HRCT扫描结合MSCT动态增强扫描在肺内孤立性结节的诊断价值

目的：评价HRCT扫描结合MSCT动态增强扫描在诊断肺内孤立性结节（SPNs）的价值。方法：收集直径小于3cm的肺内孤立性结节患者48例,其中周围型肺癌28例,单发转移瘤5例,肺炎性假瘤5例,结核瘤4例,肺血管瘤2例,支气管肺腺瘤2例、肺错构瘤2例。48例患者均先行常规胸部CT扫描,然后对兴趣区行HRCT扫描,然后行胸部动态增强扫描,并测量其CT值增强幅度。结果：HRCT扫描结合MSCT动态增强扫描诊断肺内孤立性小结节的正确率为90%,HRCT扫描可以更好显示病灶边缘特征及内部结构,动态增强扫描可见肺内恶性结节大多均匀增强,且增强CT值大于20HU,平均增强CT值为35HU。良性结节多周边增强,且增强CT值小于10HU。结论：根据SPNs的HRCT基本形态特征,并结合MSCT动态增强扫描强化特征有助于肺内孤立性结节的定性诊断,提高术前诊断正确率。     

肺泡微石症的影像学诊断

目的：探讨肺泡微石症的影像学特征。方法;报道肺泡微石症6例,全部病例均行胸部X线检查,2例行常规CT,1例行HRCT。并对全部影像学表现进行了回顾性分析。结果：6例胸片表现为弥漫粟粒样微细结节（2例）。“鱼子样”或“暴风沙样”（2例）、“白肺样”（1例）及高密度“面纱样”改变（1例）,CT可明确肺内微细结节的钙化密度,肺尖部气肿样改变及支气管血管束增粗并呈钙化密度,HRCT则可进一步显示肺野磨砂玻璃样改变,小叶间隔,叶间胸膜及支气管血管束钙化密度与串珠状增厚,小叶中心分布的微细结节与胸膜下蜂窝,结论：肺泡微石症是一种罕见病,其影像学表现具有特征性,影像学检查尤以HRCT检查对该病的诊断有决定性作用。     

孤立性肺结节的影像学分析

目的 探索孤立性肺结节的影像学征象，提高对本病的认识。方法 回顾性分析经临床和病理证实的40例孤立性肺结节的影像（X线，CT）表现。结果 40例孤立性肺结节包括23例周围型肺癌，10例结核球，4例球形肺炎，以及3例错构瘤。周围型肺癌23例，主要影像学表现：18例有分叶征，14例有毛刺征，13例有胸膜凹陷征，12例有血管集束征，4例有空气支气管征和空泡征；结核球10例，7例结节内有钙化，3例有卫星灶；球形肺炎4例，均表现为结节靠近胸膜生长呈中心密度高而周围密度较淡阴影；错构瘤3例，1例内部有脂肪密度，1例内部见爆米花样钙化。结论 正确认识孤立性肺结节的形态学特征、内部结构及合理运用相关的影像学检查方法能提高此类疾病的正确诊断率。     

双能量减影标准胸片和软组织像及MSCT 对肺转移癌检出率的比较

目的:比较DDR双能量减影标准胸片与软组织像及多层螺旋CT对转移性肺癌的检出率.材料和方法:对肿瘤患者胸片怀疑肺转移的行胸部DDR-DE和MSCT检查,随访时间为1.5～2年.结果:126例怀疑转移性肺癌患者,标准胸片检出90例,检出率为71.43%;软组织像胸片检出114例,其中58例为孤立性,56例为多发性,检出率为90.48%;DE两种胸片对肺内病变的检出率有高度统计学意义(P＜0.01).58例孤立性病变,行胸部MSCT扫描,结果为36例多发性(胸片为纵隔重叠及心影遮挡),20例孤立性(随访2～8个月后为多发性),2例未见病变(随访期内未见异常,考虑为纹理聚集所致).12例软组织像阴性患者MSCT检查,2例为多发性(胸片为心影后),10例未见病变(随访期内未见异常).软组织像和MSCT扫描的检出率无统计学意义(P＞0.05).结论:双能量减影软组织像对肺部小结节的特异性诊断有很大的提高,同时提高了转移性肺癌的早期检出率和敏感性,明显减低了标准胸片的漏诊、误诊.     

