Clinical outcomes of endoscopic versus microscopic trans-sphenoidal surgery for large pituitary adenoma

Endoscopic and exoscopic surgery for brain tumors

Nerves and blood vessels must be protected during brain tumor surgery, which has traditionally relied on microscopes. In the 2000s, endoscopes and related equipment were developed for neurosurgery. In this review, we aim to outline the role of endoscopes in brain tumor surgery and discuss the emerging use of exoscopes. The primary use of endoscopes in brain tumor surgery is in endoscopic endonasal surgery for pituitary tumors. By using the space within the sphenoid sinus, surgeons can insert an endoscope and instruments such as forceps or scissors through the nose to access and remove the tumor. Compared to microscopes, endoscopes can get closer to tumors, nerves, and blood vessels. They enable wide-angle observation of the skull base, making them valuable for skull base tumors as well as pituitary tumors. Endoscopes are also used in cases where a brain tumor is associated with hydrocephalus, allowing surgeons to correct obstructive hydrocephalus and perform tumor biopsies simultaneously. Exoscopy, a newer technique introduced in recent years, involves surgeons wearing special glasses and removing the tumor while viewing a three-dimensional monitor. This approach reduces surgeon fatigue and allows for more natural positioning during lengthy brain tumor surgeries. Future brain tumor surgeries will likely involve robotic surgery, which is already used for other organs. This is expected to make brain tumor removal safer and more accurate.

Comparison of Surgical Modalities for Giant Pituitary Adenoma: A Systematic Review and Meta-Analysis of 1413 Patients

BACKGROUND AND OBJECTIVES

Giant pituitary adenomas (GPAs) are a challenging clinical entity, composing 5% to 15% of all pituitary adenomas. While the endoscopic endonasal transsphenoidal (EET) approach has surpassed the microsurgical transsphenoidal (MT) and transcranial (TC) approaches as the first-line surgical modality in most institutions, a systematic review comparing the 3 approaches has not been undertaken since 2012. Given growing adoption of EET and development of novel operative techniques over the past decade, an updated comparison of GPA surgical modalities is warranted.

METHODS

We identified all studies related to the surgical management of GPAs in PubMed, Embase, and Web of Science from inception to December 31, 2021. End points assessed included gross total resection (GTR) rates, postoperative visual improvement, mortality, and perioperative complications.

RESULTS

After screening of 1701 studies, we identified 45 studies on the surgical management of GPAs for meta-analysis. Thirty-one used the EET approach (n = 1413), 11 studies used the MT approach (n = 601), and 10 used the TC approach (n = 416). The cumulative number of patients treated by EET did not exceed that of patients treated by the TC or MT approaches until 2014 and 2015, respectively. Despite patients undergoing EET having the highest average tumor diameter, pooled rates for GTR were significantly higher for EET (42%) than MT (33%, P < .001) and TC (8%, P < .001) and EET similarly exhibited superior rates of visual improvement (85%) than MT (73%, P < .001) and TC (56%, P < .001). Mortality rates were comparable between EET (0.6%) and MT (1.6%), but EET had significantly lower mortality than TC (2.7%, P < .001). Compared with MT, EET had lower rates of hypopituitarism (8.5% vs 14.9%, P = .012) but higher rates of diabetes insipidus (3.1% vs 0.5%, P = .001).

CONCLUSION

In an updated meta-analysis of 1413 patients with GPA, EET resection conferred significantly higher rates of visual improvement and GTR, when compared with the MT and TC approaches.

Visual outcomes and optimal timing for repeat surgery in cases of postoperative hematoma following transsphenoidal surgery for pituitary neuroendocrine tumors: A retrospective cohort study

OBJECTIVE

To investigate the visual outcomes and optimal timing for repeat surgery in cases of postoperative hematoma following transsphenoidal surgery for pituitary neuroendocrine tumors (PitNETs).

METHODS

A retrospective study was conducted on 28 patients who developed evident postoperative hematoma out of a total of 9,010 patients. The hematomas were classified into three types based on their CT appearance. Type 1a - mild high density with no tension, Type 1b - thin-layer high density; Type 2a - solid high density with large empty cavities, Type 2b - solid high density with small empty cavities; Type 3 -solid high density with no cavity showing high tension. Patient data were collected for analysis.

RESULTS

The study cohort comprised 10 female and 18 male patients, with a mean age of 51.5±11.9 years. Most patients presented with large adenomas (median diameter 36mm). Postoperative visual sight improved in 12 patients, remained stable in 11 patients, and worsened in 5 patients. Notably, no patients experienced worsened visual sight beyond twenty-four hours after the operation. Among the five patients with visual deterioration, four had CT type 3 hematoma (4/6, 66.7%), and one had CT type 2b hematoma (1/9, 11.1%). Patients in the type 3 CT group were significantly more prone to experience visual deterioration compared to those in the type 2 group (odds ratio [OR] 2.154 [95% CI 1.858-611.014], P=.027). Four patients underwent repeat surgery after visual deterioration, resulting in visual improvement following a prolonged recovery period. Postoperative hematoma had limited impact on pituitary dysfunction and hyponatremia.

