Suffering and divine impassibility.

Many theologians believe in the doctrine of divine impassibility: that God does not experience pain or pleasure from the actions of creation. However, the question inevitably touches upon our personal relationship and journey with God, a journey involving deep joys and pains. This discussion of divine impassibility relates to the medical profession, which seeks to heal the sick and comfort the dying.

Healthcare Engineering Defined: A White Paper.

Engineering has been playing an important role in serving and advancing healthcare. The term "Healthcare Engineering" has been used by professional societies, universities, scientific authors, and the healthcare industry for decades. However, the definition of "Healthcare Engineering" remains ambiguous. The purpose of this position paper is to present a definition of Healthcare Engineering as an academic discipline, an area of research, a field of specialty, and a profession. Healthcare Engineering is defined in terms of what it is, who performs it, where it is performed, and how it is performed, including its purpose, scope, topics, synergy, education/training, contributions, and prospects.

Automated epilepsy diagnosis using interictal scalp EEG.

Over 50 million people worldwide suffer from epilepsy. Traditional diagnosis of epilepsy relies on tedious visual screening by highly trained clinicians from lengthy EEG recording that contains the presence of seizure (ictal) activities. Nowadays, there are many automatic systems that can recognize seizure-related EEG signals to help the diagnosis. However, it is very costly and inconvenient to obtain long-term EEG data with seizure activities, especially in areas short of medical resources. We demonstrate in this paper that we can use the interictal scalp EEG data, which is much easier to collect than the ictal data, to automatically diagnose whether a person is epileptic. In our automated EEG recognition system, we extract three classes of features from the EEG data and build Probabilistic Neural Networks (PNNs) fed with these features. We optimize the feature extraction parameters and combine these PNNs through a voting mechanism. As a result, our system achieves an impressive 94.07% accuracy.

A study to determine the accuracy of a computerized algorithm for interpretation of EEGs.

The main use of computerized EEG has been in sleep studies. A comprehensive system of interpreting routine EEGs by computers has not yet been developed and is technically difficult. We have tried to incorporate computers in the analysis and interpretation of EEGs by using information obtained from visual analysis of EEG in the present work. The purpose of this study was to determine the accuracy of such an algorithm. An electroencephalographer visually analyzed routine EEGs and the data was entered into an EEG Worksheet. The electroencephalographer then interpreted the data and a report was dictated and transcribed. Data from the EEG Worksheet was entered into a computer for interpretation, clinical correlation, and report preparation. Results indicate that the algorithm used with the EEG Worksheet can correctly interpret and clinically correlate visually-analyzed EEG data entered into a computer and reduce time for EEG report generation.

Functional reorganization of motor cortex due to brain tumor: a case report.

We report the case of a 39-year-old man with a brain tumor and 12 years of intractable partial epilepsy with secondary generalization. After extensive noninvasive and invasive evaluation the seizure focus was localized to the right fronto-parietal region. Functional cortical mapping (FCM) was performed after craniotomy and implantation of a subdural grid with 40 electrodes covering the epileptogenic focus and the adjacent cortex. A Grass Model S12 Stimulator was used to deliver gradual increments of current and stimulus duration with fixed frequency of 10 Hz and pulse duration of 500 microsec for defining eloquent cortex next to the seizure focus. FCM demonstrated cortical representation of eye anterior to and hand posterior and inferior to expected locations on the motor cortex compared to the classical homunculus. Subsequently, he underwent resection of an oligodendroglioma. This case demonstrates that the brain undergoes reorganization of cortical motor representation as a result of pathological lesions in the brain.

Zonisamide: a new antiepileptic drug.

Zonisamide (ZNS) is a relatively new antiepileptic medication currently available in Japan. Attempts to market the drug in the United States were thwarted by reports of nephrolithiasis by European and American investigators. However, successful marketing of the drug in Japan has resulted in a renewed interest in bringing the drug to the United States. Japanese experience with ZNS showed a broad spectrum of efficacy in the treatment of seizures, including infantile spasms and myoclonic seizures. A neuroprotective role and an antimanic effect have also been reported. The exact antiepileptic mechanism of action of ZNS is not known, but it has dose-dependent sodium channel blocking and T-type calcium channel blocking properties and free radical scavenging actions. Recommended initial adult dosage in Japan is 100-200 mg/d, increased if necessary to 200-400 mg/d, up to a maximum of 600 mg/d. In children, initial dosage is 2-4 mg/kg/d, increased if necessary to 4-8 mg/kg/d up to a maximum of 12 mg/kg/d. The recommended therapeutic plasma ZNS concentration is 10-20 mg/L. Adverse events, most notably drowsiness, loss of appetite, gastrointestinal problems, and CNS toxicity, have been noted with plasma ZNS concentrations of > 30 mg/L. A drug rash also has been reported.

