Intrasinus thrombolysis by mechanical and urokinase for severe cerebral venous sinus thrombosis : a case report.

PURPOSE: Cerebral venous and sinus thrombosis (CVST) is a rare stroke disorder, which requires prompt recognition and appropriate intervention to prevent a devastating outcome. Intrasinus thrombolysis is an alternative and effective method to anticoagulant therapy for the treatment of CVST, but is rarely used in Taiwan. CASE REPORT: A 46-year-old man presented with a one-week history of intractable headache and progressive weakness of his right lower limb. Magnetic resonance venography of the brain confirmed a diagnosis of extensive venous sinus thrombosis. The patient was successfully treated by direct intrasinus thrombolysis with urokinase. CONCLUSION: This case highlights the benefit of early intrasinus thrombolysis for the treatment of CVST.

Delayed parkinsonism after CO intoxication: evaluation of the substantia nigra with inversion-recovery MR imaging.

PURPOSE: To quantitatively investigate signal alterations of the substantia nigra in patients with delayed parkinsonism following CO intoxication, as seen on gray matter (GM)-suppressed inversion-recovery (IR) magnetic resonance (MR) images. MATERIALS AND METHODS: This prospective study was approved by the local institutional review board, and written informed consent was obtained from all subjects. Thirteen patients with delayed onset of CO-induced parkinsonism (nine men and four women; mean age, 40.3 years), 13 age-matched CO-intoxicated patients without parkinsonism, and 13 age-matched healthy volunteers were examined with GM-suppressed IR MR imaging. The signal intensity of the substantia nigra was normalized to the adjacent normal-appearing white matter in the temporal lobe, followed by semiautomatic segmentation into medial, middle, and lateral parts by using a skeleton-based algorithm. Multivariate and univariate analyses and Spearman rank correlation test were performed to examine the relationships between variables. Clinical severity was assessed with the modified Hoehn and Yahr rating scale. RESULTS: The normalized signal ratios in the middle and lateral segments of the substantia nigra were significantly higher in those with CO-induced parkinsonism, compared with those with CO intoxication without parkinsonism or normal volunteers (P=.02). For the medial segments, the ratios showed no significant differences among the groups. The normalized signal ratios of substantia nigra were correlated with the severity of parkinsonism, particularly in the lateral segments (ρ=0.927, P<.001). CONCLUSION: CO toxicity to the substantia nigra plays a role in pathophysiologic mechanisms of CO-induced parkinsonism. GM-suppressed IR MR imaging is a useful tool in depicting substantia nigra injury following CO intoxication.

Modifications to the McDonald MRI dissemination in space criteria for use in Asians with classic multiple sclerosis: the Taiwanese experience.

BACKGROUND: The McDonald MRI dissemination in space criteria have been found to be less sensitive when applied to Asians with classic multiple sclerosis. The Asian neurological community thus proposed modifications to the criteria with reduction of minimal number of T2 lesions from nine to four, and removal of restriction on spinal cord lesion length and morphology for use in Asians. OBJECTIVE: The study is to examine the accuracy of modified MRI dissemination in space criteria for prediction of conversion from clinically isolated syndrome to definite multiple sclerosis according to patients' baseline MRI. METHODS: From 2001 to 2007, we recruited 67 patients with clinically isolated syndrome. They had been followed-up until development of definite multiple sclerosis or remaining as clinically isolated syndrome for more than 2 years. The non-converters were taken as negative cases. The 67 patients' baseline MRIs were evaluated by two radiologists and determined as either fulfilling or not fulfilling McDonald and modified MRI criteria for dissemination in space. RESULTS: Thirty-two patients converted to definite multiple sclerosis and 35 did not. The modified criteria are slightly more sensitive (53.1% vs. 50.0%) and accurate (77.6% vs. 76.1%) as compared with McDonald criteria. However, further reduction of the cutoff of abnormal MRI criteria from three of four to two of four criteria yields best sensitivity (71.9%) and accuracy (83.6%). CONCLUSIONS: Modifications to the McDonald MRI dissemination in space criteria (by using fewer T2 lesions, removal of the restriction on the spinal cord lesion and reduction of the cutoff of MRI criteria) are more appropriate for use in the Taiwanese population for the diagnosis of classic multiple sclerosis.

