Several synonyms exist for epidermoid cysts, including epidermal cyst , infundibular cyst , keratin cyst and the technically incorrect, epidermal inclusion cyst .  : 778  "Epidermal inclusion cyst" more specifically refers to implantation of epidermal elements into the dermis . The term infundibular cyst refers to the site of origin of the cyst: the infundibular portion of the hair follicle . In fact, the majority of epidermal inclusion cysts originate from the infundibular portion of the hair follicle thus explaining the interchangeable,  yet inaccurate, use of these two terms. Another similar and easily confused cyst is Sebaceous cyst .
Surgical excision is required to treat a trichilemmal cyst. The method of treatment varies depending on the physician 's training. Most physicians perform the procedure under local anesthetic . Others prefer a more conservative approach. This involves the use of a small punch biopsy about 1/4 the diameter of the cyst. The punch biopsy is used to enter the cyst cavity. The content of the cyst is emptied, leaving an empty sac. As the pilar cyst wall is the thickest and most durable of the many varieties of cysts, it can be grabbed with forceps and pulled out of the small incision. This method is best performed on cysts larger than a pea which have formed a thick enough wall to be easily identified after the sac is emptied. Small cysts have walls that are thin, and easily fragmented on traction. This increases the likelihood of cyst recurrence. This method often results in only a small scar, and very little if any bleeding.