Background and purpose: Small oral cavity tumors are an imaging challenge. Intimate apposition of vestibular oral mucosa to the alveolar mucosa makes tumor assessment difficult. In CT imaging, the "puffed cheek" method has been used to separate surfaces, though this is not feasible with long MR imaging sequences. We implemented placement of 2 × 2 inch (6.45 cm) gauze into the oral vestibule before the MR imaging examination, to determine whether this might improve tumor visualization.
Materials and methods: MR imaging examinations of all T1 oral malignant tumors treated at University of California, San Francisco, by the Oral and Maxillofacial Department were reviewed by 2 neuroradiologists. Nine patients were included in the final analysis. Six patients were imaged by using a standard protocol. Three patients were imaged with gauze placement. The radiologists evaluated the MR images, assessing whether they could see the tumor and then fully delineate it and its thickness.
Results: Fisher exact analysis was performed on questions 1, 2, and 4 with the following results: P value = .048, Can you see the tumor? P value = .012, Can you fully delineate? P value of .012, How confident are you? MR imaging examinations with gauze clearly delineated the tumor with the tumor thickness measurable. MR imaging examinations without gauze did not clearly show the tumor or its thickness. Confidence of interpretation of the findings was also increased when gauze was used.
Conclusions: A 2 × 2 inch (6.45 cm) rolled gauze in the oral vestibule significantly improved tumor localization and delineation at MR imaging. This technique is simple and provides superior preoperative imaging evaluation and treatment planning of small oral cavity tumors.