CONCLUSION

Our study reveals a significant association between postoperative hematoma CT types and visual deterioration. For patients with stable visual sight and type 1 or 2a hematoma, conservative strategies may be considered. Conversely, type 2b and 3 patients are at higher risk of visual deterioration, especially within the first 24 hours after the operation. Consequently, early reoperation before vision worsens may be a prudent approach to reduce risks and improve visual outcomes, particularly in type 3 patients.

Fat in the Fossa and the Sphenoid Sinus: A Simple and Effective Solution to CSF Leaks in Transsphenoidal Surgery. Cohort Study and Systematic Review

Objectives  Cerebrospinal fluid (CSF) leak following endoscopic transsphenoidal surgery (TSS) remains a challenge and is associated with high morbidity. We perform a primary repair with f at in the pituitary f ossa and further fat in the s phenoid sinus (FFS). We compare the efficacy of this FFS technique with other repair methods and perform a systematic review. Design, Patients, and Methods  This is a retrospective analysis of patients undergoing standard TSS from 2009 to 2020, comparing the incidence of significant postoperative CSF rhinorrhea (requiring intervention) using the FFS technique compared with other intraoperative repair strategies. Systematic review of current repair methods described in the literature was performed following the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. Results  In all, there were 439 patients, with 276 patients undergoing multilayer repair, 68 patients FFS repair, and 95 patients no repair. No significant differences were observed in baseline demographics between the groups. Postoperative CSF leak requiring intervention was significantly lower in the FFS repair group (4.4%) compared with the multilayer (20.3%) and no repair groups (12.6%, p  < 0.01). This translated to fewer reoperations (2.9% FFS vs. 13.4% multilayer vs. 8.4% no repair, p  < 0.05), fewer lumbar drains (2.9% FFS vs. 15.6% multilayer vs. 5.3% no repair, p  < 0.01), and shorter hospital stay (median days: 4 [3-7] FFS vs. 6 (5-10) multilayer vs. 5 (3-7) no repair, p  < 0.01). Risk factors for postoperative leak included female gender, perioperative lumbar drain, and intraoperative leak. Conclusion  Autologous fat on fat graft for standard endoscopic transsphenoidal approach effectively reduces the risk of significant postoperative CSF leak with reduced reoperation and shorter hospital stay.

Disorders of Salt and Water Balance After Pituitary Surgery

Transsphenoidal surgery is the first-line treatment for many clinically significant pituitary tumors and sellar lesions. Although complication rates are low when performed at high-volume centers, disorders of salt and water balance are relatively common postoperatively. Both, or either, central diabetes insipidus (recently renamed arginine vasopressin deficiency - AVP-D), caused by a deficiency in production and/or secretion of arginine vasopressin, and hyponatremia, most commonly secondary to the syndrome of inappropriate antidiuresis, may occur. These conditions can extend hospital stay and increase the risk of readmission. This article discusses common presentations of salt and water balance disorders following pituitary surgery, the pathophysiology of these conditions, and their diagnosis and management.

Postoperative complications after endoscope-assisted transsphenoidal surgery for pituitary adenomas: a case series, systematic review, and meta-analysis of the literature

PURPOSE

Endoscope-assisted transsphenoidal surgery over the last few years has led to more radical excision of pituitary adenomas (PAs) with a low complication rate. Systematic registration of complications by experienced surgical teams could help to improve this technique while ameliorating the patients' quality of life.

MATERIALS AND METHODS

One hundred ten endoscopic procedures were performed in 94 patients with PAs (37 functional) by the same neurosurgical team of a tertiary center during the period 2014-2019. Post-surgical complications were analyzed and compared with data published during the last 5 years in the PubMed and Cochrane databases by performing a systematic review and meta-analysis of the literature.

RESULTS

The overall complication rate in our series was 23.4%. Diabetes insipidus (DI) and intraoperative cerebrospinal fluid (CSF) leakage were the commonest complications (12.8%), followed by postoperative hypopituitarism (9.2%) and hematoma (8.5%) during the follow-up of 2.15 ± 1.4 years. Syndrome of inappropriate antidiuretic hormone secretion, meningitis, deep vein thrombosis, and hyposmia were rare (< 3%). Postoperative hypopituitarism was significantly associated with incidence of hematoma. No statistically significant association was found between PAs Hardy and Knosp scale grading or between patients' characteristics with the occurrence of postoperative complications. Our meta-analysis including nine studies found no significant differences comparing the complications of endoscopic versus microscopic surgery.

CONCLUSION

The endoscopic approach is safe when performed by experienced surgical teams. CSF leakage and DI were the commonest complications in our series; however, confirmation by larger studies is required. Meta-analysis showed no statistically significant differences in complication rates comparing endoscopic versus microscopic surgery.

Equivalent outcomes in nasal symptoms following microscopic or endoscopic transsphenoidal surgery: results from multi-centre, prospective study

Background

T ranssphenoidal surgery (TSS) is the standard approach for resection of pituitary lesions. Historically, this has utilized the microscopic approach (mTSS); however, the past decade has seen widespread uptake of the endoscopic approach (eTSS). The purported benefits of this include improved visualization and illumination, resulting in improved surgical and endocrinological patient outcomes. It is also believed that eTSS results in fewer post-operative nasal symptoms compared to mTSS; however, few papers have directly compared these groups.

Objectives

We sought to compare nasal symptoms after endoscopic uninostril (eTSS-uni), endoscopic binostril (eTSS-bi) and microscopic endoscopic transsphenoidal surgery (mTSS).

