Intraorbital and intracranial soft-tissue glomus tumor in an 8-year-old child. Case report

Soft-tissue glomus tumors (or glomangiomas) are unrelated to neuroendocrine paragangliomas (glomus tympanicum, jugulare, and vagale). The authors present the first reported case of an orbital soft-tissue glomus tumor in a child. An 8-year-old girl developed rapidly progressive right-eye blindness, proptosis, and a sixth cranial nerve palsy. Magnetic resonance imaging demonstrated a homogeneously enhancing lesion extending from the right orbit through the superior orbital fissure to the cavernous sinus and middle cranial fossa. A biopsy specimen demonstrated the lesion to be a soft-tissue glomus tumor. Following angiography and embolization, a gross-total resection of the tumor was achieved. The patient was treated with adjuvant proton-beam radiotherapy. At 24 months follow-up her proptosis and sixth cranial nerve palsy had resolved and there was no evidence of tumor recurrence.

Surgical treatment of moyamoya syndrome in patients with sickle cell anemia: outcome following encephaloduroarteriosynangiosis

OBJECTIVES

Children with sickle cell anemia (SCA) and moyamoya syndrome carry a significant risk of ischemic stroke. Given the success of encephaloduroarteriosynangiosis (EDAS) or pial synangiosis in the treatment of moyamoya disease, the purpose of this study was to examine whether it reliably and durably protected children with SCA and moyamoya syndrome against cerebrovascular complications.

METHODS

The authors retrospectively reviewed a series of 12 patients with SCA who developed clinical and/or radiological evidence of moyamoya syndrome and underwent EDAS.

RESULTS

Eleven patients (92%) presented following a cerebrovascular accident (CVA), transient ischemic attack (TIA), or seizure. Magnetic resonance (MR) imaging or angiography suggested moyamoya vascular changes, and cerebral angiography confirmed the diagnosis in all 12 patients. At the time of surgery, the median age was 12.3 years (range 6.8-19.4 years). Ten (83%) of 12 patients had a history of CVA, and 4 of these patients were compliant with a transfusion protocol at the time of their CVA. Bilateral (7 patients) or unilateral (5 patients) EDAS was performed without complications. The mean follow-up period was 46.8 months (range 8.1-106 months). During the follow-up period, 2 patients (16.7%) suffered cerebrovascular events. One patient, who was stroke-free preoperatively, suffered a CVA 3 weeks after the procedure. The other patient suffered a single left lower-extremity TIA 18 months following right-sided EDAS. She returned to her neurological baseline condition and remains stable 53 months postoperatively. Seven patients underwent follow-up angiography or MR angiography, and evidence of revascularization was noted in all cases. At this time, no patient has developed progressive disease requiring a contralateral procedure after unilateral EDAS.

CONCLUSIONS

The EDAS procedure is a safe and effective treatment option in patients with SCA who develop moyamoya syndrome.

Pitfalls for the pediatrician: positional molding or craniosynostosis?

Abnormal head morphology is common among infants and often leads parents to ask their pediatricians for guidance. While the vast majority of such children development and prevent adverse neurobehavioral sequelae secondary to increased intracranial pressure or impaired cerebral growth. The coordination of a multidisciplinary team in the setting of a center experienced in the management of craniosynostosis will assure the best possible results for each patient.

Cerebellar pilocytic astrocytoma with auditory presentation: case study

An 8-year-old girl complained of decreased hearing and difficulty hearing from her right ear while on the telephone. Pure-tone and speech audiometry, immittance (tympanometry, acoustic reflex thresholds), auditory brainstem response, and transient click-evoked otoacoustic emissions were administered. The results were suggestive of a space-occupying lesion, and the patient was referred to a pediatric neurologist and neurosurgeon. A cerebellar pilocytic astrocytoma was found. The patient's audiologic profile is described, along with implications for pediatric neurologic evaluations.

Aggressive Cranial Vault Decompression for Cranial Hyperostosis: Technical Case Report of Two Cases

OBJECTIVE AND IMPORTANCE:

Camurati-Engelmann's disease, also known as progressive diaphysial dysplasia, is a disorder of the bone metabolism. Neurological manifestations of progressive diaphysial dysplasia include cranial nerve dysfunction, generalized weakness, cerebellar herniation, and increased intracranial pressure. In the past, surgical intervention has been of limited and temporary benefit. We present two patients with cranial hyperostosis secondary to Camurati-Engelmann's disease who were treated successfully with a single surgery involving a combination of multiple craniotomies for cranial vault decompression.

