Magnetic resonance navigation for head and neck lesions.

OBJECTIVE

Review applications of interventional magnetic resonance imaging and describe methods, procedures, and additional instrumentation for the magnetic resonance "operating theater." Describe advantages of magnetic resonance navigation for biopsies of head and neck tumors.

STUDY

DESIGN

Patients with palpable and nonpalpable head and neck and cranial base tumors were recruited into the study. Patients underwent magnetic resonance-guided biopsy. Retrospective analysis of 21 patients was conducted.

METHODS

0.5 Tesla superconducting open magnetic resonance imaging was used for navigation of the biopsy needle. Patient records and magnetic resonance images were reviewed. The type, size, and location of the lesions were tabulated. Type of anesthesia and monitoring method were analyzed. The histopathologic correlation was conducted in patients who required further surgeries or open surgical biopsies.

RESULTS

Twenty-two biopsies were carried out in the magnetic resonance suite. One patient required general anesthesia and the other biopsies were conducted under intravenous sedation. There was only one case of nonconcurrence in a patient with Wegener's granulomatosis of the posterior orbit. Overall, a 92% concurrence rate between image-directed fine-needle aspiration, open biopsy, and surgical therapy was encountered. No complications occurred.

CONCLUSIONS

The use of interventional magnetic resonance imaging to assist with fine-needle aspiration core biopsy has made the biopsy procedure safer and more accurate. Potentially morbid and disfiguring surgeries have been avoided in some patients. Deeper lesions have been more easily approached, as the needle for biopsy is under constant magnetic resonance guidance. Improved visualization for critical structures allows safer performance of biopsies. The primary difficulties of open magnetic resonance imaging relate to the need for nonferromagnetic instrumentation and equipment and their high costs. An inverse relationship exists between the imaging quality and the "dead time" required to acquire images.