Large colonic neoplasms missed by endoscopy

Endoscopy is commonly accepted as the gold standard in the evaluation of neoplastic colonic disease. The procedure is used to confirm or exclude lesions detected on barium enemas, with the assumption that the endoscopist was successful in reaching the appropriate segment of the colon. We collected 18 cases, all with proved colonic neoplasm 2-8 cm in diameter that were detected by barium enema but overlooked on initial endoscopy. All of the lesions were relatively flat with little intraluminal protuberance. Histologic examination showed malignant foci in six of 11 tumors that were resected. In two of the other seven patients, unresected lesions progressed to advanced carcinomas. This experience suggests that a repeat barium enema is indicated when endoscopy fails to detect a colonic tumor suspected on barium enema examination.     

Incidental colonic focal lesions detected by FDG PET/CT

OBJECTIVE: The aim of this study was to assess the performance of FDG PET/CT for the detection of colonic lesions, especially advanced neoplasms (villous or >10-mm adenomas, carcinomas). Because of 18F FDG accumulation in adenomatous polyps, PET using FDG can detect early premalignant colorectal lesions. MATERIALS AND METHODS: FDG PET/CT studies performed for a 1-year period in 1,716 consecutive patients with various malignant diseases, except colorectal cancer, were retrospectively reviewed. PET images obtained 1 hr after FDG injection and non-contrast CT images used for attenuation correction were fused for analysis. Of 45 patients showing intense focal colonic FDG uptake, 20 patients (with 21 foci) underwent a colonoscopic investigation, and, when necessary, polyp resection. The intensity of FDG uptake was quantified using the standardized uptake value (SUV(max)). RESULTS: The FDG colonic foci were associated with 18 colonoscopic abnormalities in 15 patients, with no colonic abnormality detected in five patients (false-positive [FP] results). Histopathologic findings revealed advanced neoplasms in 13 patients (13 villous adenomas and three carcinomas) and two cases of hyperplastic polyps. A difference in the mean SUV(max) was found between FP and true-positive colonic FDG foci but was not statistically significant (p = 0.14). CONCLUSION: Presence of a focal colonic FDG uptake incidental finding on a PET/CT scan justifies a colonoscopy to detect (pre-)malignant lesions. The fusion of PET and CT images allows an accurate localization of the lesions. PET/CT is a useful tool to differentiate pathologic from physiologic FDG uptake.     

CT evaluation of right colonic wall lesions

CT of the entire clean colon after a tap water enema with intravenous injection of contrast medium was performed in 20 patiens with a diagnosis of caecal and ascending colonic lesions at barium enema studies or colonoscopy. Histological proof was obtained by endoscopy or at surgery in all cases. Using this water technique we were able to detect the wall abnormalities and describe their CT features in relation to the histological findings. We found that asymmetric thickening of the bowel wall, an irregular and lobulated inner and outer contour and/or a focal soft tissue mass usually exceeding 2 cm from the luminal to serosal surface were very helpful findings for a malignant lesion but not the hallmark of malignancy. The CT appearance of the extraluminal part of the lesion was most helpful in differentiating between benign and malignant lesions.     

Conventional endoscopy versus virtual laryngoscopy in assessment of laryngeal lesions

Background

Virtual laryngoscopy is a non invasive computed tomography based technique that allows dynamic intra-luminal laryngeal evaluation resembling direct laryngoscopy.

Objective

The aim of this prospective study is to evaluate the accuracy, clinical value and limitation of VL in the diagnosis of laryngeal masses in comparison to conventional laryngoscopy.

Patients and methods

Forty-two (42) patients with different laryngeal lesions (VL) was performed through advantage window navigation system (GE) using volume rendering reconstruction fly and through technique to navigate the laryngeal lumen.

Results

Forty-two patients with different laryngeal pathology were examined, hoarseness of voice in 27 patients 67.5%, stridor in 17 cases 42.5%, followed by chronic cough in 11 patients 27.5%, the laryngeal lesions was 18 carcinoma 45%, 13 subglottic stenosis 32.5%, 6 polyps 15%, 2 nodules 5% and 1 papilloma 2.5%, direct laryngoscopy was performed for 40 patients and all cases were pathologically proved.

Conclusion

VL is an additive tool in conjunction with the direct laryngoscopy and easily reaches the lower limit of the lesion compared to direct laryngoscopy.     

CT evaluation of gastric lesions with three-dimensional display and interactive virtual endoscopy: comparison with conventional barium study and endoscopy

OBJECTIVE: This study was undertaken to assess the feasibility of three-dimensional (3D) CT rendering using shaded-surface display (SSD) and ray sum display and virtual endoscopic images of the stomach for simultaneous evaluation of intraluminal and extraluminal abnormalities compared with conventional upper gastrointestinal barium studies and endoscopy. SUBJECTS AND METHODS: Our prospective study consisted of 39 patients with gastric lesions (17 gastric carcinomas, nine gastric polyps, five gastric varices, five gastric submucosal tumors, one lymphoma, one case of Menetrier's disease, and one gastric erosion) detected by endoscopy and barium study. All 3D CT images were reconstructed using SSD, ray sum display, and virtual endoscopic techniques. Three-dimensional images were evaluated for ability to reveal the range and morphologic features of the gastric lesions. RESULTS: All SSD, ray sum display, and virtual endoscopic images successfully revealed five of the eight early-stage gastric carcinomas and all nine advanced-stage gastric carcinomas. Submucosal tumors were revealed on 3D CT approximately as well as on conventional endoscopy. Interactive evaluation of virtual endoscopic images and multiplanar reconstructions provided useful information regarding intraluminal and submucosal gastric involvement by gastric varices, submucosal tumor, advanced gastric carcinomas, and lymphoma. This kind of information could not be obtained by conventional endoscopy or double-contrast study. CONCLUSION: Three-dimensional CT used in conjunction with virtual CT endoscopy proved helpful in identifying gastric lesions. Also, virtual CT endoscopic images with the interactive display of multiplanar reconstructions proved useful in identifying both intraluminal and submucosal components.     

