Magnetic resonance imaging characteristics of typical and atypical/anaplastic meningiomas - Case series and literature review.

OBJECTIVE: The histologic grades of meningiomas have a significant impact on the risk of recurrence, prognosis, and the need for adjuvant treatment such as radiation therapy. The purpose of this study is to investigate the magnetic resonance imaging (MRI) characteristics of typical and atypical/anaplastic meningiomas. METHODS: The medical records of 32 consecutive patients who underwent meningioma resections between April 2004 and November 2006 were retrospectively reviewed. Preoperative MR studies were reviewed by board-certified neuroradiologists. Both univariate and multivariate analyses were used to analyze the MR characteristics of the typical and atypical/anaplastic meningiomas. A review of pertinent literature was also conducted. RESULTS: Thirty-two patients were identified during the study period. Histopathologic examination of the surgical specimens revealed 27 (84.4% - Group I) typical meningiomas and 5 (15.6% - Group 2) atypical/anaplastic meningiomas. The chi-square test showed that restricted diffusion was much more likely to be present in Group 2 (p < 0.01), and the choline-to-creatinine (Cho/Cr) ratio was significantly higher in Group 2 (8.8 vs. 5.1, p = 0.01). The multivariate analysis confirmed that the atypical/anaplastic group is much more likely to have restricted diffusion (p = 0.02) and higher Cho/Cr ratios (p = 0.03). CONCLUSION: Meningiomas with restricted diffusion and higher Cho/Cr ratio on MR spectroscopy are more likely to be atypical/anaplastic types. Preoperative MRI utilizing these sequences can provide important information which can be valuable to counsel patients regarding prognosis, risk of recurrence and the need for adjuvant radiation in addition to surgical resection.

PKCδ regulates hepatic triglyceride accumulation and insulin signaling in Lepr(db/db) mice.

PKCδ has been linked to key pathophysiological features of non-alcoholic fatty liver disease (NAFLD). Yet, our knowledge of PKCδ's role in NAFLD development and progression in obese models is limited. PKCδ(-/-)/Lepr(db)(/)(db) mice were generated to evaluate key pathophysiological features of NAFLD in mice. Hepatic histology, oxidative stress, apoptosis, gene expression, insulin signaling, and serum parameters were analyzed in Lepr(db)(/)(db) and PKCδ(-/-)/Lepr(db)(/)(db) mice. The absence of PKCδ did not abrogate the development of obesity in Lepr(db)(/)(db) mice. In contrast, serum triglyceride levels and epididymal white adipose tissue weight normalized to body weight were reduced in PKCδ(-/-)/Lepr(db)(/)(db) mice compared Lepr(db)(/)(db) mice. Analysis of insulin signaling in mice revealed that hepatic Akt and GSK3ß phosphorylation were strongly stimulated by insulin in PKCδ(-/-)/Lepr(db)(/)(db) compared Lepr(db)(/)(db) mice. PKCδ may be involved in the development of obesity-associated NAFLD by regulating hepatic lipid metabolism and insulin signaling.

Y-stent-assisted coil embolization of cerebral aneurysms.

Y-stent-assisted coiling is a technique used by neuroendovascular surgeons to treat complex, wide-necked, bifurcation aneurysms in locations such as basilar tip and middle cerebral artery bifurcation. Several recent studies have demonstrated low complication rate and favorable clinical and angiographic outcomes. The Y-stent technique is illustrated here in detail and the intraoperative nuances are also discussed to minimize potential complications associated with technique. The video can be found here: http://youtu.be/77pEmqx_fyQ .

Endovascular transarterial embolization of cerebral arteriovenous malformation with ethylene-vinyl alcohol copolymer.

Cerebral arteriovenous malformations (AVMs) have an estimated 2-4% annual risk of hemorrhage. Treatment options for AVMs include microsurgical resection, stereotactic radiosurgery, and endovascular embolization. As endovascular technology and techniques continue to advance and mature, endovascular embolization is becoming an increasingly vital component of AVM treatment not only as a presurgical treatment to reduce microsurgical risks, but also as a stand-alone curative method in some cases. This case illustrates the successful and curative transarterial embolization of a right frontal AVM in a 17-year-old boy with ethylene-vinyl alcohol copolymer (Onyx). The video can be found here: http://youtu.be/L4hE1MvCZCY .

