主动脉MSCTA对比剂注射方案优化的探讨

目的比较相同碘浓度和注射速率、不同对比剂注射方案对主动脉多层螺旋CT血管成像（MSCTA）应用效果的影响。方法100例可疑主动脉病变患者随机分为A、B两组（n=50）,分别采用不同对比剂注射方案进行主动脉CTA检查：A组注射对比剂100ml,对比剂浓度300mgI／ml,注射速率3ml／s;B组注射对比剂60ml后用40ml生理盐水冲刷,对比剂浓度及注射速率同A组。扫描延迟时间采用自动触发技术。测量升主动脉、胸7（T7）及腰2（L2）水平降主动脉、主动脉分叉处CT值;由两位影像诊断高级职称医师对血管强化程度、重组血管清晰度进行评价。结果两种注射方案在升主动脉、T7及L2水平降主动脉、主动脉分叉处的平均强化程度分别为255HU和240HU,两组间差异不具有统计学意义;两组重组血管清晰度无统计学差异。两侧肾动脉及分支血管清楚显示率为93％。结论应用对比剂60ml注射＋40ml生理盐水冲洗行主动脉MSCTA能满足主动脉检查要求,并减少对比剂用量。     

不同扫描方向对头颈联合CT血管造影图像质量的影响

目的通过改变头颈联合CTA成像的扫描方向避免较重的颅内静脉回流伪影及锁骨下静脉注射伪影,从而获得高质量的诊断图像。方法选择在我院接受头颈联合CTA检查的患者200例,随机分成A、B两组（各100例）,分别进行头向足方向及足向头方向扫描,其他扫描参数相同。对图像质量进行评分,记录升主动脉、颈总动脉、基底动脉CT值及对比剂注射侧锁骨下静脉CT值和升主动脉中心部噪声值,并进行统计学分析。结果①A组图像质量明显优于B组,差异有统计学意义（U=7.40,P〈0.001）。②两组基底动脉、颈总动脉、升主动脉CT值比较,差异无统计学意义（P均〉0.05）。③两组注射侧锁骨下静脉CT值差异有统计学意义（U=22.91,P〈0.001）。④两组升主动脉中心部噪声值比较,差异有统计学意义（U=2.61,P〈0.05）。结论头颈联合CTA成像,选用头向足方向扫描可以有效避免较重的颅内静脉回流伪影及注射侧锁骨下静脉残留对比剂的伪影,同时能够得到强化均匀的高质量诊断图像。     

改良Bentall手术在StanfordA3型主动脉夹层治疗中的应用

目的总结改良主动脉根部置换手术（改良Bentall手术）j在Stanford A3型主动脉夹层（aortic dissection,AD）手术中的应用经验及其效果。方法2004年1月至2013年6月南京医科大学附属南京医院共对54例Stan-fbrd A3型主动脉夹层（根据孙立忠的主动脉夹层细化分型原则）患者施行了主动脉根部置换手术,其中男41例、女13例,年龄21～73岁;Bentall手术12例,Bentall＋右半弓置换手术14例,Bentall＋全弓置换＋支架象鼻手术28例。根据手术方式不同,将54例患者分为两组,A组：36例,主动脉根部置换施行传统Bentall手术;B组：18例,主动脉根部置换施行改良Bentall手术,即在传统Bentall手术的基础上,对窦部直径小于45mm、冠状动脉开口移位不明显的患者采用“城门洞”法冠状动脉开口吻合技术。比较两组患者的术后转归和并发症发生情况。结果两组患者的年龄、性别比率差异无统计学意义。A组窦部直径明显大于B组[（52．11±3．62）mm vs．（40．72±2．67）mm,P=0.000],差异有统计学意义;两组患者的手术时间、体外循环时间、术中深低温停循环时间、术后胸腔引流量和住ICU时间差异均无统计学意义（P〉0．05）。术后死亡4例,其中A组2例,B组2例,两组住院死亡率差异无统计学意义[5．56％（2／36）VS．11．11％（2／18）,P=0．462];2例因无法控制的渗血、1例因腹主动脉夹层动脉瘤破裂、1例因急性肺梗塞死亡。随访48例,随访时间3个月,失访2例。随访期间有48例患者复查CTA（computed tomography angiography）,主动脉根部未见假性动脉瘤形成,冠状动脉开口未见动脉瘤或狭窄。结论主动脉夹层累及主动脉根部时需要行主动脉根部置换手术,对于窦部直径小于45mm、冠状动脉开口移位不明显的患者,可以施行改良Bentall手术,即“城门洞”法冠状动脉开口吻合技术,其技术简?     

