Aberrant Origin of the Distal Anterior Cerebral Artery from the Middle Cerebral Artery Related to Obstruction of Bilateral Proximal Anterior Cerebral Arteries: A Case Report.

BACKGROUND: Aberrant origin of the distal anterior cerebral artery (ACA) arising from the middle cerebral artery (MCA) is extremely rare. CASE PRESENTATION: A 74-year-old woman with a sudden onset of left-sided weakness was admitted to the emergency department. Angiography revealed an unusual course of the distal ACA originating from the MCA with bilateral obstruction of the proximal segment of the ACA and simultaneous occurrence of infarction in the ACA and MCA territories. CONCLUSION: Knowledge of a rare vascular variation or anomaly could help understand brain imaging, which has an unusual involvement of vascular territories, performed in patients with acute ischemic stroke.

Clinical significance of asymmetric hypointense signals in minimum intensity projections of brain magnetic resonance imaging in children with primary headache.

PURPOSE: This study aimed to observe the changes of venous continuity using the susceptibility weighted imaging-minimum intensity projection (SWI-MinIP) images in children with primary headache. METHODS: The headache types were classified following the International Headache Society's diagnostic criteria. Patients with secondary headaches were excluded. The presence of asymmetric vasculature in SWI-MinIP images was visually assessed. Moreover, the relationship between headache patterns and asymmetric hypointense signals was analyzed. RESULTS: In this single-center, retrospective study from 2016 to 2020, among 251 cases of primary headache (male/female, 108/143; mean age, 11.4 ± 4.0 years), 137 (54.6%), 75 (29.9%), and 39 (15.5%) patients had migraine, tension-type headache, and other primary headaches, respectively. On SWI-MinIP images, 14 (5.6%) patients showed an asymmetric venous pattern. All patients with SWI-MinIP asymmetry were included in the migraine group, accounting for 10.2% of patients with migraine. Five (35.7%) and nine (64.3%) patients were included in the aura and non-aura groups, respectively, without a significant difference in the frequency of asymmetric hypointense signals between the two groups (p = 0.325). All 14 patients with asymmetric hypervascularity had brain MRI within 12 h of headache onset. Ten (71.4%) of the 14 patients showed consistency between the laterality of headache and the hemisphere of predominant vascularity in SWI-MinIP. CONCLUSION: Patients with migraine had increased cerebral venous perfusion in the most involved region of the headache on the SWI-MinIP view on a 3.0 T scanner, which can be used as a qualitative indicator with low sensitivity and high specificity for the diagnosis of primary headache in the acute phase (< 12 h).

Case report: Bilateral posterior ischemic optic neuropathy in a patient with atrial fibrillation and multifocal embolic stroke.

An 80-year-old female with a history of diabetes mellitus (DM) and hypertension presented with sudden onset of sequential bilateral visual loss. The best visual acuity was light perception in the right eye and finger counting in the left eye, however, bilateral fundus did not reveal optic disc edema. Diffusion-weighted magnetic resonance imaging (MRI) of the brain revealed acute embolic stroke and diffusion restriction in the posterior portion of both optic nerves. The 24-h Holter monitor showed persistent atrial fibrillation (AF) with rapid ventricular response. The presence of painless and severe visual loss at onset unaccompanied by optic disc edema in the patient with newly detected uncontrolled AF and multiple embolic infarctions favored a diagnosis of non-arteritic posterior ischemic optic neuropathy (PION). The current case contributes to better understanding of PION pathophysiology and associated risk factors, indicating a possible relationship between non-arteritic PION and uncontrolled AF and embolic cerebral infarction.

Endolymphatic Hydrops in Patients With Vestibular Migraine and Concurrent Meniere's Disease.

