A reappraisal of rhythmic coma patterns in children

OBJECTIVE: This study was designed to determine the prevalence of rhythmic coma patterns in comatose children and to ascertain the prognostic significance of reactive rhythmic coma patterns. METHODS: We retrospectively analyzed and classified electroencephalogram (EEGs) in comatose children between two months and 18 years of age during the period 1996 - 2003 according to modified Young's classification. Outcome at one-year was scored according to the Paediatric Cerebral and Overall Performance Category Scale. Outcomes were compared using Fisher's exact test and Mann-Whitney test. RESULTS: Analysis of 63 electroencephalogram (EEG) records in 38 patients showed rhythmic patterns in 19 records (30.2%; 9 alpha, 4 spindle, 4 theta and 2 beta coma patterns, total number of children = 14). Aetiology and outcome of alpha coma patterns and other rhythmic coma patterns were similar. In five children, one type of rhythmic pattern changed to another. Records with reactive rhythmic coma 66.7% (6/9), were associated with favourable outcome. Sixty percent of the records (6/10 records in seven children) with non-reactive pattern were associated with unfavourable outcome. This clinically significant difference did not reach statistical significance (lower Paediatric Cerebral and Overall Performance Category Scale score p= 0.14; favourable outcome p=0. 19). CONCLUSION: Rhythmic coma patterns in comatose children are not uncommon. Aetiology, reactivity and outcome of individual patterns are similar and thus make the rhythmic coma patterns distinct EEG signatures in comatose children. There was a clinically significant better outcome with reactive rhythmic coma patterns.     

Electrographic status epilepticus in fatal anoxic coma

Electrographic status epilepticus in the absence of conspicuous somatic motor manifestations is described in 10 patients who were comatose following anoxic-ischemic brain damage. The outcome was unfavorable and the response to anticonvulsant drugs was poor. We describe a clinical sign predictive of the electroencephalographic findings, namely brisk, small-amplitude, mainly vertical eye movements readily detectable by passively elevating the lids. However, similar eye movements may infrequently be found in patients whose electroencephalograms show abnormal spike discharges without the occurrence of electrographic status epilepticus following cerebral anoxia, as in 2 other patients we describe.     

The role of evoked potentials in anoxic-ischemic coma and severe brain trauma.

The early recognition of comatose patients with a hopeless prognosis-regardless of how aggressively they are managed-is of utmost importance. Median somatosensory evoked potentials supplement and enhance neurologic examination findings in anoxic-ischemic coma and severe brain trauma, and are useful as an early guide to outcome. The key finding is that bilateral absence of cortical evoked potentials, generated by thalamocortical tracts, reliably predicts unfavorable outcome in comatose patients after cardiac arrest, and correlates strongly with death or persistent vegetative state in severe brain trauma. The author studied 50 comatose patients with preserved brainstem function after cardiac arrest. All 23 patients with bilateral absence of cortical evoked potentials died without awakening. Neuropathologic study in seven patients disclosed widespread ischemic changes or frank cortical laminar necrosis. The remaining 27 patients with normal or delayed central conduction times had an uncertain prognosis because some died without awakening or entered a persistent vegetative state. The majority of patients with normal central conduction times had a good outcome, whereas a delay in central conduction times increased the likelihood of neurologic deficit or death. This report includes a systematic review of the literature concerning adults in anoxic-ischemic coma and severe brain trauma, in which somatosensory evoked potentials were used as an early guide to predict clinical outcome. Greater use of somatosensory evoked potentials in anoxic-ischemic coma and severe brain trauma would identify those patients unlikely to recover and would avoid costly medical care that is to no avail.     

External ophthalmoplegia, alpha and spindle coma in imipramine overdose: case report and review of the literature

A 13-year-old boy with imipramine overdose developed seizures, respiratory arrest, and coma. Abnormalities of oculovestibular reflexes, electroencephalograms, and brainstem auditory evoked potentials were monitored in relation to measurements of drug levels. An alpha-coma electroencephalographic pattern evolved into one evidencing spindle coma and eventually into a normal pattern. Prolonged brainstem auditory evoked potentials also normalized as coma and oculocephalic reflex abnormalities resolved. In spite of the history that suggested hypoxic damage, the absence of reflex eye movements in a comatose patient and the presence of alpha- and spindle-coma electroencephalographic patterns, even with prolonged brainstem auditory evoked potentials, are not reliable prognostic indicators in tricyclic drug overdose.     

