William J. Mack, Louis J. Kim, Demetrius K. Lopes and J Mocco
Brian P. Walcott, Jonathan J. Russin, Robin Babadjouni and William J. Mack
This is the case of a man in his 40s who suffered sudden collapse into a deep coma as a result of a ruptured arteriovenous malformation (AVM) feeding artery aneurysm within the lateral ventricle. The ruptured aneurysm was successfully treated with Onyx embolization of the feeding pedicle. The AVM and the feeding artery aneurysm were then removed via a transcallosal approach. This case highlights the utility of interrogating the AVM with microcatheterization of the feeding pedicles in order to define the exact anatomical features necessary for treatment planning. It also reviews the anatomy of the choroidal fissure.
The video can be found here: https://youtu.be/UeqFzhTRU1Q.
Praveen K. Belur, Jason J. Chang, Shuhan He, Benjamin A. Emanuel and William J. Mack
Intracerebral hemorrhage (ICH) is associated with a higher degree of morbidity and mortality than other stroke subtypes. Despite this burden, currently approved treatments have demonstrated limited efficacy. To date, therapeutic strategies have principally targeted hematoma expansion and resultant mass effect. However, secondary mechanisms of brain injury are believed to be critical effectors of cell death and neurological outcome following ICH. This article reviews the pathophysiology of secondary brain injury relevant to ICH, examines pertinent experimental models, and highlights emerging therapeutic strategies. Treatment paradigms discussed include thrombin inhibitors, deferoxamine, minocycline, statins, granulocyte-colony stimulating factors, and therapeutic hypothermia. Despite promising experimental and preliminary human data, further studies are warranted prior to effective clinical translation.
Omar N. Syed, Todd C. Hankinson, William J. Mack, Neil A. Feldstein and Richard C. E. Anderson
Pediatric neurosurgeons frequently care for children with traumatic scalp and skull injury. Foreign objects are often observed on imaging and may influence the clinician's decision-making process. The authors report on 2 cases of poorly visualized hair beads that had become embedded into the skull during blunt trauma. In both cases, skull radiography and CT scanning demonstrated depressed, comminuted fractures with poorly demonstrated spherical radiolucencies in the overlying scalp. The nature of these objects was initially unclear, and they could have represented air that entered the scalp during trauma. In one case, scalp inspection demonstrated no evidence of the bead. In the other case, a second bead was observed at the site of scalp laceration. In both cases, the beads were surgically removed, the fractures were elevated, and the patients recovered uneventfully. Radiolucent fashion accessories, such as hair beads, may be difficult to appreciate on clinical examination and may masquerade as clinically insignificant air following cranial trauma. If they are not removed, these foreign bodies may pose the risk of an infection. Pediatric neurosurgeons should consider hair accessories in the differential diagnosis of foreign bodies that may produce skull fracture following blunt trauma.
Gabriel Zada, Parham Yashar, Aaron Robison, Jesse Winer, Alexander Khalessi, William J. Mack and Steven L. Giannotta
Tumor consistency plays an important and underrecognized role in the surgeon's ability to resect meningiomas, especially with evolving trends toward minimally invasive and keyhole surgical approaches. Aside from descriptors such as “hard” or “soft,” no objective criteria exist for grading, studying, and conveying the consistency of meningiomas.
The authors designed a practical 5-point scale for intraoperative grading of meningiomas based on the surgeon's ability to internally debulk the tumor and on the subsequent resistance to folding of the tumor capsule. Tumor consistency grades and features are as follows: 1) extremely soft tumor, internal debulking with suction only; 2) soft tumor, internal debulking mostly with suction, and remaining fibrous strands resected with easily folded capsule; 3) average consistency, tumor cannot be freely suctioned and requires mechanical debulking, and the capsule then folds with relative ease; 4) firm tumor, high degree of mechanical debulking required, and capsule remains difficult to fold; and 5) extremely firm, calcified tumor, approaches density of bone, and capsule does not fold. Additional grading categories included tumor heterogeneity (with minimum and maximum consistency scores) and a 3-point vascularity score. This grading system was prospectively assessed in 50 consecutive patients undergoing craniotomy for meningioma resection by 2 surgeons in an independent fashion. Grading scores were subjected to a linear weighted kappa analysis for interuser reliability.
