Bilateral Parieto-occipital Lobes Research Articles

Implications of depressive mood in OSAHS patients: insights from event-related potential

BackgroundObstructive sleep apnea-hypopnea syndrome (OSAHS) is a chronic breathing disorder characterized by recurrent upper airway obstruction during sleep. Although previous studies have shown a link between OSAHS and depressive mood, the neurobiological mechanisms underlying mood disorders in OSAHS patients remain poorly understood. This study aims to investigate the emotion processing mechanism in OSAHS patients with depressive mood using event-related potentials (ERPs).MethodsSeventy-four OSAHS patients were divided into the depressive mood and non-depressive mood groups according to their Self-rating Depression Scale (SDS) scores. Patients underwent overnight polysomnography and completed various cognitive and emotional questionnaires. The patients were shown facial images displaying positive, neutral, and negative emotions and tasked to identify the emotion category, while their visual evoked potential was simultaneously recorded.ResultsThe two groups did not differ significantly in age, BMI, and years of education, but showed significant differences in their slow wave sleep ratio (P = 0.039), ESS (P = 0.006), MMSE (P < 0.001), and MOCA scores (P = 0.043). No significant difference was found in accuracy and response time on emotional face recognition between the two groups. N170 latency in the depressive group was significantly longer than the non-depressive group (P = 0.014 and 0.007) at the bilateral parieto-occipital lobe, while no significant difference in N170 amplitude was found. No significant difference in P300 amplitude or latency between the two groups. Furthermore, N170 amplitude at PO7 was positively correlated with the arousal index and negatively with MOCA scores (both P < 0.01).ConclusionOSAHS patients with depressive mood exhibit increased N170 latency and impaired facial emotion recognition ability. Special attention towards the depressive mood among OSAHS patients is warranted for its implications for patient care.

Stereoelectroencephalography in the setting of a previously implanted responsive neural stimulation device: illustrative case

BACKGROUND Responsive neural stimulation (RNS) is a relatively novel procedure for drug-resistant epilepsy, which involves implantation of a device into the skull and brain. As more devices are implanted, there may be an increasing need to perform intracranial electrocorticography in implant patients with persistent seizures. Given the device location, imaging difficulties with implanted devices, and other technical hurdles, stereoelectroencephalography (SEEG) could be especially challenging. The authors describe the first reported SEEG investigation in a patient with an RNS device, highlighting the technical challenges and clinical data ascertained. OBSERVATIONS A 41-year-old male with drug-resistant epilepsy presented several years after a local surgeon had placed an RNS device with two electrodes in the bilateral parieto-occipital lobes. Because of inadequate seizure control, the patient was offered a repeat SEEG investigation to characterize his epilepsy better. Although more technically challenging than a traditional SEEG implantation, the SEEG investigation was successfully performed, which led to a confirmation of bilateral hippocampal seizure onset. The patient underwent repositioning of his RNS leads with a significant decrease in his seizure frequency. LESSONS Concurrent implantation of SEEG electrodes in a functioning RNS device can be safely performed and can augment our understanding of a patient’s seizures.

