碘造影剂推注速度对肝脏CT增强扫描强化程度的影响

目的探讨适宜的碘造影剂推注速度,提高肝脏CT增强扫描强化程度,提高肝脏病变的检出率和诊断的准确性。方法将90例肝脏CT增强扫描患者随机分为2mL/s组、3mL/s组、5mL/s组各30例,分别以2mL/s、3mL/s、5mL/s速度静脉推注碘造影剂,使用多层CT行肝脏扫描测量并对比肝实质、主动脉CT值。结果三组肝实质CT值比较,差异有统计学意义(P0.01),2mL/s组与3mL/s组、5mL/s组比较,差异有统计学意义(均P0.01);三组主动脉CT值比较,差异有统计学意义(均P0.01)。结论行肝脏CT增强扫描时,3mL/s注射流速可使肝脏达到较好的强化效果;5mL/s注射流速可使CT血管造影达到较好的强化效果。     

3种静脉通路在肿瘤患者CT增强扫描对比剂高压注射中的应用比较

目的 比较不同静脉通路用于CT增强扫描对比剂高压静脉注射的效果,为肿瘤患者选择合适的静脉通路提供实证依据。 方法 将200例CT增强扫描肿瘤患者,按不同的对比剂高压静脉注射通路分为三组,分别为22G（巴德）留置针（留置针组,88例）,耐高压注射针头输液港（输液港组,55例）,耐高压PICC导管（PICC组,57例）。均采用高压注射泵输注碘佛醇注射液（1.5 mL/kg）,调整最大压力不超过324 psi,流速1.6~2.5 mL/s。记录并比较三组对比剂注射流速、静脉通路压力、对比剂注射时间,以及患者注射部位的胀痛感和图像扫描质量。 结果 三组对比剂注射流速、静脉通路压力和对比剂注射时间,以及注射时胀痛程度和图像扫描质量比较,差异有统计学意义（均P＜0.05）;其中留置针组流速最高［（2.30±0.16）mL/s］,压力最低［（48.58±3.15）psi］,注射时间最短［（35.12±4.88）s］,患者的胀痛感最轻（秩均值70.50）,图像扫描质量最优（秩均值73.51）。 结论 在CT增强定位高压静脉注射对比剂时,采用22G留置针效果优于耐高压PICC和输液港。     

对比剂注射部位对儿童复杂先天性心脏病双源CT成像的影响

目的探讨对比剂注射部位对儿童复杂先天性心脏病CTA图像质量的影响。方法回顾性分析426例复杂先天性心脏病患儿的双源CT心脏大血管CTA图像,其中经上肢静脉注射154例(A组),以下肢静脉注射272例(B组),对A、B组CTA图像上腔静脉对比剂硬化束伪影,心腔、大血管CT值,右心房、右心室对比剂均匀度,心内结构及大血管显示清晰度进行对比。结果 A组图像上腔静脉内对比剂硬化束伪影评分为3.00±1.04,B组为3.96±1.08,优于A组,二者差异有统计学意义(P0.01),两组心腔、大血管平均CT值的差异均无统计学意义(P均0.05);两组心内结构、大血管、冠状动脉起源及近段图像清晰度主观评分差异均有统计学意义,B组均高于A组(P均0.05),而右心房、右心室对比剂均匀度评分的差异无统计学意义(P均0.05)。结论对比剂注射部位的选择对儿童先天性心脏病CTA图像质量有显著影响,经下肢浅静脉注射对比剂有助于消除上腔静脉对比剂伪影,提高图像质量。     