Cerebral blood flow and temporal lobe epileptogenicity.

Long-term surface cerebral blood flow (CBF) monitoring was performed to test the hypothesis that temporal lobe epileptogenicity is a function of epileptic cortical perfusion. Forty-three bitemporal 2-hour periictal CBF studies were performed in 13 patients. Homotopic regions of temporal cortex maintained interictal epileptic cortical hypoperfusion and nonepileptic normal cortical CBF. At 10 minutes preictus, a statistically significant, sustained increase in CBF was detected on the epileptic temporal lobe. Two minutes preictus, there was approximation of CBF in the epileptic and nonepileptic temporal lobes. Thereafter, electrocorticographic (ECoG) and clinical seizure onset occurred. The linear relationship between CBF in the two hemispheres (epileptic and nonepileptic) was the inverse of normal (y = -0.347x + 62.767, r = 0.470, df = 95, p < 0.05). The data indicated a direct linear correlation between epileptic cortical CBF and seizure interval (frequency-1), a clinical measure of epileptogenicity (r = 0.610, df = 49, p < 0.05). Epileptogenicity was also found to be a logarithmic function of the difference between nonepileptic and epileptic cortical perfusion (r = 0.564, df = 58, t = 5.20, p < 0.05). The results showed that progressive hypoperfusion of the epileptic focus correlated with a decreased seizure interval (increased epileptogenicity). Increased perfusion of the epileptic focus correlated with an increased seizure interval (decreased epileptogenicity). The fact that CBF alterations precede ECoG seizure activity suggests that vasomotor changes may produce electrical and clinical seizure onset.

Response of human epileptic temporal lobe cortical blood flow to hyperventilation.

Bilateral long-term surface cortical cerebral blood flow (CBF) and electrocorticographic (ECoG) monitoring were performed in eight patients with complex partial seizures. In each patient, the epileptic temporal lobe was localized using ictal ECoG. Mean seizure interval (frequency-1) off anticonvulsant medication, a clinical measure of epileptogenicity, was 1.0 +/- 0.3 h (range: 0.4 to 2.5 h). During 13 interictal hyperventilation periods, 3.6 +/- 0.6 min in duration, the mean decrease in epileptic and nonepileptic temporal cortical CBF was 13.7 +/- 2.3 versus 6.4 +/- 1.9 ml/(100 g min) (t = 2.230, d.f. = 16, P < 0.05), representing 20.9% and 10.8% reduction from baseline CBF during hyperventilation, respectively. Seizure interval decreased (i.e. frequency increased) with increasing magnitude of seizure focus CBF reduction during hyperventilation. Seizure interval was significantly correlated with epileptic temporal lobe CBF decrease during hyperventilation (R = 0.763, d.f. = 5, P < 0.05). The data suggest that, compared to nonepileptic brain, epileptic temporal lobe is particularly prone to hypoperfusion during hyperventilation. Epileptogenicity is a function of this seizure focus susceptibility to ischemia. The finding of abnormal seizure focus autoregulation during hyperventilation has implication for epileptic focus localization with cerebral blood flow analysis.

Long-term surface cortical cerebral blood flow monitoring in temporal lobe epilepsy.

Long-term subdural surface cortical cerebral blood flow (CBF) and electrocorticographic monitoring was performed in 12 patients with complex partial seizures. A total of 40 seizures were analyzed. Baseline CBF values from nonepileptic and epileptic temporal lobe (mean +/- standard error) were 60.0 +/- 1.0 and 50.2 +/- 1.8 ml/100 g per minute, respectively (P < 0.05). In general, clinical seizure onset was preceded by a 20-minute preictal CBF increase from baseline in the epileptic temporal lobe. Peak early postictal CBF values of nonepileptic and epileptic temporal lobes were 57.7 +/- 13.3 and 89.0 +/- 21.7 ml/100 g per minute (P > 0.05) at 5.2 +/- 2.2 and 2.4 +/- 1.0 minutes (P > 0.05) after clinical seizure onset, respectively. Statistically significant differences between nonepileptic and epileptic temporal lobe CBF were detected at 50 minutes (74.0 +/- 14.2 and 37.5 +/- 9.2 ml/100 g per minute, respectively; P < 0.05) and 60 minutes (75.6 +/- 13.6 and 36.1 +/- 8.5 ml/100 g per minute, respectively; P < 0.05) postictal. The data suggest that the optimal times for CBF analysis to differentiate epileptic from nonepileptic temporal lobe are 1) during the interictal period and 2) late (50 to 60 minutes) postictal. The results of this study should improve the understanding of the dynamic cerebral perfusion patterns in the epileptic human brain.

