Late rapid deterioration after endoscopic third ventriculostomy: additional cases and review of the literature

Journal ArticleObject. Late rapid deterioration after endoscopic third ventriculostomy (ETV) is a rare complication. The authors previously reported three deaths from three centers. Three other deaths and a patient who experienced rapid deterioration have also been reported. Following the death at the University of Toronto of an additional patient who underwent surgery elsewhere, they canvassed pediatric neurosurgeons in North America, Europe, Australia, and Asia for additional cases. Methods. An email was sent to the members of the Canadian Congress of Neurological Sciences who are pediatric neurosurgeons, to the pediatric neurosurgery email list of the American Association of Neurological Surgeons, to the email list of the International Society for Pediatric Neurosurgery, and to designated neurosurgeons in the United Kingdom, France, Japan, Korea, Taiwan, and Australia, who in turn contacted pediatric neurosurgeons in their countries. A data form was provided, and data from previously reported cases were extracted. Nine additional cases were identified, and the results were collated with those of the seven cases previously reported. Patient age at surgery ranged from 2 days to 13 years (mean 7.6 years). The most common causes of hydrocephalus were aqueductal stenosis in 50% of patients and tectal glioma in 25% of patients. The time to treatment failure ranged from 5 weeks to 7.8 years (mean 2.5 years). Thirteen patients died, one patient was in a vegetative state, one patient was mildly disabled, and one patient whose condition deteriorated outside the operating room was alive and well. In the 13 patients in whom the ventriculostomy site was visualized at autopsy or repeated endoscopy, the ventriculostomy was shown to be occluded. Conclusions. Late rapid deterioration is a rare but lethal complication of ETV. The mechanism is unclear, but deterioration can occur long after the ETV becomes occluded. Patients and caregivers should be counseled regarding this potential complication. An indwelling ventricular access device is an option for patients undergoing ETV

Determining the best cerebrospinal fluid shunt valve design: the pediatric valve design trial

Journal ArticleMyriad cerebrospinal fluid shunt valve designs are available (17, IS). None has ever been shown to be superior to another, although claims by neurosurgeons and shunt manufacturers of the merits of particular designs are numerous. Such is the case with two recent shunt valve designs, the Orbis-Sigma valve (Cordis Corporation, Miami, FL) and the Delta valve (PS Medical, Gofetta, CA). Both reduce the siphoning effect when the patient is in the upright position by different mechanisms. Reports of reduced complication rates in uncontrolled series have been attributed to diminished shunt overdrainage (13, 19, 20, 22)

Lack of benefit of endoscopic ventriculoperitoneal shunt insertion: a multicenter randomized trial

Journal ArticleObject. Endoscopically assisted ventricular catheter placement has been reported to reduce shunt failure in uncontrolled series. The authors investigated the efficacy of this procedure in a prospective multicenter randomized trial. Methods. Children younger than 18 years old who were scheduled for their first ventriculoperitoneal (VP) shunt placement were randomized to undergo endoscopic or nonendoscopic insertion of a ventricular catheter. Eligibility and primary outcome (shunt failure) were decided in a blinded fashion. An intention-to-treat analysis was performed. The sample size offered 80% power to detect a 10 to 15% absolute reduction in the 1-year shunt failure rate. The authors studied 393 patients from 16 pediatric neurosurgery centers between May 1996 and November 1999. Median patient age at shunt insertion was 89 days. The baseline characteristics of patients within each group were similar: 54% of patients treated with endoscopy were male and 55% of patients treated without endoscopy were male; 30% of patients treated with and 26% of those without endoscopy had myelomeningocele; a differential pressure valve was used in 51% of patients with and 49% of those treated without endoscopy; a Delta valve was inserted in 38% of patients in each group; and a Sigma valve was placed in 9% of patients treated with and 12% of those treated without endoscopy. Median surgical time lasted 40 minutes in the group treated with and 35 minutes in the group treated without endoscopy. Ventricular catheters, which during surgery were thought to be situated away from the choroid plexus, were demonstrated to be in it on postoperative imaging in 67% of patients who had undergone endoscopic insertion and 61% of those who had undergone nonendoscopic shunt placements. The incidence of shunt failure at 1 year was 42% in the endoscopic insertion group and 34% in the nonendoscopic group. The time to first shunt failure was not different between the two groups (log rank = 2.92, p = 0.09). Conclusions. Endoscopic insertion of the initial VP shunt in children suffering from hydrocephalus did not reduce the incidence of shunt failure

Randomized trial of cerebrospinal fluid shunt valve design in pediatric hydrocephalus

Journal ArticleOBJECTIVE: Forty percent of standard cerebrospinal fluid shunts implanted for the treatment of pediatric hydrocephalus fail within the first year. Two new shunt valves designed to limit excess flow, particularly in upright positions, were studied to compare treatment failure rates with those for standard differential-pressure valves. METHODS: Three hundred-forty-four hydrocephalic children (age, birth to 18 yr) undergoing their first cerebrospinal fluid shunt insertion were randomized at 12 North American or European pediatric neurosurgical centers. Patients received one of three valves, i.e., a standard differential-pressure valve; a Delta valve (Medtronic PS Medical, Goleta, CA), which contains a siphon-control component designed to reduce siphoning in upright positions; or an Orbis-Sigma valve (Cordis, Miami, FL), with a variable-resistance, flow-limiting component. Patients were monitored for a minimum of 1 year. Endpoints were defined as shunt failure resulting from shunt obstruction, overdrainage, loculations of the cerebral ventricles, or infection. Outcome events were assessed by blinded independent case review. RESULTS: One hundred-fifty patients reached an endpoint; shunt obstruction occurred in 108 (31.4%), overdrainage in 12(3.5%), loculated ventricles in 2(0.6%), and infection in 28 (8.1%). Sixty-one percent were shunt failure-free at 1 year and 47% at 2 years, with a median shunt failure-free duration of 656 days. There was no difference in shunt failure-free duration among the three valves (P = 0.24)

