Regional brain injury on conventional and diffusion weighted MRI is associated with outcome after pediatric cardiac arrest.

BACKGROUND: To assess regional brain injury on magnetic resonance imaging (MRI) after pediatric cardiac arrest (CA) and to associate regional injury with patient outcome and effects of hypothermia therapy for neuroprotection. METHODS: We performed a retrospective chart review with prospective imaging analysis. Children between 1 week and 17 years of age who had a brain MRI in the first 2 weeks after CA without other acute brain injury between 2002 and 2008 were included. Brain MRI (1.5 T General Electric, Milwaukee, WI, USA) images were analyzed by 2 blinded neuroradiologists with adjudication; images were visually graded. Brain lobes, basal ganglia, thalamus, brain stem, and cerebellum were analyzed using T1, T2, and diffusion-weighted images (DWI). RESULTS: We examined 28 subjects with median age 1.9 years (IQR 0.4-13.0) and 19 (68 %) males. Increased intensity on T2 in the basal ganglia and restricted diffusion in the brain lobes were associated with unfavorable outcome (all P < 0.05). Therapeutic hypothermia had no effect on regional brain injury. Repeat brain MRI was infrequently performed but demonstrated evolution of lesions. CONCLUSION: Children with lesions in the basal ganglia on conventional MRI and brain lobes on DWI within the first 2 weeks after CA represent a group with increased risk of poor outcome. These findings may be important for developing neuroprotective strategies based on regional brain injury and for evaluating response to therapy in interventional clinical trials.

Non-endoscopic removal of radiologically placed percutaneous primary gastrostomy tubes: a new technique.

PURPOSE: To present a new technique for non-endoscopic removal of radiologically inserted primary percutaneous gastrostomy tubes (PGT) and to assess the utility and safety of this technique in the pediatric population. MATERIALS AND METHODS: Over a 9-year period 172 children (80 F, 92 M) mean age 10 years (range 0.29-24 years) underwent removal of radiologically placed PGTs in the Radiology Department. All procedures were performed with conscious sedation. The procedure time ranged from 20 to 45 min (mean 30 min). The procedures were performed electively at > or = 3 14 months for either gastrostomy button placement (70), balloon gastrostomy and jejunostomy placement (55), or G tube removal at termination of enteral feeding (15). RESULTS: PGT disc retrievals were successful performed in 169 of 173 (98%). No technical failures occurred, but five procedures failed due to PGT disc lodgement in gastric wall (four), and gastrocolic fistula (one). One child had a repeat procedure due to premature removal of the primary PGT necessitating replacement. No deaths occurred. PGT discs retrieval was performed at a mean time interval of 14 months from initial PGT insertion (range 3-40 months). CONCLUSION: Non-endoscopic GT disc removal is a quick and safe procedure. It facilitates easy conversion to a gastrostomy button in the radiology setting and avoids the risk of a retained percutaneous gastrostomy tube remnant and intra/transmural migration of discs.

"Push-pull" gastrostomy: a new technique for percutaneous gastrostomy tube insertion in the neonate and young infant.

OBJECTIVE: To evaluate a newly developed method combining antegrade and retrograde techniques for percutaneous gastrostomy tube (PGT) insertion in the neonate and young infant. MATERIALS AND METHODS: From January 1994 to December 2000, 85 children (47 male, 38 female), mean age 4.5 months (range 0.44-9.13 months) underwent PGT insertion using the "push-pull" technique. With the addition, 57 children had a jejunostomy tube placed as well at or within 24 h of the PGT procedure. The mean weight was 3.74 kg, range 1.5-7.0 kg. The indications for the procedure included failure to thrive in 40 patients (25%), static encephalopathy in 21 (25%), neurological/congenital abnormalities in 12 (14%), aspiration in 7 (8%), and cardiac problems in 5 (6%). RESULTS: Eighty-five PGTs were successfully inserted in 85 children. One procedure was initially unsuccessful due to failed conscious sedation and was completed under general anesthesia. Four of 85 patients initially had attempted antegrade placement that failed, and the procedure was successfully completed using the "push-pull" method. One major complication occurred: a gastrocolic fistula at day 5 post-procedure, which was surgically repaired without sequelae. Tube-related problems included; tube dislodgement (n = 1) and procedure-related stomal infection (n = 3). CONCLUSION: The "push-pull" gastrostomy technique is a safe, effective method of percutaneous gastrostomy tube placement in neonates. It facilitates successful placement of the PGT in patients in whom the classic antegrade method is not possible. It has become the procedure of choice in this group.