Long-term subdural strip electrocorticographic monitoring of ictal déjà vu.

We report a series of 8 patients with ictal déjà vu. Subdural strip electrocorticographic (ECoG) monitoring localized the ictal epileptogenic focus as follows: right (n = 6) and left (n = 2) mesiotemporal lobe. In all 8 patients, the left hemisphere was dominant for language function based on intracarotid amytal testing. In 6 right-handed patients, ictal déjà vu was associated with a right temporal lobe focus. However, in the 2 left-handed patients, the ictal focus was left temporal lobe. Although ictal déjà vu localizes the epileptic focus to temporal lobe, this experimental phenomenon appears to lateralize to the hemisphere nondominant for handedness.

Quantitative analysis of the EEG in the intracarotid amobarbital procedure. I. Amplitude analysis.

Thirty-seven subjects underwent bilateral internal carotid artery injections of amobarbital prior to surgery for intractable epilepsy. The electroencephalogram (EEG) of these patients was continuously monitored during these 74 procedures and was later subjected to quantitative analysis. Topographic mapping of these data suggested that the areas of inactivation were largely restricted to the anterior 2/3 of the hemisphere injected, corresponding to the vascular distributions of the anterior and middle cerebral arteries. Graphical representation of the data demonstrated that delta and theta band activity peaked in the first 2 min post injection and decreased gradually thereafter, becoming stable at around 12 min post injection. Examination of the alpha, beta 1, and beta 2 bands suggested that activity increased and decreased more gradually than that for delta and theta, with perhaps a longer latency. Although EEG changes were most prominent in the anterior 2/3 of the inactivated hemisphere, similar (though smaller) changes were also observed in both ipsilateral and contralateral zones thought to be outside of the vascular distribution of the internal carotid artery.

Affective self-report during the intracarotid sodium amobarbital test.

Changes in internal affective state were investigated in patients undergoing the intracarotid sodium amobarbital test. It was found that when the left hemisphere was inactivated, patients rated their mood as significantly more negative than during baseline conditions. No significant change in affective state was observed during the inactivation of the right hemisphere. The findings are interpreted in terms of a differential lateralization model of emotion, in which the right hemisphere is more involved in the more powerful and salient negative affects.

Silent solitary right parietal chondroma resulting in secondary mania.

We are reporting a case of manic depressive illness in a patient with a falxial chondroma in the right parietal region. Neurological symptoms were absent except for right hemicranial headache and examination was normal, prior to the presentation with mania. The mania responded to psychotropics. Subsequent evaluation with a head CT scan using contrast enhancement showed a 2.5 x 2 cm high density mass which on craniotomy and biopsy was noted to be a chondroma. For two years following removal, the patient remained euthymic without medication. To our knowledge, this is the fourth reported case of a chondroma in the parietal region and the first case of secondary mania associated with such a tumor.

The association of multiple personality and temporolimbic epilepsy. Intracarotid amobarbital test observations.

OBJECTIVE: What is the relationship of "multiple personality disorder" in patients with temporolimbic epilepsy to certain types of hemispheric interaction? DESIGN: Case series. SETTING: Tertiary care referral center. PATIENTS: Two patients with temporolimbic epilepsy considered to be surgical candidates referred for the intracarotid amobarbital sodium procedure (IAP). Each individual had presented with different "personalities" in a characteristic temporal relationship to their seizures. INTERVENTIONS: Intracarotid amobarbital sodium procedure, Wada test, and electroencephalogram. MAIN OUTCOME MEASURES: Behavioral observations made during the performance of the IAP. RESULTS: During the IAP, each patient's peri-ictal "personality" changes were precisely replicated. No seizure activity was noted during the IAPs. CONCLUSIONS: These observations suggest that the association of multiple personality and temporolimbic epilepsy is not dependent on seizure discharges per se, but rather may be related to certain types of hemispheric interaction.

Lumbar cerebral spinal fluid drainage during long-term electrocorticographic monitoring with subdural strip electrodes: elimination of cerebral spinal fluid leak.

