Christopher R. Newey

Addition of Hyperacute MRI Aids in Patient Selection, Decreasing the Use of Endovascular Stroke Therapy

Background and Purpose— The failure of recent trials to show the effectiveness of acute endovascular stroke therapy (EST) may be because of inadequate patient selection. We implemented a protocol to perform pretreatment MRI on patients with large-vessel occlusion eligible for EST to aid in patient selection. Methods— We retrospectively identified patients with large-vessel occlusion considered for EST from January 2008 to August 2012. Patients before April 30, 2010, were selected based on computed tomography/computed tomography angiography (prehyperacute protocol), whereas patients on or after April 30, 2010, were selected based on computed tomography/computed tomography angiography and MRI (hyperacute MRI protocol). Demographic, clinical features, and outcomes were collected. Univariate and multivariate analyses were performed. Results— We identified 267 patients: 88 patients in prehyperacute MRI period and 179 in hyperacute MRI period. Fewer patients evaluated in the hyperacute MRI period received EST (85 of 88, 96.6% versus 92 of 179, 51.7%; P<0.05). The hyperacute-MRI group had a more favorable outcome of a modified Rankin scale 0 to 2 at 30 days as a group (6 of 66, 9.1% versus 33 of 140, 23.6%; P=0.01), and when taken for EST (6 of 63, 9.5% versus 17 of 71, 23.9%; P=0.03). On adjusted multivariate analysis, the EST in the hyperacute MRI period was associated with a more favorable outcome (odds ratio, 3.4; 95% confidence interval, 1.1–10.6; P=0.03) and reduced mortality rate (odds ratio, 0.16; 95% confidence interval, 0.03–0.37; P<0.001). Conclusions— Implementation of hyperacute MRI protocol decreases the number of endovascular stroke interventions by half. Further investigation of MRI use for patient selection is warranted.

Optimizing SPECT SISCOM analysis to localize seizure‐onset zone by using varying z scores

Subtraction ictal single photon emission computed tomography (SPECT) co‐registered to magnetic resonance imaging (MRI) (SISCOM) is a useful modality to identify epileptogenic focus. Using this technique, several studies have generally considered the area of highest ictal hyperperfusion, as outlined by thresholding the difference images with a standard z score of 2, to be highly concordant to the epileptogenic focus. In clinical practice, several factors influence ictal hyperperfusion and using different SISCOM thresholds can be helpful. We aimed to systematically evaluate the localizing value of various z scores (1, 1.5, 2, and 2.5) in a seizure‐free cohort following resective epilepsy surgery, and to examine the localizing information of perfusion patterns observed at each z score.

Variability in Diagnosing Creutzfeldt–Jakob Disease Using Standard and Proposed Diagnostic Criteria

Creutzfeldt‐Jakob disease (CJD) is a rapidly progressive dementia with a median survival of 2‐14 months. The diagnosis can only be made accurately by biopsy/autopsy. However, this is not always feasible or desirable. Thus, diagnostic criteria have been proposed by UCSF, European MRI‐CJD Consortium, and WHO. We will compare these criteria.

Fulminant cerebral demyelination in neuromyelitis optica

A 43-year-old woman with a 2-year history of neuromyelitis optica (NMO; typical imaging [figure 1] and …

Radiological Correlate of Ocular Flutter in a Case with Paraneoplastic Encephalitis

We present an interesting [18F]fluoro‐2‐deoxyglucose positron emission tomography (FDG‐PET) imaging finding in a patient with ocular flutter and cerebellar ataxia as part of anti‐Ma 1/2 antibody‐mediated paraneoplastic syndrome associated with a testicular seminoma. He had a typical anterior mesial temporal hyperintensity on magnetic resonance imaging (MRI) without gadolinium enhancement. In addition, his FDG‐PET images showed increased deep cerebellar and inferior rectus and superior oblique ocular muscles FDG uptake. This case is the first to visualize in vivo the possible underlying neuropathological mechanism of ocular flutter associated with cerebellar nuclei on functional imaging.

