (SE) T1, T1-weighted MT and FLAIR imaging. Post-contrast T1-weighted MT imaging was taken as the gold standard for assessing the number of lesions. Tuberculomas detected both on T1-weighted MT and FLAIR imaging were examined for the wall to be defined, and were divided into two groups on the basis of presence (group 1) or absence (group 2) of perilesional oedema visible on FLAIR imaging. The mean signal intensity of the wall of the lesions and adjacent oedema or brain parenchyma was analyzed qualitatively and quantitatively. RESULTS: The number of lesions detected on T1-weighted MT was higher than on FLAIR imaging (209 versus 163). Conspicuity in both groups was better on T1-weighted MT images qualitatively as well as quantitatively. The difference in the signal intensity of the wall of the lesion and perilesional oedema was statistically significant only on T1-weighted MT images in group 1 (p=0.0003 versus 0.3), whereas in group 2 it was statistically significant both on T1-weighted MT and FLAIR imaging (p=0.009 versus 0.05). CONCLUSION: FLAIR imaging is not helpful in the examination of brain tuberculomas compared with T1-weighted MT imaging, as it neither contributes to the characterization of lesion nor assesses the true disease load. [Copyright &y& Elsevier]

Sagittal and transverse fluid attenuated inversion recovery (FLAIR) images were obtained in age-matched 16 normal individuals, and 24 patients with obstructive hydrocephalus. The inner (inferior) callosal surface, which is covered by ependyma, was electronically measured ranging from 0.15 to 0.25 cm (mean=0.20±0.02 cm) in normal individuals. This region was thicker in hydrocephalus cases due to transcallosal accumulation of water, ranging from 0.29 to 1.10 cm (mean=0.65±0.30 cm). Furthermore, there was a prominent difference between mild hydrocephalus and moderate-to-severe hydrocephalus cases that in mild hydrocephalus the ranges were 0.29–0.40 cm (mean=0.34±0.03 cm), and in moderate-to-severe hydrocephalus the ranges were 0.50–1.10 cm (mean=0.80±0.22 cm). It is concluded that especially sagittal FLAIR images could be useful for identifying especially milder forms of hydrocephalus by evaluation of the appearance and thickness of the inner callosal layer. Twelve patients with moderate-to-severe obstructive hydrocephalus, and eight of the controls were studied with diffusion MRI, using the echo-planar trace imaging. In moderate-to-severe hydrocephalus patients apparent diffusion coefficient (ADC) values from the inner callosal surface were high, similar to that of transependymal resorption of water, ranging from 1.30 to 2.20×10−3 mm2/s (mean: 1.78±0.27×10−3 mm2/s), compared to the normal ADC values of the splenium in controls: 0.78±0.12×10−3 mm2/s. [Copyright &y& Elsevier]

Cortical dysplasia (CD) is the most epileptogenic structural lesion associated with epilepsy and patients with intractable seizures caused by this condition are good surgical candidates. MRI plays an important role in detecting the abnormalities of CD. We clarified the MRI characteristics of CD by comparing imaging and histological findings in 20 patients with intractable seizures who underwent surgical resection. There were 12 males and eight females, mean age at operation was 15 years. MRI was performed at 1.5 tesla; T1-weighted, T2- and proton density-weighted spin-echo and fluid-attenuated inversion-recovery (FLAIR) images were obtained. The lesions were in the frontal lobe in nine cases, temporal in two, occipital in another two, insular in one and multilobar in six. Blurring of the grey/white matter junction was seen in all patients, and T2 prolongation in white matter and/or at the grey/white matter junction in 19. Abnormal signal intensity was more frequent in the white matter or at the grey/white matter junction than in the grey matter. FLAIR images made this abnormal high signal easier to appreciate, and we thought them very useful in this context. In areas of T2 prolongation, we saw dysplastic neurones and/or balloon cells, dysmyelination, and ectopic neuronal clustering histologically; glial proliferation played an important role in prolonging T2. [ABSTRACT FROM AUTHOR]