Posterior Reversible Encephalopathy Syndrome: A Rare Side Effect of Nivolumab

Introduction: Posterior reversible encephalopathy syndrome (PRES) is a novel clinico-radiological syndrome which is characterized by variable symptoms including visual disturbances, headache, vomiting, seizures and altered consciousness, usually accompanied by hypertension. Several cases of immunotherapy-related PRES have been reported as a rare cause of PRES. We present a case of a 52-year-old male who was started on the immunotherapy nivolumab for his esophageal cancer. He came to the hospital with progressive vision loss and was diagnosed with PRES along with optic neuritis. Case Presentation: A 52-year-old male with no significant past medical history presented to the hospital with left sided numbness and spatial recognition issues. A computed tomography (CT) of the head revealed a 3 cm right parietal mass with vasogenic edema later confirmed with a magnetic resonance imaging (MRI) of the brain. He was started on steroids along with 500 mg Keppra twice a day. CT of the chest, abdomen, and pelvis showed multiple hepatic masses and retroperitoneal lymphadenopathy. He had a colonoscopy about a year prior that was unremarkable. He underwent right frontal parietal craniotomy for single brain metastatic lesion. The biopsy of both the brain and liver mass revealed metastatic adenocarcinoma. He was discharged and started on Fluorouracil, Folinic Acid, Oxaliplatin (FOLFOX) chemotherapy as outpatient for possible upper gastrointestinal (GI) cancer. After two cycles of chemotherapy, a positron emission tomography (PET) scan revealed suspected primary esophageal cancer. Though patient had zero PDL-1 biomarker, nivolumab was added to cycle 3 of FOLFOX with the expectation of having a better response early in the disease. He continued to have stereotactic radiosurgery (SRS) along with steroid taper for local control of brain metastasis. Nivolumab was held after cycle 2 as he developed mild headache, fever and elevated lipases. He was found to be hypertensive to 144/85 mmHg. MRI brain showed improving post-surgical changes. On improvement of symptoms, Nivolumab was reintroduced to cycle 6 of FOLFOX. Unfortunately, a week later he developed progressive vision loss more on right eye. He was sent to optometrist who referred patient to emergency room (ER) because of concern for bilateral papilledema. On admission to ER, he was hypertensive to 182/104 and tachycardic to 107 beats per minute. Physical exam was significant for left inferior quadrantanopia more prominent in right eye. CT head was unrevealing for any infarct. MRI of the orbit and brain showed increased patchy T 2 signal in bilateral parieto-occipital lobes without enhancement suggestive of posterior reversible encephalopathy syndrome (PRES) along with right optic neuritis. These findings were attributed to the immunotherapy nivolumab. He was started on a high dose of prednisone, 1mg/kg/day along with 20 mg lisinopril for strict blood pressure control with a goal of 120/80 mmHg. He was discharged with tapering steroids dose and his symptoms improved within 1 week of treatment. Discussion: Posterior reversible encephalopathy syndrome is a clinico-radiological diagnosis. The underlying pathophysiology involves hypertension and endothelial dysfunction. Hypertension leads to cerebral hyper-perfusion which may cause vascular damage and vasogenic edema leading to blood brain barrier dysfunction. The posterior circulation is the most susceptible to blood pressure changes, thus it is the most common imaging abnormality. PRES frequently develops in the context of cytotoxic medication, immunotherapy, (pre)eclampsia, sepsis, renal disease or autoimmune disorders. MRI is an important diagnostic tool and displays hyperintense lesions in T2-weighted or FLAIR sequences in the parietal-occipital lobes in about 70% of cases but other parts can also be involved. Electroencephalogram (EEG) and lumbar puncture (LP) can be done to rule out other causes. Differentiation is important from an ischemic event as management is different in both cases. Treatment of PRES is symptomatic. Recommendations are to avoid fluctuations in blood pressure with a goal of 130-150/80-100mmHg. If any triggering factor or condition is identified like immunotherapy, it should be avoided or treated accordingly. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Dynamic analysis of CSF1R-related leukoencephalopathy on magnetic resonance imaging: a case report

BackgroundColony-stimulating factor 1 receptor (CSF1R)-related leukoencephalopathy is a rare and rapidly progressive leukoencephalopathy characterized by cognitive, motor, and neuropsychiatric symptoms, which is often misdiagnosed. Magnetic resonance imaging (MRI) signs and follow-up MRI of CSF1R-related leukoencephalopathy could help in establishing a diagnosis, but these features are not widely known by general neurologists.Case presentationA 34-year-old man was admitted for progressive weakness of the right limbs over 8 months. His father and sister had a similar clinical evolution. The primary neurological signs were hemiplegia, cognitive decline, dysarthria, pyramidal signs, ataxia and parkinsonism, and rapid disease progression. Cerebrospinal fluid analysis results were normal. Despite receiving treatment for improving cerebral metabolism and relieving the muscle spasm, his symptoms did not improve significantly. Brain MRI showed lesions concentrated in the corpus callosum and the deep white matter of the bilateral parieto-occipital lobes, periventricular areas, and corticospinal tracts. There was an enhanced lesion after a gadolinium-enhanced MRI scan. Over the 8-month progression, the lesions always exhibited restricted diffusion. The diffuse lesions gradually increased as the disease progressed. Genetic sequencing results showed a novel heterozygous missense mutation (c.2267 T > C p.L756P) in the CSF1R gene. The patient was treated with citicoline and idebenone for 4 days to improve cerebral metabolism, but his symptoms did not improve significantly.ConclusionThe multiple lesions involving the pyramidal tract and white matter showed continuously restricted diffusion on brain imaging and gradually increased with disease progression.

