Auricular pseudocyst, also known as non-suppurative perichondritis of the auricle, serous perichondritis of the auricle, and intracartilaginous effusion of the auricle, is a cyst formed by non-suppurative serous effusion in the interlayer of the auricular cartilage, mostly in the upper half of the outer front of the auricle, with serous exudate, forming a cystic bulge, often unilateral. Males are more affected than females, mainly in adults age 20 - 50.
Etiology
Etiology has not yet been clearly determined, and may be related to trauma or certain mechanical stimulation, such as collision and compression, causing local circulation disturbance and accumulation of reactive exudate between tissues. It is also believed that it is congenital dysplasia, that is, the abnormal fusion of the six ear hillocks of the first and second branchial arches of the embryo leaves a potential tissue lacuna, leaving a tissue basis for the occurrence of auricular pseudocyst.
Pathology
The cyst is not between the perichondrium and the cartilage but between the cartilage layers. Therefore, pathologically, it is intercartilaginous effusion. The inner side of the cartilage layer is covered with serous cellulose, and there is no epithelial cell structure on its surface, so it is not a true cyst.
Clinical manifestations
The cystic bulge is mostly in the navicular fossa and triangular fossa, occasionally in the cavity of the concha, but not the dorsal auricle. Patients often accidentally find a localized bulge on the front and upper part of the auricle, which gradually increases. With small pseudocyst, patients may have no symptoms, while with large one, patients may have fullness sensation, fluctuation, burning sensation, and pruritus, often with no pain or only mild pain. The cyst has clear boundaries and the color of the affected skin is normal. The light transmittance is good during transillumination, which can be used to distinguish from hematoma. Light yellow clear fluid can be extracted, and bacterial growth cannot be found in culture.
Figure 1 Auricular pseudocyst
Treatment
Physiotherapy such as ultraviolet irradiation and ultrashort wave can be used in the early stage to stop exudation and promote resorption. There are also reports of treatments such as wax therapy, magnetotherapy, cryotherapy, and radiofrequency.
The cyst fluid can be extracted under sterile conditions, and the local area is fixed and compressed with plaster or compressed with gauze strips, and is dressed with gauze or bandage. Two round magnets (about 1.5 cm in diameter) can also be placed in front and behind the auricle of the cyst site, and the local area is compressed with the attraction of the magnets.
15% hypertonic saline or 50% glucose solution is injected into the cyst cavity after fluid extraction, the site is non-pressure dressed, and the injected fluid is extracted in 24 hours; repeated injection and extraction are performed, until the extracted fluid turns red, which can promote adhesion and organization of the cyst wall. However, the cure rate is sometimes not ideal, and the local area often thickens and deforms after healing.
Surgery can provide ideal results in most patients. The cartilage on the outer wall of the cyst cavity is incised, and the accumulated fluid is completely drained. If there is granulation in the cyst, it should be removed. A drain can be placed in the surgical cavity, the incision is sutured when wound edges are aligned and everted, and pressure dressing lasts for about 2 days.