影响颅内多发囊性动脉瘤预后的相关因素分析

目的 探讨影响颅内多发囊性动脉瘤预后的相关因素.方法 回顾分析我科2008年1月到2009年12月间的35例颅内多发动脉瘤患者的完整资料,根据患者具体情况,按实施治疗方案分手术、介入、手术加介入三组.术前患者评估内容包括:年龄、性别、动脉瘤数量、部位、侧别、大小、Hunt-Hess分级、Fisher分级.术后评估则以出院时GOS术后评分为准.单因素分析术前各因素、治疗方案对治疗效果的影响,多因素Logistic多元回归分析治疗效果与术前各因素、治疗方案的关系.结果 按GOS术后评分良好(4～5分)24例,差(1～2)11例.三组治疗效果比较差异没有统计学意义.通过统计学单因素分析,显示患者年龄、术前Hunt-Hess分级和Fisher分级与预后具有显著相关性(P＜0.30,参考相关文献).而多因素的Logistic多元回归分析结果显示患者年龄、术前Hunt-Hess 分级和Fisher分级有没有显著相关性(P＞0.05).结论 患者年龄、术前Hunt-Hess分级和Fisher分级是影响颅内多发动脉瘤患者术后疗效的关键因素,合理的治疗方案是提高颅内多发囊性动脉瘤疗效的关键.     

Predictors for cognitive impairment one year after surgery for aneurysmal subarachnoid hemorrhage

OBJECTIVE: To assess predictors for cognitive impairment one year after spontaneous subarachnoid hemorrhage (SAH). Evaluated predictors were the total amount of cisternal blood seen on computed tomography (CT) in the acute phase as measured by the Fisher grade, neurological grade at admission classified according to the Hunt and Hess scale, aneurysm site and patient's age, gender and education level. METHOD: 44 patients were operated by surgical clipping within 72 hours after CT verified aneurysmal SAH. After twelve months the remaining 42 patients were assessed by neuropsychological test, Beck Depression Inventory (BDI), the Glasgow Outcome Scale (GOS) and CT. Multiple regression analysis was conducted where predictor variables were independent factors and a global impairment index calculated for each patient was the dependent factor. RESULTS: The Fisher grade was the only independent predictor for neuropsychological impairment. Most patients had good neurological outcome as measured by the GOS and at the same time suffered from some degree of cognitive impairment at follow-up. Individual analysis of cognitive test scores showed mild to moderate dysfunction across multiple cognitive domains. Most frequent impairments were found in domains of memory, executive function and speed of information processing. Age below 50 years was associated with relatively better outcome. CONCLUSION: The severity of cognitive impairment one year post SAH is predicted by the volume of blood in the subarachnoid space as measured by the Fisher score.     

颅内多发动脉瘤外科治疗的临床研究

目的研究颅内多发动脉瘤外科治疗的临床特点。方法回顾分析63例颅内多发动脉瘤病人的临床资料,将出院时的GOS评分作为预后良好（4—5级）,差（1—3级）,分别评价了年龄、性别、治疗手段、术前Hunt—Hess分级、Fisher分级、动脉瘤部位、侧别、大小、数量等因素的影响。结果GOS评分预后良好49例,差14例。单因素分析显示术前Hunt—Hess分级和Fisher分级与预后相关（P〈0．05）。多因素的Logistic回归分析结果显示各因素与预后均无明显相关（P〉0．05）。结论术前Hunt—Hess分级和Fisher分级会影响颅内多发动脉瘤病人的疗效,治疗方案的选择会提高其疗效。手术和介入的治疗效果未见明显差异。     

Failure of electroencephalography to diagnose brain death in comatose children.

Two isoelectric electroencephalograms obtained 24 hours apart support a clinical diagnosis of brain death in prolonged coma. Without documentation of electrocerebral silence, physicians are reluctant to discontinue vital support systems. A radionuclide bolus technique has been developed that documents the absence of cerebral blood flow in suspected brain death and supplements the flat EEG. In a recent review of this technique, all 27 adults who had EEG activity maintained the integrity of their cerebral blood flow. This contrasts to our studies of 5 children, all of whom demonstrated persistent EEG activity but had no evidence of cerebral blood flow by either the isotope bolus technique (5 patients) or cerebral angiography (4 patients). These children (mean age, 7 months) lacked cephalic reflexes and were maintained on assisted ventilation for an average of 15 days. Multiple electroencephalographic tracings persistently demonstrated low-voltage cortical activity over this time. Despite the lack of cerebral blood flow, all patients were continued on respiratory support. At autopsy, extensive brain liquefaction necrosis was noted. In comatose children, EEG monitoring may be of limited value while cerebral blood flow measurements can provide more practical and prognostic information.     

