虚拟器械及脑动脉瘤模型在介入术前模拟中的价值

目的探讨器械及脑动脉瘤的虚拟三维模型在神经介入术前模拟中的作用。方法在标准脑动脉瘤虚拟三维模型基础上，结合个体化的DSA资料，应用三维造型软件3DStudio MAX R3创建虚拟的个体化脑动脉瘤模型，并建立虚拟的导丝、导管、支架和弹簧圈，在计算机上进行神经介入手术前的模拟研究，并与3例患者的实际手术结果进行比较。结果3例术前模拟确定的工作角度、导管导丝头端塑型的角度均与手术结果相同；2例（前交通动脉瘤和后交通动脉瘤各1例）所需弹簧圈数目、尺寸的模拟结果与手术结果相同，1例（颈内动脉巨大动脉瘤）瘤体的弹簧圈模拟结果比手术结果多2枚3mm×3cm的三维弹簧圈，并且术中对瘤颈第2枚弹簧圈的释放进行了实时模拟调整；术后回顾性模拟显示对于瘤体较规则、体积较小的动脉瘤，其模拟方法可作为常规的模拟训练手段，对于体积较大的动脉瘤，其模拟训练方法尚需积累更多经验。结论由软件方法建立的虚拟器械及个体化的虚拟脑动脉瘤模型为神经介入的术前模拟、术中指导及介入操作技术培训提供了一种新的工具．对开展神经介入手术具有重要的实用价值。     

颅内动脉瘤栓塞术中出血易忽视的影像表现——血流变慢

目的分析颅内动脉瘤弹簧圈栓塞治疗术中出血的影像学表现。方法回顾性分析358例颅内动脉瘤采用介入栓塞治疗患者病史及造影资料,其中10例术中出血。10例中4例利用支架辅助弹簧圈栓塞术,2例双导管弹簧圈栓塞术,4例单纯弹簧圈栓塞术治疗。结果 8例弹簧圈栓塞过程中出血,出血表现为对比剂外溢,载瘤血管一过性血流变慢,其中5例弹簧圈突出瘤壁,1例微导管突出瘤壁外,2例微导丝突出瘤壁外;另2例为弹簧圈栓塞中造影仅见血流明显变慢,未见对比剂外溢及微导管、微导丝和弹簧圈突出瘤壁,术后CT证实为出血。10例术中破裂者中9例致密栓塞,1例部分栓塞,术后对症治疗7例,开颅引流减压3例。6例恢复好,1例一过性动眼神经麻痹,3例死于颅内压增高。结论术中出血导致的载瘤血管血流变慢易被忽视,而此征象与患者预后密切相关。     

微导丝辅助技术在颅内动脉瘤栓塞治疗中的应用研究

目的 探讨微导丝辅助的瘤颈成形技术在弹簧圈栓塞治疗颅内动脉瘤中的价值、技术操作要点及临床应用前景。方法 本组包括25例小型宽颈动脉瘤(前交通动脉12例，大脑中动脉分叉部12例，小脑后下动脉瘤1例)。微导管成功超选动脉瘤囊内，将撤出的微导丝再塑形后跨瘤颈部位放置。通过微导管内用电解可脱卸弹簧圈栓塞动脉瘤。结果 25例均获得成功，动脉瘤致密栓塞，载瘤动脉保持通畅，效果满意。短期影像随访16例，动脉瘤无复发。结论 微导丝瘤颈成形术作为小型宽颈动脉瘤治疗技术是安全、经济有效的。     

大脑中动脉分叉部动脉瘤的介入治疗

目的　总结大脑中动脉分叉部动脉瘤影像学特征、血管内栓塞治疗技巧及结果。方法　采用微弹簧圈栓塞治疗大脑中动脉分叉部动脉瘤 194例 ,对宽颈动脉瘤则采用瘤颈成形辅助技术 ,其中球囊辅助成形术 17例 ,微导丝辅助成形技术 19例 ,支架结合弹簧圈栓塞 2 1例。结果　栓塞程度 :致密栓塞 134例 (6 9% ) ,90 %以上 38例 (2 0 % ) ,90 %以下 2 2例 (11% )。术中出血 9例 (4 .6 % ) ,死亡 1例 (0 .5 % )。结论　GDC栓塞大脑中动脉分叉部动脉瘤具有微创、安全、效果可靠的优点。采用微导丝辅助瘤颈成形技术、瘤颈重塑形技术、血管内支架等方法 ,可以明显提高宽颈动脉瘤的致密栓塞率和减少脑梗死并发症。     

