Imaging and Demographic Characteristics Associated with Invasion of the Medial Wall of the Cavernous Sinus in Patients with Invasive Pituitary Adenomas

Abstract Recurrence and remission rates vary widely among different histological subtypes of pituitary adenoma. Invasion of the medial wall of the cavernous sinus is a known mechanism that may account for such failed clinical outcomes as its removal has long been considered unattainable. The use of modern endoscopic techniques allows for direct intraoperative evaluation of invasion and resection of the medial wall of the cavernous sinus with low morbidity when performed by highly experienced surgeons. In this retrospective study we evaluated 105 consecutive primary pituitary adenomas operated by a single surgeon including 28 corticotroph, 27 gonadotroph, 24 somatotroph, 15 lactotroph, 5 null-cell, 5 plurihormonal, and 1 dual adenoma; 53 caused hypersecretory syndromes, specifically acromegaly (30), hyperprolactinemia (15) and Cushing’s disease (8). In each case, we performed meticulous intraoperative inspection of the medial wall with its surgical removal when invasion was suspected, regardless of functional status. Medial wall resection was performed in 46% of pituitary adenomas, and 38/48 walls confirmed pathologic evidence of invasion rendering a positive predictive value of intraoperative evaluation of medial wall invasion of 79%. Furthermore, we show for the first time that the rate of medial wall invasion among pathological subtypes is dramatically different. Somatotroph tumors invaded the medial wall much more often than other adenoma subtypes, 83% intraoperatively and 71% histologically, followed by plurihormonal tumors (40%) and gonadotrophs (33%), both with intraoperative positive predictive value of 100%. The least likely to invade were corticotroph, at a rate of 32% intraoperatively and 21% histologically, and null-cell adenomas at 0%. Removal of the medial wall caused no permanent morbidity with no carotid artery injuries and 2 patients with transient diplopia. We report that resecting the medial wall of the cavernous sinus in acromegaly offers the highest potential for biochemical remission with average postoperative day 1 GH levels at 0.96 ug/l and early surgical remission rates at 90% (100% with adjuvant therapy) based on normalization of IGF-1 levels 3 to 6 months after surgery; these results are significantly better than previously reported but longer follow-up is required for definitive conclusions. Our findings may explain the failed biochemical remission rates seen in acromegaly and illustrate the relevance of advanced surgical techniques for successful outcomes in pituitary surgery.

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Extended Endoscopic Endonasal Transsphenoidal Approach to Resect the Pituitary Adenomas Invading the Cavernous Sinus

Journal of Neurological Surgery Part B Skull Base ◽

10.1055/s-0032-1314056 ◽

2012 ◽

Vol 73 (S 02) ◽

Author(s):

Q. Wang ◽

X.-J. Lu ◽

W.-Y. Ji ◽

B. Li

Keyword(s):

Cavernous Sinus ◽

Pituitary Adenomas ◽

Transsphenoidal Approach ◽

Endoscopic Endonasal

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MICROSURGICAL ANATOMY OF THE DIAPHRAGMA SELLAE AND ITS ROLE IN DIRECTING THE PATTERN OF GROWTH OF PITUITARY ADENOMAS

Neurosurgery ◽

10.1227/01.neu.0000317321.79106.37 ◽

2008 ◽

Vol 62 (3) ◽

pp. 717-723 ◽

Cited By ~ 39

Author(s):

Alvaro Campero ◽

Carolina Martins ◽

Alexandre Yasuda ◽

Albert L. Rhoton

Keyword(s):

Pituitary Adenoma ◽

Cavernous Sinus ◽

Dura Mater ◽

Pituitary Adenomas ◽

Potential Role ◽

Pituitary Tumors ◽

Microsurgical Anatomy ◽

Suprasellar Region ◽

Lateral Distance ◽

Diaphragma Sellae

Abstract OBJECTIVE To evaluate the anatomic aspects of the diaphragma sellae and its potential role in directing the growth of a pituitary adenoma. METHODS Twenty cadaveric heads were dissected and measurements were taken at the level of the diaphragma sellae. RESULTS The diaphragma sellae is composed of two layers of dura mater. There is a remarkable variation in the morphology of the diaphragm opening. The average anteroposterior distance of the opening was 7.26 mm (range, 3.4–10.7 mm) and the average lateral-to-lateral distance was 7.33 mm (range, 2.8–14.1 mm). CONCLUSION The variability in the diameter of the opening of the diaphragma sellae could explain the growth of pituitary tumors toward the cavernous sinus or toward the suprasellar region.

