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991.
《Journal of cranio-maxillo-facial surgery》2014,42(7):1480-1485
ObjectiveDental arcade arteriovenous fistula (DA-AVF) are rare. The purpose of this study was to understand the angioarchitecture of these lesions, changing strategies of endovascular treatment and to analyse the best therapeutic option which will allow normal skeletal development especially in children.Materials and methodsRetrospective study of all the patients of DA-AVF managed at our centre over the last 16 years. Detailed analysis of the clinical features, the imaging findings, endovascular treatment and angiographic outcomes was done.ResultsTotal of six patients were treated. 5 were in the mandible and one in the maxilla. Transarterial glue embolization was done in 3 patients and direct puncture of the intraosseous venous pouch in 2. Transarterial Onyx was used in 2 patients through dual lumen balloon catheter. Overall cure was achieved in 5 out of 6 patients (83%).ConclusionHigh index of suspicion is required to diagnose it on panoramic radiographs. CT/MR/CTA can lead to early diagnosis. Transarterial Onyx embolization using dual lumen balloon catheter is a promising technique & allows excellent penetration of Onyx into the intraosseous venous pouch. 相似文献
992.
《Journal of cranio-maxillo-facial surgery》2014,42(8):1964-1969
Minimally invasive surgical approaches to parotid stones (such as extra-corporeal shockwave lithotripsy and sialendoscopy) have proved to be effective in a high percentage of cases, although success depends on factors such as the localisation of the stone, its size and its mobility. The failure rate of 10% is largely due to large and impacted stones and, in such cases, a combined external and sialendoscopic approach can be used to avoid morbidity and the risks of more invasive superficial parotidectomy. We treated eight patients with large parotid stones (>7 mm) using a sialendoscopy-assisted transfacial surgical approach that was effective in all but one case, which was successfully solved by combining this procedure with extra-corporeal lithotripsy and operative sialendoscopy. Our results confirm that the combined approach is a valid alternative to parotidectomy for large parotid stones and should be added to other minimally invasive techniques aimed at restoring the function of the affected parotid gland. 相似文献
993.
《Orthopaedics and Trauma》2014,28(1):41-49
The knee joint is particularly vulnerable to injury or damage as it supports the full weight of the body. Thus, conditions affecting the knee can be debilitating. History, clinical examination, laboratory investigations and radiological findings help complete the picture and establish a definite diagnosis. The choice of the appropriate imaging method depends on the differential diagnosis, availability and urgency of a radiological investigation. It is also important to consider how the imaging findings will affect prognosis and management. In the review that follows an overview of the most common knee pathologies alongside the most significant findings in various imaging modalities is provided. 相似文献
994.
995.
目的分析慢性主髂动脉闭塞(Leriche综合征)的CT表现,总结该病侧支动脉开放类型,提高对慢性Leriche综合征的认识。方法回顾性收集本院2016年1月~2018年9月确诊为慢性Leriche综合征患者36例。36例患者治疗前均行主动脉CTA检查。24例行主动脉-股动脉人工血管旁路移植术和6例行介入治疗(球囊扩张和/或支架成形术);6例行内科治疗。结果36例主髂动脉CTA均表现为腹主动脉-髂总动脉分叉闭塞,根据闭塞近心端(上端)位置分3型:(1)近肾动脉旁型16例;(2)肠系膜下动脉上型8例;(3)肠系膜下动脉下型12例。全部病例闭塞或次全闭塞远心端(下端)达单侧或双侧髂内、外动脉水平。36例慢性Leriche综合征侧支动脉开放类型有5种:(1)A型(Winslow通路,出现率100%,36/36),开放侧支为双侧腹壁上动脉,通过胸廓内动脉与腹壁下动脉吻合,连接于髂外动脉。(2)B型(出现率92%,33/36):开放侧支为双侧下肋间动脉、肋下动脉/腰动脉,通过旋髂深动脉连接髂外动脉或股动脉。(3)C型(出现率50%,18/36):开放侧支为肠系膜上动脉分支(中结肠动脉),通过Riolan弓连接肠系膜下动脉或其分支直肠上动脉。(4)D型(出现率36%,13/36):开放侧支为双侧或单侧肋下动脉,通过髂腰动脉连接髂内动脉。(5)E型(出现率53%,19/36):开放侧支为直肠上动脉,通过骶动脉丛/直肠下动脉连接髂内动脉。A型和B型侧支动脉的开放可提供下腹壁和下肢动脉的血供。C型出现于闭塞近端位于肠系膜下动脉以上的患者,以代偿肠系膜下动脉供血区的血运。D型和E型为少见类型。结论慢性Leriche综合征患者的侧支动脉开放有多种类型,侧支动脉开放与主髂动脉闭塞范围相关。正确识别和描述侧支动脉有助于为临床提供更全面的诊断信息。 相似文献
996.