"Contrast-less" stent-assisted coiling of an A1 aneurysm.

BACKGROUND: Iodine-based contrast medium used in diagnostic and therapeutic cerebrovascular imaging may cause renal toxicity, especially in patients with underlying renal impairment. Contrast dilution may impede efforts of the neurointerventionalist to treat intracranial vascular pathology. METHODS: A 36-year-old man with renal impairment presented with an unruptured A1 segment anterior cerebral artery aneurysm. Previously obtained magnetic resonance angiography was fused with intraoperative noncontrast computed tomography and live 2-dimensional fluoroscopic images. The aneurysm was successfully treated with stent-assisted coil embolization without the use of contrast. RESULTS: Neurointervention without contrast was feasible, and although the presented case is one example, the imaging fusion techniques used in this case can substantially decrease the exposure to contrast and subsequent risk of renal injury during intracranial procedures. CONCLUSIONS: Further development of and experience with this technique is needed to improve its safety and efficacy.

PKC{delta} is activated in a dietary model of steatohepatitis and regulates endoplasmic reticulum stress and cell death.

Hepatic steatosis can progress to the clinical condition of non-alcoholic steatohepatitis (NASH), which is a precursor of more serious liver diseases. The novel PKC isoforms δ and ε are activated by lipid metabolites and have been implicated in lipid-induced hepatic disease. Using a methionine- and choline-deficient (MCD) dietary model of NASH, we addressed the question of whether hepatic PKCδ and PKCε are activated. With progression from steatosis to steatohepatitis, there was activation and increased PKCδ protein content coincident with hepatic endoplasmic reticulum (ER) stress parameters. To examine whether similar changes could be induced in vitro, McA-RH 7777 (McA) hepatoma cells were used. We observed that McA cells stored triglyceride and released alanine aminotransferase (ALT) when treated with MCD medium in the presence of fatty acids. Further, MCD medium with palmitic acid, but not oleic or linoleic acids, maximally activated PKCδ and stimulated ER stress. In PKCδ knockdown McA cells, MCD/fatty acid medium-induced ALT release and ER stress induction were completely blocked, but triglyceride storage was not. In addition, a reduction in the uptake of propidium iodide and the number of apoptotic nuclei and a significant increase in cell viability and DNA content were observed in PKCδ knockdown McA cells incubated in MCD medium with palmitic acid. Our studies show that PKCδ activation and protein levels are elevated in an animal model of steatohepatitis, which was recapitulated in a cell model, supporting the conclusion that PKCδ plays a role in ALT release, the ER stress signal, and cell death.

Proteomic and targeted qPCR analyses of subsurface microbial communities for presence of methane monooxygenase.

The Test Area North (TAN) site at the Idaho National Laboratory near Idaho Falls, ID, USA, sits over a trichloroethylene (TCE) contaminant plume in the Snake River Plain fractured basalt aquifer. Past observations have provided evidence that TCE at TAN is being transformed by biological natural attenuation that may be primarily due to co-metabolism in aerobic portions of the plume by methanotrophs. TCE co-metabolism by methanotrophs is the result of the broad substrate specificity of microbial methane monooxygenase which permits non-specific oxidation of TCE in addition to the primary substrate, methane. Arrays of experimental approaches have been utilized to understand the biogeochemical processes driving intrinsic TCE co-metabolism at TAN. In this study, aerobic methanotrophs were enumerated by qPCR using primers targeting conserved regions of the genes pmoA and mmoX encoding subunits of the particulate MMO (pMMO) and soluble MMO (sMMO) enzymes, respectively, as well as the gene mxa encoding the downstream enzyme methanol dehydrogenase. Identification of proteins in planktonic and biofilm samples from TAN was determined using reverse phase ultra-performance liquid chromatography (UPLC) coupled with a quadrupole-time-of-flight (QToF) mass spectrometer to separate and sequence peptides from trypsin digests of the protein extracts. Detection of MMO in unenriched water samples from TAN provides direct evidence of intrinsic methane oxidation and TCE co-metabolic potential of the indigenous microbial population. Mass spectrometry is also well suited for distinguishing which form of MMO is expressed in situ either soluble or particulate. Using this method, pMMO proteins were found to be abundant in samples collected from wells within and adjacent to the TCE plume at TAN.

