Trends in American Board of Psychiatry and Neurology specialties and neurologic subspecialties.

OBJECTIVE: To review the current status and recent trends in the American Board of Psychiatry and Neurology (ABPN) specialties and neurologic subspecialties and discuss the implications of those trends for subspecialty viability. METHODS: Data on numbers of residency and fellowship programs and graduates and ABPN certification candidates and diplomates were drawn from several sources, including ABPN records, Web sites of the Accreditation Council for Graduate Medical Education and the American Medical Association, and the annual medical education issues of the Journal of the American Medical Association. RESULTS: About four-fifths of neurology graduates pursue fellowship training. While most recent neurology and child neurology graduates attempt to become certified by the ABPN, many clinical neurophysiologists elect not to do so. There appears to have been little interest in establishing fellowships in neurodevelopmental disabilities. The pass rate for fellowship graduates is equivalent to that for the "grandfathers" in clinical neurophysiology. Lower percentages of clinical neurophysiologists than specialists participate in maintenance of certification, and maintenance of certification pass rates are high. CONCLUSION: The initial enthusiastic interest in training and certification in some of the ABPN neurologic subspecialties appears to have slowed, and the long-term viability of those subspecialties will depend upon the answers to a number of complicated social, economic, and political questions in the new health care era.

Degenerative disorders of the central nervous system.

A child's development generally proceeds along expected pathways, with anticipated levels of function for specific ages. When these levels are not met, the treating physician must determine whether the child has a static or a progressive process. If the child achieves certain levels of development, then loses these skills, the chance is greater that the process is progressive. The technological revolution and progress in molecular genetics in the past 20 to 30 years provide greater avenues for the diagnosis of many of the progressive disorders affecting neurons and central nervous system (CNS) function. Many disorders can be diagnosed in utero, and treatments are available for some. It has become increasingly evident that many of the inherited neurodegenerative disorders have varied clinical phenotypes, and clinical phenotypes may overlap between some of the disorders. This article provides a framework for the primary physician to consider some of these disorders and a rational approach to the evaluation of a child suspected of having a progressive neurodegenerative disorder.

Vagal nerve stimulation in children.

Vagal nerve stimulation is a new therapeutic option for patients with medically refractory epilepsy. The FDA approved the NeuroCybernetic Prosthesis (NCP) in July 1997 for use in adults and adolescents over the age of 12 years with medically refractory epilepsy. Most of the patients in the initial pilot studies and subsequent extended longitudinal and randomized controlled studies were adults. There were small numbers of children who received the NCP system. However, these were not part of controlled studies. As the system has had greater exposure in the United States and Europe, there are more children who are receiving vagal nerve stimulation (VNS). Initial data from open-label, uncontrolled studies suggest that VNS does have some efficacy and safety for those children with refractory epilepsy who have not responded to appropriate trials of antiepileptic drugs. The questions to be asked and answered are as follows: (1) When is a child medically refractory? (2) What are the criteria for selection for VNS? (3) Which seizure types or syndromes will benefit most from the treatment? and (4) What are the most effective and safe stimulation parameters, and do these vary depending on the seizure type?

The ketogenic diet in refractory epilepsy: the experience of Children's Hospital of Pittsburgh.

The ketogenic diet appears to be effective in reducing seizure frequency in patients with epilepsy refractory to antiepileptic drug therapy. Reported seizure frequencies before and after the diet was initiated were obtained for 48 patients started on the ketogenic diet between December 1994 and January 1998 at Children's Hospital of Pittsburgh. The majority of patients (71%) were able to achieve > or = 50% reduction in seizure activity. Of these, more than half (53%) had > 90% reduction in seizures after 45 days of diet therapy. Complications included gastrointestinal complaints and infrequent lipid abnormalities. The ketogenic diet appears to be an effective method of treatment for children with epilepsy refractory to drug therapy.

Planned ictal FDG PET imaging for localization of extratemporal epileptic foci.

PURPOSE: This work demonstrates the feasibility of planned ictal positron emission tomography (PET) with [18F]fluoro-2-deoxy-glucose (FDG) for localization of epileptic activity in patients with frequent partial seizures of extratemporal origin. METHODS: Ictal PET imaging was performed in four patients (two men and two women, ages 28-61) with continuous or very frequent (every 3-15 min) partial seizures. All patients had abnormalities apparent on magnetic resonance (MR) or computed tomographic (CT) imaging, two with extensive brain lesions that precluded precise localization of the seizure focus with interictal PET or single-photon emission tomography (SPECT) imaging. RESULTS: Ictal PET imaging demonstrated a restricted area of focal hypermetabolism concordant with surface electroencephalographic (EEG) recording in all cases. The PET images were registered to MR imaging data for further anatomic localization of hypermetabolic regions in three cases. The ictal PET data were used to guide neurosurgical intervention in one case. CONCLUSIONS: We conclude that planned ictal PET imaging may be a useful and potentially superior approach to ictal SPECT for identifying the epileptic focus in a selected group of patients with continuous or frequent simple partial seizures.

