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Table 1. Extracolonic Findings in 72 Symptomatic Patients Major ECF No. Moderate ECF No. Minor ECF No. Cardiomegaly 3 Renal stone 7 Renal cyst 15 Lymphadenopathy* 2 Renal parenchymal reduction 2 Accessory spleen 08 Hepatic mass 1 Benign-looking adenal mass 2 Bony island 06 Ileal wall thickening 1 Hepatic cyst-like mass 2 Lung calcific granuloma 05 Stone with hydronephrosis 1 Renal cyst-like mass 1 Bone cyst 04 Renal solid mass 1 GB stone 1 Hepatic cyst 03 CBD stone 1 Injection granuloma 01 Lymphadenopathy 1 Mild scoliosis 01 Spinal stenosis 1 Old fracture 01 Lung consolidation 1 Peripheral emphysema 01 Fatty liver 01 Focal splenic calcification 01 Focal fibrotic band of lung 01 Retroaortic left renal vein 01 Benign adrenal mass 01 Focal hepatic calcification 01 Calcified lymph node 01 IUD 01 Hiatal hernia 01 Note. ECF, extracolonic finding; No., number of patient *Associated with suspected malignancy Associated with suspected imflammatory bowel disease 142
Fig. 2. Symptomatic 73-year old man with moderate important finding in CT colonography. Non contrast axial CT scan shows calcified stone density (arrow) in distal CBD. A B Fig. 1. Symptomatic 76-year old man with major important finding in CT colonography. A. Non contrast axial CT scan shows about 2 cm sized ill-defined low density nodule (arrow) in caudate lobe of liver, possible hepatic metastasis. Attenuation measured about 54 HU. B. Non contrast axial CT scan shows segmental wall thickening at ascending colon, representing cancer. Note also about 17mm sized well-defined low density lesion in left kidney. Attenuation measured about 9 HU, suggesting simple cyst. 143
Fig. 3. Asymptomatic 72-year old man with minor importance finding in CT colonography. Non contrast axial CT scan shows about two round cystic lesions (arrows) in right kidney. Attenuation measured about 8 10 HU, suggesting simple cyst. Table 2. Extracolonic Findings in 63 Asymptomatic Patients Major ECF No. Moderate ECF No. Minor ECF No. Cardiomegaly 2 GB stone 2 Bony island 9 Renal stone 2 Hepatic cyst 7 Lung consolication 1 Renal cyst 7 Chronic liver disease 1 Accessory spleen 7 Undescented testis 1 Focal hepatic calcification 3 Focal renal calcification 2 Focal splenic calcification 2 Subsegmental atelectasis 2 Lung calcific granuloma 2 Pleural thickening 2 Ovarian cyst 1 Splenic cyst 1 IUD 1 Schmor s nodule 1 Fatty liver 1 Nephrectomy state 1 Spinal hemangioma 1 Retroaortic left renal vein 1 Note. ECF, extracolonic finding; No., number of patient; IUD, intrauterine device 144
Table 3. Extracolonic Findings at CT Colonography According to the Clinical Importance Clinical Importance of Extracolonic Findings Any Major+ moderate Major important Moderate important Minor important Findings important Patients Patients Lesions Patients Lesions Patients Lesions Patients Symptomatic 49/72 8/72 9/82 17/72 19/82 39/72 54/82 22/72 Patients (68.1%) (11.1%) (11.0%) (23.6%) (23.2%) (54.2%) (65.9%) (30.6%) Asymptomatic 38/63 2/63 2/60 7/63 7/60 35/63 51/60 8/63 Patients (60.3%) (3.2%) (3.3%) (11.1%) (11.7 %) (55.6%) (85%) (12.7%) p-value 0.35 0.1 0.06 0.7 0.01 145
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Extracolonic Findings of CT Colonography: Frequency Analysis between Symptomatic and Asymptomatic Patients Hyun Pyo Hong, M.D., Hyon Joo Kwag, M.D., Seung Kwon Kim, M.D. 1 Department of Radiology, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea Purpose: To perform a frequency analysis of the extracolonic findings (ECF) of the CT colonography between symptomatic and asymptomatic patients. Materials and Methods: Seventy-two consecutive symptomatic patients and sixty-three consecutive asymptomatic patients who underwent CT colonography were enrolled in this study. Non-contrast enhanced axial images were reviewed retrospectively to identify the ECF and classified them as major, moderate or minor important findings according to their potential clinical importance. The frequencies of each classification and ECF were analyzed and compared between two groups (symptomatic and asymptomatic). Results: Eighty-two ECF were identified in 49 (68.1%) of the 72 symptomatic patients. The findings were classified as follows: major (8/49, 11.1%), moderate (17/49, 23.6%), minor (39/49, 54.2%). Sixty ECF were detected in 38 (60.3%) of the 63 asymptomatic patients. The findings were classified as follows: major (2/38, 3.2%), moderate (7/38, 11.1%), minor finding (35/63, 55.6%). No statistically significant differences were found between the two groups (p > 0.05) for the overall ECF frequency. However, a significantly higher frequency of major or moderate ECF was observed in symptomatic patients (30.6%) compared to asymptomatic patients (12.7%) (p < 0.05). Conclusion: The overall ECF frequency was similar between symptomatic and asymptomatic patients; however, the frequency of clinically important ECF (major or moderate) was higher in symptomatic patients, compared to asymptomatic patients. This result suggests that the major or moderate ECF required a further work up or treatment in symptomatic patients. Index words : Colonography, Computed tomographic Incidental findings Mass screening Tomography, X-Ray Computed Address reprint requests to : Seung Kwon Kim, M.D., Department of Radiology, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, 108, Pyung-Dong, Jongro-ku, Seoul 110-746, Korea Tel. 82-2-2001-2336 Fax. 82-2-2001-1030 E-mail: radi@lycos.co.kr 147