Co-registration of Intravascular Ultrasound With Angiographic Imaging for Carotid Artery Disease.

BACKGROUND: Intravascular ultrasound (IVUS) provides endoluminal views and cross-sectional images of carotid arteries but lacks overview of vascular territory provided by angiography. Co-registration of IVUS with angiographic images may provide the potential to navigate both imaging modalities in a synchronous manner. The objective of this study is to evaluate the feasibility and accuracy of co-registering both imaging modalities in the carotid vasculature of the neck. METHODS: Fourteen patients with 15 cervical carotid artery lesions underwent angiography and subsequent treatment. In each case, an IVUS catheter was advanced to the target lesion and a reference angiography sequence was acquired. This was followed by an electrocardiography-triggered fluoroscopy sequence that was initiated upon IVUS catheter pullback. IVUS data collected during pullback were registered with fluoroscopy and evaluated for error and clinical usability. RESULTS: A total of 32 landmarks were identified that demonstrated reasonable agreement during IVUS-angiography co-registration. There was a mean registration error distance of 3.36 mm (SD 2.82 mm) between targets. The longitudinal extent and severity of the disease through the target segment could be easily evaluated after co-registration. CONCLUSION: Semiautomatic tracking and co-registration of angiography and IVUS is a new technology and has the potential to increase the use of IVUS in carotid disease and to proivde the opportunity to optimize procedural outcomes.

Importance of Driving and Potential Impact of Driving Cessation for Rural and Urban Older Adults.

PURPOSE: Analyses compared older drivers from urban, suburban, and rural areas on perceived importance of continuing to drive and potential impact that driving cessation would have on what they want and need to do. METHODS: The AAA LongROAD Study is a prospective study of driving behaviors, patterns, and outcomes of older adults. A cohort of 2,990 women and men 65-79 years of age was recruited during 2015-2017 from health systems or primary care practices near 5 study sites in different parts of the United States. Participants were classified as living in urban, surburban, or rural areas and were asked to rate the importance of driving and potential impact of driving cessation. Logistic regression models adjusted for sociodemographic and driving-related characteristics. FINDINGS: The percentages of older drivers rating driving as "completely important" were 76.9%, 79.0%, and 83.8% for urban, suburban, and rural drivers, respectively (P = .009). The rural drivers were also most likely to indicate driving cessation would have a high impact on what they want or need to do (P < .001). After adjustment for sociodemographic and driving-related characteristics, there was a 2-fold difference for rural versus urban older drivers in odds that driving cessation would have a high impact on what they need to do (OR = 2.03; 95% CI: 1.60-2.58). CONCLUSIONS: Older drivers from rural areas were more likely to rate driving as highly important and the prospect of driving cessation as very impactful. Strategies to enhance both the ability to drive safely and the accessibility of alternative sources of transportation may be especially important for older rural adults.

Surgical management of spontaneous cerebrospinal fistulas and encephaloceles of the temporal bone.

OBJECTIVES/HYPOTHESIS: To describe the presentation, surgical findings, and outcomes in patients with spontaneous temporal bone cerebrospinal fluid (CSF) fistulas and encephaloceles. STUDY DESIGN: Retrospective chart review. METHODS: A retrospective chart review of patients treated for a spontaneous temporal bone CSF fistula and/or encephalocele over a 10-year period was performed. Data recorded included demographic information, presenting signs and symptoms, radiographic and laboratory studies, surgical approach, materials used for repair, surgical complications, and successful closure of the CSF fistula. RESULTS: Fifty patients were identified. Five patients underwent bilateral procedures, for a total of 55 surgical repairs. Thirty-seven of the patients were female, with a mean age of 57.2 years. Seventy percent of patients were obese, with a mean body mass index of 35.0 kg/m2 . The most common presentation was tympanostomy tube otorrhea (68%). Seven patients (14%) presented with meningitis. The middle fossa craniotomy approach was used in 87.3% of cases. Hydroxyapatite bone cement was used in 82.4% of cases. There were four surgical complications: seizure, mastoid infection, tympanic membrane retraction, and a delayed subdural hematoma. There were five persistent or recurrent CSF fistulas that underwent successful revision surgery. CONCLUSIONS: Spontaneous CSF fistulas are most common in obese females and should be suspected with a chronic middle ear effusion, persistent otorrhea after tympanostomy tube placement, or in patients with a history of meningitis. The middle fossa craniotomy approach with the use of hydroxyapatite bone cement has a high success rate with a low incidence of postoperative complications. LEVEL OF EVIDENCE: 4 Laryngoscope, 128:2170-2177, 2018.

