Brain perfusion in encephalopathic newborns after therapeutic hypothermia

BACKGROUND AND PURPOSE

Cerebral perfusion patterns in neonates with HIE after therapeutic hypothermia have not been well described. The objectives of this study were to compare global and regional perfusion between infants with HIE and neonate controls and to relate measures of cerebral perfusion to brain injury on conventional MR imaging in neonates with HIE.

MATERIALS AND METHODS

Term encephalopathic neonates meeting criteria for hypothermia between June 2011 and January 2012 were enrolled in this prospective observational study. MR imaging-ASL was performed in the second week of life. Comparisons were made with data from neonate controls who underwent the same imaging protocol. NIRS measures of cerebral oxygenation during and immediately after hypothermia were also evaluated in a subset of patients. Secondary analyses were performed to assess cerebral perfusion and oxygenation differences by pattern of injury on qualitative MR imaging interpretation.

RESULTS

We enrolled 18 infants with HIE and 18 control infants. Mean global CBF and regional CBF in the basal ganglia, thalamus, and anterior white matter were higher in cases compared with controls. Infants with HIE with injury on MR imaging, however, had lower CBF (significant in the thalamus) compared with those with normal MR imaging. Decreased FTOE by NIRS further differentiated patients with HIE with injury on MR imaging.

CONCLUSIONS

Disturbed cerebral perfusion is observed in the second week of life in some babies with HIE despite treatment with hypothermia. Infants with HIE with injury on MR imaging have lower regional CBF in the thalamus compared with those without injury, possibly representing pseudonormalization of CBF and low metabolic demand after progression to irreversible brain injury.

New-onset afebrile seizures in infants: role of neuroimaging

OBJECTIVE

To investigate the presenting characteristics of new-onset afebrile seizures in infants (age 1-24 months) and the yield of neuroimaging.

METHODS

Prospective data were obtained from a standardized evaluation and management plan mandated by a critical care pathway. A total of 317 infants presented with new-onset afebrile seizures between 2001 and 2007. EEG was performed on 90.3%, head CT was obtained on 94%, and MRI was obtained on 57.4%.

RESULTS

We found half of the infants had partial features to their seizures, yet evidence for primary generalized seizures was rare. The majority had more than 1 seizure upon presentation. Seizures in this age group tended to be brief, with 44% lasting less than 1 minute. EEG abnormalities were found in half. One-third of CTs were abnormal, with 9% of all CTs requiring acute medical management. Over half of MRIs were abnormal, with cerebral dysgenesis being the most common abnormality (p < 0.05). One-third of normal CTs had a subsequent abnormal MRI-only 1 resulted in altered medical management.

CONCLUSIONS

Infantile seizures are usually brief, but commonly recurrent, and strong consideration should be made for inpatient observation. Acute imaging with CT can alter management in a small but important number of infants. Due to the superior yield, strong consideration for MRI should be given for all infants, as primary generalized seizures are rare, and there is a high rate of cerebral dysgenesis.

Prospective study of new-onset seizures presenting as status epilepticus in childhood

OBJECTIVE

To characterize children with new-onset seizures presenting as status epilepticus at a tertiary care children's hospital.

METHODS

Prospectively collected data were reviewed from a database derived from a mandated critical care pathway. A total of 1,382 patients presented with new-onset seizures between 2001 and 2007.

RESULTS

A total of 144 patients presented in status epilepticus. The average age was 3.4 years. The majority of seizures (72%) lasted between 21 and 60 minutes. The majority of patients had no significant past medical history; one-fourth had a family history of epilepsy. Five (4%) patients with EEGs had electrographic seizures during the study, captured only with prolonged monitoring. The most common etiology was febrile convulsion, followed by cryptogenic. The most common acute symptomatic cause was CNS infection; the most common remote symptomatic cause was cerebral dysgenesis. Combined CT and MRI provided a diagnosis in 30%. CT was helpful in identifying acute vascular lesions and acute edema, whereas MRI was superior in identifying subtle abnormalities and remote symptomatic etiologies such as dysplasia and mesial temporal sclerosis.

CONCLUSIONS

Children who present in status epilepticus that is not a prolonged febrile convulsion should undergo neuroimaging in the initial evaluation. For any child who presents in status epilepticus and has not yet returned to baseline, the possibility of nonconvulsive status epilepticus should be considered. Although CT is often more widely accepted, especially in the urgent setting, strong consideration for MRI should be given when available, due to the superior yield.

Interhemispheric and intrahemispheric language reorganization in complex partial epilepsy

OBJECTIVE

To investigate interhemispheric and intrahemispheric reorganization in patients with localization-related epilepsy.

METHOD

We studied 50 patients with a left hemispheric focus and 20 normal right-handed controls with a 3T echoplanar imaging blood oxygen level dependent functional MRI auditory-based word definition decision task. Data were analyzed using SPM 2. Using region of interest for Broca and Wernicke areas and an asymmetry index (AI), patients were categorized as left language (LL; AI > or = 0.20) or atypical language (AL; AI <0.20) for region. The point maxima activation for normal controls (p <0.05 corrected FDR) was identified in Broca and midtemporal regions and then used as a point of reference for individual point maxima identified at p < 0.001, uncorrected.