An open-label study of repeated use of diazepam rectal gel (Diastat) for episodes of acute breakthrough seizures and clusters: safety, efficacy, and tolerance. North American Diastat Group.

PURPOSE: To assess safety of diazepam rectal gel (DZPRG) for control of acute seizures in epilepsy patients and to evaluate tolerance with repeated use of DZPRG at intervals of > or =5 days. METHODS: Subjects were persons with epilepsy, age 2 years or older, with seizure clusters or prolonged seizures. Onset of a treatable episode was defined; caregivers were trained to administer DZPRG and to monitor respiration, seizures, and adverse effects (AEs). DZPRG was dispensed in a single-use, prefilled syringe; dosage was determined by age and weight. Maximal use was > or =5-day intervals, < or =5 times/month. After use, caregivers returned data booklets and syringe. Caregivers and physicians completed global ratings yearly. RESULTS: In 149 subjects treated, 77% of 1,578 administrations resulted in seizure freedom for the next 12 h. One hundred twenty-five received two or more treatments (two to 78; median, 8), 0.03-4.3/month (median, 0.4). To evaluate tolerance, subjects with two or more episodes were divided into low (two to seven episodes) and high use (eight to 78 episodes treated). There was no difference in proportion seizure free 12 h after the first administration versus last administration, for either infrequent or frequent administration. Sedation occurred in 17%, attributed to DZPRG in 9%. No respiratory depression was attributable to DZPRG. Three subjects withdrew because of AEs attributable to (agitation) or possibly attributable to DZPRG (chest pain, rash). Five subjects withdrew because of AEs unrelated to DZPRG. Caregiver and physician global ratings were highly positive at both 12 and 24 months. CONCLUSIONS: DZPRG is safe and effective in children and adults with epilepsy with breakthrough seizures. Neither tolerance nor significant medication-related AEs were seen with repeated DZPRG administration at intervals > or =5 days.

Unusual case of inflammatory spinal epidural mass (Castleman syndrome).

Castleman syndrome (giant lymph node hyperplasia) is a rare, heterogeneous lymphoproliferative disorder of unknown etiology and pathogenesis. Most cases occur as mediastinal masses, although extrathoracic involvement including nodal and extranodal locations have been reported. The localized variants (solitary lesions) respond well to surgical excision. We report a 10-year-old boy who presented with headache, intermittent fever, and progressive weakness of his legs. MRI imaging showed an enhancing epidural mass with impingement on the spinal cord at the C6-T2 level. Other laboratory abnormalities included anemia, hypergammaglobulinemia, increased erythrocyte sedimentation rate, and cerebrospinal fluid pleocytosis with slightly increased cerebrospinal protein. The mass was partially resected and the histopathology showed lymphoplasmocytic infiltration compatible with Castleman syndrome. There was no evidence of malignancy. Castleman syndrome is the most likely diagnosis in the presence of the associated systemic findings, although the epidural site for lymphoplasmocytic inflammation is atypical.

Postoperative medical management following pediatric epilepsy surgery.

Medical management of the post-epilepsy surgery patient depends on careful preoperative consideration of that patient's medical, social, cognitive, and emotional status. Outcome expectations should be realistic. Families should be warned that existing cognitive and psychobehavioral problems may not be following surgery, even if seizures are well controlled. As criteria for surgery and surgical techniques continue to evolve, epilepsy centers have an ongoing responsibility to provide objective assessment of outcome. Prospective multicenter studies are required to address these issues adequately.

Ictal midline epileptiform discharges.

Epileptiform discharges arising from the midline (Fz, Cz, Pz) are relatively uncommon. They have been found more frequently in children, are often activated by sleep, and correlate well with clinical seizures. Only a few studies discuss the issue of midline spikes, and all of them deal with interictal activity. We report 8 patients (age range 5 weeks to 17 years) in whom ictal midline discharges were recorded from scalp EEG. The following clinical seizures were recorded: complex partial, simple sensory and myoclonic. The ictal EEG showed spike and spike and slow wave complexes, rhythmic theta, background attenuation, and paroxysmal fast activity. Based on reports of animal experiments and on the variety of types of clinical seizures and their ictal EEG correlates in the patients reported here, it is suggested that the midline scalp EEG discharges do not represent the anatomical focus of origin of the seizures. They probably reflect secondary extension and summation of a remote source of epileptogenic activity.

Epileptic nystagmus.

