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The use of 3D surface fitting for robust polyp detection and classification in CT colonography 总被引:3,自引:0,他引:3
In this paper we describe the development of a computationally efficient computer-aided detection (CAD) algorithm based on the evaluation of the surface morphology that is employed for the detection of colonic polyps in computed tomography (CT) colonography. Initial polyp candidate voxels were detected using the surface normal intersection values. These candidate voxels were clustered using the normal direction, convexity test, region growing and Gaussian distribution. The local colonic surface was classified as polyp or fold using a feature normalized nearest neighborhood classifier. The main merit of this paper is the methodology applied to select the robust features derived from the colon surface that have a high discriminative power for polyp/fold classification. The devised polyp detection scheme entails a low computational overhead (typically takes 2.20 min per dataset) and shows 100% sensitivity for phantom polyps greater than 5 mm. It also shows 100% sensitivity for real polyps larger than 10 mm and 91.67% sensitivity for polyps between 5 to 10 mm with an average of 4.5 false positives per dataset. The experimental data indicates that the proposed CAD polyp detection scheme outperforms other techniques that identify the polyps using features that sample the colon surface curvature especially when applied to low-dose datasets. 相似文献
4.
Serous papillary carcinoma is an aggressive tumor. Point mutations in the p53 suppressor gene might explain in part the rapid growth of this malignant tumor and its unfavorable outcome. The aims of this study were to evaluate the behavior of serous papillary carcinoma developing in endometrial polyps and to assess the p53 protein overexpression. Patients included in this study were treated in our institution between 1982 and 2003. All clinical and pathological materials were examined. A p53 protein immunohistochemical analysis was performed on paraffin-embedded tissues. Thirteen serous papillary carcinomas arising from benign polyps of the endometrium were identified. The patients' age averaged 73 years. All patients were treated surgically. After an average follow-up of 22 months, 54% of the patients were dead or alive with disease. Of 10 serous papillary carcinomas, 8 (80%) for which paraffin blocks were available overexpressed the p53 protein. A serous papillary carcinoma arising from benign polyps of the endometrium remains a malignant neoplasia with an unfavorable outcome even if the primary tumor is limited to the polyp. The high rate of protein p53 overexpression suggests that a p53 gene mutation occurs early in the disease and might explain the rapid growth of the tumor. 相似文献
5.
Gene profiling reveals increased expression of uteroglobin and other anti-inflammatory genes in glucocorticoid-treated nasal polyps 总被引:3,自引:0,他引:3
Benson M Carlsson L Adner M Jernås M Rudemo M Sjögren A Svensson PA Uddman R Cardell LO 《The Journal of allergy and clinical immunology》2004,113(6):58-1143
BACKGROUND: Treatment with local glucocorticoids (GCs) decreases symptoms and the size of nasal polyps. This might depend on the downregulation of proinflammatory genes, as well as the upregulation of anti-inflammatory genes. OBJECTIVE: We sought to identify GC-regulated anti-inflammatory genes in nasal polyps. METHODS: Affymetrix DNA microarrays were used to analyze the expression of 22,283 genes in 4 nasal polyps before and after local treatment with fluticasone (400 microg/d). Expression of uteroglobin and mammaglobin B was analyzed with real-time PCR in 6 nasal polyps and in nasal biopsy specimens from 6 healthy control subjects. RESULTS: Two hundred three genes had changed in expression in treated polyps, and 139 had known functions: 54 genes were downregulated, and 85 were upregulated. Genes associated with inflammation constituted the largest single functional group. These genes affected key steps in inflammation (eg, immunoglobulin production; antigen processing and presentation; and the chemoattraction and activation of granulocytes, T cells, and B cells). Several proinflammatory genes were downregulated. In contrast, some anti-inflammatory genes were upregulated. The gene that increased most in terms of expression was uteroglobin. This was confirmed with real-time PCR. By contrast, expression of uteroglobin was lower in untreated polyps than in healthy nasal mucosa. Immunohistochemical investigation showed staining of uteroglobin in the epithelium and in seromucous glands in control subjects and in nasal polyps. CONCLUSION: Upregulation of anti-inflammatory genes, such as uteroglobin, might contribute to the effects of local treatment with GCs in nasal polyps. 相似文献
6.
Adult intussusception secondary to inflammatory polyp occurs rarely. Imaging of intussusception on ultrasound, CT and MRI
has been previously described. In this report we describe a case of an adult intussusception secondary to inflammatory fibroid
polyp. Both the lead point (inflammatory fibroid polyp) and intussusception were depicted on multiplanar MR images. Findings
on MRI were confirmed at surgery and histopathological examination.
Received: 11 January 2000; Revised: 3 May 2000; Accepted: 4 May 2000 相似文献
7.