Local intra-arterial thrombolysis with urokinase for acute ischemic stroke before and after the approval of intravenous tissue plasminogen activator treatment in Taiwan.

BACKGROUND: Local intra-arterial thrombolysis (LIT) has been previously suggested as an effective therapy for acute ischemic stroke. In this study, we describe our experience of using LIT for the treatment of Taiwanese patients with ischemic stroke at different vascular locations, before and after Alteplase was approved as a first-line treatment in Taiwan. The criteria required for the initiation of LIT have become more stringent after the approval of Alteplase (AA). METHODS: A retrospective analysis of medical records was conducted for 20 ischemic stroke patients treated with LIT; including 10 patients treated before and 10 patients treated after AA (we did not treat any of the patients in this study with AA). Urokinase was used for LIT treatment. Outcome measures included patient demographics, clinical characteristics, and clinical outcomes before and after LIT. Clinical outcomes were evaluated using four different stroke scales. RESULTS: The median National Institutes of Health stroke scale score (NIHSS) before treatment was reported to be 19.2 (range: 8-30). After AA, only one patient who had an occluded internal carotid artery (ICA) was treated with LIT. Among the 20 patients, 11 (55%) (five before AA and six after AA) reported having favorable or good clinical outcomes within 3 months of treatment, whereas five reported having poor outcomes (three before AA and two after AA), and the rest four patients died following treatment (two before AA and two after AA). Arterial recanalization was reported as complete in 10 patients (50%; seven middle cerebral artery [MCA] and three basilar artery; six before AA and four after AA), as incomplete in four patients (20%; one MCA and three basilar artery; one before AA and three after AA), and it failed in the remaining six patients (30%; two MCA and four ICA; three before AA and three after AA). Five patients (one MCA and four ICA) in whom recanalization had failed reported having poor outcomes, including one ICA patient who subsequently succumbed to the illness. Intracranial hemorrhagic and intraventricular hemorrhage transformation occurred in three and two patients, respectively. A case of intraventricular hemorrhage transformation after AA was also reported. CONCLUSION: On the basis of our experience, we found that LIT was of limited value in patients with ICA occlusion before AA approval. After AA, the outcomes in acute stroke patients, who were receiving urokinase therapy and who were carefully selected on the basis of the site of occlusion, were improved.

Salivary glands: echo-planar versus PROPELLER Diffusion-weighted MR imaging for assessment of ADCs.

PURPOSE: To compare the image distortion and the quantification variation in parotid gland apparent diffusion coefficients (ADCs) on periodically rotated overlapping parallel lines with enhanced reconstruction (PROPELLER) versus echo-planar diffusion-weighted (DW) magnetic resonance (MR) images and to investigate the relationship between parotid gland ADC and parotid gland fat content. MATERIALS AND METHODS: This prospective study was approved by a local institutional review board. Written informed consent was obtained from all 33 enrolled healthy volunteers (15 men, 18 women; mean age, 36.4 years +/- 11.8 [standard deviation]). All participants underwent 1.5-T non-fat-saturated and fat-saturated PROPELLER DW MR imaging as well as 1.5-T nonaccelerated and twofold-accelerated echo-planar DW MR imaging. Image distortion on the DW images was qualitatively scored, and parotid ADC was quantitatively analyzed. The correlation between parotid ADC and parotid fat content was evaluated by using linear regression analysis. Wilcoxon signed rank and t tests were used for statistical analysis, with Bonferroni correction applied for multiple comparisons. RESULTS: Echo-planar DW images showed distortion, which was completely eliminated on the PROPELLER DW images. The mean parotid ADCs measured with non-fat-saturated PROPELLER (0.670 x 10(-3) mm(2) +/- 0.149), nonaccelerated echo-planar (0.892 x 10(-3) mm(2) +/- 0.128), twofold-accelerated echo-planar (1.088 x 10(-3) mm(2) +/- 0.124), and fat-saturated PROPELLER (1.307 x 10(-3) mm(2) +/- 0.217) DW imaging differed significantly from one another (P < .001 for all comparisons). Parotid ADC had a significant negative correlation with parotid fat content (x) measured at non-fat-saturated PROPELLER DW imaging: ADC = -0.0087x + 1.1173 (r = 0.80, P < .001). CONCLUSION: PROPELLER DW imaging pulse sequences can yield distortion-free images for parotid ADC measurements and enable quantitative evaluation of the relationship between parotid ADC and parotid fat content. SUPPLEMENTAL MATERIAL: http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.2531082228/-/DC1.