Background Nipah virus (NiV) is re-emerging zoonotic RNA virus belonging to Paramyxoviridae family. Suspecting Nipah virus in a NiV naive tropical area is a challenge. NiV management is further confounded by acute presentation, high mortality, broad species tropism, multiple modes of transmission, difficulty to diagnose and lack of definitive treatment. Methods Recent NiV outbreak that lasted for approximately 1 month (2–29 May 2018) and resulted in 23 cases with a case-fatality rate of 91%. We present clinical summary and management of five cases managed at Baby Memorial Hospital, Kozhikode, India from May 17, 2018 to May 30, 2018 and were epidemiologically linked to the index case. All patients presented with initial nonspecific prodromal symptoms of fever, muscle pain, watery diarrhea. Median age was 53 years, four were males, median hospital stay was 3 days, median incubation period of was days. Further complications, included encephalitis with viral bronchopneumonia/acute respiratory distress syndrome (ARDS) in 100 %, patients, encephalitis with viral bronchopneumonia/ARDS with myocarditis in 60 %patients, despite attempted therapy with ribavirin all patients developed cardiorespiratory arrest and succumbed to the illness. Results Hematological Investigations showed normal TLC with a mean of 7,920 cells/ mm3, mild thrombocytopenia (mean 1,57,800) high Hb 16.12(SD1.10), ESR 19 mm/hr, DLC-N 82% high relative neutrophilic cytosis. Normal liver and renal function, Na+ 133 meq/L. CSF analysis showed high opening pressure, 100% lymphocytic pleocytosis, mean CSF sugar 118 mg/100mL, CSF protein 73.6. CT chest -bilateral airspace opacities and ground glassing. Brain FLAIR sequence showed nonspecific hyperintensities in white matter and brainstem correlating with vasculitic changes. Laboratory diagnosis of NiV was made by Real-Time RT–PCR on throat swab, blood, urine and cerebrospinal fluid by Manipal virus research center and National Institute of Virology. Pathological autopsy was done in 2 cases and found noncontributory. Conclusion We report clinical and public health management experience from one of the three hospitals managing the patients affected with NiV. Managing outbreaks of high infectivity requires persistent organized and committed healthcare interventions Disclosures All authors: No reported disclosures. [ABSTRACT FROM AUTHOR]

Background Progressive multifocal leukoencephalopathy (PML) is a rare demyelinating disease of white matter in the central nervous system (CNS) caused by reactivation of John Cunningham (JC) virus. Drug-induced PML is increasingly reported with the widely used biological immunosuppressant drugs and molecular targeted antineoplastic agents. Monoclonal antibodies were the pioneer drugs to be associated with PML including the prototypical natalizumab. Methods Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKI) have been rarely described in this context with few case reports of ibrutinib-associated PML. Osimertinib, a third-generation EGFR TKI, was recently FDA-approved for the first-line treatment of metastatic non-small-cell lung cancer (NSCLC), and to the best of our knowledge has never been associated with PML. We describe a case report of a rapidly progressive PML likely associated with osimertinib therapy. Results A 85-year-old female with history of NSCLC, on osimertinib, was admitted with progressively worsening left hemiparesis, facial palsy, unsteady gait, recurrent falls, and episodic confusion over a period of month. Brain magnetic resonance imaging revealed foci of non-enhancing increased T2 and fluid-attenuated inversion recovery (FLAIR) signal intensity in the periventricular and bilateral cerebral subcortical white matter. MRI cervical spine was unremarkable for acute enhancing lesions. Cerebrospinal fluid (CSF) was unremarkable for infectious etiology, oligoclonal bands, and cytology. The patient was readmitted 2 weeks later with worsening neurological deficits and new lesions in the bilateral middle cerebellar peduncles, pons, midbrain, and cerebral white matter. Positive CSF JC virus PCR lead to the final diagnosis of "probable" PML. Biopsy was deferred for high clinical suspicion of PML and procedural risks outweighing benefits. Osimertinib was likely contributing to PML in the absence of other immunosuppression. Conclusion Inhibition of tyrosine kinase-dependent pathways can potentially aid in the replication of JC virus per previously reported ibrutinib-associated PML. Clinicians should be aware of PML risk in patients on osimertinib and TKI therapy, especially those with positive serum JC virus serology. Disclosures All authors: No reported disclosures. [ABSTRACT FROM AUTHOR]

