The occurrence of transient severe motion during arterial phase MRI with gadoxetate disodium is 12.9% and is poorly predicted on the basis of risk factors.

A markedly distended gallbladder associated with decreased wall enhancement is highly specific for gangrenous cholecystitis.

Objective:To evaluate the efficacy of computer tomography (CT)-guided core needle biopsy (CNB) in the diagnosis of deep suprahyoid lesions in patients with treated head and neck cancers. Materials and Methods: Between December, 2003 and May, 2011, 28 CT-guided CNBs were performed in 28 patients with deep suprahyoid head and neck lesions. All patients had undergone treatment for head and neck cancers. Subzygomatic, paramaxillary, and retromandibular approaches were used. The surgical results, response to treatment, and clinical follow-up were used as the diagnostic reference standards. Results: All biopsies yielded adequate specimens for definitive histological diagnoses. A specimen from a right parapharyngeal lesion showed atypia, which was deemed a false negative diagnosis. Diagnostic accuracy was 27/28 (96.4%). Two minor complications were encountered: a local hematoma and transient facial palsy. Between the 18 or 20 gauge biopsy needles, there was no statistical difference in the diagnostic results. Conclusion: CT-guided core needle biopsy, with infrequent and minor complications, is an accurate and efficient method for the histological diagnosis of deep suprahyoid lesions in post-treated head and neck cancer patients. This procedure can preclude an unnecessary surgical intervention, especially in patients with head and neck cancers.