低管电压扫描条件下个体化对比剂用量方案在冠状动脉CTA中的应用

目的探讨冠状动脉CTA中以体质量指数(BMI)与体表面积(Suf)作为个体化分类标准,联合100kV低管电压扫描,降低对比剂用量、提高造影效率和图像质量的价值。方法入组患者17.0≤BMI26.5,分为120kV组(A组)与100kV组(B组),各100例。A组扫描管电压120kV,管电流600mA;对比剂0.8~1.0ml/kg(总量约65ml),生理盐水50ml,注射流率均为5.0ml/s。A组检查完毕后采用线性回归分析对比剂用量与BMI、Suf关系,制成量化速查表。B组扫描管电压100kV,管电流600mA;对比剂根据上述速查表采用35~65ml,生理盐水30~50ml(对比剂总量×80%),注射流率均为5.0ml/s。结果两组对比剂用量、主动脉强化值、左心室强化值、图像噪声、辐射剂量指数、有效剂量差异均有统计学意义(P均0.05),B组较A组对比剂用量下降28.16%、主动脉强化值提高21.58%;辐射剂量指数下降39.54%、有效剂量下降40.83%、噪声值升高27.15%。两组图像质量评分B组优于A组(P0.01)。结论以BMI、Suf作为个体化分类标准,可降低检查中对比剂用量、提高造影效率;结合100kV低管电压扫描,能在显著降低辐射剂量的同时改善图像质量。     

急性主动脉夹层累及根部的外科治疗

目的探讨Stanford A型急性主动脉夹层累及根部的手术治疗策略。方法上海交通大学医学院附属仁济医院自2005年1月至2010年12月,共62例Stanford A型急性主动脉夹层累及根部的患者接受手术治疗。根据对夹层近心端采用的不同手术处理方法分为3组,A组:28例,男20例、女8例,年龄(45.2±15.6)岁;行主动脉瓣交界悬吊+升主动脉置换术;B组:10例,男7例、女3例,年龄(44.6±14.9)岁;行部分窦部成形+升主动脉置换术;C组:24例,男17例、女7例,年龄(46.2±15.6)岁;行Bentall手术。比较分析3组患者的临床效果。结果围术期死亡6例,病死率为9.67%(6/62)。共随访54例,随访(27.3±15.7)个月。随访期间死亡2例,1例死亡原因不明,1例死于肺癌。A组1例患者术后6个月复查CT显示主动脉窦部假性动脉瘤。C组体外循环时间、主动脉阻断时间明显较A组和B组长[(274±97)min vs.(194±65)min、(210±77)min,t=22.482,30.419,P=0.002,0.122;(150±56)min vs.(97±33)min、(105±46)min,t=12.630,17.089,P=0.000,0.034]。3组患者的住院死亡率(t=1.352,P=0.516)及围术期二次开胸、急性肾损伤、神经系统并发症发生情况差异无统计学意义(t=0.855,0.342,2.281;P=0.652,0.863,0.320)。结论针对急性主动脉夹层病变累及根部的手术治疗可以采用主动脉瓣交界悬吊+升主动脉置换术、部分窦部成形+升主动脉置换术和Bentall手术等方法,并各有其优缺点。掌握每种方法的手术指征,灵活运用,可以获得满意的临床效果。     