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Gamma Knife robotic microradiosurgery of pituitary adenomas invading the cavernous sinus: treatment concept and results in 89 cases

Journal of Neuro-Oncology ◽

10.1007/s11060-010-0172-2 ◽

2010 ◽

Vol 98 (2) ◽

pp. 185-194 ◽

Cited By ~ 34

Author(s):

Motohiro Hayashi ◽

Mikhail Chernov ◽

Noriko Tamura ◽

Mariko Nagai ◽

Shoji Yomo ◽

...

Keyword(s):

Gamma Knife ◽

Cavernous Sinus ◽

Pituitary Adenomas ◽

Treatment Concept

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The Medial Wall of the Cavernous Sinus: Microsurgical Anatomy

Neurosurgery ◽

10.1227/01.neu.0000126953.59406.77 ◽

2004 ◽

Vol 55 (1) ◽

pp. 179-190 ◽

Cited By ~ 75

Author(s):

Alexandre Yasuda ◽

Alvaro Campero ◽

Carolina Martins ◽

Albert L. Rhoton ◽

Guilherme C. Ribas

Keyword(s):

Pituitary Gland ◽

Cavernous Sinus ◽

Thin Sheet ◽

Single Layer ◽

Lateral Wall ◽

The Body ◽

Medial Wall ◽

Microsurgical Anatomy ◽

Pituitary Fossa ◽

Adjacent Structures

Abstract OBJECTIVE: This study was conducted to clarify the boundaries, relationships, and components of the medial wall of the cavernous sinus (CS). METHODS: Forty CSs, examined under ×3 to ×40 magnification, were dissected from lateral to medial in a stepwise fashion to expose the medial wall. Four CSs were dissected starting from the midline to lateral. RESULTS: The medial wall of the CS has two parts: sellar and sphenoidal. The sellar part is a thin sheet that separates the pituitary fossa from the venous spaces in the CS. This part, although thin, provided a barrier without perforations or defects in all cadaveric specimens studied. The sphenoidal part is formed by the dura lining the carotid sulcus on the body of the sphenoid bone. In all of the cadaveric specimens, the medial wall seemed to be formed by a single layer of dura that could not be separated easily into two layers as could the lateral wall. The intracavernous carotid was determined to be in direct contact with the pituitary gland, being separated from it by only the thin sellar part of the medial wall in 52.5% of cases. In 39 of 40 CSs, the venous plexus and spaces in the CS extended into the narrow space between the intracavernous carotid and the dura lining the carotid sulcus, which forms the sphenoidal part of the medial wall. The lateral surface of the pituitary gland was divided axially into superior, middle and inferior thirds. The intracavernous carotid coursed lateral to some part of all the superior, middle, and inferior thirds in 27.5% of the CSs, along the inferior and middle thirds in 32.5%, along only the inferior third in 35%, and below the level of the gland and sellar floor in 5%. In 18 of the 40 CSs, the pituitary gland displaced the sellar part of the medial wall laterally and rested against the intracavernous carotid, and in 6 there was a tongue-like lateral protrusion of the gland that extended around a portion of the wall of the intracavernous carotid. No defects were observed in the sellar part of the medial wall, even in the presence of these protrusions. CONCLUSION: The CS has an identifiable medial wall that separates the CS from the sella and capsule of the pituitary gland. The medial wall has two segments, sellar and sphenoidal, and is formed by just one layer of dura that cannot be separated into two layers as can the lateral wall of the CS. In this study, the relationships between the medial wall and adjacent structures demonstrated a marked variability.

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