Development of shunt valves used for treating hydrocephalus: comparison with endoscopy treatment

The pathophysiology of hydrocephalus is not clearly defined. Thus, treatment will remain empirical until a fuller understanding of the various forms of hydrocephalus is achieved. Valve-controlled shunting has been the mainstay of therapy since the late 1950s. Initially, shunting occurred from the ventricular system to the atrium. In the 1970s, VA shunts were replaced by ventriculoperitoneal shunts as the primary location for the distal end. Multiple types of one-way valve systems have been developed in the pursuit of draining the appropriate amount of CSF that avoids either overdrainage or underdrainage while preserving normal brain development and cognition. These valves are reviewed and compared as to their function. Other locations for the distal end of the shunting system are reviewed to include pleural space and gallbladder. The lumbar subarachnoid space as the proximal location for a shunt is also reviewed. The only other surgical alternative for treating hydrocephalus is endoscopic third ventriculostomy. Since 2000, approximately 50% of children with hydrocephalus have been shown to be candidates for ETV. The benefits are the lack of need for an artificial shunt system and thus lower rates of infection and over time fewer reoperations. Future progress is dependent on improved shunt valve systems that are affordable worldwide and ready availability of ETV in developing countries. Anatomic and molecular causes of hydrocephalus need to be defined so that medications or genetic modifications become available for potential cure of hydrocephalus.

Reduction of Total Knee Replacement Wear with Vitamin E Blended Highly Cross-Linked Ultra-High Molecular Weight Polyethylene

Ultra-high molecular weight polyethylene (UHMWPE) is a common bearing component in total knee replacement (TKR) implants, and its susceptibility to wear continues to be the long-term limiting factor in the life of these implants. This study hypothesized that in TKR systems, a highly cross-linked (HXL) UHMWPE blended with vitamin E will result in reduced wear as compared to a direct compression-moulded (DCM) UHMWPE. A wear simulation study was conducted using an asymmetric lateral pivoting ‘3D Knee’ design to compare the two inserts. The highly cross-linked UHMWPE was aged prior to the testing and force-controlled wear testing was carried out for 5 million cycles using a load-controlled ISO-14243 standard at a frequency of 1Hz on both groups. Gravimetric measurements of DCM UHMWPE (4.4±3.0mg/million cycles) and HXL UHMWPE with vitamin E (1.9±1.9mg/ million cycles) showed significant statistical differences (p<0.01) between the wear rates. Wear modes and surface roughness for both groups revealed no significant dissimilarities.

Modeling of peptide adsorption interactions with a poly(lactic acid) surface

The biocompatibility of implanted materials and devices is governed by the conformation, orientation, and composition of the layer of proteins that adsorb to the surface of the material immediately upon implantation, so an understanding of this adsorbed protein layer is essential to the rigorous and methodical design of implant materials. In this study, novel molecular dynamics techniques were employed in order to determine the change in free energy for the adsorption of a solvated nine-residue peptide (GGGG-K-GGGG) to a crystalline polylactide surface in an effort to elucidate the fundamental mechanisms that govern protein adsorption. This system, like many others, involves two distinct types of sampling problems: a spatial sampling problem, which arises due to entropic effects creating barriers in the free energy profile, and a conformational sampling problem, which occurs due to barriers in the potential energy landscape. In a two-step process that addresses each sampling problem in turn, the technique of biased replica exchange molecular dynamics was refined and applied in order to overcome these sampling problems and, using the information available at the atomic level of detail afforded by molecular simulation, both quantify and characterize the interactions between the peptide and a relevant biomaterial surface. The results from these simulations predict a fairly strong adsorption response with an adsorption free energy of -2.5 +/- 0.6 kcal/mol (mean +/- 95% confidence interval), with adsorption primarily due to hydrophobic interactions between the nonpolar groups of the peptide and the PLA surface. As part of a larger and ongoing effort involving both simulation and experimental investigations, this work contributes to the goal of transforming the engineering of biomaterials from one dominated by trial-and-error to one which is guided by an atomic-level understanding of the interactions that occur at the tissue-biomaterial interface.

Misidentification of vagus nerve stimulator for intravenous access and other major adverse events

The vagus nerve stimulator has become a standard modality for intractable pediatric epilepsy. We reviewed our experience with major adverse events, after accidental puncture of a stimulator wire by an emergency room physician seeking intravenous access to treat status epilepticus. The Children's National Medical Center database was reviewed for patients undergoing vagus nerve stimulator placement between January 1988 and June 2006. Patient characteristics, duration of therapy, and treatment-limiting adverse events were noted. Of 62 patients implanted over 8 years, 22 (35%) had adverse events which led to a change in therapy. Adverse events included prominent drooling, coughing, throat discomfort, dysphagia, wound infection, difficulty breathing, vomiting, vocal-cord weakness, lead failure, and iatrogenic (piercing of wire; surgical clipping of wire during revision). Eight patients required nonroutine surgical intervention (13%). There were two unusual case presentations. In a 13-year-old boy with status epilepticus at an outlying emergency department, the stimulator line was pierced in search of intravenous access. In a 25-year-old housepainter, neck paresthesias upon right lateral neck turning were attributed to insufficient strain relief. Treatment-limiting adverse events occurred in approximately one-third of patients. Unanticipated adverse events included misidentification of the wire for intravenous access, clipping of the wire during surgical dissection, and cervical dysesthesias associated with head-turning.