不同对比剂注射流率对颈部增强MRA图像质量的影响

目的 分析不同对比剂注射流率对颈部动脉增强血管成像（3D CE-MRA）图像质量的影响,探讨获得高质量颈部CE-MRA图像的最优对比剂注射流率。方法 收集怀疑颈部血管病变而行颈部增强MRA扫描的患者,根据注射流率不同分为三组,其中A组1 mL/s共22例,B组2 mL/s共25例,C组3 mL/s共20例。由两名主治医师对各节段的动脉图像质量及静脉污染程度分别进行评分,计算整体动脉平均分和静脉污染平均分;分别测量头臂干、左颈总动脉、左锁骨下动脉、双侧颈总动脉分叉下1 cm处及双侧同水平椎动脉、双侧颈内动脉海绵窦段（C4）及基底动脉的信号强度（SI）,计算整体动脉血管信号平均值及整体血管、对比噪声比（CNR）。结果 A、B、C三组动脉血管信号平均值分别为584、720、690;动脉血管对比噪声比（CNR）平均值分别为222.50、272.94、280.22,以上指标三组总体具有统计学意义（SI H=8.29,P=0.016;CNR H=7.56,P=0.023）。动脉、静脉及整体评分均具有统计学差异（P<0.05）,其中动脉评分A组与B组及A组与C组具有统计学差异（P<0.017）,B组与C组不具有统计学差异（P>0.017）,静脉污染评分A组与C组具有统计学差异（P<0.017）,而A组与B组及B组与C组不具有统计学差异（P>0.017）,整体评分中A组与B组及A组与C组具有统计学差异（P<0.017）,B组与C组不具有统计学差异（P>0.017）。结论 随注射流率的增加颈动脉血管的信号强度增加,图像信噪比增加,而静脉污染没有增加,故行颈部CE-MRA时推荐注射流率为3 mL/s可取得高质量的血管成像效果。     

第三代双源CT个体化“双低”技术在冠状动脉成像中的应用

目的探讨第三代双源CT冠状动脉成像中应用低对比剂剂量、低对比剂注射流率技术的个体化注射方案对图像质量及辐射剂量的影响。方法将120例接受CT冠状动脉成像的患者随机分为2组。试验组:按照公式对比剂剂量=体质量×0.6ml/kg、流率=对比剂剂量/(5+扫描曝光时间),计算对比剂剂量和流率;对照组:对比剂50ml,流率5.0ml/s。2组均采用前瞻性心电门控窄窗技术扫描,比较2组图像质量的客观和主观评价指标及辐射剂量。结果试验组与对照组患者性别、年龄、体质量、体质量指数差异均无统计学意义(P均0.05)。试验组与对照组注射对比剂剂量和对比剂流率差异均有统计学意义(P均0.001)。2组图像SNR、冠状动脉图像质量评分和冠状动脉的可评价率差异均无统计学意义(P均0.05)。心率≤70次/分、70次/分心率≤80次/分及心率80次/分时,试验组和对照组患者有效辐射剂量差异均有统计学意义(P均0.05)。结论第三代双源CT冠状动脉血管成像个体化注射方式可在满足临床诊断的前提下最大程度地减少对比剂用量。     

同步与非同步扫描对CT数字减影血管造影图像质量的影响

目的探讨同步与非同步扫描对64层容积CT数字减影血管造影（VCTDSA）图像质量的影响。方法建立紧贴骨结构的血管模型,采用64层螺旋CT进行扫描：①未注射对比剂螺旋扫描20次,球管曝光时间为2.1s,扫描间隔时间分别为1.9s、3.9s、5.9s、7.9s、9.9s、11.9s、13.9s、15.9s、17.9s、19.9s,2.9s、4.9s、6.9s、8.9s、10.9s、3.0s、4.0s、5.0s、6.0s、7.0s。②注射对比剂后螺旋扫描10次,扫描间隔时间分别为9.9s、11.9s、13.9s、15.9s、17.9s,10.9s、12.9s、11.0s、12.0s、13.0s,其余扫描参数同①。减影后数据行3D容积再现（VR）及最大密度投影（MIP）图像重组,评价减影后图像质量、测量减影后全幅图像CT值、记录球管曝光角度差。结果注射对比剂前后同步扫描15次,减影后图像质量均为Ⅰ级,非同步扫描15次,减影后图像质量Ⅰ级2次、Ⅱ级12次、Ⅲ级1次;20次未注射对比剂减影后图像CT值比较,非同步扫描减影后图像CT值均数高于同步扫描;同步扫描的球管曝光角度差均数明显小于非同步扫描。结论同步扫描保证球管曝光的起始位置相同,可明显提高VCTDSA的图像质量。     