Fifty patients (100 scores) were included in the analysis. The mean maximal tumor diameter was 4.3 cm. The distribution of overall tumor consistency scores was as follows: Grade 1, 4%; Grade 2, 9%; Grade 3, 43%; Grade 4, 44%; and Grade 5, 0%. Regions of Grade 5 consistency were reported only focally in 14% of heterogeneous tumors. Tumors were designated as homogeneous in 68% and heterogeneous in 32% of grades. The kappa analysis score for overall tumor consistency grade was 0.87 (SE 0.06, 95% CI 0.76–0.99), with 90% user agreement. Kappa analysis scores for minimum and maximum grades of tumor regions were 0.69 (agreement 72%) and 0.75 (agreement 78%), respectively. The kappa analysis score for tumor vascularity grading was 0.56 (agreement 76%). Overall consistency did not correlate with patient age, tumor location, or tumor size. A higher tumor vascularity grade was associated with a larger tumor diameter (p = 0.045) and with skull base location (p = 0.02).
The proposed grading system provides a reliable, practical, and objective assessment of meningioma consistency and facilitates communication among providers. This system also accounts for heterogeneity in tumor consistency. With the proposed scale, meningioma consistency can be standardized as groundwork for future studies relating to surgical outcomes, predictability of consistency and vascularity using neuroimaging techniques, and effectiveness of various surgical instruments.
Robin M. Babadjouni, Brian P. Walcott, Qinghai Liu, Matthew S. Tenser, Arun P. Amar and William J. Mack
Despite the success of numerous neuroprotective strategies in animal and preclinical stroke models, none have effectively translated to clinical medicine. A multitude of influences are likely responsible. Two such factors are inefficient recanalization strategies for large vessel occlusions and suboptimal delivery methods/platforms for neuroprotective agents. The recent endovascular stroke trials have established a new paradigm for large vessel stroke treatment. The associated advent of advanced mechanical revascularization devices and new stroke technologies help address each of these existing gaps. A strategy combining effective endovascular revascularization with administration of neuroprotective therapies is now practical and could have additive, if not synergistic, effects. This review outlines past and current neuroprotective strategies assessed in acute stroke trials. The discussion focuses on delivery platforms and their potential applicability to endovascular stoke treatment.
Shuhan He, Martin H. Pham, Matthew Pease, Gabriel Zada, Steven L. Giannotta, Kai Wang and William J. Mack
A more comprehensive understanding of the epigenetic abnormalities associated with meningioma tumorigenesis, growth, and invasion may provide useful targets for molecular classification and development of targeted therapies for meningiomas.
The authors performed a review of the current literature to identify the epigenetic modifications associated with the formation and/or progression of meningiomas.
Several epigenomic alterations, mainly pertaining to DNA methylation, have been associated with meningiomas. Hypermethylation of TIMP3 inactivates its tumor suppression activity while CDKN2 (p14[ARF]) and TP73 gene hypermethylation and HIST1H1c upregulation interact with the p53 regulation of cell cycle control. Other factors such as HOX, IGF, WNK2, and TGF-β epigenetic modifications allow either upregulation or downregulation of critical pathways for meningioma development, progression, and recurrence.
Genome-wide methylation profiling demonstrated that global hypomethylation correlates with tumor grades and severity. Identification of additional epigenetic changes, such as histone modification and higher-order chromosomal structure, may allow for a more thorough understanding of tumorigenesis and enable future individualized treatment strategies for meningiomas.
Daniel Wilson, Diana L. Jin, Timothy Wen, John D. Carmichael, Steven Cen, William J. Mack and Gabriel Zada
Cushing's disease (CD) is a potentially lethal neuroendocrinopathy that often requires specialized multidisciplinary treatment to achieve optimized outcomes. The authors analyzed data pertaining to patient, hospital, and admission characteristics as they relate to outcomes following transsphenoidal surgery (TSS) in more than 5500 patients treated for CD.
The Nationwide Inpatient Sample (NIS) database was used to identify all patients admitted with CD between 2002 and 2010. A variety of patient demographic data (e.g., age, sex, race, payer status), hospital variables (e.g., bed size, TSS volume, teaching status), and admission subtypes (e.g., elective, emergency) were tested for association with postoperative endocrine and nonendocrine complications, mortality, nonroutine discharge, length of stay, and total hospital charges. All tests were performed using univariate analysis followed by multivariate analysis, with 4 models tested via an additive methodology. Statistical significance was defined as a p value < 0.05 for all analyses.
