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Michael J. Albeck, Svend E. Børgesen, Flemming Gjerris, Jes F. Schmidt and Per Soelberg Sørensen

✓ Conductance of cerebrospinal fluid (CSF) outflow (Cout) is an important parameter to be considered in patients with CSF circulation abnormalities. In patients with normal-pressure hydrocephalus it is the single most important parameter in determining if the patient needs CSF shunting. The lower normal limit for Cout has been estimated from the effect of shunting in patients with normal-pressure hydrocephalus, from patients retrospectively reevaluated after recovering from illness, and from patients with known abnormalities in the brain or the CSF system. The true value of Cout in normal individuals, however, has hitherto not been reported.

In the present study, Cout has been measured by a lumbar infusion test in eight young volunteers with no suspicion of disease. The mean intracranial pressure (ICP) was 11 mm Hg and a linear relationship was found between CSF absorption and ICP. The mean Cout was 0.11 ml/min/mm Hg and the lower 95% confidence level was 0.10 ml/min/mm Hg. These values are in accordance with those obtained from previous studies.

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Vijay M. Ravindra, Michael Karsy, Richard H. Schmidt, Philipp Taussky, Min S. Park and Robert J. Bollo

The authors report the case of a previously healthy 6-month-old girl who presented with right arm and leg stiffening consistent with seizure activity. An initial CT scan of the head demonstrated acute subarachnoid hemorrhage in the basal cisterns extending into the left sylvian fissure. Computed tomography angiography demonstrated a 7 × 6 × 5–mm saccular aneurysm of the inferior M2 division of the left middle cerebral artery. The patient underwent left craniotomy and microsurgical clip ligation with wrapping of the aneurysm neck because the vessel appeared circumferentially dysplastic in the region of the aneurysm. Postoperative angiography demonstrated a small remnant, sluggish distal flow, but no significant cerebral vasospasm. Fifty-five days after the initial aneurysm rupture, the patient presented again with an acute intraparenchymal hemorrhage of the left anterior temporal lobe. Angiogram revealed a circumferentially dysplastic superior division of the M2 branch, with a new 5 × 4–mm saccular aneurysm distinct from the first, with 2 smaller aneurysms distal to the new ruptured aneurysm. Endovascular parent vessel occlusion with Onyx was performed. Genetic testing revealed a mutation of the MYH11. To the authors' knowledge, this is the first report of rapid de novo aneurysm formation in an infant with an MYH11 mutation. The authors review the patient's clinical presentation and management and comprehensively review the literature on this topic.

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Ehud Mendel, Joel L. Mayerson, Narendra Nathoo, Rick L. Edgar, Carl Schmidt and Michael J. Miller

Primary pelvic sarcomas remain challenging and complex surgical problems with significant potential for postoperative impairment of ambulation, as well as bowel, bladder, and sexual function. En bloc resection with negative tumor margins represents the best chance of control or cure as current adjuvant therapies remain ineffective. Tumor involvement of the sacrum with extension to the greater sciatic notch and ipsilateral ilium requires an external hemipelvectomy and sagittal sacrectomy with sacrifice of the lower extremity to achieve en bloc resection, followed by lumbar-pelvic reconstruction. A patient with an iliosacral chondrosarcoma is presented to illustrate a novel lumbar-pelvic reconstruction technique, in which vascularized soft tissue and 2 vascularized bone grafts were harvested from the amputated lower extremity and transferred to the pelvis as composite flaps to restore pelvic ring integrity, augment lumbar-pelvic fusion, and close the soft-tissue defect. The biomechanical dynamics of this unique construct are discussed.

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Neha S. Dangayach, Harpreet Singh Grewal, Gian Marco De Marchis, Roberta K. Sefcik, Rachel Bruce, Aarti Chhatlani, E. Sander Connolly, M. Cristina Falo, Sachin Agarwal, Jan Claassen, J. Michael Schmidt and Stephan A. Mayer

OBJECTIVE

Being overweight or mildly obese has been associated with a decreased risk of death or hospitalization in patients with cardiovascular disease. Similarly, overweight patients admitted to an intensive care unit (ICU) have improved survival up to 1 year after admission. These counterintuitive observations are examples of the “obesity paradox.” Does the obesity paradox exist in patients with intracerebral hemorrhage (ICH)? In this study the authors examined whether there was an association between obesity and functional outcome in patients with ICH.