Neuroform3支架在急诊血管内栓塞破裂性颅内宽颈动脉瘤中的应用

目的 评价急诊血管内Neuroform3支架辅助下可解脱弹簧圈栓塞破裂的颅内宽颈动脉瘤的疗效和中期随访.方法 回顾性分析最近18个月急诊介入栓塞治疗的破裂出血性颅内动脉瘤48例,其中26例在72 h内实施Neuroform3支架辅助下弹簧圈栓塞术.其中3例动脉瘤位于大脑前动脉A1段,3例位于大脑中动脉M1和M2段,13例位于后交通,2例位于颈内动脉眼动脉段,2例位于基底动脉顶端,2例位于椎动脉V2和V4段,1例位于小脑后下动脉;3例在第1枚弹簧圈释放后植入支架,1例在第2枚弹簧圈释放后植入支架,2例在第4枚弹簧圈释放后植入支架,10例在第1枚弹簧圈无法在瘤腔内成篮后植入支架,其余10例先植入支架再进行弹簧圈栓塞,所有微导管均通过支架网眼进入动脉瘤.结果 所有病例均成功释放支架(100%),覆盖了瘤颈,同期行弹簧圈填塞动脉瘤.术后即刻造影显示动脉瘤完全栓塞23例(88.5%),次全栓塞3例(11.5%);术中1例支架轻度回撤,无血栓事件和动脉瘤再破裂出血发生,所有患者均恢复良好出院.栓塞术后随访到23例,至少复查1次脑血管造影,最多复查3次;完全致密栓塞14例(60.8%)动脉瘤均末显影,6例瘤颈少许显影病例中3例(11.5%)存在血栓形成,次全栓塞1例(3.3%)瘤体再通,另外2例始终稳定,所有病例载瘤动脉通畅,狭窄2例(7.7%),临床上无任何症状,术后所有患者均无再出血.结论 急症血管内应用Neuroform3支架辅助弹簧圈栓塞破裂出血的颅内宽颈动脉瘤足方便的、安全的和有效的.     

前交通动脉瘤的栓塞治疗

目的　总结 2 62例前交通动脉瘤栓塞治疗的经验。方法　均采用电解可脱卸弹簧圈(guglielmidetachablecoil,GDC)作动脉瘤内栓塞治疗。对双侧A1正常者应用双侧颈动脉置管技术监测栓塞术中载瘤动脉通畅情况 ,对瘤颈累及双侧A2者采用微导管微导丝辅助技术保持载瘤动脉通畅。发生术中出血者予弹簧圈继续栓塞 ,发生术中血栓形成者予尿激酶溶栓。 3 4例颅内多发动脉瘤均同次手术治愈。结果　动脉瘤完全闭塞 160例 ,>90 %闭塞 5 6例 ,<90 %闭塞 4 6例。术中因过度栓塞造成载瘤动脉闭塞 10例 ,术后脑梗死 16例。术中发生血栓形成 3例 ,经溶栓后恢复通畅。术后死于肺部并发症 1例 ,植物生存 1例。随访 190例 ,3～ 6个月行DSA/MRA复查 ,动脉瘤复发行 2次栓塞 8例 ,复发经手术治愈 1例 ,其余治疗结果稳定。结论　GDC栓塞治疗前交通动脉瘤效果好。采用微导管 /微导丝辅助技术可提高致密栓塞率和减少脑梗死并发症发生     

新型颅内支架Enterprise结合水解脱弹簧圈栓塞治疗颅内微小宽颈动脉瘤

目的总结应用新型颅内支架Enterprise结合水解脱弹簧圈栓塞治疗颅内微小宽颈动脉瘤的技术及疗效。方法6例颅内微小宽颈动脉瘤(直径<3mm,体/颈比<1.5)采用Enterprise支架结合水解脱弹簧圈栓塞,其中5例采用先放置支架覆盖动脉瘤颈再将微导管经支架网孔放入动脉瘤腔填塞弹簧圈进行栓塞,1例将微导管进入瘤腔后再释放支架进行弹簧圈栓塞。术后3～6个月进行临床随访。结果6例全部技术成功,支架均满意到位,载瘤动脉通畅,无手术并发症;动脉瘤完全闭塞4例,闭塞95%以上2例。术后患者均恢复良好,3～6个月临床随访无再出血及脑血栓形成。结论联合使用Enterprise支架和水解弹簧圈栓塞治疗颅内微小宽颈动脉瘤是一种安全有效的方法,但其长期疗效仍需进一步观察。     

