CT虚拟结肠镜课件

1、CT虚拟(xn)结肠镜福建医科大学附属福建医科大学附属(fsh)协和医院协和医院 CT室室第一页，共二十七页。CT虚拟结肠镜2前 言 在美国是肿瘤发病率中居第三位 2009年有近146970例新发病例(bngl) 占肿瘤死亡的第二位 2009年全美有49920例死亡 超过100万的美国人患有结肠直肠癌第二页，共二十七页。CT虚拟结肠镜3结肠(jichng)直肠癌 遗传性非息肉(xru)性结肠直肠癌家族性多发性腺癌CENTERS FOR DISEASE CONTROLAND PREVENTION第三页，共二十七页。CT虚拟结肠镜4危险度因子(ynz)- 息肉分类 异常增生 较小癌变可能 腺瘤样

2、大约90%结肠直肠癌由腺瘤样息肉(xru)发展而来第四页，共二十七页。CT虚拟结肠镜5结肠(jichng)腺瘤进展小腺瘤 10mm 癌10 yrs 大多数是增生改变通常不会发展为癌症第五页，共二十七页。CT虚拟结肠镜6筛查的优势(yush) 预防癌症 切除癌前病变（恶性息肉）防止癌症发生 提高生存率早期检测显著增加长期(chngq)生存机会第六页，共二十七页。CT虚拟结肠镜7筛查的优势(yush)第七页，共二十七页。CT虚拟结肠镜8结肠(jichng)直肠癌筛查率 只有40%的结肠直肠癌在早期(zoq)阶段发现 近一半多一点的超过50岁的美国人有进行近期的结肠直肠癌筛查。*varies bas

3、ed on data source第八页，共二十七页。CT虚拟结肠镜9近年来光学(gungxu)直肠镜检查的普及率 (%)的趋势, 大于50岁的美国人, 1997-2004*A flexible sigmoidoscopy or colonoscopy within the past five years. Note: Data from participating states and the District of Columbia were aggregated to represent the United States. Source: Behavioral Risk Factor

4、Surveillance System CD-ROM (1996-1997, 1999) and Public Use Data Tape (2001, 2002, 2004), National Center for Chronic Disease Prevention and Health Promotion, Centers for Disease Control and Prevention and Prevention, 1999, 2000, 2002, 2003, 2005. 第九页，共二十七页。CT虚拟结肠镜10近年来粪便潜血试验(shyn)的普及率 (%)的趋势, 大于50岁

5、的美国人, 1997-2004*A fecal occult blood test within the past year. Note: Data from participating states and the District of Columbia were aggregated to represent the United States. Source: Behavioral Risk Factor Surveillance System CD-ROM (1996-1997, 1999) and Public Use Data Tape (2001, 2002, 2004), N

6、ational Center for Chronic Disease Prevention and Health Promotion, Centers for Disease Control and Prevention and Prevention, 1999, 2000, 2002, 2003, 2005. 第十页，共二十七页。CT虚拟结肠镜11结肠(jichng)直肠癌筛查率低:原因 (依照患者的说法) 对结肠直肠癌不重视 缺乏对结肠直肠癌筛查好处(ho chu)的了解 害怕, 难为情, 不舒服 没时间 费用高 “我医生从来没跟我提到过!”第十一页，共二十七页。CT虚拟结肠镜12The

7、2008 CRC Guidelines Update was a Joint Effort of 5 Organizations American Cancer Society U. S. Multi-Society Task Force on Colorectal Cancer American Gastroenterological AssociationAmerican College of GastroenterologyAmerican Society of Gastrointestinal Endoscopists American College of Radiology第十二页

8、，共二十七页。CT虚拟结肠镜13CRC Screening Guidelines: What Else is New? Two new tests recommended: stool DNA (sDNA) and computerized tomographic colonography (CTC) sometimes referred to as virtual colonoscopyThe guidelines: establish a sensitivity threshold for recommended testsdelineate important quality-relat

9、ed factors for each form of testing continue to emphasize options for testing An overriding goal of this update is to provide a practical guideline for physicians and the public第十三页，共二十七页。CT虚拟结肠镜142008 CRC Screening GuidelinesAverage risk adults age 50 and olderTests that detect adenomatous polyps a