Bilateral Thalamic Edema from Coexisting Choroid Plexus Arteriovenous Malformation and Sinus Thrombosis: Case Report.

Bilateral thalamic dysfunction secondary to venous congestion may result from either venous sinus thrombosis or high flow arteriovenous malformations or a combination of both. We present a case of bilateral thalamic edema resulting from concomitant choroid plexus arteriovenous malformation (AVM) and straight sinus thrombosis and describe our treatment approach. The patient presented with several weeks of progressive confusion and memory deficits. Magnetic resonance imaging and venography (MRI/ MRV) showed bilateral thalamic T2 hyperintensities and straight sinus thrombosis. Subsequent cerebral angiography revealed a choroid plexus AVM within the right lateral ventricle. The patient underwent surgical resection of the AVM resulting in postoperative resolution of bilateral thalamic edema on MRI and improvement of his confusion and memory deficits. This case demonstrates a rare example of reversible bilateral thalamic edema secondary to venous hypertension from both an AVM and sinus occlusion after appropriate treatment of the AVM.

Image-Guided Internal Fixation of an Oblique Sagittal Split Fracture of C1 Lateral Mass with Motion Preservation: A Technical Report.

A sagittal split fracture of the C1 lateral mass is an unstable subtype of C1 fractures and has a high propensity for developing late deformities and pain with nonoperative management. A primary internal fixation of this type of fracture has been recently described with good clinical outcomes and preservation of motion. We present a modified technique of primary internal fixation using an obliquely inserted C1 lag screw with imaging guidance. We successfully treated a 55-year-old woman with a unilateral C1 oblique sagittal split fracture who failed nonoperative management. Technical nuances are discussed with a review of pertinent literature.

Bilateral Thalamic Edema from Coexisting Choroid Plexus Arteriovenous Malformation and Sinus Thrombosis: Case Report.

Bilateral thalamic dysfunction secondary to venous congestion may result from either venous sinus thrombosis or high flow arteriovenous malformations or a combination of both. We present a case of bilateral thalamic edema resulting from concomitant choroid plexus arteriovenous malformation (AVM) and straight sinus thrombosis and describe our treatment approach. The patient presented with several weeks of progressive confusion and memory deficits. Magnetic resonance imaging and venography (MRI/ MRV) showed bilateral thalamic T2 hyperintensities and straight sinus thrombosis. Subsequent cerebral angiography revealed a choroid plexus AVM within the right lateral ventricle. The patient underwent surgical resection of the AVM resulting in postoperative resolution of bilateral thalamic edema on MRI and improvement of his confusion and memory deficits. This case demonstrates a rare example of reversible bilateral thalamic edema secondary to venous hypertension from both an AVM and sinus occlusion after appropriate treatment of the AVM.

Presence of the hyperintense acute reperfusion marker on MRI after mechanical thrombectomy for large vessel occlusion is associated with worse early neurological recovery.