CLINICAL PRESENTATION:

Two patients presented with signs and symptoms of increased intracranial pressure secondary to Camurati-Engelmann's syndrome. Radiological workup revealed marked cranial hyperostosis.

INTERVENTION:

The patients underwent aggressive cranial vault decompression. Multiple craniotomies were performed, and the inner table was then drilled down until the bone was 1 cm thick.

CONCLUSION:

Effective surgical options are needed for clinically significant cranial hyperostosis. In an effort to further define operative management in these patients, we describe a single, aggressive surgical procedure that may be used for successful cranial decompression.

Pilomyxoid astrocytoma: diagnosis, prognosis, and management

Pilomyxoid astrocytoma (PMA) is a recently defined pediatric brain tumor; PMAs were previously classified within the pilocytic astrocytoma (PA) category. Nevertheless, PMA has different histological features and has been shown to behave more aggressively than PA. These findings indicate that PMA may be a unique entity that is distinct from PA, or it may be an unusual variant. To increase awareness of PMA within the neurosurgical community, the authors review the diagnostic criteria, prognostic implications, and current management of this recently described pediatric low-grade astrocytoma.

Pilomyxoid astrocytoma: diagnosis, prognosis, and management

Pilomyxoid astrocytoma (PMA) is a recently defined pediatric brain tumor; PMAs were previously classified within the pilocytic astrocytoma (PA) category. Nevertheless, PMA has different histological features and has been shown to behave more aggressively than PA. These findings indicate that PMA may be a unique entity that is distinct from PA, or it may be an unusual variant. To increase awareness of PMA within the neurosurgical community, the authors review the diagnostic criteria, prognostic implications, and current management of this recently described pediatric low-grade astrocytoma.

Expansion of arachnoid cysts in children

Arachnoid cysts are intracranial, space-occupying lesions that typically remain stable in size on serial imaging. The authors describe two cases of rapidly enlarging arachnoid cysts, including one located in the anterior fossa. In the first case a 7-month-old boy presented with increasing head circumference and a rapidly enlarging arachnoid cyst in the left middle fossa, which had been documented by serial imaging over the preceding 6 months. In the second case a 4-year-old girl presented with an arachnoid cyst compressing the right frontal lobe. The cyst had not been present on imaging studies performed during the perinatal period. In both cases, a craniotomy for open fenestration of the cyst was performed with successful resolution of the mass effect. Rare cases of expansion of arachnoid cysts have been reported in the literature. In this article the authors report the dramatic enlargement of two arachnoid cysts, including the first description of enlargement of an arachnoid cyst located in the anterior fossa.

Hypothalamic hamartoma in association with a suprasellar arachnoid cyst: a case report

A 5-year-old female presented with a history of precocious puberty and increased height. MRI of the brain revealed a nonenhancing hypothalamic mass and associated suprasellar arachnoid cyst. The patient underwent a right frontal craniotomy with orbital osteotomy for wide fenestration of the cyst. Intraoperatively, it was clear the mass represented a hamartoma with a very smooth glistening surface. For this reason, no biopsy of the wall was performed. Postoperatively, the patient remains neurologically intact and without any medication dependence. This case highlights the occurrence of a suprasellar arachnoid cyst in association with a hypothalamic hamartoma.

Surgical approaches to tumors of the lateral ventricle

Lateral ventricular tumors are rare lesions of the central nervous system, and because most tumors are benign or low grade, permanent cure can be achieved with complete removal. After adequate preoperative imaging discloses a lateral ventricular mass, the neurosurgeon has several options to choose from when determining the ideal surgical approach to the tumor. The surgical approach cannot be standardized, because the specific location, size, and vascularization of these deep-seated tumors are fundamental elements influencing the choice of surgical approach. Although access to the lateral ventricles may require additional preoperative considerations and planning, the combination of proper knowledge of the cortical and intraventricular anatomy with the familiarity and selection of an appropriate surgical approach will optimize the surgical outcome.