目的探讨负荷动态CT心肌灌注结合冠状动脉CT血管成像对冠心病心肌缺血的诊断价值。方法选取2017年4月至2019年4月收治的96例冠心病心肌缺血患者为研究对象,随机将其等分为研究组和对照组,对照组采取冠状动脉CT血管成像检查,研究组采取负荷动态CT心肌灌注结合冠状动脉CT血管成像检查,比较两组使用造影剂剂量及放射剂量,斑块导致管腔狭窄比例、斑块长度以及诊断率。结果研究组患者造影剂剂量、放射剂量均明显低于对照组,差异有统计学意义(P<0.05);研究组患者斑块导致管腔狭窄比例、斑块长度、诊断率均明显高于对照组,差异有统计学意义(P<0.05)。结论冠心病心肌缺血患者联合应用冠状动脉CT血管成像与负荷动态CT心肌灌注,可在降低造影剂和放射剂量的情况下,明确冠状动脉狭窄和斑块病变情况,提高对疾病的临床诊断价值。 相似文献
997.
目的采用受试者工作特征曲线(ROC曲线)对比分析超微血管显像(SMI)技术与超声造影在乳腺导管内乳头状瘤的诊断价值。方法设计前瞻性随机对照研究,研究对象选取该院2017年1月到2019年1月收治的50例诊断为乳腺导管内乳头状瘤患者和50例同期乳腺超声检查发现乳腺导管扩张(经病理诊断为非乳腺导管内乳头状瘤)患者。所有患者均完成SMI技术检查以及超声造影检查。观察SMI技术与超声造影在乳腺导管内乳头状瘤诊断的影像学表现,并采用ROC曲线分析二者诊断价值差异。结果SMI技术检查微血管筑型:无血管52例,线型30例,树枝型13例,残根型5例;共诊断乳腺导管内乳头状瘤48例,非乳腺导管内乳头状瘤52例;诊断灵敏度为84.00%,特异度为88.00%,准确率为86.00%。超声造影病灶回声无增强51例,均匀增强28例,区域增强16例,不均匀增强5例,共诊断乳腺导管内乳头状瘤49例,非乳腺导管内乳头状瘤51例;诊断灵敏度为88.00%,特异度为90.00%,准确率为89.00%。SMI检出率(84.00%)低于超声造影(86.00%),但组间比较差异无统计学意义(χ^2=0.078,P=0.779)。SMI技术与超声造影在乳腺导管内乳头状瘤诊断Kappa一致性检验结果提示Kappa=0.78,说明SMI技术和超声造影技术对乳腺导管内乳头状瘤的诊断具有一致性。SMI技术诊断ROC曲线下面积(AUC)=0.860,95%CI:0.781~0.939;超声造影技术诊断AUC=0.890,95%CI:0.819~0.961;SMI技术与超声造影在乳腺导管内乳头状瘤诊断价值相当(P>0.05)。结论SMI技术与超声造影在乳腺导管内乳头状瘤诊断价值相当,但SMI技术诊断更便捷,且为无创检查,值得在临床推广应用。 相似文献
998.
