The management of giant and large pituitary adenomas with wide intracranial extension or infrasellar involvement of nasal and paranasal cavities is a big challenge for neurosurgeons and the best surgical approach indications are still controversial. Endoscopic extended endonasal approaches have been proposed as a new surgical technique for the treatment of such selected pituitary adenomas. Surgical series coming from many centers all around the world are flourishing and results in terms of outcomes and complications seem encouraging. This technique could be considered a valid alternative to the transcranial route for the management of giant and large pituitary adenomas.
Key points
- •
The endoscopic endonasal approach is a valuable treatment of large and giant adenomas.
- •
The extended approach gives the opportunity to access pituitary lesions via a double corridor (ie, intracapsular and extracapsular).
- •
The reconstruction of the osteodural defect is mandatory for extended approach.
Introduction
Among all the intracranial tumors, pituitary adenomas represent the third most common lesion, with a prevalence of 16.9% in autopsy studies. The management of these lesions can become particularly challenging especially in those classified as large or giant and with wide intracranial extension or prevalent inferior involvement down into the nasal and paranasal cavities. Adenoma can be defined as “giant” if the maximum diameter is bigger than 4 cm, but there is no consensus about the definition of large pituitary adenomas. The conventional transcranial approach has been traditionally the first choice for the removal of large intracranial adenomas, because of limited visualization beyond the sella provided by microscopic transsphenoidal approaches. The improved visualization gained with the introduction of the endoscope, adopted over the past two decades for the treatment of pituitary adenomas and other sellar lesions, has opened the possibility of removing lesions that grow considerably beyond the sella, thus greatly increasing the number of tumors being approached via the transsphenoidal route. Although in many neurosurgical centers worldwide endoscopic approaches are now routinely used in clinical practice, there are still some controversies concerning the safety and effectiveness of approaching large and giant pituitary adenomas via an endoscopic endonasal approach.
Indications
Pituitary adenomas are a heterogeneous group of lesions. According to the biologic, endocrinologic, and pathologic viewpoint, the main goal of surgery for the removal of giant or large lesions should be, regardless of the hormonal status, relief of mass effect, preservation or restoration of normal neurologic function, and decompression of the pituitary gland to improve or preserve residual hormonal function. The extended endonasal transsphenoidal approach has become well established in a conspicuous number of centers, and it is adopted with expanding indications for a variety of midline skull-base lesions.
The transtuberculum/transplanum approach has been introduced during the last decade to address selected midline suprasellar lesions, such as craniopharyngiomas, Rathke cleft cysts, or tuberculum sellae meningiomas. Currently, several authors report on pituitary adenomas series treated with such an extended approach, thus expanding the indications for endonasal resection of these lesions, especially for those tumors with a prevalent intracranial extension. Nowadays, it is possible to use extended endonasal approaches for dumbbell-shaped adenomas, pure suprasellar adenomas or adenomas whose suprasellar component fails to descend within the sella after sellar debulking, adenomas extended over the tuberculum or planum sphenoidale, giant symmetric or asymmetric adenomas, or adenomas invading the cavernous sinuses ( Figs. 1–3 ). However, we should conceive an “extended approach” not only targeted to suprasellar or parasellar regions: an infrasellar variation of the technique with a wider removal of nasal structures allows the surgeon to obtain an easier removal of those lesions with a prevalent extracranial extension, such as adenomas invading the whole sphenoid sinus cavity, with erosion of the clivus or extension to the pterygoid fossa or the nasal cavities ( Table 1 ).
Related posts:
Endoscopic Endonasal Skull Base Surgery
Endoscopic Endonasal Repair of Spontaneous and Traumatic Cerebrospinal Fluid Rhinorrhea
Endoscopic Endonasal Approach for Removal of Tuberculum Sellae Meningiomas
Endoscopic Endonasal Approach to Ventral Posterior Fossa Meningiomas
Endoscopic Endonasal Odontoidectomy
Chordomas
Stay updated, free articles. Join our Telegram channel
Full access? Get Clinical Tree
