Stomach Computerized Tomography indications, technique, examples VUH SK Radiology and nuclear medicine center Radiologist Dileta Rutkauskaitė
Stomach Computerized Tomography gastroente rologist Oncologist endoscopist surgeon radiologist
Stomach Computerized Tomography appropriate preparation technique of examination examples of pathology
Indications for stomach CT Preoperative evaluaton with pathologicaly proven gastric cancers Evaluation of the disease progresion/response to chemotherapy Detection and differentiation of submucosal lesions H. S. Kim, H. Y. Han et Preoperative evaluation of gastric cancer: value of spiral CT during gastric arteriography (CTGA) ; Abdom Imaging 26:123 130 (2001)
Anamnesis Patient anamnesis Previous gastric operations Endoscopic results Histopathological results
Stomach CT- preparation Fasting for 6-8 hour. Current Role of CT in Imaging of the Stomach Karen M. Horton, MD Elliot K. Fishman, MD RadioGraphics
Stomach CT- preparation We use pure water as an oral contrast agent (~800-1000 ml) - well tolerated - good distention of the stomach wall - allows good visualization of the enhancing wall Current Role of CT in Imaging of the Stomach1 Karen M. Horton, MD Elliot K. Fishman, MD RadioGraphics
Stomach CT- preparation For imaging of the stomach, adequate distention is essential. If the entire stomach is not well distended, disease may be overlooked or the collapsed gastric wall may mimic disease.
Stomach CTpatient positioning Supine position Right lateral decubitus position Patient are positioned according to the presumed location of the lesion seen at endoscopy
Stomach CTscanning Scanning - unenhanced scan (to evaluate gastric distention) - enhanced scan after i/v c/m injection: 2 phases: - Late arterial ph. (35-40s), - Portal venous ph. (70 s) - Delayed ph. (150 s). Current Role of CT in Imaging of the Stomach Karen M. Horton, MD Elliot K. Fishman, MD RadioGraphics
Stomach CT Normal gastric wall cearly visible as two or three layers; - mucosa (intensively enhancing layer) - submucosa (low density layer) - musculiaris propria and serosa (enhancing layer) Normaly no more 5 mm in thickness
Gastric pathology
Gastric adenoca CT signs: - Enhacement changes in the wall - Local or diffuse wall thickening - Infiltration into surrounding structures - liver, l/n mts
CT Criteria for T and N Staging of Gastric Cancer Stage T stage CT Criteria T1 Neoplasm shows focal thickening of inner layer, is almost well enhanced, and has visible low-attenuation-strip outer layer of gastric wall and clear fat plane around tumor T2 T3 T4 Neoplasm shows focal or diffuse thickening of gastric wall with transmural involvement, is almost well enhanced, and has smooth outer wall border and clear fat plane around tumor Transmural tumor with irregular or nodular outer border and/or perigastric fat infiltration Obliteration of fat plane between gastric tumor and adjacent organ or invasion of adjacent organ N stage N0 N1 N2 N3 No regional lymph node metastases Metastases in 1 6 regional lymph nodes Metastases in 7 15 regional lymph nodes Metastases in 15 regional lymph nodes Greene FL, Page DL, Fleming ID, et al, eds. AJCC manual of staging of cancer. 6th ed. New York, NY: Springer-Verlag, 2002
Gastric adenoca in situ
Early gastric cancer - T1
Gastric adenoca T2
Gastric adenoca T3
Gastric adenoca T4 N1M1
Gastric infiltrative adenoca
Gastric lymphoma Diffuse or segmental wall infiltration Usualy we see enlarged l/n Ct feature can be like adenoca
Gastric lymphoma
Gastric GIST
Gastric GIST During abdominal echoscopy was suspected panceatic lesion
Gastric ulcerated GIST in antrum
Gastric endocrinal tumors Carcinoid in gastric body mostly like small polyps mostly intensively enhancing
Gastric neuroendocrine Ca pt2n1 Histo carcinoid Transmural c/m enhancement Enlarged, round of shape, enhancing l/n
Intramural pseudocyst into gastric wall
Gastric antrum lipoma
Endoscopy findings gastric fundus submucosal lesion CT - polysplenism
Gastric diverticulum
Conclusions - Correct patient preparation for gastric CT examination is essential - gives a lot of information about the changes in gastric wall - The knowledge in characteristics of CT findings in normal gastric wall and pathological changes is crucial for the accurate diagnosis, treatment choice and planing
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