支架联合弹簧圈技术栓塞颅内微小宽颈动脉瘤

目的　探讨三维 (3D)数字减影 (DSA)辅助下血管内支架联合弹簧圈 (stent coil)技术栓塞颅内微小宽颈动脉瘤的技术要点及疗效。方法　 12例瘤体 颈比值≤ 1的颅内微小宽颈动脉瘤 (瘤体最大径≤ 4 .0mm) ,全部经二维 (2D)造影及 3D重建 ,前交通动脉 2例采用双侧置管 ,微导管头端到位后 ,通过对侧导引导管内释放颅内自膨胀支架Neuroform ,再通过微导管使用弹簧圈塞动脉瘤。后交通动脉 8例 ,小脑后下动脉动脉起始部 2例 ,先释放支架覆盖瘤颈 ,通过支架网眼将微导管送入动脉瘤腔使用弹簧圈栓塞 ,术后 6～ 12个月进行临床和影像学随访。结果　 12例 2DDSA检查中 7例需经 3D确定为宽颈动脉瘤 ;12例全部技术成功 ,动脉瘤致密栓塞 ,载瘤动脉通畅 ;1例前交通动脉瘤栓塞后出现一过性神经功能障碍 ,经治疗后恢复正常 ,其余 11例恢复顺利。 12例临床随访 6～ 12个月 ,无动脉瘤再出血或脑血栓形成 ,7例DSA随访 ,无支架内膜增生狭窄及动脉瘤复发。结论　 3DDSA在颅内微小宽颈动脉瘤的诊断和介入治疗中有重要的辅助作用 ,支架～弹簧圈技术栓塞颅内微小宽颈动脉瘤疗效确实 ,颅内专用支架为特殊部位宽颈动脉瘤的介入治疗提供了方便。     

颅内自膨胀支架结合弹簧圈治疗脑动脉瘤

目的　报道采用自膨胀颅内专用支架 (Neuroform支架 )结合弹簧圈栓塞治疗颅内宽颈动脉瘤 ,初步探讨该支架的特点、短期疗效及应用前景。方法　采用Neuroform支架结合弹簧圈栓塞治疗 32例 34枚颅内宽颈动脉瘤。颈内动脉海绵窦段 3例 ,眼动脉 3例 ,后交通动脉 8例 ,前交通动脉 3例 ,大脑中动脉分叉部 5例 ,椎动脉 6例 ,基底动脉顶端 1例 ,基底动脉干 2例 ,大脑前动脉A3段 1例 ,多发动脉瘤 2例。通过Renegade微导管释放Neuroform支架覆盖动脉瘤瘤颈 ,预先将另一微导管置入动脉瘤腔或将微导管通过支架网孔以弹簧圈栓塞动脉瘤。结果　 31例 34个支架成功到位释放 ,1例基底动脉顶端动脉瘤因支架无法通过狭窄的大脑后动脉而改用BX支架。 3例 1次各置入 2枚支架。 2 4例致密栓塞 ,6例瘤颈残留 ,2例部分栓塞。 1例术中发生支架内血栓 ,死亡 1例 ,其余患者均恢复良好出院。临床随访 30例 ,随访期 1～ 6个月 ,平均 4 .7个月 ,无再出血及血栓栓塞症状发生。 1 1例术后 3个月血管造影随访 :7例致密栓塞的动脉瘤均未显影 ;4例瘤颈残留者 ,2例无变化 ;2例原有瘤颈残留未再显影。结论　Neuroform支架技术上容易操控 ,顺应性好 ,安全性高 ,可以到达颅内较远端的血管 ,大大扩展了支架技术治疗颅内血管病变的应用范围 ,近期     

不同介入栓塞技术对前交通动脉瘤破裂患者认知功能的影响

目的 探讨不同介入栓塞技术对前交通动脉瘤破裂患者认知功能的影响.方法 随访收集2012年1月至2014年12月收治的前交通动脉瘤破裂患者共108例,其中经单纯弹簧圈栓塞64例,球囊辅助弹簧圈栓塞18例,支架辅助弹簧圈栓塞26例,对照组为健康人30例.根据蒙特利尔认知评估量表(MoCA)评分,分别于介入栓塞术前、术后1周和术后3个月测试研究对象认知功能.结果 术前前交通动脉瘤破裂患者认知功能障碍发生率高于对照组(P＜0.05);术后1周认知功能障碍发生率及严重程度较术前增高(P＜0.05),支架辅助弹簧圈栓塞患者认知功能障碍程度明显高于单纯弹簧圈栓塞和球囊辅助弹簧圈栓塞患者(P＜0.05),且影响更为持久(P＜0.05).结论 不同介入栓塞技术对前交通动脉瘤破裂患者认知功能均有影响,而支架辅助弹簧圈栓塞治疗对患者认知功能的影响更显著.     

