MRI gives SWIFT preoperative indication of jawbone disease in oral cancer
The often difficult task of detecting whether advanced squamous cell carcinoma (SCC) that arises in the oral cavity has invaded the mandible may be made easier with an MRI technique known as sweep imaging with Fourier transform, or SWIFT.
Current imaging modes are often suboptimal for detecting jawbone invasion by SCC. A more accurate determination of such invasion before surgery might allow the surgeon to contain the cancerous cells, prevent unnecessary removal of the mandible, and aid in planning for reconstruction. Unlike conventional imaging techniques, SWIFT offers delineated assessment of cortical and medullary bone.
In order to better visualize the structural changes of intramandibular anatomy during invasion, researchers explored the SWIFT method of MRI for mandibular invasion by SCC in a preliminary study. They obtained two specimens per patient from a set of patients with oral carcinoma who had undergone segmental mandibulectomy. Both specimens had histopathologic evidence of mandibular invasion with tumor. Images obtained by SWIFT were compared with histologic sections of specimens.
A high degree of correlation was found between the SWIFT MRI images and the histopathologic findings. The three-dimensional SWIFT images were of sufficient resolution (156 to 273 micrometers) to depict tumor invasion of cortical and medullary bone.
The authors concluded in Archives of Otolaryngology—Head & Neck Surgery (2011;137:916-919) that these preliminary results demonstrate that the SWIFT imaging technique has the capacity to show fine details of intramandibular anatomy. In addition, the correlations between the histologic and MR images of the two sets of specimens clearly show malignant invasion not previously exhibited with MRI techniques.