The Transsphenoidal Removal of Nonfunctioning Pituitary Adenomas with Suprasellar Extensions

Abstract

The surgical treatment of large pituitary adenomas with suprasellar extensions has been controversial. To elucidate the indications for transsphenoidal surgery of large adenomas and to evaluate the techniques for removing the suprasellar portions of the tumors, surgical procedures on 100 consecutive patients with suprasellar extensions of nonfunctioning pituitary adenomas were retrospectively investigated. Patients were followed up for 1 to 12 years (mean, 4.5 yr). One hundred twenty-five transsphenoidal operations were performed on 100 patients. The removal of each suprasellar tumor was facilitated by the placement of a lumbar subarachnoid catheter and the injection of lactated Ringer's solution or saline. This method was used in 77 operations and was effective on 60 of 72 adenomas with < 30-mm suprasellar extensions (Hardy's Grades A, B, and C) but not on those that were fibrous or dumbbell-shaped. The descent of the remaining suprasellar tumor was facilitated by keeping the sella and sellar floor open with an intrasellar drain, and the subsequent removal was achieved with staged transsphenoidal operations. Of nine fibrous or dumbbell-shaped adenomas with 10- to 30-mm suprasellar extensions, gross total removal in eight was achieved by the open sella technique and two-stage transsphenoidal operation, whereas one required transcranial surgery. Adenomas with > 30-mm suprasellar or lateral extensions (Grade D) could not be removed sufficiently by transsphenoidal operations, except one adenoma for which a subtotal removal was achieved in the third staged operation. The disease-free rate 10 years after operation was 74% for all patients: 91% for Grade A, 74% for Grade B, and 61% for Grade C.(ABSTRACT TRUNCATED AT 250 WORDS)

Expanding the boundaries of the transsphenoidal approach: A microanatomic study

“…However, extension of the transsphenoidal approach beyond the limits of the sella turcica into the cavernous sinus or the supradiaphragmatic intradural space remains a challenge. Modifications of the transsphenoidal approach to expose these areas have been described (Fraioli et al, 1995;Lalwani et al, 1992;Mason et al, 1997;Petruson et al, 1997;Saito et al, 1995). Because a thorough understanding of the extended microsurgical anatomy of the sphenoid sinus, sella turcica, and surrounding structures is critical to maintain the safety and efficacy of pituitary surgery, we discuss the microsurgical anatomy of the structures in the sellar region that are generally beyond the limits of a standard transsphenoidal approach (i.e., tuberculum sellae, planum sphenoidale, supradiaphragmatic intradural space, and medial cavernous sinus).…”

“…Saito et al (1995) reported 100 (16%) cases of suprasellar extension in their series of 610 pituitary tumors. A standard transsphenoidal approach is commonly used to treat these lesions, supported by maneuvers that facilitate the descent of the tumor into the sella (e.g., Valsalva maneuver, jugular vein compression, and lumbar infusion).…”

“…A standard transsphenoidal approach is commonly used to treat these lesions, supported by maneuvers that facilitate the descent of the tumor into the sella (e.g., Valsalva maneuver, jugular vein compression, and lumbar infusion). Other treatment options for a significant suprasellar extension of a tumor include staged transsphenoidal removal (Mohr et al, 1990;Saito et al, 1995), with or without the use of the open sella method (Saito et al, 1995), a combined transsphenoidal and intracranial approach (Burian et al, 1970;Laws et al, 1977;Loyo et al, 1984), and a transcranial approach only. Recently, Mason et al (1997) described a transsphenoidal approach extended to the supradiaphragmatic intradural space to remove lesions at the level of the pituitary stalk.…”

“…Modifications of the transsphenoidal approach have been proposed in an attempt to enhance the surgical resection of these tumors (Fraioli et al, 1995;Lalwani et al, 1992;Mason et al, 1997;Petruson et al, 1997;Saito et al, 1995). Mason et al (1997) recently described a surgical technique that extends the transsphenoidal approach to the planum sphenoidale, entering the suprasellar cistern to remove lesions at the level of the pituitary stalk.…”

Transsphenoidal surgery

“…In cases of macroadenoma it is important to delineate the relationships of the tumour to surrounding neurovascular structures including the optic nerves and chiasm, the cavernous sinus, sphenoid and clival bones, and the extent of suprasellar extension. If the tumour is soft, then large suprasellar extensions can be removed transsphenoidally by iatrogenic intra-operative elevation of the intracranial pressure [5]. Contraindications to surgery are summarised in Table 1.…”