Optic Nerve Infarction in a Patient With Coronavirus Disease 2019.

Severe acute respiratory syndrome 2 (SARS-CoV2), also called coronavirus disease 2019 (COVID-19), has spread worldwide and affected millions of lives. Although there are many unaddressed questions about the pathogenesis of the virus and the best treatment, it is known that the virus affects several organ systems, including respiratory, gastrointestinal, and neurologic (1–4). Neurologic manifestations reported in COVID-19 patients include headache, anosmia, seizure, stroke, encephalitis, and Guillain–Barre syndrome (4); However, neuro-ophthalmic manifestations have infrequently been reported (5–8). We describe a patient with COVID-19 who developed thrombosis of the left internal carotid artery leading to infarction of the left optic nerve. A 50-year-old man was found to have a positive polymerase chain reaction (PCR) test for COVID-19. Twelve days later, he developed fever, cough, and dyspnea. His respiratory symptoms worsened, and 2 days later, he was admitted to hospital for acute onset of aphasia and right hemiparesis. After computed tomography (CT) of the brain excluded a hemorrhagic stroke, the patient was given intravenous tissue plasminogen activator and referred to our medical center. His medical history included poorly controlled diabetes mellitus, hypertension, and hyperlipidemia. On admission, the patient was lethargic, oriented to self, aphasic, and not following commands. He had right hemiplegia and left gaze preference. Nasal and oropharyngeal swabs for real-time PCR confirmed infection with SARS-CoV2, and due to his respiratory failure, he was intubated and transferred to the intensive care unit. His hematologic studies included white blood cells of 12.6 × 103/µL (normal, 4–11/µL) with 4% lymphocyte (normal, 15%–52%), C-reactive protein 214 mg/L (normal, 0–10.9 mg/L), d-dimer >20,000 ng/mL (normal, 0–240 ng/mL), lactate dehydrogenase 280 U/L (normal, 120–240 U/L), and fibrinogen 1,228 mg/dL (normal, 220–498 mg/dL). Neuroimaging studies were obtained. CT angiography (CTA) was consistent with occlusion of the cervical and intracranial portion of the left internal carotid artery (Fig. 1). Subsequent brain MRI demonstrated scattered acute infarcts in the distribution of the left middle cerebral artery. Diffusion-weighted imaging (DWI) showed restricted diffusion along the intraorbital portion of the left optic nerve (Fig. 2).FIG. 1.: CTA. Sagittal and axial images reveal total occlusion of the left internal carotid artery (A, arrow) and absent flow in the artery at the skull base (B, arrow).FIG. 2.: A. Diffusion-weighted scan shows multiple areas of ischemia in the left cerebral hemisphere. B. Diffusion-weighted scan demonstrates restricted diffusion in the left intraorbital optic nerve (arrow). C. The apparent diffusion coefficient (ADC) map confirms restricted diffusion of the left optic nerve (arrow).After 3 weeks, as the patient's respiratory condition and mental status improved, he reported loss of vision in his left eye. At that time, visual acuity was 20/50 in the right eye and no light perception in the left eye. There was a left relative afferent pupillary defect, eye movements were intact, and the fundi were unremarkable. Six weeks later, visual function was unchanged, but the left optic disc was now pale. Cerebrovascular ischemia is a recognized complication of the COVID-19. A series of 219 patients with COVID-19 from Wuhan, China, revealed a 4.6% rate for acute ischemic stroke (1). In this series, patients with COVID-19 who developed stroke were significantly older than non-COVID-19 stroke patients (75.7 ± 10.8 vs 52.1 ± 15.3 years) and had other cardiovascular risk factors. In contrast, Oxley et al (2) reported 5 patients younger than 50 years with COVID-19 who were diagnosed with acute stroke; 2 had no cardiovascular risk factors. Our patient had several risk factors for stroke, including diabetes mellitus, hypertension, and hypercholesterolemia. The mechanism of thromboembolic events in COVID-19 is controversial. Connor and colleagues (3) suggested that a contributing factor is the elevated level of coagulative factors, including platelet, fibrinogen, and d-dimer. Vascular endothelial dysfunction that impairs its antithrombotic properties is another proposed mechanism (4). There are few reports of visual loss associated with COVID-19 disease. Four patients have been documented with profound visual loss due to bilateral parieto-occipital or bilateral occipital lobe infarctions (5–7). In addition, Zhou et al (8) described a patient with COVID-19 who developed bilateral myelin oligodendrocyte glycoprotein (MOG)–associated optic neuritis. The authors speculated that COVID-19 provided a “potential connection” between the viral disease and central nervous system demyelination. DWI in our patient demonstrated acute infarction of the intraorbital portion of the left optic nerve due to thrombosis of the left internal carotid artery. Our report expands the spectrum of neuro-ophthalmic findings in patients with COVID-19.