RESULTS

Patient groups showed increased frequency of having activation in right homologues. Activation in AL groups occurred in homologous right regions; distances for point maxima activation in homologous regions were the same as point maxima distances in normal control activation in left regions. Distances for LL patient in left regions showed a trend for differences for midtemporal gyrus (6 mm posterior, 3 mm superior) but variability around mean difference distance was significant. There was no effect of age at epilepsy onset, duration, or pathology on activation maxima.

CONCLUSIONS

Right hemisphere language regions in patients with left hemispheric focus are homologues of left hemisphere Broca and broadly defined Wernicke areas. We found little evidence for intrahemispheric reorganization in patients with left hemisphere epilepsy who remain left language dominant by these methods.

Limitations to plasticity of language network reorganization in localization related epilepsy

Neural networks for processing language often are reorganized in patients with epilepsy. However, the extent and location of within and between hemisphere re-organization are not established. We studied 45 patients, all with a left hemisphere seizure focus (mean age 22.8, seizure onset 13.3), and 19 normal controls (mean age 24.8) with an fMRI word definition language paradigm to assess the location of language processing regions. Individual patient SPM maps were compared to the normal group in a voxel-wise comparison; a voxel was considered to be significant if its z-value exceeded mid R:2mid R:. Subsequently, we used principal component analysis with hierarchical clustering of variance patterns from individual difference maps to identify four patient sub-groups. One did not differ from normal controls; one had increased left temporal activation on the margin of regions activated in controls; two others had recruitment in right inferior frontal gyrus, middle frontal gyrus and temporal cortex. Right hemisphere activation in these two groups occurred in homologues of left hemisphere regions that sustained task activation. Our study used novel data driven methods to find evidence for constraints on inter-hemispheric reorganization of language in recruitment of right homologues, and, in a subpopulation of patients, evidence for intra-hemispheric reorganization of language limited to the margins of typical left temporal regional activation. These methods may be applied to investigate both normal and pathological variance in other developmental disorders and cognitive domains.

Atypical language in lesional and nonlesional complex partial epilepsy

OBJECTIVE

We investigated the relationship between partial epilepsy, MRI findings, and atypical language representation.

METHODS

A total of 102 patients (4 to 55 years) with left hemisphere epileptogenic zones were evaluated using three fMRI language tasks obtained at 1.5 or 3T with EPI BOLD techniques: verbal fluency, reading comprehension, and auditory comprehension. fMRI maps were visually interpreted at a standard threshold and rated as left or atypical language.

RESULTS

Atypical language dominance occurred in 30 patients (29%) and varied with MRI type (p < 0.01). Atypical language representation occurred in 36% (13/36) with normal MRI, 21% (6/29) with mesial temporal sclerosis, 14% (4/28) with focal cortical lesions (dysplasia, tumor, vascular malformation), and all (6/6) with a history of stroke. Multivariate logistic regression analysis found handedness, seizure onset, and MRI type accounted for much of the variance in language activation patterns (chi(2) = 24.09, p < 0.01). Atypical language was more prevalent in patients with early seizure onset (43.2%, p < 0.05) and atypical handedness (60%, p < 0.01). None of the three clinical factors were correlated with each other (p > 0.40). Patients with atypical language had lower verbal abilities (F = 6.96, p = 0.01) and a trend toward lower nonverbal abilities (F = 3.58, p = 0.06). There were no differences in rates of atypical language across time, age groups, or MRI scanner.

CONCLUSION

Early seizure onset and atypical handedness, as well as the location and nature of pathologic substrate, are important factors in language reorganization.

Prognosis of children with partial epilepsy: MRI and serial 18FDG-PET

OBJECTIVE

To study the evolution of cerebral glucose metabolism after partial seizure onset in children, and its relation to clinical variables.

METHODS

Thirty-eight children had 3.4 +/-.8 (18)FDG-PET scans over 3.0 +/- 1.3 years starting within a year after their third unprovoked partial seizure. (18)FDG-PET was analyzed with a region of interest template to measure normalized metabolism in 12 paired anatomic areas. Scans with absolute asymmetry index, |AI|, greater than 0.13 in at least one cortical region other than the cerebellum were considered abnormal. Standard clinical T1- and T2-weighted MRI (1.5 T) scans were obtained.

RESULTS

Patients with initial normal PET (n = 28) were significantly more likely to remain in good seizure control than those with abnormal initial PET. Patients with initially normal PET scans that became abnormal had longer epilepsy duration before the first PET scan, but not greater seizure frequency, than those with PET always normal. There was no evidence for progression of hypometabolism. Patients with shorter time since last seizure and higher seizure frequency were more likely to have abnormal PET scans. Six of the seven patients whose PET scans were always abnormal had poor seizure control. Febrile seizure history did not affect PET findings. MRI was strongly predictive of initial PET results (chi(2) = 13.1; p < 0.02) but did not predict fluctuation hypometabolism. A model combining MRI and initial PET was strongly predictive of clinical course.

CONCLUSIONS

Initial imaging studies can help predict clinical course for children who have had at least three partial seizures. Serial FDG-PET is affected by seizure frequency and time since last seizure.

fMRI language task panel improves determination of language dominance

BACKGROUND

fMRI language tasks reliably identify language areas in presurgical epilepsy patients, but activation using single paradigms may disagree with the intracarotid amobarbital test (IAT).

OBJECTIVE

To determine whether a panel of fMRI tasks targeting different aspects of language processing increases accuracy in determining hemisphere language dominance.