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。     

MSCT下肢动脉血管成像扫描方案优化

目的探讨128层螺旋CT下肢CTA的最佳扫描方案。方法将60例接受下肢动脉CTA检查的患者随机均分成6组,优化组管电流300mA,层厚0.625mm,对比剂流率4ml/s,注射剂量100ml;其余各组只变动其中1个扫描参数,其他参数同优化组。高毫安组管电流为400mA,低毫安组管电流为200mA,大层厚组层厚为5mm,多对比剂组对比剂注射剂量为130ml,高流率组对比剂流率为4.5ml/s。记录扫描延迟时间;测量腹主动脉水平、股深浅动脉分叉水平、胫前后动脉上段水平、足背动脉水平的CT值;评价各组图像质量,并与优化组进行对比。结果优化组与高毫安组、多对比剂组、高流率组图像质量差异均无统计学意义(P均>0.05);优化组与低毫安组、大层厚组间图像质量差异均有统计学意义(P均<0.05)。结论应用128层螺旋CT机行下肢CTA扫描,采用管电流300mAs、层厚0.625mm、对比剂流率4ml/s、注射剂量100ml时图像质量优良率高,能够满足诊断要求。     

先天性心脏病患儿造影增强磁共振血管成像检查的护理配合

目的探讨对先天性心脏大血管疾病患儿施行造影增强磁共振血管成像(CE-MRA)检查的护理方法。方法对30例先天性心脏大血管疾病患儿进行CE-MRA检查,患儿经镇静制动后,手动静脉注射对比剂0.4mmol/kg,注射后5～10s开始进行造影增强的磁共振血管成像扫描。结果检出法洛四联症12例,主-肺动脉间隔缺损3例,动脉导管未闭8例,先天性主动脉弓缩窄畸形2例,先天性主动脉弓缩窄畸形伴动脉导管未闭5例。图像质量优28例,良2例。结论 CE-MRA检查可获得精确的影像资料。检查前采用6%水合氯醛保留灌肠镇静制动,正确选择血管建立静脉通道,准确掌握推注造影剂和扫描延迟时间,可保证检查的顺利完成,为临床诊断提供优质的影像图像。     

MSCT在介入治疗泌尿系统医源性出血中的应用

目的探讨术前MSCT增强扫描对介入治疗泌尿系统不同部位医源性出血的价值。方法回顾性分析27例因泌尿系统不同部位医源性出血接受介入治疗患者的资料,比较术前MSCT增强扫描与术中首次DSA对出血责任血管的检出率,分析CT及DSA征象。结果 26例(26/27,96.30%)经术前MSCT增强扫描明确出血责任血管,主要表现为动脉期斑片状对比剂外溢、对比剂浓聚及肾静脉早期显影征象;1例未明确责任血管患者DSA可见动静脉瘘征象。24例(24/27,88.89%)经术中首次DSA明确出血责任血管,主要表现为对比剂外溢、假性动脉瘤及肾动静脉瘘;3例未明确责任血管患者术前MSCT增强扫描表现为对比剂外溢2例、肾静脉早期显影1例,术中参考术前增强MSCT表现调整后再次造影均明确责任血管。术前MSCT增强扫描与术中首次DSA对出血责任血管的检出率的差异无统计学意义(2χ=1.08,P=0.29)。结论介入治疗前MSCT增强扫描可较为准确地判定泌尿系统不同部位医源性出血责任血管,且对术中首次DSA无法明确出血责任血管患者可根据术前MSCT表现对DSA进行调整,从而快速、准确地进行栓塞。     

Two‐year audit of computed tomographic colonography in a teaching hospital: are we meeting the standard?

Objective We aimed to determine whether adopting the published recommendations has led to successful implementation of computed tomographic colonography (CTC) in a teaching hospital setting outside the context of a clinical trial. Method An audit of all the CTC examinations between April 2005 and June 2007 was conducted to determine the following: adequacy of bowel preparation, CTC indications and findings (compared with available colonoscopy), complications and experience of reporting radiologist. Results The most common indications for the 111 CTC patients reviewed included exclusion of synchronous colonic tumours, incomplete colonoscopy and altered bowel habit. Only 16% of ascending colon/caecal segments was clear of faecal or fluid contamination. The rectum and sigmoid colon were free of contamination in 78% and 74% of cases respectively. Appropriately trained radiologists reported 91% of studies. Thirty‐two percent of studies were normal. The most common positive findings were diverticular disease or a rectal tumour. Sensitivity, specificity and positive predictive value were 89%, 94% and 90% respectively (all polyps) with a sensitivity of 98.5% for lesions > 5 mm in size. Twenty‐five percent of patients had extra colonic abnormalities. There were no recorded complications. Conclusion Our CTC practice is within accepted published guidelines. Bowel preparation is suboptimal in a significant proportion of cases and faecal tagging is being implemented.     

