Vertebral artery dissection and posterior stroke in a child.

Vertebral artery dissection is a relatively rare disease. Its symptoms and signs can be misleading, making the diagnosis, even with imaging assistance, difficult. We describe an 8-year-old boy in whom a brain tumor was suspected because of neurological signs and findings on computerized tomography of the brain. The differential diagnosis was broadened with further imaging evaluation. Magnetic resonance angiography demonstrated vertebral artery dissection, which was attributed to a trivial trauma the child had experienced 1 week before presentation. During the follow-up period, the child recovered, except for residual right hemianopsia.

Visual pathway tumors and hydrocephalus.

The authors evaluated the impact of hydrocephalus on the clinical picture of children with visual pathway tumor (VPT) with or without neurofibromatosis (NF). Charts of children with VPT treated in the authors' center since 1985 were retrospectively reviewed, and those with hydrocephalus were selected and summarized. Thirty-five children with VPT were found, of whom 20 had NF. Hydrocephalus was found in 4 children with NF (20%) and in 5 without NF (33.3%). In 6 of the children, ventricular dilatation with signs of acute increased intracranial pressure already existed at the time of diagnosis and the hydrocephalus was shunted at this time. In the other 3 children, all with NF, the hydrocephalus resulted from slowly developing aqueductal stenosis, leading in 2 to severe visual acuity deterioration. The results suggest that in children with VPT and NF, hydrocephalus, and especially hydrocephalus resulting from aqueductal stenosis, is more frequent than in the general population of NF patients, and less frequent than in VPT patients without NF. The possibility of the indolent development of hydrocephalus should be borne in mind while following children with NF. The optic nerve, when already involved with a glioma, is more vulnerable to increased pressure. Thus, in children with VPT and NF, any ventricular dilatation should lead to a consideration of early shunting.

Visual pathway tumor: a heterogeneous tumor with a variable clinical course.

The aim of the study was to delineate the clinical characteristics of visual pathway tumor in children without neurofibromatosis-I. The authors reviewed the charts of all patients meeting these criteria (n = 12) who were followed in their center over a 13-year period. In 8 patients the disease was relentlessly progressive, and imaging showed a chiasmatic/hypothalamic, exophytic globular lesion. The remainder had a benign course with long periods of tumor stability; one showed some spontaneous visual improvement. The lesions of the latter subgroup were multilobular, with elongated posterior extension into the optic tract. This differentiation, according to the imaging findings, may have significant therapeutic implications. In the first type, every effort should be made to arrest the disease and decrease the size of the lesion, whereas in the second, despite decreased visual ability, careful observation in the appropriate approach. There are as yet no known biological markers to better delineate these two types of tumor behavior.

Diffuse brain stem gliomas. Are we improving outcome?

We reviewed our experience with diffuse brain stem glioma (dBSG) to evaluate whether any improvement of outcome had occurred in our patients over the years. Of the 24 children referred to our department with suspected dBSG from 1981 to 1997, 5 had a different final diagnosis based on the clinical course. Mean survival in the remainder was 16+/-9.8 months from diagnosis. Survival increased with a longer interval from onset of symptoms to diagnosis (12.9+/-9.0 months with an interval of 1-4 weeks; 19.50+/-10.8 months with a longer interval). Visual symptoms at presentation were associated with a poorer prognosis. Survival was better in the 3- to 5-year age group (at diagnosis). Overall, a trend toward a slight improvement in survival was seen over the years, which we presumptively attribute to the introduction of intensive chemotherapy for these patients. We suggest that chemotherapy may be important in the management of dBSG until a better modality is found.

Pediatric brain stem gliomas: an update.