Objective: Intravenous contrast agent enhanced, high-resolution magnetic resonance imaging of the inner ear (iMRI) confirmed that patients with Menière's disease (MD) and vestibular migraine (VM) could present with endolymphatic hydrops (EH). The present study aimed to investigate EH characteristics and their interrelation to neurotologic testing in patients with VM, MD, or VM with concurrent MD (VM-MD). Methods: Sixty-two patients (45 females, aged 23-81 years) with definite or probable VM (n = 25, 19 definite), MD (n = 29, 17 definite), or showing characteristics of both diseases (n = 8) were included in this study. Diagnostic workup included neurotologic assessments including video-oculography (VOG) during caloric stimulation and head-impulse test (HIT), ocular and cervical vestibular evoked myogenic potentials (o/cVEMP), pure tone audiometry (PTA), as well as iMRI. EH's degree was assessed visually and via volumetric quantification using a probabilistic atlas-based segmentation of the bony labyrinth and volumetric local thresholding (VOLT). Results: Although a relevant number of VM patients reported varying auditory symptoms (13 of 25, 52.0%), EH in VM was only observed twice. In contrast, EH in VM-MD was prevalent (2/8, 25%) and in MD frequent [23/29, 79.3%; χ2(2) = 29.1, p < 0.001, φ = 0.7]. Location and laterality of EH and neurophysiological testing classifications were highly associated (Fisher exact test, p < 0.005). In MD, visual semi-quantitative grading and volumetric quantification correlated highly to each other (r S = 0.8, p < 0.005, two-sided) and to side differences in VOG during caloric irrigation (vestibular EH ipsilateral: r S = 0.6, p < 0.05, two-sided). In VM, correlations were less pronounced. VM-MD assumed an intermediate position between VM and MD. Conclusion: Cochlear and vestibular hydrops can occur in MD and VM patients with auditory symptoms; this suggests inner ear damage irrespective of the diagnosis of MD or VM. The EH grades often correlated with auditory symptoms such as hearing impairment and tinnitus. Further research is required to uncover whether migraine is one causative factor of EH or whether EH in VM patients with auditory symptoms suggests an additional pathology due to MD.

Susceptibility-Weighted Imaging as a Distinctive Imaging Technique for Providing Complementary Information for Precise Diagnosis of Neurologic Disorder.

Various sequences have been developed for MRI to aid in the radiologic diagnosis. Among the various MR sequences, susceptibility-weighted imaging (SWI) is a high-spatial-resolution, three-dimensional gradient-echo MR sequence, which is very sensitive in detecting deoxyhemoglobin, ferritin, hemosiderin, and bone minerals through local magnetic field distortion. In this regard, SWI has been used for the diagnosis and treatment of various neurologic disorders, and the improved image quality has enabled to acquire more useful information for radiologists. Here, we explain the principle of various signals on SWI arising in neurological disorders and provide a retrospective review of many cases of clinically or pathologically proven disease or components with distinctive imaging features of various neurological diseases. Additionally, we outline a short and condensed overview of principles of SWI in relation to neurological disorders and describe various cases with characteristic imaging features on SWI. There are many different types diseases involving the brain parenchyma, and they have distinct SWI features. SWI is an effective imaging tool that provides complementary information for the diagnosis of various diseases.

Why is middle cerebral artery plaque augmented by contrast media? A phantom study using middle cerebral artery stenotic silicon model.

PURPOSE: The pathophysiologic mechanisms of contrast enhancement (CE) of middle cerebral artery (MCA) plaque remain unclear since histologic and imaging findings have never been compared. The purpose of this study was to assess the pattern of CE between patients with MCA stenosis or occlusion and in an MCA stenotic silicone model. METHODS: We retrospectively reviewed black blood (BB) contrast-enhanced T1-weighted (CE-T1W) imaging of patients who presented with acute stroke symptoms between January 2017 and January 2018. We subdivided the enrolled subjects according to whether the cerebral angiography findings suggested stenosis or occlusion. Silicone models were made with 4 degrees of MCA stenosis (stenotic area: 0.8 mm, 1.0 mm, 1.2 mm, and 1.4 mm) with a 3-mm lumen. BB CE-T1W imaging on silicone models with stenosis was obtained 5 min after contrast injection. RESULTS: During the period of this study, 19 patients with complete MCA occlusion and 22 with MCA stenosis, as shown by the cerebral angiography, were enrolled in this study. The CE of the silicone models with stenosis were 0.8 (74%) mm and 1.0 (66.7%) mm. The SI ratios of the CE of the plaque and the lumen were similar between the silicone models and the MCA stenosis/occlusion groups (silicone models: 31.0 ± 11.2; MCA occlusion: 27.6 ± 19.6; MCA stenosis: 22.8 ± 9.8). CONCLUSION: The silicone stenotic MCA model was characterized by luminal enhancement through contrast stagnation. The findings of the CE of the MCA plaque may be partially associated with stagnation of the contrast media.