Cerebral Vasculitis in a Case of Henoch–Schönlein Purpura

Background: Henoch–Schönlein purpura (HSP) is the most common vasculitis seen in children that rarely involve central nervous system (CNS) (0.65%–8%). Patients with CNS vasculitis may present with symptoms such as headache, seizures, focal neurological deficit, or behavior abnormalities. We describe a case of HSP where the patient presented with developmental delay along with skin rash and renal involvement. Clinical Description: A 15-month-old boy presented with a history of developmental delay and skin rashes for the past 2 months. There was no significant antenatal or birth history. At the age of 15 months, the child could not sit without support, could not transfer objects from one hand to other, could only speak bisyllables, and could not wave “bye-bye.” On examination, the patient had normal vitals with equal volume peripheral pulses and normal blood pressure in all four limbs. Urine examination showed microscopic hematuria, and kidney functions were mildly deranged. Skin biopsy showed immunoglobulin A vasculitis. Magnetic resonance imaging brain was done which revealed multifocal areas of altered signal intensity in periventricular deep white matter in bilateral frontal and parieto-occipital lobes, appearing hyperintense on T2-weighted and fluid-attenuated inversion recovery sequences, showing evidence of diffusion restriction, suggestive of areas of acute ischemia. The findings were consistent with manifestations of CNS vasculitis. Management: The patient was managed conservatively and advised physiotherapy and follow-up for developmental delay. Conclusion: HSP can rarely involve CNS, however, developmental delay in HSP has never been reported before.

Posterior reversible encephalopathy syndrome in a patient with diabetic ketonuria

Posterior reversible encephalopathy syndrome is a condition presenting with non-specific symptoms like nausea, vomiting and headache along with neurological manifestations like altered mental status, seizure, visual impairment and even coma. These symptoms are coupled with characteristic radiological findings of vasogenic edema in the bilateral parieto-occipital lobe which is usually reversible. We present here, a young 30 years old male, with dizziness, vomiting, generalized weakness, altered mental status with cortical blindness and focal and generalized tonic-clonic seizures in the background of first presentation of type 2 diabetes mellitus with ketonuria. Characteristic findings in Magnetic Resonance Imaging and reversal of the symptoms helped to reach the diagnosis of posterior reversible encephalopathy syndrome in our patient. The patient was discharged in stable condition after reversal of the symptoms and treatment of type 2 diabetes mellitus.

Effects of short-term deep brain stimulation in subthalamic nucleus on glucose metabolism in Parkinson′s disease

Objective To study the effect of short-term treatment of subthalamic nucleus (STN) deep brain stimulation (DBS) on cerebral glucose metabolism in patients with Parkinson′s disease (PD) and its relationship with the change of brain motor-related nerve pathways. Methods Five patients (2 males, 3 females; age: (63.6±11.8) years) with PD who underwent STN DBS between January 2014 and December 2018 were enrolled in this study. All patients underwent 18F-fluorodeoxyglucose (FDG) PET in DBS-off state before and 3 months after operation. Quantitative expression of PD-related metabolic pattern (PDRP) were calculated by scaled subprofile model/principal component analysis (SSM/PCA) on PET images. Brain regions with changes of glucose metabolism after DBS were located by statistical parametric mapping (SPM) paired t test. Results Compared with pre-operation, PDRP expression (5.1±1.3 vs 2.9±1.8) and unified Parkinson′s disease rating scale (UPDRS) motor score (50.2±8.2 vs 28.0±5.4) of PD patients were significantly decreased 3 months after STN DBS (t values: 6.17 and 3.88, both P<0.05). After DBS, the glucose metabolism of bilateral globus pallidus/putamen, caudate nucleus, thalamus, insula, pons and cerebellum decreased, while the glucose metabolism of bilateral prefrontal motor area and parietooccipital lobe increased (t=3.75, P<0.01). Conclusions Short-term STN DBS therapy can inhibit the cortico-striatum-pallidum-hypothalamus-cortex motor loop, which is abnormally excitable in the brain of PD. PDRP, as an imaging characterization of the regulation of this loop, is expected to become an imaging marker for monitoring the treatment of PD. Key words: Parkinson disease; Deep brain stimulation; Subthalamic nucleus; Positron-emission tomography; Deoxyglucose

