Kumar Das

An effective immunotherapy regimen for VGKC antibody-positive limbic encephalitis

Background Voltage-gated potassium channel antibody-positive limbic encephalitis (VGKC+LE) frequently improves with immunotherapy, although the optimum regimen is unknown. The effectiveness of a combination immunomodulatory regimen was tested in consecutive VGKC+LE patients. Methods This was an open-label prospective study of nine VGKC+LE patients. All patients had plasma exchange (50 ml/kg), intravenous immunoglobulin (2 g/kg) and intravenous methylprednisolone (1 g×3), followed by maintenance oral prednisolone (1 mg/kg/day). Mycophenolate (2 g/day) was used in the first three patients. Assessments included serial clinical, cognitive, brain MRI and VGKC antibody testing. Results Within 1 week, seizures and hyponatraemia remitted in all affected patients. Cognitive function improved in all patients within 3 months. MRI appearances improved substantially within 9 months, with remission of inflammation in the majority of patients. All achieved immunological remission with normal VGKC antibody titres within 1–4 months. Major adverse events of therapy included one septicaemia and one thrombosis on plasma exchange and one death from sepsis after incidental bowel surgery. One patient remains in remission after 40 months of follow up, 26 months after being off all treatment. Conclusions Our immunotherapy regimen was effective for the treatment of the clinical, cognitive and immunological features of VGKC+LE. Radiological improvement was seen in the majority. Pending randomised controlled trials, this regimen is proposed for the treatment of VGKC+LE.

Initial management of hydrocephalus associated with Chiari malformation Type I-syringomyelia complex via endoscopic third ventriculostomy: an outcome analysis

OBJECT The aim of this study was to evaluate the efficacy of endoscopic third ventriculostomy (ETV) in patients with Chiari malformation Type I (CM-I) and hydrocephalus with or without syringomyelia. METHODS The authors identified, in a prospective endoscopy database, 16 adults and children (age range 2-68 years) with CM-I and hydrocephalus that had been managed with ETV. They reviewed the clinical features and radiographic findings for all patients. Fifteen patients underwent ETV as a primary treatment, whereas 1 patient underwent the procedure at the time of shunt failure. All patients had symptomatic hydrocephalus with either aqueductal or fourth ventricular outflow obstruction. The mean duration of follow-up was 42 months. RESULTS Fifteen patients (94%) remain shunt free following ETV for CM-I. Five (83%) of the 6 patients with a syrinx had improvement or resolution of the syrinx following ETV. Six patients (37.5%) underwent foramen magnum decompression for persistent CM-I -- or syrinx-related symptoms. There was no cerebrospinal fluid leakage or intracranial pressure-related problem following foramen magnum decompression. CONCLUSIONS Endoscopic third ventriculostomy provides a durable method of treatment for hydrocephalus associated with CM-I. It is effective as a primary treatment, and the authors advocate its use as a replacement for routine ventriculoperitoneal shunt insertion in these patients. Management of the hydrocephalus alone is often sufficient and may obviate decompression, although a significant proportion of patients will still need both procedures.

Paralytic rabies after a two week holiday in India

Rabies is an acute infection of the central nervous system (CNS) and caused by rabies virus or related members of the genus Lyssavirus , family Rhabdoviridae.1 The virus is usually transmitted through a dog bite and produces one of the most important viral encephalitides worldwide, with at least 40 000 deaths reported annually.2 However, it is rare in the United Kingdom, where just 12 cases have been reported since 19773: 11 were imported from overseas, and one occurred in a bat handler infected in Scotland with European bat lyssavirus type 2a.4 Most UK patients presented with furious rabies, which is characterised by hydrophobia and spasms. We report a case of paralytic rabies in a tourist after a two week holiday in Goa, India. Fig 2 Phylogenetic tree depicting the relation between the rabies virus sequence amplified from our patient (RV1964—boxed) and other viruses originating in Asia. The horizontal branch lengths represent the extent of difference between the strains (expressed as nucleotide substitutions per nucleotide site), and the closer viruses are on the tree, the more closely they are related A woman in her late 30s was admitted to her local general hospital under the orthopaedic surgeons, with lower back pain radiating to the left leg. The pain had started four days earlier, was severe and shooting in nature, and was getting worse. She had been seen twice in casualty in the preceding days, and by the time of admission she was unable to walk. She also had a headache and had vomited once. Three and a half months before admission, during a two week holiday to Goa, India, she had been bitten by a dog; she was walking in the street when a puppy on a lead nipped her on the left leg. There was a slight …

Neuropathic pruritus (itch) in neuromyelitis optica.

