Symptomatic spinal epidural collections after lumbar puncture in children.

BACKGROUND AND PURPOSE: Complications from lumbar puncture (LP) include headache; mild puncture-site pain; and, rarely, subdural, epidural, or subarachnoid hemorrhage. In infants, asymptomatic leakage of CSF documented with ultrasound is common. We report the MR imaging findings and clinical course of 25 symptomatic patients with spinal epidural collections after LP. MATERIALS AND METHODS: MR imaging and clinical records of 25 children with new symptoms following LP were retrospectively reviewed. RESULTS: All patients had abnormal dorsal spinal epidural collections. Signal-intensity characteristics of the collections were most commonly isointense to CSF on all pulse sequences. Significant anterior displacement of the dura with effacement of the subarachnoid space was frequently noted. All patients had fluid surrounding small foci of epidural fat, elevating them from their native interspinous fossa, resulting in a "floating" appearance. Eighteen collections involved the thoracic and lumbar spine; 4 involved the thoracic, lumbar, and sacral spine; 2 extended from the lumbar to the cervical level; and 1 was isolated to the lumbar spine. Five patients had follow-up MR imaging showing complete resolution of collections. The size of the collections was not directly related to the number of puncture attempts. Clinical symptoms resolved with time in all patients with conservative management. CONCLUSION: Symptomatic epidural fluid collections after LP are often extensive and may compromise the thecal sac. These collections are not usually the result of a difficult LP and have signal intensity characteristics most consistent with CSF leak rather than hemorrhage. Signs and symptoms typically resolve with time, without treatment and with no serious sequelae.

Discrepancy between neuroimaging findings and clinical phenotype in Alexander disease.

We present a case of infantile-onset Alexander disease (AD) with a novel glial fibrillary acidic protein mutation but without clinical evidence of neurologic deterioration. Brain MRI studies showed typical AD findings and increasing size of frontal cavitations. Serial proton MR spectroscopy demonstrated high levels of myo-inositol and lactic acid and decreasing levels of N-acetylaspartate. The degree of demyelination and the timing of the axonal degeneration may determine phenotypic severity of the disease. Conventional neuroimaging techniques cannot always predict the outcome.

Thoracic tumors in children with neurofibromatosis-1.

Thoracic tumors have been infrequently reported as a complication of neurofibromatosis-1 (NF1). To determine the prevalence and clinical features of thoracic tumors seen in children with NF1, we reviewed medical records and imaging studies for a group of 260 pediatric patients with NF1 followed in a multidisciplinary NF Center. Extrapleural thoracic tumors were seen in nine patients with NF1, corresponding to a prevalence of 3.5% in this hospital-based series of patients. Pathological studies of the tumors demonstrated plexiform neurofibroma in four cases and neurofibrosarcoma in one case. The remaining four cases were suspected to be plexiform neurofibroma based on clinical features but have not been confirmed histologically. Three patients presented with symptoms of chest pain, syncope, or wheezing; six patients were asymptomatic at the time of diagnosis of the tumors. Physical findings frequently found in patients with thoracic tumors were scoliosis (especially focal scoliosis) and visible plexiform neurofibromas of the neck. We conclude that NF1 patients presenting with any of these signs and symptoms should be screened for thoracic tumors with chest X-ray and magnetic resonance imaging as needed. It is unknown whether screening asymptomatic NF1 patients with chest X-rays on a regular basis will result in an improved outcome.

Congenital epulis.

Congenital epulis of the newborn is a rare gingival tumor that occurs along the alveolar ridge. We report the prenatal sonographic and postnatal MR imaging findings in an infant with maxillary and mandibular congenital epulides.

Hypertensive encephalopathy in children.

We present five cases of hypertensive encephalopathy in children, three with MR imaging findings and two with CT findings alone. One of the five patients had MR perfusion imaging, which showed perfusion abnormalities that support the concept of vasodilation as the major contributor to the syndrome. Hypertensive encephalopathy is rarely reported in children, and its true prevalence may be underestimated. Characteristic lesions in the severely hypertensive child should be recognized as manifestations of hypertensive encephalopathy, and subsequent clinical management should focus on treatment of the hypertension and/or its underlying causes.

Air bag-related deaths and serious injuries in children: injury patterns and imaging findings.

BACKGROUND AND PURPOSE: As of November 1, 1997, automotive air-bag deployments occurring in low-speed collisions had resulted in the deaths of 49 children and in the serious injuries of 19 children in the United States. The purpose of this study was to investigate the patterns of injury occurring in this new mechanism of pediatric trauma. METHODS: In search of common patterns of injury, three pediatric radiologists retrospectively evaluated the available autopsy and imaging studies in 11 such cases not previously reported in the medical literature, in addition to three published case studies. RESULTS: The cause of death or serious injury in every case was the direct result of neurologic injury. Injury patterns differed according to the child's age and type of restraint used at the time of collision. Crush injury to the skull predominated in infant victims traveling in rear-facing child safety seats, and both cranial and cervical spine trauma occurred in older children traveling restrained, improperly restrained, or unrestrained in the vehicle's front passenger seat. CONCLUSION: Air-bag systems pose a potentially fatal threat to the front-seat child passenger. This is directly related to the biomechanics at impact placing the child closer to the deploying air bag. An understanding of the biomechanics provides the radiologist insight into the two types of injury patterns observed.