James W. Drake to H. R. Miller (4 June 1862)

Description of the Battle of Seven Pines and a large skirmish the preceding weekend; letter similar to Drake\u27s written the previous day to Susan Miller. Also directs Miller to Richmond.https://egrove.olemiss.edu/ciwar_corresp/1613/thumbnail.jp

The Effect of Florida’s Timeshare Resale Accountability Act and Securitization Announcements on Vacation Ownership Shareholder Wealth

The focus of this study deals with the vacation ownership, or timeshare, industry, and is two-fold. First, it examines the passage of a criminal law in Florida that deals with the resale of timeshare properties and measures the law’s effects on the timeshare industry in terms of shareholder wealth. Second, the study examines the effect of the announcement of the sale of asset-backed securities in the timeshare industry, also in terms of shareholder wealth. The cumulative abnormal returns of publicly traded lodging corporations that operate in the timeshare industry are calculated and analyzed for both studies. The passage of Florida’s Timeshare Resale Accountability Act had a somewhat of a significant, positive effect on the shareholder wealth of lodging firms, specifically centering around the date the law became enforceable, which was July 1, 2012, while other key dates in the legislative process had mixed results. The impact of mortgage-backed securitization announcements of lodging firms that have timeshare operations had significant, positive effects on the shareholder wealth of these firms as well. While similar event studies have been performed in the lodging sector, there is a paucity of event study research in the vacation ownership industry. This research focuses on the impact of changes in the state of Florida that effect the timeshare resale market and also the impact that the securitization of mortgage-backed securities has on the shareholder wealth of lodging firms that have timeshare operations

Simulation of fluid flows during growth of organic crystals in microgravity

Several counter diffusion type crystal growth experiments were conducted in space. Improvements in crystal size and quality are attributed to reduced natural convection in the microgravity environment. One series of experiments called DMOS (Diffusive Mixing of Organic Solutions) was designed and conducted by researchers at the 3M Corporation and flown by NASA on the space shuttle. Since only limited information about the mixing process is available from the space experiments, a series of ground based experiments was conducted to further investigate the fluid dynamics within the DMOS crystal growth cell. Solutions with density differences in the range of 10 to the -7 to 10 to the -4 power g/cc were used to simulate microgravity conditions. The small density differences were obtained by mixing D2O and H2O. Methylene blue dye was used to enhance flow visualization. The extent of mixing was measured photometrically using the 662 nm absorbance peak of the dye. Results indicate that extensive mixing by natural convection can occur even under microgravity conditions. This is qualitatively consistent with results of a simple scaling analysis. Quantitave results are in close agreement with ongoing computational modeling analysis

Analog processing of signals from a CZT strip detector with orthogonal coplanar anodes

We present the requirements, design, and performance of an analog circuit for processing the non-collecting anode strip signals from a cadmium zinc telluride (CZT) strip detector with orthogonal coplanar anodes. Detector signal simulations and measurements with a prototype are used to define the range of signal characteristics as a function of location of the gamma interaction in the detector. The signals from the non- collecting anode strip electrodes are used to define two of the three spatial coordinates including the depth of interaction, the z dimension. Analog signal processing options are discussed. A circuit to process the signals from the non- collecting anode strips and extract from them the depth of interaction is described. The circuit employs a time-over- threshold (TOT) measurement. The performance of the detector prototype with a preliminary version of this circuit is presented, and future development work is outlined

Social and clinical predictors of prostate cancer treatment decisions among men in South Carolina

OBJECTIVE: To assess social and clinical influences of prostate cancer treatment decisions among white and black men in the Midlands of South Carolina. METHODS: We linked data collected on treatment decision making in men diagnosed with prostate cancer from 1996 through 2002 with clinical and sociodemographic factors collected routinely by the South Carolina Central Cancer Registry (SCCCR). Unconditional logistic regression was used to assess social and clinical influences on treatment decision. RESULTS: A total of 435 men were evaluated. Men of both races who chose surgery (versus radiation) were more likely to be influenced by their physician and by family/friends. Black men who chose surgery also were ~5 times more likely to make independent decisions (i.e., rather than be influenced by their doctor). White men who chose surgery were twice as likely to be influenced by the desire for cure and less likely to consider the side effects of impotence (odds ratio (OR) = 0.40; 95% confidence interval (CI): 0.18, 0.88) and incontinence (OR = 0.27; 95% CI: 0.12, 0.63); by contrast, there was a suggestion of an opposite effect in black men, whose decision regarding surgery tended to be more strongly influenced by these side effects. CONCLUSION: Results suggest that both clinical and social predictors play an important role for men in choosing a prostate cancer treatment, but these influences may differ by race