Perfusion characteristics of late radiation injury of parotid glands: quantitative evaluation with dynamic contrast-enhanced MRI.

We aimed to quantitatively investigate the alteration of parotid perfusion after irradiation using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) based on a two-compartment tracer kinetic model. This study enrolled 19 patients (53.2 +/- 14.9 years) treated by head and neck radiotherapy and 19 age-relevant and sex-matched subjects as a control group. Perfusion parameters (K ( el ), k (21) and A) of parotid glands were analyzed based on the Brix model from T1-weighted DCE-MRI. Suitability of the Brix model was evaluated via Monte Carlo simulation for the goodness-of-fit. Analysis of nonlinear goodness-of-fit showed that the Brix model is appropriate in evaluating the parotid perfusion (R(2) = 0.938 +/- 0.050). The irradiated parotid glands showed significantly lower K ( el ) (P < 0.0005) and k (21) (P < 0.05) and consequently significantly higher value of peak enhancement (P < 0.0005) and time-to-peak (P < 0.0005) compared with non-irradiated ones, suggestive of gradual and prolonged accumulation and delayed wash-out of contrast agent due to increased extracellular extravascular space and decreased vascular permeability in the irradiated glands. Linear regression analysis showed dose-dependent perfusion changes of the irradiated parotid glands. We conclude that quantitative DCE-MRI is a potential tool in investigating parotid gland perfusion changes after radiotherapy.

Volume-dependent overestimation of spontaneous intracerebral hematoma volume by the ABC/2 formula.

BACKGROUND: Although the ABC/2 formula has been widely used to estimate the volume of intracerebral hematoma (ICH), the formula tends to overestimate hematoma volume. The volume-related imprecision of the ABC/2 formula has not been documented quantitatively. PURPOSE: To investigate the volume-dependent overestimation of the ABC/2 formula by comparing it with computer-assisted volumetric analysis (CAVA). MATERIAL AND METHODS: Forty patients who had suffered spontaneous ICH and who had undergone non-enhanced brain computed tomography scans were enrolled in this study. The ICH volume was estimated based on the ABC/2 formula and also calculated by CAVA. Based on the ICH volume calculated by the CAVA method, the patients were divided into three groups: group 1 consisted of 17 patients with an ICH volume of less than 20 ml; group 2 comprised 13 patients with an ICH volume of 20 to 40 ml; and group 3 was composed of 10 patients with an ICH volume larger than 40 ml. RESULTS: The mean estimated hematoma volume was 43.6 ml when using the ABC/2 formula, compared with 33.8 ml when using the CAVA method. The mean estimated difference was 1.3 ml, 4.4 ml, and 31.4 ml for groups 1, 2, and 3, respectively, corresponding to an estimation error of 9.9%, 16.7%, and 37.1% by the ABC/2 formula (P<0.05). CONCLUSION: The ABC/2 formula significantly overestimates the volume of ICH. A positive association between the estimation error and the volume of ICH is demonstrated.

