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Object. Craniopharyngiomas originate from the same cells as squamous cell skin carcinoma, which can be treated successfully with interferon-α (IFNα)-2a. The authors evaluated the activity and toxicity of systemic IFN in young patients with craniopharyngiomas.Methods. Fifteen patients between the ages of 4.2 and 19.8 years who had progressive or recurrent craniopharyngiomas were enrolled in this study. Nine of these patients had never received external-beam radiation therapy. Therapy consisted of 8,000,000 U/m2 IFNα-2a administered daily for 16 weeks (induction phase) followed by the same dose three times per week for an additional 32 weeks (maintenance phase). Of the 12 patients who could be evaluated, radiological studies demonstrated a response to treatment in three with predominantly cystic tumors (one minor response, one partial response, and one complete response); one of these patients also showed improvement in visual fields. The size of the cystic component of the tumors often increased temporarily during the first several months of therapy. Three patients met the criteria for progressive disease during therapy. The median time to progression was 25 months. The need for radiation therapy in patients treated with IFN was delayed for 18 to 35 months (median 25 months) in six patients. All patients developed transient flulike symptoms shortly after receiving the first dose of IFN. Other toxicities (predominantly hepatic, neurological, and cutaneous) were seen in nine (60%) of the 15 patients during the first 8 weeks of treatment but resolved after temporary discontinuation and/or dose reduction.Conclusions. Interferon-α-2a is active against some childhood craniopharyngiomas; its toxicity precludes administration of high daily doses, and the optimum dose level and schedule remain to be defined.

✓ A porcine model of regional intracranial pressure was used to compare regional brain tissue pressure (RBTP) changes during expansion of an extradural temporal mass lesion. Measurements of RBTP were obtained by placing fiberoptic intraparenchymal pressure monitors in the right and left frontal lobes (RF and LF), right and left temporal lobes (RT and LT), midbrain (MB), and cerebellum (CB). During expansion of the right temporal mass, significant RBTP gradients developed in a reproducible pattern: RT > LF = LT > RF > MB > CB. These gradients appeared early, widened as the volume of the mass increased, and persisted for the entire duration of the experiment. The study indicates that RBTP gradients develop in the presence of an extradural temporal mass lesion. The highest RBTP was recorded in the ipsilateral temporal lobe, whereas the next highest was recorded in the contralateral frontal lobe. The RBTP that was measured in either frontal lobe underestimated the temporal RBTP. These results indicated that if a frontal intraparenchymal pressure monitor is used in a patient with temporal lobe pathology, the monitor should be placed on the contralateral side and a lower threshold for therapy of increased intracranial pressure should be adopted. Furthermore, this study provides further evidence that reliance on a single frontal intraparenchymal pressure monitor may not detect all areas of elevated RBTP.

Object National and international meetings, such as the Congress of Neurological Surgeons (CNS) and the American Association of Neurological Surgeons (AANS) meetings, provide a central location for the gathering and dissemination of research. The purpose of this study was to determine the publication rates of both oral and poster presentations at CNS and AANS meetings in peer-reviewed journals. Methods The authors reviewed all accepted abstracts, presented as either oral or poster presentations, at the CNS and AANS meetings from 2003 to 2005. This information was then used to search PubMed to determine the rate of publication of the abstracts presented at the meetings. Abstracts were considered published if the data presented at the meeting was identical to that in the publication. Results The overall publication rate was 32.48% (1243 of 3827 abstracts). On average, 41.28% of oral presentations and 29.03% of poster presentations were eventually published. Of those studies eventually published, 98.71% were published within 5 years of presentation at the meeting. Published abstracts were published most frequently in the Journal of Neurosurgery and Neurosurgery. Conclusions Approximately one-third of all presentations at the annual CNS and AANS meetings will be published in peer-reviewed, MEDLINE-indexed journals. These meetings are excellent forums for neurosurgical practitioners to be exposed to current research. Oral presentations have a significantly higher rate of eventual publication compared with poster presentations, reflecting their higher quality. The Journal of Neurosurgery and Neurosurgery have been the main outlets of neurosurgical research from these meetings.

