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Worldwide, cerebrovascular accidents (stroke) are the second leading cause of death and the third leading cause of disability.' Stroke, the sudden death of some brain cells due to lack of oxygen when the blood flow to the brain is lost by blockage or rupture of an artery to the brain, is also a leading cause of dementia and depression. (2) Globally, 70% of strokes and 87% of both stroke-related deaths and disability-adjusted life years occur in low- and middle-income countries. (3-5) Over the last four decades, the stroke incidence in low- and middle-income countries has more than doubled. During these decades stroke incidence has declined by 42% in high-income countries. 3 On average, stroke occurs 15 years earlier in--and causes more deaths of people living in low--and middle-income countries, when compared to those in high-income countries. (2) Strokes mainly affect individuals at the peak of their productive life. Despite its enormous impact on countries' socio-economic development, this growing crisis has received very little attention to date. The risk factors for stroke are similar to those for coronary heart disease and other vascular diseases. Effective prevention strategies include targeting the key modifiable factors: hypertension, elevated lipids and diabetes. Risks due to lifestyle factors can also be addressed: smoking, low physical activity levels, unhealthy diet and abdominal obesity. (6) Combinations of such prevention strategies have proved effective in reducing stroke mortality even in some low-income settings. (7,8) Furthermore, as most guidelines are based on high-income country data, uncertainty remains regarding best management of stroke of unknown type in low- and middle-income countries. For example, in low- and middle-income countries, 34% of strokes (versus 9% in high-income countries) are of haemorrhagic subtype and up to 84% of stroke patients in low- and middle-income countries (versus 16% in high income countries) die within three years of diagnosis. (2) Current guidelines for the management of acute stroke recommend a course of treatment based on the diagnosis of ischaemic stroke (versus haemorrhagic stroke) made using computed tomography (CT) scanners. In low-resource settings, CT scanners are either unavailable or unaffordable, forcing clinicians to make difficult clinical decisions, such as whether to anticoagulate patients or not, and to what level to control their blood pressure without a means of distinguishing between ischaemic and haemorrhagic stroke. These patient management challenges, combined with inadequate rehabilitation services, lack of preventive measures, as well as poor understanding of the possible unique risk factors associated with stroke in low- and middle-income countries, may account for the disproportionately large stroke burden borne by these countries. The reasons for the younger age of onset, higher rates of haemorrhagic subtype and higher case fatality, are unknown. …

Purpose To evaluate the efficacy of fractionated proton radiotherapy for a population of patients with benign cavernous sinus meningiomas. Methods and Materials Between 1991 and 2002, 72 patients were treated at Loma Linda University Medical Center with proton therapy for cavernous sinus meningiomas. Fifty-one patients had biopsy or subtotal resection; 47 had World Health Organization grade 1 pathology. Twenty-one patients had no histologic verification. Twenty-two patients received primary proton therapy; 30 had 1 previous surgery; 20 had more than 1 surgery. The mean gross tumor volume was 27.6 cm 3 ; mean clinical target volume was 52.9 cm 3 . Median total doses for patients with and without histologic verification were 59 and 57 Gy, respectively. Mean and median follow-up periods were 74 months. Results The overall 5-year actuarial control rate was 96%; the control rate was 99% in patients with grade 1 or absent histologic findings and 50% for those with atypical histology. All 21 patients who did not have histologic verification and 46 of 47 patients with histologic confirmation of grade 1 tumor demonstrated disease control at 5 years. Control rates for patients without previous surgery, 1 surgery, and 2 or more surgeries were 95%, 96%, and 95%, respectively. Conclusions Fractionated proton radiotherapy for grade 1 cavernous sinus meningiomas achieves excellent control rates with minimal toxicities, regardless of surgical intervention or use of histologic diagnosis. Disease control for large lesions can be achieved by primary fractionated proton therapy.

Summary box Chinese philosopher Laozi wrote, ‘Go to the people. Live among them. Learn from them. Start with what they know. Build on what they have’. This ancient counsel has modern-day application in the little-known development of primary healthcare (PHC) service delivery models and the integration of surgical care and anaesthesia into these models. Currently, five billion people lack access to safe, timely and affordable surgical and anaesthesia care; in low-resource settings, nine of ten people cannot access basic surgical services. Globally, 33 million individuals incur catastrophic expenditures resulting from surgical and anaesthesia care, and this number climbs to 81 million if indirect costs are included.1 The 2030 Agenda for Sustainable Development, approved by …

Cobb syndrome is a rare clinical entity that includes the combination of a vascular skin nevus and an angioma in the spinal canal present at identical dermatomal level(s) (cutaneomeningospinal angiomatosis). To date, 38 cases have been reported, only 18 of which are in adults (> 18 years of age). The majority of these cases have been described in the era predating current neuroimaging techniques, and most authors have assumed that each case involves similar vascular pathology. This report highlights 2 patients presenting with similar thoracic cutaneous vascular nevi yet with markedly differing spinal vascular pathology. A 29-year-old man presented with cutaneous hemangioma and a progressive paraparesis and paresthesia of the lower extremities. A 20 × 20–cm port-wine stain over his right upper midback (T6–10) correlated precisely with MR imaging that demonstrated an enhancing epidural mass between T-6 and T-10 causing compression of the cord and cord edema. A 34-year-old man also presented with progressive myelopathy and a 15 × 20–cm port-wine stain within the same dermatomal region as a Type III spinal arteriovenous malformation. Workup for each patient included pre- and postoperative contrast-enhanced MR imaging with vascular sequencing and spinal angiography. The first patient was treated with bilateral laminectomy at the T6–10 levels, with significant postoperative improvement in motor strength. The second patient underwent coil embolization of an intranidal aneurysm, with follow-up embolization 8 years later. Cobb syndrome is an unusual entity in the adult population and should be considered when there is a constellation of cutaneous manifestation and underlying neurological deficit. The vascular skin nevus associated with Cobb syndrome is accompanied by a wide variety of vascular pathologies.

