Assessing the diagnostic accuracy and interobserver agreement of MRI perfusion in differentiating disease progression and pseudoprogression following treatment for glioblastoma in a tertiary UK centre.

AIM: To assess the local diagnostic accuracy and interobserver agreement of dynamic susceptibility contrast-enhanced magnetic resonance perfusion (DSC MRP) reporting in differentiating between disease progression and pseudoprogression (PP) at a tertiary UK centre. MATERIALS AND METHODS: This retrospective study included adults with histology-proven glioblastoma who underwent an index DSC MRP examination following treatment. Each index examination was evaluated by three reporters independently, including qualitative assessment and measurement of mean regional cerebral blood volume (rCBVmean) ratios. Consensus opinion was used as the reference standard and considered clinical, radiological and histological follow-up information. Examination reports were compared to each other and to the consensus opinion. RESULTS: Thirty-two cases were included (19 progression, 13 pseudoprogression). Interobserver agreement was fair for qualitative opinion (κ=0.58, 95% confidence interval [CI] 0.40-0.76) and good for rCBVmean ratio measurement (intraclass correlation coefficient [ICC, two-way random effects model] 0.63, 95% CI=0.43-0.78). Qualitative opinion showed diagnostic accuracies of 77.1% (95% CI=67.4-85.1) for progression and 75% (95% CI=65.1-83.3) for pseudoprogression. rCBVmean ratios were higher for progression (6.85 ± 3.98) than pseudoprogression (3.71 ± 3.40); a 3.0 threshold value maximised the sum of sensitivity (91.1%) and specificity (69.7%) on receiver operating characteristic analysis. CONCLUSIONS: DSC MRP and rCBVmean ratio measurement aid differentiation between progression and pseudoprogression following treatment for glioblastoma. Measurement of the rCBVmean ratio shows good interobserver agreement and can change opinion and improve confidence in DSC MRP reporting. Individual centres should validate their own threshold rCBVmean ratio values to optimise diagnostic accuracy.

Spontaneous intracranial hypotension: the role of radiology in diagnosis and management.

Spontaneous intracranial hypotension (SIH) is a condition that results from leakage of cerebrospinal fluid (CSF) from the spine, and which typically presents with debilitating orthostatic headache, but can be associated with a wide range of other symptoms. The causes of spontaneous CSF leaks that lead to SIH include dural tears, leaking meningeal diverticula, and CSF-venous fistulas. Imaging plays a central role in the initial diagnosis of SIH and in its subsequent investigation and management. This article reviews the typical neuroimaging manifestations of SIH and discusses the utility of different myelographic techniques for localising spinal CSF leaks as well as the role of image-guided treatment.

Voxel-based analysis in neuroferritinopathy expands the phenotype and determines radiological correlates of disease severity.

Neuroferritinopathy is an autosomal dominant adult-onset movement disorder which occurs due to mutations in the ferritin light chain gene (FTL). Extensive iron deposition and cavitation are observed post-mortem in the basal ganglia, but whether more widespread pathological changes occur, and whether they correlate with disease severity is unknown. 3D-T1w and quantitative T2 whole brain MRI scans were performed in 10 clinically symptomatic patients with the 460InsA FTL mutation and 10 age-matched controls. Voxel-based morphometry (VBM) and voxel-based relaxometry (VBR) were subsequently performed. Clinical assessment using the Unified Dystonia Rating Scale (UDRS) and Unified Huntington's Disease Rating Scale (UHDRS) was undertaken in all patients. VBM detected significant tissue changes within the substantia nigra, midbrain and dentate together with significant cerebellar atrophy in patients (FWE, p < 0.05). Iron deposition in the caudate head and cavitation in the lateral globus pallidus correlated with UDRS score (p < 0.001). There were no differences between groups with VBR. Our data show that progressive iron accumulation in the caudate nucleus, and cavitation of the globus pallidus correlate with disease severity in neuroferritinopathy. We also confirm sub-clinical cerebellar atrophy as a feature of the disease. We suggest that VBM is an effective technique to detect regions of iron deposition and cavitation, with potential wider utility to determine radiological markers of disease severity for all NBIA disorders.

Single-center experience of cerecyte coils in the treatment of intracranial aneurysms: initial experience and early follow-up results.

