The refractory epilepsy screening tool for Lennox-Gastaut syndrome (REST-LGS).

BACKGROUND: The complex clinical presentation and progression of Lennox-Gastaut syndrome (LGS) can complicate the accurate diagnosis of this severe, lifelong, childhood-onset epilepsy, often resulting in suboptimal treatment. The Refractory Epilepsy Screening Tool for LGS (REST-LGS) was developed to improve the identification of patients with LGS. METHODS: Using the Modified Delphi Consensus, a group of experts developed and tested the REST-LGS Case Report Form (CRF) comprising 8 criteria (4 major, 4 minor) considered potentially indicative of LGS. Diagnosis-blinded specialist and nonspecialist raters at 2 epilepsy centers applied the CRF to deidentified patient records, including 1:1 records of patients with drug-resistant epilepsy or confirmed LGS. Interrater reliability was measured by Cohen's κ. Diagnosis was then unblinded to reveal common criteria for LGS or drug-resistant epilepsy. Cronbach's α was used to measure internal consistency between raters for all criteria combined. RESULTS: Of 200 patients, 81% to 85% met 1 to 3 major criteria. At both sites, moderate (κ, 0.41-0.60) to good (κ, 0.61-0.80) agreement on most criteria was reached between expert and nonexpert raters. Unblinding revealed that most patients with LGS met 3 major and 2 to 3 minor criteria, while patients with drug-resistant epilepsy met ≤1 major and only 1 to 2 minor criteria. Cronbach's α of raters at both sites was 0.64. CONCLUSIONS: The combined number of major/minor criteria on the CRF may be particularly indicative of LGS. Therefore, the REST-LGS may be a valuable clinical tool in identifying patients requiring further diagnostic evaluation for LGS.

A hybrid multibreath wash-in wash-out lung function quantification scheme in human subjects using hyperpolarized 3 He MRI for simultaneous assessment of specific ventilation, alveolar oxygen tension, oxygen uptake, and air trapping.

PURPOSE: To present a method for simultaneous acquisition of alveolar oxygen tension (PA O2 ), specific ventilation (SV), and apparent diffusion coefficient (ADC) of hyperpolarized (HP) gas in the human lung, allowing reinterpretation of the PA O2 and SV maps to produce a map of oxygen uptake (R). METHOD: An imaging scheme was designed with a series of identical normoxic HP gas wash-in breaths to measure ADC, SV, PA O2 , and R in less than 2 min. Signal dynamics were fit to an iterative recursive model that regionally solved for these parameters. This measurement was successfully performed in 12 subjects classified in three healthy, smoker, and chronic obstructive pulmonary disease (COPD) cohorts. RESULTS: The overall whole lung ADC, SV, PA O2 , and R in healthy, smoker, and COPD subjects was 0.20 ± 0.03 cm2 /s, 0.39 ± 0.06,113 ± 2 Torr, and 1.55 ± 0.35 Torr/s, respectively, in healthy subjects; 0.21 ± 0.03 cm2 /s, 0.33 ± 0.06, 115.9 ± 4 Torr, and 0.97 ± 0.2 Torr/s, respectively, in smokers; and 0.25 ± 0.06 cm2 /s, 0.23 ± 0.08, 114.8 ± 6.0Torr, and 0.94 ± 0.12 Torr/s, respectively, in subjects with COPD. Hetrogeneity of SV, PA O2 , and R were indicators of both smoking-related changes and disease, and the severity of the disease correlated with the degree of this heterogeneity. Subjects with symptoms showed reduced oxygen uptake and specific ventilation. CONCLUSION: High-resolution, nearly coregistered and quantitative measures of lung function and structure were obtained with less than 1 L of HP gas. This hybrid multibreath technique produced measures of lung function that revealed clear differences among the cohorts and subjects and were confirmed by correlations with global lung measurements. Magn Reson Med 78:611-624, 2017. © 2016 International Society for Magnetic Resonance in Medicine.

Electrocorticography reveals spatiotemporal neuronal activation patterns of verbal fluency in patients with epilepsy.

Verbal fluency is commonly used to evaluate cognitive dysfunction in a variety of neuropsychiatric diseases, yet the neurobiology underlying performance of this task is incompletely understood. Electrocorticography (ECoG) provides a unique opportunity to investigate temporal activation patterns during cognitive tasks with high spatial and temporal precision. We used ECoG to study high gamma activity (HGA) patterns in patients undergoing presurgical evaluation for intractable epilepsy as they completed an overt, free-recall verbal fluency task. We examined regions demonstrating changes in HGA during specific timeframes relative to speech onset. Early pre-speech high gamma activity was present in left frontal regions during letter fluency and in bifrontal regions during category fluency. During timeframes typically associated with word planning, a distributed network was engaged including left inferior frontal, orbitofrontal and posterior temporal regions. Peri-Rolandic activation was observed during speech onset, and there was post-speech activation in the bilateral posterior superior temporal regions. Based on these observations in the context of prior studies, we propose a model of neocortical activity patterns underlying verbal fluency.