Background: Neuropathic pruritus (itch) is an uncommon, but well described, symptom in neurology. There are itch-specific neurons in the dorsal horn of the spinal cord. We noted excessive pruritus in patients with neuromyelitis optica (NMO). Objective: We aimed to explore the characteristics of pruritus in NMO patients. Methods: We reviewed case records of a well-defined cohort of 45 serial aquaporin-4 antibody-positive patients visiting the national NMO service. All patients were interviewed. Results: Of the 45 antibody-positive NMO patients, 44 had myelitis and 12 of those 44 (27.3%) patients reported pruritus within a week of other symptoms of transverse myelitis with central cord involvement. In three patients, pruritus was the first symptom of a relapse, while in one case, pruritus was the very first symptom of the index episode of NMO. Conclusion: Neuropathic pruritus seems to be a common, but under-recognised symptom of myelitis associated with NMO.

An evaluation of the usefulness of neuroimaging for the diagnosis of Japanese encephalitis

Japanese encephalitis virus (JEV) is estimated to cause 30–50,000 cases of encephalitis every year. The disease occurs mainly in rural Asia and is transmitted to humans from birds and pigs by mosquitoes of the genus Culex. JE is diagnosed with antibody testing of the serum and CSF, but this is not available in many hospitals. Neuroimaging abnormalities, particularly thalamic hypodensity on computed tomography (CT) and hyperintensity on T2 weighted magnetic resonance imaging (MRI) have been described in case studies, but their usefulness for diagnosing JE is not known. We have therefore evaluated the usefulness of neuroimaging (CT and MRI) for the diagnosis of JE. The findings of thalamic lesions were compared with the final serological diagnosis in a cohort of 75 patients (children and adults) with suspected CNS infections in Southern Vietnam, a JEV endemic area. Thalamic lesions on CT and/or MRI combined had sensitivity 23% (95% confidence interval 12.9–33.1%), specificity 100%, positive predictive value 100% and negative predictive value 42.1% (95% confidence interval 30.2–53.8%) for a diagnosis of JE in this cohort. Over time, the thalamic lesions resolved in some patients. One patient showed disappearance of lesions on CT followed by reappearance of the lesions some time later, known as the fogging effect. In this setting, the presence of thalamic abnormalities suggested the diagnosis of JE, but their absence did not exclude it.

Somatosensory Change and Pain Relief Induced by Repetitive Transcranial Magnetic Stimulation in Patients With Central Poststroke Pain

To quantify changes in pain and somatosensory function in patients with central poststroke pain (CPSP) syndrome following five sessions of repetitive transcranial magnetic stimulation (rTMS).

The role of magnetic resonance imaging in the management of brain metastases: diagnosis to prognosis

This article reviews the different MRI techniques available for the diagnosis, treatment and monitoring of brain metastases with a focus on applying advanced MR techniques to practical clinical problems. Topics include conventional MRI sequences and contrast agents, functional MR imaging, diffusion weighted MR, MR spectroscopy and perfusion MR. The role of radiographic biomarkers is discussed as well as future directions such as molecular imaging and MR guided high frequency ultrasound.

Overall survival in patients with malignant glioma may be significantly longer with tumors located in deep grey matter