METHODS

Twenty-six patients age 12 to 56 years, predominantly with temporal lobe epilepsy, were studied using whole-brain 1.5 T fMRI (echo planar imaging, blood oxygenation level-dependent) with three task categories using a block design: verbal fluency, reading comprehension, and auditory comprehension. fMRI t maps were visually rated at three thresholds. All patients had assessment of language lateralization by IAT.

RESULTS

fMRI showed left dominance in 21 patients, right dominance in 2, and bilateral activation in 2; raters disagreed over a left vs right bilateral rating in 1 patient. There was full agreement between IAT and fMRI in 21 of 25 patients (IAT failed in 1). In three instances of partial disparity with IAT, the fMRI panel showed consistent findings across raters. Agreement between raters was excellent (partial disagreement in only one patient); the panel of tasks was superior to any single task for interrater agreement (Cramer V 0.93 [range 0.91 to 1.0] vs 0.72 [range 0.60 to 0.86]).

CONCLUSIONS

A panel of fMRI language paradigms may be more accurate for evaluating partial epilepsy patients than a single task. A panel of tasks reduces the likelihood of nondiagnostic findings, improves interrater reliability, and helps confirm language laterality.

Clinical spectrum of succinic semialdehyde dehydrogenase deficiency

Succinic semialdehyde dehydrogenase (SSADH) deficiency is a rare autosomal recessive disorder affecting CNS gamma-aminobutyric acid (GABA) degradation. SSADH, in conjunction with GABA transaminase, converts GABA to succinate. In the absence of SSADH, GABA is converted to 4-OH-butyrate. The presence of 4-OH-butyrate, a highly volatile compound, may be undetected on routine organic acid analysis. Urine organic acid testing was modified at the authors' institution in 1999 to screen for the excretion of 4-OH-butyrate by selective ion monitoring gas chromatography-mass spectrometry in addition to total ion chromatography. Since then, five patients with 4-hydroxybutyric aciduria have been identified. The authors add the clinical, neuroimaging, and EEG findings from a new cohort of patients to 51 patients reported in the literature with clinical details. Ages ranged from 1 to 21 years at diagnosis. Clinical findings include mild-moderate mental retardation, disproportionate language dysfunction, hypotonia, hyporeflexia, autistic behaviors, seizures, and hallucinations. Brain MRI performed in five patients at the authors' institution revealed symmetric increased T2 signal in the globus pallidi. SSADH deficiency is an under-recognized, potentially manageable neurometabolic disorder. Urine organic acid analysis should include a sensitive method for the detection of 4-hydroxybutyrate and should be obtained from patients with mental retardation or neuropsychiatric disturbance of unknown etiology.

Language dominance in partial epilepsy patients identified with an fMRI reading task

BACKGROUND

fMRI language tasks readily identify frontal language areas; temporal activation has been less consistent. No studies have compared clinical visual judgment to quantitative region of interest (ROI) analysis.

OBJECTIVE

To identify temporal language areas in patients with partial epilepsy using a reading paradigm with clinical and ROI interpretation.

METHODS

Thirty patients with temporal lobe epilepsy, aged 8 to 56 years, had 1.5-T fMRI. Patients silently named an object described by a sentence compared to a visual control. Data were analyzed with ROI analysis from t-maps. Regional asymmetry indices (AI) were calculated ([L-R]/[L+R]) and language dominance defined as >0.20. t-Maps were visually rated by three readers at three t thresholds. Twenty-one patients had intracarotid amobarbital test (IAT).

RESULTS

The fMRI reading task provided evidence of language lateralization in 27 of 30 patients with ROI analysis. Twenty-five were left dominant, two right, one bilateral, and two were nondiagnostic; IAT and fMRI agreed in most patients, three had partial agreement, none overtly disagreed. Interrater agreement ranged between 0.77 to 0.82 (Cramer V; p < 0.0001); agreement between visual and ROI reading with IAT was 0.71 to 0.77 (Cramer V; p < 0.0001). Viewing data at lower thresholds added interpretation to 12 patients on visual analysis and 8 with ROI analysis.

CONCLUSIONS

An fMRI reading paradigm can identify language dominance in frontal and temporal areas. Clinical visual interpretation is comparable to quantitative ROI analysis.

Acute identification of cranial burst fracture: comparison between CT and MR imaging findings

BACKGROUND AND PURPOSE

Scalp swelling associated with cranial burst fracture, a widely diastatic skull fracture of infants associated with dural laceration and acute cerebral extrusion, may be confused with that of a simple subgaleal hematoma. Both conditions can also be associated with hemorrhagic shock. We sought to improve the early evaluation of infants believed to have sustained cranial burst fracture by including MR imaging, since this study clearly delineates the dural-cortical interface, the site of injury.

METHODS

Seven infants aged 1 through 11 months who sustained cranial burst fractures, all initially imaged with skull radiography and CT, were studied or treated from 1992 through 1996. MR imaging was obtained after resuscitation and stabilization.

RESULTS

Surgery or autopsy confirmed MR findings (dural laceration and extracalvarial cerebral tissue) in all seven infants.

CONCLUSION

MR imaging allows early diagnosis of skull fracture associated with acute cerebral extrusion.

Spontaneous regression of low-grade astrocytomas in childhood

An 8-year-old boy with neurofibromatosis type 1 (NF1) and a biopsy-proven juvenile pilocytic astrocytoma of the hypothalamic/chiasmatic region was followed with serial MRIs over 4 years. Spontaneous tumor regression was followed by progression and biopsy; 6 months later, the tumor regressed again. This bimodal regression is rare, but highlights the variable natural history of low-grade gliomas in children with NF1 and the difficulty in evaluating response of such tumors to therapy.