10、nd cancer Flexible sigmoidoscopy (FSIG) every 5 years*, or Colonoscopy every 10 years, or Double contrast barium enema (DCBE) every 5 years*, or CT colonography (CTC) every 5 years* Tests that primarily detect cancer Annual guaiac-based fecal occult blood test (gFOBT)* with high test sensitivity for

11、 cancer, or Annual fecal immunochemical test (FIT)* with high test sensitivity for cancer, or Stool DNA test (sDNA)*, with high sensitivity for cancer, interval uncertain *Note: All positive screening tests should be followed up with colonoscopy第十四页，共二十七页。CT虚拟结肠镜15原 理第十五页，共二十七页。CT虚拟结肠镜16CT虚拟(xn)结肠镜

12、( CT Colonography，CTC)第十六页，共二十七页。CT虚拟结肠镜17CT虚拟(xn)结肠镜 ( CT Colonography，CTC)CTC 图像(t xin)光学(gungxu)结肠镜第十七页，共二十七页。CT虚拟结肠镜18CT Colonography 3-D viewPolyp2-D viewCourtesy of Beth McFarland, MD第十八页，共二十七页。CT虚拟结肠镜19CT Colonography: Rationale Allows detailed evaluation of the entire colon Minimally invasiv

13、e (rectal tube for air insufflation) No sedation required A number of studies have demonstrated a high level of sensitivity for cancer and large polyps第十九页，共二十七页。CT虚拟结肠镜20CTC vs. Optical Colonoscopy: Sensitivities for All PolypsPolyp Size10mm8mm6mmCTC92.2%92.6%85.7%Colonoscopy88.2%89.5%90.0%Pickhard

14、t et al, NEJM 2003第二十页，共二十七页。CT虚拟结肠镜21CTC: Additional Findings CTC identified 55 polyps not seen on initial colonoscopy 21 adenomas One 11 mm malignant polyp Extra-colonic findings 5 asymptomatic cancers Aortic aneurysms Renal and gall bladder calculiPickhardt et al, NEJM 2003第二十一页，共二十七页。CT虚拟结肠镜22CT

15、C: Follow-up colonoscopyIndication for diagnostic/therapeutic colonoscopy varies markedly based on selected polyp size thresholdImportant implications for cost-effectiveness of CTCPolyp Size Threshold% Requiring colonoscopy10mm7.58mm13.56mm29.7Pickhardt et al, NEJM 2003第二十二页，共二十七页。CT虚拟结肠镜23CT Colono

16、graphy: Additional Evidence A number of other studies have demonstrated a high level of sensitivity for cancer and large polyps Findings from the recently completed multi-center ACRIN trial reportedly are similar to those of Pickhardt et al Some results from this trial have been reported at medical

17、meetings, but have not yet been published Manuscript has been prepared and is currently under review第二十三页，共二十七页。CT虚拟结肠镜24CT Colonography: Limitations Requires full bowel prep (which most patients find to be the most unpleasant aspect of colonoscopy)Colonoscopy is required if abnormalities detected,

18、sometimes necessitating a second bowel prepExtra-colonic findings can lead to additional testing (may have both positive and negative implications)Controversy regarding management of small polyps, sensitivity for “flat polyps”Radiation exposureSteep learning curve for radiologistsLimited availabilit

19、y to high quality exams in many parts of the countryMost insurers do not currently cover CTC as a screening modality 第二十四页，共二十七页。CT虚拟结肠镜252008 CRC Guidelines continue to emphasize options because: Evidence does not yet support any single test as “best”Uncertainty exists about performance of differen

20、t screening methods with regard to benefits, harms, and costs (especially on programmatic basis) Uptake of screening remains disappointingly low Individuals differ in their preferences for one test or another Primary care physicians differ in their ability to offer, explain, or refer patients to all options equally Access is uneven geographically, and in terms of test charges and insurance coverage第二十五页，共二十七页。CT虚拟结肠镜26If tests that can prevent CRC are preferred, why n