Percutaneous gastrostomy tube placement in patients with ventriculoperitoneal shunts.

OBJECTIVE: The purpose of this study is to determine the risk of CNS and/or peritoneal infection in children with ventriculoperitoneal shunts in whom a percutaneous gastrostomy tube is placed. MATERIALS AND METHODS: We placed 205 gastrostomy or gastrojejunostomy tubes from January of 1991 to December 1996. Twenty-three patients (10 boys, 13 girls) had ventriculoperitoneal shunts at the time of placement. All shunts were placed at least 1 month prior to placement of the gastrostomy tube. The patients ranged in age from 8 months to 16 years with a mean age of 6 years, 9 months. Patient weight ranged from 2 kg to 60 kg. All 23 children required long-term nutritional support due to severe neurologic impairment. No prophylactic antibiotics were given prior to the procedure. Of the patients, 21/23 had a 14-F Sacks-Vine gastrostomy tube with a fixed terminal retention device inserted, using percutaneous fluoroscopic antegrade technique. Two of the 23 patients had a Ross 14-F Flexi-flo gastrostomy tube which required a retrograde technique due to a small caliber esophagus in these children. RESULTS: All 23 children had technically successful placements of percutaneous gastrostomy (7) or gastrojejunostomy (16) tubes. Of the children, 21/23 (91%) had no complications from the procedure. Two of 23 (9%) patients demonstrated signs of peritonitis after placement of their gastrostomy tubes and subsequently had shunt infections. In both, children CSF culture grew gram-positive cocci. The antegrade technique was used in both children who developed peritonitis. CONCLUSION: Our study indicates children with ventriculoperitoneal shunts who undergo percutaneous gastrostomy are at greater risk for infection and subsequent shunt malfunction. Therefore, we recommend prophylactic antibiotic therapy to cover for skin and oral flora.

Craniocervical junction subarachnoid hemorrhage associated with atlanto-occipital dislocation.

STUDY DESIGN: The sensitivity of plain radiographs for diagnosing traumatic atlanto-occipital dislocation and its association with craniocervical junction subarachnoid hemorrhage was examined in a retrospective review of seven patients. OBJECTIVE: The purpose of this study was to demonstrate the frequency of nondiagnostic plain radiographs and the common association of craniocervical junction subarachnoid hemorrhage in the context of reported cases of atlanto-occipital dislocation to facilitate better recognition of this injury. The use of sagittal reconstructions of computed tomography or sagittal magnetic resonance imaging for diagnosis was evaluated. SUMMARY OF BACKGROUND DATA: Although traumatic atlanto-occipital dislocation is a common cause of motor vehicle fatalities, survival has been more common in the last 16 years. However, the diagnosis was missed on lateral cervical radiographs in 38% of children and 59% of adults; fewer than half were diagnosed subsequently with plain radiography. Moreover, the diagnosis of traumatic atlanto-occipital dislocation often was not considered, because more than half of the survivors had no neurologic abnormality or unilateral deficit. Consequently, more than one third of initially undiagnosed patients experienced neurologic deterioration due to inadequate cervical immobilization. Additional radiographic studies allowing diagnosis were prompted by the neurologic worsening. METHODS: The authors reviewed seven patients treated with traumatic atlanto-occipital dislocation during a 14-year period. Emergency department records were compared with reexamination of initial cervical radiographs to determine the success in diagnosis by means of published methods. The frequency of cranio-cervical junction subarachnoid hemorrhage on computed tomography was determined, and the use of sagittal imaging for subsequent diagnosis was evaluated. RESULTS: In the emergency department, only one patient's condition was diagnosed as atlanto-occipital dislocation. Review of the initial radiographs identified an additional four patients for whom atlanto-occipital dislocation could be diagnosed. Sagittal computed tomography reconstruction or sagittal magnetic resonance imaging identified the remaining two. All but one patient had craniocervical junction subarachnoid hemorrhage. A review of reported cases revealed a common association of craniocervical junction subarachnoid hemorrhage with traumatic atlanto-occipital dislocation but not with traumatic head injury. CONCLUSIONS: The diagnosis of traumatic atlanto-occipital dislocation is often missed in the emergency department, and current methods for evaluating the integrity of the atlanto-occipital joint on cervical radiographs fail to identify all patients with this injury. Although infratentorial subarachnoid hemorrhage is uncommon in traumatic head injury, craniocervical junction subarachnoid hemorrhage is often associated with atlanto-occipital dislocation and should raise the suspicion of severe craniocervical ligamentous injury. Sagittal computed tomography reconstructions or sagittal magnetic resonance imaging can allow for the diagnosis when plain radiography is inconclusive.