Epithelioid sarcoma arising from the temporal space: A case report.

INTRODUCTION: Epithelioid sarcoma is a malignant soft tissue tumor arising from mesenchymal tissue and usually occurs in the extremities. The tumor involving the head and neck region is extremely rare. We present radiologically well-documented case of an epithelioid sarcoma arising from the temporal space. CASE PRESENTATION: A 35-year-old woman presented with a slowly growing, painless palpable mass in the left temporal area. Ultrasound (US) revealed a lobulated hypoechoic mass with internal vascularity. On magnetic resonance (MR) imaging, the mass showed heterogeneous signal intensity with a central necrotic area and peritumoral infiltration. On the basis of the clinical and radiological characteristics, the lesion was considered to be a malignant tumor originating from soft tissue. An incisional biopsy was performed. The diagnosis of epithelioid sarcoma was based on microscopic examination and immunohistochemical analysis. F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) was used to stage the tumor and demonstrated intense FDG uptake in the mass without regional lymph node or distant metastasis. After the pathologic diagnosis of epithelioid sarcoma, the patient underwent total surgical resection of the tumor followed by postoperative irradiation. There was no evidence of recurrent disease during the follow-up period of 18 months. CONCLUSION: An epithelioid sarcoma should be considered in the differential diagnosis of a locally aggressive lesion occurring in the temporal space of head and exhibiting a heterogeneous appearance on imaging studies, including a central necrotic area and signal intensity suggestive of infiltration of soft tissue adjacent to the tumor. It is, however, true that head-and-neck involvement is very rare, and the radiological findings are not pathognomonic.

The Prognostic Value of CT-Angiographic Parameters After Reperfusion Therapy in Acute Ischemic Stroke Patients With Internal Carotid Artery Terminus Occlusion: Leptomeningeal Collateral Status and Clot Burden Score.

BACKGROUND: The objective of this study was to investigate the prognostic value of computed tomographic angiography (CTA) based on leptomeningeal collateral (LMC) status and other parameters in acute ischemic stroke (AIS) patients with internal carotid artery (ICA) terminus occlusion treated with endovascular treatment (EVT). METHODS: All eligible patients from January 2013 to December 2017 undergoing EVT were retrospectively reviewed. The regional leptomeningeal score was used to assess the LMCs on baseline CTA. The collateral status measured by the LMC score (0-20) was trichotomized into 3 groups: good (17-20), intermediate (11-16), and poor (0-10). RESULTS: Our sample included a total of 119 eligible patients (60 males; mean age, 73 years) with a median baseline National Institute of Health Stroke Scale (NIHSS) score of 14. Patients with a good LMC score had a lower baseline mean NIHSS score, a higher mean Alberta Stroke Program Early CT score, and a higher mean clot burden score (CBS). Baseline NIHSS score <15 (odds ratio [OR] 3.69 95% confidence ratio [CI]: 1.32-10.29, P = .013), CBS ≥ 6 (OR 3.97 95%CI: 1.05-14.99, P = .042), good LMC score (OR 5.14 95%CI: 1.62-16.26, P = .005) and successful recanalization (OR 11.55 95%CI: 2.72-48.99 P = .001) were independent predictors of good clinical outcomes. CONCLUSIONS: CTA-based LMC status and CBS are powerful predictors of clinical outcomes in patients with an acute ICA terminus occlusion treated with EVT.

