Apex Nasi: What’s Happening near the Tip of the Nose?

Abstract

The apex nasi (colloquially, the tip of the nose) is an anatomically complex region that can be divided into 2 parts: the soft tissue/cartilaginous framework of the most anterior-inferior aspect of the nose and the anterior nasal cavity. Detailed knowledge of local anatomy is helpful to characterize pathology and understand patterns of disease spread. Although many lesions of the apex nasi are readily assessed on physical examination, CT and MR imaging can provide important, often complementary, information about this region. CT well demonstrates osseous anatomy, while MR imaging offers increased specificity for certain conditions, given its superior soft-tissue contrast. Regarding specific pathologies of the region, because cutaneous cancers are common and often involve the apex nasi, they will be discussed in detail, along with potential imaging pitfalls such as perineural tumor spread or coexistence with rhinophyma. Certain rare non-neoplastic or developmental lesions, notably nasolabial cysts and pyriform aperture stenosis, are unique to this region. Vascular lesions such as angiosarcoma and venous malformation may involve the apex nasi, as may nasal septal hematoma and abscess, the latter necessitating immediate treatment. Given the high prevalence of rhinoplasty, the imaging appearance of cosmetic nasal implants and selected rare procedural complications is shown.Learning Objective: To describe the anatomic landmarks of the external nose and anterior nasal cavity and to illustrate common and uncommon pathologies in these locations.