✓In an effort to help clarify the current state of medical therapy for cerebral vasospasm, the authors reviewed the relevant literature on the established medical therapies used for cerebral vasospasm following aneurysmal subarachnoid hemorrhage (SAH), and they discuss burgeoning areas of investigation. Despite advances in the treatment of aneurysmal SAH, cerebral vasospasm remains a common complication and has been correlated with a 1.5- to threefold increase in death during the first 2 weeks after hemorrhage. A number of medical, pharmacological, and surgical therapies are currently in use or being investigated in an attempt to reverse cerebral vasospasm, but only a few have proven to be useful. Although much has been elucidated regarding its pathophysiology, the treatment of cerebral vasospasm remains a dilemma. Although a poor understanding of SAH-induced cerebral vasospasm pathophysiology has, to date, hampered the development of therapeutic interventions, current research efforts promise the eventual production of new medical therapies.
J Mocco, Brad E. Zacharia, Ricardo J. Komotar and E. Sander Connolly Jr.
Jason A. Ellis, Hannah Goldstein, E. Sander Connolly Jr. and Philip M. Meyers
Carotid-cavernous fistulas (CCFs) are vascular shunts allowing blood to flow from the carotid artery into the cavernous sinus. The characteristic clinical features seen in patients with CCFs are the sequelae of hemodynamic dysfunction within the cavernous sinus. Once routinely treated with open surgical procedures, including carotid ligation or trapping and cavernous sinus exploration, endovascular therapy is now the treatment modality of choice in many cases. The authors provide a review of CCFs, detailing the current classification and clinical management of these lesions. Therapeutic options including conservative management, open surgery, endovascular intervention, and radiosurgical therapy are presented. The complications and treatment results as reported in the contemporary literature are also reviewed.
Ivan S. Kotchetkov, Brian Y. Hwang, Geoffrey Appelboom, Christopher P. Kellner and E. Sander Connolly Jr.
Brain-computer interfaces (BCIs) are devices that acquire and transform neural signals into actions intended by the user. These devices have been a rapidly developing area of research over the past 2 decades, and the military has made significant contributions to these efforts. Presently, BCIs can provide humans with rudimentary control over computer systems and robotic devices. Continued advances in BCI technology are especially pertinent in the military setting, given the potential for therapeutic applications to restore function after combat injury, and for the evolving use of BCI devices in military operations and performance enhancement. Neurosurgeons will play a central role in the further development and implementation of BCIs, but they will also have to navigate important ethical questions in the translation of this highly promising technology. In the following commentary the authors discuss realistic expectations for BCI use in the military and underscore the intersection of the neurosurgeon's civic and clinical duty to care for those who serve their country.
Ricardo J. Komotar, J Mocco, David A. Wilson, E. Sander Connolly Jr., Sean D. Lavine and Philip M. Meyers
A substantial number of strokes are caused by intracranial atherosclerosis, a disease that traditionally has been treated medically. Recent technological advancements, however, have revolutionized the treatment of this condition by enabling the use of endovascular methods. In this paper the authors focus on the internal carotid artery, and review relevant studies concerning angioplasty with stent placement for the management of intracranial atherosclerosis in this vessel. With continued experience and a multidisciplinary approach in the evaluation of these patients, favorable outcomes may be achieved.
Christian Stapf, Jay P. Mohr, John Pile-Spellman, Robert A. Solomon, Ralph L. Sacco and E. Sander Connolly Jr.