Neurodevelopmental and neuroimaging correlates in nonsyndromal microcephalic children

This descriptive study examined the relationship between head size, developmental functioning, and neuroimaging findings in children with absolute microcephaly. Subjects, aged 1 to 48 months, were assigned to one of two groups based on occipitofrontal head circumference (OFC). Group A included subjects with an OFC of 2 to 2.99 standard deviations below the mean, and Group B included subjects with an OFC of 3 or more standard deviations below the mean. Brain scan findings for 62% of the subjects were abnormal. Findings included cerebral atrophy, cortical dysplasia, myelination delay, and white matter hypoplasia. Mean scores for developmental measures in Groups A and B were less than 70. Mean developmental scores in the normal imaging group were 70 or greater, whereas developmental scores in the abnormal imaging group were 52 or less. Forty-three percent of the subjects in Group A and 80% of those in Group B had abnormal findings from imaging studies (p = .0394). Subjects with one or more brain abnormalities determined on the basis of magnetic resonance images or computed tomographic scans had significantly lower scores in all developmental areas (p < .05). The authors concluded that abnormal brain images seem to be a better reflection of developmental performance than the degree of microcephaly. J Dev Behav Pediatr 21:12-18, 2000. Index terms: microcephaly, neuroimaging, neurodevelopment.

Imaging and clinical evaluation of isolated atresia of the oval window

BACKGROUND AND PURPOSE

Congenital causes of hearing loss in children commonly are encountered, and imaging aids in diagnosis as well as presurgical evaluation. Atresia of the oval window not associated with atresia of the external auditory canal (EAC) is a rare cause of congenital hearing loss in children. We present the clinical and imaging findings in children with isolated oval-window atresia.

METHODS

Atresia of the oval window was defined as the absence of the structure with the presence of a bony plate superimposed between the vestibule and middle ear. The bony plate is within the expected region of the oval window. Using a computerized database, nine patients with isolated oval-window atresia were found. All had been evaluated with high-resolution computed tomography (HRCT) and all had medical records available for review, including audiogram results. Imaging studies were interpreted by the consensus of two pediatric neuroradiologists.

RESULTS

Atresia of the oval window was documented in all cases using HRCT criteria. The most common anomalies associated with oval-window atresia were inferomedial malposition of the facial nerve (n = 8), malformed incus (n = 6), and displaced stapes (n = 2). Four patients had symmetric bilateral involvement. Hearing tests were not specific, because conductive, sensorineural, and mixed patterns were found.

CONCLUSION

Anomalies of the oval window should be sought in all patients with congenital hearing loss. Associated findings, such as facial nerve aberrancy and ossicular anomalies, are important in both diagnosis and surgical planning.

Stroke after zoster ophthalmicus in a 12-year-old girl with protein C deficiency

A 12-year-old girl who had zoster ophthalmicus 10 months earlier presented with hemiparesis and corresponding basal ganglionic infarction related to middle cerebral artery branch thrombosis ipsilateral to the zoster. Hematologic evaluation disclosed protein C deficiency. This represents the first zoster-associated stroke reported in childhood associated with protein C deficiency, with extension of the latency period between zoster and infarction, previously reported to be 6 months.

Treatment of children with medulloblastomas with reduced-dose craniospinal radiation therapy and adjuvant chemotherapy: A Children's Cancer Group Study

PURPOSE

Medulloblastoma is the most common malignant brain tumor of childhood. After treatment with surgery and radiation therapy, approximately 60% of children with medulloblastoma are alive and free of progressive disease 5 years after diagnosis, but many have significant neurocognitive sequelae. This study was undertaken to determine the feasibility and efficacy of treating children with nondisseminated medulloblastoma with reduced-dose craniospinal radiotherapy plus adjuvant chemotherapy.

PATIENTS AND METHODS

Over a 3-year period, 65 children between 3 and 10 years of age with nondisseminated medulloblastoma were treated with postoperative, reduced-dose craniospinal radiation therapy (23.4 Gy) and 55.8 Gy of local radiation therapy. Adjuvant vincristine chemotherapy was administered during radiotherapy, and lomustine, vincristine, and cisplatin chemotherapy was administered during and after radiation.

RESULTS

Progression-free survival was 86% +/- 4% at 3 years and 79% +/- 7% at 5 years. Sites of relapse for the 14 patients who developed progressive disease included the local tumor site alone in two patients, local tumor site and disseminated disease in nine, and nonprimary sites in three. Brainstem involvement did not adversely affect outcome. Therapy was relatively well tolerated; however, the dose of cisplatin had to be modified in more than 50% of patients before the completion of treatment. One child died of pneumonitis and sepsis during treatment.

CONCLUSION

These overall survival rates compare favorably to those obtained in studies using full-dose radiation therapy alone or radiation therapy plus chemotherapy. The results suggest that reduced-dose craniospinal radiation therapy and adjuvant chemotherapy during and after radiation is a feasible approach for children with nondisseminated medulloblastoma.

Emergency brain computed tomography in children with seizures: who is most likely to benefit?

OBJECTIVE

To determine whether the recently published guidelines on neuroimaging in patients with new-onset seizures are applicable to children.