Methods

The General Nasal Patient Inventory (GNPI) was prospectively administered to 136 patients (71 non-functioning adenomas, 26 functioning adenomas, 39 other pathology) undergoing transsphenoidal surgery at multiple time points (pre-operatively; days 1, 3 and 7–14; months 1, 3 and 6 and 1 year post-operatively). All surgeries were performed by subspecialist pituitary surgeons in three subgroups — mTSS (25), eTSS-uni (74) and eTSS-bi (37). The total GNPI scores (0–135) and subscores for the 45 individual components were compared across three groups assessing for temporal and absolute changes.

Results

Irrespective of surgical approach used, GNPI scores were significantly higher on post-operative day 1 (p < 0.001) and day 3 (p ≤ 0.03) compared to pre-treatment baseline (mixed-effects model). By 1 month post-operatively, however, post-operative GNPI scores were no different from pre-treatment (p > 0.05, mixed-effects model). Whilst the eTSS-uni group demonstrated significantly lower GNPI scores at day 1 post-op compared to the mTSS group (p = 0.05) and eTSS-bi group (p < 0.001), there was no significant difference in post-operative scores between approaches beyond 1–2 weeks post-operatively. Similar results were obtained when the non-functioning tumour group was analysed separately.

Conclusions

Transsphenoidal pituitary surgery is well tolerated. Post-operative nasal symptoms transiently worsen but ultimately improve compared to pre-operative baseline. Operative approach (microscopic, endoscopic uninostril or endoscopic binostril) only has a transient effect on severity of post-operative nasal symptoms.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00701-022-05138-5.

A Modified Microscopic-Endoscopic Bilateral Transseptal Approach for Pituitary Adenomas: Comparisons of Nasal Outcome and Quality of Life Using the Microscopic Transnasal Approach

OBJECTIVES

In this study, we introduced a novel modified microscopic-endoscopic bilateral transseptal approach for pituitary adenoma resection to minimize surgery-related nasal injury. We also retrospectively compared comprehensive nasal outcomes and quality of life between the microscopic transnasal approaches.

METHODS

Patients with pituitary adenomas who underwent modified microscopic-endoscopic bilateral transseptal or microscopic transnasal approaches were assessed for olfactory function and quality of life using the Sniffin' Sticks test, the Sino-Nasal Outcome Test-22 (SNOT-22), the SF-36, the anterior skull base (ASK) nasal inventory, and the subjective visual analog scale (VAS) before and 1 and 3 months after surgery. A nasal endoscopy procedure was also performed to evaluate structure abnormalities at 1 and 3 months after surgery.

RESULTS

Fifty-eight patients who underwent either modified microscopic-endoscopic bilateral transseptal (35 patients) or microscopic transnasal (23 patients) surgery were consecutively enrolled. Patients who underwent either transnasal approach experienced similar surgical complications, except for intraoperative cerebrospinal fluid leakage (43.5% vs 14.3% for modified microscopic-endoscopic bilateral transseptal or microscopic transnasal approach, respectively; p = 0.013). Patients who underwent the two approaches fully recovered according to the SF-36, SNOT-22, VAS, and Sniffin' Sticks surveys, but not ASK scores, 3 months post-operatively. There was no significant difference in nasal endoscopy outcome at 3 months follow-up between the two approaches.

CONCLUSIONS

The modified microscopic-endoscopic bilateral transseptal approach showed largely similar nasal mucosa protective outcomes to those of the microscopic transnasal approach for pituitary adenoma surgery. After pituitary adenoma resection using the modified approach, patients' postoperative olfactory function, nasal structure, and quality of life can be restored to preoperative status within 3 months.

Endoscopic vs. Microscopic Transsphenoidal Surgery for the Treatment of Pituitary Adenoma: A Meta-Analysis

Purpose

Currently, endoscopic transsphenoidal surgery (ETS) and microscopic transsphenoidal surgery (MTS) are commonly applied treatments for patients with pituitary adenomas. This meta-analysis was conducted to evaluate the efficacy and safety of ETS and MTS for these patients.

Methods

A computer search of Pubmed, Embase, Cochrane library, Web of Science, and Google Scholar databases was conducted for studies investigating ETS and MTS for patients with pituitary adenomas. The deadline is March 01, 2021. RevMan5.1 software was used to complete this meta-analysis after literature screening, data extraction, and literature quality evaluation.

Results

A total of 37 studies including 5,591 patients were included. There was no significant difference in gross tumor removal (GTR) and hormone-excess secretion remission (HES remission) between two groups [RR = 1.10, 95% CI (0.99–1.22), P = 0.07; RR = 1.09, 95% CI (1.00–1.20), P = 0.05]. ETS was associated with lower incidence of diabetes insipidus (DI) [RR = 0.71, 95% CI (0.58–0.87), P = 0.0008], hypothyroidism [RR = 0.64, 95% CI (0.47–0.89), P = 0.007], and septal perforation [RR = 0.32, 95% CI (0.13–0.79), P = 0.01] than those with MTS.

Conclusion

This meta-analysis indicated that ETS cannot significantly improve GTR and HES remission. However, ETS could reduce the incidence of DI, hypothyroidism, and septal perforation without increasing the rate of other complications.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/#myprospero, identifier: CRD42021241217.