The epidemiology and natural history of cerebral arteriovenous malformations (AVMs) remains incompletely elucidated. Several factors are responsible. With regard to the incidence and prevalence of AVMs, the results of prior studies have suffered because of the retrospective design, the use of nonspecific ICD-9 codes, and a focus on small genetically isolated populations. Recent data from the New York Islands AVM Hemorrhage Study, an ongoing, prospective, population-based survey determining the incidence of AVM-related hemorrhage and the associated rates of morbidity and mortality in a zip code–defined population of 10 million people, suggests that the AVM detection rate is 1.21/100,000 person-years (95% confidence interval [CI] 1.02–1.42) and the incidence of AVM-hemorrhage is 0.42/100,000 person-years (95% CI 0.32–0.55). Contemporaneous data from the Northern Manhattan Stroke Study, a prospective, longitudinal population-based study of nearly 150,000 patients in which the focus is to define the incidence of stroke, suggest the crude incidence for first-ever AVM-related hemorrhage to be 0.55/100,000 person-years (95% CI 0.11–1.61). Efforts are ongoing to study the natural history of both ruptured and unruptured AVMs in these datasets to examine the relevance of prior studies of patients selected for conservative follow up in Finland. In addition, data are being gathered to determine whether risk factors for future hemorrhage, which have previously been established in small case series, are valid when applied to whole populations. Together, these data should help inform therapeutic decisionmaking.
Ricardo J. Komotar, J Mocco, David A. Wilson, E. Sander Connolly Jr., Sean D. Lavine and Philip M. Meyers
Intracranial atherosclerosis is the cause of a significant number of strokes. Despite maximal medical therapy, this disease continues to carry a poor prognosis. The authors reviewed studies in which the outcomes after conservative management in patients with intracranial carotid artery atherosclerosis were reported. Analysis of the literature demonstrates that maximal medical therapy frequently fails with this disease, leaving patients at high risk for cerebral infarction and death. A better understanding of the pathophysiological aspects and natural history of this condition may serve to guide clinical decision making and the choice of therapeutic options in this patient population.
William J. Mack, Ryan G. King, Andrew F. Ducruet, Kurt Kreiter, J Mocco, Ahmed Maghoub, Stephan Mayer and E. Sander Connolly Jr.
Elevated intracranial pressure (ICP) is an important consequence of aneurysmal subarachnoid hemorrhage (SAH) that often results in decreased cerebral perfusion and secondary clinical decline. No definitive guidelines exist regarding methods and techniques for ICP management following aneurysm rupture. The authors describe monitoring practices and outcome data in 621 patients with aneurysmal SAH admitted to their neurological intensive care unit during an 8-year period (1996–2003).
A fiberoptic catheter tip probe or external ventricular drain (EVD) was used to record ICP values. The percentage of monitored patients varied, as expected, according to admission Hunt and Hess grade (p < 0.0001). Intracranial pressure monitoring devices were used in 27 (10%) of 264 Grade I to II patients, 72 (38%) of 189 Grade III patients, and 134 (80%) of 168 Grade IV to V patients. There was a strong propensity to favor transduced ventricular drains over parenchymal fiberoptic bolts, with the former used in 221 (95%) of 233 cases. This tendency was particularly strong in the poor-grade cohort, in which EVDs were placed in 99% of monitored individuals. The rates of cerebrospinal fluid infection in patients in whom ICP probes (0%) and ventricular drains (12%) were placed accorded with those in the literature.
Following aneurysmal SAH, ICP monitoring prevalence and techniques differ with respect to admission Hunt and Hess grade and are associated with the patient's functional status at discharge.
Brad E. Zacharia, Kerry A. Vaughan, Zachary L. Hickman, Samuel S. Bruce, Amanda M. Carpenter, Nils H. Petersen, Stacie Deiner, Neeraj Badjatia and E. Sander Connolly Jr
Intracerebral hemorrhage (ICH) is frequently complicated by acute hydrocephalus, necessitating emergency CSF diversion with a subset of patients, ultimately requiring long-term treatment via placement of permanent ventricular shunts. It is unclear what factors may predict the need for ventricular shunt placement in this patient population.
The authors performed a retrospective analysis of a prospective database (ICH Outcomes Project) containing patients with nontraumatic ICH admitted to the neurological ICU at Columbia University Medical Center between January 2009 and September 2011. A multiple logistic regression model was developed to identify independent predictors of shunt-dependent hydrocephalus after ICH. The following variables were included: patient age, admission Glasgow Coma Scale score, temporal horn diameter on admission CT imaging, bicaudate index, admission ICH volume and location, intraventricular hemorrhage volume, Graeb score, LeRoux score, third or fourth ventricle hemorrhage, and intracranial pressure (ICP) and ventriculitis during hospital stay.