Cerebral AVMs are known to be a source of intracranial hemorrhages and epileptic seizures. Their natural history indicates approximately 15% mortality and 35% morbidity over a 15-year period. This significant mortality and morbidity mandates a need for satisfactory treatment of this entity, ideally by elimination of AVMs. Microsurgical resection, endovascular embolization and radiosurgery (irradiation) are the three effective modes of treatment currently available. However, no objective criteria have been established for which mode(s) of treatment should be selected for individual patients with AVMs. Considering the complexity of AVMs and variable conditions of individual patients, neurosurgeons, intravascular interventionalists and radiosurgeons must make their own decisions on how to treat each patient based on their experience. In practice, treatment of small AVMs in non-functional areas is favored equally by each of these specialists, while they tend to avoid treatment of large AVMs, particularly those in functional areas of the brain. The authors report the surgical intervention of large AVMs, including those located in functional areas of the hemisphere by special techniques. One can demonstrate AVM compartments by using angiography and with the aid of color Doppler ultrasonography, each compartment can be outlined and dissected individually until all the compartments are isolated without causing any damage to the surrounding brain and the entire AVM is rendered shrunken and then removed. The concept of compartmental treatment of AVMs may be applied in the future to radiosurgery and intravascular embolization of large AVMs.

OBJECTIVE This study evaluated proton beam irradiation in patients with acoustic neuroma. The aim was to provide maximal local tumor control while minimizing complications such as cranial nerve injuries. METHODS Thirty-one acoustic neuromas in 30 patients were treated with proton beam therapy from March 1991 to June 1999. The mean tumor volume was 4.3 cm3. All patients underwent pretreatment neurological evaluation, contrast enhanced magnetic resonance imaging, and audiometric evaluation. Standard fractionated proton radiotherapy was used at daily doses of 1.8 to 2.0 cobalt Gray equivalent: patients with useful hearing before treatment (Gardner-Robertson Grade I or II) received 54.0 cobalt Gray equivalent in 30 fractions; patients without useful hearing received 60.0 cobalt Gray equivalent in 30 to 33 fractions. RESULTS Twenty-nine of 30 patients were assessable for tumor control and cranial nerve injury. Follow-up ranged from 7 to 98 months (mean, 34 mo), during which no patients demonstrated disease progression on magnetic resonance imaging scans. Eleven patients demonstrated radiographic regression. Of the 13 patients with pretreatment Gardner-Robertson Grade I or II hearing, 4 (31%) maintained useful hearing. No transient or permanent treatment-related trigeminal or facial nerve dysfunction was observed. CONCLUSION Fractionated proton beam therapy provided excellent local control of acoustic neuromas when treatment was administered in moderate doses. No injuries to the Vth or VIIth cranial nerves were observed. A reduction in the tumor dose is being evaluated to increase the hearing preservation rate.

The net discount rate, measured as the average difference between the nominal wage growth and the nominal interest rate over the available historical period, is often used by forensic economists to determine the present value of future earnings losses. The correct value to use for the net discount rate has, in recent years, been a topic of controversy and extensive discussion among practitioners. A number of studies in the literature have advocated the use of net discount rates close to zero, see Pelaez (1995). The use of this “total offset” method is based on a calculation of the average net discount rate over time using the return on 91-day treasuries as the nominal interest rate. Critics of the total offset method argue that it yields a distorted measure for the net discount rate owing to a shift in its mean during the latter part of 1979, see Gamber and Sorensen (1993), Gelles and Johnson (1996), Johnson and Gelles (1996), and Hovarth and Sattler (1997). Specification of the breakdate during the last quarter of 1979 was prompted by visual inspection of the net discount rate time plot, and attributed to structural change caused by the announced change in the Federal Reserve Bank’s operating procedure. Therefore, all studies mentioned above propose using the average net discount rate based on the post-1979 sample. The average net discount rate based on the post-1979 sample is larger than zero, and hence interpreted as evidence against the use of the total offset method. In particular, Johnson and Gelles (1996) suggest that it may be more appropriate to use the average net discount rate based on a smaller sample period, specifically the average net discount rate based on the most recent 10-year period. Using the testing methodology of Perron (1989), Gamber and Sorenson (1993), find that the net discount rate should be modeled as a stationary process with a change in the mean when the break is pre-specified during the last quarter of 1979. Perron’s (1989) methodology is open to some statistical problems in that he assumes the break-date to be exogenous to the data generating process, and therefore requires the practitioner to pre-specify the break-date. Christiano (1992) and Zivot and Andrews (1992) among others have pointed out that Perron’s (1989) methodology does not account for pretest examination of the data implicit in the specification of the break-date. That is, the choice of the break-date is inevitably correlated with the data and so the pre-specified break-date incorporates some prior information about the data (in this case a visual inspection of the data), while the testing procedure does not account for this. The purpose of our analysis is to determine whether there is evidence of a shift in the mean once the break-date is no longer pre-specified. Following Gamber and Sorensen (1993), quarterly data on the growth rate in weekly earnings and the nominal interest rate on 91-day T-Bills over the

No abstract available.

