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71.
The authors have developed a new technique for the stereotactic clipping of the feeding vessels of deep-seated arteriovenous malformations (AVM), for use when direct attack may be very dangerous or impossible. A special clipping device and the technique for its application are described. The instrument is introduced through a burr hole using the stereotactic apparatus designed by the authors. The clipping is monitored by intraoperative angiography. The method was used in 32 patients with supratentorial AVMs. It is concluded that in selected cases the method is effective, is less traumatic and gives successful results.  相似文献   
72.
Background:The best therapeutic option for unruptured brain arteriovenous malformations (bAVMs) patients is disputed.Objective:To assess the occurrence of obliteration and complications of patients with unruptured bAVMs after various treatments.Methods:A systematic literature search was performed in PubMed, EMBASE, Web of Science, and so on to identify studies fulfilling predefined inclusion criteria. Baseline, treatment, and outcomes data were extracted for statistical analysis.Results:We identified 28 eligible studies totaling 5852 patients. The obliteration rates were 98% in microsurgery group (95% confidence interval (CI): 96%–99%, I2 = 74.5%), 97% in surgery group (95%CI: 95%–99%, I2 = 18.3%), 87% in endovascular treatment group (95%CI: 80%–93%, I2 = 0.0%), and 68% in radiosurgery group (95%CI: 66%–69%, I2 = 92.0%). The stroke or death rates were 1% in microsurgery group (95%CI: 0%–2%, I2 = 0.0%), 0% in surgery group (95%CI: 0%–1%, I2 = 0.0%), 4% in endovascular treatment group (95%CI: 0%–8%, I2 = 85.8%), and 3% in radiosurgery group (95%CI: 3%–4%, I2 = 82.9%). In addition, the proportions of hemorrhage were 2% in microsurgery group (95%CI: 1%–4%, I2 = 0.0%), 23% in endovascular treatment group (95%CI: 7%–39%), and 12% in radiosurgery group (95%CI: 12%–13%, I2 = 99.2%). As to neurological deficit, the occurrence was 9% in microsurgery group (95%CI: 6%–11%, I2 = 94.1%), 20% in surgery group (95%CI: 13%–27%, I2 = 0.0%), 14% in endovascular treatment group (95%CI: 10%–18%, I2 = 64.0%), and 8% in radiosurgery group (95%CI: 7%–9%, I2 = 66.6%).Conclusions:We found that microsurgery might provide lasting clinical benefits in some unruptured bAVMs patients for its high obliteration rates and low hemorrhage. These findings are helpful to provide a reference basis for neurosurgeons to choose the treatment of patients with unruptured bAVMs.  相似文献   
73.
目的:探讨CT血管成像对脑静脉的诊断价值。方法:使用64层螺旋CT对18例脑静脉畸形患者进行CT血管成像检查。并对经CT扫描图像进行最大密度投影、容积再现、多平面重组。结果:CT血管成像能准确显示脑静脉畸形的部位与病变形态;清晰显示脑静脉畸形血管的构成、引流静脉的方向和数目;并且能有效显示血管巢、供血动脉和引流静脉。结论:CT血管成像操作经济、快速、简单、无创伤性,是诊断脑静脉畸形的有效方法,对脑静脉畸形的诊断有非常重要的临床价值。  相似文献   
74.
非黏附性液体栓塞剂治疗脑动静脉畸形   总被引:1,自引:0,他引:1  
目的 探讨新型液态栓塞剂Onyx栓塞脑动静脉畸形的技术要点和临床效果。方法 对21例脑动静脉畸形患者采用Seldinger技术在股动脉内置入6F鞘,6F导引导管进入颈内动脉或椎动脉。以Ultraflow微导管超选择进入畸形团内,采用“阻断和前推技术”长时间缓慢注射Onyx栓塞脑动静脉畸形。本组患者中有13例动静脉畸形位于功能区(运动区、语言区、视觉中枢),6例位于大脑半球深部,2例位于小脑半球。畸形团大小为3cm的9例,3~6cm的8例,6cm以上的4例。结果 治疗后脑动静脉畸形的体积缩小程度为20%~100%。初期因使用Onyx经验不足,在拔出微导管时有2例患者发生严重脑出血.行外科手术救治,其余19例患者无严重并发症。结论 Onyx栓塞技术可作为治疗体积较大、位于大脑深部及功能区脑动静脉畸形的重要方法之一,长期疗效有待随访结果的验证。  相似文献   
75.
Aims Insulin glargine (IG), with its non‐peaking action profile, might be useful in diabetic pregnancy. However, data on its safety are limited and its use during pregnancy is not recommended. This study focused on the effects of IG on perinatal outcome, particularly to estimate the rate of congenital anomalies and birthweight. Methods This retrospective study included women with pre‐gestational diabetes who used IG before (at least 1 month) and during pregnancy. For all women we recorded data regarding maternal glycaemic control and pregnancy outcome. We also compared women treated with IG throughout pregnancy and women who stopped taking IG at an earlier stage. Results From 27 centres, 107 Type 1 diabetic pregnancies were identified. IG was started 10.3 ± 6.9 months before conception and in 57.4% of cases was stopped during the first trimester; 42.6% of women continued using it until the end of pregnancy. There were six abortions (four spontaneous and two induced) and five newborns (4.9%) with congenital anomalies. Glycaemic control, birthweight and the prevalence of macrosomia and neonatal morbidity were similar in women who used IG for the full term compared with those who stopped IG earlier during pregnancy. Conclusions This study, although limited, suggests that IG is safe and effective; the rate of congenital malformations was within the range expected for diabetic pregnancies treated with more traditional forms of insulin. IG used throughout pregnancy did not seem to influence birthweight or increase adverse outcomes.  相似文献   
76.