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.

Intracranial abnormalities in infants treated with extracorporeal membrane oxygenation: update on sonographic and CT findings.

PURPOSE: To determine the frequency of intracranial lesions in infants treated with extracorporeal membrane oxygenation (ECMO), to evaluate trends in frequency during an 8-year period, and to determine which infants are at highest risk for intracranial injury. METHODS: Daily sonograms were obtained in 386 infants during treatment with ECMO. Cranial CT scans were acquired after decannulation in 286 of 322 survivors. Abnormalities were classified as major or minor and hemorrhagic or nonhemorrhagic. Results were correlated with infant demographic data. RESULTS: Intracranial abnormalities were detected in 203 (52%) of the 386 infants; 73 (19%) hemorrhagic, 86 (22%) nonhemorrhagic, and 44 (11%) combined lesions. Eighty-two lesions (21%) were classified as major. Forty-six (94%) of 49 major hemorrhages were identified at sonography. CT contributed additional information in 73% of neonates with intracranial abnormalities, of which 17 were major lesions not identified at sonography. The frequency of intracranial hemorrhage was increased in infants who were septic or premature or weighed less than 2.5 kg. An increase in time spent on ECMO bypass increased the risk for nonhemorrhagic injury. During an 8-year period, the frequency of hemorrhagic and major nonhemorrhagic lesions remained constant, whereas minor nonhemorrhagic abnormalities increased significantly. CONCLUSION: Infants treated with ECMO continue to be at high risk for cerebrovascular injury. Although daily sonograms are useful in identifying major hemorrhages, follow-up CT scans are crucial for accurate evaluation of intracranial abnormalities.

The role of frameless stereotactic techniques in the treatment of pediatric CNS lesions.

The surgical management of children with deep-seated lesions within the brain and skull base or with superficial lesions within functionally important regions of the brain is often challenging. In order to optimize the functional outcome of an affected child, it is essential not only to adequately treat the offending lesion, but also to minimize injury to the surrounding brain. In this study, we examined the applicability of a video-interactive frameless stereotactic system for intraoperative localization and treatment of a variety of pediatric central nervous system problems, including craniotomy for tumor (n = 14), vascular malformation (n = 3), or cortical resection for intractable epilepsy (n = 4); ventricular puncture for shunt insertion in a patient with slit ventricles (n = 2); transoral odontoid resection (n = 1); cannulation of a brainstem syrinx (n = 1); removal of a foreign body (n = 1); and posterior craniocervical decompression (n = 1). The efficacy of the system was judged on several criteria: (1) the accuracy of the targeting achieved; (2) whether the system facilitated treatment of the lesions of interest; and (3) whether neurologic function was preserved. In general, the accuracy of the system for target localization was within 2-4 mm when rigid head fixation was employed intraoperatively. In such cases, frameless stereotactic guidance was extremely helpful in providing rapid and reliable assistance with operative planning, which facilitated the treatment of a variety of lesions in critical areas of brain with minimal neurologic morbidity. Limitations of this technology and potential solutions to these shortcomings are discussed. We conclude that the application of frameless stereotaxis for intraoperative localization represents a major advance in the treatment of a variety of intracranial processes in children by providing a means for accurately directing the approach to and removal of a targeted lesion while minimizing injury to the surrounding brain.

Holoprosencephaly and septo-optic dysplasia.