Evoked potentials in comatose children: auditory brainstem responses

Auditory brainstem responses (ABRs) were studied retrospectively in 80 children (ages 4 days to 19 years) with coma of various etiologies to determine their value as a predictor of outcome. The ABRs performed shortly after admission were analyzed with respect to initial neurologic status and final outcome. Of the 49 patients with initial Glasgow Coma Scale scores of less than 7, only 21 had severely abnormal ABRs. Eighteen had normal ABRs. Of these 18 patients, 10 died, and 8 were neurologically abnormal. Prolonged interpeak latencies were seen in 16 patients who experienced a range of clinical severity. Of the total of 17 children with absent ABRs or only the presence of waves I/III, three children survived, two with minimal neurologic abnormalities and one in a vegetative state. The efficacy of ABRs in comatose children as an early prognostic indicator was not confirmed by this study.     

Apolipoprotein E genotype and traumatic brain injury in children—association with neurological outcome

Objective To determine whether the presence of Apolipoprotein E ε4 genotype (ApoE ε4) is associated with outcomes of traumatic brain injury in children. Materials and methods The ApoE genotype was examined in the group of 70 pediatric patients who suffered from traumatic brain injury. The group consists of 48 boys and 22 girls, and the most frequent was the E3 isoform of ApoE. Polymerase chain reaction/restriction fragment length polymorphism method was used for the ApoE genotype assessment. The severity of trauma was assessed by Glasgow Coma Scale and graded into three categories. The presence of focal neurology signs, comparing the admission and dimission status, and duration of hospital care were observed. The neurological outcome after 1 year was assessed by Glasgow Outcome Scale. Trauma severity was compared with the neurological outcome, according to different ApoE genotypes. For statistical processing, t test, nonparametric Wilcoxon test, Fisher, and χ ² tests were used. Conclusion Our results suggest the association between the ApoE genotype and outcome of traumatic brain injury in children. Patients with ApoE ε4 genotype were more likely to have severe clinical symptomatology and unfavorable neurological outcome after traumatic brain injury compared to significantly better outcome with other ApoE genotype.     

Electroencephalograms of children with permanent cortical visual impairment

The electroencephalograms of 40 children with permanent cortical visual impairment (CVI) were studied. CVI was diagnosed in the presence of severe visual loss, normal or minimal ocular findings and clinical, electrodiagnostic and CT evidence of postgeniculate lesions involving the visual cortex. All patients had a multidisciplinary evaluation, including extensive neurological and ophthalmological investigations. The records did not contain any specific features which would be diagnostic of CVI. Isolated occipital spikes were rare and more commonly multifocal EEG disturbance was seen because of diffuse cerebral involvement. Photic stimulation was of little use in the diagnosis. Multihandicapped children with profound CVI tended to show multifocal abnormalities, no alpha rhythm and a suppressed posterior waking background in their EEGs, whereas those with more residual vision usually had an alpha rhythm. The presence or absence of alpha rhythm seemed to reflect the intactness of the striate cortex. However, the lack of alpha rhythm was not always associated with total blindness and not all children with useful residual vision had alpha rhythm.     

Autism and epilepsy: cause, consequence, comorbidity, or coincidence?

Autism is associated with epilepsy in early childhood, with evidence suggesting that individuals with both autism and more severe cognitive impairment are at higher risk. However, the incidence of an abnormal electroencephalogram and/or epilepsy in the full range of pervasive developmental disorders (PDDs) is not well defined. This naturalistic study addresses the incidence of epilepsy and electroencephalographic abnormalities in children with PDDs. The clinical history and electroencephalograms of 56 children diagnosed with PDD-not otherwise specified, autism, or Asperger syndrome were retrospectively reviewed. Forty percent of children with autism were diagnosed with epilepsy. Abnormal electroencephalograms and epilepsy occurred at significantly higher rates in children in the more impaired range of the autism spectrum (P<0.05). These findings suggest that the use of neurological investigative techniques such as electroencephalography should be a consequence of careful clinical evaluation and should be considered routinely during evaluation of more impaired individuals.     

