卵圆孔未闭动物模型的制备

目的 探讨采用经皮房间隔穿刺和球囊扩张法制备犬卵圆孔未闭(patent foramen ovale,PFO)动物模型的可行性.方法 采用22只健康成年犬,经皮房间隔卵圆窝穿刺、球囊扩张术制备犬PFO模型,对其中2只犬的卵圆窝穿刺点进行病理学等检查.结果 22只犬均成功进行房间隔卵圆窝穿刺和球囊扩张术,右房造影可见对比剂由右房进入左房,成功建立了犬PFO模型.完成房间隔卵圆窝穿刺及球囊扩张平均用时(25.1±5.1)min,X线曝光时间平均(5.8±1.6)min.穿刺前右心房平均压为(1.9±0.8)mmHg,穿刺后测得左心房平均压为(2.5±0.7)mmHg.对2只犬的心脏大体观察见心包膜完整;房间隔卵圆窝缺损分别为5 mm×6 mm和6 mm×6 mm,缺损周边均见少量淤血,未见血栓附着,余心内膜均完整.结论 经皮穿刺犬的房间隔卵圆窝、球囊扩张方法制备PFO模型可行.     

双侧无铆型房间隔缺损封堵器的实验研究

目的在犬房间隔缺损(ASD)模型上评价双侧无铆型ASD封堵器的疗效、安全性和生物相容性。方法自行设计封堵器是由镍钛合金丝编织成的网状结构,外形呈双盘状,其左房面平整,右房面中间凹陷,中央有与推送杆相接的连接袢,内衬有三层聚酯膜。犬ASD模型建立采用房间隔穿刺结合球囊扩张方法,模拟临床经导管封堵ASD过程,闭合人工制备的ASD。用心脏超声观察封堵器位置及封堵器对右、左房室瓣功能的影响。术后1、2、3、6个月分别处死动物行组织学检查,观察封堵器周围及表面的组织学反应。结果8条犬成功制作ASD模型并封堵,超声显示封堵器位置固定良好,不影响右、左房室瓣功能。各观察时间点肉眼见所有封堵器表面光滑均覆有薄层的新生内膜。3个月后封堵器表面完全内皮化,光镜和电镜检查显示封堵器置入部位周围组织无明显的炎症反应。6个月扫描电镜观察金属丝无腐蚀。HE染色显示肺、肝、脾、肾、胰等组织无血栓栓塞、炎症表现。结论双侧无铆型ASD封堵器操作简便、使用安全及有良好的生物相容性,提示自制的ASD封堵器将可安全地应用于临床。     

经静脉穿刺制备犬室间隔缺损模型的实验研究

目的　经静脉穿刺制备室间隔缺损 (VSD)模型。方法　健康杂种犬 10只 ,体重 15～2 0kg。氯胺酮 (5mg/kg)肌注、戊巴比妥钠 (2 5mg/kg)静脉麻醉。切开右股动脉和右颈内静脉 ,在X线透视下应用房间隔穿刺针穿刺室间隔 ,经穿刺针送入鞘管 ,交换头端弯曲 1.5圈的左房钢丝至左心室 ,沿钢丝送入直径 6～ 8mm长 4 0mm聚乙烯球囊扩张室间隔穿刺孔。送入猪尾造影导管至左心室 ,行左心室造影。结果　 10只犬中 ,8只犬均穿刺成功 ,并建立VSD模型。 8只犬中 ,除 1例穿刺点在室间隔膜部 ,其余穿刺部位均接近于膜周部 ,穿刺点距主动脉瓣和房室瓣环 4～ 16mm不等。左心室造影显示经室间隔的左向右分流。并发完全性右束支传导阻滞 1例。Ⅲ度房室传导阻滞伴室间隔膜部及房室瓣环处撕裂 1例。结论　经导管穿刺室间隔制备VSD模型的方法可行 ,简便 ,经济     

国产房间隔缺损堵塞装置内皮化的实验研究

目的：评价国产房间隔缺损(ASD)堵塞装置的内皮化。方法：选用乳猪6头(平均体重7．5kg)，利用穿刺针和Rashkind球囊房隔造口术，建立大小不等ASD动物模型；选择适当大小的国产ASD堵塞装置进行封堵；术后1、3和6个月分别将小猪处死(每次2只)，取堵塞装置行扫描电镜检查。结果：术后1个月，装置表面被胶原纤维所覆盖，装置边缘见散在内皮细胞；术后3个月，装置表面大部分被内皮细胞所覆盖，伞尖表面光滑，无内皮细胞覆盖；术后6个月，装置表面完全被内皮细胞所覆盖，伞尖表面光滑并有内皮细胞上爬。结论：国产ASD堵塞装置置入动物体内3个月已大部分内皮化，6个月时已完全内皮化。     