✓ A new classification of head injury based primarily on information gleaned from the initial computerized tomography (CT) scan is described. It utilizes the status of the mesencephalic cisterns, the degree of midline shift in millimeters, and the presence or absence of one or more surgical masses. The term “diffuse head injury” is divided into four subgroups, defined as follows: Diffuse Injury I includes all diffuse head injuries where there is no visible pathology; Diffuse Injury II includes all diffuse injuries in which the cisterns are present, the midline shift is less than 5 mm, and/or there is no high- or mixed-density lesion of more than 25 cc; Diffuse Injury III includes diffuse injuries with swelling where the cisterns are compressed or absent and the midline shift is 0 to 5 mm with no high- or mixed-density lesion of more than 25 cc; and Diffuse Injury IV includes diffuse injuries with a midline shift of more than 5 mm and with no high- or mixed-density lesion of more than 25 cc. There is a direct relationship between these four diagnostic categories and the mortality rate. Patients suffering diffuse injury with no visible pathology (Diffuse Injury I) have the lowest mortality rate (10%), while the mortality rate in patients suffering diffuse injury with a midline shift (Diffuse Injury IV) is greater than 50%. When used in conjunction with the traditional division of intracranial hemorrhages (extradural, subdural, or intracerebral), this categorization allows a much better assessment of the risk of intracranial hypertension and of a fatal or nonfatal outcome. This more accurate categorization of diffuse head injury, based primarily on the result of the initial CT scan, permits specific subsets of patients to be targeted for specific types of therapy. Patients who would appear to be at low risk based on a clinical examination, but who are known from the CT scan diagnosis to be at high risk, can now be identified.

✓ The outcome of severe head injury was prospectively studied in patients enrolled in the Traumatic Coma Data Bank (TCDB) during the 45-month period from January 1, 1984, through September 30, 1987. Data were collected on 1030 consecutive patients admitted with severe head injury (defined as a Glasgow Coma Scale (GCS) score of 8 or less following nonsurgical resuscitation). Of these, 284 either were brain-dead on admission or had a gunshot wound to the brain. Patients in these two groups were excluded, leaving 746 patients available for this analysis. The overall mortality rate for the 746 patients was 36%, determined at 6 months postinjury. As expected, the mortality rate progressively decreased from 76% in patients with a postresuscitation GCS score of 3 to approximately 18% for patients with a GCS score of 6, 7, or 8. Among the patients with nonsurgical lesions (overall mortality rate, 31%), the mortality rate was higher in those having an increased likelihood of elevated intracranial pressure as assessed by a new classification of head injury based on the computerized tomography findings. In the 276 patients undergoing craniotomy, the mortality rate was 39%. Half of the patients with acute subdural hematomas died — a substantial improvement over results in previous reports. Outcome differences between the four TCDB centers were small and were, in part, explicable by differences in patient age and the type and severity of injury. This study describes head injury outcome in four selected head-injury centers. It indicates that a mortality rate of approximately 35% is to be expected in such patients admitted to experienced neurosurgical units.

The authors report an unusual case of cortical herniation into a chronic subdural hematoma (SDH). The patient was successfully treated with good outcome. A 4-month-old boy with a history of macrocrania and very large bilateral chronic SDHs underwent subduroperitoneal shunt treatment shortly after presentation. Eight months later he developed a new-onset seizure disorder, which was localized by electroencephalography to the right frontal region. Neuroimaging demonstrated the development of a focal herniation of the brain through a subdural membrane into the subdural space. The patient underwent a craniotomy to resect the seizure focus and the herniated cortex. The subdural shunt was subsequently replaced. After 2 years of follow-up, the patient remains free of seizures, is on no medication regimen, and is neurologically and developmentally normal. To the authors' knowledge, this is only the fourth report in the medical literature of cortical herniation through a chronic subdural membrane and the first in which successful treatment with a good outcome is described.