BACKGROUND: Mechanical thrombectomy has become the accepted treatment for large vessel occlusion in acute ischemic stroke. Unfortunately, a large cohort of patients do not achieve functional independence with treatment, even though the results are more robust than with medical management. The hyperintense acute reperfusion marker (HARM) on MRI is an indication of the breakdown of the blood-brain barrier and reperfusion injury. OBJECTIVE: To examine the hypothesis that the presence of HARM on MRI correlates with worse neurological recovery after reperfusion therapy. METHODS: We retrospectively reviewed 35 consecutive patients who between February 24, 2016 and April 23, 2016 underwent MRI to determine the presence of HARM after thrombectomy for anterior circulation large vessel occlusion. Demographic, radiographic imaging, and outcome data were collected. Univariate and binary logistic regression models were performed to assess predictors for improvement of the National Institutes of Health Stroke Scale (NIHSS) score by ≥8 points at 24 hours. RESULTS: The 35 patients studied had an average age of 64±14 years of age with a median NIHSS score of 15 (IQR 9-20). Eighteen patients (51%) were found to have a HARM-positive MRI. In univariate analysis, patients with HARM were older, had lower reperfusion rates and more postprocedural hemorrhages. In binary logistic regression modeling, the absence of HARM was independently associated with a ≥8-point NIHSS score improvement at 24 hours (OR=7.14, 95% CI 1.22 to 41.67). CONCLUSIONS: This preliminary analysis shows that the presence of HARM may be linked to worse neurological recovery 24 hours after thrombectomy. Reperfusion injury may affect the number of patients achieving functional independence after treatment.

Progressive Deconstruction of a Distal Posterior Cerebral Artery Aneurysm Using Competitive Flow Diversion.

Progressive deconstruction is an endovascular technique for aneurysm treatment that utilizes flow diverting stents to promote progressive thrombosis by diverting blood flow away from the aneurysm's parent vessel. While the aneurysm thromboses, collateral blood vessels develop over time to avoid infarction that can often accompany acute parent vessel occlusion. We report a 37-year-old woman with a left distal posterior cerebral artery aneurysm that was successfully treated with this strategy. The concept and rationale of progressive deconstruction are discussed in detail.

Use of flow-diverting stents as salvage treatment following failed stent-assisted embolization of intracranial aneurysms.

Flow-diverting stents, including the Pipeline embolization device (PED) and Silk, have been beneficial in the treatment of aneurysms previously unable to be approached via endovascular techniques. Recurrent aneurysms for which stent-assisted embolization has failed are a therapeutic challenge, given the existing intraluminal construct with continued blood flow into the aneurysm. We report our experience using flow-diverting stents in the repair of 25 aneurysms for which stent-assisted embolization had failed. Nineteen (76%) of these aneurysms at the 12-month follow-up showed improved Raymond class occlusion, with 38% being completely occluded, and all aneurysms demonstrated decreased filling. One patient developed a moderate permanent neurologic deficit. Appropriate stent sizing, proximal and distal construct coverage, and preventing flow diverter deployment between the previously deployed stent struts are important considerations to ensure wall apposition and prevention of endoleak. Flow diverters are shown to be a reasonable option for treating previously stented recurrent cerebral aneurysms.

Severe hemiparesis as a prehospital tool to triage stroke severity: a pilot study to assess diagnostic accuracy and treatment times.

INTRODUCTION: With the publication of the recent trials showing the tremendous benefits of mechanical thrombectomy, opportunities exist to refine prehospital processes to identify patients with larger stroke syndromes. MATERIALS AND METHODS: We retrospectively reviewed consecutive patients who were brought via scene flight from rural parts of the region to our institution, from December 1, 2014 to June 5, 2015, with severe hemiparesis or hemiplegia. We assessed the accuracy of the diagnosis of stroke and the number of patients requiring endovascular therapy. Moreover, we reviewed the times along the pathway of patients who were treated with endovascular therapy. RESULTS: 45 patients were brought via helicopter from the field to our institution. 27 (60%) patients were diagnosed with an ischemic stroke. Of these, 12 (26.7%) were treated with mechanical thrombectomy and 6 (13.3%) with intravenous tissue plasminogen activator alone. An additional three patients required embolization procedures for either a dural arteriovenous fistula or cerebral aneurysm. Thus a total of 15 (33%) patients received an endovascular procedure and 21/45 (46.7%) received an acute treatment. For patients treated with thrombectomy, the median time from first medical contact to groin puncture was 101 min, with 8 of the 12 patients (66.7%) being discharged to home. CONCLUSIONS: We have presented a pilot study showing that severe hemiparesis or hemiplegia may be a reasonable prehospital tool in recognizing patients requiring endovascular treatment. Patients being identified earlier may be treated faster and potentially improve outcomes. Further prospective controlled studies are required to assess the impact on outcomes and cost effectiveness using this methodology.