Association of human herpesvirus-6B with mesial temporal lobe epilepsy

BACKGROUND

Human herpesvirus-6 (HHV-6) is a beta-herpesvirus with 90% seroprevalence that infects and establishes latency in the central nervous system. Two HHV-6 variants are known: HHV-6A and HHV-6B. Active infection or reactivation of HHV-6 in the brain is associated with neurological disorders, including epilepsy, encephalitis, and multiple sclerosis. In a preliminary study, we found HHV-6B DNA in resected brain tissue from patients with mesial temporal lobe epilepsy (MTLE) and have localized viral antigen to glial fibrillary acidic protein (GFAP)-positive glia in the same brain sections. We sought, first, to determine the extent of HHV-6 infection in brain material resected from MTLE and non-MTLE patients; and second, to establish in vitro primary astrocyte cultures from freshly resected brain material and determine expression of glutamate transporters.

METHODS AND FINDINGS

HHV-6B infection in astrocytes and brain specimens was investigated in resected brain material from MTLE and non-MTLE patients using PCR and immunofluorescence. HHV-6B viral DNA was detected by TaqMan PCR in brain resections from 11 of 16 (69%) additional patients with MTLE and from zero of seven (0%) additional patients without MTLE. All brain regions that tested positive by HHV-6B variant-specific TaqMan PCR were positive for viral DNA by nested PCR. Primary astrocytes were isolated and cultured from seven epilepsy brain resections and astrocyte purity was defined by GFAP reactivity. HHV-6 gp116/54/64 antigen was detected in primary cultured GFAP-positive astrocytes from resected tissue that was HHV-6 DNA positive-the first demonstration of an ex vivo HHV-6-infected astrocyte culture isolated from HHV-6-positive brain material. Previous work has shown that MTLE is related to glutamate transporter dysfunction. We infected astrocyte cultures in vitro with HHV-6 and found a marked decrease in glutamate transporter EAAT-2 expression.

CONCLUSIONS

Overall, we have now detected HHV-6B in 15 of 24 patients with mesial temporal sclerosis/MTLE, in contrast to zero of 14 with other syndromes. Our results suggest a potential etiology and pathogenic mechanism for MTLE.

Management of pilocytic astrocytoma with diffuse leptomeningeal spread: two cases and review of the literature

INTRODUCTION

Leptomeningeal dissemination of juvenile pilocytic astrocytoma (JPA) is a rare event. We report two children with disseminated JPAs treated with a chemotherapeutic agent, temozolomide, after progression of the disease despite surgery, traditional chemotherapy, and/or radiation therapy.

CASE REPORTS

Patient 1 presented with hydrocephalus and progressive lower extremity weakness, and was found to have a suprasellar mass as well as extensive spinal disease. Ventriculoperitoneal shunting, decompressive laminectomy with spinal tumor debulking, and chemotherapy with carboplatin and vincristine were initially employed. However, disease progressed and craniospinal irradiation and temozolomide were used. Patient 1 remains in a fair condition today, 2 years later. Patient 2 presented at 8 months of age with failure to thrive. Imaging revealed a cystic lesion in the hypothalamic region with extensive subarachnoid metastatic disease to the spine. Biopsy was performed followed by chemotherapy with vincristine, cyclohexylchloroethylnitrosourea (CCNU), 6-TG, and procarbazine. Due to the continued progression of the disease, cytoreductive surgery was performed and her chemotherapeutic regimen was switched to temozolomide. Two years after initial presentation patient 2 is clinically much improved with stable residual disease.

DISCUSSION

We review the literature and discuss treatment strategies for this challenging disease.

Hypothalamic ganglioglioma treated by temporal lobectomy. Case report and review of the literature

The authors report the case of a hypothalamic ganglioglioma with left-sided temporal lobe extension in an 8-year-old girl who presented with seizures. Other cases of ganglioglioma involving the hypothalamus have been reported in the literature; however, this site of origin is exceedingly rare and worthy of report. Treatment involved medial temporal lobectomy with the hypothalamic component of the tumor remaining untouched. The patient recovered postoperatively with no neurological deficits and was seizure free at 12 months. Neither radio- nor chemotherapy was recommended because of the tumor histology, location, and the patient's age. The authors recommend follow up and surgical treatment for possible tumor recurrence. The prognosis for hypothalamic ganglioglioma is unknown.

Bacterial Adhesion to Surfactant-modified Silicone Surfaces

OBJECTIVE

Ventricular shunt infections are a major contributor to morbidity in patients being treated for hydrocephalus. The majority of these infections are from Staphylococcus epidermidis. Prevention of bacterial adhesion to the silicone surface of a ventricular catheter could decrease shunt infections. We studied the effectiveness of a surfactant and/or 2% iodine prewash on preventing bacterial adhesion to Silastic catheter material.