Evaluation of different ulegyria patterns with magnetic resonance imaging

Ulegyria is a parenchymal sequel of hypoxic ischemic encephalopathy causing mushroom-like appearance in gyri. Aim of the present study was to evaluate clinico-radiological findings of patients who applied with different clinical features, predominantly epilepsy, and who were found to have ulegyria formations in MRI examinations. The study included a total of 30 patients (12 female and 18 male) who applied with different types of seizures in February 2011–August 2016 period and had brain MRI examinations using 1.5T MRI scanner. Mushroom-shaped gyri accompanied by gliosis and atrophy in subcortical white matter were considered ulegyria. Locations, MRI features and accompanying pathologies of ulegyria formations were studied. Age of the patients ranged from 4 to 62 (mean 26.0 ± 13.8). Both cerebral lobes were involved in 18 patients. In terms of involved area, symmetrical or asymmetrical involvements were observed in occipital lobes in 26 patients, parietal lobes in 19, frontal lobes in 12 and temporal lobes in 4. The most common involvement type was bilateral occipital and bilateral parieto-occipital lobe involvements with five patients each. Lesions were symmetrical in 11 patients. Six patients had cingulate gyrus atrophy. Nineteen patients had different levels of symmetrical or asymmetrical ventricular dilatation. Cranial asymmetry was observed in six patients with unilateral involvement and in one patient with generalized involvement. Although ulegyria predominantly involves parasagittal watershed areas in MRI examinations of patients applying with epilepsy, clinical manifestations and appearance of lesions could vary depending upon the size of involved area and level of injury.

Postpartum Woman With Seizures

A 27-year-old woman, postpartum day 9, presented with sudden onset of headache, vomiting, visual blurring, and 3 episodes of generalized tonic-clonic seizures. She had had an uneventful cesarean delivery 9 days previously and was discharged home. Her antenatal period was uneventful, and she did not have gestational hypertension. On examination, she was alert, oriented, and afebrile. Her blood pressure was 150/100 mm Hg, which had increased from her mean antenatal recording of 130/80 mm Hg. Fundus examination result was normal, and there were no focal neurologic deficits. Magnetic resonance imaging (MRI) of the brain showed T2 and T2 fluid-attenuated inversion recovery (FLAIR) hyperintense signals in bilateral parietooccipital lobes (Figures 1 and 2) and bilateral cerebellar hemispheres (Figure 3), without any diffusion restriction. She was treated with intravenous labetalol, nifedipine, and fosphenytoin. Her blood pressure normalized and her symptoms subsided, and she was later discharged.Figure 2Axial MRI showing T2 FLAIR hyperintensity of bilateral parietal lobes (arrows).View Large Image Figure ViewerDownload Hi-res image Download (PPT)Figure 3Axial MRI showing T2 FLAIR hyperintensity of bilateral cerebellar hemispheres (arrows).View Large Image Figure ViewerDownload Hi-res image Download (PPT) Posterior reversible encephalopathy syndrome. Posterior reversible encephalopathy syndrome is a clinicoradiologic entity, characterized by the clinical triad of headache, visual blurring, and seizures. The classic neuroimaging feature is parietooccipital lobe edema, observed as T2 hyperintense lesions in the MRI.1Bartynski W.S. Posterior reversible encephalopathy syndrome, part 1: fundamental imaging and clinical features.AJNR Am J Neuroradiol. 2008; 29: 1036-1042Crossref PubMed Scopus (796) Google Scholar Cerebellar involvement as observed in this case is much rarer, and such atypical presentations are also possible.2McKinney A.M. Short J. Truwit C.L. et al.Posterior reversible encephalopathy syndrome: incidence of atypical regions of involvement and imaging findings.AJR Am J Roentgenol. 2007; 189: 904-912Crossref PubMed Scopus (519) Google Scholar Posterior reversible encephalopathy syndrome is usually accompanied by hypertension. Other causes include chronic kidney disease and immunosuppressive therapy.3Garg R.K. Posterior leukoencephalopathy syndrome.Postgrad Med J. 2001; 77: 24-28Crossref PubMed Scopus (236) Google Scholar Patients with blood pressure fluctuations in the antepartum and postpartum period are particularly vulnerable for the syndrome. In the setting of postpartum seizures, the differential diagnosis includes postpartum eclampsia, cerebral venous thrombosis, and intracerebral hemorrhage.