Background Monthly injectable CAB LA + RPV LA was noninferior to daily oral 3-drug antiretroviral therapy in HIV-1 virologically suppressed adults. CAB and RPV pharmacokinetics (PK) were assessed during the 48 Week maintenance period of the ATLAS and FLAIR Phase 3 studies. Methods Patients received oral CAB 30 mg + RPV 25 mg once daily for 4 weeks to assess individual tolerability prior to intramuscular (IM) injections of CAB LA 600 mg + RPV LA 900 mg followed by CAB LA 400 mg + RPV LA 600 mg every 4 weeks. Plasma CAB and RPV concentrations were measured pre-and post-dose at select visits using validated analytical methods. Results Baseline demographics for the pooled randomized ATLAS and FLAIR population (n = 591, LA arms) were: median age 38 years, 27% female, 18% African American, median BMI 25 kg/m2 (range: 15 – 51). CAB and RPV plasma concentrations at select visits are summarized in the table. After initial IM doses, mean CAB and RPV troughs were well above their respective in vitro PA-IC90 values (CAB, 0.166 μg/mL; RPV 12 ng/mL). At Week 48, mean CAB troughs were 17x PA-IC90 and between oral CAB 10–30 mg exposures. Similarly, mean RPV troughs were 7x PA-IC90 and remained within the exposure range following oral RPV 25 mg once daily. 80% of RPV steady-state was achieved by Week 48 and 100% for CAB by Week 44. Initial CAB concentrations in females and those with BMI ≥30 kg/m2 were lower due to slower absorption but this difference resolved by Week 48. For RPV, there was no absorption difference by gender or BMI. Conclusion CAB and RPV PK were consistent between studies achieving therapeutic concentrations within the first dosing interval that steadily increased over time through Week 48, for both males and females and irrespective of BMI. CAB LA + RPV LA provided compatible PK profiles following monthly IM dosing in a diverse patient population through 48 weeks. Disclosures All authors: No reported disclosures. [ABSTRACT FROM AUTHOR]

Background The studies on hypo-fractionation for GBM showed 5-12 months median overall survivals not inferior to standard fractionation protocols. We aimed to describe the feasibility of extreme hypo fractionation combined with temozolamide for newly diagnosed and recurrent GBM. Methods During Dec 2015- Dec 2017, 60 patients of biopsy proven GBM were retrospectively scrutinized and were analysed. PTV was defined on FLAIR/T2 signal coverage with 4 mm margin and GTV was defined as contrast enhanced tumor. PTV was prescribed with 5 Gy (range: 4.5-6 Gy) in five fractions at isocenter and GTV was prescribed as single fraction SRS as 8 Gy (range: 6-12 Gy) at 75% (range: 65-90%) isodose line. Radiation was completed in 8 days. Temozolamide was given as 100mg daily for 8 days. Results Mean age was 45 years (range: 22- 74 years). 40(66.66%) patients were male and 20(33.33%) were female. CR was found in 07 (11.66%) patients, PR was seen in 28 (46.66%) patients. SD was observed in 20 (33.33%) patients. 05 (8.33%) had PD during first 3-4 months. Treatment was tolerated very well. Only 5 patients used corticosteroids for 3 months. Median follow-up time was 24 months (range: 08-32 months). Median survival in newly diagnosed patients was 12.5 months (range: 4.5 -16 months), while in recurrent cases it was 8.5 months (range: 3 -11 months). Conclusions Extreme hypo-fractionation combined with temozolamide is safe and an effective approach to manage GBM cases and survivals are also comparable to the standard approaches. Further randomized studies are warranted to establish its regular use. Legal entity responsible for the study The authors. Funding Has not received any funding. Disclosure All authors have declared no conflicts of interest. [ABSTRACT FROM AUTHOR]

Background Adherence to antiretroviral therapy (ART) to treat HIV remains a critical global health challenge given its relationship with individual health outcomes and population-level transmission. Given barriers associated with oral ART adherence, and considerations of patients' preferences, long-acting injectable (LA) ART (cabotegravir + rilpivirine) is under development and has been shown to be non-inferior to daily oral ART in Phase III trials. While most of the trial participants have been men, as LA ART gets closer to becoming available for routine clinical use, it is critical to understand how this option is perceived by women. Methods We conducted in-depth interviews with 67 individuals, 53 people living with HIV (PLHIV) and 14 healthcare providers, in 11 sites in the United States and Spain participating in Phase III LA ART trials (ATLAS, ATLAS 2-M and FLAIR). Twenty percent (10/53) of trial participants interviewed were women. Interviews explored patient and provider perspectives and experiences with LA ART, and appropriate candidates and recommendations to support use. Interviews were audio-recorded, transcribed and coded using thematic content analysis. Results Overall, several salient themes emerged regarding participant's generally positive experiences transitioning from daily oral ART to injectable ART including: the importance of the clinical efficacy of LA ART, the ability to learn to manage injection side-effects over time, and the "freedom" reportedly afforded by LA ART logistically and psychosocially. Women interviewed shared many of the aforementioned positive perceptions of LA ART but also had some unique perspectives. Female participants discussed how LA ART was easier to integrate into their daily lives including managing their multiple roles and responsibilities, which often involved working full-time and taking care of themselves as well as their family and children. Conclusion Similar to all participants, female participants had generally positive views of LA ART. However, the gendered nature of their daily lives also led to some unique perspectives on why and how they were satisfied with LA ART that merits further exploration in future research. Disclosures All authors: No reported disclosures. [ABSTRACT FROM AUTHOR]