Holoprosencephaly is a rare brain anomaly, which may be seen in liveborn neonates, although it is more common in stillbirths and abortions. It may occur alone or as part of a large number of genetic syndromes and associations. It is thought to arise early in embryogenesis (6 weeks), as the prosencephalon is separating into the two hemispheres. It is a complex anomaly with markedly varying degrees of severity. The most severe alobar form affects the entire prosencephalon. The brain shows no evidence of division into two hemispheres. The central thalami and basal ganglia remain undivided and confluent, and there is a large, dorsally located cyst connected to the large single ventricle. These infants usually die shortly after birth. The semilobar form has variable amounts of hemispheric formation with normalization occurring from dorsal to ventral. Some posterior falx, occipital, and temporal horn formation and evidence of a third ventricle are present. It is compatible with life. The lobar form has the most nearly normal appearance. It often exhibits a well-formed ventricular system, absence of the septum pellucidum, a shallow falx, abnormal connection of gray and white matter across the midline, and partially formed frontal lobes. Facial anomalies, especially hypotelorism and midline clefts, generally parallel the brain malformation in severity. Visual and olfactory symptoms plus pituitary abnormalities are often present. Septo-optic dysplasia is a related entity. It has a constellation of symptoms of hypotelorism, severe visual problems, and short stature or other pituitary symptoms. Primary imaging findings include optic nerve hypoplasia and absent septum pellucidum. Septo-optic dysplasia somewhat resembles lobar holoprosencephaly. Septo-optic dysplasia is more common than holoprosencephaly. Isolated absence of the septum pellucidum is also thought to be a mild brain anomaly.

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.

Traumatic atlanto-occipital dislocation in children.

During a 5-year period, 11 children were identified as having traumatic atlanto-occipital dislocation injury on the basis of clinical and radiographic findings. Radiographic criteria including the distance between the tip of the dens and the basion (DB distance), the BC/OA ratio (ratio of the distance between the basion and the posterior arch of C-1 divided by the distance between the opisthion and the anterior arch of C-1; normal ratio, < 1), and the width of the atlanto-occipital joint (normal width, < or = 5 mm) were correlated with clinical presentation and outcome. Normal pediatric values for DB distance were reviewed in a series of 110 lateral cervical spine radiographs. The normal DB distance was 8.3 mm +/- 4.2 (mean +/- 2 standard deviations). All 11 children had DB distances greater than 1.4 cm (mean, 1.7 cm). The BC/OA ratio was greater than 1 in only six patients. Of the 11 children, six died with severe neurologic deficits and five survived with minimal or no neurologic sequela. Without the clinical presentation variable, widened DB distance may be the first abnormality identified to suggest atlanto-occipital injury.

Bilateral basal ganglia lesions: pediatric differential considerations.

Computed tomography (CT) and magnetic resonance (MR) imaging have dramatically improved the ability to visualize the deep gray structures of the basal ganglia (primarily, the caudate nucleus, putamen, and globus pallidus). Any process that alters cerebral metabolism can lead to basal ganglia damage. This article presents the spectrum of disease that may be seen with bilateral basal ganglia abnormalities in the pediatric population. A simplified approach to the differential diagnosis of these entities is based on acute versus chronic conditions and radiologic manifestations. Acute processes include hypoxia, hypoglycemia, carbon monoxide poisoning, hemolytic-uremic syndrome, osmotic myelinolysis, and encephalitis. Chronic conditions include inherited ("inborn errors of metabolism," Huntington disease, and dysmyelinating diseases) or acquired (sequelae of acute disorders) conditions that represent abnormal biochemical or structural processes within the basal ganglia. Elimination of acute causes gives little hope for improvement. Recognition of chronic disorders is important for counseling purposes, since most of these conditions have specific patterns of inheritance.

Resolving MR features in osmotic myelinolysis (central pontine and extrapontine myelinolysis).

Osmotic myelinolysis is a distinctive clinical syndrome with characteristic MR features in the central pons (central pontine myelinolysis) and in other locations (extrapontine myelinolysis). We describe the resolving MR features in an adolescent who has experienced complete neurologic recovery. Regions of involvement manifested increased T2 signal intensity. The extrapontine involvement was noted to resolve earlier with interim-increased T1-weighted signal. The mechanism for the variable appearance of increased T1 signal intensity is discussed.

The primary empty-sella syndrome and diabetes insipidus in a child.

