[The clinical usefulness of helical CT multiplanar reformation, three-dimensional reconstruction and virtual laryngoscopy in laryngeal and hypopharyngeal carcinomas].

OBJECTIVE

To evaluate the clinical applications of helical CT multiplanar reformation (MPR), three-dimensional reconstruction (3D) and virtual laryngoscopy (CTVL) in laryngeal and hypopharyngeal carcinoma.

METHODS

Axial helical CT scan was performed in 24 patients with laryngeal or hypopharyngeal carcinoma, meanwhile MPR, 3D and CTVL were performed on each patient. The results were compared with the fiberoptic laryngoscopic and surgical findings.

RESULTS

Axial helical CT combined with MPR images, the accuracy of preoperative tumor staging and detection of metastatic lymph nodes were both 96%. In 25% of the cases, MPR was more informative than axial images about the extent of tumor invasion. The 3D image three-dimensionally displayed the extent of tumor invasion, and its relation to blood vessels and airway. On CTVL, the location, size and extent of intraluminal tumors of the larynx and hypopharynx when observed from above corresponded well with those observed under laryngoscope. In 4 patients, CTVL observed from below, demonstrated the relationship between the tumor and vocal cords and anterior commissure inaccessible to fiberoptic laryngoscopy.

CONCLUSION

Helical CT axial scanning combined with MPR, 3D and CTVL images, can provide more comprehensive information about laryngeal and hypopharyngeal carcinoma.