巨大房间隔缺损介入性封堵术23例临床报告

目的 :评价AGAAmplatzer闭合器介入性封堵巨大房间隔缺损 (ASD)的疗效。材料和方法 :2 3例住院患者 ,男10例 ,女 13例。年龄 5～ 49岁 ,平均 33 5岁。体重 17～ 88kg ,平均 6 0 4kg。ASD病理分型 :中央型 2 2例 ,中央偏下型 1例 ,均为单一ASD。ASD直径 (球囊伸长直径 ) 2 8～ 3 6cm。应用AGAAmplatzer闭合器 ( 2 8～ 40型号 ) ,在X线和食道超声 (TEE)监测下闭合ASD。其闭合器型号与球囊伸长直径相等或大于 2～ 4mm。结果 :2 3例ASD中 ,2 1例闭合成功 ,成功率 92 %。 2例闭合器脱落 ,无其它并发症发生。结论 :AGAAmplatzer闭合器闭合大型ASD是安全的 ,有效的 ;但在操作中注意防止闭合器脱落并发症发生。     

房间隔缺损堵闭术Amplatzer封堵器的选择

目的　分析和总结房间隔缺损(ASD)堵闭术中Amplatzer封堵器的选择方法。方法　30例ASD患者,术前经胸超声心动图(TTE)或食管超声心动图(TEE)检查明确ASD大小及周围结构,初步估计封堵器型号。术中再次依据TTE、水球囊测量(34mm以上ASD除外)确定合适的Amplatzer伞进行ASD封堵,并依靠TTE明确封堵效果。结果　TTE显示30mm以下的ASD直径12～2 8(18.4 1±6 .16 )mm ,水球囊测量值为14～30 (2 2 .84±6 .19)mm ,选择封堵伞直径为14～30 (2 4 .6 9±6 .99)mm ,TTE显示30mm以上ASD有12例患者,其中选择4 0mm封堵器6例,4 2mm封堵器1例。30例ASD患者,2 8例封堵器置入获得成功,1例双孔ASD患者,一伞堵双孔,术后未见分流,1例巨大ASD ,封堵失败,1例术中封堵器脱落,转胸外科手术,其余患者未发生任何并发症。结论　应用TTE可较准确的独立估测ASD直径的球囊测量值,ASD直径的水球囊测量值应作为TTE示30mm以下ASD选择封堵器的“金标准”;30mm以上ASD患者可直接用TTE测量值指导封堵器选择。TEE可作为多孔ASD及TTE显示不清ASD患者的重要补充检查     

介入造影定位法制作比格犬卵圆孔未闭模型

目的 介绍一种用于制作比格犬卵圆孔未闭(PFO)模型的介入造影定位穿刺方法.方法 15只健康比格犬通过介入造影定位法制作PFO模型.全身麻醉下穿刺右股静脉,在右前斜30°X线投照角度下,于上腔静脉边推对比剂边回撤导管至右房底部作造影,结合改良有心房造影穿刺(Inoue法)定位法作房间隔穿刺,用14F扩张鞘管扩张房间隔,制作犬PFO模型.结果 与犬房间隔穿刺相关生理与解剖:静息心率快,左右心房内径小,伴有奇静脉开放,下腔静脉在右心房开口位置高,下腔静脉长轴与其入右心房口处均有明显成角,且与房间隔平面成角大.15只比格犬右股静脉穿刺成功率为100％;14只犬房间隔穿刺成功,且均制成PFO模型,1只犬穿破心包放弃进一步操作,成功率为93.3％(14/15);PFO模型制成后即刻超声测量显示,PFO大小为2.5～4.1(3.2±0.7)mm.结论 介入造影定位法制作比格犬PFO模型,操作简便、安全,成功率高.     

封堵器治疗房间隔缺损和动脉导管未闭的疗效评价

目的研究非常规方法选择Amplatzer治疗房间隔缺损及动脉导管未闭的可行性。方法14例II孔型ASD和1例动脉导管未闭,经术中常规右心导管检查,测量右室与肺动脉压力,经导引钢丝导入球囊导管测AS最大伸展直径,用体表经胸超声心动图(TTE)或经食管超声(TEE)测量房间隔直径及确定ASD的位置及大小,根据球囊最大伸展直径选择应用等于或大于其1～2mm型号的国产ASD和PDA封堵器。结果15例患者应用15个封堵器均获成功,成功率为100%,无并发症,亦无残余分流。结论国产封堵器具有操作简便、效果可靠、成功率高、安全等优点,应用封堵器封堵ASD和PDA是安全有效的。     

X线导向下逆行腘动脉穿刺植入支架治疗股浅动脉闭塞症九例

目的 探讨X线导向下逆行腘动脉穿刺在股浅动脉闭塞介入治疗中的应用价值.方法 对9例股浅动脉长段闭塞患者采用经股动脉入路顺行开通受阻,改用X线导向下逆行腘动脉穿刺技术成功建立通路后,对闭塞段行球囊扩张及支架植入治疗.结果 9例患者腘动脉穿刺技术均获成功,闭塞段股动脉均获开通,间歇性跛行症状消失,未出现相邻神经、血管损伤...     