Sickle cell anemia with moyamoya disease: outcomes after EDAS procedure

Moyamoya disease is a relatively uncommon neurovascular complication of sickle cell anemia. We report a case series of six patients with sickle cell anemia who developed moyamoya disease and underwent encephaloduroarteriosynangiosis procedures. These six patients presented with either cerebrovascular accidents, transient ischemic attacks, or seizures, and subsequent magnetic resonance imaging scans were suggestive of moyamoya-like changes in the cerebral vasculature. Conventional cerebral angiography was used to confirm the diagnosis in all six patients. Four of six patients manifested a cerebrovascular accident before surgery, and two of these patients were compliant on a transfusion protocol at the time of their cerebrovascular accident. Bilateral (n = 4) or unilateral (n = 2) encephaloduroarteriosynangiosis procedures were performed without any complications. The patient who was stroke-free preoperatively had a cerebrovascular accident 2 weeks after the procedure; otherwise, all patients have remained free of neurovascular complications with an average follow-up of 33 months. Collateral anastomoses between external and internal carotid arteries were established by magnetic resonance angiography in three patients. The encephaloduroarteriosynangiosis procedure is a safe and effective treatment option in patients with sickle cell anemia who develop moyamoya disease.

Villous hypertrophy versus choroid plexus papilloma: a case report demonstrating a diagnostic role for the proliferation index

Diffuse bilateral enlargement of the choroid plexus has long been appreciated as a cause of shunt-resistant hydrocephalus in infants, most often secondary to cerebrospinal fluid overproduction. Despite the fact that such lesions have interchangeably been termed 'villous hypertrophy' (VH) or 'bilateral choroid plexus papilloma' (CPP), little attention has been paid to the pathological distinctions that characterize these two entities. We present a case of presumed VH in a 2-week-old female presenting with cerebrospinal fluid production-dependent hydrocephalus that ultimately required bilateral surgical ablation of the choroid plexus. Although the preoperative radiological diagnosis was consistent with VH, postoperative histological analysis suggested bilateral CPP. The neoplastic nature of the lesion was confirmed by specific staining for the proliferation index, showing an MIB-1 labeling index of 4%, characteristic of papilloma. Routine imaging and histological grading of choroid plexus hypertrophy and papilloma have not provided a reliable means of predicting malignant behavior or recurrence after surgical resection. Moreover, none of the previously reported cases of VH in the literature have analyzed pathological specimens for cellular proliferative potential. Therefore, we review the literature on VH and bilateral CPP and discuss the diagnostic and possible prognostic implications of distinguishing these variants by utilizing the MIB-1 marker for the proliferation index.

Improvement in brainstem auditory evoked potentials after suboccipital decompression in patients with chiari I malformations

OBJECT

The optimal treatment for patients with symptoms related to Chiari I malformation remains controversial. Although a suboccipital decompression with duraplasty is most commonly performed, there may be a subset of patients who improve in response to bone decompression alone. In an initial attempt to identify such patients, we performed a continuous study of intraoperative brainstem auditory evoked potentials (BAEPs) in patients undergoing a standard decompression with duraplasty and compared conduction times at three different time points: 1) baseline while the patient is supine (before positioning); 2) immediately after opening of the bone and release of the atlantooccipital membrane (that is, the dural band); and 3) after opening of the dura mater.

METHODS

Eleven children and young adults (mean age 9.8 years) with symptoms related to Chiari I malformation underwent suboccipital decompression and duraplasty with intraoperative monitoring of BAEPs and somatosensory evoked potentials (SSEPs). Six patients (55%) had associated syringomyelia. At baseline, the I to V interpeak latency (IPL) for both sides (total 21 BAEPs) was 4.19 +/- 0.22 msec (mean +/- standard deviation). After complete bone decompression and before the dura mater was opened, the I to V IPL decreased to 4.03 +/- 0.25 msec (p = 0.0005). When the dura was opened, however, no further decrease in the I to V IPL was detected (4.03 +/- 0.25 msec; p = 0.6). The SSEPs remained stable throughout the procedure.

CONCLUSIONS

In children and young adults undergoing suboccipital decompression with duraplasty for Chiari I malformation, the vast majority of improvement in conduction through the brainstem occurs after bone decompressionand division of the atlantooccipital membrane, rather than after opening of the dura. Additional studies are needed to establish whether the improvement seen with BAEP monitoring during bone decompression will predict long-term clinical improvement in these patients.

Chiari I malformation: potential role for intraoperative electrophysiologic monitoring

Intraoperative electrophysiologic monitoring can diminish the risk of neurologic injury by enabling the detection of injury at a time when it can be reversed or minimized. Although it is clear that in patients with cervical spine disease monitoring during surgery reduces the incidence of neurologic injury, almost no data are available regarding its utility in patients undergoing suboccipital decompression for Chiari I malformation. Patients with Chiari I malformation have caudal displacement of the cerebellar tonsils below the skull base, thereby creating a tight foramen magnum and cervical canal. Although the majority of pediatric neurosurgeons perform a bony decompression with duraplasty for symptomatic patients, there is much controversy regarding the amount of bony decompression required for clinical improvement and whether a duraplasty is essential. The authors therefore conducted a prospective, observational study using intraoperative brainstem auditory evoked potentials (BAEPs) and somatosensory evoked potentials in pediatric patients undergoing suboccipital decompressions for Chiari I malformations to determine whether there were consistent changes in intraoperative BAEPs that could help the operating surgeon decide how extensive a decompression was needed in these patients, and whether changes in BAEPs or somatosensory evoked potentials occurred during operative positioning that could be modified to reduce the risk of neurologic injury.

