Microscopic versus endoscopic transnasal pituitary surgery

The Impact of Endoscopic Endonasal Surgery on Quality of Life in Patients with Malignant Tumors of the Anterior Skull Base: A Prospective Study

Objective

To investigate the effects of endoscopic endonasal surgery (EES) on longitudinal quality of life (QoL) in patients with malignant tumors of the anterior skull base.

Methods

Eligible patients prospectively completed the Anterior Skull Base Surgery Questionnaire (ASBQ) and the 22-item Sino-Nasal Outcome Test (SNOT-22) questionnaires in referring to 3 different periods throughout their treatment and recovery.

Results

Forty patients were included. The median volume coronal maximum length of the tumor was 3.6 cm (95% CI 2.7-4.1cm). Overall QoL significantly worsened at 1 month postoperatively but returned to baseline after 1 year. Unrelieved symptoms in specific domains prompted further evaluation of individual items. Transient worsening of taste (p=0.011) and olfaction (p=0.004) lasted for 1 month but gradually relieved within the first postoperative year, but vision consistently worsened over the course of the treatment (p=0.126). Age>50 years (p<0.001), comorbidities (p<0.001), tumor necrosis (p<0.001) and recurrence (p=0.001) were associated with worse preoperative QoL. Poor long-term QoL was noted in those undergoing adjuvant therapy (p=0.032). Overall ASBQ scores (p=0.024), subdomain scores in specific symptoms (p=0.016), and vision scores (p=0.009) were worse only in patients with the greater coronal maximum diameter at 1-month postoperatively. Greater coronal maximum diameter was related to worse preoperative subdomain scores regarding specific symptoms (p=0.030) and decreased postoperative long-term decreased vision scores (p=0.014).

Conclusion

Long-term site-specific and sinonasal QoL eventually stabilized after EES. Greater coronal maximum diameter was significantly associated with worsened vision function. Temporarily worse olfactory, vision, and taste function may be tied to decreased short-term QoL.

The Benefit of Intraoperative Magnetic Resonance Imaging in Endoscopic and Microscopic Transsphenoidal Resection of Recurrent Pituitary Adenomas

The surgical treatment of recurrent adenomas can be challenging. Intraoperative magnetic resonance imaging (iMRI) can improve the orientation and increase the safe extent of resection. We conducted a quantitative and qualitative retrospective analysis of recurrent adenomas treated by endoscopic or microscopic iMRI-assisted transsphenoidal surgery. A total number of 59 resections were selected. Detailed volumetric measurements, tumor characteristics, and MRI features of intraoperative remnants were evaluated. Intraoperative MRI increased the gross total resection (GTR) rate from 33.9% to 49.2%. Common locations of tumor remnants after iMRI were the clivus, the wall of the cavernous sinus or the perforation of the diaphragm. Increasing tumor volume and the microscopic technique were significantly associated with further resection after iMRI in the univariate analysis (p = 0.004, OR 1.6; p = 0.009, OR 4.4). Only the increasing tumor volume was an independent predictor for further resection (p = 0.007, OR 1.5). A significantly higher proportion of GTRs was achieved with the endoscopic technique (p = 0.001). Patients with a large recurrent pituitary adenoma who underwent microscopic transsphenoidal resection were the most likely to benefit from iMRI regarding the extent of resection. Occult invasions of the cavernous sinus and/or the clivus were the most common findings leading to further resection of tumor remnants after iMRI.

Characterization of tumor remnants in intraoperative MRI-assisted microscopic and endoscopic transsphenoidal resection of less invasive pituitary adenomas

INTRODUCTION

Intraoperative magnetic resonance imaging (iMRI) improves the intraoperative detection of adenoma remnants in transsphenoidal surgery. iMRI might be redundant in endoscopic pituitary surgery in non-invasive tumors (Knosp 0-2) due to a superior visualization of anatomical structures in the periphery of the sella turcica compared to the microscopic technique. We identified the anatomical location of tumor remnants in iMRI and evaluated risk factors for secondary resection after iMRI and hereby selected patients with pituitary adenomas who may benefit from iMRI-assisted resection.

METHODS

We conducted a retrospective monocenter study of patients who underwent iMRI-assisted transsphenoidal surgical resection of pituitary adenomas at our department between 2012 and 2020. A total number of 190 consecutive iMRI-assisted transsphenoidal surgeries of pituitary adenomas graded as Knosp 0-2 were selected for analysis. Exclusion criteria were missing iMRI availability or pathologies other than adenomas. Of these 190 cases, 46.3% (N = 88) were treated with microscopic, 48.4% (N = 92) with endoscopic, and 5.3% (N = 10) with endoscopic-assisted technique. Volumetric measurement of preoperative, intraoperative, and postoperative tumor extension was performed. Demographic data, tumor characteristics, and MRI features were evaluated. Additionally, analysis of adenoma remnants identified by iMRI was performed.

RESULTS

An additional resection after iMRI was performed in 16.3% (N = 31). iMRI helped to reach gross total resection (GTR) in 83.9% (26/31) of these cases. False-positive resection was found in 1 patient (0.5%). Multivariable logistic analysis identified tumor volume (OR = 1.2, p = 0.007) recurrence (OR = 11.3, p = 0.002) and microscopic technique (OR = 2.8, p = 0.029) as independent risk factors for additional resection. Simultaneously, the endoscopic technique was significantly associated with GTR as evaluated by iMRI (OR = 2.8, p = 0.011) and postoperative MRI (OR = 5.8, p = 0.027). The detailed analysis of adenoma remnants on iMRI revealed the suprasellar location in a diaphragm fold, penetrating tumor above the diaphragm, or undetected invasion of cavernous sinus as well as in case of microscopic resection tumor location outside the line of sight as the main reasons for incomplete resections.

CONCLUSION

Tumor volume, recurrence, and microscopic technique were identified as independent predictors for additional resection in patients with Knosp 0-2 adenomas. iMRI might increase the extent of resection (EOR) safely even after the endoscopic visualization of the sella with very low risk for false-positive findings. Remnants of tumors hidden within the diaphragmic folds, intrathecally, or behind the infiltrated wall of cavernous sinus not recognized on preoperative MRI were the most common findings in iMRI.

Three-Dimensional Endoscopic Endonasal Surgery: A Systematic Review

OBJECTIVES

To compare participant performance and preference in the use of three-dimensional (3D) endoscopy compared to traditional two-dimensional (2D) endoscopy.

METHODS

PubMed, Embase, Medline, ClinicalKey, BMJ Case Reports, and the Cochrane library were systematically searched for English-language articles published between 2005 and 2020. Studies reporting comparisons of outcomes between 3D and 2D endoscopes were identified. Data relating to performance-related outcomes, as well as the participants' preferred endoscope were extracted, and pooled using meta-analysis models.

RESULTS

Ten studies were included in the qualitative synthesis. Six studies reported results of participants completing simulated tasks with endoscopes, while four reported full procedures. Peg transfer tasks (n = 4 cohorts) were found to be completed significantly faster with the 3D versus 2D endoscope (pooled mean difference 6.8 seconds, 95% confidence interval [CI]: 2.3-11.3), while no significant difference in times taken was observed for touch tasks (n = 4; pooled mean difference 3.7 seconds, 95% CI: -1.9 to 9.2). The secondary outcome of participant preference was reported by five studies, in which a significant preference for the 3D endoscope was observed (P = .010), with a pooled total of 72% (95% CI: 59-83) of participants preferring this to the 2D endoscope.