犬肺栓塞缺血-再灌注损伤模型的实验研究

目的 建立一种良好的适合进行影像学实验研究的肺栓塞缺血-再灌注损伤动物模型.方法 健康杂种犬20只.采用Seldinger技术穿刺右颈内静脉,置鞘,经鞘置入Swan-Ganz导管,用其球囊栓塞犬的右肺下叶动脉4 h,然后再撤除球囊,使血流再灌注4 h,制成肺栓塞缺血-再灌注损伤模型.在缺血前、缺血4 h和再灌注4 h 3个时间点进行肺部CT扫描.最后处死犬,把双下叶肺组织送检病理和电镜检查.结果 成功制作20只犬的闭胸式活体肺栓塞缺血-再灌注损伤模型,CT、病理和电镜扫描显示均符合肺栓塞缺血-再灌注损伤的变化,即渗透性肺水肿.结论 犬的闭胸式活体肺栓塞缺血-再灌注损伤模型可真实模拟肺栓塞缺血-再灌注损伤的病理生理过程,是一种良好的适合进行影像学实验研究的动物模型.     

先天性心房间隔缺损的介入治疗

目的：探讨应用Amplatzer封堵器介入治疗房间隔缺损(ASD)的方法及疗效。方法：20例ASD患者，年龄4—39岁，术前行心脏超声检查确诊。选择封堵器直径为10～30mm，在透视下经导管植入Amplatzer封堵器封堵ASD。结果：20例ASD，封堵成功，术中无并发症发生。结论：经导管植入Amplatzer封堵器介入治疗ASD是一种安全有效的方法，值得临床推广应用。     

Uterine artery embolization: reduced radiation with refined technique

PURPOSE: To determine the estimated absorbed ovarian dose (EAOD) and absorbed skin dose (ASD) that occurs during uterine artery embolization (UAE) using pulsed fluoroscopy and a refined procedure protocol. MATERIALS AND METHODS: The absorbed dose was measured in 20 patients who underwent UAE procedures. Radiation was limited by using low frequency pulsed fluoroscopy, bilateral catheter technique with simultaneous injections for embolization as well as pre-and postembolization exposures and focus on limitation of magnified and oblique fluoroscopy. Lithium fluoride dosimeters were placed both in the posterior vaginal fornix and on the skin at the beam entrance site. The vaginal dose was used to approximate the EAOD. Fluoroscopy time and exposures were recorded. The mean values for all patients were calculated and compared to our previous results obtained with conventional fluoroscopy and to threshold doses for the induction of deterministic skin injury. RESULTS: Mean fluoroscopy time was 10.95 min. (range 6-21.3 min.) and the mean number of angiographic exposures was 20.9 (range 14-53). The mean EAOD was 9.5 cGy (range 2.21-23.21 cGy) and the mean ASD was 47.69 cGy (range 10.83-110.14 cGy). This compares to previous results with non-pulsed fluoroscopy of an EAOD of 22.34 cGy (range 4.25-65.08 cGy) and an ASD of 162.32 cGy (range 66.01-303.89 cGy) as well as threshold doses for induction of deterministic radiation injury to the skin (400-500 cGy). CONCLUSION: When pulsed fluoroscopy is used with emphasis on dose reduction techniques, the EAOD and ASD can be substantially reduced to less than 1/2 (P = .017) and 1/3 (P < .0001) when compared to UAE performed with nonpulsed fluoroscopy. These radiation reduction tools should therefore be applied whenever possible.     

Balloon sizing and transcatheter closure of acute atrial septal defects guided by magnetic resonance fluoroscopy: assessment and validation in a large animal model

