Polyp Candidate

The polyp candidates thus detected include a large number of false-positive findings. Studies have shown that prominent folds and stool are major sources of false-positives in CAD (Yoshida et al. 2002a Yoshida et al. 2002b). Various methods characterising false-positives have been developed... 

The first paradigm, CAD as a first reader, is attractive because it allows readers to focus only on a small number of polyp candidates indicated by CAD for successive identification of the true polyps thus this paradigm can drastically reduce interpretation time. This paradigm can possibly be used for separating out negative CTC cases even before radiologists read the cases (Evancho 2002). However, such a separation is likely to come with an increased number of missed abnormalities, because there is always a trade-offbetween sensitivity and specificity... 

Nappi J, Frimmel H, Yoshida H (2005a) Virtual endoscopic visualization of the colon by shape-scale signatures. IEEE Trans Inf Technol Biomed 9 120-131 Nappi J, Okamura A, Frimmel H et al (2005b) Region-based supine-prone correspondence for the reduction of falsepositive CAD polyp candidates in CT colonography. Acad Radiol 12 695-707... 

To date, most of the CAD schemes developed in academia and in industry comprise of the following four fundamental steps (1) extraction of the colonic wall from the CTC images, (2) detection of polyp candidates in the extracted colon, (3) characterization of false positives, and (4) discrimination between false positives and polyps. A brief descrip-... 

Anti-neoplastic activity of UDCA was demonstrated first in the context of ulcerative colitis-associated colorectal carcinogenesis. Subsequently, encouraging (but not definitive) results have been obtained in clinical trials of UDCA for prevention of sporadic colorectal adenoma recurrence, which should prompt further evaluation of UDCA for polyp prevention, particularly given its excellent safety profile compared with other candidate chemoprevention agents such as the nonsteroidal anti-inflammatory drugs. 

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