Over the past decade, the concept of surgical care as a population-based, affordable, and globally relevant issue has gradually begun to emerge.[24,28,34,37] The facts are startling: more people die each year due to the inability to access surgical care than from human immunodeficiency virus/acquired immune deficiency syndrome (HIV/AIDS), tuberculosis, and malaria combined.[6] The highest incidence results from (in descending order) accidental trauma (bone and soft-tissue injuries), tumors, obstetrical complications (including obstetrical fistula), cataracts and glaucoma, perinatal conditions and congenital anomalies, male circumcision (prevention of HIV transmission) and a large group (19%) under the heading of “Other,” which include a variety of diagnoses such as hernia, gall bladder disease, infections requiring surgical care, etc.[4,6] However, the global burden of disease (GBD) associated with surgical and obstetrical care has yet to be adequately defined; current numbers are likely to be artificially low.[27,36] While the total volume of actual surgical cases can be tallied, the unmet surgical need is only beginning to be measured.[29] It is not without reason that surgery has been termed the “neglected stepchild” of global public health and the “neglected specialty in the current global health arena.”[7,8] Historically, the primary barrier to developing surgical services has been the (mis)perception that surgery is overly expensive for the majority of lower and middle income countries (LMICs).[3] However, the World Bank published the 2nd edition of Disease Control Priorities in Developing Countries (DCP, 2006), which provided the first clear economic evidence that surgical care could be a cost-effective strategy under certain circumstances when compared with other types of care, such as antiretroviral medications, vaccinations, and other primary treatments. This economic impact was calculated on the basis of Disability Adjusted Life Years (DALYs), which is the sum of Years of Life Lost (YLL) plus the Years Lost due to Disability (YLDs) or simply: DALY = YLL + YLD. The purpose of surgery, however, is to alleviate or mitigate against certain physical conditions and the resultant “DALYs averted” reflects the reduction in calculated DALY as a consequence of the timely institution of appropriate surgical care. Surgical conditions account for 11% of global DALYs lost each year, with LMICs carrying the greatest burden; Southeast Asia plus Africa alone, accounted for 54% of DALYs in 2004.[6,9] Emergency and essential surgical care is increasingly recognized as a critical element to improving primary health care delivery. In the World Health Report 2008—Primary Health Care (Now more than Ever), the World Health Organization (WHO) included Surgery for the first time within the Primary Healthcare Sphere of Care.[22,35] This report emphasized the creation of primary care teams responsible for defined populations with access to all aspects of care, which was not splintered by economic concerns or differences. While inserting one word on an organizational chart appears to be a small step, it was a huge leap forward that required years of continual effort. Additionally, WHO has made surgical care a priority.[1,20] The Emergency and Essential Surgical care (EESC) of the WHO, has been active in the Global Initiative for Emergency and Essential Surgical Care (GIEESC), a forum of surgical experts. EESC has published the volume Surgical Care at the District Hospital (SCDH) in seven languages and produced the Integrated Management of Emergency and Essential Surgical Care (IMEESC) toolkit, a Compact Disc that contains the SCDH, a long list of best-practice protocols (including disaster management), multiple point-of-contact posters, and a number of instructional videos. Ongoing research within EESC includes a large database of surgical hospital capacity throughout the developing world (>700), capacity building through educational programs, and periodic follow-up of existing programs. Within the WHO, other areas of relating to surgery include Violence and Injury Prevention, Maternal and Child Health, HIV/AIDS (male circumcision), and transplantation. Surgery is credited with providing a critical role in achieving the United Nations Millennium Development Goals (MDGs) and is most closely involved with numbers 4, 5, and 6.[23] Although most directly linked to these MDGs, surgical care also indirectly, but significantly contributes to MDG 1: The eradication of poverty and hunger. This is due to the fact that restoring health to the man who is a primary provider (such as repairing an inguinal hernia so that he can return to work) and/or the woman who provides for the home and children (such as relieving obstructed labor or repairing a vesico-vaginal fistula), greatly reduces economic loss and/or emotional hardship.

This paper presents a neurophysiologic model of effective public service advertisements (PSAs) and reports two experiments that test the model. In Experiment 1, we show that after watching 16 PSAs participants who received oxytocin, compared to those given a placebo, donated to 57% more causes, donated 56% more money, and reported 17% greater concern for those in the ads. In Experiment 2, we measured adrenocorticotropin hormone (ACTH) and oxytocin levels in blood before and after participants watched a PSA. As predicted by the model, donations occurred when participants had increases in both ACTH and oxytocin. Our results indicate that PSAs with social content that cause OT release will be more effective than those that do not. Our results also explain why some individuals do not respond to PSAs.

