ABSTRACT
In 2008, CT colonography was approved by the American Cancer Society as a technique for screening for colorectal cancer. This approval should be considered an important step in the recognition of the technique, which although still relatively new is already changing some diagnostic algorithms. This update about CT colonography reports the quality parameters necessary for a CT colonographic study to be diagnostic and reviews the technical innovations and colonic preparation for the study. We provide a brief review of the signs and close with a discussion of the current indications for and controversies about the technique.
Subject(s)
Colonic Diseases/diagnostic imaging , Colonography, Computed Tomographic , Colonography, Computed Tomographic/methods , Colonography, Computed Tomographic/standards , Humans , SoftwareABSTRACT
BACKGROUND AND STUDY AIMS: Most natural orifice transluminal endoscopic surgery (NOTES) procedures have been performed in animal models through the anterior stomach wall, but this approach does not provide efficient access to all anatomic areas of interest. Moreover, injury of the adjacent structures has been reported when using a blind access. The aim of the current study was to assess the utility of a CT-based (CT: computed tomography) image registered navigation system in identifying safe gastrointestinal access sites for NOTES and identifying intraperitoneal structures. METHODS: A total of 30 access procedures were performed in 30 pigs: anterior gastric wall (n = 10), posterior gastric wall (n = 10), and anterior rectal wall (n = 10). Of these, 15 procedures used image registered guidance (IR-NOTES) and 15 procedures used a blind access (NOTES only). Timed abdominal exploration was performed with identification of 11 organs. The location of the endoscopic tip was tracked using an electromagnetic tracking system and was recorded for each case. Necropsy was performed immediately after the procedure. The primary outcome was the rate of complications; secondary outcome variables were number of organs identified and kinematic measurements. RESULTS: A total of 30 animals weighting a mean (± SD) of 30.2 ± 6.8 kg were included in the study. The incision point was correctly placed in 11 out of 15 animals in each group (73.3â%). The mean peritoneoscopy time and the number of properly identified organs were equivalent in the two groups. There were eight minor complications (26.7â%), two (13.3â%) in the IR-NOTES group and six (40.0â%) in the NOTES only group ( P = n.âs.). Characteristics of the endoscope tip path showed a statistically significant improvement in trajectory smoothness of motion for all organs in the IR-NOTES group. CONCLUSION: The image registered system appears to be feasible in NOTES procedures and results from this study suggest that image registered guidance might be useful for supporting navigation with an increased smoothness of motion.
Subject(s)
Abdomen/anatomy & histology , Laparoscopy/methods , Natural Orifice Endoscopic Surgery/methods , Surgery, Computer-Assisted/methods , Tomography, X-Ray Computed/methods , Animals , Female , Image Processing, Computer-Assisted , Models, Animal , Motion , Radiography, Abdominal , Rectum/surgery , Stomach/surgery , SwineABSTRACT
Rectal cancer has a high incidence in our area. The different treatment options that can be used in each case depend fundamentally on the extension of the tumor at the time of diagnosis. Thus, radiologists have a central role in the management of this disease. We discuss the optimum imaging technique for staging rectal cancer, some fundamental histological aspects, and the accepted semiology in the interpretation of different imaging studies carried out in these patients, as well as the diagnostic performance of each technique. We provide a general overview of the prognosis and different treatment options. This knowledge is very useful for radiologists participating in multidisciplinary teams and for understanding the transcendence of the information provided by image interpretation in these patients.