Transsphenoidal resection of hypophyseal tumorMedical editor Jon Berg-Johnsen MD
Oslo University Hospital
The preoperative assessment involves an endocrinological investigation, a vision test and an MR image of the hypophysis. In the event of hormone failure the patient should preferably be placed on hormone replacement therapy before the procedure.
The majority of hypophyseal tumors can be operated on using transsphenoidal access through the nose. In extreme circumstances, the largest tumors must be operated by craniotomy with subfrontal access in order to preserve vision.
The patient will be informed that further growth of the tumor and the operation itself can result in hypophyseal failure. If hypophysis function is normal before the operation, it is relatively rare for the patient to suffer hypophyseal failure as a result of the procedure.
The operation takes place under general anesthesia. An endoscope or operation microscope is used to provide good illumination and magnification, and X-ray examination is used to simplify orientation with regard to anatomic landmarks. The operative access is long and narrow, which hampers instrumentation. The consistency of the tumor and the extent of its growth outside the sella turcica (hypophyseal cavity) are of significance regarding how much of the tumor that can be removed. Most hypophyseal adenomas are soft. The tumor capsule is left to prevent spinal fluid leak.
The method of operation is gentle for the brain and achieves good results with a low risk of complications in the majority of cases.
Tumors (with the exception of prolactinomas) that lift and compress the sensory organs
Hormone-producing tumors (growth hormone - acromegaloidism/gigantism, ACTH - Cushing, thyroxin)
Prolactinomas that do not shrink with drug therapy
Relieve the optic nerves and optic nerve junction
Preserve hypophysis function
The preoperative assessment involves an endocrinological investigation, and any hypophyseal failure must be diagnosed and corrected before the procedure.
The patient lies in the supine position.
The procedure is carried out under general anesthesia.
Tampons are inserted in the throat.
Local anesthetic is injected into the nasal septum.
Antibiotics are given peroperatively.
The surgeon begins by entering the right nostril and identifying the anatomic opening to sphenoidal sinus. The opening is expanded and the endoscope is inserted.
The hypophyseal cavity is opened.
The dura is coagulated and opened by a cross-shaped incision, and the tumor can be accessed.
A frozen and formalin fixed biopsy are taken for histology.
The tumor is carefully resected with curettes in all directions.
The hypophysis is often seen as yellowish, more compact tissue.
The residual tumor is removed with biopsy forceps until properly emptied.
When finishing, good hemostasis must be achieved.
An artificial dura (Neuropatch) is cut to size and applied to the inside of the dura.
Tissue glue and a new artificial dura are applied under the bone edges.
The sphenoidal sinus is filled with Spongostan.
- S-cortisol is measured the following morning after surgery. When required, supplementary cortisone is given.
- Spinal fluid leakage from the nostrils
- Fluid intake and urination
After the operation, the patient will stay in the hospital for two days and then be transferred to their local hospital or according to the clinical condition.
Follow-up is carried out at the endocrinology department after three months with hormone tests, vision examinations, and MRI. The endocrinology department will follow up the patient with further hormone testing/substitution and MRI examinations.
Regrowth of the tumor occurs in 20% of patients and requires new surgery. Patients who are operated multiple times will be considered for radiation therapy.
- Cerebrospinal fluid leakage from the nose/throat
- Diabetes insipidus
- Vision nerve injury
- Infection (meningitis)