The aim of this study was to compare the clinical usefulness of ultrasmall superparamagnetic iron oxide (USPIO) MR contrast media (Sinerem, Guerbet Laboratories, Aulnay-sous-Bois, France) with precontrast MRI in the diagnosis of metastatic lymph nodes in patients with head and neck squamous cell carcinoma, using histology as gold standard. Eighty-one previously untreated patients were enrolled in a multicenter phase-III clinical trial. All patients had a noncontrast MR, a Sinerem MR, and surgery within a period of 15 days. The MR exams were analyzed both on site and by two independent radiologists (centralized readers). Correlation between histology and imaging was done per lymph node groups, and per individual lymph nodes when the short axis was > or = 10 mm. For individual lymph nodes, Sinerem MR showed a high sensitivity (> or = 88%) and specificity (> or = 77%). For lymph node groups, the sensitivity was > or = 59% and specificity > or = 81%. False-positive results were partially due to inflammatory nodes; false-negative results from the presence of undetected micrometastases. Errors of interpretation were also related to motion and/or susceptibility artifacts and problems of zone assignment. Sinerem MR had a negative predictive value (NPV) > or = 90% and a positive predictive value (PPV) > or = 51%. The specificity and PPV of Sinerem MR were better than those of precontrast MR. Precontrast MR showed an unexpectedly high sensitivity and NPV which were not increased with Sinerem MR. The potential contribution of Sinerem MR still remains limited by technical problems regarding motion and susceptibility artifacts and spatial resolution. It is also noteworthy that logistical problems, which could reduce the practical value of Sinerem MR, will be minimized in the future since Sinerem MR alone performed as good as the combination of precontrast and Sinerem MR.
Mostly, parapharyngeal masses are represented by salivary gland tumors (40%-50%). The second most common tumors in the parapharyngeal space are neurogenic tumors (17%-25%). Paragangliomas are the third group of common parapharyngeal lesions (10%-15%). A mixed group of lesions like branchial cleft cysts, lymph nodes and hematogenic tumors represent the remaining part of the parapharyngeal masses (10%-33%). Most of the lesions (80%) are benign. Because of the magnetic response imaging a reliable preoperative diagnosis is possible in more than 80% of the tumors. The surgical management may also be influenced by the location of the tumor shown in the magnetic resonance imaging.
Our experience with the use of the CAD-system in daily routine showed that CAD analysis can easily be integrated into a preexisting mammography unit. However, the diagnostic benefit is not yet clearly established. Since the rate of false negative marks by the CAD-system Image Checker is still high, the results of CAD analysis must be checked and corrected by an observer well experienced in mammography reading.
Carcinomas of the oral cavity, oropharynx and hypopharynx represents 5% of all malignant neoplasms. The vast majority, over 90%, are squamous cell carcinomas; less common are lymphomas and tumors of the minor salivary glands. In general, the clinical findings already suggest the presence of a tumor. Therefore, the role of imaging is precise tumor localisation and staging of the malignancy. CT is still the gold standard, although MRI is gaining more importance. We present the CT appearance of most frequent malignancies of the oral cavity, oro- and hypopharynx, discussing briefly the pertinent anatomy.
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