(99m)Tc-TRODAT-1 and (123)I-IBZM SPECT studies in a patient with extrapontine myelinolysis with parkinsonian features.

Osmotic demyelination syndrome can result from the rapid correction of hyponatremia, and is categorized by central pontine myelinolysis and extrapontine myelinolysis (EPM). Magnetic resonance imaging (MRI) is currently the most useful modality for visualizing EPM lesions. However, MRI is unable to delineate the severity of involvement in the nigrostriatal dopaminergic pathway. The authors describe the case of a 48-year-old woman who developed isolated EPM with predominantly right-sided parkinsonian symptoms after rapid correction of hyponatremia. MRI revealed symmetrical demyelinating lesions in the bilateral striatum without central pontine involvement. (99m)Tc-TRODAT-1 and (123)I-iodobenzamide ((123)I-IBZM) single-photon emission computed tomography (SPECT) images showed unequally decreased uptake in the bilateral striatum. Treatment with carbidopa/levodopa improved the clinical parkinsonian symptoms. (99m)T(C)-TRODAT-1 and (123)I-IBZM SPECT images provide presynaptic and postsynaptic molecular information of the nigrostriatal dopaminergic pathway. The lesions demonstrated in the (99m)T(C)-TRODAT-1 and (123)I-IBZM SPECT images show higher correlation with the severity of clinical features in EPM than MRI, and the modalities may be useful in the evaluation of patients with parkinsonian symptoms.

A thrombophilic patient with a dural arteriovenous fistula presenting sensory aphasia and complicated with an acute pulmonary embolism.

BACKGROUND: Neuropsychiatric symptoms as the initial presentation of dural arteriovenous fistula (DAVF) are unusual. Anticoagulation therapy may be warranted for prevention of further thromboembolism if an underlying thrombophilia condition is diagnosed. CASE REPORT: We present a 70-year-old woman with sensory aphasia, who was diagnosed with a DAVF, Cognard type II a + b, by cerebral angiography. Her stroke-like syndrome resolved after transarterial embolization of the left occipital and middle meningeal arteries. Meanwhile, hypercoagulability was found because of hyperhomocysteinemia and the presence of a lupus anticoagulant. One month later, she suffered an acute pulmonary embolism and was started on anticoagulation therapy before stereotactic radiosurgery. CONCLUSION: Sensory aphasia may be the initial manifestation of a transverse-sigmoid sinus DAVF even if there are no symptoms such as headache or tinnitus. We postulate that early anticoagulation therapy is indicated for preventing thromboembolism in DAVF patients with thrombophilia because the possibility of intracranial bleeding has been reduced by embolization.

Brain injury after acute carbon monoxide poisoning: early and late complications.

OBJECTIVE: The purposes of this article are to illustrate the variable CT and MRI features of carbon monoxide-induced brain injury and to discuss the underlying pathogenesis. CONCLUSION: Carbon monoxide can produce different patterns of brain injury in the acute and delayed stages. CT and MRI are valuable in the delineation of disease extent and helpful for understanding the pathophysiologic mechanisms.

Diffusion-weighted magnetic resonance imaging of spontaneous venous infarction and cortical hemorrhage complicating dural arteriovenous fistula.

Dural arteriovenous fistula (DAVF) is an abnormal arteriovenous shunt that occurs in the dura matter within or near a dural sinus. The clinical manifestations vary. The authors report herein a rare case of type III DAVF presenting with coexisting intracranial hemorrhage (ICH) and venous infarction evidenced by computed tomography (CT) and diffusion-weighted magnetic resonance imaging. Conventional angiography proved that the right middle meningeal artery and the occipital artery supplied the DAVF, with direct drainage into the cortical veins and superior sagittal sinus.

Hippocampal alterations in children with temporal lobe epilepsy with or without a history of febrile convulsions: evaluations with MR volumetry and proton MR spectroscopy.