It has become evident that pediatric brain stem gliomas are a heterogeneous pathology and should be classified according to clinical and radiological criteria. This classification has contributed to better treatment and greatly improved prognosis. Based on a review of the literature, we describe the different types of brain stem astrocytomas reported, which are: cervicomedullary, exophytic, cystic, focal and diffuse. Particular attention is paid to therapeutic modalities. For the first three lesions named the treatment is surgical and oncological therapy should be evaluated only for regrowth of the mass. Focal tumors of the medulla and pons are still treated empirically (surgically and/or with radiotherapy), because a definitive therapeutic protocol has not yet been elaborated; on the other hand it is well established that if the focal mass is in the midbrain this should merely be monitored by means of serial MRI, while radiotherapy should be applied in the event of the tumor's growth. Diffuse gliomas are treated with oncological therapy, and surgery (for biopsy or tumor excision) is not indicated. Five illustrative cases from our department are presented.

Successful chemotherapeutic treatment of diencephalic syndrome with continued tumor presence.

A 7-month-old infant with typical features of diencephalic syndrome (DES) associated with a hypothalamic mass, most probably a glioma, was treated with chemotherapy. The tumor showed clear shrinkage, but after more than 2 years regrowth was noted. During the treatment period the child regained normal growth and became free of symptoms. As radiation therapy, especially at a young age, has significant adverse effects and a neurosurgical approach to the diencephalic region also has the potential to cause significant sequelae, a chemotherapeutic option, when it exists, is preferred. Thus, in an infant in whom a glioma is suspected to be the cause of the DES, based on the clinical picture and the neuroimaging appearance, chemotherapy should be considered the primary therapeutic modality. Even if its effect is temporary, its use is well justified. The most appropriate treatment protocol still needs to be determined.

Dysembryoplastic neuroepithelial tumor: a curable cause of seizures.

Dysembryoplastic neuroepithelial tumor (DNT) was first characterized in 1988 by Daumas-Duport and Scheithauer [1], who described 39 cases in children with morphologically distinct brain tumors. Partial complex seizures (PCSs), well-defined neuroimages, and typical pathologic findings were characteristic. Surgical resection of the tumor was usually curative. We present a new case of a child with PCSs who was diagnosed and treated for DNT. The clinical presentation and the difficulties of the differential diagnosis are discussed.

Dermoids of the posterior fossa. Case reports and review.

Three children are presented with dermoid cysts of the posterior fossa, one of the most common locations of dermoid. They were initially diagnosed as having abscesses. Clinical presentations included hydrocephalus and recurrent meningitis. A helpful clue for identification is a bony defect of the skull on plain film or on a bone-window at Computed Tomography (CT).

Cord compression as the presenting symptom of extradural malignant lymphoma.

Six patients with spinal cord compression as the presenting symptom of malignant lymphoma are described. These patients suffered from back pain for several months and were diagnosed after sudden paraparesis appeared. Five patients were treated by operative decompression followed by local irradiation, and all regained their motor function. A sixth patient presented with a more insidious paraparesis. A bone marrow aspiration established the diagnosis of malignant lymphoma, and this patient recovered with radiation and steroids alone. Thus, we recommend considering malignant lymphoma as a possible cause of acute cord compression, attempting to establish the diagnosis on an emergency basis within several hours, and attempting to achieve decompression with local radiotherapy and intravenous dexamethasone.

Central neurogenic hyperventilation in a patient with medulloblastoma.

Central neurogenic hyperventilation is a rare but important cause of the frequently observed phenomenon of hyperventilation. Its diagnosis demands that primary respiratory or metabolic causes, as well as cerebrospinal fluid abnormalities, be ruled out. We hereby describe a patient whose attacks of hyperventilation were the presenting sign of her disease and might be consistent with the central neurogenic mechanism. This patient suffered from a medulloblastoma which compressed the pons. After removal of the tumor the hyperventilation attacks ceased.

Conus ganglioglioma in a 2 1/2-year-old boy. Case report.

Gangliogliomas are rare tumors, primarily seen in patients under the age of 30 years. They occur least commonly in the spinal cord. This report presents a 2 1/2-year-old boy who harbored an intramedullary conus tumor with the light microscopic appearance of a ganglioglioma. The neurobiological behavior of this tumor is yet to be determined.