PURPOSE: To quantitatively assess atrial septal defects (ASDs) with small shunts using MRI followed by transcatheter closure monitored by MR fluoroscopy. MATERIALS AND METHODS: Acute ASDs were created in 14 pigs under x-ray fluoroscopy. Six animals were studied in order to select MR-compatible delivery systems and imaging strategies. ASDs in eight animals were examined with balloon sizing under MR fluoroscopy, flow measurements, and contrast media injections, after which transcatheter closure was performed under MR fluoroscopy. The delivery system was assembled from commercially available materials. RESULTS: The ratio of pulmonary to systemic flow (Qp/Qs) was reduced from 1.23 +/- 0.15 before ASD closure to 1.07 +/- 0.11 after ASD closure (P < 0.001). In two out of eight animals Qp/Qs was close to 1.0 before closure despite the presence of defects >15 mm. The ASDs were measurable with MR balloon sizing in all of the animals. Balloon sizing was identical with MR (16.9 +/- 2.3 mm) and x-ray fluoroscopy (17.1 +/- 1.3 mm). The in-house-assembled delivery system allowed successful placement of closure devices under MR guidance. CONCLUSION: Assessment and closure of small shunts with MR fluoroscopy is feasible. A barrier to the rapid implementation of transcatheter closure in patients is uncertainty about the MR safety of guidewires and device delivery systems.     

Pancreatic pseudocysts drained through a percutaneous transgastric approach

We describe a new method for the percutaneous drainage of pancreatic pseudocysts using a transgastric approach. We used this technique in three dogs and six patients for whom no other "safe" access route was available. The procedures were performed under US guidance alone or with US combined with fluoroscopy. No complications were observed.     

Small bowel biopsy by coaxial catheter. A simple, rapid technique.

A new small intestinal biopsy technique was developed and evaluated: it involves the rapid replacement of a simple duodenal tube using a controllable spring guide and fluoroscopy. A suction biopsy catheter was then passed coaxially through the tube as often as needed for sampling, after which other diagnostic studies were done with the same intubation. In clinical trials totaling 31 biopsies in 15 adult patients, the method proved safe and effective. Currently, the time required to intubate the ligament of Treitz and obtain two biopsies is usually less than 15 minutes.     

A nonoperative technique for establishment of a gastrostomy in the dog

Gastrostomies have been performed nonoperatively under local anaesthesia using a simultaneous percutaneous and endoscopic approach. This technique has been modified to be done under fluoroscopy without the need for endoscopy. The technique and results in five dogs are described.     

A hybrid computerized fluoroscopy technique for noninvasive cardiovascular imaging.

The excellent linearity of digital image storage and retrieval permits hybrid analog-digital subtraction to extend the spatial resolution of two previously developed algorithms which employed entirely digital apparatus. A low resolution, time-integrated preinjection digital mask image is reconverted to analog form and subtracted from live analog video images of iodine administered by peripheral intravenous injection to produce a high resolution display of the cardiovascular system with contrast ten times greater than conventional fluoroscopy. Preliminary studies in dogs are compared with images obtained with our digital subtraction algorithms.     

Trial of finger contamination reduction of the operator in nerve block treatment: comparison of over- and under-table systems

Fluoroscopy-guided intervention of the lumbar spine, such as nerve block, plays an important role in the management of disc hernia patients. However, irradiation of operators' fingers remains a problem even with careful collimation and operation, especially when performed by non-radiologists. We compared the irradiation doses of under-table and over-table fluoroscopy systems, and we discuss the most advantageous method of reducing irradiation. The effectiveness and conditions of use of lead protection gloves were also evaluated. Skin dose was monitored using polymethyl methacrylate (PMMA) and an electronic dose meter. The skin doses of over- and under-table fluoroscopy were compared using C-arm fluoroscopy. Finger irradiation dose with 0.03 mmPb protection gloves was also measured. The under-table method reduced skin dose by 95% compared with the over-table method. Thicker PMMA resulted in a higher rate of irradiation reduction. Protection gloves reduced radiation dose by half, although this reduction was cancelled when automatic brightness control (ABC) was utilized. Under-tube fluoroscopy was superior to over-tube fluoroscopy in reducing irradiation to the fingers.     

Fluoroscopic and arthrographic evaluation of carpal instability

The efficacy of a diagnostic protocol involving videotape fluoroscopy of carpal motion and radiocarpal arthrography was evaluated in patients with wrist pain unexplained by physical examination and conventional radiographs. Videotape fluoroscopy was performed as the first study in 68 consecutive cases and was positive in 44 (66%). Radiocarpal arthrography was performed after videotape fluoroscopy in 39 of the cases (57%), including the 24 in which videotape fluoroscopy was normal and 15 others in which further information was desired in spite of positive videotape fluoroscopy. The addition of radiocarpal arthrography to videotape fluoroscopy increased the diagnostic yield to 52 (76%) of the 68 cases and excluded significant anatomic or dynamic abnormality in the others. The diagnosis was proven surgically in 25 cases. This protocol was efficacious for ligament tears of the proximal carpal row, triangular fibrocartilage tears, and proximal and midcarpal instability. Videotape fluoroscopy should be the primary method of evaluating patients with unexplained wrist pain, and arthrography should be done in those cases in which fluoroscopy is either normal or does not fully explain physical findings.