METHODS

In a laboratory setting, various concentrations of a surfactant, Poloxamer-188 (P188), and a bactericidal agent, iodine, were compared against a control solution in their ability to prevent bacterial adhesion of S. epidermidis to a silicone surface. Silicone wafers were soaked for 1 hour in the test solution, then inoculated and incubated with S. epidermidis for 24 hours. Bacterial counts were then obtained and compared.

RESULTS

The most effective method tested in this study was 20% P188, which allowed only 3.02% bacterial adhesion compared with 22.2% bacterial adhesion in the control (P < 0.001). P188 at a 10% concentration or 20% mixed with iodine had the next most effective inhibition. Of the germicidal solutions, a 5-ppm solution of iodine was the most effective. The most ineffective method tested was 2 ppm iodine, which allowed 13.2% bacterial adhesion.

CONCLUSION

Use of a surfactant and/or a germicidal will provide some protection against bacteria attaching to silicone surfaces before they are surgically implanted. The use of a surfactant soak of 20% P188 or iodine at a concentration of 5 ppm before inoculation with S. epidermidis significantly decreased the bacterial adhesion to silicone wafers. This finding has relevance to clinical practice because it highlights a simple step undertaken before implanting a ventricular catheter that could reduce the adhesion rate of the most common contaminant of these catheters. This step may become an important factor in decreasing infection rates in shunt-dependent patients.

Prognostic factors in children and adolescents with low-grade oligodendrogliomas

Few reports exist describing the progression-free and overall survival of children with low-grade (WHO grade II) oligodendrogliomas treated uniformly with aggressive surgery but without adjuvant chemotherapy or radiation therapy. Furthermore, significant prognostic features, including the MIB-1 labeling index (LI), have not been reported for children with oligodendrogliomas. The medical records of 20 consecutive patients with low-grade oligodendrogliomas were reviewed. All patients had been treated with aggressive surgical resection. Adjuvant chemotherapy and radiation therapy were reserved for radiographic or clinical progression. These patients have been followed for a median of 5.5 years (range 0.5-11.5 years) after diagnosis. To date, there have been no patient deaths. Six of the 20 patients experienced tumor progression at a median of 2.2 years (range 0.4-4.8 years) following the initial surgery. The MIB-1 LI was infrequently greater than 5. Of several prognostic factors for subsequent tumor progression that were examined, only tumors located within the parietal lobes were associated with a worse progression-free survival. Other risk factors, including presenting symptoms, age at diagnosis, MIB-1 LI and the extent of tumor resection, were not associated with an increased frequency of tumor progression.

New methods for the evaluation and treatment of craniofacial dysostosis-associated cerebellar tonsillar herniation

Herniation of the cerebellar tonsils may occur in children with craniofacial dysostosis (e.g., Apert, Carpenter, Crouzon, Jackson-Weiss, Pfeiffer, and Saethre-Chotzen syndromes), occasionally, with serious sequelae. Cerebellar tonsillar herniation is probably acquired in children affected with craniofacial dysostosis, raising the question, How should we be screening for this anomaly? This retrospective clinical study was undertaken to review the authors' series of what they believe to be a new surgical treatment for craniofacial dysostosis-associated cerebellar tonsillar herniation and to report their experience with a new screening technique. In an attempt to find a low-cost alternative to the use of routine magnetic resonance imaging for identifying cerebellar tonsillar herniation, the authors instituted sagittal reformatting of three-dimensional computed tomographic scans through the foramen magnum. Scans are considered positive if soft tissue is noted to extend below the foramen magnum, and all positive scans are further evaluated by magnetic resonance imaging with flow studies of the cerebrospinal fluid. These sagittally reformatted scans add no additional cost, and they seem to be highly sensitive in screening for cerebellar tonsillar herniation. Over a 13-month period, five children (one with Apert syndrome; four with Crouzon syndrome) with craniofacial dysostosis-associated cerebellar tonsillar herniation underwent isolated anterior cranial vault remodeling to treat observed brachycephaly (standard neurosurgical posterior decompression was not performed). All patients (mean age, 6 years; range, 2 to 14 years) were without the symptoms typically associated with cerebellar tonsillar herniation. Only those patients who had preoperative and postoperative magnetic resonance imaging scans were included in this review. All patients showed some improvement by the authors' magnetic imaging criteria after anterior cranial vault remodeling. Despite these findings, the authors recommend that until the anterior approach can be further studied, symptomatic children should undergo standard posterior neurosurgical decompression. The authors speculate that the presence of cerebellar tonsillar herniation may be a relative indication for decompressing the cranial vault in the craniofacial dysostoses. In addition, they propose that the descriptive anatomic term "cerebellar tonsillar herniation" be substituted for the misnomer "Chiari malformation" in these children.

The slit ventricle syndrome

This article reviews the collection of entities that still are described as slit ventricle syndrome, discusses the various diagnoses, and reviews the investigation and treatment of children with small ventricles after ventricular shunting.