METHODS

We carried out a retrospective analysis of 107 neurologically normal children (excluding children with simple febrile seizures) who had undergone neuroimaging when they presented to the emergency department with a possible "first seizure."

RESULTS

Eight of the 107 children had nonepileptic events (gastroesophageal reflux, syncopal event, rigor). Of the remaining 99 children, 49 had provoked seizures (complicated febrile seizure, meningo-encephalitis, toxic or metabolic abnormalities), and 50 had unprovoked seizures. A total of 19 children had brain abnormalities identified on computed tomography (CT) scan; 7 received further investigation or intervention as a result of CT scan findings (2 with tumors, 3 with vascular anomalies, 1 with cysticercosis, and 1 with obstructive hydrocephalus). CT scan abnormalities requiring treatment or monitoring were more frequently seen in children with their first unprovoked seizure (P < .01) and in those children whose seizure onset had been focal or who had focal abnormalities identified on postictal neurologic examination (P < .04).

CONCLUSION

In a child, a seizure in the setting of a fever rarely indicates the presence of an unexpected CT scan lesion requiring intervention.

Phase I study of temozolomide in children and adolescents with recurrent solid tumors: a report from the Children's Cancer Group

PURPOSE

The Children's Cancer Group conducted a phase I trial of temozolomide stratified by prior craniospinal irradiation (CSI).

PATIENTS AND METHODS

Children and adolescents with recurrent or progressive cancer were enrolled. Temozolomide was administered orally daily for 5 days, with subsequent courses administered every 21 to 28 days after full hematologic recovery. Dose levels tested included 100, 150, 180, 215, 245, and 260 mg/m2 daily.

RESULTS

Twenty-seven patients on the non-CSI stratum were assessable for hematologic toxicity. During the first three dose levels (100, 150, and 180 mg/m2 daily), only grades 1 and 2 hematologic toxicity occurred. One patient at 215 mg/m2 daily had grade 3 hematologic toxicity. Three of eight patients (38%) treated at 245 to 260 mg/m2 daily had dose-limiting toxicity (DLT), which included both neutropenia and thrombocytopenia. Twenty-two patients on the CSI stratum were assessable for hematologic toxicity. Hematologic DLT occurred in one of six patients (17%) at 100 mg/m2 daily and in two of four patients (50%) at 215 mg/m2 daily. No nonhematologic DLT occurred; nausea and vomiting occurred in more than half of the patients. After two courses of temozolomide, 10 patients had stable disease (SD), and three patients had a partial response (PR), one of whom subsequently had a complete response (CR) that persists through 24 months of follow-up.

CONCLUSION

The maximum-tolerated dose (MTD) of temozolomide for children and adolescents without prior CSI is 215 mg/m2 daily and for those with prior CSI is 180 mg/m2 daily for 5 days, with subsequent courses that begin on day 28. Temozolomide is well tolerated and should undergo phase II testing in children and adolescents.

Treatment of diencephalic syndrome with chemotherapy: growth, tumor response, and long term control

BACKGROUND

The diencephalic syndrome (DS), which is manifested by progressive emaciation and failure to thrive in an apparently alert, cheerful infant, usually is due to a low grade hypothalamic glioma. Treatment with aggressive surgery and/or radiotherapy is variably successful in controlling disease and may result in severe neurologic sequelae. Chemotherapy recently has been shown to be effective in patients with low grade gliomas of childhood, but it is used infrequently in those with DS.

METHODS

The authors evaluated the efficacy of a regimen of carboplatin and vincristine on improving weight, causing tumor shrinkage, and delaying the need for alternative therapies in seven children (ages 9-20 months; median age, 11 months) with DS. Five patients weighed less than the 5th percentile for their age at the start of the study, one weighed within the 10th percentile, and one weighed within the 25th percentile.

RESULTS

At follow-up (range, 6-54 months; median, 28 months), the patients' weights had increased by 66-95% (median, 80%). On magnetic resonance imaging, four patients had a >50% reduction in tumor mass, one had a 25-50% reduction, and two had stable disease. In those patients with radiographic response to treatment, weight gain was accomplished with oral feedings in four of five patients, whereas those with stable disease required nasogastric, nasojejunal, or gastrostomy tube supplementation to maintain weight. Disease progression occurred at a median of 24 months after initiation of chemotherapy, and two patients remained free of progressive disease at last follow-up. Five patients were alive a median of 59 months from diagnosis. The need for radiation or other therapies was delayed in six of seven children. Therapy was tolerated without significant toxicities.

CONCLUSION

The authors conclude that treatment of DS with a carboplatin and vincristine regimen results in demonstrable weight gain, may result in tumor shrinkage, and in some cases, significantly delays the need for alternative therapies.

Relative incidence and alternative approaches for surgical drainage of different types of deep neck abscesses in children

OBJECTIVES

To determine the relative frequency of retropharyngeal abscesses (RPAs) vs lateral pharyngeal abscesses (LPAs) and to analyze alternative approaches for surgical drainage.

DESIGN

Retrospective chart review.

SETTING

Tertiary care children's hospital.

PATIENTS

Seventy pediatric patients who were evaluated, admitted, and treated for presumed deep neck abscesses (RPAs and LPAs) between January 1, 1986, and December 31, 1996.

INTERVENTION

Intravenous antibiotic therapy and surgical drainage.

MAIN OUTCOME MEASURE

Clinical resolution of the abscess.