✓ A porcine model was used to study the regional intracranial pressure (ICP) differences caused by a frontal mass lesion. Intraparenchymal ICP monitors were placed in the right and left frontal lobes, right and left temporal lobes, midbrain, and cerebellum. A frontal epidural mass lesion was created by placing a balloon catheter through a burr hole into the right frontal epidural space. A computer was used to acquire data from all monitors at 50-msec intervals. The balloon was expanded by 1 cc over a period of 1 second every 5 minutes and maximum pressure immediately before and during expansion was determined for each balloon volume at each site. Prior to expansion of the mass, the morphology of the cerebellum pressure tracing was different from that seen in all supratentorial regions. Also, pressures in the midbrain, at baseline, were slightly but significantly lower than pressures in the frontal and temporal regions. During expansion of the mass, a pressure differential that increased as the size of the mass increased developed between intracranial regions. Furthermore, the regional pressures were found to vary in a consistent fashion expressed by the formula RF = LF > RT = LT > MB > CB, in which RF and LF are the right and left frontal lobes, RT and LT are the right and left temporal lobes, MR is the midbrain, and CB is the cerebellum. The study shows that an expanding epidural mass reproducibly results in a gradient of brain parenchymal pressure. This gradient results in parenchymal pressures that are significantly different in each region of the brain depending on the proximity of that region to the epidural mass. The results of this study have implications for clinical ICP monitoring and therapy.

✓ In this study, data were prospectively collected from 753 patients (111 children and 642 adults) with severe head injury and examined for evidence of diffuse brain swelling and its association with outcome. Diffuse brain swelling occurred approximately twice as often in children (aged 16 years or younger) as in adults. A high mortality rate (53%) was found in these children, which was three times that of the children without diffuse brain swelling (16%). Adults with diffuse brain swelling had a mortality rate (46%) similar to that of children, but only slightly higher than that for adults without diffuse brain swelling (39%). When the diagnosis of diffuse brain swelling was expanded to include patients with diffuse brain swelling plus small parenchymal hemorrhages (< 15 cu cm), these mortality rates were virtually unchanged.

✓ A No. 4 French fiberoptic catheter initially developed as an intravascular pressure sensor was incorporated into a system to be used as an intracranial pressure (ICP) monitor. Initially, a series of acute and chronic animal experiments carried out in the rabbit and pig, respectively, demonstrated the reliability and safety of the device. Subsequently, this new monitor was compared to a concurrently functioning ICP monitor in 15 adult and five pediatric patients. This clinical experience also confirmed the safety, accuracy, and reliability of the device. Since these initial studies, this monitor has been used to routinely measure ICP in a large number of adult and pediatric patients. The monitor has functioned well, and there have been no complications related to its use except for an occasional problem with breakage of the optic fiber as a result of patient movement or nursing maneuvers, which has been easily corrected by replacement of the probe. As nursing personnel and ancillary services have become familiar with this new monitor, breakage has not been a problem. This new device can be placed into the ventricular system, the brain parenchyma, or the subdural space, and appears to offer substantial advantages over other monitors presently in use.

✓ A series of 8814 head-injured patients admitted to 41 hospitals in three separate metropolitan areas were prospectively studied. Of these, 1906 patients (21.6%) were 14 years of age or less. This “pediatric population” was compared to the remaining “adult population” for mechanism of injury, admission Glasgow Coma Scale score, motor score, blood pressure, pupillary reactivity, the presence of associated injuries, and the presence of subdural or epidural hematoma. The relationship of each of these factors was then correlated with posttraumatic mortality. Except for patients found to have subdural hematoma and those who were profoundly hypotensive, the pediatric patients exhibited a significantly lower mortality rate compared to the adults, thus confirming this generally held view. This study indicates that age itself, even within the pediatric age range, is a major independent factor affecting the mortality rate in head-injured patients.