Volumetric Resection and Complications in Nonfunctioning Pituitary Adenoma by Fully Endoscopic Transsphenoidal Approach along 15 Years of Single-Center Experience

Objective  The aim of this study was to evaluate the rate of complications and the extent of resection (EOR) of nonfunctioning pituitary adenomas by endoscopic endonasal approach (EEA) in a 15-year learning curve. Methods  A total of 100 patients operated by the same surgical team were divided chronologically into two, three, and four groups, comparing differences in EOR measured by a semiautomatic software (Smartbrush, Brainlab), rate of immediate postoperative complications, and the visual and hormonal status at 6 months. Results  There were no significant differences over the years in rates of postoperative complications and in visual status at 6 months. A significant linear correlation between the EOR and the number of surgeries (rho = 0.259, p  = 0.007) was found. The analysis was performed in three groups because of the remarkable differences among them; the EOR were: 87.2% (early group), 93.03% (intermediate group), and 95.1% (late group) ( p  = 0.019). Gross total resection was achieved in 30.3, 51.5, and 64%, respectively ( p  = 0.017); also, the rate of reoperation and the worsening of at least one new hormonal axis were worse in the early group. Consequently, the early group had a higher risk of incomplete resection compared with the late group (odds ratio: 4.2; 95% confidence interval: 1.5-11.7). The three groups were not different in demographic and volume tumor variables preoperatively. Conclusions  The first 33 interventions were associated with a lower EOR, a high volume of residual tumor, a high reoperation rate, and a higher rate of hormonal dysfunction. We did not find differences in terms of postoperative complications and the visual status at 6-month follow-up.

Growth hormone replacement therapy: is it safe to use in children with asymptomatic pituitary lesions?

OBJECTIVES

Small pituitary cysts are commonly discovered on pediatric brain magnetic resonance imagings (MRIs), particularly in patients with growth hormone deficiency (GHD). We examined the need for operative management in children with these masses as well as the effect of growth hormone replacement (GHR) on these lesions.

METHODS

This was a retrospective review of pituitary protocol MRIs conducted in children 0-19 at a single center between April 2010-November 2020. Sex, indication for initial MRI, volume, and whether surgery was performed was determined. Records were reviewed to determine whether GHD was present and treatment with GHR documented. For patients with subsequent MRIs, volume on most recent scan was calculated.

RESULTS

Of the 101 children with cysts, 25 had laboratory-confirmed GHD and 76 did not. GHD patients had a higher mean age compared to no growth hormone deficiency (NGHD) cohort (11.2 and 8.4 years, respectively; p=0.02) and a larger proportion of males (p<0.001). The mean cyst volume on initial MRI was not significantly smaller in patients with GHD (0.063 ± 0.012 cm³) vs. those without GHD (0.171 ± 0.039 cm³, p=0.11). Of the 21 GHD patients who received GHR and had follow-up MRIs, 10 had no change in pituitary cyst size, two had cysts that shrank, and seven disappeared. The remaining two cysts enlarged an average of 0.061 ± 0.033 cm³. Zero GHR recipients required surgical intervention.

CONCLUSIONS

Small sellar cysts discovered incidentally on imaging in children are unlikely to require surgical intervention. GHR does not appear to significantly enlarge these pediatric pituitary lesions and is safe for use.

Evaluation of the Gross Total Resection Rate of Suprasellar Pituitary Macroadenomas with and without the Removal of the Tuberculum Sellae Bone

OBJECTIVE

Improving the gross total resection (GTR) rate of suprasellar pituitary macroadenomas (SPMAs) using the pure endoscopic endonasal transsphenoidal approach (EETA) has been a long-standing focus of neurosurgeons. This study was aimed at evaluating the influences of the removal of the tuberculum sellae bone (TSB) without opening the dura of the tuberculum sellae on the GTR rate of SPMAs via the EETA.

METHODS

We retrospectively analyzed medical reports of patients with SPMAs who underwent EETA between February 2015 and November 2020. Data on clinical manifestations, endocrinologic types, imaging features (Hardy classification, morphology, and texture), clinical outcomes, and TSB removal status were collected. All patients were followed up for 6 months postoperatively.

RESULTS

Seventy-eight patients were enrolled in our study. The GTR rates of the TSB removal group (45/78, 57.7%) and nonremoval group (33/78, 42.3%) were 80.0% (36/45) and 57.6% (19/33), respectively. Univariate logistic regression analysis found that the removal of TSB, rounded morphology, and low Hardy classification were correlated with higher GTR rates. Multiple logistic regression analysis indicated that even after adjusting for tumor types and imaging features, the removal of TSB had an independent effect on the GTR rate (odds ratio, 7.6; 95% confidence interval, 1.8-31.6; P = 0.005). The incidence rates of postoperative cerebrospinal fluid leakage and diabetes insipidus were not significantly different between the TSB removal group and TSB nonremoval group.

CONCLUSIONS

TSB removal using EETA without opening the tuberculum sellae dura improves the GTR rate of SPMAs without increasing the incidence of postoperative complications.

Pituitary Tumor Surgery: Comparison of Endoscopic and Microscopic Techniques at a Single Center

OBJECTIVE

To understand the transition from microscopic surgery (MS) to endoscopic surgery (ES) on the pituitary across the United States, we assessed a single institution practicing both procedures to discern advantages and disadvantages for each.