RESULTS

Fifty-eight patients were evaluated with computed tomographic scan. Thirteen of these patients did not have surgical intervention. Of 12 patients diagnosed as having an isolated RPA, all had intraoral surgical drainage and 9 had evidence of pus at surgery. Twenty-one patients had an isolated LPA. Sixteen of these underwent intraoral drainage and 5 underwent external drainage. Purulence was found at surgery in 14 and 2 patients, respectively. The remaining 12 patients had a combination of RPA and LPA. Eight patients underwent intraoral drainage, and 4 patients required both intraoral and external approaches. Purulence was found at surgery in 5 and 4 patients, respectively. Of the 12 patients who were not evaluated with computed tomographic scan, two thirds were treated prior to 1987. Six of these 12 patients underwent surgical drainage via an intraoral approach, and 4 of the 6 patients had pus. The remaining 6 improved without surgery.

CONCLUSIONS

Most deep neck abscesses in children are located in the retropharyngeal or in the lateral pharyngeal space medial to the great vessels. Therefore, most can be managed successfully with intraoral rather than external drainage. External approaches are better reserved for those abscesses that are lateral to the great vessels or that involve multiple spaces. In this patient population, LPAs were more commonly seen than RPAs.

Pediatric congenital bilateral perisylvian syndrome: clinical and MRI features in 12 patients

In 1926, Foix, Chavany and Marie described an acquired syndrome of fasciopharyngoglossomasticatory diplegia resulting from bilateral infarction of the anterior operculum. Clinical features consisted of facial diplegia, dysarthria, pseudobulbar palsy, mild to severe mental retardation, and seizures. A developmental form, similar in presentation in adults with MRI findings consisting of bilateral perisylvian cortical malformation consistent with polymicrogyria involving the sylvian fissure and opercular cortex, has been recognized; but few pediatric cases of congenital bilateral perisylvian syndrome (CBPS) have been reported. Over the past four years, we have encountered 12 cases of CBPS presenting in childhood. Age ranges were from 1 week to 11 years with a median of 2.25 years; six were less than two years of age. Seven were male and five female. Ten had bilateral perisylvian polymicrogyria on MRI; two had unilateral perisylvian schizencephaly with contralateral perisylvian polymicrogyria. Clinical manifestations included developmental delay in 7; poor palatal function in 5; hypotonia in 4; arthrogryposis in 4; hemiparesis in 3; apnea in 3; paraparesis in 2; micrognathia in 2; pectus excavatum in 2; quadriparesis in 1; and hearing loss in 1. Seizures occurred in seven (58%) and consisted of infantile spasms (n = 1), generalized tonic-clonic (n = 1), complex partial (n = 2), partial motor (n = 2; 1 with secondary generalization), and febrile convulsions (n = 1). CBPS has different manifestations in the pediatric population than in adults. CBPS is more common than previously thought, is recognizable by MRI and should be suspected clinically in any infant or child presenting with oromotor dysfunction/pseudobulbar signs and developmental delay, especially if there are associated congenital malformations. Epilepsy is not a constant feature in the pediatric presentation and is variable in type and severity.

Diagnostic imaging in neuro-oncology

Recent advances in imaging techniques, biologic characterization, and histologic classification have contributed to improving management of children with brain tumors. The overall prognosis of children with brain tumors nevertheless lags behind that of other pediatric oncologic diseases. This article reviews recent developments in tumor imaging.

Treatment of children with newly diagnosed brain stem gliomas with intravenous recombinant beta-interferon and hyperfractionated radiation therapy: a childrens cancer group phase I/II study

BACKGROUND

Prognosis for the majority of children with brain stem gliomas is dismal. In previous studies, recombinant beta-interferon (r beta IF) has been shown to be effective for children with recurrent brain stem gliomas and may also act synergistically with radiotherapy (RT).

METHODS

Thirty-two children with diffuse intrinsic brain stem gliomas were treated with (r beta IF) and 7200 centigray (cGy) of hyperfractionated RT (100 cGy twice-daily fractions) to determine the toxicity of treatment and the tolerance of the brain stem to this regimen, as well as to assess survival. Patients were treated with r beta IF 3 times per week during RT and then for 8 weeks following RT. Initially, a dose escalation trial was performed.

RESULTS

Interferon was initially begun at 12.5 x 10(6) IU/m2 and escalated up to 400 x 10(6) IU/m2. The safe starting dose was determined to be 100 x 10 (6) IU/m2. Due to unacceptable toxicity, the maintenance dose was reduced to 200 x 10 (6) IU/m2. Therapy was relatively well tolerated, although 13 of the patients required dose modifications due to hepatic or hematologic toxicity. Four of the patients had to discontinue treatment due to this toxicity. One patient died while receiving maintenance IF of encephalopathy, seizures, and brain stem dysfunction; believed possibly due to the r beta IF. Thirty of the 32 patients have developed progressive disease. The median time to progression from study entry was five months and the median time to death was 9 months.

CONCLUSIONS

We conclude that r beta IF plus hyperfractionated therapy can be tolerated by children with newly diagnosed brain stem gliomas, although there is occasional dose-limiting hepatic, blood, and central nervous system toxicity. This therapy did not result in a higher rate of disease control.