Despite fundamental changes in both the overall economic climate, and the financial markets in specific, both the academic literature and the majority of actual earnings loss calculations encountered by the authors continue to reference a "net" discount rate figure of between 0 and 2% (Brookshire and Slesnick, 1993). The rationale customarily cited for utilizing these "minimal" discount figures is the historical relationship between the relevant nominal interest rates and earnings growth. As is indicated in the following critical examination, however, continued production of these results is becoming increasingly dependent on selectively restricting the studied data sets, limiting the depth of the statistical analysis, and disregarding the structural alterations that have taken place in the macroeconomic environment in the post-WW II period. Once these constraints are removed, substantially higher "net" discount figures are produced---ones which significantly alter the results of future loss estimates. I. Data Selection Mathematically, the actual computation of a "net" interest rate is a relatively straight forward process. It consists of a simple subtraction of some relevant pecuniary measure of the change in the economic variable representing the loss factor, such as profits, gross receipts or wages, from a composite market interest rate over some comparable period of time. Ideally, a measure of the damaged or lost pecuniary value which most closely approximates that forgone by the injured party is chosen. As an example, in a forgone earnings action, the actual wage history of the individual or his/her relevant cohort would be the preferable choice. In the absence of specific cohort data or in instances where an insufficient individual earnings history exists, the analysis is often based on average earnings movements for the general population. Because of its broader applicability, the general data set approach is also the one most often chosen for discount rate research. The specific earnings series most often seen in the literature (Bonham and Sumner, 1992; Lawless and Male, 1994) and, convention, chosen by the authors for this study is average hourly wages in

In a recent edition of the Journal of Forensic Economics, the results of two informative surveys were published. 1 The first examined methodological approaches currently used by the members of the National Association of Forensic Economics (NAFE) when acting as experts in tort litigation. The second presented their views on the topics of ethical behavior and qualifications. While both of these studies provided significant insights into the parameters within which forensic economists work, there is another, equally important, determinant of the economist’s actions in tort litigation that needs to be examined--the role of attorneys. The attorney’s impact on the performance of the economic expert is occasioned through control of both the hiring process and the testimony which is entered into evidence. These decisions are, in turn, predicated to a large extent on the attorney’s expectations for, and views of, the capabilities of the experts they hire and the attorney’s own understanding of what economics can, and cannot, contribute to winning a case. In an attempt to gain some perspective on the implications of these interactions between the attorney and the economist, the authors undertook a survey of attorneys in the summer of 1993, concerning the process they use for selecting economic experts, their experiences with these experts and their own views on ethics. Questionnaires were mailed to a sample of 1,100 trial attorneys licensed to practice law in Iowa, Illinois, Missouri, New York and New Jersey. 2 These states were selected on the basis of the authors’ geographical location, access to trial lawyer mailing lists and familiarity with the tort framework in these jurisdictions. Allowing for undeliverable questionnaires, 238, or 22.6%, of a potential 1,054 surveys were returned. This rate of return is close to that received in recent surveys of forensic economic practitioners conducted by Brookshire and Slesnick (1991 and 1993) and, indicated in their latest article, "is considered relatively high for a mail questionnaire". Obviously the relevance of the responses to the questions at hand depended upon the attorneys having had some experience with the use of economic experts. Unfortunately, there was no way that this specific subset of attorneys could be identified in advance from the initial lists of trial lawyers possessed by the authors. As a consequence, questionnaire recipients had to be specifically directed to fill out the survey form "only if they had used an

Neurosurgical treatment of spontaneous intracerebral hemorrhage (ICH) is controversial, with a lack of evidence-based guidelines contributing to the high variety of treatments. In our study we examine the outcome and complication from use of intralesional tissue plasminogen activator (IL tPA).Patients who have been treated with IL tPA for spontaneous ICH were reviewed retrospectively. We compared clot sizes before and after tPA infusion, and outcome based on the modified Rankin score.Nine patients received IL tPA during the period 1999-2009. No immediate complications with use of IL tPA were found. There was a statistically significant volume reduction in clot sizes on computed tomography. Four patients recovered to independent functional status. Three patients were discharged to SNF, and two patients died as a result of ICH. Our results appear to demonstrate superior outcome to supportive management and no worse result than surgical management.It appears a subset of ICH patients benefits from use of IL tPA. This study demonstrates that IL tPA use is safe and has the potential to improve outcome compared to conservative management without the risk of surgical complications. Our patient size is small, and larger prospective studies are needed to provide solid guidelines for management of ICH.

Introduction: Neurosurgical treatment of spontaneous intracerebral hemorrhage (ICH) is controversial, with a lack of evidence-based guidelines contributing to the high variety of treatments. In our study we examine the outcome and complication from use of intralesional tissue plasminogen activator (IL tPA).

No abstract available.

No abstract available.

Hydrocephalus has amazed and challenged clinicians throughout the history of medicine. In reviewing the treatment of hydrocephalus, the integral relationship between basic science and therapy is reaffirmed. As we embark into a new millennium, it is appropriate to reflect on the past studies of this disorder, review various attempted and currently used, and finally speculate on possible future directions in its treatment.