BACKGROUND The aim of this study was to assess the correlation of overall survival with tumor location (lobar vs. deep grey matter) and with other clinical and imaging variables in a cohort of patients with high grade gliomas. METHODS Adult patients with newly diagnosed supratentorial WHO grade 3 and 4 gliomas were evaluated. Clinical data included demographics, symptoms at presentation, treatment variables, and overall survival. Radiological data included tumor side, site (deep vs. lobar) and size, extent of peritumoral edema, and presence of midline shift. Biostatistics were carried out using log rank tests and univariate and multivariate Cox regression models. RESULTS A total of 121 patients were investigated, 23 (19.0%) with WHO grade 3 and 98 (81.0%) with WHO grade 4 gliomas. Tumors had lobar location in 96 cases (79.3%) and deep grey matter location in 25 cases (20.7%). Median survival time for all patients was 26 weeks (IQR: 14-53). Patients with deep tumors survived significantly longer than those with lobar gliomas (log rank test, p=0.0083). Extensive brain edema significantly shortened survival (log rank test, p=0.0003). Presence of midline shift (>1 cm) was a statistically significant risk factor for shorter survival (log rank test, p<0.0001). The univariate Cox regression model demonstrated statistical significance for the variables age, side, site and size of tumor, presence of extensive edema, and presence of mass effect (>1 cm). In the multivariate Cox models, tumor grade, site and size showed statistical significance. CONCLUSIONS This study suggests that patients with deep grey matter gliomas may survive significantly longer after the initial diagnosis than those with tumors in a lobar location. This is a potentially novel finding, which may corroborate the theory of differential invasion of glioma cells in different microenvironments of the brain, but remains to be confirmed in future prospective studies.

Diffusion-weighted MRI characteristics of the cerebral metastasis to brain boundary predicts patient outcomes

BackgroundDiffusion-weighted MRI (DWI) has been used in neurosurgical practice mainly to distinguish cerebral metastases from abscess and glioma. There is evidence from other solid organ cancers and metastases that DWI may be used as a biomarker of prognosis and treatment response. We therefore investigated DWI characteristics of cerebral metastases and their peritumoral region recorded pre-operatively and related these to patient outcomes.MethodsRetrospective analysis of 76 cases operated upon at a single institution with DWI performed pre-operatively at 1.5T. Maps of apparent diffusion coefficient (ADC) were generated using standard protocols. Readings were taken from the tumor, peritumoral region and across the brain-tumor interface. Patient outcomes were overall survival and time to local recurrence.ResultsA minimum ADC greater than 919.4 × 10-6 mm2/s within a metastasis predicted longer overall survival regardless of adjuvant therapies. This was not simply due to differences between the types of primary cancer because the effect was observed even in a subgroup of 36 patients with the same primary, non-small cell lung cancer. The change in diffusion across the tumor border and into peritumoral brain was measured by the “ADC transition coefficient” or ATC and this was more strongly predictive than ADC readings alone. Metastases with a sharp change in diffusion across their border (ATC >0.279) showed shorter overall survival compared to those with a more diffuse edge. The ATC was the only imaging measurement which independently predicted overall survival in multivariate analysis (hazard ratio 0.54, 95% CI 0.3 – 0.97, p = 0.04).ConclusionsDWI demonstrates changes in the tumor, across the tumor edge and in the peritumoral region which may not be visible on conventional MRI and this may be useful in predicting patient outcomes for operated cerebral metastases.

The reliability of routine clinical post-processing software in assessing potential diffusion-weighted MRI “biomarkers” in brain metastases

BACKGROUND AND PURPOSE Diffusion MRI characteristics have been used as biomarkers to guide prognosis in cerebral pathologies including brain metastases. The measurement of ADC is often described poorly in clinical and research studies with little detail given to the practical considerations of where to place ROIs, which post processing software package to use and how reproducible the resulting metrics will be. METHOD We investigated a series of 12 patients with brain metastases and preoperative DWI. Three post processing platforms were used. ROI were placed over the tumour, peritumoural region and across the brain-tumour interface. These recordings were made by a neurosurgeon and a neuroradiologist. Inter-intra-observer variability was assessed using Bland-Altman analysis. An exploratory analysis of DWI with overall survival and tumour type was made. RESULTS There was excellent correlation between the software packages used for all measures including assessing the whole tumour, selective regions with lowest ADC, the change of ADC across the brain-tumour interface and the relation of the tumour ADC to peritumoural regions and the normal white matter. There was no significant inter- or intra-observer variability for repeated readings. There were significant differences in the mean values obtained using different methodologies and different metrics had differing relationships to overall survival and primary tumour of origin. CONCLUSION Diffusion weighted MRI metrics offer promise as potential non-invasive biomarkers in brain metastases and a variety of metrics have been shown to be reliably measured using differing platforms and observers.