BACKGROUND AND PURPOSE: Endovascular treatment of intracranial aneurysms using platinum coils is effective, but uncommonly aneurysms recur. New-generation coils, such as Cerecyte, aim to address this problem. This study examines the safety and efficacy of these coils in the treatment of a cohort of ruptured and unruptured aneurysms MATERIALS AND METHODS: Sixty-seven patients with 68 aneurysms were included in the study. Of these, 51 were treated exclusively with the new polyglycolic acid (PGA)-containing coils, and 17 were treated with a combination of new PGA-containing and other coils. Initial and follow-up angiograms were graded according to the 3-point scale of occlusion. Follow-up angiography was available in 46 cases at 6 months. Based on occlusion grading at initial and follow-up angiography, aneurysms were classified into stable, improved, and worsened (recanalized) groups. RESULTS: Of the exclusive new-coil cohort, 36 cases (70.6%) were initially completely occluded (grade 1), 12 (23.5%) showed filling at the neck (grade 2), and 3 (5.9%) showed contrast within the neck and sac (grade 3). Analysis of the follow-up angiograms showed 24 (70.6%) had stable occlusion, 3 (8.8%) had improved occlusion, and 7 (20.6%) had worsening occlusion. Data for cases treated with new PGA-containing coils together with bare platinum coils were also analyzed separately. Intraprocedural adverse events were noted in 4 cases (7.8%), but there were no clinical sequelae. There were no rebleeds in the follow-up period. CONCLUSION: New PGA-containing coils show no excess in procedural and periprocedural complications over bare platinum coils, and the recanalization rate is comparable with bare platinum coils in the short term.

A case of syringomyelia associated with cervical spondylosis.

Cervical spondylosis is an extremely common condition causing spinal cord compression, and yet it very rarely causes secondary syrinx formation. We report a case of cervical spondylosis with associated syringomyelia and review the possible pathogenesis of this condition.

Reversible cytotoxic cerebral edema in cerebral fat embolism.

We present a case of cerebral fat embolism (CFE) that demonstrated evidence of diffuse white matter cytotoxic edema on diffusion-weighted magnetic resonance imaging, in addition to punctate hyperintensities on T2-weighted and diffusion-weighted imaging. The case suggests that CFE represents a combination of occlusive arteriolar disease and secondary neurotoxicity.

Radiological characterization of spinocerebellar ataxia type 6.

Spinocerebellar ataxia type 6 (SCA-6) is a rare, autosomal dominant neurodegenerative condition characterized by adult onset cerebellar ataxia and ocular movement disorders. The presentation is non-specific, and radiological characterization would be of diagnostic benefit. There is little published on the radiological appearances of SCA-6, and there are conflicting reports in the literature. We report the radiological findings in a group of 10 patients with SCA-6.

Use of colour duplex ultrasound to diagnose giant cell arteritis in a case of visual loss of uncertain aetiology.

Giant cell arteritis is a common condition that can result in permanent visual loss. It has traditionally been diagnosed by invasive temporal artery biopsy in cases of clinical suspicion. The findings of colour duplex ultrasound have recently been described. We report the use of duplex ultrasound to diagnose temporal arteritis, with clinicopathological correlation, and discuss the possible application of this non-invasive technique to the management of giant cell arteritis.

Use of serial proton magnetic resonance spectroscopy to differentiate low grade glioma from tumefactive plaque in a patient with multiple sclerosis.

We report on the use of serial proton MR spectroscopy ((1)H MRS) to differentiate between glioma and tumefactive plaque in a known multiple sclerosis (MS) patient who developed a symptomatic cerebral space occupying lesion. Gliomas and acute MS plaques may have indistinguishable chemical resonance spectra, whereas that of chronic plaque is distinct. In our case (1)H MRS demonstrated elevated concentrations of choline, lactate and lipid, with reduced N-acetyl aspartate, a pattern consistent with either low grade glioma or acute demyelinating plaque. A repeat study 4 months later showed no change, this was felt to be incompatible with the natural history of an acute plaque and low grade glioma was diagnosed. Surgical removal of the lesion revealed an oligodendroglioma, confirming the imaging findings.

Serial MRI in a case of familial hemiplegic migraine.

We report MRI findings in a patient with familial hemiplegic migraine (FHM) with repeated episodes of hemiparesis. FHM is caused by a penetrant autosomal dominant genetic mutation; several mutations have been genotyped, involving brain-expressed ion channels. We found cerebral oedema, dilatation of intracerebral vessels and decreased water diffusion contralateral to the hemiparesis, not respecting vascular territories, with subsequent complete resolution of both clinical and imaging abnormalities. These results are thought to be consistent with an underlying primary neuronal pathology with secondary vascular effects, as opposed to the traditional, primarily vascular, model of migraine aetiology.