This study compared mandibular distraction and vertical ramus osteotomy in terms of their effectiveness at increasing access to the cranial base and distal internal carotid artery. Five fresh-frozen cadavers were used to obtain a total of ten cranial base exposures. The following two techniques were evaluated on each of the ten exposures: (1) anterior distraction of the mandible without violation of the temporomandibular joint capsule, and (2) vertical ramus osteotomy of the mandible with distraction of the proximal and distal segment. The neutrally positioned mandible with the condyle seated in the glenoid fossa served as the control. The area of surgical access defined by bony and cartilaginous landmarks was determined for each technique using the nondistracted control as a baseline.The vertical ramus osteotomy group provided greater increase in surgical access with approximately a 99.64 % increase compared with the control and a mean area of exposure of 14.653 cm(2). Mandibular distraction provided only a 28.32 % increase with a mean area of 9.252 cm(2). The control or nondistracted baseline mean area of exposure was 7.214 cm(2). Vertical ramus osteotomy significantly increased access to cranial base vascular lesions with minimal morbidity. It afforded greater and more reliable access than that achieved by the mandibular distraction technique. The procedure can be completed rapidly with no additional skin incisions.

Spinal hydatidosis is an uncommon manifestation of the parasite Echinococcus, affecting fewer than 1% of patients with hydatid disease. The authors report on a 34-year-old Turkish woman who presented with recurrent primary spinal hydatid disease. The patient originally presented with progressive numbness and paraparesis that was reversed after T5–6 laminectomy and cyst removal. Pathological findings indicated parasitic infection and she underwent treatment for cysticercosis. Nevertheless, she returned 4 years later with back pain, numbness, and monoparesis. Neuroimaging studies revealed spinal cord compression with multiple cysts that were again resected. Pathological findings were consistent with Echinococcus. Although this disease is uncommon, particularly in North America, the authors conclude that spinal hydatidosis should be considered in the differential diagnosis of any patient who has lived or traveled within endemic areas and who presents with spine lesions and cord compression. The authors review the literature pertaining to the epidemiological features, presentation, diagnosis, neuroimaging characteristics, recommended treatments, and overall prognosis of spinal hydatidosis.

No abstract available.

Cerebral vasospasm remains the principal cause of morbidity and mortality following successful clipping of intracranial aneurysms. Current management often requires subjective judgments concerning presumed abnormalities of cerebral blood flow. In this study, a combined intracranial pressure (ICP)-laser Doppler flowmetry (LDF) fiberoptic probe that permits continuous monitoring of local cerebral blood flow (lCBF) was used in the postoperative management of 20 aneurysm patients. Using this probe, lCBF was simultaneously recorded and integrated on a real time basis with other physiological parameters, including ICP, systemic arterial pressure, pulmonary arterial pressure, central venous pressure, and pulse oximetry. The combined probe also provided the ability to obtain precise and detailed information concerning the presence or absence of cerebral autoregulation and CO2 vascular reactivity, and allowed calculation of the cerebral vascular resistance. Continuous monitoring of lCBF in this manner complemented by transcranial Doppler and angiographic data permitted early detection of cerebral ischemia, helped to differentiate cerebral ischemia from edema and hyperemia, was useful in titrating blood pressure and fluid management, provided direct feedback about the effectiveness of instituted therapies, and determined early on when medical management was of no avail and that interventional neuroradiology was indicated. Evidence is presented that the presence of angiographic vasospasm and increased velocities on TCD do not always correlate with ischemia in the microcirculation and that direct measurements of lCBF are often at variance with calculations of cerebral perfusion pressure (CPP).

BACKGROUND The treatment of bacterial intracranial aneurysms include long-term antibiotic therapy and surgical clipping or resection. Direct surgical approaches to these aneurysms are often complicated by their peripheral location. METHODS We report the use of a computerized tomography (CT) localized stereotactic craniotomy for the excision of a ruptured peripheral bacterial intracranial aneurysm. RESULTS The Leksell Steiner-Lindquist microsurgical guide, with its fiberoptic helium-neon laser, allowed for rapid isolation of the distal aneurysm with minimal cerebral dissection. Since the inflammatory lesion was well demonstrated on postcontrast CT scan, this modality, rather than angiography, was used for localization. CONCLUSIONS In the future, stereotactic craniotomy may facilitate aggressive surgical therapy for infectious aneurysms previously thought not suitable for direct operative approach.

✓ Syrinx shunts to the spinal subarachnoid space are likely to fail if the cerebrospinal fluid pathways rostral to the syrinx are blocked. To bypass obstructions at or below the level of the foramen magnum, a technique was developed for shunting the syrinx to the posterior fossa cisterns, termed “syringocisternostomy.” Syrinxes were shunted to the cisterna magna in two patients with spinal arachnoiditis and to the cerebellopontine angle cistern in four patients with Chiari I malformations. There was symptomatic improvement and collapse of the syrinx in each case, with no complications or recurrences over a follow-up interval of 14 to 27 months (average 20.3 months). The surgical technique and results of treatment are described.