孤立性肺结节影像特征和误诊分析

目的探讨误诊的孤立性肺结节CT的影像特征,与病理结果对照,并分析误诊原因。方法选取CT诊断错误的30例孤立性肺结节病例,回顾性分析病灶的位置,大小,形状,内部密度,强化特点及影像学特征,以此分析其发生误诊的原因。CT误诊为恶性肿瘤为假阳性组,反之为假阴性组。结果1)结节分布:假阳性组病灶位于右肺上叶3例,右肺下叶4例,左肺上叶4例。假阴性组累及右肺上叶6例,右肺中叶1例,右肺下叶4例,左肺上叶4例,左肺下叶4例;2)强化特点:假阳性组表现为轻度强化4例,中度强化1例,重度强化1例。假阴性组表现为轻度强化1例,中度强化2例,重度强化1例;3)影像特征:假阳性组表现为分叶征7例,毛刺征8例,血管征象6例,胸膜牵拉3例,空泡征0例。假阴性组出现分叶征6例,毛刺征9例,血管征象15例,胸膜牵拉5例,空泡征5例。结论假阳性组误诊原因为病灶出现较多恶性征象,可通过对一些恶性征象的良性特征进行分析,假阴性组多因较少表现出明显的恶性征象而误诊,对血管有无侵犯以及空泡征等早期征象可以辅助诊断,但仍需穿刺活检以明确诊断。     

21例肺炎性假瘤的影像分析

目的 探讨能提高肺炎性假瘤诊断准确率的方法。方法 回顾性分析21例经手术病理证实的肺炎性假瘤的X线胸片和CT表现及相关临床资料。结果 肺炎性假瘤可有以下影像学特征：a）孤立的类圆形影，多位于肺的外周，可有浅分叶；b）大部分病灶密度均匀，边缘光整，少数病灶密度不均匀，边缘模糊，可有粗长毛刺或指向肺门的粗大纹理；c）病灶边缘可见平直征或桃尖征；d）病灶近肺门侧可见充气支气管征；e）病灶邻近胸膜局限性增厚、粘连，无胸腔积液；f）肺门及纵隔淋巴结无肿大。结论仅凭X线胸片易误诊为肺部肿瘤，掌握其CT特征并结合l临床资料，能明显提高肺炎性假瘤的诊断准确率。     

胸部结节病影像诊断值得注意的问题

目的 通过对胸部结节病误诊病例的回顾性分析，探讨结节病影像诊断存在的问题。方法 复习32例误诊病例的影像，包括胸片和胸部CT及临床资料。病理证实9例，临床治疗证实23例。结果 32例均有胸部淋巴结增大，其中23例纵隔淋巴结及两侧肺门淋巴结增大，5例纵隔淋巴结及单侧肺门淋巴结增大，4例纵隔淋巴结增大而无肺门淋巴结增大。肺部病变有24例，其中19例为肺内多发结节，肺部斑片状影4例，肺内纤维化1例。胸膜病变3例，均伴肺内多发结节，其中2例胸腔积液，1例胸膜多发小结节。结论 胸部结节病影像不典型时诊断困难，需结合临床或治疗中动态观察确诊。     

肺错构瘤的影像诊断

目的：分析肺错构瘤的影像学特征及鉴别诊断。方法：搜集1999年～2001年间经手术及病理证实的肺错构瘤患者15例，其中男9例，女6例。胸片检查9例，CT扫描6例，其中平扫3例，增强扫描3例。结果：主气管病变1例，中央形病变2例，周围型病变12例。右肺结节11例，左肺结节3例。病灶内钙化3例，有钙化和脂肪2例，均匀密度无钙化及脂肪10例。病变直径1～5cm。病变直径＜3cmll例，占73．3％。光滑圆形孤立结节11例，浅分叶及不规则形状4例。3例行CT增强扫描均无明显强化。本组肺措构瘤中33．3％(5／15)为典型措构角影像学表现：小结节直径＜3cm，边缘光滑，病灶内可见钙化和／或脂肪。非典型表现为66．7％(10／15)，包括大结节、浅分叶和不规则结节，结节均匀密度及位于主气管内。结论：爆米花样钙化和脂肪密度为肺错构瘤的典型征象。CT检查有助于鉴别非典型表现和肺内孤立性结节。     

