**9.2 Transcranial approaches**

The majority of patients can be treated using transsphenoidal route. However, a few of pituitary adenomas may require transcranial approaches for resecting adenoma extensions that cannot be reached by transsphenoidal route.

Common indications for transcranial surgery in pituitary adenomas include:

1.Lateral and significant suprasellar adenoma extensions to critical neurovascular structures.

*Pituitary Adenomas: Classification, Clinical Evaluation and Management DOI: http://dx.doi.org/10.5772/intechopen.103778*

#### **Figure 11.**

*Preoperative MRI (A and B) and postoperative CT scan (C and D) for a senior male patient who was complaining form headache and progressive visual dysfunction. The patient was operated in outside hospital through transsphenoidal approach. Incomplete excision was done. However, the patient developed decrease in the level of consciousness and oculomotor nerve dysfunction after surgery. Brain CT scan showed excessive hemorrhage in the unresected intracranial part of the adenoma.*


Other uncommon indications include patients with obstructive sleep apnea who could not be weaned off CPAP or concomitant aneurysm that is in proximity to the sellar area.

Recurrent adenomas are no longer an indication for transcranial surgery [76, 77]. Also, giant adenomas (>4 cm) used to be an indication for transcranial surgery, but due to recent advancements in endoscopic approaches, large size adenomas can be effectively treated through transsphenoidal route [78].

In dealing with giant pituitary adenomas that encasing nearby neurovascular structures, both transsphenoidal and transcranial may be needed, especially when the goal of surgery is gross total excision in functional-adenoma cases.

But what approach should be the first choice, the transsphenoidal or the transcranial surgery?

The answer of this question relies on the understanding of the blood supply of pituitary adenomas. These tumors share the same blood supply of normal pituitary gland which comes from inferior and superior hypophyseal arteries. In general, pituitary adenomas have low vascular density which may explain their slow growth [77]. Attacking the adenoma through transsphenoidal route will result in acute devascularization of the remaining unresected adenoma which result in intratumoral necrosis and subsequently hemorrhage (**Figure 11**). Therefore, it is preferred to go transcranially first then to operate transsphenoidal [79, 80].

Transcranial approaches that commonly utilized to deal with pituitary adenomas include pterional, orbitozygomatic, bifrontal, and supraorbital approaches. The choice of the approach depends on tumor extension and the neurovascular structures that are needed to be addressed intraoperatively.