Emission and transmission tomography of the brain in cerebrovascular disease

Transmission and emission computed tomography (T-CT and E-CT, respectively) scans of the brain in 149 patients with cerebrovascular disease were compared to establish the diagnostic accuracy of the two methods. The T-CT scan yielded an overall rate of true-positive results of 80.75% in major infarcts, 80% in intracerebral hematomas, and 75.9% in subarachnoid hemorrhage. In contrast, the percentages of true-positive results yielded by the E-CT scan were 92.3, 55, and 34.5%, respectively, in each type of cerebrovascular disease. The false-negative results obtained with the T-CT scan were higher in infarcts but lower in hematomas and subarachnoid hemorrhage; the reverse was true for the diagnoses obtained with the E-CT scan. The false-positive diagnoses produced by the T-CT scan were high for hemorrhagic strokes compared to those of the E-CT scan. The diagnostic sensitivity of each scan was not affected by the location of the lesion. Thus, the E-CT scan is more sensitive for thromboembolic disease and less so for hemorrhagic types of stroke. The reverse is true for the T-CT scan.     

Role of fluorine-flurodeoxyglucose positron emission tomography/computed tomography in preoperative assessment of anterior mediastinal masses

Objective: The purpose of the study was to explore the usefulness of fluorine-fluorodeoxyglucose positron emission tomography/computed tomography (F-FDG PET-CT) in the preoperative assessment of isolated anterior mediastinal lesions, especially in the planning of operative strategy (biopsy or upfront resection). Methods: During the last 36 months, 19 consecutive patients (10 males, mean age 54 ± 16 years) underwent PET-CT in the preoperative work-up of isolated anterior mediastinal diseases. Maximal transverse diameter at CT and the postoperative histology and Masaoka staging for thymomas were collected and related to the maximum standardised uptake values (SUVs). Thymomas were divided into low-risk thymoma (LRT = A, AB and B1) and high-risk thymoma (HRT = B2, B3 and C). Results: There were 13 thymomas (six LRT and seven HRT), three lymphomas and three other primitive thymic tumours (one paraganglioma, two non-seminomatous germ cell tumours). In LRT, the mean SUV was 3.3 ± 0.5 resulting significantly lower than HRT, 13.5 ± 7 (p = 0.009). The SUV in LRT was also significantly lower with respect to lymphoma, 12.4 ± 4 (p = 0.001), and the other primitive anterior mediastinal tumours, 8 ± 0.8 (p = 0.001). Between thymomas we found a significant correlation between Masaoka stage and SUV, r = 0.718, p = 0.006. No correlation was found between transverse diameters and SUV, r = 0.141, p = 0.6. Conclusions: In our experience, low SUV (<5) is associated with LRT and minimal invasive thymoma (Masaoka stages I–II) and, therefore, susceptible to upfront surgery. For lesions with an infiltrative aspect on CT scan associated with a higher SUV (>5), an open biopsy is mandatory to exclude mediastinal lymphomas or, in case of HRT, to address a neoadjuvant treatment.     

Ossifying fibroma of the frontoethmoid sinus

We report the case of a woman with ossifying fibroma of the right frontoethmoid sinus. Computed tomography and hypocycloidal tomography were useful in identifying the lesion and its extension into the intracranial and intraorbital cavity.     