Background Cabotegravir (CAB) and rilpivirine (RPV) are under development as a novel long-acting (LA) regimen for maintenance of HIV virologic suppression. Pooled Week 48 data from pivotal Phase 3 trials demonstrated noninferiority of CAB LA + RPV LA vs. current antiretroviral regimen (CAR) on the primary endpoint, proportion of subjects with HIV-1 RNA ≥50 c/mL (1.9% and 1.7%, respectively). Adherence to dosing visits, use of oral dosing (bridging) to cover planned missed injections and injection tolerability were examined for subjects in the ATLAS and FLAIR studies. Methods Virologically suppressed subjects (HIV-1 RNA < 50 c/mL) were randomized to switch to CAB LA + RPV LA or to continue CAR. On-time injections occurred Q4 weeks within a + 7-day dosing window of the projected dosing date. Adherence to LA therapy was calculated as the number of on-time injection visits divided by the number of expected dosing visits through Week 48. Injection visits outside the pre-specified window and missed injection visits with/without the use of oral dosing were quantified. Injection tolerability was assessed via adverse event reporting. Results A total of 14,682 injections of CAB and RPV were administered to 581 subjects during 6,920 injection visits. 98% of injection visits took place within the allowed ±7-day dosing window with 3,194 (46%) on the projected dosing date. Forty-six (<1%) injection visits were early and 106 (2%) were late. Oral bridging was used in 16 subjects overall; 8 planned missed injection visits were successfully covered, with no change to virologic suppression status. No subject with HIV-1 RNA ≥ 50 c/mL at Week 48 had missed/late injection visits. 25% (3,663/14,682) of injections were associated with local injection site reactions (ISRs). The most common ISR was pain (3,087/3,663 = 84%). Most ISRs were grade 1–2 (99%), short duration (median 3 days), with few associated discontinuations (<1%). Conclusion Subjects receiving CAB LA + RPV LA demonstrated high rates of adherence to injection visits through week 48, with 98% of injections occurring within the ±7-day dosing window. Oral bridging with CAB and RPV was an effective strategy for maintaining viral load suppression to cover missed injection visits. Injections were well-tolerated with few associated discontinuations. Disclosures All Authors: No reported Disclosures. [ABSTRACT FROM AUTHOR]

Thymoma is one of the most common anterior mediastinal tumors in adults. The wide range of paraneoplastic syndromes associated with thymoma has been reported. There are few reported cases of thymoma associated with neuromyelitis optica spectrum disorder (NMOSD). We reported a 52-year-old man who was diagnosed with thymoma type B2 but loss follow-up. After 1 year, he developed subacute ascending paraparesis, bowel-bladder involvement without chest symptoms. The spinal cord syndrome was suspected from physical examination. The whole spine MRI showed multifocal short and long segments of hyperintense T2 lesion in C3/4, C5-1, T6-8, T10 levels. The cerebrospinal fluid revealed aseptic meningitis (WBC 100, lymphocyte 99%, neutrophil 1%, protein 60.8 mg/dL, normal glucose level) and negative for culture or PCR for viruses. The CSF aquaporin-4 were negative. However, the CSF paraneoplastic panel showed a positive for anti-titin. The brain MRI revealed an inhomogeneous isointense T2/FLAIR 1.7 x 2.2 cm at the left temporal lobe. The biopsy of temporal lesion reported as demyelinating disease. The NMOSD with the serology negative was diagnosed. He was treated with 5 days of intravenous methylprednisolone (1 gm/day) but his motor power was not improved. The plasmapheresis was initiated for 5 days. There was minimal improvement but his motor weakness worsened again. The multi-disciplinary team decided to treat underlying thymoma with chemotherapy. CAP regimen (cyclophosphamide 500 mg/m2, adriamycin 50 mg/m2 and paclitaxel 50 mg/m2) was administrated every 3 week for 4 cycles. His motor power and bowel-bladder function were gradually improved to full recovery. His chest CT showed decrease size of the thymoma. Thymoma could be associated with NMOSD. The treatment of thymoma should be considered to improve the neurological symptoms. [ABSTRACT FROM AUTHOR]