Stress MR imaging for evaluation of popliteal artery entrapment

The popliteal artery entrapment (PAE) syndrome has been recognized as a cause of arterial occlusion in young people. It is the result of an anomaly of the relationship between the popliteal artery and the gastrocnemius muscle. Eight young healthy volunteers (16 legs) and six patients (10 legs) with suspected PAE underwent magnetic resonance (MR) imaging. Gradient-echo images were obtained in axial planes with the leg at rest and during active plantar flexion against resistance. Imaging at rest allowed identification of PAE signs in only one leg, which had an anomalous medial course of the popliteal artery. In the other cases, only the stress technique was able to show signal loss in the popliteal artery due to muscular compression (two legs) or the presence of accessory muscle slip around the vessel (two legs), as confirmed at surgery. MR imaging is therefore a useful technique for the diagnosis of PAE because of its capability of combining information obtainable with other modalities.     

MR imaging of muscle and tender points in fibromyalgia

Fibromyalgia is a syndrome manifested by chronic, diffuse muscu-loskeletal aching and soreness, palpable muscle tender points, and other symptoms. Standardized clinical diagnostic criteria have recently been developed. Skeletal muscle has been postulated as the end organ in this disease. Biochemical, histologic, electromyographic, and conventional radiographic studies have demonstrated no definitive abnormality. This study sought to establish whether magnetic resonance (MR) imaging could demonstrate any abnormality in these patients. Eighteen patients were entered in the study, 14 of whom were able to complete their examinations. T1 -weighted, T2-weighted, gradient-echo, and STIR (short-tau inversion-recovery) sequences were performed in all patients, with selected patients examined with T1weighted, gadopentetate dimeglu-mine-enhanced sequences. The trapezius and suboccipital regions were imaged in patients who, clinically, had active fibro-myalgia. No abnormalities could be detected. The authors conclude that the conventional MR imaging used in this study was unable to depict any primary skeletal muscle abnormality in fibromyalgia.     

Uterine contractions: Possible diagnostic pitfall at MR imaging

A total of 206 nongravid patients with various gynecologic problems underwent pelvic magnetic resonance (MR) examinations that included both sagittal T2-weighted and contrast agent–enhanced T1-weighted images. MR images were retrospectively reviewed to identify changes in endometrial configuration on serial images obtained during the same MR examination. In 20 MR examinations (all in women of reproductive age), endometrial distortion due to myometrial bulging was noted on T2-weighted or contrast-enhanced T1-weighted images. It was absent on other MR images obtained at different times. Myometrial bulging exhibited low signal intensity in 18 examinations. The finding resembled adenomyosis or leiomyoma on T2-weighted or contrast-enhanced T1-weighted images. These results evidence the presence of transient myometrial bulging and transient low-intensity myometrium in the nongravid uterus. This phenomenon is thought to represent uterine contraction. Clinicians should be aware of the potential presence of transient low-signal-intensity myometrial bulging that could present diagnostic problems in the normal uterus.     

Controversies in cervical spine imaging in trauma patients

No area of emergency radiology has generated as much discussion in recent years as the subject of cervical spine imaging for trauma patients. This review will be in three parts. The first will examine the indications for cervical imaging and will focus on those factors that make patients at high risk or low risk for cervical injury. The second part will discuss the merits of radiography and computed tomography as the main screening diagnostic examination. In addition to the roles of each modality in the evaluation process, such factors as efficacy of diagnosis, time (duration) of study, and cost will be discussed. Finally, the third part will explore the methods currently employed to clear the cervical spine in comatose patients.Presented at the Annual Meeting of the American Society of Emergency Radiology, Las Vegas, Nevada, 22–25 October, 2003     

Brodie Abscess: MR imaging appearance in 10 patients

The magnetic resonance (MR) imaging features of Brodie abscess have not yet been fully evaluated. Ten patients with Brodie abscess, eight of long bone and two of vertebra, were studied with MR imaging. Long bone abscess had a characteristic “target” appearance with four layers: (a) a center with low signal intensity on T1-weighted images and high signal intensity on T2-weighted and STIR (short-inversion-time inversion recovery) images, (b) an inner ring isointense to muscle on T1-weighted images and with high signal intensity on T2-weighted and STIR images, (c) an outer ring hypoin-tense on all images, and (d) a peripheral halo hypointense on T1-weighted images. In six of eight cases, a soft-tissue mass was found. The two vertebral abscesses had a less specific appearance, with low signal intensity on T1-weighted images and high signal intensity on T2-weighted and STIR images. Only the peripheral halo was clearly identified in both cases.     