Noninvasive Differential Diagnosis of Pulmonary Nodules Using the Standardized Uptake Value Index

Objectives: We previously showed that the standardized uptake value (SUV) index, which was defined as the ratio of the maximum SUV of the tumor to mean SUV of the liver, was a surrogate marker of lung cancer aggressiveness. In this study of patients with pulmonary nodules (PNs), we explored whether the SUV index could be used to differentiate small malignant from small benign PNsMethods: A total of 284 patients with solitary PNs ≤2 cm in size underwent positron emission tomography/computed tomography and surgery. The associations between pathological findings and clinical factors were evaluated.Results: The median SUV indices of lung cancer, metastatic PNs and benign nodules were 1.2, 1.5, and 0.6, respectively (P <0.01). A SUV index cut-off value of 1.2 was used to differentiate benign from malignant nodules. When patients were grouped according to SUV index cut-off values of <1.2 or ≥1.2, the following cases were false-negative: lung adenocarcinoma (P <0.01), kidney as primary site (P <0.01), and metastatic PNs with long disease-free survival (P = 0.02).Conclusions: As a noninvasive diagnostic marker, the SUV index was found to be useful for differentiating benign from malignant small PNs.     

Primary oligodendroglioma of the lateral ventricle with computed tomographic and positron emission tomographic evaluations

Two cases of primary intraventricular oligodendrogliomas are presented. Total excisions of well-demarcated large tumors in the lateral ventricle were successfully performed in young women by means of a frontal transventricular approach. An evaluation by computed tomography and positron emission tomography was attempted to obtain definite diagnosis of not only the location of the tumor but also the histologic grade of malignancy.     

A case of sclerosing angiomatoid nodular transformation of the spleen with increased accumulation of fluorodeoxyglucose after 5-year follow-up

IntroductionSclerosing angiomatoid nodular transformation (SANT) of spleen is a new entity defined as a benign pathologic lesion. Fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) shows weak accumulation, thereby ruling out the malignancy in preoperative diagnosis is difficult. Herein, we reported a case of shrinking SANT with increased FDG accumulation during a 5-year follow-up period, which was treated by laparoscopic splenectomy.Presentation of caseA 64-year-old female had been referred to our hospital for the evaluation of a splenic tumor. Initial contrast-enhanced computed tomography (CT) showed a well-defined, and ovoid hypoattenuating lesion, measuring 52 mm in diameter in the spleen. Initial PET/CT revealed accumulation of FDG in the tumor (maximum standardized uptake value [SUVmax]: 2.8). The mass was diagnosed as SANT, and the patient was followed-up every 6–12 months for 5 years. Follow-up PET/CT revealed increased accumulation of FDG (SUVmax: 3.5). As it was suspicious considering the differential diagnosis, including malignant lymphoma and inflammatory pseudotumor, she underwent laparoscopic splenectomy. The pathological results showed three types of vessels including capillaries, ectatic small veins, and sinusoids-like vessels, consistent with the features of SANT.DiscussionA SANT may have features that resemble those of malignancy, including the growing mass and the increase of FDG accumulation.ConclusionAlthough the preoperative diagnosis of SANT is difficult, it is necessary to make a diagnosis of SANT comprehensively, even when accumulation of FDG increased slightly during the follow-up period and suggested the possibility of malignant diseases.     

增强CT和PET/CT对胰腺癌诊断及分期中的价值

目的 探讨增强CT和PET/CT对胰腺癌诊断及分期中的价值.方法 回顾性分析安徽医科大学第一附属医院普外科2009年10月至2013年10月间收治47例手术治疗的胰腺占位患者资料.术前均行CA19-9检查、腹部增强CT扫描及全身PET/CT扫描,比较增强CT与PET/CT在胰腺癌诊断及分期中价值.结果 47例患者中,确诊胰腺癌41例,非胰腺癌6例.CA19-9、增强CT和PET/CT对胰腺癌诊断的灵敏度分别为78.0％、80.4％和95.1％,PET/CT灵敏度优于CA19-9和增强CT,差异有统计学意义（P值分别为0.023和0.043）;在胰周淋巴结转移判断方面,PET/CT和增强CT的灵敏度分别为75.0％和41.6％,二者差异有统计学意义（P=0.019）;在肝转移判断方面,PET/CT和增强CT诊断的灵敏度分别为80.0％和60.0％,二者差异无统计学意义（P=1.0）.结论 PET/CT对胰腺癌诊断有较高灵敏度,显著优于增强CT.当肿瘤SUV值升高,PET/CT诊断仍应注意结合CA19-9、增强CT甚至MRI综合判断;PET/CT有助于发现淋巴结和远处器官转移病灶,获得更加准确的术前分期,从而避免诊断性剖腹探查手术.