PATIENTS AND METHODS

Retrospective institutional chart review of 534 patients in a large practice over a 6-year period (January 1, 2014, to December 31, 2019) comparing a single MS neurosurgeon with a single ES neurosurgeon operating on the same days.

RESULTS

In this series, 14% (n=75) of patients had a prior operation, there were no carotid artery injuries, the overall risk for a postoperative infection was 0.4% (n=2), and risk for a postoperative cerebrospinal fluid leak requiring treatment was 2.0% (n=11). Mean ± SD hospital stay was 1.3±0.04 days; readmission for any reason within 30 days occurred in 3.4% (n=18) of patients. The mean volumetric resection for MS was 86.9%±1.7% and for ES was 91.7%±1.3% (P=.03). There was a higher rate of notable events (P=.015) with MS, but MS had 16% lower cost and operative times were 48 minutes shorter than for ES (83±7 vs 131±6 minutes). The ES required substantially fewer postoperative secondary treatments such as radiation therapy (P=.003).

CONCLUSION

Pituitary surgery is a very safe and effective procedure regardless of technique. The MS has shorter operative times and overall lower cost. The ES results in increased volumetric resection and fewer secondary treatments. Both techniques can be valuable to a large practice, and understanding these niches is important when selecting optimal approaches to pituitary surgery for a given patient.

Comparison of outcomes between endoscopic and microscopic transsphenoidal surgery for the treatment of pituitary adenoma: a meta-analysis

Background

Pituitary tumors are among the most common intracranial tumors. Surgical resection is the most effective treatment for patients with pituitary tumors. Microscopic transsphenoidal surgery has become the first-choice surgical approach to treating this malignancy, although it has certain limitations. Neuroendoscopy has also been widely used for pituitary tumor surgery in recent years. This study aimed to compare the efficacy and safety of these two surgical options for the treatment of pituitary tumors.

Methods

We conducted a literature search of the PubMed, Embase, Cochrane Controlled Center Register of Controlled Trials (CENTRAL), Web of Science database, Google Scholar, and Baidu Scholar. Relevant articles published up to September 25, 2020 were retrieved and then meta-analyzed using RevMan software 5.1.

Results

A total of 29 case-control studies involving 7,774 patients were included in the meta-analysis. There was no significant difference in gross tumor removal (GTR) (RR =1.11, 95% CI: 0.97-1.26, P=0.12) or hormone excess secretion (HES) remission (RR =1.08, 95% CI: 0.97-1.21, P=0.16) between the two groups. Endoscopic transsphenoidal surgery was associated with a lower incidence of diabetes insipidus (DI) than was microscopic transsphenoidal surgery (RR =0.76, 95% CI: 0.60-0.97, P=0.03).

Conclusions

Endoscopic transsphenoidal surgery does not significantly improve GTR or HES remission, but it can reduce the incidence of DI without increasing the rates of other complications.

Trends in endoscopic and microscopic transsphenoidal surgery: a survey of the international society of pituitary surgeons between 2010 and 2020

PURPOSE

This comparative survey of surgical practice patterns between 2010 and 2020 aims to elicit trends in practice patterns for transsphenoidal surgery and to identify areas for improvement.

METHODS

Web-based surveys were sent to the International Society of Pituitary Surgeons via a membership listserv in 2010 and 2020. These 33-item surveys collected information on demographics, surgical approach, perceived advantages and disadvantages, and recommendations for improvements. Statistical analyses were conducted using the Mann-Whitney U test for continuous variables and Fisher's exact test for categorical variables.

RESULTS

There were 51 respondents in 2010 and 82 respondents in 2020. The majority were full-time academic surgeons from the United States or Europe. Preference for a purely endoscopic technique increased from 43% in 2010 to 87% in 2020. Preference for routinely working with an otolaryngologist or second neurosurgeon increased from 35 to 51%. Most surgeons (74%) reported that they were more likely to achieve a greater extent of resection with the endoscope, though 51% noted increased operating time. The most commonly rated advantage (34%) of endoscopic TSS was fewer postoperative nasoseptal perforations; the most commonly (34%) rated disadvantage was more postoperative complications, including cerebrospinal fluid leak. Respondents were divided on whether microscopic TSS should continue to be taught in residency. Many (32%) advocated for improved endoscopic instrumentation and team training.

CONCLUSION

Endoscopic TSS is now the clearly preferred method for surgery amongst a cohort of higher-volume academic neurosurgeons. This trend is likely to continue, and this provides guidelines for future training.

Radiographic and clinical outcomes using intraoperative magnetic resonance imaging for transsphenoidal resection of pituitary adenomas

OBJECTIVE

The utility and safety of intraoperative MRI (iMRI) for resection of pituitary adenomas is not clearly established in the context of advances in endoscopic approaches. The goal in this study was to evaluate the safety and efficacy of iMRI for pituitary adenoma resection, with endoscopic transsphenoidal (ETS) versus microscopic transsphenoidal (MTS) approaches.

METHODS

Radiographic and clinical outcomes of all pituitary adenomas resected using iMRI between 2008 and 2017 at a single institution were retrospectively evaluated.

