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Veronica L. Chiang, Michel Torbey, Daniele Rigamonti and Michael A. Williams

✓ The authors report an unusual case of a patient with low-pressure hydrocephalus and a ventriculopleural shunt, in whom routine respiratory management performed using positive-pressure ventilation caused shunt obstruction and coma. While the patient received positive-pressure ventilation with external cerebrospinal fluid (CSF) drainage at subatmospheric pressure, the ventricles returned to normal size and the coma rapidly reversed. After the authors' recognition of the effect of positive-pressure ventilation on intrapleural pressure and ventriculopleural shunt function, and the subsequent removal of positive-pressure ventilation, CSF flow through the shunt resumed and the patient's coma resolved.

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Ian R. Whittle, David B. Williams, G. Michael Halmagyi and Michael Besser

✓ Computerized tomography revealed a thrombosed giant intracavernous carotid aneurysm in a man who presented with ophthalmoplegia and headache. Angiography confirmed complete aneurysmal thrombosis and also revealed complete occlusion of the ipsilateral internal carotid artery. Aneurysmotomy and thrombectomy produced substantial reduction in mass effect, with symptomatic improvement. The spontaneous thrombosis of giant intracranial aneurysms is discussed.

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Marlin Dustin Richardson, Nicholas O. Palmeri, Sarah A. Williams, Michelle R. Torok, Brent R. O’Neill, Michael H. Handler and Todd C. Hankinson

OBJECT

NSAIDs are effective perioperative analgesics. Many surgeons are reluctant to use NSAIDs perioperatively because of a theoretical increase in the risk for bleeding events. The authors assessed the effect of routine perioperative ketorolac use on intracranial hemorrhage in children undergoing a wide range of neurosurgical procedures.

METHODS

A retrospective single-institution analysis of 1451 neurosurgical cases was performed. Data included demographics, type of surgery, and perioperative ketorolac use. Outcomes included bleeding events requiring return to the operating room, bleeding seen on postoperative imaging, and the development of renal failure or gastrointestinal tract injury.

Variables associated with both the exposure and outcomes (p < 0.20) were evaluated as potential confounders for bleeding on postoperative imaging, and multivariable logistic regression was performed. Bivariable analysis was performed for bleeding events. Odds ratios and 95% CIs were estimated.

RESULTS

Of the 1451 patients, 955 received ketorolac. Multivariate regression analysis demonstrated no significant association between clinically significant bleeding events (OR 0.69; 95% CI 0.15–3.1) or radiographic hemorrhage (OR 0.81; 95% CI 0.43–1.51) and the perioperative administration of ketorolac. Treatment with a medication that creates a known bleeding risk (OR 3.11; 95% CI 1.01–9.57), surgical procedure (OR 2.35; 95% CI 1.11–4.94), and craniotomy/craniectomy (OR 2.43; 95% CI 1.19–4.94) were associated with a significantly elevated risk for radiographically identified hemorrhage.

CONCLUSIONS

Short-term ketorolac therapy does not appear to be associated with a statistically significant increase in the risk of bleeding documented on postoperative imaging in pediatric neurosurgical patients and may be considered as part of a perioperative analgesic regimen. Although no association was found between ketorolac and clinically significant bleeding events, a larger study needs to be conducted to control for confounding factors, because of the rarity of these events.

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Michael A. Williams, Phoebe Sharkey, Doris Van Doren, George Thomas and Daniele Rigamonti

Object

The goal in this study was to determine the percentage of patients with hydrocephalus who were treated with shunt surgery and to assess Medicare expenditures for those with and without shunt surgery.

Methods

Retrospective cost analyses were performed using the Standard Analytic Files of paid claims for beneficiaries enrolled in both Parts A (Inpatient) and B (Outpatient) of the Medicare program for 1997 through 2001. The main outcome measures were 5-year total payments and 5-year payments for separate types of service; for example, acute hospital (inpatient and outpatient), skilled nursing facility, home health, and physician/supplier services.