Vito D Corleto Cristiano Pagnini Maria Sofia Cattaruzza Ermira Zykaj Emilio Di Giulio Giovanna Margagnoni Emanuela Pilozzi Giancarlo D��Ambra Antonietta Lamazza Enrico Fiori Mario Ferri Luigi Masoni Vincenzo Ziparo Bruno Annibale Gianfranco Delle Fave 《World journal of gastroenterology : WJG》2012,18(45):6614-6619
AIM: To compare the site, age and gender of cases of colorectal cancer (CRC) and polyps in a single referral center in Rome, Italy, during two periods.METHODS: CRC data were collected from surgery/pathology registers, and polyp data from colonoscopy reports. Patients who met the criteria for familial adenomatous polyposis, hereditary non-polyposis colorectal cancer syndrome or inflammatory bowel disease were excluded from the study. Overlap of patients between the two groups (cancers and polyps) was carefully avoided. The χ2 statistical test and a regression analysis were performed.RESULTS: Data from a total of 768 patients (352 and 416 patients, respectively, in periods A and B) who underwent surgery for cancer were collected. During the same time periods, a total of 1693 polyps were analyzed from 978 patients with complete colonoscopies (428 polyps from 273 patients during period A and 1265 polyps from 705 patients during period B). A proximal shift in cancer occurred during the latter years for both sexes, but particularly in males. Proximal cancer increased > 3-fold in period B compared to period A in males [odds ratio (OR) 3.31, 95%CI: 2.00-5.47; P < 0.0001). A similar proximal shift was observed for polyps, particularly in males (OR 1.87, 95%CI: 1.23-2.87; P < 0.0038), but also in females (OR 1.62, 95%CI: 0.96-2.73; P < 0.07).CONCLUSION: The prevalence of proximal proliferative colonic lesions seems to have increased over the last decade, particularly in males. 相似文献
8.
《Gastroenterologia y hepatologia》2022,45(6):440-449
Background and study aimsData from Japanese series show that surface morphology of laterally spreading tumors (LST) in the colon identifies lesions with different incidence and pattern of submucosal invasion. Such data from western countries are scarce. We compared clinical and histological features of LST in a western country and an eastern country, with special interest on mucosal invasiveness of LST, and investigated the effect of clinical factors on invasiveness in both countries.Patients and methodsPatients with LST lesions ≥20 mm were included from a multicenter prospective registry in Spain and from a retrospective registry from the National Cancer Center Hospital East, Japan. The primary outcome was the presence of submucosal invasion in LST. The secondary outcome was the presence of high-risk histology, defined as high-grade dysplasia or submucosal invasion.ResultsWe evaluated 1102 patients in Spain and 663 in Japan. Morphological and histological characteristics differed. The prevalence of submucosal invasion in Japan was six-fold the prevalence in Spain (Prevalence Ratio PR = 5.66; 95%CI: 3.96, 8.08), and the prevalence of high-risk histology was 1.5 higher (PR = 1.44; 95%CI: 1.31, 1.58). Compared to the granular homogeneous type and adjusted by clinical features, granular mixed, flat elevated, and pseudo-depressed types were associated with higher odds of submucosal invasion in Japan, whereas only the pseudo-depressed type showed higher risk in Spain. Regarding high-risk histology, both granular mixed and pseudo-depressed were associated with higher odds in Japan, compared with only the granular mixed type in Spain.ConclusionThis study reveals differences in location, morphology and invasiveness of LST in an eastern and a western cohort. 相似文献
9.
Robertson DJ Greenberg ER Beach M Sandler RS Ahnen D Haile RW Burke CA Snover DC Bresalier RS McKeown-Eyssen G Mandel JS Bond JH Van Stolk RU Summers RW Rothstein R Church TR Cole BF Byers T Mott L Baron JA 《Gastroenterology》2005,129(1):34-41
BACKGROUND & AIMS: Colonoscopic polypectomy is considered effective for preventing colorectal cancer (CRC), but the incidence of cancer in patients under colonoscopic surveillance has rarely been investigated. We determined the incidence of CRC in patients under colonoscopic surveillance and examined the circumstances and risk factors for CRC and adenoma with high-grade dysplasia. METHODS: Patients were drawn from 3 adenoma chemoprevention trials. All underwent baseline colonoscopy with removal of at least one adenoma and were deemed free of remaining lesions. We identified patients subsequently diagnosed with invasive cancer or adenoma with high-grade dysplasia. The timing, location, and outcome of all cases of cancer and high-grade dysplasia identified are described and risks associated with their development explored. RESULTS: CRC was diagnosed in 19 of the 2915 patients over a mean follow-up of 3.7 years (incidence, 1.74 cancers/1000 person-years). The cancers were located in all regions of the colon; 10 were at or proximal to the hepatic flexure. Although most of the cancers (84%) were of early stage, 2 participants died of CRC. Seven patients were diagnosed with adenoma with high-grade dysplasia during follow-up. Older patients and those with a history of more adenomas were at higher risk of being diagnosed with invasive cancer or adenoma with high-grade dysplasia. CONCLUSIONS: CRC is diagnosed in a clinically important proportion of patients following complete colonoscopy and polypectomy. More precise and representative estimates of CRC incidence and death among patients undergoing surveillance examinations are needed. 相似文献
10.
目的评估黑色先端帽辅助结肠镜联合窄带光成像(narrow band imaging,NBI)技术对腺瘤/息肉检出效能的影响。方法连续纳入2016年10月—2018年10月行结肠镜检查的患者,采用随机数字表法分为黑色先端帽组和对照组,黑色端帽组采用黑色先端帽辅助结肠镜联合NBI技术,对照组采用标准白光结肠镜,比较两组的息肉检出率、腺瘤检出率等指标,并进行亚组分析。结果共1 000例患者纳入本研究(每组500例),黑色先端帽组和对照组近端结肠腺瘤检出率分别为24.2%(121/500)和17.2%(86/500),近端结肠息肉检出率分别为28.8%(144/500)和21.4%(107/500),平均腺瘤检出数分别0.41±0.94和0.26±0.68,平均息肉检出数为0.63±1.16和0.40±0.85,差异均有统计学意义(P均<0.05),但该联合技术对于远端结直肠病变的检出率相较对照组无明显优势。结论黑色先端帽辅助结肠镜联合NBI能显著提高近端结肠腺瘤和息肉等微小病变的检出效能。 相似文献