Attenuation of somatosensory evoked potentials during positioning in a patient undergoing suboccipital craniectomy for Chiari I malformation with syringomyelia

Intraoperative electrophysiologic monitoring can diminish the risk of neurologic injury by enabling the detection of injury at a time when it can be reversed or minimized. This report describes a 14-year-old girl with a Chiari's malformation type I and syringomyelia who underwent a suboccipital decompression and dural patch grafting with concurrent somatosensory evoked potentials. When the patient was turned into the prone position and the neck was flexed, the left-sided somatosensory evoked potential deteriorated. After the patient's neck was repositioned, the left median nerve potential improved but did not return to baseline. Postoperatively, the patient had decreased proprioception of her left arm, which completely resolved at 2-week follow-up. This single case report does not establish the need for routine somatosensory evoked potential monitoring. Nevertheless, deterioration of the potential in this case led directly to a change in the surgical positioning, which may have significantly reduced the chances of a permanent neurologic injury.

Extramedullary hematopoiesis within a frontoethmoidal encephalocele in a newborn with holoprosencephaly

We present the first report of extramedullary hematopoiesis (EMH) in an encephalocele. The patient was a new-born with semilobar holoprosencephaly, a frontoethmoidal encephalocele, and a large subdural hematoma. The encephalocele appeared as a hemorrhagic mass, protruding from the forehead to cover the right eye, without involvement of the sinuses or nasopharynx. Computerized tomography and magnetic resonance imaging studies ruled out other forms of holoprosencephaly and confirmed the continuity of the brain with the extruded mass. Immunohistochemistry confirmed the presence of an atrophic epithelium covering the mass. Histologic examination of the encephalocele revealed EMH both within and adjacent to malformed cerebral cortex, with a tendency for the hematopoietic cells to line up in columns within malformed cerebral cortex. We propose that a single event during the fourth week of gestation could both interrupt closure of the neural tube, giving rise to the encephalocele, and impair migration of the neural crest, leading to holoprosencephaly secondary to failure of neural crest derivatives to induce basomedial telencephalic differentiation. EMH may have been induced from hematopoietic stem cells in the richly vascular meningeal component of the encephalocele, in response to anemia and hypoxia.

Primary central nervous system lymphoma in childhood presenting as progressive panhypopituitarism

We report a 15-year-old boy who had isolated central diabetes insipidus initially diagnosed at age 11 years. A brain magnetic resonance imaging (MRI) was normal at the time. At age 12 years, growth hormone (GH) testing was performed because of a decline in linear growth rate and demonstrated GH deficiency. After a repeat normal brain MRI, GH therapy was begun. Three years later, hormonal testing revealed prepubertal gonadotropins and low testosterone levels, free thyroxine index, and morning cortisol levels. Repeat brain MRI demonstrated a 9-mm enhancing lesion in the region of the pituitary stalk. The pathologic diagnosis was that of a high-grade malignant B-cell lymphoma, suggestive of Burkitt Lymphoma. Growth hormone therapy has not been associated with an increased incidence of lymphoma. This report underscores the need for vigilance in follow-up brain imaging and hormonal evaluation in children with diabetes insipidus, especially those with evolving anterior hormone deficiencies.

Management of Chiari I malformations with holocord syringohydromyelia

The management of patients with Type I Chiari malformations (CM 1) with or without syringohydromyelia (SHM) has remained quite controversial, and many different surgical procedures have been advocated. Over the past several years, the authors have treated 7 children presenting with CM 1 and holocord syringohydromyelia with suboccipital decompression and duraplasty alone without intradural procedures. All children received MRI imaging at 2-4 months and 1 year postoperatively. On the early postoperative MRI examination, marked reduction in the syringohydromyelia was seen in 6 children, with minimal change in syrinx size in 1 child who was clinically improving after the operation. At 1 year, all children with early collapse remained collapsed, and the child with minimal early collapse demonstrated an approximately 50% reduction in syrinx size. Clinical follow-up (mean 30 months, range 21-50 months) showed good results in all patients: none of the children have required further neurosurgical intervention, and all have shown improvement in their preoperative function. One child with a 46 degrees scoliosis had a complete collapse of her SHM, but ultimately required spinal fusion. The presenting clinical findings, operative technique, MRI imaging and clinical outcomes will be discussed. The results from these 7 patients with CM 1 and holocord syringomyelia suggest that posterior fossa decompression alone (without intradural procedures) can provide excellent radiographic and clinical outcome.

