Mastoidectomy Surgery In India
A mastoidectomy is an operation to remove an infection or skin growth behind your eardrum together with the surrounding (mastoid) bone.
Mastoid surgery is performed when infections in the middle ear spread to the mastoid cavity. Commonly a pocket of skin develops on the ear drum and may invade the middle ear and subsequently the mastoid. This may cause recurrent ear discharge.
A simple mastoidectomy consists of opening the mastoid cortex and identifying the aditus ad antrum.
A complete or canal wall up mastoidectomy necessitates removal of all of the mastoid air cells along the tegmen, sigmoid sinus, presigmoid dural plate, and posterior wall of the external auditory canal. The posterior wall of the external auditory canal is preserved.
A canal wall down mastoidectomy includes a complete mastoidectomy in addition to removal of the posterior and superior osseous external auditory canal. The tympanic membrane is reconstructed to separate the mucosal lined middle ear space from the mastoid cavity and ear canal.
A modified radical mastoidectomy is identical to a canal wall down mastoidectomy except the middle ear space and native tympanic membrane are not manipulated. This procedure is useful when there is no extension of cholesteatoma in the middle ear space or medial to the malleus head or incus body. This procedure is often indicated in patients with a cholesteatoma in their only or better hearing ear.
A radical mastoidectomy is a canal wall down mastoidectomy in which the tympanic membrane and ossicles are not reconstructed, thus exteriorizing the middle ear and the mastoid. The eustachian tube is often obliterated with soft tissue to reduce the risk of a chronic otorrhea. A skin graft can be placed in the middle ear to reduce the risk of mucosalization and otorrhea.
Successful and safe mastoid surgery requires routine identification of key anatomic structures including but not limited to the tegmen (middle fossa floor), sigmoid sinus, external auditory canal, lateral semicircular canal, and facial nerve.
A high-speed electric or pneumatic drill with various tools and attachments are used in conjunction with copious suction irrigation when performing mastoid surgery. Adequate irrigation serves to wash away bone dust generated by the drill to improve visualization. Irrigation also decreases the risk of injury from overheating of various structures traversing the temporal bone.
The operating microscope with various magnification setting provides the surgeon with improved visualization of anatomic landmarks and critical structures traversing the temporal bone.
Indications Of Mastoidectomy
Chronic otitis media (COM), with or without cholesteatoma, is one of the more common indications for performing a mastoidectomy. Patients with chronic otitis media often present with otorrhea and progressive hearing loss. Mastoidectomy permits access to remove cholesteatoma matrix or diseased air cells. In addition, mastoidectomy often provides access to the temporal bone which are more challenging to visualize through the external auditory canal (ie, supratubal recess, epitympanum, facial recess, perilabyrinthine air cells, retrofacial air cells).
Mastoidectomy is one of the key steps in placing a cochlear implants to rehabilitate acquire or congenital sensorineural hearing loss. A mastoidectomy allows the surgeon access to the middle ear through the facial recess. The implant electrode array is placed through the facial recess into a cochleostomy, which is drilled inferior and slightly anterior to the round window.
A mastoidectomy is often an initial step in removal of lateral skull base neoplasms, including vestibular schwannomas, meningiomas, temporal bone paragangliomas (glomus tumors), and epidermoids.