Results

Of 1441 patients with hydrocephalus, 25.1% underwent shunt surgery during the study period. The effect of a shunt procedure on 5-year Medicare expenditures is a cost difference of $25,477 (p < 0.0001) less per patient, which is equal to a potential −$184.3 million difference in 5-year Medicare expenditures. The following three factors had a negative association with whether shunt surgery was performed: 1) age 80 to 84 years (odds ratio [OR] 0.619, confidence interval [CI] 0.390–0.984); 2) age 85 years or older (OR 0.201, CI 0.110–0.366); and 3) African-American race (OR 0.506, CI 0.295–0.869). The effect of age on the likelihood of shunt surgery persisted after adjusting for the propensity to die score.

Conclusions

Medicare expenditures for patients with hydrocephalus treated with shunt surgery are significantly lower than expenditures for untreated patients. Research to improve the diagnosis and treatment of hydrocephalus has the potential to improve outcomes and reduce health care expenditures further.

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Harvey S. Levin, David H. Williams, Michael Valastro, Howard M. Eisenberg, Marsha J. Crofford and Stanley F. Handel

✓ To investigate evidence for diffuse white matter injury and hemispheric disconnection sequelae after severe closed head injury (CHI), this study evaluates the degree of posttraumatic atrophy of the corpus callosum. Corpus callosal atrophy was quantitatively determined using a digitizer to measure sagittal magnetic resonance images of 32 patients with moderate-to-severe CHI and those of 31 control subjects of similar age. In the CHI patients, measurements were significantly reduced for the areas of the anterior four-fifths, the posterior one-fifth, and the total corpus callosum. Moreover, the minimum width of the callosal body was reduced in the CHI patients as compared to that of control individuals. Indices of corpus callosal atrophy were significantly correlated with the chronicity of injury and the degree of lateral ventricular enlargement. There was no difference in callosal measurements between men and women. Magnetic resonance imaging provides an in vivo determination of corpus callosal atrophy which may reflect the severity of diffuse axonal injury and predict the type and severity of hemispheric disconnection effects.

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Romergryko G. Geocadin, Panayiotis N. Varelas, Daniele Rigamonti and Michael A. Williams

Object

The authors attempted to determine whether continuous intracrnial pressure monitoring via the shunt resevoir identifies ventriculoperitoneal (VP) shunt malfunctions that are not identified by radionuclide shunt patency study or shunt tap in adults with hydrocephalus.

Methods

During a 2-year period, 26 adults underwent 32 in-hospital continuous intracranial pressure (ICP) monitoring evaluations via needle access of a shunt reservoir. Monitoring was performed for 26.8 ± 13.8 hours (mean ± standard deviation). No ICP waveform abnormality was detected in 31% of the evaluations (10 of 32). In contrast, abnormalities were detected in 69% (22 of 32 evaluations), including B waves (nine of 22 evaluations), siphoning (nine of 22 evaluations), and variable ICP (two of 22 evaluations). In 20 (91%) of these 22 evaluations, the ICP abnormality was detected only after continuous ICP monitoring; in the other two evaluations, ICP became abnormal immediately on accessing the shunt reservoir. On the basis of the ICP monitoring results, shunt revision was performed in 66% (21 of 32 evaluations) and medical therapy was administered in 34% (11 of 32 evaluations). Shunt revision led to symptom improvement in 82% (18 of 22 patients) and no change in 18% (four of 22 patients); medical therapy led to improvement in 18% (two of 11 patients), worsening in 18% (two of 11 patients), and no change in 64% (seven of 11 patients; p < 0.05).

Conclusions

Continuous ICP monitoring via the shunt reservoir provides a more accurate assessment of shunt malfunction than transient ICP monitoring with a shunt tap or a radionuclide shunt patency study. It is a safe method for evaluating patients with suspected VP shunt malfunction, provides in vivo assessment of the effect of the shunt system on a patient's ICP, and can lead to more effective shunt revision.

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Michael A. Williams, Tessa van der Willigen, Patience H. White, Cathy C. Cartwright, David L. Wood and Mark G. Hamilton

The health care needs of children with hydrocephalus continue beyond childhood and adolescence; however, pediatric hospitals and pediatric neurosurgeons are often unable to provide them care after they become adults. Each year in the US, an estimated 5000–6000 adolescents and young adults (collectively, youth) with hydrocephalus must move to the adult health care system, a process known as health care transition (HCT), for which many are not prepared. Many discover that they cannot find neurosurgeons to care for them. A significant gap in health care services exists for young adults with hydrocephalus. To address these issues, the Hydrocephalus Association convened a Transition Summit in Seattle, Washington, February 17–18, 2017.