Deep venous thrombosis with suspected pulmonary embolism: detection with combined CT venography and pulmonary angiography

PURPOSE

To determine the frequency and location of deep venous thrombosis at computed tomographic (CT) venography after CT pulmonary angiography in a large series of patients clinically suspected of having pulmonary embolism and to compare the accuracy of CT venography with lower-extremity venous sonography.

MATERIALS AND METHODS

Venous phase images were acquired from the diaphragm to the upper calves after completion of CT pulmonary angiography in 650 patients (373 women, 277 men; age range, 18-99 years; mean age, 63 years) to determine the presence and location of deep venous thrombosis. Results of CT venography were compared with those of bilateral lower-extremity venous sonography in 308 patients.

RESULTS

A total of 116 patients had pulmonary embolism and/or deep venous thrombosis, including 27 patients with pulmonary embolism alone, 31 patients with deep venous thrombosis alone, and 58 patients with both. Among 89 patients with deep venous thrombosis, thrombosis was bilateral in 26, involved the abdominal or pelvic veins in 11, and was isolated to the abdominal or pelvic veins in four. In patients in whom sonographic correlation was available, CT venography had a sensitivity of 97% and a specificity of 100% for femoropopliteal deep venous thrombosis.

CONCLUSION

Combined CT venography and pulmonary angiography can accurately depict the femoropopliteal deep veins, permitting concurrent testing for venous thrombosis and pulmonary embolism. CT venography also defines pelvic or abdominal thrombus, which was seen in 17% of patients with deep venous thrombosis.

Imaging after head trauma: why, when and which

CT scanning is the current first imaging technique to be used after head injury, in those settings where a CT scan is available. The first scan is usually done without contrast enhancement. The value of CT is the demonstration of scalp, bone, extra-axial hematomas and parenchymal injury. It is rapid and easily done in the presence of the multiple monitors that many trauma patients have in place. It can be used to demonstrate the bony anatomy of the spine and is good for evaluation of abdominal and chest trauma also. MRI is more sensitive for all posttraumatic lesions other than skull fracture and subarachnoid hemorrhage, and can demonstrate parenchymal spinal cord injury. The cons are a longer scanning time, interference of the imaging by certain ICP monitors and problems with the positions of the monitoring equipment and ventilators outside the MRI magnetic field. MRI will be used increasingly to study early head injury because of its ability to measure cerebral blood flow, cerebral blood volume and the location and extent of cerebral edema. If the CT does not demonstrate pathology adequate to account for the clinical state, MRI is warranted. Follow up is best done with MRI as it is more sensitive to parenchymal change than is CT.

Surgical technique for the insertion of grids and strips for invasive monitoring in children with intractable epilepsy

Despite improved imaging, and electrical and magnetic external mapping, there are a large number of children with intractable epilepsy in whom a focus cannot be defined by non-invasive techniques. Invasive monitoring with depth electrodes, electrode grids and/or strips is required in up to 50% of children with a suspected focal seizure disorder. In children with suspected temporal lobe epilepsy the invasive techniques are required to identify which temporal lobe is the primary focus, to separate temporal from frontal foci, and to define the extent of involvement of the lateral temporal cortex. In children and infants with non-temporal epilepsy, invasive monitoring is required to define the epileptogenic zone and to map areas of cortical specialization. The current techniques used for surgical implantation are described here. In a correctly selected population invasive monitoring will define the epileptogenic focus or foci in 90% of children; 80% will have surgically treatable epilepsy. Infection rates are less than 1% for subdural strips and 6% for grids. In 88 cases no incidence of meningitis occurred.

Surgical treatment of focal epilepsy in children: results in 37 patients

This report concerns 37 children and teenagers operated upon for intractable seizures between 1990 and 1994. Follow-up is at least 3 years. Fourteen children underwent pure temporal lobe resections; 71% are seizure free, and 93% have a better than 90% decrease in seizure frequency. The presence of a lesion on magnetic resonance imaging, the side of the lesion, or the presence of abnormal pathology had no influence on the result of resection. 28% of the children who had extratemporal resections are seizure free, and 83% have a greater than 90% decrease in seizure frequency. There was a trend to better results in those with a lesion on magnetic resonance imaging. In the small group with temporal plus extratemporal foci, the results were poor with only 60% showing a greater than 90% reduction in seizure frequency.

Consensus: craniofacial synostoses. Apert and Crouzon syndromes

A critical analysis of functional and morphological aspects of Apert and Crouzon syndromes is presented, with reference to the papers presented in this session of the Consensus Conference on Craniosynostoses. Targets and limits of surgical correction are also discussed.