Ventricular volume following third ventriculostomy

OBJECT

Ventricular size often shows no obvious change following third ventriculostomy, particularly in the early postoperative period, making postoperative evaluation difficult without expensive and often invasive testing in patients with equivocal clinical responses. The authors hypothesized that performing careful volumetric measurements would show decreases in size within the first 3 weeks after surgery.

METHODS

Volumetric measurements were calculated from standard 3 x 3-mm axial computerized tomography (CT) scans obtained immediately before and 3 and 21 days after surgery. Two independent investigators measured third ventricular volume in a series of 16 patients and lateral ventricular volume in 10 of the patients undergoing stereotactically guided endoscopic third ventriculostomy for noncommunicating hydrocephalus. Fifteen patients were symptomatically improved at the time the follow-up scan was obtained. Third ventricular volume decreased in all patients by a mean of 35% (range 7.8-95.1%) and lateral ventricular volume decreased in all patients by a mean of 33% (range 4.5-80.3%). The degree of change correlated with the length of preoperative symptoms (p < 0.005). The one patient who experienced no improvement showed no decrease in third ventricular volume. In seven of 10 patients, the decrease in third ventricular volume exceeded the decrease in lateral ventricular volume. Repeated measurements indicated that the 95% confidence interval for the authors' calculations varied around the mean by 2.5% for third ventricular volume and 1.2% for lateral ventricular volume. Long-term outcome was excellent, with only one case of delayed failure. The mean follow-up duration was 12 months.

CONCLUSIONS

Volumetric measurements calculated from standard CT scans will show a demonstrable decrease in ventricular volume soon after successful third ventriculostomy and can be helpful in assessing patients postoperatively. Although the third ventricle may exhibit a greater decrease, the lateral ventricular measurements are more accurate. Patients with more indolent symptoms show the smallest change.

Eosinophilic granuloma of the clivus: case report, follow-up of two previously reported cases, and review of the literature on cranial base eosinophilic granuloma

OBJECTIVE AND IMPORTANCE

To our knowledge, this is the first reported case of the use of stereotactic radiotherapy for an eosinophilic granuloma (EG) of the clivus. We report follow-up information on two previously reported cases and suggest a management plan for this rare lesion.

CLINICAL PRESENTATION

We report the case of a 4.5-year-old boy who presented with a complete abducens palsy on the right with an associated head turn. A computed tomographic scan of his head revealed a lytic lesion on that side, and magnetic resonance imaging showed the mass to be of low intensity on T1-weighted images and of high intensity on T2-weighted images with heterogeneous enhancement.

INTERVENTION

A transnasal stereotactic biopsy was performed, revealing an EG. The patient was treated with stereotactic radiotherapy, and he became symptom-free with radiographic resolution of his lesion. Reviewing the literature, we found 13 series with 87 cases of EG in the petrous portion of the temporal bone. EG in the cranial base occurring outside of the temporal bone or in the temporal bone and extending intracranially is, however, quite rare, with only nine other cases reported, two of them clival.

CONCLUSION

These findings suggest a classification schema in which cranial base EG lesions be grouped with either the more common extracranial petrous temporal bone lesions or the very rare intracranial lesions. Although there are few cases in the literature, treatment results indicate that clival EG, and perhaps all intracranial cranial base EGs, be treated by a biopsy alone, followed by surgery or stereotactic radiotherapy if there is an incomplete resolution of the symptoms or if there is a recurrence.

Massive intracranial arachnoid cyst in a developmentally normal infant: case report and literature review

Intracranial arachnoid cysts are developmental anomalies that are generally asymptomatic. We describe a 6-month-old boy with macrocephaly but normal neurological development who was found to have a rare, massive basal arachnoid cyst occupying most of the cranium and extending superiorly, causing significant shift due to mass effect. A cystoperitoneal shunt was placed, producing both a decrease in the arachnoid cyst dimensions and a concomitant reexpansion of parenchyma. After consideration of various management options, such a shunt system appears to offer a low risk of complications and a high likelihood of success.