Sequestration Dermoid Complications and Treatment

Sequestration Dermoid

 

sequestration dermoid occurs at the line of embryonic fusion, due to the inclusion of epithelium beneath the surface which later gets sequestered forming a cystic swelling in the deeper plane.

• sequestration dermoid is a congenital type.
• Common sites are:

• Forehead, neck, postauricular dermoid.
• External angular dermoid.
• The root of the nose.
• Sublingual dermoid.
• Anywhere in midline or in the line of fusion.
• Dermoids occurring in the skull may extend into the cranial cavity.
• When it occurs as an external angular dermoid, it extends into the orbital cavity, or it can extend into any cavity about its anatomical location (e.g. thorax, abdomen).

Sequestration Dermoid Types Of Angular Dermoid

• External angular dermoid: lt is a sequestrationdermoid situated over the external angular process of the frontal bone.
  The outer extremity of the eyebrow extend over some part of the swelling.
  This feature diffrentiate it from swelling arising from lacrimal gland.
  It can extend to the orbital cavity also.
• Internal angular dermoid: lt is a sequestration dermoid cyst in the central position near the root of the nose.
  sequestration dermoid occurs in frontonasal suture line. It mimics swelling from the lacrimal sac or mucocele of the frontal sinus.
  Mucocele of frontal sinus is due to blockage of frontonasal duct.

Sequestration Dermoid Clinical Features

• Painless swelling in the line of embryonic fusion.
• Seen in second or third decades of life.
• It is smooth, soft, non-tender and fluctuant and non transilluminating
• There is presence of resorption and indentation of bone beneath.
• Impulse on coughing may be present only if there is an intracranial extension.

Sequestration Dermoid Complications

• Infection
• Hemorrhage
• Surface ulceration
• Calcification.

Sequestration Dermoid Investigations

• X-ray skull or part
• CT-scan head or part.

Sequestration Dermoid Treatment

Excision is done under general anesthesia.
Often formal neurosurgical approach is required by raising cranial osteocutaneous flips.