Clinical Characteristics and Treatment Outcomes of Spinal Arteriovenous Malformations.

PURPOSE: Spinal arteriovenous malformations (SAVMs) are rare events. This study evaluated initial clinical presentations and treatment outcomes of SAVMs. METHODS: In this study, 91 consecutive patients with SAVM between January 1993 and November 2014 were evaluated. Initial clinical presentations, radiological findings, treatment results, and follow-up outcomes were evaluated according to disease type and treatment modalities. Patient status was scored using the modified Rankin scale (mRS) and Aminoff-Logue Disability scale (ALS). RESULTS: Of the SAVM patients 69 % were male and 31 % were female with a mean age of 49 years (range 11-82 years). At the time of initial imaging evaluation, myelopathy was the most common finding with main complaints of gait disturbance (69 out of 91, 76 %), sensory disturbances (61/91, 67 %), and bowel or bladder symptoms (51/91, 56 %). Among the 80 patients who received treatment 56 (62 %) underwent endovascular embolization and 24 (26 %) underwent surgery. Complete obliteration was achieved in 47 patients (84 %) after endovascular embolization and in 18 (75 %) after surgical ligation. At the time of final follow-up 67 patients (84 %) showed improvement of more than 1 point on the mRS, while 69 (86 %) showed significant improvement on the ALS after treatment. CONCLUSION: The SAVMs presented with diverse neurological deficits, including myelopathy. Endovascular or surgical treatment of SAVMs can result in good clinical outcomes in most patients.

Does a Low-wall Coverage Stent Have a Flow Diverting Effect in Small Aneurysms?

BACKBROUND AND PURPOSE: The flow diverting effect of a low-wall coverage stent remains controversial. We evaluted patients who underwent stenting for small aneurysms with a low but potential risk of growth and reviewed related literature. MATERIALS AND METHODS: We evaluated 9 small aneurysms among 19 unruptured intracranial aneurysms from eight patients who underwent stenting. The patients had unexplainable severe headache (n = 8), aneurysm originating from the anterior choroidal artery (n = 3), potential growth or rupture risks including hypertension (n = 5), and multiple aneurysms (n = 6). Stents with a relatively low-wall coverage ratio (8-10%) were used. Clinical and angiographic outcomes were assessed. RESULTS: One (n = 8) or two stents (n = 1) were used without any procedural difficulties or complications. Although no immediate changes of aneurysm morphology were observed, aneurysms decreased in size (n = 8) when examined by DSA (n = 8) or MRA (n = 1) during a median 28.9-month follow-up. There were no adverse events, including thromboembolism, aneurysm rupture, or stent movement during a median 31.9-month clinical follow-up (range: 17-69 months). CONCLUSION: Although a variable degree of aneurysm size decrease may not prevent further growth or rupture of small aneurysms, stenting with a low-wall coverage ratio may have some advantageous hemodynamic effect. Flow modification of stent architecture vs. aneurysm characteristics, including size and location, on long-term outcome, requires further clarification.

Anesthetic consideration for neurointerventional procedures.

Interventional neuroradiology (INR) has been a rapidly expanding and advancing clinical area during the past few decades. As the complexity and diversity of INR procedures increases, the demand for anesthesia also increases. Anesthesia for interventional neuroradiology is a challenge for the anesthesiologist due to the unfamiliar working environment which the anesthesiologist must consider, as well as the unique neuro-interventional components. This review provides an overview of the anesthetic options and specific consideration of the anesthesia requirements for each procedure. We also introduce the anesthetic management for interventional neuroradiology performed in our medical institution.

A Study Design to Evaluate Association between Smoking and Intracranial Atherosclerotic Stenosis.

PURPOSE: Smoking is a well known risk factor for stroke. The cerebral arteries may be uniquely susceptible to the atherosclerotic effects of smoking, such that it has a different risk profile for stroke compared with other atherosclerosis risk factors. It remains uncertain whether smoking is associated specifically with intracranial (IC) or extracranial (EC) atherosclerotic cerebrovascular disease. The aim of this study design will be to evaluate the association between smoking and severe IC stenosis, adjusting for other atherosclerosis risk factors, particularly age distribution. STUDY DESIGN: This is a retrospective cohort study design. Participants are patients (n=1714) with severe atherosclerotic stenosis undergoing cerebral catheter angiography because of stroke or transient ischaemic attack. All atherosclerotic steno-occlusive lesions are described in terms of location (anterior versus posterior circulation, IC versus EC, or intradural versus extradural). The atherosclerotic or stroke risk factors for analysis include age, gender, smoking history, number of lesions (single versus multiple), cardiac disease, diabetes mellitus, hypertension, family history, dyslipidemia, history of previous stroke, alcohol intake, metabolic syndrome and body mass index. Statistical analysis includes univariate analysis followed by multivariate logistic regression. The relationship between IC atherosclerotic stenosis and smoking will be assessed. Differences in risk factor distribution is analysed according to age at intervals of 10 years. Significant risk factors associated with IC atherosclerotic stenosis will also be assessed by multivariate logistic regression analysis. SUMMARY: This is an analytical study design that intends to measure the association between IC or EC atherosclerotic stenosis and smoking and other risk factors. We anticipate that it will have the power to detect any relationship between smoking and IC atherosclerotic lesions especially in younger patients.