Swallowing outcomes in patients with subcortical stroke associated with lesions of the caudate nucleus and insula.

Objective The present study was performed to investigate the relationships between swallowing outcomes and lesion location, bolus characteristics, and age in patients with subcortical stroke. PATIENTS: Patients with subcortical and insular stroke (mean age, 57.38 ± 12.71 years) were investigated. All patients (n = 21) completed both brain magnetic resonance imaging studies and videofluoroscopic swallowing studies. Main Outcome Measures The oral transit duration, pharyngeal transit duration (PTD), laryngeal response duration, and Penetration-Aspiration Scale (PAS) score were applied to examine the efficiency of propulsion and airway protection in three swallowing tasks. Path analyses were performed to assess the relationships between swallowing outcomes and lesion location, age, bolus viscosity, and bolus volume. Results Caudate nucleus (CN) lesions were associated with higher PAS scores. Insular lesions were associated with a longer PTD. Advanced age was associated with a longer PTD. Bolus viscosity significantly moderated the association between CN lesions and higher PAS scores. Conclusions In the present cohort, CN lesions impacted airway protection and insular lesions impacted pharyngeal transit. An increased bolus viscosity reduced the aspiration severity. These results suggest that lesion location is an important indicator to predict subsequent dysphagia in patients with subcortical stroke.

Detection of small brain metastases at 3 T: comparing the diagnostic performances of contrast-enhanced T1-weighted SPACE, MPRAGE, and 2D FLASH imaging.

The aim of this study was to compare the diagnostic performance of contrast-enhanced T1-weighted sampling perfection with application-optimized contrasts using different flip angle evolutions (SPACE), magnetization-prepared rapid gradient-echo (MPRAGE), and two-dimensional (2D) fast low angle shot (FLASH) for the detection of small brain metastases. Twelve patients who had brain metastases less than 10 mm in diameter were enrolled. The diagnostic performance was evaluated using alternative free-response receiver operating characteristic analysis. Sensitivity and positive predictive value were also calculated. The mean Az and sensitivities of SPACE for all observers were significantly higher than those of MPRAGE and 2D FLASH.

Ocular vestibular evoked myogenic potentials induced by air-conducted sound in patients with acute brainstem lesions.

OBJECTIVE: The ocular vestibular-evoked myogenic potential (oVEMP), a recently documented otolith-ocular reflex, is considered to reflect the central projections of the primary otolithic afferent fibers to the oculomotor nuclei. The aim of our study is to define air-conducted sound oVEMP abnormality in patients with acute brainstem lesions and to determine the brainstem structures involved in the generation of oVEMPs. METHODS: In response to air-conducted tone burst sounds (ACS), oVEMP was measured in 52 patients with acute brainstem lesions. Individualized brainstem lesions were analyzed by means of MRI-based voxel-wise lesion-behavior mapping, and the probabilistic lesion maps were constructed. RESULTS: More than half (n=28, 53.8%) of the patients with acute brainstem lesions showed abnormal oVEMP in response to ACS. The majority of patients with abnormal oVEMPs had lesions in the dorsomedial brainstem that contains the medial longitudinal fasciculus (MLF), the crossed ventral tegmental tract (CVTT), and the oculomotor nuclei and nerves. CONCLUSION: MLF, CVTT, and the oculomotor nuclei and nerves appear to be responsible for otolith-ocular responses in the brainstem. SIGNIFICANCE: Complemented to cervical VEMP for the uncrossed otolith-spinal function, oVEMP to ACS may be applied to evaluate the crossed otolith-ocular function in central vestibulopathies.

Corticospinal tract and pontocerebellar fiber of central pontine myelinolysis.