Endovascular therapy of acute vertebrobasilar occlusion: early treatment onset as the most important factor

In view of the poor prognosis for patients with acute intracranial vertebrobasilar occlusion (VBO), factors were sought that predict survival and good neurologic outcome after acute endovascular treatment by means of local intra-arterial fibrinolysis (LIF) and percutaneous transluminal angioplasty (PTA). LIF was performed in 83 patients with angiographically established acute VBO. A significant residual stenosis after LIF was treated by additional PTA in 8 patients. The types of occlusion were classified as either embolic occlusion (EO) or atherothrombotic occlusion (AO). Outcome was evaluated after 3 months by the Barthel Index (BI) as favorable (BI >90), unfavorable (BI <90) or death and compared for each of 3 diagnostic or treatment variables: recanalization success, occlusion type and time to treatment. Four fibrinolytic treatment modes [urokinase, low-dose and high-dose recombinant tissue-type plasminogen activator (rt-PA), rt-PA + Lys-plasminogen] were also analyzed. The outcome was favorable in 19 patients (23%), unfavorable in 14 (17%) and 50 died (60%). Recanalization was successful in 54 patients (66%). The neurologic outcome was better in recanalized than in nonrecanalized patients (favorable outcome: 30 vs. 10%, mortality: 54 vs. 72%; p = 0.118). The neurologic outcome was better in EO than in AO (favorable outcome: 31 vs. 17%, mortality: 47 vs. 70%, p = 0.112). Under combined treatment by LIF and PTA in 8 patients with AO, 4 survived, 3 with a favorable outcome (38%). Early treatment onset (6 h; favorable outcome: 36 vs. 7%, mortality: 52 vs. 70%, p = 0.005). Although no statistically significant differences were found between the types of fibrinolytic agents, treatment with rt-PA and Lys-plasminogen tended toward better results. Early treatment onset proved to be the most important factor for successful endovascular therapy in acute VBO, whereas recanalization and presence of an embolic occlusion also tended toward better results. Additional PTA may be a promising therapy in cases of significant residual stenosis after LIF.     

Rhythmic coma in children

We describe a syndrome of rhythmic coma in children that consists of an invariant, nonreactive, diffuse cortical activity of a specific frequency, such as alpha, beta, spindle, or theta, recorded from a comatose child. We report 11 cases of children who were found to be in rhythmic coma during their acute illnesses. Their ages ranged from 2 to 15 years, and their diagnoses included encephalitis, head trauma, seizures, near drowning, brain tumors, stroke, and metabolic derangements. The specific frequency of the electroencephalographic pattern, ie, alpha, beta, spindle, or theta, did not influence the outcome. The clinical outcome appeared to depend on the primary disease process rather than the electroencephalographic finding. The prognosis of alpha-frequency rhythmic coma as well as of rhythmic coma in general was better in children than in adults. The pathophysiology in children may be similar, ie, the interruption of reticulothalamocortical pathways by metabolic or structural abnormalities, but the expression of this deafferentation may be more varied in the developing brain. Thus, we propose the term rhythmic coma as a unified concept for alpha, beta, spindle, and theta coma in children.     

Adolescent pertussis-induced partial arousal parasomnia

The aim of the study was to assess neurologic complications of pertussis infection. A file review of all children (age 7-18 years) in our hospital with serology-positive pertussis infection admitted from 1995 to 2005 yielded six patients with neurologic symptoms in whom electroencephalographic studies were performed. Data were collected on their clinical symptoms, electroencephalographic findings, final diagnosis, and outcome. The six patients accounted for 10% of all children diagnosed with pertussis during the study period. Their ages ranged from 10 to 15.5 years. All the children were referred by their primary physician because of a suspicion of epilepsy on the basis of parental reports of inefficient attempts to breathe during sleep accompanied by high-pitched sounds and sounds of suffocation, and sleepwalking. The children were amnesic for the episodes. However, findings on electroencephalogram taken during sleep were negative in all cases. The final diagnosis was partial arousal parasomnia. The symptoms of parasomnia disappeared with resolution of the symptoms of the pertussis infection. In conclusion, partial arousal parasomnia may be induced by pertussis infection. Further studies in larger groups are required to confirm this association.     