The Hydrocephalus Association surveyed youth and families in focus groups to identify common concerns with HCT that were used to identify topics for the summit. Seven plenary sessions consisted of formal presentations. Four breakout groups identified key priorities and recommended actions regarding HCT models and practices, to prepare and engage patients, educate health care professionals, and address payment issues. The breakout group results were discussed by all participants to generate consensus recommendations.

Barriers to effective HCT included difficulty finding adult neurosurgeons to accept young adults with hydrocephalus into their practices; unfamiliarity of neurologists, primary care providers, and other health care professionals with the principles of care for patients with hydrocephalus; insufficient infrastructure and processes to provide effective HCT for youth, and longitudinal care for adults with hydrocephalus; and inadequate compensation for health care services.

Best practices were identified, including the National Center for Health Care Transition Improvement’s “Six Core Elements of Health Care Transition 2.0”; development of hydrocephalus-specific transition programs or incorporation of hydrocephalus into existing general HCT programs; and development of specialty centers for longitudinal care of adults with hydrocephalus.

The lack of formal HCT and longitudinal care for young adults with hydrocephalus is a significant health care services problem in the US and Canada that professional societies in neurosurgery and neurology must address. Consensus recommendations of the Hydrocephalus Association Transition Summit address 1) actions by hospitals, health systems, and practices to meet local community needs to improve processes and infrastructure for HCT services and longitudinal care; and 2) actions by professional societies in adult and pediatric neurosurgery and neurology to meet national needs to improve processes and infrastructure for HCT services; to improve training in medical and surgical management of hydrocephalus and in HCT and longitudinal care; and to demonstrate the outcomes and effectiveness of HCT and longitudinal care by promoting research funding.

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Marvin Bergsneider, Michael R. Egnor, Miles Johnston, Dory Kranz, Joseph R. Madsen, James P. Mcallister II, Curt Stewart, Marion L. Walker and Michael A. Williams

✓In an effort to identify critical gaps in the prevailing knowledge of hydrocephalus, the authors formulated 10 key questions. 1) How do we define hydrocephalus? 2) How is cerebrosinal fluid (CSF) absorbed normally and what are the causes of CSF malabsorption in hydrocephalus? 3) Why do the ventricles dilate in communicating hydrocephalus? 4) What happens to the structure and function of the brain when it is compressed and stretched by the expanding ventricles? 5) What is the role of cerebrovenous pressure in hydrocephalus? 6) What causes normal-pressure hydrocephalus? 7) What causes low-pressure hydrocephalus? 8) What is the pathophysiology of slit ventricle syndrome? 9) What is the pathophysiological basis for neurological impairment in hydrocephalus, and to what extent is it reversible? 10) How is the brain of a child with hydrocephalus different from that of a young or elderly adult? Rigorous answers to these questions should lead to more effective and reliable treatments for this disorder.

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James P. McAllister II, Michael A. Williams, Marion L. Walker, John R. W. Kestle, Norman R. Relkin, Amy M. Anderson, Paul H. Gross and Samuel R. Browd

Building on previous National Institutes of Health-sponsored symposia on hydrocephalus research, “Opportunities for Hydrocephalus Research: Pathways to Better Outcomes” was held in Seattle, Washington, July 9–11, 2012. Plenary sessions were organized into four major themes, each with two subtopics: Causes of Hydrocephalus (Genetics and Pathophysiological Modifications); Diagnosis of Hydrocephalus (Biomarkers and Neuroimaging); Treatment of Hydrocephalus (Bioengineering Advances and Surgical Treatments); and Outcome in Hydrocephalus (Neuropsychological and Neurological). International experts gave plenary talks, and extensive group discussions were held for each of the major themes.

