The components of the<unk>  involved in<unk>  are the outer skin, the perichondrium, and the cartilage. The outer<unk>  skin is tightly adherent to the perichondrium because there is almost no subcutaneous fat on the anterior of the<unk> . This leaves the perichondrium relatively exposed to damage from direct trauma and shear forces, created by a force pushing across the<unk>  like a punch, and increasing the risk of hematoma formation. In an auricular hematoma, blood accumulates between the perichondrium and cartilage. The hematoma mechanically obstructs blood flow from the perichondrium to the avascular cartilage. This lack of perfusion puts the cartilage at risk for becoming necrotic and/or infected. If left untreated, disorganized fibrosis and cartilage formation will occur around the aforementioned cartilaginous components. Consequently, the concave pinna fills with disorganized connective tissue. The cartilage then deforms and kinks, resulting in the distinctive appearance somewhat resembling a<unk> . Rapid evacuation of the hematoma restores close contact between the cartilage and perichondrium, thereby reducing the likelihood of deformity by minimizing the ischemia that would otherwise result from a remaining hematoma. Auricular hematoma most often occurs in the potential space between the helix and the antihelix (scapha) and extends anteriorly into the fossa triangularis. Less frequently, the hematoma may form in the concha or the area in and around the external auditory meatus. Importantly, an auricular hematoma can also occur on the posterior<unk>  surface, or even both surfaces. Risk of necrotic tissue is greatest when both posterior and anterior surfaces are involved, although posterior surface involvement is less likely given its increased quantity of impact-dampening subcutaneous tissue.
Cauliflower ear
Hemotympanum
Philinus of Cos
Fibrous papule of the nose
Syrinx 
Lacrimal groove
Ayer's Sarsaparilla
Orbital septum