CONCLUSIONS

There is a growing body of evidence in support of 3D visualization in endoscopy. We have demonstrated 3D endoscopy to be associated with a significantly shorter time to performing simulated, reproducible and controlled tasks, and to be the preference of participants. This study provides grounds for further evaluation of the technology, and the potential for a greater widespread use. Laryngoscope, 2021.

Endoscopic approach for giant pituitary adenoma: clinical outcomes of 205 patients and comparison of two proposed classification systems for preoperative prediction of extent of resection

OBJECTIVE

Giant pituitary adenoma is considered a challenging pathology for surgery owing to its complications and low resection rate. In this study, the authors present their experience of using the endoscopic endonasal approach to treat patients with giant pituitary adenoma, and they aimed to develop a classification system for prediction of extent of resection.

METHODS

The institutional medical records of patients diagnosed with giant pituitary adenoma who underwent endoscopic endonasal transsphenoidal surgery between August 1997 and December 2019 were retrospectively reviewed. Surgical and clinical outcomes were evaluated in detail. The effects of tumor characteristics on extent of resection were analyzed. The findings were used to develop two classification systems that could preoperatively predict extent of resection. Morphological score was based on tumor characteristics, and landmark-based classification was defined according to surgical zones based on neurovascular landmarks. The effects of change in surgical strategy, which aimed to maximize tumor resection and capsule dissection, on rates of resection and complications were evaluated before and after 2017.

RESULTS

This study included 205 patients, with a mean patient age of 46.95 years and mean preoperative tumor diameter of 46.56 mm. Gross-total resection (GTR) was achieved in 35.12% of patients, near-total resection (NTR) in 39.51%, and subtotal resection (STR) in 25.36%. Extent of resection differed significantly between the grades and zones of the classification systems (p < 0.001 for both). Among patients with grade 3 tumor, 75.75% of patients achieved STR, 21.21% achieved NTR, and 3.03% achieved GTR. Among patients with zone 3 tumor, 65.75% achieved STR, 32.87% achieved NTR, and 1.36% achieved GTR. Both grade 3 and zone 3 indicated limited extent of resection. The mean (range) follow-up duration was 50.16 (9-247) months. Postoperative recovery of at least one hormone axis was seen in 15.24% of patients with pituitary deficiency, and development of new hormonal deficiency was observed in 22.43% of patients. Complications included permanent diabetes insipidus (7.80%), cerebrospinal fluid leakage (3.90%), postoperative apoplexy (3.90%), meningitis (3.41%), and epistaxis (3.41%). The surgical mortality rate was 1.46%. Among 85 patients treated before 2017, 27.05% of patients achieved GTR, 37.64% achieved NTR, and 35.29% achieved STR; among 120 patients treated after 2017, 40.83% achieved GTR, 40.83% achieved NTR, and 18.33% achieved STR. Seven patients in the pre-2017 cohort had postoperative apoplexy versus only 1 patient in the post-2017 cohort. There were no statistically significant differences between the two periods in terms of the incidence rates of other complications.

CONCLUSIONS

Capsule dissection and GTR are valuable for preventing serious complications and reducing recurrence of giant adenoma. Treatment of giant pituitary adenoma may be better managed with the help of a classification system that provides information about extent of resection that can be achieved with an endoscopic approach.

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.

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.

Pituitary Hormonal Status after Endoscopic Endonasal Transphenoidal Removal of Nonfunctioning Pituitary Adenoma: 5 years' Experience in a Single Center

Background

This study focuses on hormonal disorder and medical complications postoperative endoscopic endonasal transsphenoidal approach of nonfunctioning adenoma at Prasat Neurological Institute, Bangkok, between January 2013 and December 2017.

Methods and Material

Baseline characteristics, clinical complications, and hormonal status data were collected from the patients' medical records and analyzed using the descriptive statistics.

Results

There were four surgeons who operated 126 cases, 17 of them were reoperation. The average age of the patients was 49 years old. The average length of stay was 13 days, and average operating time was 134 min. Visual field defect was the most common presenting symptom. Almost all the tumors were classified as pituitary macroadenoma which invaded one or two sellar walls. Total or near total tumor removal was the most extend of resection. There were 61 cases developed early diabetes insipidus (DI), but only 12 cases continue to long-term DI. Seven cases were meningitis. Three cases were death. Out of 83 patients who had preoperative intact hypothalamic-pituitary-adrenal (HPA) axis and hypothalamic pituitary thyroidal (HPT) axis, 2 and 3 of them developed postoperative impair HPA and HPT axis in that order. In addition, among 45 patients who had preoperative impair HPA and HPT axis, 6 of them achieved postoperative endocrinological normalization.

Conclusion

In preoperative intact pituitary hormone patients, the total or near total tumor removal of non functioning pituitary adenoma may have hypopituitarism during early postoperative period but gradually returned to normal during 4-6 month postoperative period.

Multilayered Artificial Dura-Mater Models for a Minimally Invasive Brain Surgery Simulator

In this study, new artificial dura-mater models were developed using a multilayered structure of a rubber material (represent an elastic component of a dura-mater) and a fiber sheet (represent fiber component of a dura-mater). The artificial dura-mater models were prepared for use in a brain surgery simulator, especially for transnasal pituitary surgery. The mechanical characteristics of the artificial dura-mater models were tested to check the similarities with porcine dura-mater. Tensile stress, viscoelasticity, and the cutting force generated by microscissors were tested to evaluate the fabricated models. Neurosurgeons also assessed the dura-mater models to evaluate their characteristics. The results indicate that these models made of two different non-woven fiber sheets emulated accurately the actual dura-mater.

Readmission after endoscopic transsphenoidal pituitary surgery: analysis of 584 consecutive cases

OBJECTIVE

Hospital readmission is a key component in value-based healthcare models but there are limited data about the 30-day readmission rate after endonasal endoscopic transsphenoidal surgery (EETS) for pituitary adenoma. The objective of this study was to determine the incidence and identify factors associated with 30-day readmission after EETS for pituitary adenoma.

METHODS

The authors analyzed a prospectively acquired database of patients who underwent EETS for pituitary adenoma from 2005 to 2018 at NewYork-Presbyterian Hospital, Weill Cornell Medicine. Clinical, socioeconomic, and radiographic data were reviewed for cases of unplanned readmission within 30 days of surgery and, as a control group, for all other patients in the series who were not readmitted. Statistical significance was determined with an alpha < 0.05 using Pearson's chi-square and Fisher's exact tests for categorical variables and the independent-samples t-test for continuous variables.