The conference emphasized patient-centered care and translational research, with the main objective to arrive at a consensus on priorities in hydrocephalus that have the potential to impact patient care in the next 5 years. The current state of hydrocephalus research and treatment was presented, and the following priorities for research were recommended for each theme. 1) Causes of Hydrocephalus—CSF absorption, production, and related drug therapies; pathogenesis of human hydrocephalus; improved animal and in vitro models of hydrocephalus; developmental and macromolecular transport mechanisms; biomechanical changes in hydrocephalus; and age-dependent mechanisms in the development of hydrocephalus. 2) Diagnosis of Hydrocephalus—implementation of a standardized set of protocols and a shared repository of technical information; prospective studies of multimodal techniques including MRI and CSF biomarkers to test potential pharmacological treatments; and quantitative and cost-effective CSF assessment techniques. 3) Treatment of Hydrocephalus—improved bioengineering efforts to reduce proximal catheter and overall shunt failure; external or implantable diagnostics and support for the biological infrastructure research that informs these efforts; and evidence-based surgical standardization with longitudinal metrics to validate or refute implemented practices, procedures, or tests. 4) Outcome in Hydrocephalus—development of specific, reliable batteries with metrics focused on the hydrocephalic patient; measurements of neurocognitive outcome and quality-of-life measures that are adaptable, trackable across the growth spectrum, and applicable cross-culturally; development of comparison metrics against normal aging and sensitive screening tools to diagnose idiopathic normal pressure hydrocephalus against appropriate normative age-based data; better understanding of the incidence and prevalence of hydrocephalus within both pediatric and adult populations; and comparisons of aging patterns in adults with hydrocephalus against normal aging patterns.

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Daniel F. Kelly, David B. Goodale, John Williams, Daniel L. Herr, E. Thomas Chappell, Michael J. Rosner, Jeff Jacobson, Michael L. Levy, Martin A. Croce, Allen H. Maniker, Gerald J. Fulda, James V. Lovett, Olga Mohan and Raj K. Narayan

Object. Sedation regimens for head-injured patients are quite variable. The short-acting sedative—anesthetic agent propofol is being increasingly used in such patients, yet little is known regarding its safety and efficacy. In this multicenter double-blind trial, a titratable infusion of 2% propofol accompanied by low-dose morphine for analgesia was compared with a regimen of morphine sulfate in intubated head-injured patients. In both groups, other standard measures of controlling intracranial pressure (ICP) were also used.

Methods. Forty-two patients from 11 centers were evaluated to assess both the safety and efficacy of propofol: 23 patients in the propofol group (mean time of propofol usage 95 ± 87 hours) and 19 patients in the morphine group (mean time of morphine usage 70 ± 54 hours). There was a higher incidence of poor prognostic indicators in the propofol group than in the morphine group: patient age older than 55 years (30.4% compared with 10.5%, p < 0.05), initial Glasgow Coma Scale scores of 3 to 5 (39.1% compared with 15.8%, p < 0.05), compressed or absent cisterns on initial computerized tomography scanning (78.3% compared with 57.9%, p < 0.05), early hypotension and/or hypoxia (26.1% compared with 10.5%, p = 0.07). During treatment there was a trend toward greater use of vasopressors in the propofol group. However, the mean daily ICP and cerebral perfusion pressure were generally similar between groups and, on therapy Day 3, ICP was lower in the propofol group compared with the morphine group (p < 0.05). Additionally, there was less use of neuromuscular blocking agents, benzodiazepines, pentobarbital, and cerebrospinal fluid drainage in the propofol group (p < 0.05). At 6 months postinjury, a favorable outcome (good recovery or moderate disability) was observed in 52.1% of patients receiving propofol and in 47.4% receiving morphine; the mortality rates were 17.4% and 21.1%, respectively. Patients who received the highest doses of propofol for the longest duration tended to have the best outcomes. There were no significant differences between groups in terms of adverse events.

Conclusions. Despite a higher incidence of poor prognostic indicators in the propofol group, ICP therapy was less intensive, ICP was lower on therapy Day 3, and long-term outcome was similar to that of the morphine group. These results suggest that a propofol-based sedation and an ICP control regimen is a safe, acceptable, and, possibly, desirable alternative to an opiate-based sedation regimen in intubated head-injured patients.