Emeritus Faculty - University Medical Line, Neurology & Neurological Sciences
Neurology Service Chief, Lucile Packard Children's Hospital at Stanford (2006 - Present)
Director, Clinical Neurophysiology Laboratory, Lucile Packard Children's Hospital at Stanford (2005 - Present)
Honors & Awards
Lysia Forno Award for Teaching Excellence, Stanford Neurology Residents (2002-2003)
Neurology Clerkship Teaching Award, Stanford Medical Students (2006-2007)
MD, Univ of Oregon Health Sciences (1981)
BA, Columbia (1977)
Current Research and Scholarly Interests
Epilepsy in children and adolescents. Particular interest in clinical neurophysiology (EEG and video EEG), differential diagnosis of seizures in children, and selection of patients who will benefit from epilepsy surger.
Independent Studies (5)
- Directed Reading in Neurology and Neurological Science
NENS 299 (Aut, Win, Spr, Sum)
- Early Clinical Experience in Neurology and Neurological Sciences
NENS 280 (Aut, Win, Spr, Sum)
- Graduate Research
NENS 399 (Aut, Win, Spr, Sum)
- Medical Scholars Research
NENS 370 (Aut, Win, Spr, Sum)
- Undergraduate Research
NENS 199 (Aut, Win, Spr, Sum)
- Directed Reading in Neurology and Neurological Science
Detection of seizure-like movements using a wrist accelerometer
EPILEPSY & BEHAVIOR
2011; 20 (4): 638-641
Caregivers of people with epilepsy are commonly concerned about unwitnessed seizures causing injury and even death. The goal of this study was to determine if a wrist-worn motion detector could detect tonic-clonic seizures. Individuals admitted for continuous video/EEG monitoring wore a wristwatch-size device that was programmed to detect rhythmic movements such as those that occur during tonic-clonic seizures. When such movement was detected, the device sent a Bluetooth signal to a computer that registered the time and duration of the movements. Recorded detections were compared with the routinely recorded video/EEG data. Six of 40 patients had a total of eight tonic-clonic seizures. Seven of the eight seizures were detected. Nonseizure movements were detected 204 times, with opportunity for canceling transmission by the patient. Only one false detection occurred during sleep. In principle, this device should allow caregivers of people with tonic-clonic seizures to be alerted when a seizure occurs.
View details for DOI 10.1016/j.yebeh.2011.01.019
View details for PubMedID 21450533
Epilepsy surgery following brain tumor resection in children Clinical article
JOURNAL OF NEUROSURGERY-PEDIATRICS
2011; 7 (3): 229-234
Intractable epilepsy following successful brain tumor surgery in children may have several underlying causes such as residual tumor, cortical dysplasia, and gliosis. The authors reviewed the cases of children who had previously undergone resection of a brain tumor only to have medically refractory seizures postoperatively.The authors performed a retrospective case review of 9 children who underwent brain tumor surgery 2-13 years before undergoing a second surgery to try and control their seizures.Eight of 9 children had seizures at the time of tumor presentation. Tumor types included ganglioglioma, dysembryoplastic neuroepithelial tumor, pilocytic astrocytoma, oligodendroglioma, ependymoma, and choroid plexus papilloma. All patients achieved a seizure-free interval before intractable seizures recurred. After the second operation, 3 children were seizure free, 1 only had auras, 2 had rare complex partial seizures, and 3 continued to have relatively frequent seizures, although the frequency and severity were reduced. Seven of 9 patients had pathology showing residual tumor.Epilepsy surgery following earlier brain tumor surgery can provide substantial benefit with reduced seizure number and severity. Despite reassuring brain imaging results, residual tumor was present more often than expected in pathological specimens.
View details for DOI 10.3171/2010.12.PEDS10293
View details for Web of Science ID 000287676800004
View details for PubMedID 21361758
Hypnosis-provoked nonepileptic events in children
EPILEPSY & BEHAVIOR
2008; 12 (3): 456-459
The purpose of this study was to describe the use of hypnotic suggestion as a means of precipitating nonepileptic events in children while they are undergoing video electroencephalographic monitoring (VEEG) for differential diagnosis of seizurelike behavior.Nine children aged 8-16 years were referred for VEEG to differentiate between epileptic seizures and nonepileptic events. All subjects underwent psychiatric consultation. Hypnosis was attempted in all subjects to try to provoke typical seizurelike events.In eight of nine patients, their typical seizurelike events were provoked by hypnosis. In all eight children, video and EEG analysis of the provoked events demonstrated them to be nonepileptic. No epileptiform abnormalities were present on interictal EEGs. No epileptic seizures occurred.Hypnosis is a useful and ethical means of provoking psychogenic nonepileptic events in children. Hypnotic suggestion should be considered as a provocative method when possibly psychogenic nonepileptic events have not occurred spontaneously during diagnostic evaluation.