From 2002 to 2010, 5527 individuals who were admitted for TSS (54 biopsies, 4254 partial resections, and 1271 total resections; 5579 total TSS procedures) were identified as patients with CD. There were 25 deaths following TSS, resulting in a mortality incidence rate of 0.45%. Nonendocrine and endocrine complications were reported in 22.4% and 11.1% of patients, respectively. The most common nonendocrine complications were postoperative neurological complications (6.98%) and mechanical ventilation (1.71%). Diabetes insipidus was reported in 14.79% of patients. In a multivariate analysis, patients with Medicare were at increased risk of nonendocrine complications (relative risk [RR] 2.24, 95% CI 1.15–4.38; p = 0.02). Patients with Medicare had increased risk of higher charges (RR 1.89, 95% CI 1.04–3.45; p = 0.04), as did those with Medicaid (RR 1.93, 95% CI 1.10–3.41; p = 0.02). Additionally, as compared with white patients, Hispanic patients had an increased rate of higher charges (RR 1.86, 95% CI 1.12–3.10; p = 0.02). Patients whose age was less than 40 years had a higher risk of developing diabetes insipidus (RR 1.39, 95% CI 1.0–1.93; p = 0.05). When compared with those in northeast hospitals, patients in western hospitals were more likely to experience nonendocrine complications (RR 1.85, 95% CI 0.99–3.46; p = 0.05) and endocrine complications (RR 1.98, 95% CI 1.28–3.07; p < 0.01). Patients treated in teaching hospitals were at significantly lower risk of incurring higher hospital charges (RR 0.49, 95% CI 0.28–0.85; p = 0.01). Patients with emergency admissions had a risk of higher hospital charges (RR 3.06, 95% CI 1.26–7.46; p = 0.01) and nonendocrine complications (RR 3.18, 95% CI 1.22–8.28; p = 0.02).
This review of NIS data in more than 5500 patients treated surgically for CD pointed to major outcome disparities predicted primarily by payer status, admission type, and hospital region. Identification and targeting of such barriers to quality health care in patients with CD may help optimize patient outcomes on a national level and present an opportunity to improve access of high-risk patient subgroups to specialty centers of excellence.
Daniel A. Donoho, Timothy Wen, Jonathan Liu, Hosniya Zarabi, Eisha Christian, Steven Cen, Gabriel Zada, J. Gordon McComb, Mark D. Krieger, William J. Mack and Frank J. Attenello
Although current pediatric neurosurgery guidelines encourage the treatment of pediatric malignant brain tumors at specialized centers such as pediatric hospitals, there are limited data in support of this recommendation. Previous studies suggest that children treated by higher-volume surgeons and higher-volume hospitals may have better outcomes, but the effect of treatment at dedicated children’s hospitals has not been investigated.
The authors analyzed the Healthcare Cost and Utilization Project Kids’ Inpatient Database (KID) from 2000–2009 and included all patients undergoing a craniotomy for malignant pediatric brain tumors based on ICD-9-CM codes. They investigated the effects of patient demographics, tumor location, admission type, and hospital factors on rates of routine discharge and mortality.
From 2000 through 2009, 83.6% of patients had routine discharges, and the in-hospital mortality rate was 1.3%. In multivariate analysis, compared with children treated at an institution designated as a pediatric hospital by NACHRI (National Association of Children’s Hospitals and Related Institutions), children receiving treatment at a pediatric unit within an adult hospital (OR 0.5, p < 0.01) or a general hospital without a designated pediatric unit (OR 0.4, p < 0.01) were less likely to have routine discharges. Treatment at a large hospital (> 400 beds; OR 1.8, p = 0.02) and treatment at a teaching hospital (OR 1.7, p = 0.02) were independently associated with greater likelihood of routine discharge. However, patients transferred between facilities had a significantly decreased likelihood of routine discharge (OR 0.5, p < 0.01) and an increased likelihood of mortality (OR 5.0, p < 0.01). Procedural volume was not associated with rate of routine discharge or mortality.
These findings may have implications for planning systems of care for pediatric patients with malignant brain tumors. The authors hope to motivate future research into the specific factors that may lead to improved outcomes at designated pediatric hospitals.