目的 观察胎儿中线处硬脑膜窦畸形(DSM)的产前超声与MRI特征。方法 回顾性分析5胎经产前超声及MRI诊断为脑中线处DSM胎儿,并与引产尸检结果对照,观察中线处DSM的产前影像学特征。结果 产前超声诊断3胎DSM,其中1例合并血栓形成;5胎均表现为中线处囊性回声肿物,其中4胎于扩张的静脉窦内见云雾状细密点状回声;合并血栓者于囊性回声区内见高回声团块,CDFI未见明显血流信号。产前MRI诊断5胎均为DSM,其中2胎合并血栓形成;4胎主要表现为中线处窦汇区三角形或楔形瘤样扩张,并向邻近上矢状窦后部延伸,T1WI多呈等或高信号、T2WI多呈低信号,合并血栓时周围可见低信号环绕。5胎均接受引产,1胎尸检见胎儿上矢状窦偏后部及窦汇区呈瘤样扩张及血栓形成。结论 胎儿中线处DSM具有典型产前超声与MRI表现;产前超声不能除外胎儿DSM时,建议行MR检查。  相似文献   
77.
This review will discuss conventional and advanced magnetic resonance (MRI) imaging techniques used to study the spine and spinal cord according to the anatomical structures and clinical indications. Clinical challenges that neuroradiologists may face are also discussed, such as the “when” and “where” concerning the use of each technique, and in which pathology or clinical scenario each technique is useful. Finally, some “tips and tricks” to overcome the challenges are provided with clinical examples.  相似文献   
78.
Asymptomatic dural arteriovenous fistulas (DAVFs) with cortical venous reflux (CVR) are now more commonly encountered. However, patients with an incidental onset may have a less aggressive clinical course. It is desirable to explore methods and indicators to predict the clinical outcomes. This study investigates whether the relative signal intensity (rSI) of the draining vessels on the time-of-flight magnetic resonance angiography is related to clinical behavior in patients with intracranial DAVFs. We retrospectively reviewed 36 intracranial DAVFs. The patients were categorized as those with either aggressive-presentation or non-aggressive-presentation (n = 16 and 20, respectively). The rSIs of the shunt points, affected sinuses, and veins with CVR were compared between the two groups. The two groups were not significantly different in terms of rSIs of the shunt points and affected sinuses (p = 0.37 and 0.41, respectively). However, a significant positive correlation was observed in the rSI of the veins with CVR between the aggressive and non-aggressive behavior groups (p < 0.0001). The rSI of the veins with CVR could serve as a reliable indicator of aggressive behavior in intracranial DAVFs, and its optimal cutoff value was 1.63 with high sensitivity and specificity for predicting aggressive behavior (area under the curve, 0.909).  相似文献   
79.
Deep-seated intracranial arteriovenous malformations (AVMs) represent a subset of AVMs characterized by variably reported outcomes regarding the risk of hemorrhage, microsurgical complications, and response to stereotactic radiosurgery (SRS). We aimed to compare outcomes of microsurgery, SRS, endovascular therapy, and conservative follow-up in deep-seated AVMs. A prospectively maintained database of AVM patients (1990–2017) was queried to identify patients with ruptured and unruptured deep-seated AVMs (extension into thalamus, basal ganglia, or brainstem). Comparisons of hemorrhage-free survival and poor functional outcome (modified Rankin scale [mRS] > 2) were performed between conservative management, microsurgery (±pre-procedural embolization), SRS (±pre-procedural embolization), and embolization utilizing multivariable Cox and logistic regression analyses controlling for univariable factors with p < 0.05. Of 789 AVM patients, 102 had deep-seated AVMs (conservative: 34; microsurgery: 6; SRS: 54; embolization: 8). Mean follow-up time was 6.1 years and did not differ significantly between management groups (p = 0.393). Complete obliteration was achieved in 49% of SRS patients. Upon multivariable analysis controlling for baseline rupture with conservative management as a reference group, embolization was associated with an increased hazard of hemorrhage (HR = 6.2, 95%CI [1.1–40.0], p = 0.037), while microsurgery (p = 0.118) and SRS (p = 0.167) provided no significant protection from hemorrhage. Controlling for baseline mRS, microsurgery was associated with an increased risk of poor outcome (OR = 9.2[1.2–68.3], p = 0.030), while SRS (p = 0.557) and embolization (p = 0.541) did not differ significantly from conservative management. Deep AVMs harbor a high risk of hemorrhage, but the benefit from intervention Remains uncertain. SRS may be a relatively more effective approach if interventional therapy is indicated.  相似文献   
80.
Mosaic Variegated Aneuploidy Syndrome 2 (MVA2; MIM 614114) is a rare autosomal recessive disorder, characterized by mosaic aneuploidies involving multiple chromosomes and tissues, caused by biallelic pathogenic variants in the CEP57 gene. Only 10 patients have been reported to date. We report two additional non related cases born to Moroccan consanguineous parents, carrying the previously described c.915_925dup11 CEP57 homozygous variant. Common features of these 12 cases include growth retardation, typically of prenatal onset, distinctive facial features, endocrine, cardiovascular and skeletal, abnormalities while malignancies have not been reported. This report describes the phenotypical spectrum of MVA2.  相似文献   
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