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BACKGROUND AND PURPOSE:Embolization of the middle meningeal artery for treatment of refractory or recurrent chronic subdural hematomas has gained momentum during the past few years. Little has been reported on the use of the n-BCA liquid embolic system for middle meningeal artery embolization. We present the technical feasibility of using diluted n-BCA for middle meningeal artery embolization.MATERIALS AND METHODS:We sought to examine the safety and technical feasibility of the diluted n-BCA liquid embolic system for middle meningeal artery embolization. Patients with chronic refractory or recurrent subdural hematomas were prospectively enrolled from September 2019 to June 2020. The primary outcome was the safety and technical feasibility of the use of diluted n-BCA for embolization of the middle meningeal artery. The secondary end point was the efficacy in reducing hematoma volume.RESULTS:A total of 16 patients were prospectively enrolled. Concomitant burr-hole craniotomies were performed in 12 of the 16 patients. Two patients required an operation following middle meningeal artery embolization for persistent symptoms. The primary end point was met in 100% of cases in which there were no intra- or postprocedural complications. Distal penetration of the middle meningeal artery branches was achieved in all the enrolled cases. A 7-day post–middle meningeal artery embolization follow-up head CT demonstrated improvement (>50% reduction in subdural hematoma volume) in 9/15 (60%) patients, with 6/15 (40%) showing an unchanged or stable subdural hematoma. At day 21, available CT scans demonstrated substantial further improvement (>75% reduction in subdural hematoma volume).CONCLUSIONS:Embolization of the middle meningeal artery using diluted n-BCA and ethiodized oil (1:6) is safe and feasible from a technical standpoint. The use of a dextrose 5% bolus improves distal penetration of the glue.

Despite traditional treatment with surgical evacuation, chronic subdural hematomas (cSDHs) tend to have an indolent course with frequent recurrences.1 In recent years, embolization of the middle meningeal artery (MMA) for treatment of refractory or recurrent cSDH has gained momentum, with recent literature showing a significant reduction in the size of the cSDH as well as lower rates of recurrence.2 The primary endovascular techniques used to date have involved the use of polyvinyl alcohol particles (PVA) and Onyx liquid embolic (ethylene-vinyl alcohol dissolved in dimethyl-sulfoxide; Medtronic). Another commonly used liquid embolic agent in the neurointerventional area is n-BCA, which is a liquid adhesive that polymerizes rapidly on contact with ionic substances and can be injected to achieve permanent vessel occlusion. The rates of polymerization and flow and the penetration depth can be modified using varying amounts of ethiodized oil as well as concurrent infusion of dextrose 5% in water (D5W) during n-BCA (Trufill, Cordis Neurovascular) injection (D5W-push technique).3 Data on the use of n-BCA as an embolic agent in cases of cSDH are extremely limited. Herein, we sought to study the safety and technical feasibility of using diluted n-BCA for embolization of the MMA for cSDHs.  相似文献   
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Fast CT-PRESS-based spiral chemical shift imaging at 3 Tesla.   总被引:2,自引:0,他引:2  
A new sequence is presented that combines constant-time point-resolved spectroscopy (CT-PRESS) with fast spiral chemical shift imaging. It allows the acquisition of multivoxel spectra without line splitting with a minimum total measurement time of less than 5 min for a field of view of 24 cm and a nominal 1.5x1.5-cm2 in-plane resolution. Measurements were performed with 17 CS encoding steps in t1 (Deltat1=12.8 ms) and an average echo time of 151 ms, which was determined by simulating the CT-PRESS experiment for the spin systems of glutamate (Glu) and myo-inositol (mI). Signals from N-acetyl-aspartate, total creatine, choline-containing compounds (Cho), Glu, and mI were detected in a healthy volunteer with no or only minor baseline distortions within 14 min on a 3 T MR scanner.  相似文献   
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Sonoelasticity imaging of prostate cancer: in vitro results   总被引:2,自引:0,他引:2  
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The present study evaluated the use of psychologic measures, in particular, the relatively new Million Behavioral Health Inventory (MBHI), in predicting change in physical function of chronic low back pain patients undergoing a functional restoration program. The first 134 consecutive patients completing this program were assessed. Results demonstrated that various clinical scales of the MBHI were predictive of improvement in physical function. In addition, various scales enabled discrimination between patients who completed the program and those who prematurely dropped out. Although this inventory shows promise in helping to predict response to treatment, no single psychologic test can reliably be used as the sole predictor in clinical cases.  相似文献   
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For chronic thromboembolic pulmonary hypertension not amenable to pulmonary endarterectomy, effective medical therapy is desired. In an open-label uncontrolled clinical trial, 104 patients (mean +/- sem age 62 +/- 11 yrs) with inoperable chronic thromboembolic pulmonary hypertension were treated with 50 mg sildenafil t.i.d. At baseline, patients had severe pulmonary hypertension (pulmonary vascular resistance 863 +/- 38 dyn.s.cm(-5)) and a 6-min walking distance of 310 +/- 11 m. Eight patients were in World Health Organization functional class II, 76 in class III and 20 in class IV. After 3 months' treatment, there was significant haemodynamic improvement, with reduction of pulmonary vascular resistance to 759 +/- 62 dyn.s.cm(-5). The 6-min walking distance increased significantly to 361 +/- 15 m after 3 months' treatment, and to 366 +/- 18 m after 12 months' treatment. A subset of 67 patients received a single dose of 50 mg sildenafil during initial right heart catheterisation. The acute haemodynamic effect of this was not predictive of long-term outcome. In this large series of patients with inoperable chronic thromboembolic pulmonary hypertension, open-label treatment with sildenafil led to significant long-term functional improvement. The acute effect of sildenafil may not predict the long-term outcome of therapy.  相似文献   
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We evaluated the consistency of three questionnaire methods of assessing work and leisure activity in the rural biethnic population of the San Luis Valley Diabetes Study. A 7-d physical activity recall (PAR), a ranking of usual activity, and a history of usual participation in vigorous activity were used. Energy expenditure (kJ.kg-1.wk-1) (EE) was estimated from PAR. Subjects were 503 adults [49% non-Hispanic white (NHW), 51% Hispanic]. Physical activity at work rather than leisure-time activity largely determined total energy expenditure. Average EE at work increased with work rank for all subjects combined [mean EE (SEE) for rank 1 (low) = 324.2 (24.4), rank 4 (high) = 874.0 (102.1)] and within sex, ethnic, and occupational subgroups. Leisure EE increased with leisure rank only for NHW men and employed women. Similar patterns were observed in comparisons of PAR data with history of vigorous activity. Further development and validation of instruments appropriate for use across population subgroups are needed.  相似文献   
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