Spinal MR findings in neurofibromatosis types 1 and 2.

PURPOSE: To evaluate the frequency and nature of spinal pathology, the frequency of clinically silent lesions, and the potential benefit of screening spinal MR in neurofibromatosis patients. PATIENTS AND METHODS: 28 neurofibromatosis type-1 (NF-1) patients and nine neurofibromatosis type-2 (NF-2) patients were studied with postcontrast spinal MR imaging. RESULTS: NF-1: One patient had a biopsy-proven low-grade glioma; five patients, intradural, extramedullary masses (N = 23); one patient, extradural masses (N = 2) (neurofibromas); 16 patients had bony abnormalities; and three patients thecal sac abnormalities. NF-2: Five patients demonstrated intramedullary masses (five/eight ependymomas); nine patients, intradural, extramedullary masses (meningiomas, schwannomas); and four patients, bony abnormalities. Eight/10 NF-1 and four/nine NF-2 patients had asymptomatic masses. CONCLUSION: Intradural disease is common, often asymptomatic, and often presents at a young age in NF-1 and NF-2 patients. Because of the propensity to develop significant asymptomatic as well as symptomatic intradural disease, screening of the entire spine with MR is recommended in both NF-1 and NF-2 patients.

MR imaging of metastatic GI adenocarcinoma in brain.

PURPOSE: To investigate an observed preferential T2-shortening effect seen in patients with intracerebral metastases from adenocarcinoma of the GI tract. METHODS: Ten patients with intracerebral metastases from adenocarcinoma of the GI tract were evaluated with MR imaging with CT and histopathologic correlation. RESULTS: Nine of 10 patients demonstrated intracranial masses with decreased signal intensity on T2-weighted images. T1-weighted images showed decreased or isointense signal in all cases. Special histologic staining was performed in four of 10 cases, all of which were positive for increased protein (mucin) with no evidence of blood products or calcium. CONCLUSION: We propose that the observed preferential T2-shortening effect is secondary to slowing of rotational and translational proton motion caused by increased protein concentration in the form of mucin.

Atretic parietal cephaloceles revisited: an enlarging clinical and imaging spectrum?

PURPOSE: We describe imaging features that are clues to the diagnosis of atretic cephaloceles and discuss clinical findings and a possible mechanism by which these lesions develop. METHODS: Eight children (five girls and three boys) ranging in age from 1 day to 3 years 4 months with midline subscalp lesions underwent radiologic examination with CT or MR imaging. In all cases, the lesions were surgically excised and subjected to pathologic examination. Imaging studies and medical records were reviewed retrospectively. RESULTS: Six of eight children had vertical embryonic positioning of the straight sinus with a prominent superior cerebellar cistern. A "spinning-top" configuration of the tentorial incisura, a "cigar-shaped" CSF tract within the interhemispheric fissure, fenestration of the superior sagittal sinus, and "peaking" of the tentorium were associated findings helpful in making this diagnosis. Two of the eight children had findings indistinguishable from focal dermoid, six were developmentally normal, one had mild motor delay, and one died at the age of 3 years. Pathologic examination revealed glial, meningeal (arachnoid), fibrous, and dermal elements. CONCLUSION: Characteristic findings on MR images and CT scans provide clues to the diagnosis of atretic cephalocele. However, even in the presence of abnormal imaging findings, these children may be developmentally normal.

MR imaging of congenital anomalies of the pediatric spine.

Congenital anomalies of the pediatric spine are ideally evaluated with MR imaging. The wide spectrum of pathology in this category of disease is dramatically displaced for both diagnosis and treatment planning for the neurosurgeon. An understanding of embryology and knowledge of the clinical presentation combined with the MR imaging findings allows the radiologist to play a key role in the evaluation of these complex anomalies.

Decreased incidence of intracranial hemorrhage using cephalic jugular venous drainage during neonatal extracorporeal membrane oxygenation.

Intracranial hemorrhage (ICH) remains one of the more common serious complications of extracorporeal membrane oxygenation (ECMO) in neonates. In 1990 this center began routine use of cephalic jugular venous drainage during neonatal ECMO to augment blood return to the ECMO pump and potentially decrease the incidence of ICH by decreasing cerebral venous pressure. Thirty-four ECMO cases utilizing cephalic jugular venous drainage were compared with the previous 34 ECMO cases. The incidence of ICH decreased from 35% (12/34) to 6% (2/34) when neonates without cephalic jugular venous drainage are compared with those being subject to this technique (P < .01). No differences were found between the two groups in gestational age, birth weight, duration of ECMO, survival, platelet counts, activated clotting times, or incidence of other bleeding complications. Cephalic jugular venous drainage during neonatal ECMO appears to be safe and may decrease the incidence of ICH.