Dynamic contrast-enhanced MR imaging assessment of vascularized free fibular grafts

Magnetic resonance (MR) imaging may be a noninvasive method for assessing perfusion of vascularized bone grafts placed for treatment of avascular necrosis. One proximal femur of seven beagles was devascularized, with insertion of a vascularized fibular graft. MR imaging at 1 week (seven dogs) and 6 weeks (five dogs) after surgery included pre- and postcontrast spin-echo sequences, unenhanced twodimensional time-of-flight (TOF) vascular imaging, and dynamic gradient-echo imaging during infusion of gadolinium. Relative signal intensity values of selected regions obtained from the dynamic gradientecho images were plotted as percent enhancement versus time. In the operated hip, MR imaging did not show enhancement in six of seven femoral heads and greater trochanters at 1 week after surgery, with similar results after 6 weeks. MR imaging of fibular grafts 6 weeks after surgery showed an initial rapid increase in enhancement and a subsequent slower increase in five of five dogs, although no enhancement was seen in six of seven dogs at 1 week. These findings contrasted with a rapid initial increase in enhancement followed by slow decline in non-operated hips. Two-dimensional TOP imaging did not show the vascular pedicle of the graft in any dog. Findings of radionuclide bone scanning performed 1 week after surgery were consistent with devascularization of the operated femur and fibular graft. However, tetracycline distribution and histologic findings confirmed the viability of five of five grafts within the devascularized femurs 6 weeks after surgery. Thus, dynamic contrast-enhanced MR imaging at 6 weeks after surgery is valuable for assessing vascular bone graft perfusion, while similar imaging at 1 week may suggest otherwise.     

Right-side aortic arch with aneurysm of aberrant left subclavian artery: MR imaging appearance.

Reports of aneurysms of the subclavian artery in both normal and anomalous aortic arches have been rare. The authors describe a patient with a right-side aortic arch and an aneurysm of the aberrant left subclavian artery, which, to the authors' knowledge, is a previously unreported association. At presentation, the aneurysm appeared as a calcified left superior mediastinal mass. Magnetic resonance imaging enabled preoperative diagnosis and guided surgical planning.     

Adrenal tissue characterization with 0.5-T MR imaging: Value of T2*-weighted images

The authors investigated the value of magnetic resonance (MR) imaging at 0.5 T for distinguishing adrenal adenomas from adrenal metastases. The series included 23 adrenal adenomas (18 nonhyperfunctioning, five hyperfunctioning) and 23 adrenal metastases from various organs. Adrenal tumor–liver signal intensity ratios on T1-, T2-, and T2*-weighted images were calculated for adrenal tissue characterization. Adrenal adenomas were more precisely distinguished from adrenal metastases on T2*-weighted images (21 of 23, 91%) than on T2-weighted images (15 of 23, 65%). T1-weighted images were not useful for this distinction. In conclusion, T2*-weighted images were better than routine T2-weighted images for distinguishing adrenal adenomas from adrenal metastases. It can be postulated that the total signal intensity of adrenal adenomas, which contain some fat components, decreased on T2*-weighted images because of an out-of-phase effect.     

MR angiography of congenital heart disease: Value of segmented two-dimensional inflow technique and maximum-intensity-projection display

Magnetic resonance (MR) angiography of the cardiovascular system was evaluated in 41 patients with congenital heart disease by using a two-dimensional (2D) inflow technique based on a magnetization-prepared gradient-echo pulse sequence with segmented k-space data acquisition and electrocardiographic gating at 0.5 T. Inversion and saturation prepulses were used to suppress stationary tissue and enhance intravascular signal. Presaturation slabs were applied where certain vascular structures had to be suppressed. Sequence parameters were optimized by evaluating signal intensity and contrast characteristics for various flip angles and inversion and saturation delay times. The heart and intrathoracic vasculature were encompassed with 40–50 overlapping sections. Both 2D angiograms and maximum-intensity-projection images were evaluated. Combining data sets acquired in the sagittal and transverse orientations provided the most satisfactory information about the pulmonary arteries. The highest signal-to-noise ratios were obtained with a flip angle of 65° and short prepulse delay times. Two-dimensional MR angiography can provide useful diagnostic information but requires a thorough understanding of in-plane and hemodynamically induced signal intensity changes.