The empty-sella syndrome is uncommon in pediatric patients. Hypothalamic-pituitary dysfunction is common in these patients but involvement of the posterior pituitary gland is very rare. We report a seven-year-old girl with empty-sella syndrome who first developed arginine-vasopressin deficient diabetes insipidus and then anterior pituitary gland deficiency. The empty-sella syndrome should be included among the causes of arginine-vasopressin deficient diabetes insipidus in pediatric patients.

CT and MR evaluation of intracranial involvement in pediatric HIV infection: a clinical-imaging correlation.

PURPOSE: To review the cranial CT and MR examinations of 29 children with perinatally transmitted HIV infection and correlate the imaging findings with clinical and pathologic data. METHODS: 28 children were examined with CT, four with MR. RESULTS: CT abnormalities were seen in 25 children studied (89%), including cerebral atrophy (25 children), basal ganglia calcification (10 children), periventricular frontal white matter calcification (four children), cerebellar calcification (one child), white matter low attenuation areas (two children), intracranial hemorrhage (three children) and cerebral infarction (one child). Intracranial calcifications were only seen in association with cerebral atrophy and were never seen prior to 1 year of age. Calcifications in the periventricular white matter or cerebellum were always associated with basal ganglia calcifications. MR abnormalities were seen in all four children studied; cerebral atrophy (four children), areas of high signal intensity in white matter (four children), loss of normal posterior pituitary high signal intensity (one child). Cerebral atrophy appeared to be a nonspecific finding that was seen in some children in the absence of neurologic signs and symptoms. All children with intracranial calcifications had developmental delay. Intracranial hemorrhage was seen in children with severe thrombocytopenia. Focal intracranial infections were unusual and neoplastic lesions were not found. CONCLUSIONS: Cerebral atrophy, basal ganglia calcifications, and focal white matter lesions were the most common abnormalities seen neuroradiologically in our series of HIV-infected children; cerebral atrophy was a nonspecific finding.

Predictors of survival and characteristics of childhood stroke.

To determine predictors of outcome we reviewed 226 medical records of patients admitted to Children's National Medical Center with the diagnosis of cerebrovascular disease from 1978 to 1988. Ninety-five cases of stroke were identified by either neuroimaging techniques (87), autopsy (7), or clinical examination (1). Causal factors implicated in 89% of the patients included infectious (21%), vascular (18%), hematologic (15%), cardiac (13%) problems, minor trauma (8%) or miscellaneous (14%) causes. Patient outcome (n = 88) included residual impairment in 54%, complete resolution of their initial deficit in 23%, and death in 23%. Among patients with abnormal CT findings (n = 60), a logistic regression model revealed that patients with hemorrhage were at a significant risk (p = 0.0469) for death (odds ratio (OR) = 5.5, 95% confidence interval (CI) 1.2-24.5); those with an altered level of consciousness (stupor or coma) on presentation were also at risk (p = 0.0166; OR = 6.94, CI 1.7-28.5). The sensitivity and specificity of this model were 57% and 93%, respectively. No other clinical, laboratory, or demographic variable analyzed was predictive of outcome.

Posterior fossa intracranial hemorrhage in infants treated with extracorporeal membrane oxygenation: sonographic findings.

Posterior fossa hemorrhage was documented by autopsy in five infants who had been treated with extracorporeal membrane oxygenation over a 5-year-period. In all five cases, the diagnosis was made prospectively by cranial sonography. Sonographic findings were compared with those in a control group of 15 infants with normal posterior fossae at autopsy. The following sonographic abnormalities were exhibited in neonates with posterior fossae hemorrhage: loss of definition of the cerebellum and fourth ventricle on midline sagittal images, heterogeneous cerebellar parenchyma, focal hypoechoic lesions, ventricular dilatation, and tentorial abnormalities. Bright foci inferior to the third ventricle were seen in four neonates in the normal control group. These foci measured 5-10 mm in diameter. One cranial sonogram was falsely interpreted as showing a posterior fossa hemorrhage because of prominent echoes in the interpeduncular cistern. Infants treated with extracorporeal membrane oxygenation are at risk for developing posterior fossa hemorrhage. Awareness of sonographic signs and potential pitfalls in the interpretation of posterior fossa hemorrhage is important for early and accurate recognition of these unusual and sometimes treatable hemorrhages.