Cranium is the medical terminology for the bones of the skull. The brain is lodged inside the cranium. Craniotomy is an operative procedure that involves dealing with any pathology involving the brain through an opening in the cranium. Exenteration is a major procedure in which all the contents of a body cavity are removed. In most cases, it deals with the removal of the eye, also known as orbital exenteration.
Craniotomy is performed for orbital exenteration in which the entire eyeball, orbital soft tissues and some or all of the eyelids is removed. It is technically a very challenging procedure. It is done when cancer of the orbital contents cannot be treated by simple removal or irradiation.
Indications for Craniotomy with Exenteration
- Removal of brain tumor like meningiomas.
- Removal of mucocoeles (slow growing tumors) in the frontal sinus.
- Orbital exenteration in case of cancers of the eye and orbit.
This is done for diagnosis of the condition.
- CT scan
- Medication is given to ease anxiety before the surgery.
- Routine blood tests are done.
- The patient should not eat or drink anything after midnight the day of surgery.
- The scalp is shaved just before the operation.
- Craniotomy with exenteration is performed under general anesthesia.
- An incision is made at the nape of the neck around the bone at the back of neck (occipital bone) or a curved incision is made in front of the ear that arches above the eye. The incision is made as far as the thin membrane covering the skull.
- The scalp has a rich blood supply so any bleeding vessels should be sealed off by the surgeon.
- The skull bone is exposed by folding back the scalp tissue.
- A pattern of holes is drilled through the cranium using a high speed drill.
- A fine wire saw is used to connect the holes till a segment of bone (bone flap) can be removed. This gives access to the brain and surgery can be proceeded inside the brain.
- After the procedure is completed, the bone is replaced and secured into position with soft wire. Membranes, muscle and skin are sutured into position.
Though it is an elaborate procedure, craniotomy with exenteration is sometimes the only way to eliminate the cancer and prevent it from recurring. After the surgical site has healed, the patients can be fitted with an ocular prosthesis (plastic eye). Many patients prefer to wear an eye patch. Later, facial prosthesis can be attached to the facial skeleton.
- The patients’ pupils are tested and mental status is assessed after anesthesia.
- Breathing exercises are started shortly after surgery to clear the lungs.
- Medication is started to prevent pain, swelling and seizures. In case of orbital exenteration, eye ointment containing antibiotics and steroids is prescribed to help the healing process.
- Patients are usually hospitalized for 5 to 14 days after surgery.
- Bandages on the skull are removed and replaced regularly.
- The sutures on the skull are removed but the soft wire used to reattach the removed part of the skull is permanent and requires no further attention.
- Full recovery may take upto 2 months since patients feel fatigued till 8 weeks after surgery.
- Bleeding and blood clots.
- Retention of fluid in the brain causing swelling.
- Unintended injury to normal nerve tissues.
- Damage to normal brain tissue and loss of normal brain function like memory impairment, deafness, numbness, paralysis, double vision or loss of sense of smell.
- Growth of an abnormal orbital cyst.
- Chronic throbbing orbital pain.
- Ear problems.
- Recurrence of malignancy.
- Encyclopedia of Surgery
- An Atlas of Orbitocranial Surgery by Bryant A. Toth, Robert F. Keating
- Surgical Atlas of Orbital Diseases by Mallajosyulla