View details for DOI 10.1016/j.yebeh.2007.12.003
View details for Web of Science ID 000254553900014
View details for PubMedID 18249039
Electroencephalography in holoprosencephaly: findings in children without epilepsy
2003; 114 (10): 1908-1917
To evaluate the electroencephalographic characteristics of patients with holoprosencephaly (HPE) without epilepsy.We evaluated the electroencephalograms (EEGs) of 18 children with HPE who lacked a history of seizures. Neuroimaging studies were assessed for severity of HPE and thalamic non-separation and the presence of dorsal cysts and cortical malformations.Hypersynchronous theta activity occurred in 50 and 60% of EEGs during wakefulness or drowsiness/sleep, respectively, and correlated with the grade of thalamic non-separation (p<0.05). Hypersynchronous beta activity during sleep occurred in 41% of EEGs. Posterior amplitude attenuation occurred in 33% of EEGs and correlated with the presence of a dorsal cyst (p=0.0004). Photic driving responses were seen in 50% of the EEGs. If a dorsal cyst was present, the responses were anteriorly displaced. Epileptiform activity was noted in EEGs of 5 patients and did not correlate with the incidence of clinical seizures.Hypersynchronous activity was present frequently in EEGs of HPE patients, possibly attributable to incomplete separation of the thalami and hemispheres. Dorsal cysts were associated with posterior amplitude attenuation and anterior displacement of the photic response. In this selective cohort, the presence of epileptiform activity was not a risk factor for seizures.To date, this is the largest study of EEGs in children diagnosed with HPE without seizures. This study complements our earlier clinical and neuroradiologic studies by providing neurophysiologic data that serves to enhance our understanding of this complex, rare disorder.
View details for DOI 10.1016/S1388-2457(03)00169-X
View details for PubMedID 14499753
Treatment considerations: role of surgery.
Epilepsy & behavior
2002; 3 (6S1): 32-40
Patients with developmental disabilities, including retardation and global developmental delay, are not ideal candidates for epilepsy surgery. Because they have an increased likelihood of diffuse brain dysfunction and multifocal or generalized epileptogenic zones, there is an increased chance that a focal cortical resection will not confer a major improvement in their seizure frequency and severity. There is also increased concern that cortical resection will lead to increase in the patient's disability. However, by applying the basic principles of epilepsy surgery selection (i.e., convergence of multiple lines of localizing evidence) to this population, patients with a reasonable likelihood of good seizure control can be identified. Various means of localizing seizure onset are reviewed, including history and examination, electroencephalography, magnetic resonance imaging, position emission tomography, single-photon-emission tomography, and magnetoencephalography.
View details for PubMedID 12609310
Short duration of benign partial epilepsy in infancy
JOURNAL OF CHILD NEUROLOGY
2002; 17 (6): 440-445
It has previously been reported that benign partial epilepsy in infancy constitutes up to 29% of the epilepsies presenting in the first 2 years of life. To determine the proportion of benign partial epilepsy in our epilepsy population, we retrospectively reviewed 331 patients with greater than two afebrile seizures in the first 2 years of life between 1993 and 2000. Inclusion criteria were (1) partial seizures with or without secondary generalization, (2) normal development, (3) no other neurologic abnormalities, (4) normal interictal electroencephalograms (EEGs), and (5) good response to treatment. Exclusion criteria included seizures that (1) were caused by acute central nervous system insult, (2) occurred only within the first month of life, and (3) lasted longer than 30 minutes. Of 331 patients, 22 (6.6%) fulfilled the criteria with a minimum of 2 years and a mean of 4 years of follow-up off antiepilepsy drug treatment. Six (27%) had complex partial seizures, and 16 (73%) had complex partial seizures with secondary generalization. Neuroimaging studies were normal in all patients. Of the 6 patients with ictal EEGs, 3 had a temporal lobe focus, 1 had an occipital lobe focus, and the remaining 2 had dual foci. Median onset was 4.0 months (range 0.8-9.3). Seizures remitted within 4 months in 20 (91%). Mean duration of seizure persistence was 2.1 months (range 0-8.3) and was longer in treated patients. Median age at last seizure was 6.4 months (range 2-18). Nineteen were treated with antiepilepsy drugs. At last follow-up (mean duration of 52.2 months), all patients were seizure free and off antiepilepsy drugs. Benign partial epilepsy in infancy is an epilepsy syndrome of short duration and is easily recognized using accepted classification criteria. Benign partial epilepsy in infancy appears to be an idiopathic localization-related epilepsy with a favorable prognosis. The incidence in our population is not as common as previously reported. Based on our findings, we suggest weaning of antiepilepsy drugs 6 months after seizure onset.