Electrographic Features of Lateralized Periodic Discharges Stratify Risk in the Interictal–Ictal Continuum

Purpose: To risk-stratify electrographic features of lateralized periodic discharges (LPDs) in acute structural brain lesions for predictors of electrographic seizures. Methods: This is a retrospective review of 100 consecutive patients with LPDs. Epileptiform features of LPDs were described based on electrographic features: blunt delta morphology, sharply contoured, overlying fast frequencies, and/or rhythmicity (loss of interdischarge interval lasting ≥1 second). EEG seizures were defined as evolving in frequency, distribution, or morphology at ≥2 Hz for ≥10 seconds. Results: Overall, electrographic seizures occurred in 55% of patients with LPDs. Lateralized periodic discharges with rhythmicity (odds ratio 13.91) were most significant for predicting status epilepticus and/or seizures. This was followed by LPDs with overlying faster frequencies (odds ratio 5.16) and then sharply contoured morphology (odds ratio 4.09). Blunt delta morphology (0.24) had the lowest risk for seizures. Conclusions: Electrographic features of LPDs may help determine seizure risk in patients with acute structural lesions. Sharply contoured morphology, overlying fast frequencies, or rhythmicity, showed progressively higher risk of seizures on continuous electroencephalography, whereas blunt delta morphology had the lowest risk of seizures.

Patient With Voltage-Gated Potassium-Channel (VGKC) Limbic Encephalitis Found to Have Creutzfeldt-Jakob Disease (CJD) at Autopsy

To the Editor: Key differential diagnoses of patients presenting with rapidly-progressive dementia include autoimmune encephalitis, such as antibodies to the voltage-gated potassium channel (VGKC), and Creutzfeldt-Jakob disease (CJD). Correct and timely diagnosis of the etiology is paramount, given the catastrophic progression of CJD and the potential for response to immunomodulatory therapy in autoimmune encephalitis. The antemortem diagnosis of rapidly-progressive dementia is predominantly clinical. For example, CJD has established diagnostic criteria that include clinical examination, characteristic findings on electroencephalography (EEG) and brain magnetic resonance imaging (MRI), and cerebrospinal fluid (CSF) 14–32 3. This is in contrast to VGKC limbic encephalitis, which does not have established diagnostic criteria. VGKC typically presents with confusion, seizures, psychosis, and hyponatremia. An underlying cancer has been identified in 47% of patients with VGKC. CJD has been previously promoted as being a mimic of VGKC limbic encephalitis. However, the significance of VGKC antibodies in patients with strong clinical, serologic, and/or imaging evidence of CJD is uncertain. We present a patient with rapidly-progressive dementia who was positive for the VGKC antibody, but with histopathological diagnosis of prion disease at autopsy.

Teaching NeuroImages: Treatment-resistant rapidly progressive amyloid β–related angiitis

A 76-year-old woman presented with 1 month of progressive aphasia, headache, and subsequent right hemiparesis. Initial brain MRI showed a punctate infarct (figure 1, A and C). Susceptibility-weighted imaging was unremarkable. A repeat study 16 days later demonstrated bihemispheric infarcts with multifocal attenuation of intracranial vessels on magnetic resonance angiography (figure 1, B and D). CSF showed a lymphocytic pleocytosis (101 leukocytes/µL) and elevated protein (480 mg/dL). Brain biopsy showed granulomatous angiitis with amyloid deposition and fibrinoid necrosis surrounded by inflammatory cells (figure 2). She rapidly deteriorated on immunosuppression with high-dose IV steroids and has not improved despite a combination of oral steroids and monthly cyclophosphamide.

Two Cases of Serotonin Syndrome with Venlafaxine and Calcineurin Inhibitors

Serotonin syndrome is a potentially life-threatening condition described in all age groups. The diagnosis is clinically determined by either the Sternbach or the Hunter criteria. These criteria are based on recent serotonergic agent use and physical examination findings, including tremor, hyperreflexia, myoclonus, muscle rigidity, diaphoresis, nystagmus, or hyperthermia. The syndrome is an adverse reaction in which a drug is used alone or in combination with another drug resulting in increased centrally available serotonin. One such drug that has been shown to cause serotonin syndrome is the serotonergic-noradrenergic receptor reuptake inhibitor (SNRI) venlafaxine, which is commonly used for major depressive disorder (MDD). We report in this article serotonin syndrome caused by the combination of venlafaxine with a calcineurin inhibitor in two cases of transplant patients diagnosed with MDD. One patient was immunosuppressed with tacrolimus while the other was immunosuppressed with cyclosporine.

Teaching NeuroImages: Wernicke encephalopathy Diagnostically deceptive but treatable

A 54-year-old woman with 4 months of vomiting after gastric fundoplication presented with confusion, generalized weakness, anterograde amnesia, and ophthalmoplegia. Brain MRI showed hyperintensity in the posteromedial thalami (figure, A) and periaqueductal area (figure, B). Serum thiamine was 22 nmol/L (normal 70–180 nmol/L). Supplementation resulted in rapid improvement of ophthalmoplegia but slow improvement of confusion. Anterograde amnesia persisted despite 2 weeks of supplementation.