Ventriculoperitoneal shunts for hydrocephalus: a focus group discussion on the selection of shunt systems in pediatrics. A report of the Pediatric Neurosurgery Research Group meeting, December 1992

As part of the Continuing Quality Improvement Study, phase I, 12 pediatric neurosurgeons participated in a discussion group to respond to the various issues related to selection of ventriculoperitoneal shunt systems in their practice. It was estimated that between then all the 12 participants performed approximately 1200 shunt procedures per year in the USA. The data were analyzed by grid and fish-bone charts as part of the data collection. All 12 participants indicated that they preferred a reservoir in the shunt system, 8 of them indicating that they preferred this for a manual test of the system. Three indicated that they did not routinely manipulate the system for testing. One participant stated that he placed a reservoir within the shunt system primarily to prevent migration of the ventricular catheter. Nine neurosurgeons indicated that they employed cranial valves in their shunt systems, and three indicated that they employed slit-end peritoneal catheters only. In reference to Delta valves, nine participants indicated that they employed them on occasions. In reference to pressure in the valve system, one participant employed high-pressure valves at all times, five employed only medium-pressure systems, and the remaining six always employed low-pressure valves. All 12 neurosurgeons stated that the incidence of symptomatic slit ventricle in their practices was between 1% and 5%, in their mind irrespective of the system used. It was concluded that any form of ventriculoperitoneal shunt, with or without valves, with slit-end valves or cranial valves seemed to work equally well in the hands of a dedicated pediatric neurological surgeon.(ABSTRACT TRUNCATED AT 250 WORDS)

Transfacial approaches to the cranial base

This article classifies and describes the anterior transfacial approaches to the cranial base as determined by the anatomic location of the lesions. With the use of craniofacial techniques, many of these lesions now may be resected without any significant functional or anesthetic morbidity.

Observations on the use of rigid fixation for craniofacial deformities in infants and young children

With the introduction of smaller plating systems, many surgeons have adopted their use for craniofacial procedures in infants and small children. We have encountered some previously undescribed problems associated with the use of plates and screws in infants and children. These problems can be classified into three general areas: 1) Plate displacement. This occurs after placement of the metal plates on the outside of the infant calvaria. With subsequent growth, these plates and screws may be found along the inner cortex of the skull with screw points embedded through dura. 2) Plate and screw isolation. In certain locations in young children, plates placed on the outer cortex of bone may later be found to be more prominent, isolated on a peninsula of bone. 3) Plate placement. We have also encountered plates that have been placed along the inner cortex of the skull during a previous operative procedure. This makes subsequent surgery extremely difficult and may increase the risk for secondary surgery. We propose that a previously described model for growth, involving areas of bony resorption and deposition, may be responsible for the observed plate displacement.

Dissociation between delayed alternation and memory after pediatric head injury: relationship to MRI findings

This study investigated the usefulness of a delayed alternation task in characterizing the cognitive sequelae of closed head injury in children and adolescents. Verbal learning and memory (California Verbal Learning Test) were also studied for comparison. Sixty-two closed head injury patients (mean age, 9.6 years), who were studied after an average postinjury interval of 20 months, were divided according to both their lowest postresuscitation Glasgow Coma Scale score (3 to 8 versus 9 to 15) and age range (5 to 7 years versus 8 to 16 years) at the time of testing. Magnetic resonance imaging was performed to evaluate the relationship of focal brain lesions to cognitive and memory performance. Fifty-six neurologically normal children (mean age, 9.9 years) were tested on the same measures. The results disclosed no relationship between delayed alternation performance and severity of injury. In contrast, verbal memory was impaired in the severely-injured patients, relative to both controls and less severely-injured patients. Frontal lobe (but not extrafrontal) lesion size incremented the Glasgow Coma Scale score in predicting verbal memory, but there was no relationship between focal brain lesions and delayed alternation performance. In contrast to the tendency for more efficient delayed alternation performance in the 5- to 7-year-old subjects than in the 8- to 16-year-old subjects, verbal memory significantly improved with age in the closed head injury and control groups. Notwithstanding our essentially negative findings for delayed alternation, it is possible that this task may be useful for assessing frontal lobe injury in younger children or infants.(ABSTRACT TRUNCATED AT 250 WORDS)

Brain tumors in children under 2 years: treatment, survival and long-term prognosis

Survival for children with brain tumors less than 2 years of age at diagnosis is dismal, and the quality of life of long-term survivors poor. Between 1975 and 1987, 78 (13%) of 579 patients with brain tumors treated at Children's Hospital of Philadelphia were under 2 years of age. Tumor site was posterior fossa in 31 (40%) and supratentorial in 47 (60%). Nine of 37 patients (24%) with malignant tumors, and 30 of 41 (73%) patients with benign tumors are alive with a mean follow-up of 116 months. Long-term survival after treatment with chemotherapy alone occurred in 10 patients, including 3 with malignant tumors. In 5 additional patients, chemotherapy delayed the need for irradiation a mean of 30 months. Of the 29 patients who relapsed after initial therapy, 12 are alive without progressive disease (2 patients with malignant tumors and 10 with benign tumors) a mean of 80 months after relapse, 2 children are alive with progressive disease, and 14 died a median of 48 months (range 9-115 months) after relapse. Twenty-one of the 39 survivors have minimal or no neurological or intellectual dysfunction. Surviving patients treated with surgery and chemotherapy have better intellectual function than patients treated with surgery and radiation (with or without chemotherapy) in that 8 of 10 children treated with surgery and chemotherapy have normal or above normal intelligence compared with 5 of 12 children receiving irradiation before their second birthday.