Association of angiotensin converting enzyme gene polymorphism with tachycardia cardiomyopathy.

Despite incessant tachycardia, not all patients develop tachycardia-mediated cardiomyopathy. The cardiac renin-angiotensin system may be involved in cardiac remodelling and fibrosis. The level of angiotension-converting enzyme (ACE) in the serum is associated with a 287 bp insertion (I)/deletion (D) polymorphism in intron 16 of the ACE gene. The DD genotype is associated with increased serum ACE levels and a higher incidence of idiopathic dilated and ischemic cardiomyopathy. The objective of this study was to assess whether the ACE gene I/D polymorphism is responsible for development of tachycardia-mediated cardiomyopathy. We identified 20 consecutive patients with persistent tachycardia and cardiomyopathy who showed significant improvement in ejection fraction after rate control (group A, tachycardia cardiomyopathy group). We compared the I/D genotype frequency of group A with the gene frequency of a separate group of 20 patents who, despite rapid atrial arrhythmias had preserved left ventricular ejection fraction (group B, tachycardia without cardiomyopathy group). These two groups were then compared with 24 healthy normal volunteers (group C). After a mean follow-up of 30 months, group A patients showed improvement in ejection fraction from 20+/-7 to 43+/-9% (p<0.001). Group A had a significantly higher frequency of the DD genotype than groups B and C (p-value <0.035 and <0.009 respectively). The profile of group B patients was intermediate between normal and patients with tachycardia-mediated cardiomyopathy. I/D polymorphism of the ACE gene may account for cardiomyopathy secondary to tachycardia.

Central skull base osteomyelitis: an emerging clinical entity.

OBJECTIVES/HYPOTHESIS: Skull base osteomyelitis (SBO) most commonly results as a complication of otitis externa in diabetic patients. Central or atypical presentations, unrelated to aural pathology, have been documented, though restricted to small patient series or case reports. The current study systematically analyzed the literature to construct the clinical profile of this rare entity. STUDY DESIGN: Systematic review of case series. METHODS: The MEDLINE database was searched for all published cases of central SBO. Four additional cases were included from the University of Texas Southwestern Medical Center. Statistical analysis was performed to identify trends affecting overall outcomes or differences in treatment. RESULTS: A total of 42 cases were included with mean age of 52 years and male:female ratio of 2.2:1. The most common presenting symptoms were headaches and cranial nerve palsies, including VI (31%), IX (29%), and X (29%). Staphylococcus aureus (21%) and Pseudomonas aeruginosa (19%) were the two most common causative pathogens. The mean duration of antimicrobial therapy was 21 weeks, with 55% requiring intravenous antibiotics for a mean duration of 6.9 weeks. Twenty of 42 patients (48%) received surgical biopsy for diagnosis, whereas 18 patients (43%) required adjunct surgical debridement. Women were more likely than men to require multiple courses of therapy (46% vs. 7%, P = .01). The overall mortality was 9.5%, with an additional 31% experiencing residual neurological dysfunction. CONCLUSIONS: Osteomyelitis of the central skull base poses significant challenges for timely and accurate diagnosis. Aggressive management with antimicrobials, coupled with surgical debridement in select cases, may avoid serious neurologic morbidity and mortality.

Manual Aspiration Technique to Retrieve a Prematurely Detached Coil during Cerebral Aneurysm Embolization.

Coil herniation, premature deployment, and fracture are procedure associated complications of endovascular aneurysm embolization that optimally necessitate coil retrieval when feasible. Several published techniques describe different strategies for managing coil complications including various snare retrieval devices, alligator retrieval devices, stent fixation, and open surgical resection of coils when distal blood flow is compromised. We report a novel technique employed to retrieve a prematurely detached coil during an aneurysm embolization using a syringe fixed to the microcatheter to carefully aspirate a loose coil with direct fluoroscopic visualization. This technique can only be utilized in the circumstance where the proximal end of the coil remains in the microcatheter. Conventional techniques of coil retrieval and stenting are discussed and compared to the rational for using the manual aspiration technique.