RESULTS

Of 584 patients undergoing EETS for pituitary adenoma, 27 (4.6%) had unplanned readmission within 30 days. Most readmissions occurred within the first week after surgery, with a mean time to readmission of 6.6 ± 3.9 days. The majority of readmissions (59%) were for hyponatremia. These patients had a mean sodium level of 120.6 ± 4.6 mEq/L at presentation. Other causes of readmission were epistaxis (11%), spinal headache (11%), sellar hematoma (7.4%), CSF leak (3.7%), nonspecific headache (3.7%), and pulmonary embolism (3.7%). The postoperative length of stay was significantly shorter for patients who were readmitted than for the controls (2.7 ± 1.0 days vs 3.9 ± 3.2 days; p < 0.05). Patients readmitted for hyponatremia had an initial length of stay of 2.6 ± 0.9 days, the shortest of any cause for readmission. The mean BMI was significantly lower for readmitted patients than for the controls (26.4 ± 3.9 kg/m2 vs 29.3 ± 6.1 kg/m2; p < 0.05).

CONCLUSIONS

Readmission after EETS for pituitary adenoma is a relatively rare phenomenon, with delayed hyponatremia being the primary cause. The study results demonstrate that shorter postoperative length of stay and lower BMI were associated with 30-day readmission.

Incidence and risk factors associated with reoperation for sellar hematoma following endoscopic transsphenoidal pituitary surgery

OBJECTIVE

Postoperative sellar hematoma is an uncommon complication of endonasal endoscopic transsphenoidal surgery (EETS) for pituitary adenoma that often requires emergency surgical evacuation. Sellar hematomas can cause mass effect and compress parasellar structures, leading to clinically significant symptoms such as visual impairment and severe headache. The objective of this study was to determine the incidence and risk factors associated with reoperation for postoperative hematoma after EETS for pituitary adenoma.

METHODS

The authors reviewed a prospectively acquired database of EETS for pituitary adenoma over 13 years at Weill Cornell Medicine, NewYork-Presbyterian Hospital and identified cases that required reoperation for confirmed hematoma. They also reviewed clinical and radiographic data of a consecutive series of patients undergoing EETS for pituitary adenoma who did not have postoperative hematoma, which served as the control group. Demographic data and risk factors were compared between the groups using univariate and multivariate analyses via binary logistic regression.

RESULTS

Among a cohort of 583 patients undergoing EETS for pituitary adenoma, 9 patients (1.5%) required operation for sellar hematoma evacuation. All 9 patients with reoperation for sellar hematoma presented with worsening in their vision, and severe headache was present in 67%. New postoperative endocrine dysfunction developed in 78%. Clot evacuation improved vision in 88%. The mean time to hematoma evacuation was 4.5 days. The median length of stay for patients with sellar hematoma was 8 days (range 4-210 days) compared with a median length of stay of 3 days (range 1-32 days) for the control patients (p < 0.005). Significant risk factors in univariate analysis were tumor diameter ≥ 30 mm (p < 0.005), suprasellar extension (p < 0.005), tumor volume (p < 0.005), cavernous sinus invasion (p < 0.05), gonadotroph histology (p < 0.05), antiplatelet use (p < 0.05), and elevated BMI (p < 0.05). On multivariate analysis, tumor diameter ≥ 30 mm (OR 4.555, CI 1.30-28.90; p < 0.05) and suprasellar extension (OR 1.048, CI 1.01-1.10; p < 0.05) were found to be the only independent predictors of sellar hematoma. The incidence of hematoma in tumors ≥ 30 mm was 5% (7/139).

CONCLUSIONS

Postoperative sellar hematoma requiring reoperation is a rare phenomenon after transsphenoidal surgery, often presenting with visual loss and headache. Clot evacuation results in improvement in vision, but long-term endocrinopathy often ensues. Tumor diameter ≥ 30 mm and suprasellar extent are the most reliable risk factors. Close postoperative scrutiny should be given to patients at high risk.

Drivers of In-Hospital Costs Following Endoscopic Transphenoidal Pituitary Surgery

OBJECTIVE

To characterize the patient and clinical factors that determine variability in hospital costs following endoscopic transphenoidal pituitary surgery.

METHODS

All endoscopic transphenoidal pituitary surgeries performed from January 1, 2015, to October 24, 2017, with complete data were evaluated in this retrospective single-institution study. The electronic medical record was reviewed for patient factors, tumor characteristics, and cost variables during each hospital stay. Multivariate linear regression was performed using Stata software.

RESULTS

The analysis included 190 patients and average length of stay was 4.71 days. Average total in-hospital cost was $28,624 (95% confidence interval $25,094-$32,155) with average total direct cost of $19,444 ($17,136-$21,752) and total indirect cost of $9181 ($7592-$10,409). On multivariate regression, post-operative cerebrospinal fluid (CSF) leak was associated with a significant increase in all cost variables, including a total cost increase of $40,981 ($15,474-$66,489, P = .002). Current smoking status was associated with an increased total cost of $20,189 ($6,638-$33,740, P = .004). Self-reported Caucasian ethnicity was associated with a significant decrease in total cost of $6646 (-$12,760 to -$532, P = .033). Post-operative DI was associated with increased costs across all variables that were not statistically significant.

CONCLUSIONS

Post-operative CSF leak, current smoking status, and non-Caucasian ethnicity were associated with significantly increased costs. Understanding of cost drivers of endoscopic transphenoidal pituitary surgery is critical for future cost control and value creation initiatives.

LEVEL OF EVIDENCE

3 Laryngoscope, 131:760-764, 2021.

Ten years’ experience with intraoperative MRI-assisted transsphenoidal pituitary surgery

OBJECTIVE

Many innovations have been introduced into pituitary surgery in the quest to maximize the extent of tumor resection. Because of the deep and narrow surgical corridor as well as the heterogeneity of confronted pathologies, anatomical orientation and identification of the target tissue can become difficult. Intraoperative MRI (iMRI) may have the potential to increase extent of resection (EOR) in transsphenoidal pituitary surgery. Furthermore, it may simplify anatomical orientation and risk assessment in difficult cases. Here, the authors evaluated the additional value of iMRI for the resection of pituitary adenomas performed in the past 10 years in their department.

METHODS

They performed a retrospective single-center analysis of patients treated for pituitary adenoma in their department after the introduction of iMRI between 2008 and 2018. Of 495 transsphenoidal approaches, 300 consecutive MRI-assisted surgeries for pituitary adenomas encompassing 294 patients were selected for further analysis. Microscopic, endoscopic, or endoscope-assisted microscopic transsphenoidal approaches were distinguished. EOR as well as additional resection following iMRI was evaluated via detailed volumetric analysis. Patients were stratified according to the Knosp adenoma classification. Furthermore, demographic data, clinical symptoms, endocrine outcome, and complications were evaluated. Univariable and multivariable Cox regression analyses of progression-free survival (PFS) were performed.

RESULTS

Pituitary adenomas classified as Knosp grades 0–2 were found in 60.3% of cases (n = 181). The most common tumors were nonfunctioning adenomas (75%). Continued resection following iMRI significantly increased EOR (7.5%, p < 0.001) and the proportion of gross-total resections (GTRs) in transsphenoidal pituitary surgery (54% vs 68.3%, p < 0.001). Additional resection after iMRI was performed in 37% of cases. Only in the subgroup of patients with Knosp grades 0–2 adenomas treated with the microsurgical technique was additional resection significantly more common than in the endoscopic group (p = 0.039). Residual tumor volume, Knosp grade, and age were confirmed as independent predictors of PFS (p < 0.001, p = 0.021, and p = 0.029, respectively) in a multivariable Cox regression analysis. Improvement of visual field deficits was documented in 78.6% of patients whose optic apparatus had been affected preoperatively. Revision surgery was done in 7.3% of cases; in 5.6% of cases, it was performed for cerebrospinal fluid fistula.