Cerebrovascular complications of HIV in children

Two uncommon but important cerebrovascular manifestations of human immunodeficiency virus (HIV) infection in children are arteritis with formation of fusiform aneurysms and arterial sclerosis with vascular occlusion. We studied the CT and MR imaging features of HIV in two girls and one boy (9 to 18 years old) and compared them with autopsy findings in two patients. One of the children had findings consistent with small areas of subacute infarction and the other two had fusiform dilatation of the major vessels of the circle of Willis. The ischemic lesions and arteriopathy were confirmed at autopsy. In one patient, an incidental B-cell lymphoma (not visible on the imaging studies) was diagnosed.

'Complicated migraine-like episodes' in children following cranial irradiation and chemotherapy

Neurologic sequelae may occur months to years after cranial irradiation. The site of primary damage is probably the vascular endothelium. Over a 2.8-year period, four children with brain tumors, a mean of 11 years of age at diagnosis (range, 6.5 to 15.5 years), had new onset of severe intermittent unilateral headaches associated with nausea, episodic visual loss, hemiparesis, aphasia, or hemisensory loss. The headaches lasted 2 to 24 hours. All patients had previously received whole-brain (2,400 to 3,600 cGy) and additional local boost (1,800 to 3,100 cGy) cranial irradiation, as well as cisplatin-, lomustine-, and vincristine-containing chemotherapy regimens. Symptoms began 1.2 to 2.8 years after the diagnosis, when all had stable disease and were off treatment. MRI studies were unchanged, and CSF cytology, EEGs, echocardiograms, and magnetic resonance angiograms were normal in all. Cerebral angiograms, performed in three children, were normal but led to severe headaches and neurologic deficits (hemiparesis in one and visual loss in two) that resolved after 24 to 48 hours. Response to antimigraine and antiplatelet medications was variable. We conclude that (1) "complicated migraine-like episodes" may occur in children after cranial irradiation and chemotherapy as a sequela of therapy; (2) these headaches may not be the harbinger of impending strokes, severe intracranial vasculitis, or tumor recurrence; and (3) while cerebral angiography may be useful in differential diagnosis, it may cause transient worsening of symptoms.

Patient with craniosynostosis and marfanoid phenotype (Shprintzen-Goldberg syndrome) and cloverleaf skull

Marfanoid phenotype with craniosynostosis (Shprintzen-Goldberg syndrome) is a rare disorder previously described in only 5 patients. We report on the sixth known patient with this condition. The findings which distinguish our patient from others reported previously are that she was ascertained prenatally as having a cloverleaf skull; this is the first female patient described with this condition. Postnatally, she presented with arachnodactyly, camptodactyly, and clover-leaf skull. Imaging studies of the brain documented microcephaly with malformed brain, hydrocephaly, and hypoplasia of the corpus callosum. She also had choanal atresia and stenosis, a clinical finding previously reported only once, in this disorder.

Encephalopathy with parkinsonian features in children following bone marrow transplantations and high-dose amphotericin B

Encephalopathy, leukoencephalopathy, and secondary parkinsonism occurred in 3 children with refractory leukemia undergoing allogenic bone marrow transplantation (BMT) who were treated with high-dose amphotericin B for pulmonary aspergillosis or sinus aspergillosis that did not involve the nervous system. Treatment included high-dose cytosine arabinoside, cyclophosphamide, and total body irradiation prior to the BMT. The children developed a progressively worsening encephalopathy and parkinsonian features, characterized by resting tremor, cogwheel rigidity, and masklike facies. Neuroimaging studies showed cerebellar, cerebral, and basal ganglia atrophy, as well as frontal and temporal lobe white matter involvement. Two of the 3 patients recovered, although 1 has residual intellectual impairment. The third succumbed to non-central nervous system Epstein-Barr virus-lymphoproliferative disease and had autopsy-confirmed leukoenephalopathy.

Tumoral multiple sclerosis of the cerebellum in a child

We present a case of cerebellar tumoral multiple sclerosis in an 11-year-old girl and emphasize these two features: (1) Tumoral multiple sclerosis can occur within the posterior fossa and should be strongly considered in the differential diagnosis of mass lesions of the posterior fossa when typical white matter lesions are seen on T2-weighted images. (2) Tumoral multiple sclerosis can demonstrate ring enhancement on MR.

Enlarged vestibular aqueduct and sensorineural hearing loss in childhood

OBJECTIVE

To determine if all children with enlarged vestibular aqueducts (EVAs) have development of uniform progressive sensorineural hearing loss (SNHL). To determine whether the size of the EVA correlates with severity, frequencies involved, and stability of SNHL. To determine if the audiologic pattern of SNHL correlates with likelihood of progression of SNHL.

DESIGN

Retrospective study.

SETTING

Children's National Medical Center, Washington, DC, a tertiary care center with a large otologic practice.

PATIENTS

Fifteen children (26 ears) with EVA on computed tomographic scan.

METHODS

History, physical examination, computed tomographic scans, and serial audiograms were reviewed. Factors analyzed included age at diagnosis, audiometric configuration (high tone, midtone, low tone, flat), degree of hearing loss at presentation, length of follow-up, and presence of associated inner ear anomalies.

RESULTS

Nine ears had progressive SNHL, 16 ears had stable SNHL, and 1 ear had profound SNHL. The predominant audiologic configuration was flat. The audiogram configuration does not correlate with progression of SNHL. The size of the vestibular aqueduct does not correlate with the level, type, or progression of SNHL.

CONCLUSION

Our study failed to uncover factors that might be predictive of progression of hearing loss. We conclude that until a better understanding of the natural history and pathophysiologic condition of EVAs is achieved, there is no surgical or other intervention that can be demonstrated as being efficacious.