Non-neoplastic tracheal lesions: comparison between virtual CT endoscopy and fiberoptic bronchoscopy

PURPOSE: To compare virtual endoscopy of the upper airways with fiberoptic bronchoscopic examination in patients affected by non-neoplastic inflammatory disease of the trachea. MATERIALS AND METHODS: Twelve patients with non-neoplastic tracheal stenosis or with tracheo-oesophageal fistula underwent a fiberoptic endoscopy and a spiral CT examination with the following protocol: collimation/table feed/reconstruction increment 3 mm/6 mm/1 mm from the larynx to the carenabronchial septum. Images were sent to a dedicated workstation equipped with a software allowing generation of 3D reconstructions and virtual endoscopic images. Lesion features were compared in the two examinations. RESULTS: In all cases the lesions features visualized with virtual display modality were confirmed by conventional endoscopy. Measurements were easily made on the 3D MPR images while conventional endoscopy allowed only a qualitative assessment of the lesion. In no cases did virtual endoscopy provide information on the mucosa appearance. Swallowing and breathing never caused significant artifacts during the 3D post processing. CONCLUSION: Virtual bronchoscopy is a useful technique for preoperative evaluation and for the follow-up of patients with non-neoplastic inflammatory disease of the upper airways.     

喉部螺旋CT仿真内窥镜的临床应用

目的：评价CT仿真内窥镜成像在显示喉部疾病的应用价值。方法：22例喉部疾病患者包括15例喉癌，3例声带息肉，1例披裂炎症，1例咽喉后壁脓肿，以及2例声带固定，均经螺旋CT扫描，获自所有病例的仿真内窥镜成像均与纤维喉镜及手术所见对照分析。所有病例或细胞学证实。结果：CT仿真喉镜对正常解剖结构显示与纤维喉镜一致，显示病变范围优于纤维喉镜，CT仿真喉镜能从足端入路观察，但对较小病灶的显示不如纤维喉镜。结论：CT仿真喉镜能对喉部病变提供较全面的信息，因而它是纤维喉镜的一种很好的补充手段。     

Polypoid epithelial malignancies of the esophagus

Polypoid epithelial malignancies of the esophagus are rare tumors. One hundred fifty cases of epithelial malignancy of the esophagus accessioned to the Registry of Radiologic Pathology at the Armed Forces Institute of Pathology were reviewed with respect to morphologic and pathologic characteristics. Only large intraluminal polypoid epithelial masses were analyzed. Criteria used to select cases were: (1) size greater than 4 cm, (2) expansion of the esophageal lumen by the bulky tumor, and (3) absence of constriction or wall infiltration. Twenty-two lesions met these criteria (15 spindle cell carcinomas, two carcinosarcomas, three squamous cell carcinomas, and two oat cell carcinomas). When an esophageal neoplasm is polypoid and bulky, creates a "cupola" effect, has scalloped edges, expands the lumen of the esophagus, and is pedunculated, one must consider spindle cell carcinoma as the primary diagnosis.     

胆囊息肉样病变的超声诊断

目的：分析超声显像诊断胆囊息肉样病变的价值。材料与方法：本院１９８４￣１９９５年超声诊断胆囊息肉样病变１０５例，回顾性分析其声像图特征，并与手术病理检查对照。结果：正确诊断９６例，占９１．４％，误诊９例，占８．６％。为了提高对胆囊息肉样病变的诊断准确率，本文提出应从病变部位、大小、数目、内部回声以及与胆囊壁的联系等５个方面进行分析。结论：超声显像诊断胆囊息肉样病变具有较大的临床价值。     

Radiographically undetected coracoid fractures diagnosed by sonography. Report of seven cases

Coracoid process fractures are rare and can be overlooked on routine radiographs due to the anatomical orientation of the CP and superimposition of adjacent bone structures. Early fracture detection reduces morbidity and allows for proper treatment. Sonography of the shoulder is usually performed for evaluation of peri-articular soft tissues. To the best of our knowledge, sonographic diagnosis of CP fracture has not been reported in the literature. We present a retrospective review of seven cases of sonographically detected coracoid fractures which were undiagnosed at previous standard radiographs. The US diagnosis was confirmed in three subjects, two with CT and in one patient with axillary view radiograph.     

Distribution of colonic polyps: increased incidence of proximal lesions in older patients

Several recent studies have shown a proximal shift in the distribution of colonic carcinoma compared to older studies. Because of the association between polyps and cancer, the authors evaluated the distribution of colonic polyps in 3,664 consecutive patients who had a colon examination over a period of 14 months. A total of 967 colorectal polyps were found in 633 patients. In all, 502 polyps (52%) were proximal to the rectosigmoid. Older patients had significantly more right-sided polyps and fewer rectosigmoid lesions. Large polyps occurred more frequently in the right colon, and this was also statistically significant. Gender has no effect on polyp distribution. The authors conclude that the importance of screening for polyps, particularly on the right side of the colon, increases with age.