View details for PubMedID 12174965
Type 1 diabetes mellitus and epilepsia partialis continua in a 6-year-old boy with elevated anti-GAD65 antibodies
2002; 109 (3)
A 6-year-old boy presented with epilepsia partialis continua 6 months after diagnosis of type 1 diabetes. Anti-glutamic acid decarboxylase 65 antibodies were found in his serum and cerebrospinal fluid. Anti-epileptic agents did not improve his seizures. High-dose steroids, plasmapheresis, and intravenous immunoglobulin resulted in decreased anti-glutamic acid decarboxylase 65 antibody levels and resolution of his seizures.
View details for Web of Science ID 000174202800012
View details for PubMedID 11875178
Sedation of children for electroencephalograms
2001; 108 (1): 163-165
Sedation sometimes is necessary to perform an electroencephalogram (EEG) on a child. A dramatic decline in the need to use conscious sedation in our EEG laboratory prompted this review of our sedation experience. The purpose of this review was to determine the incidence of adverse sedation effects and to determine why the need for sedation had declined.All 513 attempts to administer sedation to children who were undergoing EEG studies during a 4-year period were reviewed retrospectively. Parameters studied included type and amount of the sedative agents, need for repeated dosing, successful completion of the EEG, and complications attributed to the sedative.Sedation was attempted in 513 (18%) of 2855 EEGs performed during the 4-year period. Ninety-one percent of the EEGs performed with sedation were completed successfully. Chloral hydrate was the most frequently administered sedative. Complications (transient oxygen desaturation) occurred in 3 children, all of whom had recognized risk factors for airway compromise. The proportion of children who required sedation decreased from 32% to just 2% during that time period.Sedation of children who are undergoing EEG examinations is effective and safe. Complications are infrequent. The need for sedation can be decreased greatly by adequate preparation and by creating a less-threatening, child-friendly environment in which to perform the study.
View details for Web of Science ID 000169571400044
View details for PubMedID 11433070
Evaluation of children for epilepsy surgery
2001; 34 (3): 159-165
There are three main components to the evaluation of children who are candidates for epilepsy surgery: (1) confirmation of the epileptic nature of the seizures, (2) establishing the medical intractability of the child's epilepsy and (3) localization of the epileptogenic zone. Differentiating epileptic from nonepileptic events requires careful review of the history and the electroencephalogram. Electroencephalographic recording of the habitual seizures usually suffices to confirm the epileptic or nonepileptic nature of the events. Medical intractability is established by assuring that antiepileptic medications appropriate for the child's particular epilepsy syndrome have been used and have been titrated to maximum tolerance before being deemed ineffective. Confident localization of the epileptogenic zone requires that multiple findings such as behavior during the seizure, ictal and interictal EEG, and cerebral imaging studies provide data that are convergent with respect to a likely area of seizure onset.
View details for Web of Science ID 000168722900009
View details for PubMedID 11359105
Success of ambulatory EEG in children
Annual Meeting of the American-Epilepsy-Society
LIPPINCOTT WILLIAMS & WILKINS. 2001: 158–61
Continuous ambulatory EEG (AEEG) monitoring is a method used to (1) determine seizure type and location of seizure onset, and (2) to discriminate between epileptic and nonepileptic events. This study was performed to determine how successful AEEG would be in recording seizures when the events were reported to occur at least 3 days per week. AEEGs of children who were patients at Children's Hospital Oakland between December 1993 and June 1997 were reviewed to see why the recordings were performed and to determine whether typical seizures were recorded. Children who had seizurelike events needed to have typical spells 3 days or more per week to justify obtaining AEEG. Most AEEGs were performed to discriminate between epileptic and nonepileptic seizures. A total of 167 children underwent AEEG recording. Ten were recorded to determine whether they were having frequent subtle seizures or frequent interictal epileptiform discharges. The remaining 157 patients had discrete events. A total of 140 children (89%) had their typical spells recorded. A total of 107 of these children (76%) had nonepileptic events. Average duration of recording was 1.9 days. AEEG is very successful in recording children's seizurelike events when parents report events occur at least 3 days per week. The procedure is well tolerated and there are few technical problems that prolong recording time.
View details for Web of Science ID 000169315700006
View details for PubMedID 11435806