- Oxygen exposures at NASA's Neutral Buoyancy Lab: a 20-year experience. [Journal Article]
- UHUndersea Hyperb Med 2018 Jul-Aug; 45(4):427-436
- Astronauts training for extravehicular activity (EVA) operations can spend many hours submerged underwater in a pressurized suit, called an extravehicular mobility unit (EMU), exposed to pressures ex...
Astronauts training for extravehicular activity (EVA) operations can spend many hours submerged underwater in a pressurized suit, called an extravehicular mobility unit (EMU), exposed to pressures exceeding 2 atmospheres absolute (ATA). To minimize the risk of decompression sickness (DCS) a 46% nitrox mixture is used. This limits the nitrogen partial pressure, decreasing the risk of DCS. The trade-off with using a 46% nitrox mixture is the increased potential for oxygen toxicity, which can lead to severe neurologic symptoms including seizures. Suited runs, which typically expose astronauts of 0.9-1.1 ATA for longer than six hours, routinely exceed the recommendation for central nervous system oxygen toxicity limits (CNSOTL) published by the National Oceanic and Atmospheric Administration (NOAA). Fortunately, in over 50,000 hours of suited training dives spanning 20 years of EVA training operations at NASA's Neutral Buoyancy Laboratory (NBL) there has never been an occurrence of oxygen toxicity. This lends support to anecdotal sentiment among certain members of the hyperbaric community that the NOAA CNSOTL recommendations might be overly conservative, at least for the oxygen pressure and time regime in which NBL operates. The NOAA CNSOTL recommendations are the result of expert consensus with a focus on safety and do not necessarily reflect rigorous experimental evidence. The data from the NBL suited dive operations provide a foundation of evidence that can help inform the expert discussion on dive-related neurologic oxygen toxicity performance and overnight recovery in young, healthy males.
- Explanatory factors of adherence to community-based management of epilepsy in Lao PDR. [Journal Article]
- EBEpilepsy Behav 2018 Sep 18; 88:74-80
- CONCLUSIONS: A low level of knowledge about epilepsy among health workers, a context of stigmatizing sociocultural beliefs, and a low availability of antiepileptic drugs in Lao People's Democratic Republic (PDR) are major gaps in the medical management of people with epilepsy in this country.A wider range of antiepileptic drugs at a reduced cost and the promotion of adherence to community healthcare would allow a better management of people with epilepsy in Lao PDR.
- Burden of illness in patients with possible Lennox-Gastaut syndrome: A retrospective claims-based study. [Journal Article]
- EBEpilepsy Behav 2018 Sep 18; 88:66-73
- CONCLUSIONS: Patients with possible LGS have significantly higher healthcare utilization and costs than patients without epilepsy or seizures. Our results suggest that direct costs associated with LGS are substantial and highlight the need for new and effective treatments.
- Pharmacotherapy in patients with epilepsy and psychosis. [Review]
- EBEpilepsy Behav 2018 Sep 18; 88:54-60
- The recognition and treatment of psychosis in persons with epilepsy (PWE) is recommended with the apparent dilemma between treating psychosis and opening the possibility of exacerbating seizures. The...
The recognition and treatment of psychosis in persons with epilepsy (PWE) is recommended with the apparent dilemma between treating psychosis and opening the possibility of exacerbating seizures. The pooled prevalence estimate of psychosis in PWE is 5.6%. It has been proposed that a 'two hit' model, requiring both aberrant limbic activity and impaired frontal control, may account for the wide range of clinical phenotypes. The role of antiepileptic drugs in psychosis in PWE remains unclear. Alternating psychosis, the clinical phenomenon of a reciprocal relationship between psychosis and seizures, is unlikely to be an exclusively antiepileptic drug-specific phenomenon but rather, linked to the neurobiological mechanisms underlying seizure control. Reevaluation of antiepileptic treatment, including the agent/s being used and degree of epileptic seizure control is recommended. The authors found very few controlled studies to inform evidence-based treatment of psychosis in PWE. However, antipsychotics and benzodiazepines are recommended as the symptomatic clinical treatments of choice for postictal and brief interictal psychoses. The general principle of early symptomatic treatment of psychotic symptoms applies in epilepsy-related psychoses, as for primary psychotic disorders. In the authors' experience, low doses of antipsychotic medications do not significantly increase clinical risk of seizures in PWE being concurrently treated with an efficacious antiepileptic regimen.