目的探讨磁共振血管造影(magnetic resonance angiography,MRA)中侧枝血管与急性卒中机械取栓术后预后间的关系。材料与方法前瞻性纳入接受机械取栓治疗的急性卒中患者。所有患者均于治疗前及治疗后24 h内接受头颅MRI平扫和MRA检查。3个月后的预后情况根据改良Rankin量表(modified Rankin Scale,mRS)评估,mRS0~2为预后良好组,mRS3~6为预后不良组。统计学方法分析预后良好组与不良组之间侧裂及软脑膜的侧枝血管的差异。结果共55例动脉闭塞的卒中患者纳入分析(侧裂侧枝血管不丰富者52例,软脑膜侧枝血管不丰富者45例)。侧裂血管和软脑膜血管不丰富的患者,预后良好组的入院NIHSS评分(10.06±4.65 vs 14.25±4.91;P=0.006)、术前梗死体积(13.61±10.99 vs 59.80±92.74;P=0.006)均低于预后不良组。多元逻辑回归分析显示年龄、软脑膜的侧枝循环是预测预后的独立预测因子(OR=1.094,95%CI=1.025~1.168,P=0.007;OR=9.542,95%CI=1.812~50.245,P=0.008)。预后良好组的梗死增长体积(术前vs术后:14.15±10.73 vs 21.39±17.41)小于预后不良组(术前vs术后:16.88±16.64 vs 57.27±56.67),然而多元逻辑回归分析显示术后梗死体积对预测卒中预后无显著意义(OR=1.094,95%CI=1.025~1.168,P=0.154)。结论磁共振血管造影侧枝血管可用于评估卒中预后,尤其是软脑膜的侧枝循环可预测卒中预后,而术后卒中梗死体积与预后的关系仍需进一步研究。 相似文献
999.
目的探讨无创肢体远端缺血预处理对经桡动脉行冠状动脉介入诊疗术(transradial angiography and intervention,TAI)后患者舒适程度的影响。方法采用便利抽样法,选取2018年6—12月在新疆医科大学第一附属医院冠心病二科住院的冠心病患者160例,所有患者均行TAI。按照随机数字表法将患者分为对照组80例、干预组80例。对照组给予常规护理,干预组给予常规护理和术前24 h内无创肢体远端缺血预处理干预3次。观察两组患者术后24 h内外周血管并发症及舒适度的差异。结果TAI术后12 h两组患者肿胀程度、疼痛程度差异有统计学意义(P<0.05)。TAI术后24 h内两组患者均未发生骨筋膜室综合征;两组患者桡动脉闭塞、局部出血发生情况比较差异无统计学意义(P>0.05);两组患者桡动脉狭窄、迷走神经反射发生情况比较差异有统计学意义(P<0.05)。结论无创肢体远端缺血预处理能有效减少TAI诊疗患者术后桡动脉狭窄等并发症的发生,提高患者术后的舒适度。 相似文献
1000.
《Journal of Medical Imaging and Radiation Sciences》2020,51(3):480-488
IntroductionThis study presents and evaluates a CT pulmonary angiography protocol dedicated to pregnant women. The specific feature of this protocol is to place the region of interest (ROI) (bolus detection) in the superior vena cava. The objective is to evaluate the performances of this method.Materials and methodsThe protocol uses a iodine-based contrast agent at 300mgI/mL and an injection rate of 5 to 6 mL/sec for an injection volume of 50 mL of iodine contrast agent followed by 40 mL of NaCl. The ROI is positioned on the superior vena cava, with a 100 Hounsfield units (HU) threshold, and the acquisition is performed at 100 kVp. This protocol was evaluated retrospectively on a large population (n = 105: group 1) and compared with a control group that did not benefit from this protocol (n = 55: group 2). Both groups were studied on the same device in the same center. Each examination was evaluated and classified into 3 groups: optimal, suboptimal, and noncontributory. Dose length products (DLP) values were also recorded. Statistical tests were applied to the data collected.ResultsThe rate of noncontributory examinations increased from 43.1% for the control group to 4.8% for the new protocol group. The reference enhancement level in the pulmonary trunk is 250 UH. The mean enhancement in the pulmonary trunk of the new protocol group (332 HU (±71 HU (±71 HU)) is significantly greater than the reference value of 250 HU (P < .0001), which is not the case for control group (P = .3485 > .05), which has a mean enhancement of 239 HU (±87 HU). The control group had a mean DLP of 225 mGy.cm (±81 mGy.cm), and the new-protocol group had a mean DLP of 189 mGy.cm (±75 mGy.cm).DiscussionOur noncontributory examination rate is the lowest rate described in the literature. Our protocol contradicts standard practices of placing an ROI in the pulmonary trunk for bolus detection of iodinated contrast media.ConclusionThe results of this study showed that this protocol reduces the number of noncontributory examinations while reducing the dose delivered to patients. This robust protocol is applicable to other devices and meets perfectly radiation-safety requirements and injected contrast media volume limitation. 相似文献