Objective Anaplastic astrocytoma is a rare malignant brain tumor occurring in adults aged 30 to 50, with an incidence of 5 to 8 people per 100,000. Cognitive dysfunction is a complication after tumor resection, resulting from neurotrauma of surgery, chemotherapy, and radiation treatment. Neural compensation and neuroplasticity can allow intact cognitive functioning after brain resection in brain areas expected to be impacted by the neurotrauma. Method The current case study is a 45-year-old female post -resection for dendritic cell vaccine clinical trial followed by adjuvant radiation of an anaplastic astrocytoma of the frontal lobe. MRI of the brain post right frontal craniotomy was indicative of extra-axial fluid communicating with the anterior aspect of the right lateral ventricle, hemosiderin along the medial resection margin, and T2/FLAIR signal abnormality in the left medial and right inferior frontal lobes. Results Test data revealed intact global cognitive functioning (WAIS-IV; FSIQ = 101 SS), with below expected performance on verbal comprehension (WAIS-IV; VCI = 98 SS). Consistent with the area of resection, she had impairments in visuoconstruction and executive functioning specific to mental generativity. However, performances with regard to math achievement were intact (WIAT; Math Problem Solving = 110 SS; Numerical Operations = 104 SS), despite significant neurotrauma to the prefrontal cortex. She also produced left lateralized fine motor weakness. Conclusions Accommodations for work, outpatient therapies, and psychotherapy were recommended. This case enhances the understanding of neurocognitive performance after neurotrauma involving tumor resection and radiation treatment in rare malignant brain tumor, and highlights the impact of neural compensation after resection. [ABSTRACT FROM AUTHOR]

Wake-up stroke, defined as patients who wake up with stroke symptoms which were not present prior to falling asleep, accounted for 14%-25% of acute ischemic stroke. Due to the unknown time of symptom onset, wake-up stoke was not in including criteria of intravenous thrombolysis. Several large randomized stroke trials using diffusion-weighted imaging(DWI)and fluid attenuated inversion recovery(FLAIR)mismatch patient selection may identify a subset of patients with wake-up stroke that can safely and effectively benefit from intravenous thrombolysis. In addition, economic factor was another important limitation to generalize thrombolysis treatment. Fortunately, MRI-based thrombolysis was a cost-effective treatment for wake-up stroke compared to these patients with no thrombolysis., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Magnetic resonance imaging is increasingly used in stroke trials for early diagnosis and follow-up of lesion size. Since volumetric measurement remains a laborious and time-consuming task, a rapid and reliable method for the assessment of lesion size has been developed and validated in diffusion weighted imaging (DWI) and fluid attenuated inversion recovery (FLAIR) sequences. These were serially obtained in 40 patients less than 8 h after the onset of symptoms of a middle cerebral artery territory stroke (day 1), as well as on days 3 and 18. For each of 16 (DWI) or 20 (FLAIR) transverse sections obtained on each occasion, lesion size was estimated as a percentage of the total hemisphere. Percentage values from all sections were summed up and expressed as arbitrary units. Results obtained using this approximate planimetric method (APM) were compared with those from a standard volumetric approach. Lesion volumes as determined by both methods were highly correlated (DWI: r=0.966, FLAIR: r=0.979, p<0.001). To conclude, the APM is simple, rapid and reliable for the estimation of lesion size in acute ischemic stroke. It can be recommended for broader application in clinical trials. [ABSTRACT FROM AUTHOR]

To improve the imaging protocol for the evaluation of endolymphatic hydrops after intravenous administration of a gadolinium-based contrast agent, we modified our previously reported hybrid of reversed image of positive endolymph signal and native image of positive perilymph signal (HYDROPS) method. Although the scan time of the new protocol was half that of the previous one, there were no significant differences between two protocols in the mean contrast noise ratio between the endolymph and perilymph and the area ratio of the endolymph size values in nine patients.