Of 210 patients prospectively enrolled in the ICH Outcomes Project, 64 required emergency CSF diversion via placement of an external ventricular drain and were included in the final cohort. Thirteen of these patients underwent permanent ventricular CSF shunting prior to discharge. In univariate analysis, only thalamic hemorrhage and elevated ICP were significantly associated with the requirement for permanent CSF diversion, with p values of 0.008 and 0.033, respectively. Each remained significant in a multiple logistic regression model in which both variables were present.
Of patients with ICH requiring emergency CSF diversion, those with persistently elevated ICP and thalamic location of their hemorrhage are at increased odds of developing persistent hydrocephalus, necessitating permanent ventricular shunt placement. These factors may assist in predicting which patients will require permanent CSF diversion and could ultimately lead to improvements in the management of this disorder and the outcome in patients with ICH.
Simon G. Heuts, Samuel S. Bruce, Brad E. Zacharia, Zachary L. Hickman, Christopher P. Kellner, Eric S. Sussman, Michael M. McDowell, Rachel A. Bruce and E. Sander Connolly Jr.
Large intracerebral hemorrhage (ICH), compounded by perihematomal edema, can produce severe elevations of intracranial pressure (ICP). Decompressive hemicraniectomy (DHC) with or without clot evacuation has been considered a part of the armamentarium of treatment options for these patients. The authors sought to assess the preliminary utility of DHC without evacuation for ICH in patients with supratentorial, dominant-sided lesions.
From September 2009 to May 2012, patients with ICH who were admitted to the neurological ICU at Columbia University Medical Center were prospectively enrolled in that institution's ICH Outcomes Project (ICHOP). Five patients with spontaneous supratentorial dominant-sided ICH underwent DHC without clot evacuation for recalcitrant elevated ICP. Data pertaining to the patients' characteristics and outcomes of treatment were prospectively collected.
The patients' median age was 43 years (range 30–55 years) and the ICH etiology was hypertension in 4 of 5 patients, and systemic lupus erythematosus vasculitis in 1 patient. On admission, the median Glasgow Coma Scale (GCS) score was 7 (range 5–9). The median ICH volume was 53 cm3 (range 28–79 cm3), and the median midline shift was 7.6 mm (range 3.0–11.3 mm). One day after surgery, the median decrease in midline shift was 2.7 mm (range 1.5–4.6 mm), and the median change in GCS score was +1 (range −3 to +5). At discharge, all patients were still alive, and the median GCS score was 10 (range 9–11), the median modified Rankin Scale (mRS) score was 5 (range 5–5), and the median NIHSS (National Institutes of Health Stroke Scale) score was 22 (range 17–27). Six months after hemorrhage, 1 patient had died, 2 were functionally dependent (mRS Score 4–5), and 2 were functionally independent (mRS Score 0–3). Outcomes for the patients treated with DHC were good compared with 1) outcomes for all patients with spontaneous supratentorial ICH admitted during the same period (n = 144) and 2) outcomes for matched patients (dominant ICH, GCS Score 5–9, ICH volume 28–79 cm3, age < 60 years) whose cases were managed nonoperatively (n = 5).
Decompressive hemicraniectomy without clot evacuation appears feasible in patients with large ICH and deserves further investigation, preferably in a randomized controlled setting.
Eric S. Sussman, Christopher P. Kellner, Michael M. McDowell, Samuel S. Bruce, Simon G. Heuts, Zong Zhuang, Rachel A. Bruce, Jan Claassen and E. Sander Connolly Jr.
Intracerebral hemorrhage (ICH) is the most deadly and least treatable subtype of stroke, and at the present time there are no evidence-based therapeutic interventions for patients with this disease. Secondary injury mechanisms are known to cause substantial rates of morbidity and mortality following ICH, and the inflammatory cascade is a major contributor to this post-ICH secondary injury. The alpha-7 nicotinic acetylcholine receptor (α7-nAChR) agonists have a well-established antiinflammatory effect and have been shown to attenuate perihematomal edema volume and to improve functional outcome in experimental ICH. The authors evaluate the current evidence for the use of an α7-nAChR agonist as a novel therapeutic agent in patients with ICH.