Central pontine myelinolysis is a rare neurologic disorder that is defined by demyelination of longitudinally descending tracts and transversly crossing fibers in the basis pontis. Frequently observed clinical manifestations of this disorder include sudden weakness, dysphagia, loss of consciouness and locked-in syndrome. However, there have been a few studies that reported a benign course of this disease, which include cerebellar signs, such as ataxia, intention tremor, and dysarthria. Here we report on a 53-year-old male with a history of liver cirrhosis who showed the cerebellar type of central pontine myelinolysis. The patient was diagnosed with central pontine myelinolysis based on clinical presentations and magnetic resonance imaging findings after a liver transplantation. Conventional magenetic resonance imaging (MRI) revealed the preservation of the corticospinal tract and abnormal pontocerebellar fibers. However, these findings were not sufficient to define the pathophysiology of our patient. Electrophysiologic analysis and diffusion tensor imaging (DTI) were performed to investigate cerebellar signs in this case. Delayed central motor conduction time (CMCT) to the tibialis anterior muscle with transcranial magnetic stimulation (TMS) was observed, which indicated demyelination of the corticospinal tract. Also, diffusion tensor imaging showed abnormal pontocerebellar fibers, which might have been caused by cerebellar dysfunction in our patient. A combination of TMS and DTI was also used to determine the pathophysiology of this disease.

Diagnostic usefulness of high resolution cross sectional MRI in symptomatic middle cerabral arterial dissection.

Dissection of the middle cerebral artery (MCA) is less frequent compared with dissection of the vertebrobasilar system or carotid artery. Recently, high-resolution cross sectional MR imaging (HRMRI) has emerged as a potential technique for atherosclerotic plaque imaging in MCA. We introduce the findings of HRMRI in a 56-year-old woman with traumatic MCA dissection. HRMRI showed an intimal flap and tapered pseudolumen with intraluminal hemorrhage. We performed stent deployment about MCA dissection after failed medical treatment. Three months later, there was no in-stent restenosis and no further neurological deficit were noted.

Upbeat nystagmus changes to downbeat nystagmus with upward gaze in a patient with Wernicke's encephalopathy.

We describe a patient with Wernicke's encephalopathy who showed spontaneous upbeat nystagmus with decelerating slow phases that changed to downbeat nystagmus during upward gaze and increased during downward gaze. He also showed horizontal gaze-evoked nystagmus and impaired upward smooth pursuit. Magnetic resonance imaging demonstrated symmetric lesions involving the bilateral medial thalami, periaqueductal gray matters and inferior cerebellar peduncles. In this patient, the decelerating slow phases and disobedience to Alexander's law of upbeat nystagmus suggest both deficient (leaky) and unstable neural integrators subserving vertical eye motion. Dysfunction of the interstitial nucleus of Cajal or its descending pathway to the vestibulocerebellum via the paramedian tract cell groups may be responsible for the upbeat nystagmus and its modulation by gazes in our patient with Wernicke's encephalopathy.

Polyurethane-covered self-expandable nitinol stent for malignant biliary obstruction: preliminary results.

PURPOSE: To evaluate the immediate and long-term results in ten patients with malignant biliary obstruction using a polyurethane-covered, self-expandable nitinol stent. METHODS: A nitinol stent, fully covered with high-elasticity polyurethane, with an unconstrained diameter of 10 mm and a total length of 60-80 mm, was placed transhepatically under fluoroscopic guidance in ten patients. The length of the biliary obstruction varied between 30-50 mm. The follow-up examination included a clinical assessment, serum bilirubin measurement, and ultrasound examinations at one-month intervals in all patients. RESULTS: Initial stent deployment was successful in eight patients. Two patients experienced proximal migration, which was solved by insertion of two, uncovered Wallstents. One patient had the stent removed after two weeks because of severe nausea and vomiting. One patient had delayed migration of the covered stent after 40 weeks. The follow-up duration was 3-40 weeks (Mean: 16.9 weeks). Seven patients died (3-26 weeks) and three patients survived (24-40 weeks). The bilirubin measurements in all patients had significantly decreased one week after stent insertion. The levels of amylase and lipase had did not increase after stent insertion. CONCLUSIONS: A polyurethane-covered, self-expandable nitinol stent can be used effectively and safely in the treatment of malignant biliary obstruction. The preliminary results are favorable, but there is a need for further large studies to determine both long-term survival and patency.