Recurrent posterior reversible encephalopathy syndrome in nephrotic syndrome: case report and review of the literature

Sequential neuroimaging before and after seizures has not been reported in patients with nephrotic syndrome and recurrent posterior reversible encephalopathy syndrome (PRES). We report a 13-year-old nephrotic female patient with recurrent PRES during and after cessation of cyclosporine A (CyA). She had headache, visual disturbance and acute hypertension, followed by seizures. The brain magnetic resonance imaging (MRI) before seizures revealed a high signal intensity area on fluid-attenuated inversion recovery and diffusion-weighted images and a low signal intensity area on T1-weighted images in bilateral parieto-occipital and left temporal lobes. Cessation of CyA resulted in clinical improvement. The follow-up MRI 2 months after the initial episode showed a complete resolution. Six months later, she had similar symptoms, edema, severe hypoalbuminemia, renal insufficiency, and acute pancreatitis before seizures. The brain MRI after seizures showed similar abnormalities in the same regions, which completely resolved 2 months later. Recurrence of acute severe hypertension, nephrotic state (edema/ hypoalbuminemia), and renal insufficiency may lead to recurrent PRES and thus early treatment of trigger factors, especially of hypertension, is important to reduce the episodes of PRES.

Neural strategies for reading Japanese and Chinese sentences: A cross-linguistic fMRI study of character-decoding and morphosyntax

Japanese and Chinese share virtually identical morphographic characters invented in ancient China. Whereas modern Chinese retained the original morphographic functionality of these characters (hanzi), modern Japanese utilizes these characters (kanji) as complex syllabograms. This divergence provides a unique opportunity to systematically investigate brain strategies for sentence reading in Japanese–Chinese bi-literates. Accordingly, we investigated brain activation associated with Japanese and Chinese reading in 14 native Japanese speakers literate in Mandarin and 14 native Mandarin speakers literate in Japanese using functional magnetic resonance imaging performed on a 3T system. The activation pattern exhibited clearly distinct features specific for each language. Regardless of the subject’s native language literacy, Chinese reading activated an area significantly larger than Japanese reading, suggesting that brain processes involved in Chinese reading were much more complex than Japanese reading. Significant recruitment of corresponding cortical areas in the right hemisphere with Chinese reading was also apparent. The activation patterns associated with Japanese reading by native Japanese literates was highly consistent with previous reports, and included the left inferior frontal gyrus (IFG), left posterior temporal lobe (PTL), and left ventral premotor cortex (PMv). The activation pattern associated with Chinese reading by native Chinese literates was also highly consistent with previous reports, namely the left IFG, left PTL, left PMv, left anterior temporal lobe (ATL), and bilateral parieto occipital lobes (LPOL). The activation pattern associated with Chinese reading by native Japanese literates was virtually identical to that by native Chinese literates, whereas the activation pattern associated with Japanese reading by native Chinese literates was signified by additional activation of LPOL compared to that by native Japanese literate. The study indicated that IFG and PTL are universal language areas, while PMv is the area for decoding complex syllabograms. LPOL is the “Chinese language area,” while ATL is essential for languages with analytic morphosyntax.

A rare entity in ED: posterior reversible encephalopathy syndrome

Posterior reversible encephalopathy syndrome is a clinico-neuroradiologic entity with typical symptoms and symmetric high-signal intensity lesions in the bilateral parietooccipital lobes on T2-weighted or fluid-attenuated inversion recovery magnetic resonance imaging. In this presentation, we report a case of posterior reversible encephalopathy syndrome who was admitted to our emergency department because of seizure and deterioration of consciousness. The aim of this presentation is to alert the emergency physicians about one of the hypertensive emergencies with neurologic symptoms associated with hypertension.

