19 research outputs found

    A new era of wide-field submillimetre imaging: on-sky performance of SCUBA-2

    Full text link
    SCUBA-2 is the largest submillimetre wide-field bolometric camera ever built. This 43 square arc-minute field-of-view instrument operates at two wavelengths (850 and 450 microns) and has been installed on the James Clerk Maxwell Telescope on Mauna Kea, Hawaii. SCUBA-2 has been successfully commissioned and operational for general science since October 2011. This paper presents an overview of the on-sky performance of the instrument during and since commissioning in mid-2011. The on-sky noise characteristics and NEPs of the 450 and 850 micron arrays, with average yields of approximately 3400 bolometers at each wavelength, will be shown. The observing modes of the instrument and the on-sky calibration techniques are described. The culmination of these efforts has resulted in a scientifically powerful mapping camera with sensitivities that allow a square degree of sky to be mapped to 10 mJy/beam rms at 850 micron in 2 hours and 60 mJy/beam rms at 450 micron in 5 hours in the best weather.Comment: 18 pages, 15 figures.SPIE Conference series 8452, Millimetre, Submillimetre and Far-infrared Detectors and Instrumentation for Astronomy VI 201

    APOE ɛ4 is associated with postictal confusion in patients with medically refractory temporal lobe epilepsy

    Get PDF
    This study examined the relationship between the APOE ɛ4 allele and postictal confusion in patients with medically intractable temporal lobe epilepsy (TLE). Patients with at least one ɛ4 allele (n = 22) were three times more likely to exhibit postictal confusion (68%) than the 63 patients without ɛ4 (43%). These preliminary results demonstrate that APOE ɛ4 is associated with an increased risk of postictal confusion in patients with medically intractable TLE, suggesting possible dysfunction in neuronal recovery mechanisms

    Assessment of depression in epilepsy: the utility of common and disease-specific self-report depression measures

    No full text
    OBJECTIVES: Depression is common in epilepsy, with rates ranging from 20 to 55% in most samples and reports as high as 70% in patients with intractable epilepsy. However, some contend that depression may be over- and/or under-reported and treated in this population. This may be due to the use of common self-report depression measures that fail to take into account the overlap of disease and depressive symptoms and also the host of side effects associated with antiepileptic medication, which may also be construed as depression. METHODS: The present study examined the utility of common self-report depression measures and those designed specifically for the medically ill, including a proposed new measure, to determine which may be more appropriate for use among people with epilepsy. RESULTS: We found that common self-report depression measures are useful for screening depression in epilepsy, particularly with a raised cutoff for one, with sensitivities ranging from .91 to .96. A measure designed for the medically ill obtained the greatest specificity of .91, suggesting its use as a diagnostic tool with a slightly raised cutoff. The positive likelihood ratio of this latter measure was 8.76 with an overall classification accuracy of 88%. CONCLUSIONS: Assessment of depression in epilepsy can be improved when utilizing self-report measures that better differentiate disease symptoms from neurovegetative symptoms of depression (e.g. fatigue, sleep disturbance). This was demonstrated in the present study. Clinical implications are discussed

    Estimating risk of word-finding problems in adults undergoing epilepsy surgery

    No full text
    OBJECTIVE: This retrospective, observational study examined the frequency and magnitude of change in naming ability as a function of side/site of epilepsy surgery and identified predictive factors to assist clinicians in identifying patients at low, moderate, or high risk of postoperative naming decline. METHODS: A total of 875 adults with pharmacoresistant epilepsy (454 left/421 right; 763 temporal/87 frontal/25 posterior quadrant) met inclusion criteria and completed the Boston Naming Test before and after surgery. Clinically meaningful change in naming ability was assessed using reliable change indices for epilepsy. Demographic, cognitive, and seizure variables were examined to determine factors most predictive of naming decline and to develop a decision tree to assist with clinical decision-making. RESULTS: Naming decline was rare in right-sided resections and did not exceed the level expected by chance (5% overall; 90% confidence interval [CI] ± 2%). Naming decline occurred in 41% (CI ± 5%) of patients after left temporal resection (TLR) compared to 10%-12% (CI ± 10%-19%) in other left-sided surgical groups. A sizable proportion of left TLR patients (17%; CI ± 4%) showed substantial declines in naming (\u3e11 points). Decline following left TLR was related to later age at seizure onset, older age at surgery, and higher preoperative naming ability. These factors correctly predicted naming decline in 68% of patients and were associated with degree of decline following left TLR. A decision tree is provided to assist clinicians in identifying patients at low, moderate, or high risk for postoperative naming declines. CONCLUSIONS: In addition to discussions regarding risk for memory decline following left TLR, patients should be counseled about potential decline in word-finding ability

    Effect of Apolipoprotein ε4 on Hippocampal and Brain Volume in Intractable Temporal Lobe Epilepsy

    No full text
    This study investigated the relationship between the apolipoprotein (APOE) ε4 allele and brain volumes in patients with medically intractable temporal lobe epilepsy (TLE). MRI-based volumetric analyses of the hippocampi, cerebral hemispheres, and whole brain were conducted in 59 patients with TLE (31 with left TLE, 28 with right TLE) with hippocampal sclerosis (HS). There were no differences in hippocampal, hemispheric, or whole brain volumes as a function of ε4 status even after correcting for hemispheric and total brain volumes. However, APOE ε4 carriers showed a trend toward having a smaller discrepancy between ipsilateral and contralateral hippocampal volumes than patients without this allele, and post hoc analyses suggest there may be an increased incidence of bilateral HS in ε4 carriers. In summary, APOE ε4 is not associated with significant hippocampal, hemispheric, or whole brain atrophy in patients with medically intractable TLE. However, ε4 carriers may be more likely to have bilateral HS, with an apparent dose-dependent effect
    corecore