The treatment of syringomyelia includes many surgical options. We report a retrospective study of 65 patients with cavitary lesions of the spinal cord in whom the results of magnetic resonance imaging were used to develop specific treatment strategies. Intramedullary cavities were classified into three general types: 1) communicating syrinxes, which occurred with hydrocephalus and were anatomically continuous with the 4th ventricle (9 patients); 2) noncommunicating syrinxes, which were separated from the 4th ventricle by a syrinx-free segment of spinal cord (42 patients); and 3) atrophic syrinxes, which occurred with myelomalacia (14 patients). Noncommunicating syrinxes were further subdivided according to type: Chiari II malformations with hydrocephalus (5 patients), Chiari I malformations without hydrocephalus (11 patients), extramedullary compressive lesions (12 patients), spinal cord trauma (6 patients), intramedullary tumors and infections (6 patients), and multiple sclerosis (2 patients). Of the 65 patients, 39 underwent surgical treatment for progressive symptoms. Syrinxes occurring with hydrocephalus were treated empirically with a ventriculoperitoneal shunt. Excellent results were achieved in 7 of 7 patients with communicating syrinxes and in all 5 patients with Chiari II malformations. Two approaches were used in the treatment of syrinxes occurring with Chiari I malformations: Posterior fossa decompression improved symptoms but did not reduce syrinx size in 2 of 3 patients. In the third patient and in 3 patients who were not treated with decompression, shunting from the syrinx to the cerebellopontine angle cistern collapsed the cavity and resolved symptoms over the interval of follow-up (average follow-up, 1.5 years). Excision of extramedullary obstructions at the rostral end of noncommunicating syrinxes resulted in collapse or disappearance of the cavity in 6 of 7 patients. The remaining patient was treated effectively by a syringocisternal shunt. In all 4 patients with posttraumatic syringomyelia, good results were achieved by a spinal or syringocisternal shunt. Syrinxes associated with intramedullary masses were managed by biopsy or excision of the causal lesion and appropriate adjunctive therapy (6 patients). Patients with atrophic syrinxes were not operated upon except to relieve symptoms referrable to the causal lesion (4 patients). Recurrent syrinxes were not encountered in the 35 surviving patients over an average follow-up of 2.5 years. It is concluded that syringomyelia is a complex pathological disorder with several mechanisms of pathogenesis that requires a number of different treatment strategies.

The movement of Evans blue dye (EBD) through the central canal of the spinal cord was investigated in rats. Following injection into the dorsal columns at T5–6, the marker moved centripedally into the central canal and drained rostrally, to exit through the outlets of the fourth ventricle within 90 min. A similar pattern of clearance was produced by freeze-lesioning the dorsal columns and injecting EBD intravascularly. When the marker was injected into the lateral ventricles, the cisterna magna, or the lumbar subarachnoid space, it failed to enter the central canal. Taken together, these findings are consistent with an intraluminal flow of fluid that moves in a rostral direction through the central canal of the spinal cord in rats.

The pathogenesis of syringomyelia is incompletely understood. Since the condition is known to occur in association with hindbrain malformations and a variety of other lesions that occur at the level of the foramen magnum, attempts have been made to explain its development hydrodynamically. According to Gardner (Gardner et al. 1957; Gardner and Goodall 1950; Gardner and McMurry 1976), syringomyelia is caused by mechanical obstruction of the outlets of the fourth ventricle which results in a redirection of the cerebrospinal fluid (CSF) pulse wave into the central canal. The caudal focusing of the pulse wave presumably distends the central canal and leads to a net accumulation of fluid that may be confined to the lumen of the canal (hydromyelia) or may dissect into the paracentral tissues if the ependymal lining ruptures (syringohydromyelia).

ADIATION, received at its invention as a great novelty, rapidly demonstrated that its unrestricted use translated into catastrophic complications, mostly in the form of cancers. Over time, limits were imposed to reduce exposure of personnel and surrounding body structures, yet deliver an appropriate dose to a specific target to achieve a particular goal. This is now achieved with modern forms of radiation by complex algorithms and highpowered computer technology. The paradox remains that this potentially harmful energy source may be harnessed and with careful planning be an effective instrument in the treatment of various tumors, yet may still have unwanted, delayed consequences. In this month’s topic of Neurosurgical Focus, we explore current radiation treatment of benign intracranial tumors. The first article is a review of the current management strategies of various benign tumors using state of the art radiation methods, highlight some of the differences in these techniques, and finally demonstrate how these can be complementary to the surgical treatment of these tumors. Gopalan and Lee explore the use of stereotactic radiosurgery (primarily Gamma Knife) and CyberKnife, respectively, in the treatment of craniopharyngioma. Pearson describes the evolution that treatment of atypical meningioma has undergone over the past several years with changing diagnostic criteria. Romanelli reviews radiation for hypothalamic hamartomas and Ghostin,e the treatment of pituitary adenomas. Juxtaposed to these fine articles describing the benefits of radiation therapy is the excellent, yet sobering, contribution of Umansky documenting in graphic detail the consequence of radiation therapy, given in the past for relatively benign conditions. Although these radiation-induced tumors are, thankfully, not common in a typical neurosurgical practice, the consequences of even “benign” doses of radiation may, at some point in the future, result in unacceptable outcomes. Will we be seeing more of these tumors in the future as we refer more patients for radiation? This notion is highlighted by the critique and comments of Mathiesen.

