Cysts dermoid

Dermoid cyst Epidermoid cyst features plus adnexa of skin cyst contains sebum, squames, and hair Keratin (-r) Midline cerebellum fourth ventricle skull spinal dura cauda equina... 

Dermoid cysts are frequently midline cysts, possibly arising from embryonic inclusions of skin at the time of closure of the neural groove (see Table 20.13). They occur between the cerebellar hemispheres, in the fourth ventricle, in the lumbosacral region of the cord, and in the skull. These cysts may involve CNS, meninges, or both. Ruptured dermoid cysts can cause sterile meningitis and inflammation resembling an abscess. Identification of squamous epithelial cells with CK or cholesterol clefts within the inflammation are clues to its true cause. 

Dermoid cysts or mature cystic teratomas are composed of mature tissue from at least two of the three... 

In the vast majority (88%), dermoid cysts are uni-lociflar cystic lesions filled with sebaceous material. A protuberance, the Rokitansky nodule, or dermoid plug, projects into the cavity and is the hallmark of dermoids (Fig. 9.17). It contains a variety of tissues, often including fat and calcifications, which represent teeth or abortive bone. Fat is detected in over 90%,... 

A minority of dermoid cysts will demonstrate no fat or only small foci of fat within the wall or the Rokitansky nodule (Fig. 9.28) [73]. Yamashita et al. reported that 15% of mature teratomas did not show fat within the cystic cavity. Approximately half of these cases displayed small amounts of fat within the wall of the dermoid or the dermoid plug. In 8% of henign teratomas, no fat could be detected [73]. 

Sonographic assessment of dermoid cysts is often limited by its variety of appearance. 

Caspi B,AppelmanZ,RabinersonDet al (1997) The growth pattern of ovarian dermoid cysts a prospective study in premenopausal and postmenopausal women. Fertil Steril... 

Bazot M, Cortez A, Sananes S, Boudghene F et al (1999) Imaging of dermoid cysts with foci of immature tissue. J Comput Assist Tomogr 23 703-706... 

Ekici E, Soysal M, Kara S, Dogan M, Gokmen O (1996) The efficiency of ultrasonography in the diagnosis of dermoid cysts. Zentralbl Gynakol 118 136-141... 

The finding of a cystic ovarian tiunor, especially a dermoid cyst in young women who present with acute pain and vomiting is highly suspicious of adnexal torsion. 

These lesions result from the proliferation of epidermal cells within a circumscribed space of the dermis. They are composed of keratin producing epithelium and can be distinguished from dermoid cysts, which contain skin and skin appendages, and from sebaceous cysts. 

The appearance of penile dermoid cysts at ultrasound and magnetic resonance imaging has not been described, but it is conceivable that it should be similar to that of dermoid cysts in the scrotum (Dogra et al. 2001). 

These lesions are extremely rare in the penis with only few cases reported in the literature (Aidarov and Zolotarev 1962 Tomasini et al. 1997). In contrast to epidermoid cysts, dermoid cysts are lined by an epidermis that possesses various fully mature epi-... 

Aidarov AA, Zolotarev MA (1962) [Dermoid cyst of the penis.]. Urol Mosc 27 71... 

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