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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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Smoking behavior among participants in the nurses' health study.   总被引:2,自引:1,他引:1       下载免费PDF全文
We analyzed smoking behavior of 91,651 married female nurses, aged 30-55 years in 1976. The prevalence of smoking was similar among all birth cohorts. The largest percentage increase in starting to smoke occurred between ages 15 and 25 years; by age 25, 50 per cent had started smoking. The cessation rate was lowest in earlier birth cohorts and among nurses starting to smoke at earlier ages. The cessation rate increased substantially between 1963-73 compared with the period 1948-58.  相似文献   
4.
The quadriceps tendon and patellar tendon (ligament) were repaired with a Dacron vascular graft used as a tension suture material. In cases of quadriceps tendon ruptures, the Dacron graft is passed transversely through the patellar ligament just below the patella and crossed transversely at the level of the musculotendinous junction with two loops applying tension to the tendon, which brings the tendon ends together by creating a solid structure. In cases of patellar ligament ruptures, the Dacron graft is passed through a hole in the tibia posteriorly to the tibial tuberosity instead of through the patellar ligament below the patella. This technique enables early mobilization on the first day after surgery. The technique was first tested on six dogs with severed quadriceps tendons and patellar ligaments that were repaired with this suture method. All of the animals recovered from surgery and walked and ran normally on the repaired legs within 27 days and with only mild limping after 17 days. The technique was then used on six patients, four with complete quadriceps tendon rupture and two with complete tear (avulsion) of the patellar ligament (tendon). In all of the patients, excellent surgical results were obtained and leg immobilization was virtually eliminated. Physical therapy was prescribed the first day after surgery. The rehabilitation period was significantly reduced.  相似文献   
5.
The role of several hippocampal innervations in the sensitivity to barbital-induced narcosis was studied in selected mice strains. The outbred and inbred mouse strains HS/Ibg, SABRA/HUC, C57BL, CBA/LAC, and BALB/c were tested for barbital-induced sleep (315 mg/kg). The relatively short sleeping HS/Ibg (HS) and the longest sleeping BALE/c (BALE) were chosen for further investigation. Cholinergic (ACh), serotonergic (5-HT), and noradrenergic (NE) innervations were studied in HS strain; whereas BALE, which possesses both an unusually high sensitivity to barbital and unique NE innervations in the cortex and hippocampus, was employed in a detailed study of the NE innervations. Transplantation of embryonic NE cells from the mouse embryo into the hippocampus of adult HS mice increased barbital narcosis by 65% (p < 0.05), whereas transplantation of 5-HT cells decreased barbital narcosis by 54% (p < 0.001). Transplantation of ACh cells had no significant effect on barbital-induced narcosis. BALB mice were subjected to NE cell transplantation into the hippocampus and cortex. Similarly to HS, BALB receiving NE transplants into their hippocampus slept 34% longer than control after barbital challenge (p < 0.025). Noradrenergic cell transplantation into frontal cortex had no effect on barbital sleep. The results suggest that (a) enhancement by neural grafting of the NE innervation to the hippocampus accentuates and enhancement of the 5-HT innervations attenuates the sensitivity to barbital narcosis, whereas ACh innervations have no effect on the sensitivity to barbital narcosis, and (b) the unusually high sensitivity of BALB mice to barbital may not be related to its unique NE innervations.  相似文献   
6.
Prospective study of relative weight, height, and risk of breast cancer   总被引:1,自引:0,他引:1  
We examined relative weight and height in relation to subsequent breast cancer risk among 115,534 women 30 to 55 years of age and free from cancer in 1976. By 1984, six hundred fifty-eight premenopausal and 420 postmenopausal breast cancers were documented during 734,716 person-years. Among premenopausal women, risk of breast cancer decreased significantly with increasing relative weight (relative risk for the highest category was 0.6). A similar inverse association was seen for recalled relative weight at 18 years of age. Postmenopausal breast cancer was not associated with relative weight, either recent or at age 18. Height was not associated with breast cancer risk among premenopausal women and only weakly related among postmenopausal women. These data suggest that obesity among premenopausal and early postmenopausal women does not increase breast cancer risk substantially.  相似文献   
7.
The reproducibility and validity of self-reported menopausal status were evaluated among the 121,700 female US registered nurses aged 30-55 years in 1976 who are participants in the Nurses' Health Study, a prospective cohort study of diseases in women. When questioned in 1978, 6,591 of the women who were premenopausal in 1976 reported that their menses had ceased and provided their age at menopause. Two years later, in 1980, 98.8 per cent of the 6,591 women again reported that they were postmenopausal and again gave the reasons for menopause (natural or surgical). Among those women who reported surgical menopause during the 1976-1978 follow-up interval, age at menopause was reported to within one year on both the 1978 and 1980 questionnaires by 95 per cent of women. Among those reporting natural menopause during the 1976-1978 period, 82 per cent of women reported their age at menopause to within one year on the two follow-up questionnaires. A random sample of 255 women reporting surgical menopause between 1982 and 1984 was identified and medical records were obtained for 200. For all but two women, there was complete agreement between self-report and medical record for details of hysterectomy and extent of ovarian surgery. The reproducibility of self-reported age at menopause was assessed among 31,405 women who were menopausal in 1976. Reported age at menopause on consecutive questionnaires showed increasing within-person variance with increasing duration since menopause.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Malignant thymomas are among the least common mediastinal tumors in the pediatric age group. Thymomas are considered malignant on the basis of macroscopic and microscopic invasiveness. As only 20 well-documented cases involving children have been reported in the literature, the pattern of responsiveness to therapy and the value of prognostic signs is obscure. Two cases of malignant pediatric thymomas are reported with pathognomonic histoimmunological features of aggressive thymoma. One was cured, with a follow-up of 70 months, and one died while on therapy. Analysis of the histological features and the immunoperoxidase staining displays the complexity of pediatric thymomas and the inability to prognosticate the outcome, respectively.  相似文献   
10.
Familial clustering of insulin sensitivity.   总被引:5,自引:0,他引:5  
This study's objective was to determine whether there is familial clustering of insulin sensitivity (SI) or insulin-independent glucose uptake (SG), which would be evidence that they are genetically determined traits. Outpatients had a 3-h intravenous glucose tolerance test. Nondiabetic individuals (n = 183), ranging in age from 16 to 60 yr, were from 105 families that had 2 parents with non-insulin-dependent diabetes mellitus. Of these families, 62 contributed 1 offspring, 21 contributed 2, 13 contributed 3, 6 contributed 4, and 2 and 1 contributed 5 and 6, respectively. The minimal model of glucose disposal and the glucose and insulin values from the intravenous glucose tolerance tests were used to estimate SI and SG. The intraclass correlation coefficient was used to compare the within-family variability of SI and SG with the respective between-family distributions. The intraclass correlation coefficients were 0.26 (P = 0.008) for SI and 0.081 (P = 0.45) for SG. SI and SG were uncorrelated (r = -0.059, P = 0.42). The intraclass correlation of SI could not be explained by familial clustering of fasting insulin or ideal body weight. Finally, the 10 families with the lowest values of SI had a significantly higher within-sibship variability of SI than the other 33 families (P less than 0.001, F test). SI but not SG showed familial clustering, which is consistent with a polygenic determinant of SI. In addition, a large within-family variability of SI in some families is compatible with a major gene effect with a dominant mode of inheritance.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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