胸部孤立性纤维瘤的MSCT表现

目的:探讨胸部孤立性纤维瘤的多层螺旋CT(MSCT)表现特征,提高对孤立性纤维瘤的认识和诊断水平.材料和方法:搜集经穿刺活检及手术病理证实的15例胸部孤立性纤维瘤,分析其MSCT表现特征.结果:1例为纵隔孤立性纤维瘤,14例为胸膜孤立性纤维瘤.5例密度均匀,增强后呈轻中度均匀强化,10例密度欠均匀,增强后呈不均匀"地图样"轻中度强化.6例可见钙化;11例可见假包膜.结论:胸部孤立性纤维肿瘤的MSCT表现有一定特征性,正确认识其CT的影像学特点,可以对绝大多数病例做出术前诊断.     

肺气肿的CT表现和临床应用研究

目的研究不同类型肺气肿的CT表现及临床应用。方法将33例尸检标本从气管灌注10％福尔马林，使肺膨胀至正常状态，1周后经气管注入氧气，直至液体全部从胸膜表面逸出，制成固定的充气标本，类似正常状态下肺组织，再将标本行冠状面及横轴面扫描。选取标本内有肺气肿的23例，分析其内肺气肿的表现及分布，然后将标本切成10mm厚层，进行CT、病理对照。对15例经病理或临床综合诊断证实的病例行螺旋CT扫描，包括肺气肿合并感染11例，合并孤立性结节4例，分析肺气肿合并症的CT特征。结果（1）23例肺气肿的标本中，小叶中心型肺气肿21例，全小叶型肺气肿5例，均与小叶中心型并发，间隔旁型肺气肿19例，瘢痕旁型肺气肿3例。（2）肺气肿均累及双侧肺野，呈大致对称或相近分布，17例（17／23）表现为2种或2种以上类型肺气肿并发。（3）肺气肿合并感染的14例（临床病例11例，标本3例）中，均见“假空洞”或“假蜂窝”影（实变肺野内未被充填的气肿腔）；肺气肿合并结节者4例，见“假胸膜凹陷征”（间隔旁气肿或肺大泡的壁与结节相连）。结论肺气肿的CT表现、分布及多种类型合并存在等特点对空腔性病变的鉴别有帮助。提出肺气肿合并症的CT特征，“假空洞”影、“假蜂窝”影、“假胸膜凹陷征”及其对临床诊断与鉴别诊断的作用。     

18F-FDG PET/CT结合高分辨率CT对孤立性肺结节的

 目的 探讨18F-FDG PET/CT显像结合高分辨率CT(high resolution CT,HRCT)对孤立性肺结节(solitary pulmonary nodule,SPN)的诊断价值。方法 回顾性分析124例SPN患者的18F-FDG PET/CT检查资料,其中76例加做HRCT扫描,所有病例经病理或临床随访证实。18F-FDG PET/CT通过目测法和半定量法判断病灶的代谢情况,结合CT或HRCT病灶的形态学特征判断良、恶性。结果 48例仅行18F-FDG PET/CT检查的SPN患者,正确诊断32例为恶性,8例为良性,假阳性与假阴性各4例。76例加做HRCT的患者,正确诊断62例恶性与8例良性,假阳性与假阴性分别为2例和4例。18F-FDG PET/CT 结合HRCT与单纯18F-FDG PET/CT诊断SPN的灵敏度、特异性及准确率分别为94%、80%、90%与89%、67%、83%。结论 18F-FDG PET/CT协同HRCT可提高对SPN性质判断的灵敏度、特异性及准确率。     

Solitary pulmonary nodules: potential role of dynamic MR imaging in management initial experience