METHODS

The authors analyzed 202 patients admitted to the neurological ICU (NICU) who were prospectively enrolled in the Columbia University ICH Outcomes Project between September 2009 and December 2012. Patients were categorized into 2 groups: overweight (body mass index [BMI] ≥ 25 kg/m2) and not overweight (BMI < 25 kg/m2). The primary outcome was defined as survival with favorable outcome (modified Rankin Scale [mRS] score 0–3) versus death or severe disability (mRS score 4–6) at 3 months.

RESULTS

The mean age of the patients in the study was 61 years. The mean BMI was 28 ± 6 kg/m2. The mean Glasgow Coma Scale score was 10 ± 4 and the mean ICH score was 1.9 ± 1.3. The overall 90-day mortality rate was 41%. Among patients with a BMI < 25 kg/m2, 24% (17/70) had a good outcome, compared with 39% (52/132) among those with a BMI ≥ 25 kg/m2 (p = 0.03). After adjusting for ICH score, sex, do-not-resuscitate code status, and history of hypertension, being overweight or obese (BMI ≥ 25 kg/m2) was associated with twice the odds of having a good outcome compared with patients with BMI < 25 kg/m2 (adjusted odds ratio 2.05, 95% confidence interval 1.03–4.06, p = 0.04).

CONCLUSIONS

In patients with ICH admitted to the NICU, being overweight or obese (BMI ≥ 25 kg/m2) was associated with favorable outcome after adjustment for established predictors. The reason for this finding requires further study.

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Charles L. Francoeur, David Roh, J. Michael Schmidt, Stephan A. Mayer, M. Cristina Falo, Sachin Agarwal, E. Sander Connolly, Jan Claassen, Mitchell S. V. Elkind and Soojin Park

OBJECTIVE

Rebleeding remains a frequent and catastrophic event leading to poor outcome after subarachnoid hemorrhage (SAH). Reduced platelet function after the initial bleed is associated with higher risk of early rebleeding. Desmopressin (DDAVP) is a well-known hemostatic agent, and recent guidelines already suggest its use in individuals exposed to antiplatelet drugs. The authors hypothesized that DDAVP administration in patients with SAH at admission would be associated with lower risks of rebleeding.

METHODS

The authors performed an observational cohort study of patients enrolled in the Columbia University SAH Outcome Project between August 1996 and July 2015. The authors compared the rate of rebleeding between patients who were and those who were not treated with DDAVP. After adjustment for known predictors, logistic regression was used to measure the association between treatment with DDAVP and risks of rebleeding.

RESULTS

Among 1639 patients with SAH, 12% were treated with DDAVP. The main indication for treatment was suspected exposure to an antiplatelet agent. The overall incidence of rebleeding was 9% (1% among patients treated with DDAVP compared with 8% among those not treated). After adjustment for antiplatelet use and known predictors, treatment with DDAVP was associated with a 45% reduction in the risks of rebleeding (adjusted OR 0.55, 95% CI 0.27–0.97). DDAVP was associated with a higher incidence of hyponatremia but not with thrombotic events or delayed cerebral ischemia.

CONCLUSIONS

Treatment with DDAVP was associated with a lower risk of rebleeding among patients with SAH. These findings support further study of DDAVP as first-line therapy for medical hemostasis in patients with SAH.

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Alim P. Mitha, Benjamin Reichardt, Michael Grasruck, Eric Macklin, Soenke Bartling, Christianne Leidecker, Bernhard Schmidt, Thomas Flohr, Thomas J. Brady, Christopher S. Ogilvy and Rajiv Gupta

Object

Imaging of intracranial aneurysms using conventional multidetector CT (MDCT) is limited because of nonvisualization of features such as perforating vessels, pulsatile blebs, and neck remnants after clip placement or coil embolization. In this study, a model of intracranial saccular aneurysms in rabbits was used to assess the ultra-high resolution and dynamic scanning capabilities of a prototype flat-panel volumetric CT (fpVCT) scanner in demonstrating these features.

Methods

Ten New Zealand white rabbits underwent imaging before and after clipping or coil embolization of surgically created aneurysms in the proximal right carotid artery. Imaging was performed using a prototype fpVCT scanner, a 64-slice MDCT scanner, and traditional catheter angiography. In addition to the slice data and 3D views, 4D dynamic views, a capability unique to fpVCT, were also created and reviewed. The images were subjectively compared on 1) 4 image quality metrics (spatial resolution, noise, motion artifacts, and aneurysm surface features); 2) 4 posttreatment features reflecting the metal artifact profile of the various imaging modalities (visualization of clip or coil placement, perianeurysmal clip/coil anatomy, neck remnant, and white-collar sign); and 3) 2 dynamic features (blood flow pattern and aneurysm pulsation).

