Magnetic resonance imaging--guided fine-needle aspiration biopsies of retropharyngeal lesions.

OBJECTIVE: The retropharyngeal space is a deep neck space susceptible to a host of disease processes. Surgical access to this space is technically difficult and associated with potential morbidity. An image-guided fine-needle aspiration (FNA) biopsy, if proven accurate and safe, would be of great benefit as an alternative diagnostic approach to this space. This study reports on the use of magnetic resonance imaging (MRI)--guided FNA for diagnostic evaluation of retropharyngeal lesions. Technical details of needle systems, approach to this space, and reliability of this method are described.

STUDY DESIGN: This is a prospective study of 14 patients with retropharyngeal lesions who underwent MRI-guided FNA biopsy at the University of California at Los Angeles Center for the Health Sciences between October 1989 and October 1998.

METHODS: A 0.2-tesla open magnet was used to obtain magnetic resonance images of each retropharyngeal lesion. After standard skin preparation a coaxial needle system was used to reach and sample the lesion. In most instances, the specimen was immediately stained and examined by a cytopathologist for adequacy before removing the patient from the scanner.

RESULTS: Eleven of 14 (78%) patients had diagnostic aspirations; only 2 of these 11 patients required additional surgical biopsy for more specific histological characterization of their lesions before definitive treatment recommendations were given. All aspiration procedures were well tolerated and without any complications.

CONCLUSION: We have demonstrated that MRI-guided approach to the retropharynx is feasible, safe, and sensitive enough to obviate the need for open biopsies in a large percentage of patients.