Background: Magnetic resonance imaging (MRI) of the brain is highly sensitive for detecting intracerebral hemorrhage (ICH). Understanding of the imaging characteristics of hyperacute ICH is limited secondary to availability and increased time to scan relative to other imaging modalities., Objective: In this report, we present the MRI characteristics of two patients who developed ICH while on the MRI table., Methods: A 44-year-old women presented with week-long headache associated with blurry vision and photophobia. A second patient, a 38-year-old woman, presented with headache. Both patients developed ICH while on the MRI table. We studied the imaging characteristics of hyperacute ICH in these two patients. Postcontrast T1 sequence obtained showed contrast extravasation from two spots in the right caudate nucleus with ventricular extension., Results: Hyperacute intracerebral hemorrhage has a characteristic appearance on MRI. The morphology of the hyperacute ICH that we presented confirms an asymmetric growth pattern. It also showed that the area of hemorrhage appeared to consist of multiple distinct compartments. These features suggested that expansion of ICH may be compounded by mechanical disruption of secondary blood vessels as the hematoma expanded. We can also confirm that hyperacute intraventricular hemorrhage can be revealed by gadolinium-enhanced MRI., Conclusion: MRI is able to detect hyperacute ICH and our findings demonstrate an asymmetric pattern of hematoma evolution. MRI with contrast is sensitive to detect hyperacute intraventricular hemorrhage.

Abstract: Fluid attenuated inversion recovery (FLAIR) and diffusion tensor imaging (DTI) techniques have been widely used to evaluate white matter (WM) alterations associated with aging, dementia and cerebral vascular disease. The relationship between FLAIR detected WM lesions (WML) and DTI detected WM integrity changes, however, remains unclear. To investigate this association, voxelwise correlations between 4 Tesla DTI and FLAIR images from elderly subjects were performed by relating WML volume and intensity in FLAIR to fractional anisotropy (FA) and mean diffusivity (MD) in DTI. Significant DTI–FLAIR correlations were found in regions overlapping with the WML of moderate intensities in FLAIR. No significant correlations were detected in periventricular regions where the FLAIR intensities are particularly high. The findings are consistent with a transitional model for WM degeneration from normal WM to cerebrospinal fluid (CSF). The results show that the correlation between DTI and FLAIR disappears when the FLAIR intensity of WML reaches its maximum at a certain lesion severity, and that the correlations may remerge with reversed signs when the lesion severity is further increased. These results suggest that the different stages of WM degeneration in elderly subjects can be better characterized by regional DTI–FLAIR correlations than single modality alone. [Copyright &y& Elsevier]

Track-Weighted Imaging (TWI), where voxel intensity is based on image metrics encoded along streamline trajectories, provides a mechanism to study white matter disease. However, with generalised streamline weighting, it is difficult to localise the precise anatomical source and spread of injury or neuropathology. This limitation can be overcome by modulating the voxel weight based on the distance of the voxel from a given anatomical location along the tract, which we term diTWI: distance informed Track-Weighted Imaging. The location of known neuropathology can be delineated on any given imaging modality (e.g. MRI or PET). To demonstrate the clinical utility of this approach, we measured tumour cell infiltration along WM fibre tracts in 13 patients with newly diagnosed glioblastoma and 1 patient with Anaplastic Astrocytoma. TWI and diTWI maps were generated using information obtained from dynamic contrast enhanced MRI (area under the curve, AUC) and diffusivity maps (ADC and FA) with tumour boundaries automatically extracted using a logistic regression classifier. The accuracy of the derived tumour volumes was compared to those generated using 3,4-dihydroxy-6-[(18)F]-fluoro-l-phenylalanine (FDOPA) PET imaging. The accuracy of the tumour volumes generated from the diTWI maps was superior to volumes derived from the TWI, geometric distance or baseline AUC, FA and ADC maps. The relative overlap and relative dissimilarity rates for the diTWI generated tumour volumes after classification were found to be 82.3±15.3% (range 69.1-91.9) and 16.9±8.8% (range 7.9-37.5), respectively. These findings show that diTWI maps provide a useful framework for localising neuropathological processes occurring along WM pathways., (© 2013.)