A case of cerebral amyloid angiopathy with reversible white matter lesions and multiple cerebral microbleeds

A 59-year-old woman presented with a 7-year history of headache. She showed no neurological abnormality. T(2) weighted magnetic resonance (MR) images showed a hyperintense signal in the white matter in the bilateral parieto-occipital lobe without abnormal enhancement. A small amount of prednisolone was administered for rheumatoid arthritis. After prednisolone was discontinued, the T(2) weighted images showed an expansion of the hyperintense signal lesions seen in the white matter, and T(2) weighted image showed multiple foci of petechial bleeding in the cortex and subcortex of the bilateral occipital lobe. A brain biopsy specimen from the right occipital lobe revealed deposition of amyloid in the subarachnoidal and cortical vessel walls and transmural infiltration of a few lymphocytes, eosinophils, and giant histiocytes. Subsequently the patient was diagnosed with central nervous system vasculitis associated with cerebral amyloid angiopathy (CAA). After 5 months, the T(2) weighted images showed a remarkable regression of the hyperintense signal lesions in the white matter of the bilateral parieto-occipital lobe without the administration of any maintenance immunosuppressive agents. However, T(2) weighted image showed an increase of multiple cortico-subcortical foci of petechial bleeding. Her headache did not improve during the illness. Thus, we should consider the diagnosis of CAA when patients present with reversible white matter lesions and multiple cerebral microbleeds simultaneously.

Embryonal tumor with abundant neuropil and true rosettes (ETANTR) with a focal amplification at chromosome 19q13.42 locus: Further evidence of two new instances in China

Recently, the term "embryonal tumor with multilayered rosettes" (ETMR), including embryonal tumor with abundant neuropil and true rosettes (ETANTR) and ependymoblastoma (EBL) as a distinct tumor entity, has become an important topic of discussion for neuropathologists since the discovery of a unique genomic alteration in 2009. Here, we contribute two new East Asian instances of ETANTR in a 29-month-old boy who underwent subtotal resection of a large tumor in the bilateral parieto-occipital lobes and a 4-year-old boy who underwent subtotal resection of the right midpontine neoplasm. Both tumors showed a typical histopathological pattern of hypercellular clusters of undifferentiated small cells and ependymoblastic rosettes admixed with paucicellular neuropil-like zones indicative for ETANTR. Rare Homer-Wright neuroblastic rosettes and papillary pseudorosettes, as well as enlarged lumina with mucinous material, were also observed. Immunohistological studies revealed that tumor cells in hypercellular and paucicellular zones were diffusely positive for microtubule-associated protein 2; ependymoblastic rosette cells stained with epithelial membrane antigen at the luminal membrane and exhibiting strong immunoreactivity with p53 protein. β-Catenin and Nestin were frequently detected in the hypercellular zones as well as in the ependymoblastic rosettes. Fluorescence in situ hypribization analysis revealed that both cases contained a unique focal amplification at the 19q13.42 chromosome locus and chromosome 2 polysomy. A new WHO classification of tumors of the CNS should be considered for these neoplasms with unique focal amplification at the 19q13.42 chromosome locus, based on the clinicopathological and molecular features of ETANTR that are distinct and reproducibly recognizable.

Altered Processing of Visual Memory in Patients with Mesial Temporal Sclerosis: An fMRI Study

Hippocampal complex and neocortex play distinct, complementary roles in processing of memory, which is impaired in patients with mesial temporal sclerosis (MTS). Ten right-sided MTS patients and 10 controls were prospectively assessed by functional Magnetic Resonance Imaging (fMRI) using encoding and retrieval of visual memory tasks. Image analyses were done using SPM2 and voxels showing activity with T-score>4 were considered significant. Two-sample t-test was applied for equality of means and P<.01 was considered significant. Patterns of activity in both encoding and retrieval tasks were compared between the patients and controls. In normal controls, there was activation of bilateral tail of hippocampus, parahippocampal gyrus, occipital (right>left), right prefrontal, and inferior frontal region (T-score>9) during the encoding of memory and during the retrieval, there was activation of left inferior frontal region, bilateral parahippocampal gyrus, and occipital and parietal region (right>left) activity (T-score>4). In patients there was activation of bilateral prefrontal (left≫right), bilateral inferior parietal lobule (right≫left), and bilateral parieto-occipital lobe activity(T-score>4) during encoding and there was comparatively less activation (T-score>3) of bilateral inferior parietal lobule (left≫right) and bilateral prefrontal (right≫left) regions during retrieval. Visual memory processing is affected and altered in patients with MTS. Reallocation of visual memory processing is observed in patients with MTS suggesting different networking.