BACKGROUND AND PURPOSE: The causal effect of early febrile convulsions (FC) on later-onset temporal lobe epilepsy (TLE) remains unclear. In this study, we sought to examine the hippocampal alterations in epileptic children with or without FC history by using MR spectroscopy and volumetry. METHODS: Fifty-five children ranging in age from 18 months to 15 years were enrolled in this study. Subjects were divided into three groups: the control group without either TLE or history of FC (n = 16), the TLE group with early history of FC (TLE + FC; n = 22), and the TLE group without FC history (n = 17). Measurement of hippocampal volume (HV) was performed on thin section T1-weighted images acquired with a 3D gradient echo MR image and normalized by the intracranial volume. Each individual subject had two measures of lateralization; one gives the smaller side of HV and the other the contralateral larger side of HV, assuming that the side with smaller HV is the possible primary site of seizure focus and the contralateral larger HV the secondary or normal site. Single-voxel proton MR spectroscopy of the hippocampi was performed, with metabolic ratio n-acetylaspartate (NAA)/choline (Cho) + creatine plus phosphocreatine (Cr) calculated and grouped separately as were with volumetry. RESULTS: The overall mean HV for the control group was 2.61 +/- 0.21 cm(3) at an average intracranial volume of 965 +/- 241 cm(3), and the asymmetry index for hippocampal volume was (2.32 +/- 1.58)%. The overall mean HV was 2.30 +/- 0.33 cm(3) for TLE + FC group and 2.34 +/- 0.33 cm(3) for TLE group. Mean HV differed significantly for the three groups (P < .01). When the small and large sides were analyzed separately, significant differences were found between control and TLE as well as between control and TLE + FC for the smaller side (P < .05), whereas for the larger side significant differences were found only between control and TLE + FC. In MR spectroscopic measurements, the mean NAA/(Cr + Cho) of bilateral hippocampi was 0.77 +/- 0.06 for control group, 0.62 +/- 0.12 for TLE + FC group, and 0.66 +/- 0.11 for TLE group. In terms of statistically significant difference between groups, spectroscopic results were similar to volumetric measurements, except that there was no significant interaction effect between groups and measures of asymmetrical indices (P = .272). CONCLUSION: Children with TLE and early history of FC tend to have lower hippocampal volumes and NAA/(Cr + Cho) ratios than do TLE children without FC history. The TLE + FC group seems to have increased vulnerability of the contralateral hippocampus as compared with TLE group. MR volumetry and spectroscopy are equally capable of showing the trends of hippocampal alternations in children with TLE with or without FC history.

Retrospective study using MRI to measure depths of acupuncture points in neck and shoulder region.

OBJECTIVES: There are safety issues associated with acupuncture treatment. Previous studies regarding needling depth of acupuncture points revealed inconsistent results due to vague depth definition, acupuncture point localisation and measuring tools. The objective of this study is to find and compare the differences of the mean depths of 11 acupuncture points in the neck and shoulder region between subjects, with variables including gender and body mass index (BMI). SETTING: This study was conducted at a single medical center in Taiwan. PARTICIPANTS: Three hundred and ninety-four participants were included in this study. Participants were grouped according to gender and BMI. Acupuncture points were localised by WHO standard and measured by MRI. OUTCOME MEASURES: The distance from the needle insertion point (surface of the skin) to any tissues that would cause possible/severe complications. RESULTS: Mean depths of 11 points were obtained in groups of different BMI and gender. Mean depths of all participants regardless of BMI and gender are as follows, in centimetres: GB21=5.6, SI14=5.2, SI15=8.8, GV15=4.9, GV16=4.6, GB20=5.0, ST9=1.6, SI16=1.8, SI17=2.4, TE16=3.1, LI18=1.3. Participants with higher BMI had greater measured depths in both gender groups. Male participants had larger mean depths than female participants regardless of BMI except in SI17 and LI18. When taking BMI into consideration, depths in male participants are greater than in female participants in most of the points except the following: GB21, TE16 in obesity group; ST9 in underweight and obesity group; SI16 in ideal body weight, overweight and obesity group; SI17, LI18 in each group. CONCLUSIONS: Participants with higher BMI had greater measured depths and males tended to have greater depths in most of the points. Clinical practitioners are recommended to consider this information to prevent complications when applying acupuncture treatment to their patients.