RESULTS

Of 212 tumors treated, 131 (62%) underwent further resection based on iMRI findings, resulting in a significant increase in gross-total resection on postoperative MRI compared with iMRI (p = 0.0001) in both ETS and MTS groups. iMRI increased rates of gross-total resection for cavernous sinus invasion Knosp grades 1 and 2, but not in Knosp ≥ 3 across treatment groups (p < 0.0001). The extent of resection on postoperative MRI was significantly correlated with increased progression-free survival (p < 0.0001). Initial hormone remission off medical therapy was achieved in 64%, with a significantly higher rate of remission in tumors resected via the ETS approach (81%) compared with the MTS approach (55%) (p = 0.02). The rate of persistent new hormone deficit was low at 8%, including a 2.8% rate of permanent diabetes insipidus, and 45% of patients had improvement in preoperative hormone deficit following surgery. Serious postoperative complications including CSF leaks requiring reoperation were rare at 1%, with no postoperative infections.

CONCLUSIONS

These results suggest that iMRI is a safe and effective method of increasing the extent of resection for pituitary adenomas while preserving hormone function. When paired with the endoscope, iMRI may offer the ability to tailor more aggressive removal of tumors while optimizing pituitary function, resulting in high rates of secretory hormone remission. Secretory tumors and adenomas with Knosp grade < 3 cavernous sinus invasion may benefit most from the use of iMRI.

Endoscopic versus nonendoscopic surgery for resection of pituitary adenomas: a national database study

OBJECTIVE

For symptomatic nonsecreting pituitary adenomas (PAs), resection remains a critical option for treatment. In this study, the authors used a large-population national database to compare endoscopic surgery (ES) to nonendoscopic surgery (NES) for the surgical management of PA.

METHODS

The National Cancer Database was queried for all patients diagnosed with histologically confirmed PA who underwent resection between 2010 and 2016 in which the surgical approach was specified. Due to database limitations, microsurgery and craniotomy were both categorized as NES.

RESULTS

Of 30,488 identified patients, 16,373 (53.7%) underwent ES and 14,115 (46.3%) underwent NES. There was a significant increase in the use of ES over time (OR 1.16, p < 0.01). Furthermore, there was a significant temporal increase in ES approach for tumors ≥ 2 cm (OR 1.17, p < 0.01). Compared to NES, patients who underwent ES were younger (p = 0.01), were treated at academic centers (p < 0.01), lived a greater distance from their treatment site (p < 0.01), had smaller tumors (p < 0.01), had greater medical comorbidity burden (p = 0.04), had private insurance (p < 0.01), and had a higher household income (p < 0.01). After propensity score matching to control for age, tumor size, Charlson/Deyo score, and type of treatment center, patients who underwent ES had a shorter length of hospital stay (LOS) (3.9 ± 4.9 days vs 4.3 ± 5.4 days, p < 0.01), although rates of gross-total resection (GTR; p = 0.34), adjuvant radiotherapy (p = 0.41), and 90-day mortality (p = 0.45) were similar. On multivariate logistic regression, African American race (OR 0.85, p < 0.01) and tumor size ≥ 2 cm (OR 0.89, p = 0.01) were negative predictors of receiving ES, whereas diagnosis in more recent years (OR 1.16, p < 0.01), greater Charlson/Deyo score (OR 1.10, p = 0.01), receiving treatment at an academic institution (OR 1.67, p < 0.01) or at a treatment site ≥ 20 miles away (OR 1.17, p < 0.01), having private insurance (OR 1.09, p = 0.01), and having a higher household income (OR 1.11, p = 0.01) were predictive of receiving ES. Compared to the ES cohort, patients who started with ES and converted to NES (n = 293) had a higher ratio of nonwhite race (p < 0.01), uninsured insurance status (p < 0.01), longer LOS (p < 0.01), and higher rates of GTR (p = 0.04).

CONCLUSIONS

There is an increasing trend toward ES for PA resection including its use for larger tumors. Although ES may result in shorter LOS compared to NES, rates of GTR, need for adjuvant therapy, and short-term mortality may be similar. Factors such as tumor size, insurance status, facility type, income, race, and existing comorbidities may predict receiving ES.

A systematic review of effects and complications after transsphenoidal pituitary surgery: endoscopic versus microscopic approach

Background: Microscopic transsphenoidal surgery (MTS) has been considered as the gold standard for transsphenoidal pituitary surgery, but nowadays endoscopic transsphenoidal surgery (ETS) has become popular due to its wide view and improved lighting.Material and methods: The electronic databases were systematically searched, and the meta-analyses of the eligible studies that evaluated endoscopic versus microscopic methods in patients with pituitary surgery were conducted with Review Manager 5.0. The primary outcomes included visual improvement, gross tumor removal (GTR), cerebrospinal fluid (CFS) leak, diabetes insipidus (DI), other complications, and length of hospital stay. The Egger's test was conducted to estimate possible publication bias.Results: In total, 13 articles eventually met the inclusion criteria. The meta-analyses suggested that the differences with regard to visual improvement, overall complication rate, GTR, CSF leak, diabetes insipidus (DI), meningitis, visual impairment, syndrome of inappropriate antidiuretic hormone secretion (SIADH), new onset hypopituitarism, and hypothyroidism between the endoscopic and microscopic groups were not statistically significant. The length of hospital stay was much longer with the microscopic approach when compared with the endoscopic method.Conclusion: The endoscopic and microscopic approaches show similar effects and complication rates. The endoscopic technique could be adopted as a reasonable alternative in pituitary surgery.