CONCLUSIONS

In this series, iMRI led to the detection of a resectable tumor remnant in a high proportion of patients, resulting in a greater EOR and higher proportion of GTRs after continued resection in microsurgical and endoscopic transsphenoidal resection of pituitary adenomas. The volume of residual tumor was the most important predictor of PFS. Given the study data, the authors postulated that every bit of removed tumor serves the patient and increases their chances of a favorable outcome.

Olfactory outcomes after transsphenoidal endonasal surgery

Background: The endonasal approach is the gold standard for the resection of pituitary tumours, with either microscopic endonasal transsphenoidal (MET) or endoscopic endonasal transsphenoidal (EET) technique. Advantages and disadvantages of both techniques have been widely described in the literature, although limited attention has been paid to its impact on the sense of smell.Objective: The present study aims to quantify the effect of transnasal surgery on pituitary patients and examine olfactory outcomes.Methods: A prospective cohort study assessing the sense of smell of 20 patients (10 MET and 10 EET) pre-operatively. Olfactory function was re-assessed 6 months after surgery, using the University of Pennsylvania Smell Identification Test (Sensonics Inc., Haddon Heights, NJ).Results: The UPSIT (Sensonics Inc.) results showed a median pre-operative score of 33 (IQR 31-37.5) (normosmia). The median post-operative result was 25 (IQR 19.5-32), consistent with moderate microsmia. Twenty percent of the patients had normal olfactory function post-operatively, all of whom were from the EET group. Twenty percent had mild microsmia, equally divided in MET and EET subgroups. Seven patients had severe microsmia. Four patients were completely anosmic at 6 months follow-up.Conclusions: Patients undergoing a transsphenoidal procedure are at risk of olfactory disturbance post-operatively, which may include loss of the sense of smell. This information is relevant to the patients' perioperative experience, and should be incorporated into counselling with regards to outcomes and expectations. Although the study size is small, the study results suggest the ETS technique may be less traumatic for the olfactory function. A larger study powered to fully examine potential differences in olfactory outcomes following ETS and MTS is warranted.

Beyond the Learning Curve: Comparison of Microscopic and Endoscopic Incidences of Internal Carotid Injury in a Series of Highly Experienced Operators

BACKGROUND

As the endoscopic endonasal approach (EEA) has gained popularity as an alternative to microsurgery (MS) for transsphenoidal resection (TSR), numerous studies have attempted to assess the differential risk of internal carotid artery (ICA) injury between the techniques, yet results have been equivocal and contradictory. The aim of this study was to evaluate ICA injury in MS versus EEA among highly experienced neurosurgeons.

METHODS

We performed a systematic literature review of publications from 2002-2017 reporting ICA injury outcomes in ≥250 cases using MS or EEA.

RESULTS

Seventeen series reporting 11,149 patients were included: 3 MS series, 13 EEA series, and 1 series with adequate samples for each. ICA injury incidences were 0.0%-1.6% in cohorts of 275-3000. MS series documented 5 ICA injuries in 2672 operations, for an overall incidence of 0.2% (range, 0.0%-0.4%), and EEA series reported 30 ICA injuries in 8477 operations, for a 0.4% injury rate (range, 0.0%-1.6%); the difference was nonsignificant (P = 0.25). Increased operative experience was associated with decreased incidence of ICA injury, a finding preserved in the overall study cohort and within discretely examined MS and EEA subgroups (overall r² = 0.08, MS r² = 0.23, EEA r² = 0.07).

CONCLUSIONS

ICA injury is the most serious complication of TSR of pituitary neoplasms. Operator inexperience may be a more important risk factor than choice of surgical technique, given the comparably low rates of injury obtained by highly experienced surgeons independent of technique. This emphasizes the need for consolidated care in pituitary centers of excellence, improvement of high-fidelity simulators, and skull base mentorship between senior and junior staff.

An alternative technique for pituitary tumour removal: Sequential endoscopic-microscopic pituitary procedure (SEMPP)

Several authors have reported advantages of the purely endoscopic (PE) approach over traditional purely microscopic (PM) techniques for many sinus and anterior skull base procedures. However, in pituitary surgery, the PE approach carries a number of limitations. Experienced microscopically-trained neurosurgeons are required to master the endoscopic technique which has a steep learning curve due to its one-handed nature and optically-distorted 2-dimensional view. We describe our novel technique, the sequential endoscopic and microscopic pituitary procedure (SEMPP) which does not require microscopically-trained neurosurgeons to alter their technique. We compare SEMPP with the PE approach in terms of outcome and safety. Retrospective chart review of consecutive SEMPP cases performed at our institution between January 2010 and December 2013 was conducted. Operative time, gross total resection rate, resolution of endocrine and visual dysfunction, hospital length of stay, cerebrospinal fluid (CSF) leak rate and revision rates were recorded. 32 patients were identified (50% female, mean age 53.0 years), and 33 SEMPP cases. Mean operating time was 132 min (range 90-200). 69% of patients experienced gross total resection. Most patients (81.3%) with preoperative visual deficit either experienced complete resolution or improved symptoms. The remainder experienced no change in vision. 12.5% (n = 4) of patients experienced intraoperative CSF leaks. All were repaired intraoperatively or with conservative management. Two patients (6.3%) experienced epistaxis managed with conservative measures. The SEMPP technique demonstrates comparable outcomes, complication rates and operative time to PE and PM techniques described in the literature.

Breadth and Depth: Three-Dimensional Endoscopic Field of View: Two-Dimensional Versus Three-Dimensional Endoscopic Field of View

BACKGROUND

Three-dimensional (3D) endoscopy is an emerging tool in ear-nose-throat (ENT) and skull base surgery with the benefit of providing real-time depth perception. Several investigators have reported that the field of view (FOV) is reduced in 3D endoscopes compared with regular 2-dimensional (2D) endoscopes. Thus, we objectively compared the FOV of 2D and 3D endoscopes.

METHODS

Using a standard 2D and 2 different 3D ENT endoscopes, images were captured of 1-mm graph paper from a set distance of 6 cm. The FOV was calculated from these images and compared among the endoscopes.

RESULTS

The VisionSense 3D endoscope had a slightly smaller FOV (9.1 cm vs. 10.1 cm; -9.9%), and the Karl Storz 3D endoscope showed a slightly larger FOV (10.4 cm vs. 10.1 cm; +3.0%). However, the results were complicated by the different-shaped images produced by the 3D endoscopes.

CONCLUSION

The differences in the FOV between the 2D and 3D endoscopes used in ENT surgery were not clinically significant. Thus, the FOV should not be considered a limitation of 3D technology.

Technological and Ideological Innovations in Endoscopic Skull Base Surgery

BACKGROUND

Endoscopic skull base surgery has evolved over the last several decades due to technological advances and operative techniques. Several innovations that are not yet mainstream may have significant impact on the future of endoscopic skull base surgery.

METHODS

Current literature pertaining to innovations in endoscopic skull base surgery was retrieved using PubMed, Embase, Web of Science, and Google Scholar.