- Psychiatric disorders and trauma history in patients with pure PNES and patients with PNES and coexisting epilepsy. [Journal Article]
- EBEpilepsy Behav 2018 Sep 18; 88:41-48
- Several studies found high prevalence rates of psychiatric disorders in patients with pure psychogenic nonepileptic seizures (PNES). Traumatic experiences were also reported to be elevated in patient...
Several studies found high prevalence rates of psychiatric disorders in patients with pure psychogenic nonepileptic seizures (PNES). Traumatic experiences were also reported to be elevated in patients with PNES and were discussed as a crucial risk factor for the development of PNES. Much less is known about psychiatric comorbidities and specifically, about trauma history in patients with PNES and coexisting epilepsy. Here, we aimed at directly comparing psychiatric disorders and traumatic life experiences in patients with pure PNES and in patients with PNES and coexisting epilepsy. We assessed the presence of current axes I and II disorders in 109 patients with either pure PNES (n = 67) or with PNES + epilepsy (n = 42) by using structured clinical interviews. We also compared the trauma histories by using the posttraumatic diagnostic scale (PDS) as an interview and the extent of physical, sexual, and emotional childhood maltreatment measured with the Childhood Trauma Questionnaire (CTQ). Patients of both groups had very high rates of psychiatric disorders: 79.1% of the patients with pure PNES and 76.2% of the patients with PNES + epilepsy had at least one psychiatric disorder. The frequencies of psychiatric disorders did not differ between groups. However, there was a trend towards higher rates of posttraumatic stress disorder (PTSD) in patients with PNES (32.9%) compared with patients with PNES + epilepsy (16.7%). In both groups, the proportion of patients who recalled traumatic events in the PDS was high (72.6% in the patients with pure PNES, 64.3% in the patients with PNES + epilepsy) and did not differ significantly between groups. The age at first traumatization, the types of trauma events experienced, the number of patients with single traumatization, and those with repeated traumatic experiences also did not differ between groups. We found high frequencies of childhood maltreatment in both groups. Our findings show that patients with PNES and patients with PNES and coexisting epilepsy could neither be differentiated by the amount of psychiatric additional disorders nor by the nature and extent of trauma and maltreatment experiences. Our results suggest that patients with PNES + epilepsy rather resemble patients with pure PNES than patients with epilepsy in respect to psychopathological characteristics and adverse life experiences. Trauma and maltreatment history are therefore assumed to be predisposing factors to PNES in both patients with pure PNES and patients with PNES and coexisting epilepsy.
- Intracranial meningeal Rosai-Dorfman disease mimicking multiple meningiomas: Three case reports and a literature review. [Journal Article]
- WNWorld Neurosurg 2018 Sep 18
- CONCLUSIONS: RDD with multiple isolated intracranial foci is rare but should be considered as a differential diagnosis when multiple meningiomas are suspected in children and adults. This short series suggests that preoperative diagnosis is challenging, and the definitive diagnosis requires immunohistochemical examination. Currently, surgical resection is the most effective therapy for the rapid relief of symptoms.
- Evidence for peri-ictal blood-brain barrier dysfunction in patients with epilepsy. [Journal Article]
- BBrain 2018 Sep 19
- Epilepsy has been associated with a dysfunction of the blood-brain barrier. While there is ample evidence that a dysfunction of the blood-brain barrier contributes to epileptogenesis, blood-brain bar...