利用“多余”冠状动脉纽片作主动脉根部成形在大动脉转位术中的应用

目的总结大动脉转位术(ASO)中利用"多余"的冠状动脉纽片作新主动脉根部成形的临床经验,探讨保持主动脉瓣窦的解剖形态对改善术后冠状动脉血流的临床意义。方法选取2003年1月至2009年6月,我院收治的室间隔缺损型大血管错位和Taussig-Bing畸形患者110例,手术年龄为出生2d～2岁,平均年龄91.1d;体重1.79～9.50kg,平均体重4.70kg。根据不同的外科处理技术,将患者分为两组,A组:78例,术中采用多余的冠状动脉纽片作新的主动脉根部成形,减小新主动脉根部近心端开口的直径;B组:32例,术中剪除多余的冠状动脉纽片,主动脉吻合口近心端与远心端直径不匹配。采用logistic逐步回归筛选结果中影响住院死亡的危险因素。结果术后早期死亡12例,总病死率为10.9%(12/110),A组病死率明显低于B组[6.4%(5/78)vs.21.9%(7/32),P=0.019]。随访72例,随访时间为术后3个月～5年。后期死亡3例,A组1例,B组2例;5例患者再次手术。单因素logistic回归分析结果显示:影响术后早期死亡的危险因子包括Taussig-Bing畸形(χ2=4.011,P=0.046)、合并主动脉弓病变(χ2=4.437,P=0.036)、单支冠状动脉(χ2=5.071,P=0.025)和B组患者(χ2=5.584,P=0.019)。多因素logistic回归分析结果显示:合并主动脉弓病变(χ2=5.681,P=0.010)和B组患者(χ2=3.987,P=0.047)是构成影响术后早期死亡的独立危险因子。结论利用"多余"的冠状动脉纽片作新的主动脉根部成形能够较好地保持新主动脉瓣窦形态,而主动脉根部的特殊解剖形态与冠状动脉灌注有重要的关系,手术病死率降低可能与术后冠状动脉灌注得到改善有关。     

Stanford B型主动脉夹层腔内支架修复术后再发逆撕型A型主动脉夹层的外科治疗

目的 探讨Stanford B型主动脉夹层腔内支架修复术后再发逆撕型A型主动脉夹层的原因及其外科治疗的临床疗效。方法 回顾性分析2014年3月—2018年8月既往行腔内修复的Stanford B型主动脉夹层患者因再发逆撕型A型主动脉夹层于海军军医大学附属长海医院行外科手术患者的临床资料。出院患者均常规门诊复查和电话随访。结果 共纳入16例患者，其中男13例、女3例，年龄（49.1±12.2）岁。再发A型夹层时症状为胸痛12例，头痛和意识障碍各1例，无症状2例。16患者均接受升主动脉置换，全弓置换加支架象鼻植入术。主动脉根部行Bentall手术2例，行根部成形术10例，行主动脉瓣置换术1例。术中发现夹层破口明确位于近端金属裸支架周围共10例，另外6例破口位于升主动脉前侧壁。术中体外循环时间为（152.2±29.4）min，主动脉阻断时间为（93.6±27.8）min，选择性脑灌注时间为（29.8±8.3）min。住院期间及术后30 d内无死亡。术后随访32～85(57.4±18.3)个月。随访期间均存活，1例于术后3年因腹主动脉夹层再次行腔内支架植入术。结论 采用全弓置换合并支架象鼻技术...     

妊娠晚期及产褥期合并急性主动脉夹层的临床治疗策略

目的探讨妊娠晚期(孕晚期)及产褥期合并急性主动脉夹层的临床特点、治疗策略及治疗效果。方法回顾性分析2012年8月至2017年6月间上海长海医院7例妊娠合并急性主动脉夹层患者的临床资料。5例妊娠晚期、2例产褥期,Stanford A型主动脉夹层6例(85.7%)、B型1例(14.3%),年龄26~34(30.8±3.1)岁。患者发病时间为孕28周至产后18 d,其中5例孕妇发病时间平均(31.8±2.63)周。A型夹层患者心脏超声显示升主动脉最宽内径4.2~5.7(4.7±0.6)cm,2例合并主动脉窦瘤,3例为马方综合征(42.8%)。A型夹层患者主动脉处理方式为:Bentall手术1例,Bentall+Sun’s手术2例,升主动脉置换+Sun’s手术+冠状动脉旁路移植术1例,主动脉根部成形+升主动脉置换+Sun’s手术2例。B型夹层患者先行剖宫产后再行胸主动脉腔内修复术(thoracic endovascular aortic repair,TEVAR)。结果主动脉阻断时间51~129(85.5±22.9)min,体外循环时间75~196(159.0±44.0)min,中低温停循环+选择性脑灌注时间为20~30(23.8±3.5)min。所有母体及胎儿均存活,其中先行主动脉修复而后期行剖宫产的1例胎儿经诊断为脑瘫。孕妇及新生儿随访9个月至4年,随访期内除脑瘫胎儿外其余婴幼儿均发育生长良好;7例孕妇均恢复良好;早期先行主动脉修复的孕妇(仅1例),在后期剖宫产时发现乙状结肠破裂同期行乙状结肠造瘘术治疗;另1例A型夹层的产妇,出院2年后经诊断为胡桃夹综合征。结论妊娠晚期合并主动脉夹层多为A型夹层患者,马方综合征是妊娠合并急性主动脉夹层患者的高危因素。尽早手术并根据主动脉夹层类型及胎龄选择相应的治疗策略,妊娠晚期及产褥期合并主动脉夹层患者可获得良好的母儿结局。     