RESULTS

Several recent innovations may play an influential role in the advancement of endoscopic skull base surgery, including fluorescent dyes such as indocyanine green fluorescence, fluorescein, and 5-aminolevulinic acid, 3-dimensional endoscopes, robotic surgery, and intraoperative magnetic resonance imaging.

CONCLUSIONS

Several technologies are under current investigation with the hope to improve future outcomes in endoscopic skull base surgery. Additional research and evolution are necessary and will require intense scrutiny before becoming standard of care.

Three-dimensional endoscopy: The future of nasoendoscopic training

OBJECTIVES/HYPOTHESIS

Three-dimensional (3D) endoscopy is an emerging tool in surgery that provides real-time depth perception. Its benefits have been investigated in surgical training, but the current literature lacks significant objective outcome data. We aimed to objectively compare the efficacy of two-dimensional (2D) versus 3D high-definition endoscopes in novice users.

STUDY DESIGN

Prospective, randomized crossover study.

METHODS

Ninety-two novice medical students who used both 2D and 3D endoscopes to complete two validated tasks in a box trainer participated in the study. Time taken and error rates were measured, and subjective data were collected.

RESULTS

Wilcoxon tests showed 3D technology was significantly faster than 2D (78 vs. 95 seconds, P = .004), and errors per task were significantly lower (3 vs. 5, P < .001). Sixty-nine percent of participants preferred the 3D endoscope.

CONCLUSIONS

3D high-definition endoscopy could be instrumental in training the next generation of endoscopic surgeons. Further research is required in a clinical setting.

LEVEL OF EVIDENCE

2b Laryngoscope, 129:1280-1285, 2019.

Giant pituitary adenoma: histological types, clinical features and therapeutic approaches

Giant pituitary adenomas comprise about 6-10% of all pituitary tumors. They are mostly clinically non-functioning adenomas and occur predominantly in males. The presenting symptoms are usually secondary to compression of neighboring structures, but also due to partial or total hypopituitarism. Functioning adenomas give rise to specific symptoms of hormonal hypersecretion. The use of dopamine agonists is considered a first-line treatment in patients with giant macroprolactinomas. Somatostatin analogs can also be used as primary treatment in cases of growth hormone and thyrotropin producing giant adenomas, although remission of the disease is not achieved in the vast majority of these patients. Neurosurgical treatment, either through transsphenoidal or transcranial surgery, continues to be the treatment of choice in the majority of patients with giant pituitary adenomas. The intrinsic complexity of these tumors requires the use of different therapies in a combined or sequential way. A multimodal approach and a therapeutic strategy involving a multidisciplinary team of expert professionals form the basis of the therapeutic success in these patients.

Long-Term Endocrine Outcomes Following Endoscopic Endonasal Transsphenoidal Surgery for Acromegaly and Associated Prognostic Factors

BACKGROUND

Long-term remission rates from endoscopic transsphenoidal surgery for acromegaly and their relationship to prognostic indicators of disease aggressiveness are not well documented.

OBJECTIVE

To investigate long-term remission rates in patients with acromegaly after endoscopic transsphenoidal surgery, and correlate this with molecular and radiographic markers of disease aggressiveness.

METHODS

We identified all patients undergoing endoscopic transsphenoidal surgery for acromegaly from 2005 to 2013 at Cedars-Sinai Pituitary Center. Hormonal remission was established by normal insulin-like growth factor (IGF)-1, basal serum growth hormone <2.5 ng/mL, and growth hormone suppression to <1 ng/mL following oral glucose tolerance test. Oral glucose tolerance test was performed at 3 months after surgery, and then as indicated. IGF-1 was measured at 3 months and then at least annually. We evaluated tumor granularity, nuclear expression of p21, Ki67 index, and extent of cavernous sinus invasion, and correlated these with remission status.

RESULTS

Fifty-eight patients that underwent surgery had follow-up from 38 to 98 months (mean 64 ± 32.2 months). There were 21 microadenomas and 37 macroadenomas. Three months after surgery 40 of 58 patients (69%) were in biochemical remission. Four additional patients were in remission at 6 months after surgery, and 1 patient had recurrence within the first year after surgery. At last follow-up, 43 of 44 (74.1%) of patients remained in remission. Cavernous sinus invasion by tumor predicted failure to achieve remission.

CONCLUSIONS

Prognostic markers of disease aggressiveness other than cavernous sinus invasion did not correlate with surgical outcome. Long-term remission after surgery alone was achieved in 74% of patients, indicating long-term efficacy of endoscopic surgery.

The posterior nasoseptal flap: A novel technique for closure after endoscopic transsphenoidal resection of pituitary adenomas

Background:

While effective for the repair of large skull base defects, the Hadad-Bassagasteguy nasoseptal flap increases operative time and can result in a several-week period of postoperative crusting during re-mucosalization of the denuded nasal septum. Endoscopic transsphenoidal surgery for pituitary adenoma resection is generally not associated with large dural defects and high-flow cerebrospinal fluid (CSF) leaks requiring extensive reconstruction. Here, we present the posterior nasoseptal flap as a novel technique for closure of skull defects following endoscopic resection of pituitary adenomas. This flap is raised in all surgeries during the transnasal exposure using septal mucoperiosteum that would otherwise be discarded during the posterior septectomy performed in binostril approaches.

Methods:

We present a retrospective, consecutive case series of 43 patients undergoing endoscopic transsphenoidal resection of a pituitary adenoma followed by posterior nasoseptal flap placement and closure. Main outcome measures were extent of resection and postoperative CSF leak.

Results:

The mean extent of resection was 97.16 ± 1.03%. Radiographic measurement showed flap length to be adequate. While a defect in the diaphragma sellae and CSF leak were identified in 21 patients during surgery, postoperative CSF leak occurred in only one patient.

Conclusions:

The posterior nasoseptal flap provides adequate coverage of the surgical defect and is nearly always successful in preventing postoperative CSF leak following endoscopic transsphenoidal resection of pituitary adenomas. The flap is raised from mucoperiosteum lining the posterior nasal septum, which is otherwise resected during posterior septectomy. Because the anterior septal cartilage is not denuded, raising such flaps avoids the postoperative morbidity associated with the larger Hadad-Bassagasteguy nasoseptal flap.