Staging and surveillance of children with central nervous system neoplasms: recommendations of the Neurology and Tumor Imaging Committees of the Children's Cancer Group

Standardization of the baseline and surveillance evaluation of children with central nervous system (CNS) tumors could contribute to understanding tumor behavior, establishing prognoses, directing treatment, and interpreting multi-institutional cooperative study data. A tumor categorization schedule, based on recognized patterns of CNS tumor behavior involving 'aggressiveness' as assessed by the likelihood for neuraxis dissemination, relative time to progression and pattern of disease recurrence is presented. Included are the most common histologic subtypes of pediatric CNS neoplasms. No attempt has been made to include all histologic subtypes of pediatric CNS neoplasms. Using this categorization as a framework, recommendations are suggested for baseline evaluation at diagnosis and in surveillance.

Pleomorphic xanthoastrocytoma, a distinctive astroglial tumor: neuroradiologic and pathologic features

PURPOSE

To analyze and discuss CT and MR features of pleomorphic xanthoastrocytoma (PXA) and present salient histopathologic features of this distinctive astroglial tumor.

METHOD

CT, MR, and histopathologic studies on seven patients with the histologic diagnosis of PXA were reviewed retrospectively.

RESULTS

All patients were in their first 3 decades of life when first diagnosed and demonstrated peripherally situated supratentorial tumors of varying size involving the superficial cortex and leptomeninges. Five of six cases examined with CT showed areas of mixed attenuation with four demonstrating well-demarcated enhancement. MR demonstrated low or mixed signal intensity on T1-weighted and high or mixed signal intensity on T2-weighted sequences. All five who received gadopentetate dimeglumine showed well-defined enhancement. Three showed cyst formation. Typical histologic features included marked cellular pleomorphism with giant cells, bizarre nuclei, variable cytoplasmic lipidization and positive immunoreactivity for glial fibrillary acidic protein. Necrosis and endothelial-pericytic cell proliferation were absent.

CONCLUSION

PXA has a highly suggestive neuroradiologic and distinctive histopathologic appearance.

Brainstem gliomas

Brainstem gliomas, a relatively common form of childhood brain tumor, are highly resistant to therapy. With computed tomography and magnetic resonance imaging, these lesions can be diagnosed with a high degree of reliability. The indications for surgery are unclear. Focal lesions may be amenable to partial resections. Stereotactic approaches can be used for diffuse lesions, but it has not been shown that the information obtained changes the approach to treatment or outcome. Higher dose radiotherapy has been recently used but has not improved survival for most patients. Patients with brainstem gliomas must be stratified into risk groups, and new means of treatment are needed.

Focal amyloidosis of the head and neck: evaluation with CT and MR imaging

Localized amyloidosis of the head and neck was found retrospectively in the nasopharynx (n = 3) and orbit (n = 1) of four female patients (mean age, 32 years), three of whom had a prior history of antigenic stimulation. In all patients, computed tomography revealed a slightly high absorption and a relatively homogeneous, partially calcified mass. In the one patient who underwent magnetic resonance (MR) imaging, a distinctive loss of signal intensity was seen on the long repetition time/echo time sequence. This enhanced T2 relaxation may be due to (a) static or slowly fluctuating internal magnetic fields arising from adjacent amyloid protons held in relatively fixed positions within the beta-pleated sheet, resulting in quick phase dispersion; (b) chemical exchange and spin-spin interaction with adjacent water protons; and (c) diffusion through differences in diamagnetic susceptibility. This unusual appearance at MR imaging may improve the ability of radiologists to distinguish focal amyloidosis from many other diseases that affect the head and neck.

Abnormal corpus callosum: a sensitive and specific indicator of multiple sclerosis

The authors investigated whether identification of corpus callosal (CC) involvement might increase the specificity of magnetic resonance (MR) imaging in differentiating multiple sclerosis (MS) from other periventricular white matter diseases (PWDs). They prospectively evaluated 42 patients with MS and 127 control patients with other PWDs. Ninety-three percent of the MS patients demonstrated confluent and/or focal lesions involving the callosal-septal interface (CSI). These lesions characteristically involved the inferior aspect of the callosum and radiated from the ventricular surface into the overlying callosum. CSI lesions were optimally demonstrated on sagittal long repetition time (TR)/short echo time (TE) images and frequently (45% of cases) went undetected on axial images. Only 2.4% of the control patients had lesions of the CC. The authors conclude that midsagittal long TR/short TE images are highly sensitive and specific for MS and that callosal involvement in MS is more common than previously reported.

[Current technique of myelography]

Myelography performed with fine needle technique has become virtually innocuous and can be more liberally used in conjunction with CT to produce the CT-myelogram, a product of remarkable diagnostic precision. The authors contention is based on a series of 1,357 consecutive myelograms or CT-myelograms recently performed using exclusively 26-gauge spinal needles.

Dilemmas in the management of childhood brain tumors: brainstem gliomas

Brainstem glioma is a malignant childhood brain tumor for which the 'best' treatment approach has not been defined. Many issues concerning the management of these lesions require clarification, including the following. (1) Can patients be reliably separated into risk groups? (2) Is surgery indicated; if so, for which patients? (3) How effective are new radiotherapy regimens? (4) What other forms of treatment are available? This article will attempt to address these management issues.