Epilepsy has been associated with a dysfunction of the blood-brain barrier. While there is ample evidence that a dysfunction of the blood-brain barrier contributes to epileptogenesis, blood-brain barrier dysfunction as a consequence of single epileptic seizures has not been systematically investigated. We hypothesized that blood-brain barrier dysfunction is temporally and anatomically associated with epileptic seizures in patients and used a newly-established quantitative MRI protocol to test our hypothesis. Twenty-three patients with epilepsy undergoing inpatient monitoring as part of their presurgical evaluation were included in this study (10 females, mean age ± standard deviation: 28.78 ± 8.45). For each patient, we acquired quantitative T1 relaxation time maps (qT1) after both ictal and interictal injection of gadolinium-based contrast agent. The postictal enhancement of contrast agent was quantified by subtracting postictal qT1 from interictal qT1 and the resulting ΔqT1 was used as a surrogate imaging marker of peri-ictal blood-brain barrier dysfunction. Additionally, the serum concentrations of MMP9 and S100, both considered biomarkers of blood-brain barrier dysfunction, were assessed in serum samples obtained prior to and after the index seizure. Fifteen patients exhibited secondarily generalized tonic-clonic seizures and eight patients exhibited focal seizures at ictal injection of contrast agent. By comparing ΔqT1 of the generalized tonic-clonic seizures and focal seizures groups, the anatomical association between ictal epileptic activity and postictal enhancement of contrast agent could be probed. The generalized tonic-clonic seizures group showed significantly higher ΔqT1 in the whole brain as compared to the focal seizures group. Specific analysis of scans acquired later than 3 h after the onset of the seizure revealed higher ΔqT1 in the generalized tonic-clonic seizures group as compared to the focal seizures group, which was strictly lateralized to the hemisphere of seizure onset. Both MMP9 and S100 showed a significantly increased postictal concentration. The current study provides evidence for the occurrence of a blood-brain barrier dysfunction, which is temporally and anatomically associated with epileptic seizures. qT1 after ictal contrast agent injection is rendered as valuable imaging marker of seizure-associated blood-brain barrier dysfunction and may be measured hours after the seizure. The observation of the strong anatomical association of peri-ictal blood-brain barrier dysfunction may spark the development of new functional imaging modalities for the post hoc visualization of brain areas affected by the seizure.
- Postcranioplasty seizures following decompressive craniectomy and seizure prophylaxis: a retrospective analysis at a single institution. [Journal Article]
- JNJ Neurosurg 2018 Sep 21; :1-5
- CONCLUSIONS: Cranioplasty is associated with a high incidence of postoperative seizures. The prophylactic use of AEDs can reduce the occurrence of early seizures.
- Nationwide incidence and risk factors for posttraumatic seizures in children with traumatic brain injury. [Journal Article]
- JNJ Neurosurg Pediatr 2018 Sep 21; :1-10
- CONCLUSIONS: PTS is common in children with TBI and is associated with adverse outcomes. Independent risk factors for PTS include younger age (< 5 years), African American race, increased preexisting comorbidity, prolonged LOC, and injury pattern involving cortical exposure to blood products. However, patients who undergo urgent surgical evacuation are less likely to develop PTS.
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- Typical asymmetry in the hemispheric activation during an fMRI verbal comprehension paradigm is related to better performance in verbal and non-verbal tasks in patients with epilepsy. [Journal Article]
- NCNeuroimage Clin 2018 Sep 15; 20:742-752
- Chronic exposure to seizures in patients with left hemisphere (LH) epileptic focus could favor higher activation in the contralateral hemisphere during language processing, but the cognitive effects ...
Chronic exposure to seizures in patients with left hemisphere (LH) epileptic focus could favor higher activation in the contralateral hemisphere during language processing, but the cognitive effects of this remain unclear. This study assesses the relationship between asymmetry in hemispheric activation during language fMRI and performance in verbal and non-verbal tasks. Whereas prior studies primarily used fMRI paradigms that favor frontal lobe activation and less prominent activation of the medial or superior temporal lobes, we used a verbal comprehension paradigm previously demonstrated to activate reliably receptive language areas. Forty-seven patients with drug-resistant epilepsy candidates for surgery underwent a multidisciplinary assessment, including a comprehensive neuropsychological evaluation and an fMRI verbal comprehension paradigm. Patients were distributed in two groups depending on laterality indexes (LI): typical hemispheric asymmetry (unilateral left activation preponderance; n = 23) and atypical hemispheric asymmetry (bilateral or unilateral right preponderance; n = 24). Right-handedness and right hemisphere (RH) focus were significant predictors of typical asymmetry. Patients with typical activation pattern presented better performance intelligence quotient and verbal learning than patients with atypical hemispheric asymmetry (for all, p < 0.014). Patients with LH focus had more frequently atypical hemispheric asymmetry than patients with RH focus (p = 0.05). Specifically, they showed lower LI and this was related to worse performance in verbal and non-verbal tasks. In conclusion, an increased activation of homologous RH areas for verbal comprehension processing could imply a competition of cognitive resources in the performance of the same task, disrupting cognitive performance.