Evolution of Technique in Endoscopic Transsphenoidal Surgery for Pituitary Adenoma: A Single Institution Experience from 220 Procedures

Introduction Endoscopic transsphenoidal surgery (ETSS) for pituitary adenoma (PA) has been a recent shift from the traditional microscopic technique. Although some literature demonstrated superiority of ETSS over the microscopic method and some evaluated mono- vs. binostril access within the ETSS, none had explored the potential influence of dedicated instrument, as this procedure had evolved, on patients' outcomes when compared to traditional microscopic tools. Objective To investigate our own clinical and radiographic outcomes of ETSS for PA with its technical evolution over time as well as a significance of, having vs. lacking, the special endoscopic tools. Methods Included patients underwent ETSS for PA performed by the first author (AH). Prospectively recorded patients' data concerning pre-, intra- and postoperative clinical and radiographic assessments were subject to analysis. The three groups of differently evolving ETSS techniques, beginning with mononostril (MN) to binostril ETSS with standard microsurgical instruments (BN1) and, lastly, binostril ETSS with specially-designed endoscopic tools (BN2), were examined for their impact on the intra- and, short- and long-term, postoperative results. Also, the survival after ETSS for PA, as defined by the need for reintervention in each technical group, was appraised. Results From January 2006 to 2012, there were 47, 101 and 72 ETSS, from 183 patients, in the MN, BN1 and BN2 cohorts, respectively. Significant preoperative findings were greater proportion of patients with prior surgery (p=0.01) and tumors with parasellar extension (p=0.02) in the binostril (BN1&2) than the MN group. Substantially shorter operative time and less amount of blood loss were evident as our technique had evolved (p<0.001). Despite higher incidence, and more advanced grades, of cerebrospinal fluid leakage in the binostril groups (p < 0.001), the requirement for post-ETSS surgical repair was less than the mononostril cohort (p=0.04). At six-month follow-up (n=214), quantitative radiographic outcome analysis was markedly superior in BN2. Consequently, long-term result was better in this latest technical group. Important negative risk factors, from multivariate Cox regression analysis, were prior surgery, Knosp grade, and firm tumor while BN1, BN2 and percentages of anteroposterior dimension PA removal had positive effect on longer survival. Conclusion The evolution of technique for ETSS for PA from MN to BN2 has shown its efficacy by improving intra- and postoperative outcomes in our study cohorts. Based on our results, not only that a neurosurgeon, wishing to start performing ETSS, should enroll in a formal fellowship training but he/she should also utilize advanced endoscopic tools, as we have proved its superior results in dealing with PA.

Endoscopic Endonasal Surgery for Treatment of Pituitary Apoplexy: 16 Years of Experience in a Specialized Pituitary Center

OBJECTIVE

Symptomatic pituitary apoplexy is a rare but life-threatening condition caused by sudden hemorrhage or infarction of a pituitary adenoma. In the current study, we aim to evaluate the clinical presentation, management, and clinical outcomes in a cohort of patients who were treated for this condition in our center in the last 16 years.

METHODS

We performed a retrospective analysis of all patients who underwent endoscopic endonasal surgery for treatment of symptomatic pituitary apoplexy between 2001 and 2016 in our center.

RESULTS

A total of 39 patients were included in the study, mean age of 54.9 years (range, 18-70 years) and mean follow-up 5.1 years (range, 0.6-16 years). Most of the patients had nonfunctioning adenomas (32 patients). Headache (89%), visual impairment (79%), and hypopituitarism (86%) were the most common preoperative findings. Surgical treatment led to gross total resection in 31 patients (79.4%). During follow-up, visual fields and oculomotor improvement was observed in 23 (74.1%) and 21 (67.7%) of the patients, respectively. Intractable headache also improved in all patients. Hypopituitarism was present in 77% of patients after surgery. In this series, no cerebrospinal fluid leak, vascular injury, or infection was observed. There was no postoperative mortality.

CONCLUSIONS

The endoscopic endonasal transsphenoidal approach is an effective modality to treat pituitary apoplexy with a high rate of success and minimal risk in selected cases. Although reversion of preoperative visual deficits is often observed, hormonal deficits tend to persist, and require long-term hormonal therapy, even after successful endoscopic endonasal surgical resection.

Endoscopic Endonasal Surgery for Tumors of the Cavernous Sinus: A Series of 234 Patients

BACKGROUND

Cavernous sinus (CS) tumors often are considered inoperable. We present our experience with endoscopic endonasal surgery (EES) and compare the outcomes for different tumor.

METHODS

EES (medial or lateral approach) was used in 234 patients with CS tumors. The cohort included 175 (75%) pituitary adenomas and 59 (25%) nonadenomatous lesions.

RESULTS

Presenting symptoms were significantly different between the 2 groups, with cranial neuropathies occurring mainly in nonadenomas (P < 0.0001). The overall gross total tumor resection rate from the CS was 37.3% (37.1% in adenomas, 38.1% in non-adenomas). In total, preexisting cranial nerve (CN) dysfunction improved in 56.4% of the patients. After treatment completion (including radiation of residual tumor), 83.3% of acromegalic patients, 50% of prolactinomas and 33.3% of Cushing's disease, were in remission. Visual loss improved in 86.8% of adenomas and in 70.8% of nonadenomas. Intracavernous CN palsies improved in 77.3% of adenomas and 42.4% of nonadenomas. New permanent CN palsies occurred in 7 nonadenomas, which is significantly greater than in adenomas (P = 0.007). The leak rate of cerebrospinal fluid was 6.3% for adenomas and 11.9% for nonadenomas. Four patients suffered an internal carotid artery injury with no neurologic sequelae in 3 cases and 1 death (0.4%).

CONCLUSIONS

EES provides an easily accessible midline corridor to the CS with equivalent or superior results to transcranial approaches in the management of select tumors. Symptomatology due to CS invasion is more likely to improve in pituitary adenomas and the rate of surgical complications is greater in nonadenomas. Using a team approach, the overall mortality due to vascular injury is low.

The Value of Intraoperative Magnetic Resonance Imaging in Endoscopic and Microsurgical Transsphenoidal Pituitary Adenoma Resection

BACKGROUND

The routine use of intraoperative magnetic resonance imaging (iMRI) helps to achieve gross total resection in transsphenoidal pituitary surgery. We compared the added value of iMRI for extent of resection in endoscopic versus microsurgical transsphenoidal adenomectomy.

METHODS

A total of 96 patients with pituitary adenoma were included. Twenty-eight consecutive patients underwent endoscopic transsphenoidal tumor resection. For comparison, we used a historic cohort of 68 consecutive patients treated microsurgically. We evaluated the additional resection after conducting iMRI using intraoperative and late postoperative volumetric tumor analysis 3 months after surgery. Demographic data, clinical symptoms, and complications as well as pituitary function were evaluated.

RESULTS

We found significantly fewer additional resections after conducting iMRI in the endoscopic group (P = 0.042). The difference was even more profound in Knosp grade 0-2 adenomas (P = 0.029). There was no significant difference in Knosp grade 3-4 adenomas (P = 0.520). The endoscopic approach was associated with smaller intraoperative tumor volume (P = 0.023). No significant difference was found between both techniques in postoperative tumor volume (P = 0.228). Satisfactory results of pituitary function were significantly more often associated with an endoscopic approach in the multiple regression analysis (P = 0.007; odds ratio, 17.614; confidence interval 95%, 2.164-143.396).

CONCLUSIONS

With the endoscopic approach, significantly more tumor volume reduction was achieved before conducting iMRI, decreasing the need for further resection. This finding was even more pronounced in adenomas graded Knosp 0-2. In the case of extensive and invasive adenomas with infiltration of cavernous sinus and suprasellar or parasellar extension, additional tumor resection and increase in the extent of resection was achieved with iMRI in both groups. The endoscopic approach seems to result in better endocrine outcomes, especially in Knosp grade 0-2 pituitary adenomas.

Efficacy of Microsurgical Sublabial Approach (MSA) Versus Endoscopic Endonasal Approach (EEA) for the Treatment of Pituitary Adenomas Based on Radiological and Hormonal Outcome

BACKGROUND

The purpose of this study was to compare the surgical efficacy of the microsurgical sublabial approach (MSA) versus the endoscopic endonasal approach (EEA) for the treatment of pituitary adenomas, based on short-term (12 months) radiological and endocrinological follow-up.