Diabetes insipidus

Diabetes insipidus (DI) is a disorder characterized by excretion of large amounts of hypotonic urine. Central DI results from a deficiency of the hormone arginine vasopressin (AVP) in the pituitary gland or the hypothalamus, whereas nephrogenic DI results from resistance to AVP in the kidneys. Central and nephrogenic DI are usually acquired, but genetic causes must be evaluated, especially if symptoms occur in early childhood. Central or nephrogenic DI must be differentiated from primary polydipsia, which involves excessive intake of large amounts of water despite normal AVP secretion and action. Primary polydipsia is most common in psychiatric patients and health enthusiasts but the polydipsia in a small subgroup of patients seems to be due to an abnormally low thirst threshold, a condition termed dipsogenic DI. Distinguishing between the different types of DI can be challenging and is done either by a water deprivation test or by hypertonic saline stimulation together with copeptin (or AVP) measurement. Furthermore, a detailed medical history, physical examination and imaging studies are needed to ensure an accurate DI diagnosis. Treatment of DI or primary polydipsia depends on the underlying aetiology and differs in central DI, nephrogenic DI and primary polydipsia.

Intra-operative MRI vs endoscopy in achieving gross total resection of pituitary adenomas: a systematic review

BACKGROUND

Intraoperative magnetic resonance imaging (iMRI) is a technology that may improve rates of gross total resection (GTR) for pituitary adenomas. The endoscope is another less expensive technology, which also may maximize resection rates. A direct comparison of these approaches and their additive benefit has never been performed.

METHODS

A systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) standard. PubMed and Embase databases were searched for studies that examined GTR for pituitary adenoma resection with either endoscopic transsphenoidal surgery (eTSS), microscopic transsphenoidal surgery with iMRI (mTSS + iMRI), or endoscopic transsphenoidal surgery with iMRI (eTSS + iMRI).

RESULTS

Eighty-five studies that reported GTR rates in 7124 pituitary adenoma patients were identified. For all pituitary adenomas, eTSS had a pooled proportion of GTR of 68.9% (95% CI 64.7-73.0%) which was similar to that of mTSS + iMRI (GTR 68.3%; 95% CI = 59.4-76.5%) and eTSS + iMRI (GTR 70.7%; 95% CI = 56.9-89.6%). For the subgroup of pituitary macroadenomas, pooled proportions for GTR were similar between eTSS and mTSS + iMRI (eTSS: GTR 59.4%; 95% CI = 49.6-68.7% vs mTSS + iMRI: GTR 68.8%; 95% CI = 57.3-79.3%), and higher for eTSS + iMRI (81.1%; 95% CI = 75.5-86.2%). The post-operative CSF leak proportion for eTSS (4.7%; 95% CI = 3.6-5.9%) was similar to that for eTSS + iMRI (3.7%; 95% CI = 1.6-6.5%) and mTSS + iMRI (4.6%; 95% CI = 2.0-8.3%). No direct statistical comparisons could be performed.

CONCLUSION

Final GTR proportions are similar whether the surgeon uses a microscope supplemented with iMRI or endoscope with or without iMRI. The benefit of the two technologies may be complementary for macroadenomas. These findings are important to consider when comparing the efficacy of different technical strategies in the management of pituitary adenomas.

Sodium Perturbations After Pituitary Surgery

Sodium perturbations are a common complication after pituitary surgery, with hyponatremia being the most frequent. Postoperative assessments should be tailored to the early and late periods, and monitoring sodium perturbations is recommended. Cerebral salt wasting is rare after pituitary surgery, and diagnosis and management can be challenging. Providing patient counseling and close postoperative follow-up is important to effectively manage diabetes insipidus and reduce hospital readmissions due to sodium perturbations.

Neuroendoscopic and microscopic transsphenoidal approach for resection of nonfunctional pituitary adenomas

BACKGROUND

Nonfunctional pituitary adenoma is a common type of pituitary adenoma, which can lead to headache, visual field disturbance, and cranial nerve damage due to increased tumor volume. Neuroendoscopic and microscopic transsphenoidal approaches have been widely used in the resection of nonfunctional pituitary adenomas. However, the clinical efficacy in neuroendoscopic and microscopic surgery is still controversial.

AIM

To explore the clinical efficacy of neuroendoscopic and microscopic transsphenoidal approach for resection of nonfunctional pituitary adenomas.

METHODS

We retrospectively analyzed 251 patients with nonfunctional pituitary adenomas; 138 underwent neuroendoscopic surgery via transsphenoidal approach, and 113 underwent microscopic surgery via transsphenoidal approach between July 2010 and September 2015. All patients were followed up for > 6 mo. Gender, age, course of disease, tumor diameter, tumor location, and percentage of patients with headache, visual impairment, sexual dysfunction, and menstrual disorders were contrasted between the two groups to compare the difference of preoperative data. Cure rate, symptom improvement rate, recurrence rate, the postoperative hospital stay, operating time, intraoperative blood loss, and the incidence of postoperative complications were compared in order to evaluate the advantages and disadvantages of neuroendoscopic and microscopic surgery.