再次及多次主动脉瘤手术的临床分析

目的：总结13例共27次主动脉瘤手术的经验。方法：全组13例中男8例,女5例,2次手术者12例,3次手术1例,再次手术距前次手术平均50个月（22d-233个月）,首次手术分别是：主动脉根部置换7例,慢性B型夹层行胸降主动脉人工血管置换3例,肾动脉下方腹主动脉瘤切除人工血管置换1例,急性A型夹层行主动脉瓣及升主动脉成形,川崎病行升主动脉人工血管置换和左冠状动脉前降支成形各1例,再次手术分别是因残余夹层扩大行全弓置换加ElephantTrunk1例,胸降主动脉置换2例,2例再发弓部夹层,1例行根部置换＋部分弓部置换,1例行升弓部置换;2例胸降主动脉瘤,1例胸腹主动脉瘤,1例B型夹层,常温阻断下行人工血管置换术,1例根部瘤在中低温体外循环下行根部置换术,川崎病再发无名动脉和弓部动脉瘤行无名动脉及部分弓置换1例,1例A型夹层升主动脉及主动脉瓣成形术后感染性假性动脉瘤形成,1例再发升主动脉瘤行升主动脉置换;1例根部置换再行弓降部置换术后,再发弓部动脉瘤,第3次手术行全弓置换,再手术时采用深低温停循环8例,常温阻断4例,中低温体外循环2例。结果：术后4例出现脑部并发症,1例肝功能异常,均治愈,无住院死亡。随访远期死亡3例,另有2例随访6个月和70个月,现待手术。结论：再次手术以再发或多发动脉瘤（包括主动脉夹层）为最常见原因,其次是残余夹层进一步发展,再次手术一定要积极,以免延误手术时机导致死亡。应根据再次手术的部位选择基本方法,累及弓部需深低温停循环并选择性脑灌注,远弓部和胸,腹主动脉可用常温阻断或股一股转流,如无法游离阻断则需要深低温停循环,累及根部则只需要一般体外循环,大出血和昏迷是再次手术最危险的并发症,尽早建立体外循环,低温和停循环期间的脑灌注可有效预防这类并发症。     

升主动脉置换术或成形术治疗主动脉瓣病变合并的升主动脉瘤样扩张

目的 对比分析主动脉瓣病变合并升主动脉瘤扩张在行主动脉瓣置换术(AVR)的同时施行升主动脉置换术(A组)或成形术(B组)的结果,探讨两种方法的临床效果及适应证.方法 A、B两组术前年龄、性别、心功能分级、主动脉瓣病变、左室射血分数等差异均无统计学意义.A组主动脉直径(49.45±3.96)mm,B组(49.31±3.68)mm,差异亦无统计学意义.行AVR后A组常规置换升主动脉,B组纵行切除部分升主动脉壁,缝合后包裹28～30 mm人工血管.结果 A、B两组术后均无死亡.A组主动脉阻断(71.70±17.13)min、体外循环(110.52±27.51)min,均明显大于B组的(57.13±16.32)min(P=0.025)和(97.31±19.46)min(P=0.004).两组术中及术后输血量、并发症发生率差异无统计学意义.结论 主动脉瓣病变合并升主动脉瘤样扩张,年轻病人主动脉直径≥40 mm时应积极手术处理扩张的升主动脉.升主动脉成形术,同时外包裹人工血管的方法较升主动脉置换术更为简单、安全,但升主动脉壁必须无粥样硬化或溃疡.     

Treatment of type B aortic dissection: endoluminal repair or conventional medical therapy?