METHODS

One hundred and fourteen patients affected by pituitary adenoma were enrolled at our Unit between January 2007 and February 2012; 72 were treated with MSA, and 42 with EEA. The preoperative parameters considered were: type of lesion (secreting or nonsecreting), lesion size, presence of intralesional hemorrhage, lesion perimeter (nodular vs. uniform), intrasellar vs. suprasellar, involvement of cavernous sinus, and osteodural infiltration. Hormonal assays and magnetic resonance imaging (MRI) scans were performed at 12 months after the surgical procedure.

RESULTS

Univariate analysis of the data documented a statistically significant difference in favor of MSA for the subgroups of secreting adenomas (90.9 % vs. nonsecreting 48.3 %), microadenomas (100 % vs. macroadenomas 57.1 %), adenomas without osteodural infiltration (87.5 % vs. 55.5 % with the infiltration) or those without intralesional hemorrhage (75 % vs. 45.9 % with the hemorrhage), and growth hormone (GH) adenomas (88.8 % vs. 43.7 %). Multivariate analysis confirmed the greater effectiveness of MSA for the treatment of micro-secreting adenomas.

CONCLUSIONS

Recent advances in the EEA for treating pituitary adenomas could lead to this modality replacing the microsurgical technique. In our experience the MSA allowed us to achieve better results in the treatment of microadenomas.

Neuroendoscopy - Is it safe?

BACKGROUND

The effect of heat in endoscopic instruments used for laparoscopy and hysteroscopy has been well-studied. Reports of thermal injury from nasal endoscopes have also been reported. However, there are no experimental studies, which have objectively documented and provided recommendations for safe use of endoscopes in neurosurgery.

OBJECTIVES

To study the heat generated at the tip of the endoscope and the subsequent thermal damage caused to a cotton drape placed in proximity, by varying the intensity of light delivered through different optical cables, ambient (operating room) temperatures and working distances.

MATERIALS AND METHODS

The study was carried out in the operation theater using a 300 watt xenon light source connected to the endoscope with 3.5 mm and 4.8 mm optical cables. A digital thermometer was used to record the heat generated at the tip of the endoscope.

RESULTS

The heat generated at the tip of the endoscope reached its peak in the first 6 min and attained a plateau at 15 min after turning on a light source of 60% intensity. Thermal injury to the cotton drape took a longer time with a 3.8 mm cable compared with 4.8 mm cable. The heat generated at the tip of the endoscope, and thereby the thermal injury caused was found to be lower when the ambient temperature was close to 20°C.

CONCLUSIONS

Complications related to thermal injuries caused by heat generated at the tip of an endoscope can be reduced by using a smaller diameter cable, light intensity of 60%, increasing the working distance (as permissible), reducing the time spent for dissection while keeping the endoscope very close to the target and lowering the ambient temperature to 20°C.

Pediatric pituitary resection: characterizing surgical approaches and complications

BACKGROUND

Although there has been extensive study evaluating adult pituitary surgery, there has been scant analysis among children. Our objective was to evaluate a population-based resource to characterize nationwide trends in surgical approach, hospital stay, and complications among children undergoing pituitary surgery.

METHODS

The Kids' Inpatient-Database (KID) files (2009/2012) were evaluated for pituitary gland excisions. Procedure, patient demographics, length of inpatient stay, inpatient costs, hospital setting, and surgical complications were analyzed.

RESULTS

A weighted incidence of 1071 cases were analyzed; the majority (77.6%) underwent transsphenoidal resections. These patients had significantly decreased hospital costs and lengths of stay. Patients undergoing transfrontal approaches had significantly greater rates of postoperative diabetes insipidus (DI) (66.5%), panhypopituitarism (38.8%), hydrocephalus, and visual deficits. Among transsphenoidal patients, males had greater rates of postoperative hydrocephalus (5.5%) and panhypopituitarism (17.5%) than females, and patients ≤10 years old had greater rates of these 2 complications (14.5%, 19.4%, respectively) as well as DI (61.3%).

CONCLUSION

A greater proportion of children undergo transfrontal approaches for pituitary lesions than in their adult counterparts. This difference may harbor a potential to influence future sellar resection approaches in children toward a transsphenoidal operation when surgically feasible. Patients undergoing transfrontal procedures have greater risks for many intraoperative and postoperative complications relative to individuals undergoing transsphenoidal resections. Among patients undergoing transsphenoidal approaches, males had significantly greater rates of postoperative hydrocephalus and panhypopituitarism, and younger children had greater rates of postoperative DI, hydrocephalus, and panhypopituitarism. These data reinforce the need for greater vigilance in the postoperative care of younger children undergoing transsphenoidal surgery.

Pituitary adenomas: historical perspective, surgical management and future directions

Pituitary adenomas are among the most common central nervous system tumors. They represent a diverse group of neoplasms that may or may not secrete hormones based on their cell of origin. Epidemiologic studies have documented the incidence of pituitary adenomas within the general population to be as high as 16.7%. A growing body of work has helped to elucidate the pathogenesis of these tumors. Each subtype has been shown to demonstrate unique cellular changes potentially leading to tumorigenesis. Surgical advancements over several decades have included microsurgery and the employment of the endoscope for surgical resection. These advancements increase the likelihood of gross-total resection and have resulted in decreased patient morbidity.

Multi-institutional study of risk factors for perioperative morbidity following transnasal endoscopic pituitary adenoma surgery

BACKGROUND

The goal of this study was to identify preoperative risk factors associated with increased perioperative morbidity after endoscopic pituitary surgery.

METHODS

A retrospective review of patients undergoing endoscopic pituitary adenoma surgery between 2002 and 2014 at 6 international centers was performed. Standard demographic and comorbidity data, as well as information regarding tumor extent and treatment were collected. Logistic regression was used to examine risk factors for the following 30-day outcomes: systemic complications, intracranial complications, postoperative cerebrospinal fluid (CSF) leaks, length of hospital stay, readmission, and reoperation.

RESULTS

Data was collected on 982 patients with a mean age of 52 years. The median body mass index (BMI) for all patients was 30.9 kg/m(2) with 56% female. The median hospital stay was 5 days and 23.8% of patients suffered a postoperative adverse event. Systemic complications occurred in 3.2% of patients and intraventricular extension was a risk factor (odds ratio [OR] 8.9). Intracranial complications occurred in 7.3% of patients and risk factors included previous radiation (OR 8.6) and intraventricular extension (OR 7.9). Reoperation occurred in 6.5% of patients and intraventricular extension (OR 7.3) and age (<40 years, OR 3.5; 40 to 64 years, OR 3.2) were risk factors. Postoperative CSF leaks occurred in 5.5% of patients and risk factors included female gender (OR 2.4), BMI ≥ 30 (OR 2.1), age (<40 years, OR 5.3; 40 to 64 years, OR, 7.9), and intraventricular extension (OR, 9.5).

CONCLUSION

Postoperative endoscopic pituitary adenoma surgery complications are associated with tumors with intraventricular extension, preoperative radiation, as well as common patient comorbidities. Identification of these factors may permit implementation of strategies to reduce postoperative complications.

