More articles from HEAD & NECK
- Comparison of Enhancement of the Vestibular Perilymph between Variable and Constant Flip Angle–Delayed 3D-FLAIR Sequences in Menière Disease
The authors compared the degree of perilymphatic enhancement and the detection rate of endolymphatic hydrops using constant and variable flip angle sequences in 16 patients with 3T MR imaging. Both for symptomatic and asymptomatic ears, the median signal intensity ratio was significantly higher with the constant flip angle than with the heavily-T2 variable flip angle. Cochlear blood-labyrinth barrier impairment was observed in 4/18 symptomatic ears with the heavily-T2 variable flip angle versus 8/19 with constant flip angle sequences. They conclude that 3D-FLAIR constant flip angle sequences provide a higher signal intensity ratio and are superior to heavily-T2 variable flip angle sequences in reliably evaluating the cochlear blood-labyrinth barrier impairment.
- Early Detection of Cancer: Evaluation of MR Imaging Grading Systems in Patients with Suspected Nasopharyngeal Carcinoma
Dedicated nasopharyngeal MR imaging before (plain scan system) and after intravenous contrast administration (current and modified systems) was reviewed in patients from a nasopharyngeal carcinoma-endemic region, comprising 383 patients with suspected disease without nasopharyngeal carcinoma and 383 patients with nasopharyngeal carcinoma. The modified and plain scan systems refined primary tumor criteria, added a nodal assessment, and expanded the system from 4 to 5 grades. The current, modified, and plain scan MR imaging systems yielded sensitivities of 99.74%, 97.91%, and 97.65%, respectively, and specificities of 63.45%, 89.56%, and 86.42%, respectively. The modified system yielded significantly better performance than the current and plain systems. In conclusion, the authors propose a modified MR imaging grading system that improves diagnostic performance for nasopharyngeal carcinoma detection. Contrast was not valuable for low MR imaging grades, and the plain scan shows potential for use in screening programs.
- 4D–Dynamic Contrast-Enhanced MRI for Preoperative Localization in Patients with Primary Hyperparathyroidism
The authors tested the hypothesis that recently introduced 4D dynamic contrast-enhanced MR imaging with high spatial and temporal resolution has equivalent accuracy to 4D-CT for preoperative gland localization in primary hyperparathyroidism. Fifty-four patients met the inclusion criteria: 37 had single-gland disease, and 17, multigland disease—9 with double-gland hyperplasia; 3 with 3-gland hyperplasia, and 5 with 4-gland hyperplasia. For single-gland disease, the gland was correctly located in 92% of patients, with correct identification of the side in 100% and the quadrant in 92%. For multigland disease, the glands were correctly located in 74% of patients, with correct identification of the side in 74% and the quadrant in 77%. The high spatial and temporal resolution 4D dynamic contrast-enhanced MR imaging provides excellent diagnostic performance for preoperative localization in primary hyperparathyroidism.