Role of MSCT, MRI, DWI, PET / CT, 3D-Reconstruction and Virtual Endoscopy in Detecting Colon Diseases and Colorectal Cancer

Abstract

Currently in the world there is a tendency of continuous growth in the incidence of cancer of the rectum and colon. The tendency to a continuous increase in the incidence is especially pronounced in industrialized countries. Within this re-search we have set to establish MSCT criteria for the infiltration and exophytic growth of colon cancer, to establish the capabilities of DWI and PET / CT in the diagnosis of to establish criteria for the invasion of tumor intestinal walls, to de-termine the effectiveness of chemoradiation and surgical treatment, as well as to determine the radiological criteria for recurrent tumors. Materials and Methods: MSCT colonoscopy was performed in 345 patients (240 with suspected cancer, 105 with polyps). Patients underwent standard preparation. The usual radiation dose for MSCT colonoscopy is 6–12 mGy. During screening, it is possible to re-duce the dose to 3–6 mGy ("low dose technique"). The low dose technique should be used to determine the colonoscope obstruction cause or in case performing irrigoscopy is not possible. The contrast medium is often required to envelope the pebble poop. We used standard abdominal radiography, MSCT (multispiral computed tomography), MRI (magnetic resonance imaging), DWI (diffusionweighted images). MSCT studies were carried out on 4 and 64-slice Toshiba devices. MRI examinations were performed with a field strength of 1.5T PET/CT were performed using labeled 18F-FDG (2-fluorodesoxyglucose). Results: MSCT, including MSCT endoscopy, is a highly informative method for detecting invasive colon cancer, showing sensitivity and specificity indicators approaching to 100%, that may not be extended to colon polyps’ diagnosis (76%). Use of MSCT can increase the accuracy of preoperative detection of a colon tumor, clarify the stage of the disease, detect tumor recurrence, and determine the effective-ness of radiation therapy. The sensitivity of MSCT for detecting polyps of 5–6 mm in size was 59%, with optical colonoscopy – 76%, the sensitivity of MSCT for detecting polyps >10 mm was 91%, with optical colonoscopy – 95%. The advantage of virtual colonoscopy is that it does not require complex preparation of the patient for the study and does not injure them, since this method is, in fact, variant of computed tomography. This technique is well suited for screening patients from risk groups, especially in the presence of polyps, because they often undergo malignant transformation. Conclusion: MSCT, DWI, MRI are useful in the diagnosis and definition of the metastatic focus of neoplasm. 18F-FDG PET / CT can provide prognosis information after surgical resection of colon cancer. PET / CT provides a significant advantage in improving diagnosis and therapeutic monitoring of patients, monitoring treatment responses.