OBJECTIVE: To evaluate the mid-term results of endovascular stent-grafting for type B aortic dissection, in comparison with those of standard medical therapy in uncomplicated cases. METHODS: Between January 1999 and 2004, among 56 patients (mean age 59.5+/-11.5 years) with type B aortic dissection, hypotensive medical therapy was the only treatment in 28 uncomplicated cases, (group A), while stent-graft implantation was performed in 28 patients with uncontrolled hypertension, persistent pain or evidence of dissection progression or complication (group B). In 14 cases (50%) the procedure was performed in an acute setting. Stent-grafting procedures were monitored with intraoperative trans-esophageal echocardiography and cine-angiography. CT scan and trans-esophageal echocardiography were performed before hospital discharge, at 6 and 12 months and then yearly. RESULTS: Follow-up (range 1-61 months, average 18.1+/-16.9 months) was 100% complete. In-hospital mortality was 10.7% (three patients, all belonging to Group B; P=0.24). No spinal cord injuries were observed. Early endoleak occurred in one patient (3.5%). Mid-term mortality was lower in Group B, although the difference was not significant (10.7 versus 14.3% in Group A, P=0.71). Follow-up CT scans evidenced complete thrombosis of the false lumen in 75% cases in Group B, 10.7% in Group A (P=0.0001), and an aneurismal dilatation of the descending aorta in 3.5% cases in Group B, 28.5% in Group A (P=0.02). CONCLUSIONS: Although with still considerable early mortality, endovascular stent-graft implantation is an effective option for the treatment of complicated type B aortic dissection. Endovascular treatment achieved a better mid-term fate of the descending thoracic aorta than medical therapy alone, even in patients with worse preoperative conditions.     

The usefulness of dynamic computed tomography scanning in predicting the outcome of acute stroke patients]

The aim of this study was to investigate whether brain dynamic computed tomography (CT) is useful in predicting clinical outcome. Thirty patients suffering from cerebral ischemia in the territory of the middle cerebral artery (MCA) underwent dynamic CT scanning within 6 hours of stroke onset. Regions of interest (ROIs) were placed in the bilateral MCA territories and three parameters, peak value (PV), time to peak (TP), and PV divided by TP, were calculated from time-density curves (TDCs) on ROIs. After conventional treatment using pharmacological agents, the 30-day clinical outcome was evaluated on the Glasgow outcome scale. To investigate the relationship between the disease-to-contralateral side ratio of each parameter's value and 30-day clinical outcome, TDCs were classified into the following four types; type 1, with TP ratio less than 1.1; type 2, with TP ratio ranging from 1.1 to 1.5 and PV/TP ratio more than 0.75; type 3, with TP ratio ranging from 1.1 to 1.5 and PV/TP ratio less than 0.75; and type 4, with TP ratio more than 1.5 and PV/TP ratio less than 0.3. Clinical outcome in patients with type 1 or 2 TDC was better than in patients with type 3 or 4 TDC (p < 0.01, Fisher's exact test). We can conclude that dynamic CT is a useful means for estimating the clinical prognosis of acute stroke patients after conventional treatment. Poor clinical outcome following conventional therapy is expected in patients with type 3 or 4 TDC in contrast to patients with type 1 or 2 TDC.     

急性Stanford B型主动脉壁间血肿的治疗

目的 探讨急性Stanford B型主动脉壁间血肿的治疗方法和预后.方法 总结2001年1月至2008年3月收治的Stanford B型主动脉壁间血肿29例的临床资料.依据以下标准将患者分为三组:(1)有主动脉硬化性穿透性溃疡;(2)血压不易控制;(3)持续胸背部不适.符合上述任何一项的患者入选为腔内治疗组(13例),其余患者归入药物治疗组(16例).腔内治疗组采用降主动脉覆膜支架置入术;药物治疗组只接受降压、止痛等内科保守治疗.结果 本组29例患者均获随访,随访时间6～89个月,平均(19±16)个月,药物治疗组16例患者3例病情进展为夹层予支架治疗,2例突发主动脉破裂而死亡,疾病恶化率为31.25%,死亡率为12.5%;腔内支架治疗组13例患者随访期间未见夹层复发、支架移位及其他并发症.总共置入覆膜支架16个.结论 急性Stanford B型主动脉壁间血肿疾病恶化率高,腔内覆膜支架置入术是积极有效的治疗方法.     

Endovascular stent-graft treatment for diseases of the descending thoracic aorta.

