Morphometric Study of a Huge Elongated Styloid Process.

An elongated styloid process (ESP) is present in 4% of the general population. It is sometimes found incidentally by panoramic radiography or computed tomography in the clinical setting. Few detailed morphometric studies of this phenomenon have been performed, however, especially regarding its histologic aspects. During anatomic dissection of a 71-year-old man who had died from cardiac failure and whose body had been donated to our department for medical student training, an ESP was found while disconnecting the stylohyoid muscle from the hyoid bone. It measured 88 mm in length. After resection, the ESP was examined using computed tomography and was assessed histologically. The results showed that it consisted of bone and cartilage. It was composed mainly of three types of cartilage with a beaded appearance. Masson trichrome staining revealed scattered collagenous fibers around the cartilage. Although ESP is not uncommon in the clinical setting, this huge ESP found during a dissection course and its detailed histologic investigation were considered sufficiently valuable to be reported.