Intracranial rheumatoid nodule causing recurrent transient neurological deficits.

A 67-year-old man with rheumatoid arthritis developed recurrent acute onset of stereotyped focal neurological abnormalities. Cerebral imaging showed a mass lesion in the left parieto-occipital lobe. Imaging did not show the time evolution expected in stroke and so he underwent an extensive workup, which was inconclusive. Brain biopsy identified a rheumatoid nodule causing an extensive inflammatory reaction that mimicked a mass. Following treatment with intravenous corticosteroids and rituximab infusions, his clinical condition improved. While rheumatoid meningitis is well recognised, a rheumatoid nodule in the brain rarely presents as a mass lesion. Nevertheless, it is important to consider rheumatoid nodule in the differential diagnosis of a cerebral mass lesion in patients with rheumatoid arthritis.

Multifocal Stroke From Ozone Gas Emboli.

A 34-year-old man with chronic neck pain was treated with regular cervical paravertebral ozone injections. After his last injection, he experienced a syncopal episode and, upon awakening, was found to have ataxia, aphasia, hemiparesis, and left sixth nerve palsy. Computed tomographic angiography demonstrated intra-arterial gas in the right vertebral artery; multiple posterior circulation infarcts were seen on brain MRI. This case illustrates the potential dangers of paravertebral injections of ozone.

Clinical, EEG, MRI, MEG, and surgical outcomes of pediatric epilepsy with astrocytic inclusions versus focal cortical dysplasia.

OBJECTIVE: Astrocytic inclusions (AIs) have been identified on histologic specimens of patients with early onset seizures, and the proteomic contents have been described. The aim of this study was to compare the clinical, electroencephalography (EEG), magnetoencephalography (MEG), magnetic resonance imaging (MRI), and surgical outcomes of AIs relative to focal cortical dysplasia (FCD). METHODS: We assessed the clinical manifestations, semiology, ictal and interictal features on video-EEG, MEG, MRI features, and surgical outcomes of children with histologically proven AIs compared to FCD. RESULTS: Six children had AIs and 27 had FCD. Children with AIs had an earlier age at seizure onset, periodic spasms (all children), and interictal epileptiform discharges consisting of a mixture of generalized or diffuse hemispheric slow waves, sharp waves, spikes and polyspikes. Children with FCD were less likely to have spasms (4/27 [15%]), and the morphology of the diffuse hemispheric or generalized discharges were different from those of AI, consisting of spike-and-waves, polyspike-and-waves, sharp-and-slow waves, and paroxysmal fast activity. Patients with AIs were less likely to have tightly clustered MEG spike sources (3/6 [50%] vs. 23/27 [85%]), and more likely to demonstrate abnormal sulcation and gyration pattern (4/6 [67%] vs. 2/27 [7%]) and gray matter heterotopia (2/6 [33%] vs. 0/27 [0%]) than patients with FCD. Four children with AIs had resection and two had biopsy but did not undergo resection. Children with AIs had lower rates of seizure freedom after surgery compared to FCD (1/4 [25%] vs. 15/27 [56%], respectively). SIGNIFICANCE: Although there were some similarities between AIs and FCD, patients with AIs were more likely to present with early onset periodic spasms, have unusual interictal epileptiform discharges, abnormal sulcation, gyration pattern, and gray matter heterotopia, and were less likely to be seizure free following surgical resection relative to FCD. Further study with a larger sample size is needed to validate our findings.

Inter-rater concordance and operating definitions of radiologic nodal feature assessment in human papillomavirus-positive oropharyngeal carcinoma.

BACKGROUND AND PURPOSE: This study aims to evaluate the reliability of radiologic nodal feature assessment in clinical node-positive human papillomavirus-positive oropharyngeal carcinoma. MATERIALS AND METHODS: Baseline CTs or MRIs of clinical node-positive human papillomavirus-positive oropharyngeal carcinoma diagnosed between 2012 and 2015 were reviewed independently by two neuroradiologists for seven nodal features: radiologic nodal involvement, cystic change, presence of necrosis, clustering, conglomeration, coalescence, and extranodal extension. Consensus operating definitions were derived after discussion. The features were re-reviewed in a randomly selected cohort. Levels of certainty (probability of presence: <25%, ∼50%, ∼75%, and >90%) were recorded. Interrater concordance was calculated using Cohen's kappa coefficient. RESULTS: A total of 413 patients (826 necks) were eligible. At initial review, the inter-rater kappa values for: radiologic nodal involvement, cystic change, necrosis, clustering, conglomeration, coalescence, and extranodal extension were 0.92, 0.64, 0.48, 0.32, 0.32, 0.62, and 0.56, respectively. A re-review of 94 randomly selected cases (188 necks) after consolidation of operating definitions for nodal features showed that the inter-rater kappa values of these features were 0.83, 0.62, 0.58, 0.32, 0.18, 0.68, and 0.74 when considering ≥50% certainty as positive, and improved to 0.94, 0.66, 0.59, 0.33, 0.19, 0.76, and 0.86 when considering ≥75% certainty as positive. CONCLUSION: Clearly defined nomenclature results in improved interrater reliability when assessing radiologic nodal features, especially for coalescent adenopathy and extranodal extension. Higher levels of certainty are associated with higher inter-rater agreement. Radiology reporting should include clear definitions of clinically relevant nodal features as well as levels of certainty to serve various needs in clinical care and research.

Spontaneous Resolution of Dorsal Midbrain Syndrome Caused by a Pineal Cyst.

BACKGROUND: Pineal lesions are common causes of dorsal midbrain syndrome and typically require surgical intervention in symptomatic patients. We describe a unique case of spontaneous resolution of dorsal midbrain syndrome resulting from a pineal gland cyst. CASE DESCRIPTION: A 23-year-old woman developed a supranuclear upgaze palsy, convergence-retraction nystagmus, and light-near dissociation from a pineal gland cyst (1.0 × 1.3 × 1.2 cm) with mild mass effect on the posterior surface of the tectum. Seven days after symptom onset, she had complete, spontaneous resolution of her symptoms, and examination returned to normal. Repeat magnetic resonance imaging demonstrated an unchanged pineal cyst with new T2/fluid attenuated inversion recovery hyperintensity along the mesial surface of the left thalamus. CONCLUSIONS: Dorsal midbrain syndrome resulting from a pineal cyst may spontaneously improve even without a significant change in lesion size. This suggests that observation may be an appropriate initial management strategy.