PURPOSE: To evaluate the utility of dynamic magnetic resonance (MR) imaging in the management of solitary pulmonary nodules (SPNs). MATERIALS AND METHODS: Fifty-eight patients with 58 pathologic analysis-proved SPNs (diameter < 30 mm) underwent dynamic 1.5-T MR imaging. The 58 SPNs were classified into three groups at pathologic analysis: malignant SPNs (n = 38), active infections (n = 10), or benign SPNs (n = 10). From signal intensity-time curves generated after the bolus injection of contrast material, the maximum relative enhancement ratio and slope of enhancement were calculated and statistically compared among the three groups. Threshold values of these two dynamic MR indexes were determined on the basis of positive differentiations. RESULTS: The mean relative enhancement ratio and mean slope of enhancement for the malignant SPN group were significantly higher than those for the benign SPN group and significantly lower than those for the active infection group (P <.05). With 0.15 as the threshold maximum relative enhancement ratio for distinguishing the malignant SPN and active infection groups from the benign SPN group, the sensitivity, specificity, and accuracy were 100%, 70%, and 95%, respectively. With 0.025/sec as the threshold slope of enhancement, all SPNs with malignancy and active infection were clearly distinguished from benign SPNs. CONCLUSION: Dynamic MR indexes were useful in the differentiation between SPNs that necessitated further evaluation or treatment (malignancy and active infection) and SPNs that did not necessitate further evaluation or treatment (benign nodules).     

多层螺旋CT灌注评价孤立性肺结节首过血流模式

目的:探讨多层螺旋CT灌注在孤立性肺结节(SPN)首过时血流特征及鉴别诊断中的应用价值。方法:对99例直径2~4 cm的SPN先行32层螺旋CT平扫,再行多层同层连续动态增强扫描,在时间-密度曲线(TDC)的基础上,测量SPN增强峰值(PESPN)、病灶同层主动脉的增强峰值(PEAA)、病灶达峰时间(TTP),并由此计算增强净增值(NE)、结节-主动脉强化峰值比(S/A)、灌注量(Pr),进行统计学分析。结果:恶性与炎性SPN的PESPN、NE、S/A和Pr均高于良性SPN(P均<0.05),其TTP低于良性SPN(P<0.05);恶性SPN的PESPN、NE、S/A高于炎性SPN(P均<0.05);恶性结节的Pr高于炎性结节,但二者之间差异无显著性意义(P>0.05)。以NE≥25 HU作为恶性病变的阈值,其敏感度为98.2%,特异度为52.0%,准确度为86.9%,阳性预测值为85.6%,阴性预测值为92.9%。良性、恶性及炎性结节的TDC形态不同。结论:多层螺旋CT灌注成像技术是定量评价SPN血流模式的无创性技术,有助于SPN的鉴别诊断。     

Differentiation between benign and malignant solid pseudopapillary tumor of the pancreas by MDCT

Purpose

The purpose of this study was to determine if characteristic features on computed tomographic and (or) magnetic resonance imaging can differentiate benign and malignant solid pseudopapillary neoplasms (SPN).

Materials and methods

A total of 82 pathologically diagnosed SPN patients were included. CT and MRI were reviewed by 3 radiologists. Each tumor was analyzed through the clinical and imaging features.

Results

The highest occurrence of malignant SPN was observed in the group of patients (11–19 years old) followed by the group of patients (50–65 years old). When the tumor was located in the tail and the size was equal or larger than 6.0 cm, the positive and predictive value, the predictive value, sensitivity and specificity for a malignant SPN were 61.5%, 100%, 100% and 78.6%, respectively. Presence of complete encapsulation was more frequent in benign SPNs, but focal discontinuity in the malignant SPNs. Amorphous or scattered calcifications, all near-solid tumors and presence of upstream pancreatic ductal was found in the benign SPNs.

Conclusion

A focal discontinuity of the capsule, large tumor size (>6.0 cm) and a pancreatic tail location may suggest malignancy of SPN. In contrast, tumors with amorphous or scattered calcifications, and all near-solid tumors may be indicative of benignancy. Age (less than 20 or more than 50 years old) is a possible risk factor of SPN. In comparison to other pancreatic neoplasms, such as ductal adenocarcinoma, a complete/incomplete pseudo-capsule, without upstream pancreatic duct dilatation and lymph nodes metastasis, and the presence of internal calcification and hemorrhage are more likely SPN.     