Field modulation in Na-incorporated Cu(In,Ga)Se2 (CIGS) polycrystalline films influenced by alloy-hardening and pair-annihilation probabilities.

The influence of Na on Cu(In,Ga)Se2 (CIGS) solar cells was investigated. A gradient profile of the Na in the CIGS absorber layer can induce an electric field modulation and significantly strengthen the back surface field effect. This field modulation originates from a grain growth model introduced by a combination of alloy-hardening and pair-annihilation probabilities, wherein the Cu supply and Na diffusion together screen the driving force of the grain boundary motion (GBM) by alloy hardening, which indicates a specific GBM pinning by Cu and Na. The pair annihilation between the ubiquitously evolving GBMs has a coincident probability with the alloy-hardening event.PACS: 88. 40. H-, 81. 10. Aj, 81. 40. Cd.

Toxicometabolomics approach to urinary biomarkers for mercuric chloride (HgCl2)-induced nephrotoxicity using proton nuclear magnetic resonance (¹H NMR) in rats.

The primary objective of this study was to determine and characterize surrogate biomarkers that can predict nephrotoxicity induced by mercuric chloride (HgCl2) using urinary proton nuclear magnetic resonance (¹H NMR) spectral data. A procedure for (1)H NMR urinalysis using pattern recognition was proposed to evaluate nephrotoxicity induced by HgCl2 in Sprague-Dawley rats. HgCl2 at 0.1 or 0.75 mg/kg was administered intraperitoneally (i.p.), and urine was collected every 24 h for 6 days. Animals (n=6 per group) were sacrificed 3 or 6 days post-dosing in order to perform clinical blood chemistry tests and histopathologic examinations. Urinary ¹H NMR spectroscopy revealed apparent differential clustering between the control and HgCl2 treatment groups as evidenced by principal component analysis (PCA) and partial least square (PLS)-discriminant analysis (DA). Time- and dose-dependent separation of HgCl2-treated animals from controls was observed by PCA of ¹H NMR spectral data. In HgCl2-treated rats, the concentrations of endogenous urinary metabolites of glucose, acetate, alanine, lactate, succinate, and ethanol were significantly increased, whereas the concentrations of 2-oxoglutarate, allantoin, citrate, formate, taurine, and hippurate were significantly decreased. These endogenous metabolites were selected as putative biomarkers for HgCl2-induced nephrotoxicity. A dose response was observed in concentrations of lactate, acetate, succinate, and ethanol, where severe disruption of the concentrations of 2-oxoglutarate, citrate, formate, glucose, and taurine was observed at the higher dose (0.75 mg/kg) of HgCl2. Correlation of urinary (1)H NMR PLS-DA data with renal histopathologic changes suggests that ¹H NMR urinalysis can be used to predict or screen for HgCl2-induced nephrotoxicity.

Metabolomics approach to risk assessment: methoxyclor exposure in rats.

The primary objective of this study was to develop exposure biomarkers that "correlate with the endocrine-disrupting effects induced by methoxyclor (MTC), an organochlorine pesticide, using" urinary (1)H nuclear magnetic resonance (NMR) spectral data. Exposure biomarkers play an important role in risk assessment. MTC is an environmental endocrine disruptor with estrogenic, anti-estrogenic, and anti-androgenic properties. A new approach of proton nuclear magnetic resonance ((1)H NMR) urinalysis using pattern recognition was proposed for exposure biomarkers of MTC in female rats. The endocrine disruptor was expected to induce estrogenic effects in a dose dependent manner which, was confirmed by the uterotrophic assay. MTC [50, 100, or 200 m g/kg/d, orally (p.o.) or subcutaneously (s.c.)] was administered to ovariectomized female Sprague-Dawley (SD) rats for 3 d consecutively and urine was collected every 24 h. The animals were sacrificed 24 h after the last dose. All animals treated orally with MTC showed a significant increase in uterine and vaginal weight at all doses. However, in the s.c. route, only a high dose of 200 mg MTC/kg induced a significant increase in uterine and vaginal weight. (1)H NMR spectroscopy revealed evident separate clustering between pre- and post-treatment groups using global metabolic profiling through principal component analysis (PCA) and partial least square (PLS) discrimination analysis (DA) after different exposure routes. With targeted profiling, the endogenous metabolites of acetate, alanine, benzoate, lactate, and glycine were selected as putative exposure biomarkers for MTC. Data suggest that the proposed putative exposure biomarkers may be useful in a risk assessment of the endocrine-disrupting effects produced by MTC.