We report a 52-year-old woman with episodes of vertigo accompanied by right beating nystagmus and left posterior temporoparietal sharp waves and spikes on electroencephalogram without change in level of consciousness. Electrooculography demonstrated that the episodes of nystagmus were not preceded by gaze deviation and that nystagmus slow component velocities were linear. This patient's epileptic nystagmus may have been the result of excitation of cerebral ocular pursuit pathways.

Phenobarbital treatment and major depressive disorder in children with epilepsy: a naturalistic follow-up.

Of an original cohort of 39 epileptic patients, 28 were observed for a median of 26.5 months after an initial psychiatric interview. As had been noted in the original cohort, treatment with phenobarbital, as compared with treatment with carbamazepine or no anticonvulsant, was associated with higher rates of depression (38% vs 0%, P = .04). Depression associated with phenobarbital treatment at intake did not remit spontaneously on follow-up as long as phenobarbital use continued. Those patients treated with phenobarbital who were previously depressed and whose medication was changed to either carbamazepine or no medication showed nonsignificant trends toward declines in both the frequency and severity of depressive symptoms. These results provide further evidence that treatment with phenobarbital increases the risk for depression in epileptic patients and should be avoided when clinically feasible, particularly in patients with a personal or family history of affective disorder. Epileptic patients who receive phenobarbital because of clinical considerations should be monitored closely for symptoms of an affective disorder, and if depression is detected, a change to an alternative anticonvulsant may result in amelioration of depressive symptomatology.

Phenobarbital treatment and major depressive disorder in children with epilepsy.

The prevalence and severity of psychopathology in 15 epileptic patients treated with phenobarbital and 24 patients treated with carbamazepine were compared. The groups were similar across a wide range of demographic, seizure-related, and family-environmental variables. Patients treated with phenobarbital, when compared with those treated with carbamazepine, showed a much higher prevalence of major depressive disorder (40% v 4%, P = .02), and suicidal ideation (47% v 4%, P = .005) as determined by semistructured psychiatric interviews. The differential prevalence of depression between medication groups was only noted in those with a family history of a major affective disorder among first-degree relatives. Family discord and number of stressful life events were also associated with depression in this cohort. Patients treated with phenobarbital should be closely monitored for depression, and alternative treatments should probably be sought for patients with newly diagnoses epilepsy and a personal or family history of an affective disorder. The clinical and research implications of these findings are discussed.

The effect of puberty on the course of epilepsy.

It has been stated that puberty adversely affects epilepsy. In this retrospective study, 39 patients (24 girls and 15 boys) with onset of epilepsy before puberty were followed up for seven years extending from prepuberty into puberty. A general trend toward fewer seizures during puberty was observed, but this trend reached statistical significance for only the female patients after menarche. These changes were not related to treatment. We conclude that, in general, puberty does not influence epilepsy. In the postmenarche phase of puberty, however, female patients might experience a better seizure control.

Outcome in neonates with convulsions treated in an intensive care unit.

Neurological and developmental outcome was assessed in 131 survivors of neonatal seizures aged 1 to 5 years who had been treated in a single intensive care unit from 1976 to 1979. Half the children had been born at less than 37 weeks' gestational age, and 28% at 31 weeks or less. Fifty-one children were normal on examination, 17 had minor abnormalities, 25 had moderate disabilities, 30 had severe disabilities, 6 had died because of profound neurological deficits, and 2 could not be located. Recurrent nonfebrile seizures had developed in 26 children. Most children with motor handicaps or visual loss were intellectually retarded, but 10 of 15 children with bilateral hearing loss were intellectually normal. Of 77 children whose seizures were caused by a hypoxic-ischemic insult, 41 developed moderate or severe disabilities. As determined by multivariate analysis, significant neonatal predictors of poor outcome in this group included seizures with late onset, tonic seizures, and seizures lasting for many days. Although seizure frequency and neonatal mortality associated with seizures were greatest in very premature infants, the outcome in premature infants who survived was not significantly different from that of term infants.

Childhood oligodendrogliomas presenting with seizures and low-density lesions on computed tomography.

Three children with cerebral oligodendrogliomas causing partial complex or generalized seizures presented with completely normal neurologic examinations. CT showed low-density, nonenhancing surface lesions. Although these CT features are usually associated with infarcts or cysts, neoplasm was suspected because of irregularity of the margins and erosion of the adjacent inner table of the skull. Oligodendrogliomas often enlarge slowly and may cause seizures years before they produce focal neurologic signs. CT of all children with seizures not responsive to anticonvulsant medication and focal clinical or EEG abnormalities will hasten diagnosis of slowly growing intracranial mass lesions.

Electroencephalographic changes in pediatric patients following metrizamide cisternography.

Serial electroencephalograms were obtained over a 24-hour period in 15 children from 3 months to 17 years following metrizamide CT cisternography. Persistent EEG abnormalities were noted in 8 children, 5 of whom were older than 2 years. Bifrontal slowing was a frequent change in the children older than 2 years.