OBJECTIVE: Assessment of endovascular stent-graft treatment for diseases of the descending thoracic aorta as a valid and effective alternative to surgery. METHODS: From March 1999 to August 2000, a total of 16 patients underwent deployment of endovascular stent-grafts in the descending thoracic aorta. Patients were divided into three groups according to the type of lesion. Group A (n=8) included five patients with atherosclerotic aneurysm and three with chronic post-traumatic pseudoaneurysm. Patients with acute post-traumatic pseudoaneurysm (n=3) and type B aortic dissection (n=5) were included in Groups B and C, respectively. All patients underwent 5-mm chest spiral angio-computerized tomography (CT) scan and angiography as preoperative assessment. The deployed stent-graft systems were Talent-Medtronic and Excluder-Gore. RESULTS: A total of 20 stent-grafts were placed. Two patients required deployment of two grafts, while three grafts were juxtaposed in a third patient in order to treat larger lesions. There was no mortality related to the procedure, although one patient (6.2%) died because of multiorgan failure 24h post-operatively. The placement of the graft was successful in all cases except one affected with type B dissection and characterized by a very large intimal flap, which was eventually fenestrated by graft guidewire. Therefore, an optimal sealing of the grafts was achieved in 15 patients. However, in one patient the descending aorta had to be surgically replaced because of the calcified pseudoaneurysm still compressing the trachea and left bronchus. Two patients required a left carotid-subclavian by-pass in order to achieve a sufficient neck for the proximal placement of the graft. No spinal cord injuries were observed. At the follow-up, performed with chest spiral angio-CT scan within 72 h and scheduled at 6 and 12 months and once a year, no stent-graft related complications have been detected. CONCLUSIONS: Endoluminal stent-graft treatment may represent a valid option in well-selected cases of descending thoracic aorta diseases. A longer follow-up in a larger series of patients is desirable to confirm these initial positive results.     

CT检查在腹腔实质器官损伤中的临床价值

目的 探讨腹腔实质器官损伤中CT影像学表现的临床价值.方法 对外伤所致腹部脏器损伤的159例患者行平扫和(或)增强扫描,增强扫描采用动脉期、实质期,肾脏加做延迟期,与行增强扫描复查病例进行对比分析.结果 159例病例中,98例CT诊断为腹腔实质脏器挫裂伤,经手术与临床追踪得到证实,22例为单纯空腔脏器损伤或脊柱、骨盆骨折,39例为阴性,检查阳性率为75.5%(120/159),诊断符合率为98.1%(156/159).结论 CT检查能清楚显示实质脏器内损伤情况、包膜下血肿、腹膜后血肿、腹腔积液量,能对损伤的程度进行分级,正确选择扫描技术在腹部损伤诊断中有重要的临床价值.     

64排螺旋CT前置与后置心电门控 冠状动脉成像比较

目的比较前置心电门控（前门控）与后置心电门控（后门控）64排螺旋CT（64 MDCT）冠状动脉成像的图像质量及放射剂量,探讨前门控对冠心病的临床应用价值。方法48例患者随机分为两组,每组24例,平均心率分别为（61.67±7.29）次/分和（65.83±8.44）次/分,分别进行64 MDCT前、后门控冠状动脉扫描;采用t检验对两种扫描方式的冠状动脉图像质量及有效放射剂量进行统计分析。结果前门控与后门控两组冠状动脉图像质量评分均值分别为（3.54±0.66）分和（3.58±0.72）分,差异无统计学意义（P〉0.05）;前门控与后门控两组有效放射剂量均值分别为（2.40±0.12）mSv和（9.97±1.02）mSv,差异有统计学意义（P〈0.05）,前门控低于后门控76.00%。结论心率在一定范围内时（〈70次/分）,64 MDCT前门控冠状动脉成像的图像诊断质量与后门控具有一致性,且前门控可明显降低放射剂量。     