Disappearing calvarium in Gorham disease: MR imaging characteristics with pathologic correlation.

Gorham disease is a rare condition characterized by intraosseous neoplastic proliferation of hemangiomatous tissue with progressive, massive osteolysis. We present a pathologically proved case of Gorham disease that involved the left parietal bone in a 23-year-old man. Imaging studies including conventional radiography of the skull, CT, MR imaging, and Technetium-99 m (Tc-99 m) scintigraphy demonstrated a large skull defect without associated soft tissue mass over the left parietal skull. Contrast enhancement and increased isotope uptake along the margin of the defect were shown at gadolinium-enhanced T1-weighted MR imaging and Tc-99 m methylene diphosphate (Tc-99 m MDP) bone scintigraphy. Pathologic study revealed intraosseous angiomatosis at the periphery of the osteolytic skull lesion.

Discrepant MR spectroscopic and perfusion imaging results in a case of malignant transformation of cerebral glioma.

We present serial MR perfusion and spectroscopic findings of a pathologically proved low grade glioma, which evolved into glioblastoma multiforme in 2 years in a 24-year-old man. The initial MR imaging studies, including enhanced conventional T1-weighted and perfusion imaging, were characteristic of a benign glioma with the only exception being that multi-voxel proton MR spectroscopy showed malignant features with a high choline:phosphocreatine ratio. Postoperative follow-up MR imaging revealed findings consistent with malignant glioma, with increased angiogenesis on perfusion images and heterogeneous enhancement on contrast-enhanced T1-weighted images that were further confirmed by second surgery. We suggest conducting close MR imaging follow-up of patients with glioma who have discrepant MR spectroscopic and perfusion results after treatment.

Parasellar solitary fibrous tumor of meninges: magnetic resonance imaging features with pathologic correlation.

Solitary fibrous tumor (SFT) is a benign mensenchymal neoplasm of spindle-cell origin. The authors report the case of a 50-year-old man with SFT arising from the meninges of the left parasellar region with cavernous sinus involvement. The tumor was demonstrated isointense on T1-weighted and heterogeneously hypointense on T2-weighted magnetic resonance imaging (MRI) with strong contrast enhancement. The preoperative MRI diagnosis was meningioma or hemangiopericytoma. Pathological study revealed an SFT that stained positive immunohistochemically for CD34 and vimentin.

Hematoma shape, hematoma size, Glasgow coma scale score and ICH score: which predicts the 30-day mortality better for intracerebral hematoma?

PURPOSE: To investigate the performance of hematoma shape, hematoma size, Glasgow coma scale (GCS) score, and intracerebral hematoma (ICH) score in predicting the 30-day mortality for ICH patients. To examine the influence of the estimation error of hematoma size on the prediction of 30-day mortality. MATERIALS AND METHODS: This retrospective study, approved by a local institutional review board with written informed consent waived, recruited 106 patients diagnosed as ICH by non-enhanced computed tomography study. The hemorrhagic shape, hematoma size measured by computer-assisted volumetric analysis (CAVA) and estimated by ABC/2 formula, ICH score and GCS score was examined. The predicting performance of 30-day mortality of the aforementioned variables was evaluated. Statistical analysis was performed using Kolmogorov-Smirnov tests, paired t test, nonparametric test, linear regression analysis, and binary logistic regression. The receiver operating characteristics curves were plotted and areas under curve (AUC) were calculated for 30-day mortality. A P value less than 0.05 was considered as statistically significant. RESULTS: The overall 30-day mortality rate was 15.1% of ICH patients. The hematoma shape, hematoma size, ICH score, and GCS score all significantly predict the 30-day mortality for ICH patients, with an AUC of 0.692 (P = 0.0018), 0.715 (P = 0.0008) (by ABC/2) to 0.738 (P = 0.0002) (by CAVA), 0.877 (P<0.0001) (by ABC/2) to 0.882 (P<0.0001) (by CAVA), and 0.912 (P<0.0001), respectively. CONCLUSION: Our study shows that hematoma shape, hematoma size, ICH scores and GCS score all significantly predict the 30-day mortality in an increasing order of AUC. The effect of overestimation of hematoma size by ABC/2 formula in predicting the 30-day mortality could be remedied by using ICH score.

