Endoscopic endonasal nasopharyngectomy: tensor veli palatine muscle as a landmark for the parapharyngeal internal carotid artery.

BACKGROUND: Endoscopic endonasal nasopharyngectomy(EEN) can be a promising option for select patients with recurrent nasopharyngeal carcinoma, but serious complications can occur in terms of parapharyngeal internal carotid artery (PPICA) injury. Several landmarks have been proposed for locating the PPICA. In this study, we investigated the spatial relationship between the tensor veli palatini (TVP) muscle and the PPICA in a cadaveric model. METHODS: Seven fresh cadaver heads were available for anatomic study. Eustachian tube and the levator veli palatine (LVP) muscle were partially sacrificed or truncated to maximize the surgical field, and the TVP muscle was carefully preserved. Complete dissection was defined as when the PPICA could be visualized. We then measured the distance between the posterior margin of the TVP muscle and PPICA (z-axis), and the distance from the midline of the nasopharynx to the PPICA (x-axis). RESULTS: Thirteen sides of the PPICA were successfully identified. The mean distance between the posterior margin of the TVP to the PPICA (z) was 20.3 mm (range, 12 to 28 mm), and the mean distance between the midline of the nasopharynx to the PPICA (x) was 19.6 mm (range, 15 to 24 mm). CONCLUSION: The PPICA was located in the same sagittal plane as the TVP muscle during dissection posteriorly. The PPICA appeared to lie around 2 cm laterally from the midline at around 2 cm in depth from the posterior margin of the TVP muscle. However, the exact position of the PPICA should be assessed using preoperative magnetic resonance imaging and intraoperative image-guided systems.

Development of Taiwan Smell Identification Test: a quick office-based smell screening test for Taiwanese.

BACKGROUND: Objective smell tests not only identify levels of smelling ability but also provide information on changes in olfaction after treatment. Odor identification is strongly socially and culturally dependent; therefore, the odorants used in a smell identification test should be familiar to the test population. We developed this smell test for Taiwanese populations with two aims: the test odors should be familiar to Taiwanese and the test should be easily and quickly administered in a busy clinic. METHODS: Additives that are familiar to Taiwanese people were selected for this smell identification test. Subsequently, the test was validated with the traditional Chinese version of the University of Pennsylvania Smell Identification Test (TC-UPSIT). Finally, this Taiwan Smell Identification Test (TWSIT) was implemented in daily clinical use, and cut-off points of "normosmia," "hyposmia," and "anosmia" were established. RESULTS: A total of 1000 subjects were included in the market survey to identify commonly recognized odors. Eight odorants with identification rate greater than 95% were selected. The TWSIT is an array of multiple-choice questions to select the odor. In addition, patient also reported the strength of the odor. The full score was 48. Thirty-seven patients simultaneously received both TWSIT and TC-UPSIT, and the correlation was high (r = 0.874). Based on the testing results of an additional 187 subjects, we concluded that scores of 47-48, 15-44, and 2-12 corresponded to normosmia, hyposmia, and anosmia, respectively. Patients with scores falling in the gaps require retesting at a later time. CONCLUSION: The TWSIT is a quick, office-based, and useful odor identification tool for Taiwanese. The experience of developing a culturally specific olfaction test like the TWSIT can be applied in different countries and cultures.

En bloc resection concept for endoscopic endonasal nasopharyngectomy: surgical anatomy and outcome.

BACKGROUND: Nasopharyngeal carcinoma (NPC) patients have a 19%-56% locoregional recurrence rate after primary therapy. For those recurrent NPC (rNPC) patients, re-irradiation may cause some complications. In recent years, endoscopic endonasal nasopharyngectomy (EEN) has become a surgical option for rNPC patients. Here we introduce the concept of en bloc excision (EBE) technique for EEN, including the surgical technique and clinical outcomes. METHODS: A retrospective study was conducted covering September 2009 to May 2013, involving the collection of locoregional rNPC cases from two institutions (Kuang-Tien General Hospital (KTGH) in Taiwan and National University Health System (NUHS) in Singapore). These patients failed prior therapy and then underwent EEN. We reported the 2-year overall survival rate, the 2-year disease-free survival rate, and related complications. RESULTS: Nine patients (five from KTGH and four from NUHS) completed this study, with five, two, and two patients of recurrence tumors (rT1), rT2, and rT3, respectively. The mean age was 46.4 years (range 32-63); the mean follow-up period was 24.9 months (range 10-45). The 2-year survival rate and the 2-year disease-free rate were 100% and 80%, respectively, in five patients. No significant complications or cases of mortality occurred. CONCLUSIONS: The EBE concept of EEN is suitable for early rT1 and has relatively encouraging short-term outcomes. In selected rT2, careful EBE can be performed by expanding the surgical field. A clear view of the internal carotid artery-related anatomy is indispensable. In the future, more series may be needed to determine the role of EEN in rNPC patients.