低浓度对比剂、低辐射剂量婴幼儿腹部CT扫描

目的探讨使用低浓度对比剂(270mgI/ml)、低辐射剂量(管电压100kV)增强CT扫描在婴幼儿腹部CT检查的可行性。方法收集因腹部实体肿瘤或外伤需接受CT增强检查的婴幼儿90例,将其分为3组:A组为平扫与实质期管电压120kV、对比剂碘克沙醇(320mgI/ml);B组为平扫与实质期管电压100kV、对比剂碘克沙醇(320mgI/ml);C组为平扫与实质期管电压100kV、对比剂碘克沙醇(270mgI/ml)。采用4分制主观评价实质期图像质量。测量实质期的皮下脂肪标准差(SD),以及肝实质、脾实质、肾皮质、肾静脉和腹主动脉SNR和CNR,记录容积CT剂量指数(CTDI_(vol))、剂量长度乘积(DLP),并计算有效剂量(ED)。对3组数据进行统计学分析。结果 3组实质期肝实质、脾实质、肾皮质、肾静脉和腹主动脉的SNR、CNR及主观评分差异均无统计学意义(P均0.05)。3组CTDI_(vol)、DLP、ED差异有统计学意义(P均0.01)。A组CTDI_(vol)(P=0.001、0.002)、DLP(P=0.013、0.004)、ED(P=0.003、0.001)与B组、C组比较差异均有统计学意义,B、C组CTDI_(vol)、DLP、ED差异无统计学意义(P均0.05)。结论采用低浓度对比剂(270mgI/ml)联合100kV管电压进行CT增强扫描,可保证婴幼儿腹部图像的CNR,并满足临床诊断要求。     

Descending aortic dissection post coarctation repair in a patient with Turner's syndrome

Dissection of the descending aorta post coarctation repair in a patient with Turner's syndrome has rarely been described. A 45-year-old woman with Turner's syndrome had repair of coarctation by resection and interposition graft. Her postoperative course was uneventful. Chest X-ray two months postoperatively showed a hematoma in the proximal descending aorta, and a CT scan confirmed dissection distal to the coarctation repair, which was treated medically. Subsequent CT scanning one year later showed the hematoma resolving with no increase in the diameter of the dissected segment.     

双低剂量螺旋CT双期扫描在胸痛三联征的可行性研究

目的 探讨双低剂量肺动脉期与胸主动脉期螺旋CT双期扫描在胸痛三联征的可行性研究。方法 将收集于中山大学孙逸仙纪念医院的156例患者分为2组,观察组（39例）为急性胸痛患者,行双低剂量肺动脉期与胸主动脉期螺旋CT双期扫描,包括肺动脉CT血管造影（CTPA）（CTPA1组）、心脏冠状动脉CT血管造影（CCTA）（CCTA1组）和胸主动脉CT血管造影（TCTA）（TCTA1组）一次成像。常规组（117例）分别实施CTPA（CTPA2组,39例）、CCTA（CCTA2组,39例）和TCTA（TCTA2组,39例）。所有图像分别由两位医师重建并对其进行分级评分,分别记录、分析和比较两组图像质量、CT值、图像对比噪声比（CNR）和有效辐射剂量。结果 观察组肺动脉、心脏冠状动脉及胸主动脉与常规组的对应血管评分,K值分别为0.60、0.68和0.61,其一致性好。观察组与常规组对应血管图像的CNR及平均CT值均没有统计学差异（P>0.05）。观察组的有效辐射剂量与常规组中CCTA2组没有统计学差异（P>0.05）;观察组有效辐射剂量分别与常规组中CTPA2组及TCTA2组有统计学差异（P<0.05）,且常规组两组均高于观察组。结论 双低剂量螺旋CT双期扫描的图像质量满足临床需求且有效辐射剂量较低。     

Results of Lower Limb Revascularization from the Descending Thoracic Aorta

The aim of this retrospective study was to substantiate our results of lower limb revascularizations from the descending thoracic aorta. From November 1984 to November 1994, we used bypass grafting from the descending thoracic aorta to revascularize 69 lower limbs in 36 patients, 34 men and 2 women, whose mean age was 61.8 years. Patients were divided into two groups. Group I (primary indications) included 10 patients who had not had any prior lower limb arterial reconstruction. Group II (secondary indications) consisted of 26 patients who had had a prior arterial reconstruction that was either occluded or complicated. There were three early graft occlusions, all of them successfully treated. Complete flaccid, paraplegia occurred in one patient. Five patients presented with one or several late graft occlusions. Two patients had to undergo below-knee amputation, bilateral in one patient. Routine late control of the repair was performed by CT scanning, at a mean interval of 50.8 months. The good results recorded for bypasses revascularizing lower limbs from the descending thoracic aorta make this technique a satisfactory alternative when the abdominal aorta cannot be used.