Craniofacial neurosurgical approach for extensive hyperostotic meningioma

We present a patient with a craniofacial meningioma that had been considered inoperable for 8 years but has now been successfully treated using the combined neurosurgical and craniomaxillofacial approach. The tumor extensively involved the meninges, skull, face, left orbit, and maxilla. Vision and mild proptosis of the left eye had worsened over the last several years. Computed tomography and magnetic resonance imaging scans revealed an extensive intraosseous meningioma with intracranial and extracranial extension. An angiogram revealed an intensely vascularized mass supplied by a markedly enlarged ophthalmic artery. The tumor was approached through a bicoronal incision. The meningioma that extended into the dura was removed entirely from the brain. The left orbital roof and the lateral and medial walls were resected along with the meningioma, which extended through the orbit into the maxilla. The defect in the dura was closed with a pericranial flap. Split parietal bone and lyophilized cartilage were used for reconstruction of the cranial and orbital defects. Three and a half months after the initial surgery, further reconstruction was performed using calvarial, rib, and iliac bone and lyophilized cartilage. A methylmethacrylate implant was inserted but then removed due to chronic wound drainage. It was substituted with demineralized perforated bone implants from Pacific Coast Tissue Bank. Seventeen months after the initial surgery, there was no evidence of the tumor.

Massive teratomas involving the cranial base: treatment and outcome--a two-center report

Massive teratomas involving the cranial base are extremely rare, and to our knowledge, there are no reports of this condition in surviving children. We describe the management of four cases of massive intracranial teratomas, reflecting a combined experience from two major referral centers. We found that when corrected at an early age, the brain parenchyma demonstrated a remarkable ability to reexpand in those children who had appeared to have sustained parenchymal deficits secondary to the mass effect from the tumor. Follow-up thus far suggests that regional skull growth potential may be compromised in some of these patients. Often, the exact pathologic diagnosis of these entities is somewhat different, since they may fall somewhere within the hamartoma-heterotopia-teratoma continuum. We believe that the best care of these children is offered through a combined simultaneous craniofacial and neurosurgical approach.

Fusiform dilatations of the carotid artery following radical surgery of childhood craniopharyngiomas

Between 1982 and 1990, a series of 31 children with craniopharyngiomas underwent initial surgery at the Children's Hospital of Philadelphia with an attempt at total tumor removal. Nine (29%) of them were found to have fusiform dilatation of the supraclinoid carotid artery either at the time of surgery for recurrence (one patient) or on routine surveillance with enhanced computerized tomography 6 to 18 months postoperatively (eight patients). The finding of carotid enlargement was confirmed in seven cases with magnetic resonance angiography and in one case with a formal arteriogram. Eight of the nine patients remain alive at a mean of 3.7 years after diagnosis. None have experienced hemorrhage or other symptoms referrable to fusiform dilatation of the carotid artery, which is believed to result from surgical manipulation of the carotid artery.

Complications of third ventricle surgery

The anatomy and physiology of the structures in the region of the third ventricle are reviewed as they pertain to the various surgical approaches to this area. The peri-third ventricular area of the brain, an area less than 1% of the whole brain, is the center for a host of homeostatic mechanisms; temperature, osmolality, pituitary endocrine function, sympathetic and parasympathetic control, appetite and for a variety of behavioral drives, e.g. sex. In addition, memory circuits pass through this area, although current models exclude the immediate hypothalamus as playing a major role in memory. The various surgical approaches are reviewed and unavoidable injury as a result of the lesion or complications related to the surgery are considered in three categories: those that result from the surgical exposure itself; those that result due to maintaining the surgical exposure, e.g. retractor damage; and those that are unavoidable as a result of the infiltrative nature of the lesion itself. The causes of injury are further categorized into those due to arterial, venous, or direct cerebral tissue injury. Ways to minimize complications are presented.

Suprasellar germinomas in childhood. A reappraisal

Germinomas in childhood may arise in both the suprasellar and pineal region, and outcome has been reported to be worse for suprasellar germinomas with a 5-year survival rate of 20% as compared to 60% for pineal germinoma. To determine the factors impacting on outcome, the results of a uniform treatment approach were evaluated and included primary surgical debulking (PSD) and systemic craniospinal axis radiation (CSRT) for suprasellar germinomas. Between 1976 and 1985 ten consecutive patients (seven females, three males) with the pathologically confirmed diagnosis of suprasellar germinoma were treated. Outcome was compared to four male patients with pineal germinoma treated over the same time period and series of patients reported in the literature. At diagnosis the mean age of patients with suprasellar germinoma was 13.9 years (range, 8.9 to 9.4 years). Symptoms were present for a mean of 18 months (range, 2 to 72 months) prior to diagnosis and included diabetes insipidus, anterior pituitary dysfunction, decreased vision, headache, vomiting, and diplopia. Staging studies, including myelography (n = 4) and cerebrospinal fluid cytology (n = 7), disclosed dissemination in only one child. Surgical treatment included biopsy in three cases, partial resection in five, and total resection in two; no permanent postsurgical complications were noted. The mean radiation therapy dose to the tumor site was 4953 cGy (range, 4400 to 5250 cGy) and to the spine 3354 cGy (range, 3000 to 4000 cGy). Patients were followed for a mean period of 5.1 years (range, 1.9 to 10.5 years). One patient with SG who did not receive treatment initially developed a pineal tumor after diagnosis; she was treated with PSD and CSRT and is asymptomatic 5 years later. All the remaining patients are alive and remain disease-free. Surgical resection and CSRT results in excellent disease control for children with suprasellar germinomas, and outcome is similar to those patients with pineal germinoma.