Electroencephalographic patterns in unresponsive pediatric patients

To study the occurrence and incidence of various electroencephalographic patterns, the electroencephalograms of unresponsive pediatric patients admitted to the intensive care unit were analyzed. The interpreters were unaware of the patients' clinical diagnoses. A total of 178 electroencephalographic studies performed on unresponsive patients were analyzed over a period of 3 years. The mean age of the study patients was 7.9 years. Sixty-six patients were less than 1 year old. The following electroencephalographic patterns were observed: 58 patients (33%) manifested electroencephalographic patterns consistent with nonconvulsive status epilepticus. Of the patients with nonconvulsive status epilepticus, 32 patients (18%) had generalized nonconvulsive status epilepticus and 26 patients (14%) manifested partial nonconvulsive status epilepticus. The remaining 120 patients (67%) manifested diffuse cerebral dysfunction, with the majority having severe diffuse cerebral dysfunction. Only 4 patients (2%) had triphasic waves, suggesting a metabolic encephalopathy. Thirty-six percent of the patients under the age of 1 year had electroencephalographic patterns consistent with nonconvulsive status epilepticus. Nonconvulsive status epilepticus is a relatively common electroencephalographic pattern in unresponsive pediatric patients. Metabolic encephalopathy is uncommon in this patient group.     

Electroclinical characteristics of hemimegalencephaly

Presented here are two long-term follow-up patients with hemimegalencephaly. Patient 1 had Ohtahara’s syndrome, which evolved into West’s syndrome. Patient 2 had localization-related epilepsy, which demonstrated epilepsia partialis continua throughout the clinical course. The patients’ interictal electroencephalograms revealed asymmetric suppression-burst patterns sometime during the clinical course: only during early infancy in patient 1 and until the last follow-up (at 30 years of age) in patient 2. Both patients had moderate mental and motor disturbances with persistence of seizures. Hemiplegia was progressive during early childhood. Aggravation of hemiplegia might be related to frequent seizures and persistent electroencephalographic abnormalities during early childhood. Although asymmetric suppression-burst patterns are considered characteristic electroencephalographic findings in these cases, the duration of their appearance did not have definite prognostic significance.     

Retrospective study of late febrile seizures.

This retrospective study documents the clinical features, electroencephalographic data, and outcome of 50 children with a history of seizures with fever that occurred after 5 years of age. Children with afebrile seizures before the onset of febrile seizures were excluded. Outcome was based on a cross-sectional survey and the follow-up period was 1-13 years. Of the 50 children, 40 had two or fewer febrile seizures after 5 years of age, and febrile seizures did not occur after 10 years of age. Twenty had complex febrile seizures, and 16 had a first-degree relative with febrile seizures. Five developed afebrile seizures, and 18 had educational difficulties. Epileptiform electroencephalographic abnormalities were observed in 22 but were not predictive of later afebrile seizures. Febrile seizures that occur after 5 years of age recur infrequently and cease by 10 years of age. The risk of developing afebrile seizures in this group is small.     

Autism and epilepsy: Cause,consequence, comorbidity,or coincidence?

Autism is associated with epilepsy in early childhood, with evidence suggesting that individuals with both autism and more severe cognitive impairment are at higher risk. However, the incidence of an abnormal electroencephalogram and/or epilepsy in the full range of pervasive developmental disorders (PDDs) is not well defined. This naturalistic study addresses the incidence of epilepsy and electroencephalographic abnormalities in children with PDDs. The clinical history and electroencephalograms of 56 children diagnosed with PDD—not otherwise specified, autism, or Asperger syndrome were retrospectively reviewed. Forty percent of children with autism were diagnosed with epilepsy. Abnormal electroencephalograms and epilepsy occurred at significantly higher rates in children in the more impaired range of the autism spectrum (P < 0.05). These findings suggest that the use of neurological investigative techniques such as electroencephalography should be a consequence of careful clinical evaluation and should be considered routinely during evaluation of more impaired individuals.     

非抽搐性癫痫持续状态五例及文献复习

目的 探讨非抽搐性癫痫持续状态(NCSE)患者的临床表现及持续脑电监测的脑电图(EEG)特征.方法 对自2008年11月至2009年12月北京大学人民医院急诊科收治的5例NCSE患者行持续EEG监测检查,观察其EEG特征及临床表现.结果 5例均出现发作性意识障碍,其中4例出现烦躁、易怒或躁狂,3例表现出精神运动迟滞和遗忘,2例出现言语自动症和失认,1例出现定向障碍.所有患者的EEG均出现广泛性但一侧明显的异常放电.静脉注射地两泮后,3例患者临床症状迅速改善.结论 NCSE并非罕见,持续EEG监测能查出本病,早期诊断,及时治疗可改善患者预后,临床应注意与其他引起意识紊乱的疾病相鉴别.