Results

Flat-panel volumetric CT provided better image resolution than MDCT and was comparable to traditional catheter angiography. The surface features of aneurysms were demonstrated with much higher resolution, detail, and clarity by fpVCT compared with MDCT and angiography. Flat-panel volumetric CT was inferior to both MDCT and angiography in terms of image noise and motion artifacts. In fpVCT images, the metallic artifacts from clips and coils were significantly fewer than those in MDCT images. As a result, clinically important information about posttreatment aneurysm neck remnants could be derived from fpVCT images but not from MDCT images. Time-resolved dynamic sequences were judged slightly inferior to conventional angiography but superior to static MDCT images.

Conclusions

The spatial resolution, surface anatomy visualization, metal artifact profile, and 4D dynamic images from fpVCT are superior to those from MDCT. Flat-panel volumetric CT demonstrates aneurysm surface features to better advantage than angiography and is comparable to angiography in metal artifact profile. Even though the temporal resolution of fpVCT is not quite as good as that of angiography, fpVCT images yield clinically important anatomical information about aneurysm surface features and posttreatment neck remnants not attainable with either angiography or MDCT images.

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Grace H. Kim, Christopher P. Kellner, David K. Hahn, Brianna M. Desantis, Muhith Musabbir, Robert M. Starke, Michal Rynkowski, Ricardo J. Komotar, Marc L. Otten, Robert Sciacca, J. Michael Schmidt, Stephan A. Mayer and E. Sander Connolly Jr.

Object

Despite efforts to elucidate both the molecular mechanism and the clinical predictors of vasospasm after aneurysmal subarachnoid hemorrhage (ASAH), its pathogenesis remains unclear. Monocyte chemoattractant protein–1 (MCP-1) is a chemokine that has been firmly implicated in the pathophysiology of vasospasm and in neural tissue injury following focal ischemia in both animal models and human studies. The authors hypothesized that MCP-1 would be found in increased concentrations in the blood and cerebrospinal fluid (CSF) of patients with ASAH and would correlate with both outcome and the occurrence of vasospasm.

Methods

Seventy-seven patients who presented with ASAH were prospectively enrolled in this study between July 2001 and May 2002. Using an enzyme-linked immunosorbent assay, MCP-1 levels were measured in serum daily and in CSF when available. The mean serum and CSF MCP-1 concentrations were calculated for each patient throughout the entire hospital stay. Neurological outcome was evaluated at discharge or 14 days posthemorrhage using the modified Rankin Scale. Vasospasm was evaluated on angiography.

Results

The serum MCP-1 concentrations correlated with negative outcome such that a 10% increase in concentration predicted a 25% increase in the probability of a poor outcome, whereas the serum MCP-1 levels did not correlate with vasospasm. Concentrations of MCP-1 in the CSF, however, proved to be significantly higher in patients with angiographically demonstrated vasospasm.

Conclusions

These findings suggest a role for MCP-1 in neurological injury and imply that it may act as a biomarker of poor outcome in the serum and of vasospasm in the CSF.

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Mark H. Bilsky, Ilya Laufer, Daryl R. Fourney, Michael Groff, Meic H. Schmidt, Peter Paul Varga, Frank D. Vrionis, Yoshiya Yamada, Peter C. Gerszten and Timothy R. Kuklo

Objective

The evolution of imaging techniques, along with highly effective radiation options has changed the way metastatic epidural tumors are treated. While high-grade epidural spinal cord compression (ESCC) frequently serves as an indication for surgical decompression, no consensus exists in the literature about the precise definition of this term. The advancement of the treatment paradigms in patients with metastatic tumors for the spine requires a clear grading scheme of ESCC. The degree of ESCC often serves as a major determinant in the decision to operate or irradiate. The purpose of this study was to determine the reliability and validity of a 6-point, MR imaging–based grading system for ESCC.

Methods

To determine the reliability of the grading scale, a survey was distributed to 7 spine surgeons who participate in the Spine Oncology Study Group. The MR images of 25 cervical or thoracic spinal tumors were distributed consisting of 1 sagittal image and 3 axial images at the identical level including T1-weighted, T2-weighted, and Gd-enhanced T1-weighted images. The survey was administered 3 times at 2-week intervals. The inter- and intrarater reliability was assessed.

Results

The inter- and intrarater reliability ranged from good to excellent when surgeons were asked to rate the degree of spinal cord compression using T2-weighted axial images. The T2-weighted images were superior indicators of ESCC compared with T1-weighted images with and without Gd.