Leptomeningeal spread of intramedullary spinal cord tumors. Report of three cases

Three patients with intramedullary spinal cord tumors and secondary leptomeningeal spread of their tumors are presented. Two patients had astrocytomas and one had a ganglioglioma. Two tumors were located in the cervical spinal cord and one within the thoracic spinal cord. Review of the past and recent literature shows leptomeningeal dissemination of spinal cord tumors to be relatively rare, but it should be suspected and investigated in any patient whose condition deteriorates following removal of a spinal cord neoplasm.

Results of the treatment of children with recurrent gliomas with lomustine and vincristine

Gliomas comprise over 50% of all childhood brain tumors. Treatment of recurrent childhood gliomas has been disappointing and the effectiveness of therapy has been difficult to judge because of the variable natural history of the disease. Information gathered recently has suggested that treatment with [1-(2-chloroethyl)-3-cyclohexyl-1-nitrosourea)] (CCNU) and vincristine (VCR) after radiotherapy is effective in prolonging survival in children with newly diagnosed anaplastic gliomas. The authors have used these same drugs--CCNU (100 mg/m2) and VCR (1.5 mg/m2 up to a maximum dose of 2 mg)--in 6-week cycles for a maximum of eight cycles in children with recurrent gliomas. To date, 15 patients have been treated; five patients had malignant gliomas and ten low-grade gliomas. Three children showed improvement, five had stable disease, and seven had progressive disease. Of the five patients with malignant gliomas, four progressed within two cycles of treatment and one had stable disease for 7 months on treatment and then relapsed. Seven of ten children with low-grade gliomas benefitted from treatment and six remain in continuous remission a median of 16 months after initiation of therapy. Three of these children are off all therapy 21, 30, and 30 months after treatment, respectively. Therapy was well tolerated and toxicity consisted primarily of reversible bone marrow suppression. The authors conclude that CCNU and VCR chemotherapy is effective in children with recurrent low-grade gliomas and can result in relatively long-term disease stabilization. In limited experience of the authors, it is not of benefit in children with recurrent anaplastic lesions.

Treatment of chiasmatic/hypothalamic gliomas of childhood with chemotherapy: an update

Chiasmatic/hypothalamic gliomas (CHG) of childhood may cause progressive neurological and visual deterioration. Radiotherapy results in at least transient stabilization of tumor growth in most patients but may also have adverse long-term effects, especially in young children. Since 1977, children with progressive CHG under 5 years of age at diagnosis have been treated with combination chemotherapy (actinomycin D and vincristine) without radiotherapy. Twenty-four patients, a median of 1.6 years of age at diagnosis, have been treated and followed for a median of 4.3 years (range, 0.3-10 years). All patients are alive. Nine have developed radiographic or clinical progression, occurring a median of 3 years (range, 2-6.5 years) after initiation of treatment. Fifteen of 24 (62.5%) have remained free of progressive disease and have received no other therapy. Tumor shrinkage was documented in 9 of 24 patients but did not clearly relate to long-term outcome. Full-scale intelligence quotient (IQ) obtained a median of 3.5 years after diagnosis in patients who received only chemotherapy was a mean of 103 (range 84-133). We conclude that chemotherapy can significantly delay the need for radiotherapy in children with CHG and such a delay may be beneficial regarding long-term outcome.

Results of a pilot study of hyperfractionated radiation therapy for children with brain stem gliomas

The majority of children with brain stem gliomas develop progressive disease within 18 months of diagnosis and treatment. Radiotherapy (RT) is of transient benefit in most patients and higher total doses of RT have been related to improved survival. The amount of RT which can be given is limited by the tolerance of the surrounding brain. Hyperfractionated RT theoretically allows higher doses of RT to be tolerated by the brain. Sixteen children with brain stem gliomas were treated on a hyperfractionated RT schedule, receiving 120 cGy of RT twice daily, to a total dose of 6480 cGy. All patients tolerated treatment well. Eleven of 15 (73%) evaluable patients had a response to treatment and two (13%) others had stable disease. One patient developed progressive disease during treatment. All patients were tapered off steroids by the completion of treatment. Thirteen of 16 (81%) patients developed progressive disease at a median of 7 months after diagnosis and three remain in remission 8, 12, and 15 months following diagnosis. These results were similar to those of historical controls. Two patients were surgically explored at time of relapse and 5 have had an autopsy. No acute or subacute neurologic toxicity was seen; but long-term detrimental effects on brain could not be assessed. The implications of this study are that escalations of the dose of hyperfractionated RT can be entertained for children with brain stem gliomas.