良、恶性孤立性肺结节支气管征的相关性研究

目的：分析孤立性肺结节的支气管征的表现形式,研究孤立性肺结节的良恶性与其支气管形态学改变的相关性,探讨其临床应用价值。方法：54例直径≤3cm的SPN患者（其中恶性结节32例,良性结节22例）行全肺层厚为10mm螺旋扫描,并对病灶进行薄层扫描。所有患者平扫的原始数据以2.5mm进行标准算法薄层重建,将数据传入GE-AW4.0工作站进行图像后处理,分别以多平面重组（MPR）、曲面重组（CPR）、最大密度投影（MIP）、最小密度投影（MIP）及表面遮盖显示（SSD）等方法显示SPN与支气管的关系。将结果与手术病理组织对照。结果：①全肺层厚为10mm螺旋扫描,并对病灶进行薄层扫描。全肺扫描行层厚为2.5mm的标准算法薄层重建,结合各种工作站后处理方法,能极好的显示SPN与相关支气管的关系及形态特征;②54例SPN中与支气管有关系的43例（79.6%）,其中恶性结节29例（90.6%）,良性结节14例（63.6%）。其差异有显著性意义（P〈0.05）;③SPN-支气管关系分为5型：Ⅰ型支气管于SPN边缘被截断;Ⅱ型支气管进入SPN内并变尖、变细或锥状中断;Ⅲ支气管穿过SPN,其管腔通畅;Ⅳ型支气管沿SPN边缘走行而不中断,支气管壁增厚、牵拉;Ⅴ型,支气管沿SIN边缘走行而不中断,支气管壁无改变;④SPN与支气管关系大部分表现为单型,亦可表现为多型共存。恶性结节中均以Ⅰ型、Ⅱ型和Ⅲ型最常见,良性结节以Ⅰ型和Ⅲ型最常见。Ⅱ型主要见于恶性结节,不见于良性结节,其差异有显著性意义（P〈0．05）。Ⅲ型表现在良性结节中明显高于恶性结节,其差异有显著性意义（P〈0．05）。结论：多层螺旋CT螺旋扫描及薄层扫描合并薄层重建能清楚显示SPN与支气管关系及类型,两者关系对SPN良恶性性质的诊断和鉴别有重要价值。     

MSCT 灌注成像对孤立性肺结节的诊断价值

目的：评价多排螺旋 CT(MSCT)灌注成像对孤立性肺结节(SPN)的诊断价值。方法收集手术病理确诊的 SPN 60例,分为2组。研究组32例为肺癌,对照组28例为良性结节,术前行64排螺旋 CT 灌注成像,比较2组的灌注成像参数差异,并将灌注成像与常规增强扫描的诊断效果进行比较。结果研究组的血容量(BV)、血流量(BF)、表面通透性(PS)均高于对照组,平均通过时间(MTT)则低于对照组(P<0.01)。灌注成像对肺癌的诊断敏感性、对 SPN 的诊断准确性均显著高于增强扫描(P <0.01)。结论MSCT 灌注成像对 SPN 具有更高的诊断价值。     

The performance of<Superscript> 18</Superscript>F-fluorodeoxyglucose positron emission tomography in small solitary pulmonary nodules

