Transsphenoidal adenomectomy in Cushing's disease via a lateral rhinotomy approach

Long-Term Outcomes and Complications from Endoscopic Versus Microscopic Transsphenoidal Surgery for Cushing's Disease: A 15-Year Single-Center Study

BACKGROUND

Endoscopic endonasal surgery is the main transsphenoidal approach for pituitary surgery in many centers; however, few studies compare the endoscopic and microscopic surgical approaches with regard to long-term follow-up. This single-center study aimed to compare the 2 techniques over 15 years.

METHODS

Medical records and magnetic resonance images from 40 patients with primary transsphenoidal surgery for Cushing's disease at Sahlgrenska University Hospital between 2003 and 2018 were reviewed. 14 patients who underwent microscopic surgery and 26 patients who underwent endoscopic surgery were included in this study.

RESULTS

In the microscopic group, 12 of 14 patients achieved endocrine remission, compared to 19 of 26 patients in the endoscopic group (n. s.). Three patients in each group developed a late recurrence. Complications were seen in 5 patients in the microscopic group and in 8 patients in the endoscopic group (n. s.). No serious complications, such as carotid artery damage, cerebrovascular fluid leakage, epistaxis, or meningitis, occurred in any group. The postoperative hospital stay was shorter in the endoscopic than in the microscopic group.

CONCLUSIONS

Endoscopic endonasal surgery for Cushing's disease showed no difference in remission, recurrence, and complication rates compared to the microscopic approach. The endoscopic group had a shorter postoperative hospital stay than the microscopic group, which in part may be due to the minimal invasiveness of the endoscopic approach.

Endoscopic vs. microscopic transsphenoidal surgery for Cushing's disease: a systematic review and meta-analysis

PURPOSE

Systematic review and meta-analysis comparing endoscopic and microscopic transsphenoidal surgery for Cushing's disease regarding surgical outcomes (remission, recurrence, and mortality) and complication rates. To stratify the results by tumor size.

METHODS

Nine electronic databases were searched in February 2017 to identify potentially relevant articles. Cohort studies assessing surgical outcomes or complication rates after endoscopic or microscopic transsphenoidal surgery for Cushing's disease were eligible. Pooled proportions were reported including 95% confidence intervals.

RESULTS

We included 97 articles with 6695 patients in total (5711 microscopically and 984 endoscopically operated). Overall, remission was achieved in 5177 patients (80%), with no clear difference between both techniques. Recurrence was around 10% and short term mortality < 0.5% for both techniques. Cerebrospinal fluid leak occurred more often in endoscopic surgery (12.9 vs. 4.0%), whereas transient diabetes insipidus occurred less often (11.3 vs. 21.7%). For microadenomas, results were comparable between both techniques. For macroadenomas, the percentage of patients in remission was higher after endoscopic surgery (76.3 vs. 59.9%), and the percentage recurrence lower after endoscopic surgery (1.5 vs. 17.0%).

CONCLUSIONS

Endoscopic surgery for patients with Cushing's disease reaches comparable results for microadenomas, and probably better results for macroadenomas than microscopic surgery. This is present despite the presumed learning curve of the newer endoscopic technique, although confounding cannot be excluded. Based on this study, endoscopic surgery may thus be considered the current standard of care. Microscopic surgery can be used based on neurosurgeon's preference. Endocrinologists and neurosurgeons in pituitary centers performing the microscopic technique should at least consider referring Cushing's disease patients with a macroadenoma.

The experience with transsphenoidal surgery and its importance to outcomes

PURPOSE

Surgical experience is considered paramount for excellent outcome of transsphenoidal surgery (TSS). However, objective data demonstrating the surgical success in relation to the experience of pituitary surgery units or individual experience of pituitary surgeons is sparse.

METHODS

Based on literature data, we have investigated the influence of experience with TSS for pituitary adenomas on endocrinological remission rates and on operative complications. The surgical experience was assessed by calculating the number of transsphenoidal operations per year.

RESULTS

For TSS of microprolactinomas, mean remission rates were 77% in centers with < 2 operations per year for microprolactinomas, 82% with 2-4 operations, 84% with 4-6 operations, and 91% with > 6 operations. A yearly experience with more than 10 initial operations for Cushing's disease (CD) warrants a remission rate exceeding 70%. Remission rates in CD exceeding 86% have only been reported for single surgeon series. Extraordinarily high complication rates were found in some series with < 25 yearly total operations for pituitary adenomas. Major vascular complications were less than 2% and revision rates for rhinorrhea usually < 2.5% in centers performing > 25 transsphenoidal operations per year.

CONCLUSIONS

We conclude that a center with experience of > 25 transsphenoidal operations for pituitary adenomas per year provides a high likelihood of safe TSS. Surgery for CD requires a particularly high level of practice to guarantee excellent remission rates. The endocrinologist has the unique opportunity to audit the surgical success by hormone measurement and to refer patients to neurosurgeons with proven excellence.

Extended transsphenoidal approach with submucosal posterior ethmoidectomy for parasellar tumors. Technical note

The authors have developed an extended transsphenoidal approach with submucosal posterior ethmoidectomy for resection of tumors located in the cavernous sinus or the suprasellar region that are difficult to remove via the conventional transsphenoidal approach. Surgery was performed using this approach in 14 patients with large pituitary adenomas, three patients with craniopharyngiomas, and one patient with a meningioma of the tuberculum sellae. The submucosal dissection of the nasal septum used in the conventional transsphenoidal approach was extended to the superior lateral wall of the nasal cavity to expose the bony surface of the superior turbinate lying under the nasal mucosa. Submucosal posterior ethmoidectomy widened the area visualized through the conventional transsphenoidal approach both superiorly and laterally. This provided a safer and less invasive access to lesions in the cavernous sinus or the suprasellar region through the sphenoid sinus. Using this approach the authors encountered no postoperative complications, such as olfactory disturbance, cranial nerve palsy, or arterial injury. In this article the authors present the surgical methods used in this approach.

Expanding the boundaries of the transsphenoidal approach: a microanatomic study

The anatomic features of a transsphenoidal approach are reviewed, focusing on the microsurgical anatomy of parasellar structures. Pertinent microsurgical anatomy is described in sufficient detail for the neurosurgeon to successfully extend a standard transsphenoidal approach for treatment of lesions involving the region of the tuberculum sellae, planum sphenoidale, supradiaphragmatic intradural space, and medial cavernous sinus. The parasellar region of 50 formalin-fixed cadaveric heads was examined by using magnification 3x to 40x. The arterial and venous systems of five cadaveric specimens were injected under pressure with colored silicone rubber. The sellar region of three specimens was examined histologically. Important anatomic landmarks identified in the roof of the sphenoid sinus include a carotid and trigeminal prominence, as well as a tubercular, clival, and opticocarotid recess. The diaphragma sella is actually comprised of two layers of dura, with a venous system (circular sinus) interposed between the layers. The dura mater of the pituitary gland separates the gland from the medial compartment of the cavernous sinus. The microanatomic detail necessary to extend the transsphenoidal approach to the supradiaphragmatic intradural space and medial compartment of the cavernous sinus is described. These data are presented to facilitate the clinical application of these extended approaches.