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Kurt Hecox

Publications and source records attributed to Kurt Hecox.

5 recordsLinked to original sources
PubMed2006

A cortical potential imaging study from simultaneous extra- and intracranial electrical recordings by means of the finite element method.

In the present study, we have validated the cortical potential imaging (CPI) technique for estimating cortical potentials from scalp EEG using simultaneously recorded electrocorticogram (ECoG) in the presence of strong local inhomogeneity, i.e., Silastic ECoG grid(s). The finite element method (FEM) was used to model the realistic postoperative head volume conductor, which includes the scalp, skull, cerebrospinal fluid (CSF) and brain, as well as the Silastic ECoG grid(s) implanted during the surgical evaluation in epilepsy patients, from the co-registered magnetic resonance (MR) and computer tomography (CT) images. A series of computer simulations were conducted to evaluate the present FEM-based CPI technique and to assess the effect of the Silastic ECoG grid on the scalp EEG forward solutions. The present simulation results show that the Silastic ECoG grid has substantial influence on the scalp potential forward solution due to the distortion of current pathways in the presence of the extremely low conductive materials. On the other hand, its influence on the estimated cortical potential distribution is much less than that on the scalp potential distribution. With appropriate numerical modeling and inverse estimation techniques, we have demonstrated the feasibility of estimating the cortical potentials from the scalp EEG with the implanted Silastic ECoG gird(s), in both computer simulations and in human experimentation. In an epilepsy patient undergoing surgical evaluation, the cortical potentials were reconstructed from the simultaneously recorded scalp EEG, in which main features of spatial patterns during interictal spike were preserved and over 0.75 correlation coefficient value was obtained between the recorded and estimated cortical potentials. The FEM-based CPI technique provides a means of connecting the simultaneous recorded ECoG and the scalp EEG and promises to become an effective tool to evaluate and validate CPI techniques using clinic data.

Algorithms↗
PubMed2006

Low incidence of subdural grid-related complications in prolonged pediatric EEG monitoring.

Invasive EEG monitoring is one of the best tools available for localization of epileptogenic foci in the brain. However, published data in mixed series of adult and pediatric patients show high incidence of epidural bacterial contamination, cerebrospinal fluid leakage, and skin infection after subdural electrode implantation. We sought to determine whether the complication rate from prolonged subdural electrode implantation would be lower in a purely pediatric series. Thirty-three subdural electrode implantation procedures were performed in 29 pediatric patients (age range 4-19) for an average of 7.2 days (range 3-14 days). Electrode number varied from 32 to >128 with a range of 4-11 electrode wires piercing the skin >1 cm from the primary incision. Of the 33 implantations and resections (66 craniotomies), 5 were for reimplantation. There were no permanent complications related to grid implantation. Transient complications included 1 case of prolonged prothrombin time and 1 patient with unexplained fever, both of which resolved upon removal of the grids. There were two culture-positive infections, one epidural and one superficial, both in patients undergoing reimplantation. There was no percutaneous cerebrospinal fluid leakage noted and no operation was aborted due to bleeding caused by grid placement. Our data suggest that subdural grid implantation in children is remarkably safe even for prolonged implantation, though infectious risk is significantly higher in reoperation (p = 0.019). This observation may contribute to lowering the threshold for two-stage invasive monitoring approaches in children with epilepsy.

Adolescent↗
PubMed2005

Neurodevelopmental outcomes of premature infants treated with inhaled nitric oxide.

BACKGROUND: Chronic lung disease and severe intraventricular hemorrhage or periventricular leukomalacia in premature infants are associated with abnormal neurodevelopmental outcomes. In a previous randomized, controlled, single-center trial of premature infants with the respiratory distress syndrome, inhaled nitric oxide decreased the risk of death or chronic lung disease as well as severe intraventricular hemorrhage and periventricular leukomalacia. We hypothesized that infants treated with inhaled nitric oxide would also have improved neurodevelopmental outcomes. METHODS: We conducted a prospective, longitudinal follow-up study of premature infants who had received inhaled nitric oxide or placebo to investigate neurodevelopmental outcomes at two years of corrected age. Neurologic examination, neurodevelopmental assessment, and anthropometric measurements were made by examiners who were unaware of the children's original treatment assignment. RESULTS: A total of 138 children (82 percent of survivors) were evaluated. In the group given inhaled nitric oxide, 17 of 70 children (24 percent) had abnormal neurodevelopmental outcomes, defined as either disability (cerebral palsy, bilateral blindness, or bilateral hearing loss) or delay (no disability, but one score of less than 70 on the Bayley Scales of Infant Development II), as compared with 31 of 68 children (46 percent) in the placebo group (relative risk, 0.53; 95 percent confidence interval, 0.33 to 0.87; P=0.01). This effect persisted after adjustment for birth weight and sex, as well as for the presence or absence of chronic lung disease and severe intraventricular hemorrhage or periventricular leukomalacia. The improvement in neurodevelopmental outcome in the group given inhaled nitric oxide was primarily due to a 47 percent decrease in the risk of cognitive impairment (defined by a score of less than 70 on the Bayley Mental Developmental Index) (P=0.03). CONCLUSIONS: Premature infants treated with inhaled nitric oxide have improved neurodevelopmental outcomes at two years of age.

Administration, Inhalation↗
PubMed2003

An assessment of the mental health of physicians specializing in the field of child neurology.

We assessed physicians working in the field of child neurology with the aim of improving the physicians' mental health. Our questionnaire included a burnout inventory and a general health questionnaire. We analyzed 29 responses from physicians in a variety of countries obtained through the Internet. According to their responses, 8 (27.5%) of the respondents had attained a burnout status, and 27 respondents (93.1%) had neurotic conditions. We found a greater percentage of physicians in poor mental health than we had found previously in assessments made in Japan. However, the respondents in the present survey had more positive styles for coping with stress. The length of time working as a physician affected respondents in Japan and internationally, whereas nationality or working environment (workplace, night shifts, and so on) did not. Consultants or mentors on work and assertive stress coping would be effective.

Adaptation, Psychological↗