RESULTS

There was no significant difference in cure rate, symptom improvement rate, and recurrence rate between neuroendoscopy group and microscopy group (82.6% vs 85.8%, P > 0.05; 90.6% vs 93.8%, P > 0.05; 5.1% vs 9.7%, P > 0.05). In the neuroendoscopy group, the postoperative hospital stay was 8.4 ± 0.6 d; operating time was 167.2 ± 9.6 min; intraoperative blood loss was 83.4 ± 9.3 mL, and the rates of diabetes insipidus and electrolyte imbalance were 4.3% and 8.0%, respectively. The corresponding results in the microscopic group were 11.2 ± 0.6 d, 199.7 ± 9.3 min, 138.8 ± 13.6 mL, and 32.7% and 20.4%, respectively. There were significant differences in postoperative hospital stay, operating time, intraoperative blood loss, and the rates of diabetes insipidus and electrolyte imbalance between the two groups (P < 0.05).

CONCLUSION

Neuroendoscopic and microscopic transsphenoidal approaches have similar clinical efficacy for the resection of nonfunctional pituitary adenomas. Neuroendoscopic surgery reduces operating time, intraoperative bleeding, postoperative recovery, and complications.

Clinical utility of routine postoperative morning cortisol monitoring in detecting new hypothalamic-pituitary-adrenal axis insufficiency following endoscopic transsphenoidal surgery for sellar lesions

OBJECTIVE

Hypothalamic-pituitary-adrenal (HPA) axis dysfunction is a well-documented complication of transsphenoidal craniotomy (TSC) for sellar lesions. The authors aimed to assess their multidisciplinary approach to the diagnosis and treatment of postoperative hypocortisolemia utilizing conservative screening methods.

METHODS

The authors performed a retrospective review of 257 patients who underwent TSC for pituitary adenoma (PA) or Rathke cleft cyst (RCC) at the University of Southern California between 2012 and 2017. Patients with preoperative adrenal insufficiency, Cushing's disease, or < 3 months of postoperative follow-up were excluded. Patient demographics, pathology, tumor characteristics, and complications were recorded. Postoperative day 1 (POD1) morning serum cortisol was assessed in all patients. Hypocortisolemia on POD1 (serum cortisol < 5 μg/dl) prompted a 7 am cortisol level measurement on POD 2 (POD2). Clinical signs and symptoms of hypocortisolemia were consistently monitored. After two serum cortisol levels < 5 μg/dl, or one serum level < 5 μg/dl plus a high clinical suspicion for HPA dysfunction, high-risk patients received glucocorticoid supplementation.

RESULTS

Data on 165 patients were included in the analysis; there were 101 women (61.2%) and 64 men (38.7%). Preoperative diagnoses included nonfunctional adenoma (n = 97, 58.7%), growth hormone-secreting adenoma (n = 37, 22.4%), RCC (n = 18, 10.9%), prolactinoma (n = 8, 4.8%), and other (n = 5, 3.0%). One hundred thirty-eight patients (63.0%) had either suprasellar extension or cavernous sinus invasion. POD1 hypocortisolemia was diagnosed in 8 patients (4.8%). Of these patients, 2 (1.2%) were clinically asymptomatic and had normalized POD2 cortisol levels. Six patients (3.6%) had clinical symptoms and POD2 cortisol levels confirming HPA axis deficiency. Of these 6 patients treated with early glucocorticoid replacement, 2 patients recovered HPA axis function during follow-up, making the incidence of new, permanent HPA axis deficiency 2.5%.

CONCLUSIONS

In the authors' institutional review, all patients warranting postoperative glucocorticoid replacement had both complicated surgical courses and associated clinical symptoms of hypocortisolemia. The authors' algorithm of withholding steroids until patients demonstrate clear evidence of postoperative hypocortisolemia is safe and clinically efficacious. Their data further suggest that routine postoperative cortisol screening may not be necessary following an uncomplicated operative resection, with gland preservation and the absence of clinical symptoms indicative of HPA dysfunction.

Degrees of Diaphragma Sellae Descent during Transsphenoidal Pituitary Adenoma Resection: Predictive Factors and Effect on Outcome

This study is aimed to classify degrees of diaphragma sellae (DS) descent into sella turcica according to the surgical field block caused by the descent and to construct predictive imaging criteria for the degree of descent, and in addition, to determine whether there is any correlation between the degree of DS descent and the operative outcome (in the form of cerebrospinal fluid leak and/or presence of residual tumor). Totally, 72 patients were enrolled in our study. Their clinical and radiological data as well as the high definition videos of operations were retrospectively reviewed. The degree of DS descent during the operation was classified into five degrees according to surgical field block caused by the descent. We investigated the correlation between these five degrees and the clinical findings, radiological findings as well as the surgical outcomes. We found that the most important determining factors of DS descent degree were the volume and the height of the tumor portion above diaphragma opening. On the other hand, the total tumor volume, the maximum tumor height and the morphological pattern according to Wilson's system (modified from Hardy) had no statistically significant correlation with DS degree of descent. Presence of residual tumor on postoperative magnetic resonance images was significantly correlated with Wilson's classification and with supradiaphragmatic tumor height. On the other hand, cerebrospinal fluid leak showed no statistically significant difference between variable degrees of DS descent. Volumetric data of the tumor portion above the diaphragma opening are more important than morphological data for prediction of surgical field block caused by descended DS. While DS prolapse significantly increases the difficulty of the operative procedure, residual tumor presence is mainly dependent on morphological classification, especially cavernous sinus invasion.