We performed this study to determine the efficacy of continuous lumbar cerebral spinal fluid (CSF) drainage in controlling CSF leak during subdural strip electrode monitoring of epilepsy patients. Subdural strip electrodes were placed in 14 patients. In seven patients, a lumbar sub-arachnoid catheter was placed for continuous CSF drainage. In seven patients, no lumbar drain was placed. The duration of scalp CSF leak during strip electrode monitoring was significantly reduced in patients undergoing lumbar CSF drainage compared to those without lumbar drains (chi 2 = 40.9, P < 0.05). In one patient spinal headache developed which resolved with lumbar drain removal. Lumbar drainage eliminates scalp CSF leakage and can improve patient comfort. This technique should be further studied to determine if it reduces infection risk during long-term invasive monitoring.

Efficacy and safety of zonisamide: results of a multicenter study.

The safety and efficacy of zonisamide (ZNS), a new antiepileptic drug, was tested in 167 adult participants who entered a historical-controlled 16-week open label, multicenter study. The median percent reduction from baseline of partial seizures was 51.8% in the fourth month of the study (baseline median = 11.5 sz/month; treatment weeks 13-16 = 5.5 sz/month). Persons completing the efficacy study successfully were eligible for a long-term safety study; 113 entered this study. Adverse effects involved principally the CNS and were similar to those seen with other antiepileptic drugs. Four persons (3.7%) developed kidney stones and were withdrawn from the study 250-477 days after starting ZNS. Because of the high percentage of kidney stones, development of ZNS was stopped in the United States but was continued in Japan.

Cerebral blood flow (CBF) monitoring in intensive care by thermal diffusion.

Continuous monitoring of cortical blood flow (CoBF) in the intensive care unit is possible with thermal diffusion techniques. The normal brain flow limits have been established when electrical activity ceases and when infarction is likely to occur. With continuous monitoring of CoBF one can see immediate changes in flow and approaching these levels may be anticipated. The thermal diffusion system we have employed is based on the thermal conductivity of cortical tissue. As blood flow increases through the tissue, the conduction of energy away from the flow probe allows the sensor to detect changes in flow. This form of monitoring has been carried out in patients with subarachnoid hemorrhage, resection of cerebral mass lesions, severe craniotrauma, and intractable epilepsy. In subarachnoid hemorrhage, vasospasm can be identified and the efficacy of treatment determined with continuous monitoring of CoBF. During resection of mass lesions, increases in blood flow can be readily detected to document the recovery of brain tissue. Continuous monitoring of CoBF in epilepsy patients is now possible with the implantation of subdural electrodes. The increase in blood flow can be documented and it is apparent that a period of elevation of blood flow is quite short. Therefore, this may be helpful in determining when other forms of CBF determination, such as Single Photon Emission Computed Tomographic (SPECT) scanning should be performed. In patients with cranial trauma, different patterns of CoBF changes are apparent. Some patients may develop increased CoBF prior to elevation of intracranial pressure (ICP); other patients demonstrate a drop in CoBF as a response to increased ICP.(ABSTRACT TRUNCATED AT 250 WORDS)

Interictal temporal lobe epileptiform discharges and their relationship to secondarily generalized epilepsy.

In a previous study of epileptic phenomena in 19 patients with partial complex seizures, it was noted that seizures of left temporal lobe origin had a higher incidence of secondary generalization. To evaluate this observation further, we retrospectively reviewed reports of EEGs for evidence of focal interictal epileptiform discharges (FIED) of temporal lobe origin and correlated this finding with seizure type. Of 3,276 EEG reports reviewed, 195 showed FIED. The medical records of these patients were reviewed and 79 had sufficient information therein to enable seizure classification. Of 79 patients, 61 had secondary generalized seizures, 45 with left temporal FIED, 16 with right FIED. Of 79 patients, 18 had partial seizures, 13 with right temporal FIED, 5 with left FIED (p less than 0.001). These findings suggest that seizures of left temporal lobe origin may have a higher incidence of secondary generalization. The significance of this observation and its relevance to medical and surgical treatment of complex partial seizures is discussed.

Temporal lobectomy for partial complex seizures: evaluation, results, and 1-year follow-up.

Twenty-six patients were evaluated for temporal lobectomy. Fourteen underwent initial monitoring with electrodes in the amygdala and hippocampus bilaterally. Twelve had initial monitoring with scalp and sphenoidal electrodes. Four had conclusive localization without depth electrodes. Twenty-three patients underwent lobectomy. At 1-year minimum follow-up, 15 were seizure free. Five had greater than 90% reduction in seizure frequency. Complications of depth electrodes were one hemorrhage and one abscess. One patient developed impaired memory following surgery. Temporal lobectomy is effective in well-selected patients. Depth electrodes localize seizure onset from mesial temporal structures. Scalp and sphenoidal recording may be sufficient in some cases.