Conclusions

The ESCC scale provides a valid and reliable instrument that may be used to describe the degree of ESCC based on T2-weighted MR images. This scale accounts for recent advances in the treatment of spinal metastases and may be used to provide an ESCC classification scheme for multicenter clinical trial and outcome studies.

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J. Michael Schmidt, Katja E. Wartenberg, Andres Fernandez, Jan Claassen, Fred Rincon, Noeleen D. Ostapkovich, Neeraj Badjatia, Augusto Parra, E. Sander Connolly and Stephan A. Mayer

Object

The authors sought to determine frequency, risk factors, and impact on outcome of asymptomatic cerebral infarction due to vasospasm after subarachnoid hemorrhage (SAH).

Methods

The authors prospectively studied 580 patients with SAH admitted to their center between July 1996 and May 2002. Delayed cerebral ischemia (DCI) from vasospasm was defined as 1) a new focal neurological deficit or decrease in level of consciousness, 2) a new infarct revealed by follow-up CT imaging, or both, after excluding causes other than vasospasm. Outcome at 3 months was assessed using the modified Rankin Scale.

Results

Delayed cerebral ischemia occurred in 121 (21%) of 580 patients. Of those with DCI, 36% (44 patients) experienced neurological deterioration without a corresponding infarct, 42% (51 patients) developed an infarct in conjunction with neurological deterioration, and 21% (26 patients) had a new infarct on CT without concurrent neurological deterioration. In a multivariate analysis, risk factors for asymptomatic DCI included coma on admission, placement of an external ventricular drain, and smaller volumes of SAH (all p ≤ 0.03). Patients with asymptomatic DCI were less likely to be treated with vasopressor agents than those with symptomatic DCI (64 vs 86%, p = 0.01). After adjusting for clinical grade, age, and aneurysm size, the authors found that there was a higher frequency of death or moderate-to-severe disability at 3 months (modified Rankin Scale Score 4–6) in patients with asymptomatic DCI than in patients with symptomatic DCI (73 vs 40%, adjusted odds ratio 3.9, 95% confidence interval 1.3–12.0, p = 0.017).

Conclusions

Approximately 20% of episodes of DCI after SAH are characterized by cerebral infarction in the absence of clinical symptoms. Asymptomatic DCI is particularly common in comatose patients and is associated with poor outcome. Strategies directed at diagnosing and preventing asymptomatic infarction from vasospasm in patients with poor-grade SAH are needed.

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Nikolaos Mouchtouris, Fadi Al Saiegh, Evan Fitchett, Carrie E. Andrews, Michael J. Lang, Ritam Ghosh, Richard F. Schmidt, Nohra Chalouhi, Guilherme Barros, Hekmat Zarzour, Victor Romo, Nabeel Herial, Pascal Jabbour, Stavropoula I. Tjoumakaris, Robert H. Rosenwasser and M. Reid Gooch

OBJECTIVE

The advent of mechanical thrombectomy (MT) has become an effective option for the treatment of acute ischemic stroke in addition to tissue plasminogen activator (tPA). With recent advances in device technology, MT has significantly altered the hospital course and functional outcomes of stroke patients. The authors’ goal was to establish the most up-to-date reperfusion and functional outcomes with the evolution of MT technology.

METHODS

The authors conducted a retrospective study of 403 patients who underwent MT for ischemic stroke at their institution from 2010 to 2017. They collected data on patient comorbidities, National Institutes of Health Stroke Scale (NIHSS) score on arrival, tPA administration, revascularization outcomes, and functional outcomes on discharge.

RESULTS

In 403 patients, the mean NIHSS score on presentation was 15.8 ± 6.6, with 195 (48.0%) of patients receiving tPA prior to MT. Successful reperfusion (thrombolysis in cerebral infarction score 2B or 3) was achieved in 84.4%. Hemorrhagic conversion with significant mass effect was noted in 9.9% of patients. The median lengths of ICU and hospital stay were 3.0 and 7.0 days, respectively. Functional independence (modified Rankin Scale score 0–2) was noted in 125 (31.0%) patients, while inpatient mortality occurred in 43 (10.7%) patients.

CONCLUSIONS

As MT has established acute ischemic stroke as a neurosurgical disease, there is a pressing need to understand the hospital course, hospital- and procedure-related complications, and outcomes for this new patient population. The authors provide a detailed account of key metrics for MT with the latest device technology and identify the predictors of unfavorable outcomes and inpatient mortality.