Historically, radiation therapy has been used extensively in the treatment of malignant and aggressive intracranial tumors, and the importance of its role has been repeatedly verified by prolonged patient survival rates and increased tumor control. As more modern capabilities are employed in surgery and radiotherapy, attention is being directed to the utility of radiation as either primary or secondary treatment of benign tumors. Specifically, primary treatment encompasses irradiation of small benign tumors without biopsy confirmation of tumor type; secondary treatment involves postoperative radiation therapy, with the possibility that less-aggressive tumor resection may be performed in areas that have a higher probability of resultant neurological deficit. Current literature suggests that this is not only a possible treatment strategy, but that it may be superior to more radical resection in some cases, for example, in vestibular schwannomas and meningiomas. This article provides an overview of factors to consider in the use of radiation therapy and reviews the relationships between radiation and surgery, notably the unique complementary role each plays in the treatment of benign intracranial tumors. (DOI: 10.3171/FOC/2008/24/5/E2)

✓ The treatment of pituitary tumors has progressed into a multidisciplinary approach that involves neurosurgeons, radiation oncologists, and endocrinologists. This has allowed improved outcomes in treatment of pituitary tumors due to a combination of surgical, medical, and radiation therapies. In this study, the authors review the role of radiation therapy in the treatment of pituitary adenomas.

No abstract available.

The major reason for the existence of public agencies, such as the Food and Drug Administration (FDA), is the provision of societal protection. The scientific basis for resource allocation to and by these programs is found in the economic theory of cost-benefit (CB) analysis. This theory tells us that an efficient allocation is assured when society's willingness to pay for reducing risk is compared with the cost of obtaining these reductions. Unfortunately, many of these agencies, because of congressional mandates or other internal reasons, either do not conduct CB studies or, if they do, they do not measure benefits and costs at their true levels [Van Houtven and Cropper, Resources, Winter 1994]. As a fail-safe position, the courts have been charged with providing a deterrence backup through the availability of tort litigation. An example of a regulatory area relying on agency and judicial oversight has been the establishment of safety protocols to insure that blood products are free from transmittable diseases. Despite the obvious value to the public of insuring a safe blood supply, neither the FDA nor the courts have fully utilized the arsenal of economic tools available to them to assure this end. A major case in point is the spread of the HIV virus. In discussing the FDA's decision in 1989 not to license the HIV-antigen test which could have identified additional HIV-contaminated blood, one official noted [Solomon, Plasmapheresis, October 1989, p. 242] that "in reaching these conclusions, the agency made no use of cost-benefit analysis as cost is not a component of safety or efficacy assessments." This approach by the FDA, in conjunction with the acceptance by the courts of an argument that initially shielded the blood industry from strict liability in instances of transmission-borne disease, resulted in a market failure that these researchers believe is at least partially responsible for the currently identified 6,000 cases of transfusion-associated AIDS (TA-AIDS) in this country. It is the authors' contention that the correct application of the existing economic theory could have significantly lessened the risk to the public of TA-AIDS. Given that HIV is not tikely to be the last blood-borne virus that will arise to threaten national health, it is essential that a preventative framework based on sound, economic principles be instituted to avoid the possible reccurrence of this episode. A key element in this program must be the deterrence incentives provided by the courts through the assignment of pecuniary penalties. In an attempt to measure this deterrence effect, the authors are currently engaged in an analysis of court-awarded damages stemming from the recent relaxation of the blood-shield defense. This research is an extension of a recent costbenefit study of the FDA-sanctioned testing protocol [Gelles, Journal of Policy Analysis and Management, Summer 1993] and Eckert's examination of the implications of eliminating the laws which have protected the blood industry from strict liability [San Diego LawReview, Spring 1992].

The authors discuss the implementation of a minor in economics and the benefits that result to both students and the department.

Hindbrain lesions that distort or compress the cervicomedullary junction are commonly associated with syringomyelia. As a basis for discussing pathogenetic mechanisms, the upper end of the central canal of the spinal cord was examined histologically in six aborted fetuses and 14 adults dying of natural causes; the results were correlated with magnetic resonance images in 40 normal subjects. The central canal of the medulla, which extends from the cervicomedullary junction to the fourth ventricle, was found to migrate dorsally, elongate in dorsoventral diameter, and dilate beneath the tip of the obex to form a large, everted aperture. This opening communicates directly with the subarachnoid space through the foramen of Magendie and is indirectly continuous with the main body of the fourth ventricle. In adults, the aperture of the central canal is located approximately 1.0 cm below the tela choroidea inferior and 3.5 cm below the midpoint of the fourth ventricle. Analysis of magnetic resonance imaging scans in 45 patients with syringomyelia and simple hindbrain lesions revealed two patterns of cavity formation: 1) lesions that obstructed the upper end of the central canal or its continuity with the subarachnoid space produced a noncommunicating type of syringomyelia; and 2) lesions that obstructed the basilar cisterns or the foraminal outlets of the fourth ventricle produced a communicating type of syringomyelia (hydromyelia) in association with hydrocephalus. Evidence is presented that syrinxes occurring with hindbrain lesions are not caused by a caudal flow of cerebrospinal fluid from the fourth ventricle into the central canal of the spinal cord.