Radioimmunodetection of human glioma xenografts by monoclonal antibody to epidermal growth factor receptor

Murine IgG2a monoclonal antibody (MAb) 425 specifically detects epidermal growth factor receptor, which is expressed on human gliomas and tumors of other tissue origin but rarely on normal brain tissues, and not at all on bone marrow and peripheral blood cells. 131I-labeled F(ab')2 fragments of this MAb injected into nude mice grafted with U-87 MG glioma cells preferentially localized in tumor tissue compared to normal mouse tissues, as determined by differential tissue counting of radioactivity. The mean tumor-to-tissue ratios of radioactivity ranged between 8.2 (blood) and 55.8 (muscle) at 2 days after the injection of 15 muCi of 131I-425 F(ab')2/mouse. Radiolabeled fragments of an anti-hepatitis virus IgG2a MAb did not localize in tumors. The localization index derived from the ratios of specific antibody to indifferent antibody in tumor tissue relative to blood was 9.94 at 2 days following the MAb injection. The labeled MAb did not localize in a xenograft of colorectal cancer tumor, which does not express the epidermal growth factor receptor. Tumors could be located by whole-body gamma-scintigraphy without background subtraction following the injection of 100 muCi of radiolabeled MAb 425 F(ab')2 fragments. The data suggest that MAb 425 is a likely candidate for clinical diagnostic and radioimmunotherapy trials.

Symptomatic Arnold-Chiari malformation: review of experience with 22 cases

Twenty-two patients with closed myelomeningoceles, shunted hydrocephalus, and symptomatic Arnold-Chiari malformations were studied retrospectively. Seventeen of the 22 patients were aged 6 months or younger; five patients were aged 3 to 23 years. Patients in the younger group presented with stridor, apnea, and/or feeding difficulty; those in the older group presented with hemiparesis, quadriparesis, oscillopsia, nystagmus, or opisthotonos. Fourteen of the 17 younger patients underwent surgical decompression of the Arnold-Chiari malformation: 10 within 18 days following the onset of symptoms and four on Day 19 or later. Of the 10 infants with early treatment, five eventually died secondary to continued symptoms and five survived. Of those surviving, three were asymptomatic and two had continuing symptoms but were improved over their preoperative state. Among the four patients undergoing surgery later, two died, one had lessening of stridor, and one had complete relief of symptoms. Of the three infants not undergoing decompression, two died and one eventually became asymptomatic. All five of the older patients underwent decompression and all had complete resolution of their preoperative symptoms and signs. The authors conclude that while decompression of a symptomatic Arnold-Chiari malformation may be effective in children and adults, this treatment does not always improve the clinical condition of infants. This may be the result of ischemic/hypoxic effects on the infant's brain stem, which may not be organized normally at birth.

Pineocytomas of childhood. A reappraisal of natural history and response to therapy

Pineocytomas are pineal parenchymal tumors composed of differentiated cells histologically similar to those of the mature pineal gland. Little is known about the incidence, pattern of growth, or response to treatment of pineocytomas. Between 1975 and 1985, six children with pineocytomas were treated at our institution, and pineocytomas constituted 11% of all newly diagnosed pineal region tumors. The clinical, radiographic, and pathologic features of these six patients with pineocytomas are presented. Initial treatment for these children included craniospinal plus supplemental local radiotherapy (three), local radiotherapy alone (one), or radiation therapy plus adjuvant chemotherapy (two). Four of six patients had tumor recurrence a median of two years after diagnosis. Three patients had leptomeningeal dissemination, one at the time of diagnosis and two following therapy. Our findings suggest that: biopsy is necessary to distinguish pineocytomas from other pineal region tumors; radiation therapy alone is inadequate; and these tumors are aggressive in the pediatric population, with a high propensity for leptomeningeal dissemination.

The shaken baby syndrome. A clinical, pathological, and biomechanical study

Because a history of shaking is often lacking in the so-called "shaken baby syndrome," diagnosis is usually based on a constellation of clinical and radiographic findings. Forty-eight cases of infants and young children with this diagnosis seen between 1978 and 1985 at the Children's Hospital of Philadelphia were reviewed. All patients had a presenting history thought to be suspicious for child abuse, and either retinal hemorrhages with subdural or subarachnoid hemorrhages or a computerized tomography scan showing subdural or subarachnoid hemorrhages with interhemispheric blood. The physical examination and presence of associated trauma were analyzed; autopsy findings for the 13 fatalities were reviewed. All fatal cases had signs of blunt impact to the head, although in more than half of them these findings were noted only at autopsy. All deaths were associated with uncontrollably increased intracranial pressure. Models of 1-month-old infants with various neck and skull parameters were instrumented with accelerometers and shaken and impacted against padded or unpadded surfaces. Angular accelerations for shakes were smaller than those for impacts by a factor of 50. All shakes fell below injury thresholds established for subhuman primates scaled for the same brain mass, while impacts spanned concussion, subdural hematoma, and diffuse axonal injury ranges. It was concluded that severe head injuries commonly diagnosed as shaking injuries require impact to occur and that shaking alone in an otherwise normal baby is unlikely to cause the shaken baby syndrome.