Posterior reversible encephalopathy syndrome

Posterior reversible encephalopathy syndrome (PRES) is a clinico-neuroradiological entity with typical symptoms and symmetric high-signal intensity lesions in the bilateral parieto-occipital lobes on T2-weighted or fluid-attenuated inversion recovery (FLAIR) MRI. We described three patients with PRES of varied etiologies. Patient 1 was a young man with severe hypertension who presented with headache and visual disturbance. Patient 2 had leukemia and was receiving umbilical cord blood cell transplantation with immunosuppressant, and developed PRES with convulsions. Patient 3 was a pregnant woman with renal failure, who repeatedly developed PRES with convulsions. FLAIR and apparent diffusion coefficient mapping were useful in detecting PRES lesions in our patients, although diffusion-weighted imaging and CT scans had limited use in the diagnosis. Adequate and prompt treatment with antihypertensive medication immediately ameliorated the symptoms, with improvement of abnormal MRI findings. In previous reports, delayed diagnosis might have affected the prognosis. Further work on the clinical manifestations of PRES and its therapy is required.

Posterior reversible encephalopathy syndrome at term pregnancy

Posterior reversible encephalopathy syndrome (PRES) is a cliniconeuroradiological syndrome associated with various clinical conditions, presenting with headache, encephalopathy, seizures, cortical visual disturbances or blindness. Imaging predominantly shows parieto-occipital white matter changes, with vasogenic oedema being the most accepted pathophysiology. We report a 25-year-old primigravida who presented in term pregnancy with seizures and blindness, scheduled for emergency caesarean section. She was managed peroperatively under general anaesthesia and shifted to intensive care unit. Postoperative computed tomography brain revealed an intra-axial hypodensity involving predominantly white matter regions of bilateral parieto-occipital lobes, right caudate nucleus and right cerebellum, suggestive of PRES. Clinical improvement with complete resolution of visual disturbances was observed with supportive treatment. The importance of prompt suspicion and management in preventing short- and long-term neurological deficits in reversible condition like PRES is highlighted.

Posterior Reversible Encephalopathy Syndrome in severe preeclampsia: case report and literature review

We describe a 23 year old primigravid patient with severe preeclampsia complicated by posterior reversible encephalopathy syndrome (PRES), who presented with sensory and motor deficits and amnesia in the postpartum period Cranial magnetic resonance imaging (MRI) showed abnormal areas in the white matter of bilateral parieto-occipital lobes, indicating brain edema which disappeared completely on the follow-up scan taken four weeks after delivery together with complete symptom regression. The development of PRES in preeclampsia is discussed and the importance of prompt postpartum blood pressure control is emphasized.

Development of a Partial Balint's Syndrome in a Congenitally Deaf Patient Presenting as Pseudo-Aphasia

We present a 56 year-old, right-handed, congenitally deaf female who exhibited a partial Balint's syndrome accompanied by positive visual phenomena restricted to her lower right visual quadrant (e.g., color band, transient unformed visual hallucinations). Balint's syndrome is characterized by a triad of visuo-ocular symptoms that typically occur following bilateral parieto-occipital lobe lesions. These symptoms include the inability to perceive simultaneous events in one's visual field (simultanagnosia), an inability to fixate and follow an object with one's eyes (optic apraxia), and an impairment of target pointing under visual guidance (optic ataxia). Our patient exhibited simultanagnosia, optic ataxia, left visual field neglect, and impairment of all complex visual-spatial tasks, yet demonstrated normal visual acuity, intact visual fields, and an otherwise normal neurocognitive profile. The patient's visuo-ocular symptoms were noticed while she was participating in rehabilitation for a small right pontine stroke. White matter changes involving both occipital lobes had been incidentally noted on the CT scan revealing the pontine infarction. As the patient relied on sign language and reading ability for communication, these visuo-perceptual limitations hindered her ability to interact with others and gave the appearance of aphasia. We discuss the technical challenges of assessing a patient with significant barriers to communication (e.g., the need for a non-standardized approach, a lack of normative data for such special populations), while pointing out the substantial contributions that can be made by going beyond the standard neuropsychological test batteries.