Fourteen newborn ( 24 hours). Recipient animals received cyclosporine 48 and 24 hours before the operation and daily after the operation on a gradually reducing daily protocol. Recipients were also given pulse doses of methylprednisolone (100 mg/kg) and azathioprine (3 mg/kg) once a week, the dosage schedule being gradually reduced and azathioprine discontinued as recipients became long-term survivors (>60 days). Seven recipients had radionuclide left ventriculography for measurement of left ventricular ejection fraction from 1 to 4 months postoperatively. Ejection fractions at 1 month in two recipients were 35 % and 57 %, and at 2 months the ejection fraction in one recipient was 58%. Serial ejection fractions from 1 to 4 months postoperatively in four recipients averaged 50 %, 58 %, 45 %, and 45 %. Survival in days among the 10 recipients was 24, 32, 44, 47, 60, 60, 78, 90, 120, and 165. Average survival was 72 days. There were no significant infections. Most animals showed mild-to-moderate subacute and chronic graft rejection at autopsy. One host showed no gross or microscopic graft rejection at autopsy on postoperative day 47. Tumor was not observed. These data suggest that long-term survival may be feasible for newborn recipients of cardiac xenografts with cyclosporine therapy and limited supplemental immunosuppression.

The creation of traditional family patterns and the transformation of these patterns into stereotypical nuclear study models has spawned a prolific amount of literature on individual happiness, psychological gratification and emotional self-sufficiency. The fragmentation of these family models through divorce has resulted in a breakdown of family function and a disassociation of its members. While some attention has been paid to the economic impact of divorce on the nuclear family, little concern has been shown regarding the economic ramifications on the post-divorce family unit. It is hypothesized that in the post-divorce period, the nuclear has been reshaped or reformed into an extended family. The dissolution-fragmentation process changes the environment in which the family continues to function. It is this extended family and the environment which sustains it that presents the focus of our inquiry. Although we do not disagree that the nuclear family is the predominant model as established by former st...

Vasogenic brain oedema is a concomitant of a wide variety of central nervous system lesions that have in common a disturbance of the blood-brain barrier permeability. Although it is well established that the formation and spread of this extracellular type of oedema is influenced directly by variations of systemic arterial pressure, the consequences of these events on local cerebral blood flow are not known. In the current experiments, vasogenic brain oedema was produced in rats by cold-injury lesions, and local cerebral blood flow measurements were made using a technique of 14C-antipyrine quantitative autoradiography under pharmacologically controlled conditions of hypertension, hypotension, and normotension. Evidence is presented that the formation and spread of vasogenic brain oedema is accompanied by the development of a congruent zone of decreased local cerebral blood flow, and that the magnitude of this field of oedema/ischaemia is a direct function of systemic arterial pressure. These findings may have important clinical implications.

In the mercuri- and halo-cyclizations of PGF 2 α methyl ester and its 11,15-bis(α-ethoxyethyl)-ether (or other protected forms) the exo -PGI 1 derivative predominates independent of reagent and degree of protective of the PGF 2 α sample used. Diastereomerically pure samples of exo - and endo -PGI 1 and prostacyclin (PGI 2 ) were prepared. PGI 0 epimers were prepared: catalytic hydrogenation of PGI 2 Me ester provides exclusively the endo isomer. PGI 2 methyl ester was found to be stable to extensive chromatography on silica, and to storage for at least a year in anhydrous ethanol at −20°C. At pH 7.4 in 2:1 H 2 O:EtOH, the ester has a half-life in excess of 5 hr at 25°C. A reproducible small scale (0.4–3 mg) synthesis of prostacyclin uses a modification of Whittaker's iodocyclization followed by DBN treatment. This procedure, developed with 15- 3 H-PGF 2 α, proved widely applicable to PGF 2 α analogs and diastereomers. The following prostacyclins (in the Me ester and Na salt forms) bearing the 5-en-6-yl ether unit were prepared in this way: ent -PGI 2 , rac -PGI 2 , 15-epi-PGI 2 , ent -15-epi-PGI 2 , 11-epi-PGI 2 , 8,9,12-epi-PGI 2 , E -PGI 2 , 13,14-dihydro-PGI 2 , and 13,14-dihydro-15-epi-PGI 2 . NMR comparisons for the methyl esters reveal that of the resonances (H-5,9,11,15) that appear at δ4.0±0.6 ppm, the most deshielded is H-9 so long as the 5,6-olefin is Z . The 8 R ,9 S -6,9-oxido- Z -5,6-ene unit is most readily characterized by its strong positive dichroic absorption at 210–230 nm. CD spectroscopy not only serves to confirm the presence of this unit in analogs, but also can be used for quantitative analysis of PGI 2 solutions and for monitoring the rate of hydrolytic cleavage of these enol ethers.

With the rising number of divorces during the past decade serious questions are being raised in the literature concerning the future of marriage and the impact of marital dissolution on members of the family. Unfortunately social scientists have continued to examine the consequences of divorce only on a singular and somewhat sporadic basis. It is time that a concerted effort was undertaken to examine the consequences of divorce. This paper proposes that a National Center for the Study of Divorce be established and presents a possible organizational structure for such a body.