Acute bilateral hearing loss as a "worsening sign" in a patient with critical basilar artery stenosis.

We report a patient who presented with an acute-onset transient vertigo and unsteady gait with bilateral hearing loss. Brain MRI revealed a critical basilar artery (BA) stenosis at the lower pons and infarction in various areas on both sides in the territories of the posterior inferior cerebellar arteries (PICA). Further, we could not visualize the right anterior inferior cerebellar artery (AICA). The bilateral hearing loss may be ascribed to stroke due to the critical BA stenosis, causing hypoperfusion injury extending from the PICA to the AICA on both sides. Local intra-arterial thrombolytic therapy with the administration of 1×10(6) IU of urokinase aided partial recanalization of the BA, after which the right AICA reappeared. The neurological function of the patient recovered to normal, and no hemorrhagic complications were observed. Therefore, practitioners should be alert when treating patients with acute bilateral hearing loss, which may be related to an underlying catastrophic stroke.

Comparison of the 2010 and 2005 versions of the McDonald MRI criteria for dissemination-in-time in Taiwanese patients with classic multiple sclerosis.

In 2010, the International Panel on the Diagnosis of Multiple Sclerosis revised the 2005 version of the McDonald criteria. The revisions to MRI dissemination-in-time criteria include adoption of a new criterion by demonstration of simultaneous asymptomatic gadolinium-enhancing and nonenhancing lesions on baseline MRI scans. The purpose of this study was to demonstrate the diagnostic validity of the modified MRI dissemination-in-time criteria. We collected 80 patients with an initial clinical attack suggestive of an acute central nervous system demyelinating disease. The patients were followed for at least two years or until the development of definite multiple sclerosis. The nonconverters were taken as negative cases. Their baseline and follow-up brain MRI studies were retrospectively reviewed by two neuroradiologists. The 2010 version had higher sensitivity (68.2% vs. 45.5%), slightly lower specificity (80.6% vs. 83.3%), and higher accuracy (73.8% vs. 62.5%) than the 2005 version, but the differences were without statistical significance. The new criteria are more sensitive and accurate and specific just as the old criteria. They allow the diagnosis of definite multiple sclerosis in 34.1% patients at first presentation of the clinically isolated syndrome.

Do aggressive imaging features correlate with advanced histopathological grade in meningiomas?

Atypical and malignant meningiomas are more likely to recur than benign meningiomas. We aimed to distinguish atypical and malignant meningiomas from benign meningiomas based on imaging findings. Between 2004 and 2007, a total of 75 patients with resected intracranial meningiomas were retrospectively reviewed. Histopathological grades were assigned as benign and atypical/malignant meningiomas according to the World Health Organization (WHO) classification. All patients received preoperative CT scans and MRI studies. Six aggressive imaging features were evaluated and compared between the two groups: (i) intratumoral cystic change; (ii) hyperostosis of the adjacent skull; (iii) bony destruction; (iv) extracranial tumor extension through the skull base foramina; (v) arterial encasement; and (vi) peritumoral brain edema. There were 59 benign and 16 atypical/malignant meningiomas. Only intratumoral cystic change and extracranial tumor extension through the skull base foramina were more prevalent in atypical/malignant meningiomas (p=0.001). Hence, these two imaging features might be potential markers of atypical/malignant meningiomas.