Correlation between computed tomography and surgical findings in retropharyngeal inflammatory processes in children.

Retropharyngeal abscess (RPA) in children is a potentially life-threatening process which often requires immediate surgical intervention. Contrast enhanced computed tomography (CT) is utilized frequently to determine abscess versus cellulitis/phlegmon and aids in determining cases needing surgical drainage. The purpose of this retrospective study was to determine the accuracy of CT in distinguishing retropharyngeal abscess from cellulitis in children. The medical records of 32 children from 1989 to 1997 suspected of having a retropharyngeal abscess were reviewed. All patients included in the study underwent a CT scan as well as surgical exploration within 48 h of the scan. Two patients required two surgical procedures (n = 34). A comparison between CT results and operative findings was made to determine the accuracy of CT imaging in confirming the presence of RPA versus cellulitis. Suspected diagnosis of abscess or cellulitis/phlegmon on CT was confirmed at surgery in 25 of 34 cases (73.5%). The false positive rate of CT scan was 11.8% (4/34), while the false negative rate was 14.7% (5/34). Based on our results, CT is accurate in differentiating abscess from cellulitis in 73.5% of cases. Clinical findings, as well as radiologic findings, must be considered together prior to surgical drainage of a suspected retropharyngeal abscess in children.

Aneurysmal bone cyst: report of a case mimicking orbital tumor.

Aneurysmal bone cysts are rare bone tumors which normally affect the vertebral region or long bones. Involvement of facial bones is uncommon. Although nonneoplastic, these lesions are expansile and may cause local destruction of bone and soft tissues. When making the diagnosis, it is imperative to consider the clinical, radiologic, and histologic features of the entity to avoid confusion with other possibly malignant giant cell tumors. We report an unusual case involving the orbit in a 2 1/2-year-old girl.

Brain MRI and proton MRS findings in infants and children with respiratory chain defects.

OBJECTIVE: The aim of this study is to describe neuroimaging patterns in children with respiratory chain (RC) defects using magnetic resonance imaging (MRI) and proton magnetic resonance spectroscopy (MRS) and to assess their role in the diagnostic evaluation. METHOD: Neuroimaging studies of 49 children (newborn to 15 years old) with biochemical evidence of RC defect were reviewed. Patients were divided in 3 groups ("definite" = 24, "probable" = 14, "possible" = 11) according to Modified Adult Criteria for the diagnosis of RC defect. Eighty-one MRI studies were reviewed for deep gray and white matter changes, degree of myelination, cerebral and cerebellar atrophy, and 67 proton MRS studies were assessed for the presence or absence of lactate elevation, as well as NAA/Cr ratio. The findings were compared among the 3 groups with chi-square test. RESULTS: All patients with "pure" myopathy had normal imaging studies. In patients with CNS involvement, significant differences in the frequency of imaging abnormalities among groups were found for deep gray matter (43 %/8 %/0 %; p = 0.01) and for the presence of lactate elevation on proton MRS (81 %/31 %/0 %; p = 0.001). CONCLUSION: Brain MRI and proton MRS abnormalities were observed only in association with clinical CNS involvement. Deep gray matter signal abnormalities on structural imaging and lactate elevation on proton MRS were more frequently observed in the "definite" group and represent neuroimaging markers for RC mitochondriopathy.

Unusual CNS and orbital metastases of neuroblastoma.

Although neuroblastoma is a common childhood malignancy with frequent metastatic disease, involvement of the CNS and eye are unusual findings. Recently, we encountered two such cases. One of the patients had undergone bone marrow transplantation. The long term effects of this treatment regarding behavior of the tumor and subsequent metastatic pattern have yet to be determined. The second patient presented with apparent congenital neuroblastoma. Both of these tumors were extremely aggressive in nature, and could represent variations of the usual metastatic pattern of neuroblastoma.

Posterior perineal hernia presenting in infancy as a gluteal mass.

Perineal hernias are extremely rare at any age but particularly in children. This case illustrates the presentation of a posterior perineal hernia in a newborn infant, with clinical presentation as a gluteal mass.

Unusual CNS presentation of neuroblastoma.

Neuroblastoma is a common tumor of childhood, usually occurring in children under 4 years of age [1]. We report a case of a 10-year old child who initially presented with a large calvarial mass representing a solitary site of metastasis from an occult adrenal neuroblastoma. The sunburst pattern of the calvarial metastasis noted in this case is rarely seen with neuroblastoma. The age of our patient, solitary focus of metastasis at presentation, and imaging appearance of the tumor are very uncommon findings of neuroblastoma.

Primary B-cell lymphoma of the CNS in an infant.

Primary B-cell lymphoma of the CNS is a rare tumor representing 0.2 to 2% of all primary CNS malignancies. The usual age of presentation is in the 4th to 6th decades. Sporadic cases have been reported in the pediatric population. However, even in this age group the tumor is extremely rare under the age of 5. This is a report of a 3-year-old child with primary lymphoma of the CNS.