[Advances in the surgical treatment of tumors of the pituitary region : rhino-neurosurgical transnasal endoscopic surgery]

Conventional microscopic surgery of pituitary adenomas offers excellent results with regard to local tumour control and endocrine function. Overall patient morbidity and mortality is low. However, recent studies demonstrate further improvements in tumour resection control and more favourable endocrine/ophthalmologic results when endoscopic techniques are applied, as well as an overall reduction in peri-interventional morbidity. Additionally, use of endoscopic techniques in rhino-neurosurgical cooperation achieved better specifically rhinologic results and improved subjective comfort for patients. The cooperative rhino-neurosurgical approach not only allows for optimal treatment of the primary pituitary pathology, but also treatment of additional nasal and paranasal pathologies, such as a deviated septum or disturbed drainage of the paranasal sinus.

Clinical application of anatomy landmarks for microscopic endonasal transsphenoidal surgery for pituitary adenomas

It is important to identify relevant anatomical landmarks on the route of endonasal transsphenoidal surgery (TSS) for pituitary adenomas to improve the gross total resection and the remission of disease. We therefore retrospectively studied the clinical outcomes of 148 patients who underwent single nostril endonasal TSS for pituitary adenomas. The anatomic basis of these procedures was evaluated. The important landmarks included the mucosal sphenoid ostia, the sphenoid keel, the osseous ostia and the nutrient arteries nearby, the sellar bulge, and the carotid protuberance, which outlined a clear route to the sella turcica with the best view and less tissue damage. Based on these landmarks, 148 cases of endonasal TSS were successfully performed to achieve 70.3% of gross total resection and remission, respectively. The complications were controlled to the least. Therefore, the application of these landmarks will help to prevent complications and improve the long-term outcomes.

Endoscopic endonasal approach for growth hormone secreting pituitary adenomas: outcomes in 53 patients using 2010 consensus criteria for remission

We report the outcomes of the endoscopic endonasal approach (EEA) for resection of growth hormone secreting pituitary adenomas using 2010 consensus criteria. We also assess outcomes with additional medical therapy and radiosurgery (RS) for patients not achieving remission with EEA alone. A retrospective review of 53 patients who had follow up endocrinologic data at least 3 months post-surgery was performed among patients who were treated by EEA between 1998 and 2012. Data were analyzed for remission using GH and IGF-I levels based on 2010 consensus criteria. We also analyzed the outcomes using 2000 consensus criteria for ease in comparison to prior studies of outcomes of surgery for acromegaly. In this series of mostly large (88.2% macroadenomas), invasive (46.9% Hardy-Wilson C, D, E) adenomas, there were 27 patients (50.9%) who achieved remission after EEA only. For patients who had no remission with EEA alone, RS and/or medical therapy were used and 37 patients (69.8 %) achieved remission overall. Statistical analysis showed larger tumor size, Hardy Stages C, D, E and Knosp Scores 3, 4 to be predictive against remission for EEA only and EEA with other modalities. The volume of residual tumor after EEA was not found to be predictive of remission with additional therapies. We used stringent consensus criteria from 2010 in a series which included a high proportion of invasive GH secreting adenomas to show that EEA alone or combined with other modalities results in comparable remission rates to earlier studies which used less strict criteria, while retaining low complication rates.

Field of view comparison between two-dimensional and three-dimensional endoscopy

OBJECTIVES/HYPOTHESIS

Relative to microscopic transnasal surgery, endoscopic surgery provides improved visualization with an increased field of view. Advances such as high-definition (HD) and three-dimensional (3D) endoscopy have been introduced and clearly improve visualization. However, do both technologies maintain an increased field of view? We hypothesize that the field of view of 3D endoscopy is restricted relative to two-dimensional (2D) HD endoscopy.

STUDY DESIGN

Laboratory investigation, prospective case series.

METHODS

Standard measurements at 6-cm and 2-cm working distances where made to determine the comparative field of view utilizing Storz 0° 2D HD and Visionsense 3D endoscopes. Relative measurements were then made to determine field of view. Five clinical patients were then utilized to confirm laboratory studies and demonstrate the relative field of view change.

RESULTS

3D endoscopy demonstrates a 52% loss of field of view compared to 2D endoscopy in a controlled lab testing. This was confirmed in a small clinical patient series where a 55% ± 3% relative field of view reduction was observed.

CONCLUSIONS

When working with 3D endoscopy in a currently available commercial product, the operator should be aware that relative to HD 2D endoscopy, there is a field of view restriction of 52%.

LEVEL OF EVIDENCE

N/A.

Incidence and significance of intraoperative cerebrospinal fluid leak in endoscopic pituitary surgery using intrathecal fluorescein

OBJECTIVE

The true rate of intraoperative cerebrospinal fluid (iCSF) leak during pituitary surgery is not well known because small iCSF leaks are easily missed. Our objective is to determine the rate and significance of iCSF leak in endoscopic pituitary surgery with intrathecal (IT) fluorescein administration and determine factors predictive of iCSF leak.

METHODS

IT fluorescein was administered in 203 consecutive endoscopic, endonasal pituitary surgeries. The rate of iCSF leak was noted prospectively and correlated with tumor diameter and volume, gross total resection, and the learning curve. Postoperative CSF leak rate, complications, and nasoseptal flap utility were also investigated.

RESULTS

The rate of iCSF leak was 61% overall, 44% for tumors<2 cm compared to 72% for tumors≥2 cm and 35% for tumors<1.5 cm3 compared to 68% for those≥1.5 cm3 (P<0.001). Postoperative CSF leak was significantly lower after the first 50 cases (0.7% vs. 10%; P<0.005) with overall leak of 3%. For tumors>2 cm, the introduction of nasoseptal flap reduced the rate of postoperative CSF leak from 5.6% to 1.4%. We did not find any complications clearly related with the use of IT fluorescein.

CONCLUSION

The rate of iCSF leak during endoscopic pituitary surgery using IT fluorescein is higher than previously reported. Tumor diameter and volume are best predictors of the risk of iCSF leak. Based on this knowledge and a closure algorithm that includes a lumbar drain and nasoseptal flap for larger tumors (>2.5 cm), we can conclude that the postoperative CSF leak rate remains exceptionally low, particularly once the learning curve is overcome.

Endoscopic, endonasal, trans-sphenoidal hypophysectomy: retrospective analysis of 171 procedures

INTRODUCTION

Endoscopic, transnasal management of pituitary gland neoplasms is a widely accepted alternative to the traditional microscopic approach. This study aimed to determine outcomes and complication rates for the largest UK series of endoscopic, trans-sphenoidal hypophysectomies reported to date.

METHODS

We performed a retrospective analysis of 136 primary resections and 35 revision cases performed at a tertiary referral centre.

RESULTS AND ANALYSIS

Total tumour resection was confirmed in over 85 per cent of primary and revision cases, with biochemical remission in 60 per cent. The incidence of complications such as epistaxis, sphenoid sinus problems, endocrine insufficiency, visual disturbance, post-operative haemorrhage, cranial nerve injury and mortality was significantly lower, compared with similar series using the microscopic approach.

CONCLUSION

Despite its steep 'learning curve', our series demonstrates that the endoscopic approach not only allows superior anatomical visualisation and therefore facilitates full oncological resection of tumours, but also reduces the incidence of peri-operative complications.