Solitary pulmonary nodule (SPN, intraparenchymal lung mass <3 cm) is often a diagnostic challenge. This study was performed to evaluate the diagnostic accuracy of ¹⁸F-fluorodeoxyglucose positron emission tomography (FDG PET) in radiologically indeterminate SPN 10 mm on spiral CT. Between August 1997 and March 2001, we identified all patients with radiologically indeterminate SPNs 10 mm who were referred for FDG PET imaging at the VU University Medical Centre. All PET scans were retrospectively reviewed by an experienced nuclear medicine physician. PET was considered positive in cases with at least moderately enhanced focal uptake, and otherwise as negative. Lesions were considered benign on the basis of histology, no growth during 1.5 years or disappearance within at least 6 months. Thirty-five patients with 36 SPNs 10 mm in diameter at clinical presentation were identified (one patient had two metachronous lesions). In 13 of 14 malignant nodules and in two of 22 benign nodules, diagnosis was confirmed by histology. Prevalence of malignancy was 39%. PET imaging correctly identified 30 of 36 small lesions. One lesion proved to be false negative on PET (CT: 10 mm), and in five lesions, PET scans proved to be false positive. Specificity was 77% (17/22; 95% CI: 0.55–0.92), sensitivity 93% (13/14; 95% CI: 0.66–1.0), positive predictive value 72% (13/18; 95% CI: 0.46–0.90) and negative predictive value 94% (17/18; 95% CI: 0.73–1.0). This retrospective study suggests that FDG PET imaging could be a useful tool in differentiating benign from malignant SPNs 10 mm in diameter at clinical presentation. Such results may help in the design of larger prospective trials with structured clinical work-up.     

Value of multiplanar reconstruction in MSCT in demonstrating the relationship between solitary pulmonary nodule and bronchus

In this report, we studied the value of the solitary pulmonary nodule (SPN)–bronchus relationship in determining the nature of SPN by multiplanar reconstruction (MPR) in multislice spiral computed tomography (MSCT). One hundred forty-eight SPN cases were enrolled. CT was performed in all cases using MSCT. Images were then transferred to a processing workstation for MPR. The results showed that MPR is a valuable tool for visualizing the SPN–bronchus relationship and that the SPN–bronchus relationship is useful in determining the nature and the degree of differentiation of SPN.     

Efficiency of 18F-FDG and 99mTc-depreotide SPECT in the diagnosis of malignancy of solitary pulmonary nodules

Purpose The purpose of the study was to compare ¹⁸F-fluorodeoxyglucose (FDG) positron emission tomography (PET) and ^99mTc-depreotide single-photon emission computed tomography (SPECT) in the diagnosis of malignancy of solitary pulmonary nodules (SPNs).Methods Twenty-eight patients without any history of cancer and presenting an SPN (0.8–3 cm in size) underwent FDG PET and depreotide SPECT. Depreotide SPECT and FDG PET were performed on a double-head gamma camera and a dedicated PET scanner respectively. Twenty-five out of 28 lesions were removed by thoracotomy or assessed by biopsy (n=1) and histologically examined. A strategy of serial CT scanning was adopted in the three remaining patients.Results Histological findings revealed 18 malignant nodules and seven benign lesions. Stability over a 2-year period indicated a benign process in the remaining three cases. Both techniques yielded true positive results in 15 of the 18 cancers. FDG PET identified two additional adenocarcinomas not detected by depreotide SPECT. A carcinoid tumour not visualised on FDG PET was identified by depreotide SPECT. Seven of the ten benign lesions did not reveal tracer uptake on either depreotide SPECT or FDG PET. Both techniques showed false positive results for the same two lesions. One more false positive was seen on FDG PET. FDG PET and depreotide SPECT had a sensitivity of 94.4% and 88.9% respectively; this difference was not significant. In our experience, depreotide SPECT and FDG PET are equally sensitive (92.3%) for large (>1.5 cm) and equally specific (85.7%) for small (up to 1.5 cm) SPNs suspicious for malignancy.Conclusion This study showed ¹⁸F-FDG PET to be more sensitive than ^99mTc-depreotide SPECT in the diagnosis of malignancy of SPNs. However, the combination of both techniques may provide additional accuracy.     

DDR双能量减影软组织像检出肺小结节的临床价值

目的: 探讨双能量减影软组织像检出肺小结节的价值.材料和方法: 对84例X线胸片发现肺小结节的患者进行DDR-DE和MSCT的检查.结果: 84例肺小结节检出情况: 胸片196个,DDR-DE软组织像157个,MSCT 160个.DDR-DE与胸片相比排除肺小结节55个、增加肺小结节16个.其中排除肺小结节17例,增加肺小结节数12例,减少肺小结节数16例.MSCT与DDR-DE相比排除肺小结节6个,增加肺小结节9个.结论: DDR-DE软组织像比X线胸片明显提高肺小结节的检出率,减少了误诊.