Role of Endoscopic Skull Base and Keyhole Surgery for Pituitary and Parasellar Tumors Impacting Vision

Supraorbital and mini-pterional keyhole craniotomies for brain tumors: a clinical and anatomical comparison of indications and outcomes in 204 cases

OBJECTIVE

The authors' objective was to compare the indications, outcomes, and anatomical limits of supraorbital (SO) and mini-pterional (MP) craniotomies in patients with intra- and extraaxial brain tumors, and to assess approach selection, utility of endoscopy, and surgical field overlap.

METHODS

A retrospective analysis was conducted of all brain tumor patients who underwent an SO or MP approach. The analyzed characteristics included pathology, endoscopy use, extent of resection, length of stay (LOS), and complications. On the basis of preoperative MRI data, tumor heatmaps were constructed to compare surgical access provided by both routes, including coronal projection heatmaps for parasellar tumors.

RESULTS

From 2007 to 2020, 158 patients underwent 173 (84.8%) SO craniotomies and 30 patients underwent 31 (15.2%) MP craniotomies; 71 (34.8%) procedures were reoperations. Of these 204 operations, 110 (63.6%) SO and 21 (67.7%) MP approaches were for extraaxial tumors (meningiomas in 65% and 76.2%, respectively). Gliomas and metastases together represented 84.1% and 70% of intraaxial tumors accessed with SO and MP approaches, respectively. Overall, 56.1% of tumors accessed with the SO approach and 41.9% of those accessed with the MP approach were in the parasellar region. Axial projection heatmaps showed that SO access extended along the entire ipsilateral and medial contralateral anterior cranial fossa, parasellar region, ipsilateral sylvian fissure, medial middle cranial fossa, and anterior midbrain, whereas MP access was limited to the ipsilateral middle cranial fossa, sylvian fissure, lateral parasellar region, and posterior aspect of anterior cranial fossa. Coronal projection heatmaps showed that parasellar access extended further superiorly with the SO approach compared with that of the MP approach. Endoscopy was utilized in 98 (56.6%) SO craniotomies and 7 (22.6%) MP craniotomies, with further tumor resection in 48 (49%) and 5 (71.4%) cases, respectively. Endoscope-assisted tumor removal was clustered in areas that were generally at farther distances from the craniotomy or in angled locations such as the cribriform plate region where microscopic visualization is limited. Gross-total or near-total resection was achieved in 120/173 (69%) SO approaches and 21/31 (68%) MP approaches. Major complications occurred in 11 (6.4%) SO approaches and 1 (3.2%) MP approach (p = 0.49). The median LOS decreased to 2 days in the last 2 years of the study.

CONCLUSIONS

This clinical experience suggests the SO and MP craniotomies are versatile, safe, and complementary approaches for tumors located in the anterior and middle cranial fossae and perisylvian and parasellar regions. The SO route, used in 85% of cases, achieved greater overall reach than the MP route. Both approaches may benefit from expanded visualization with endoscopy.

Minimally invasive surgical treatment of intracranial meningiomas in elderly patients (≥ 65 years): outcomes, readmissions, and tumor control

OBJECTIVE

Increased lifespan has led to more elderly patients being diagnosed with meningiomas. In this study, the authors sought to analyze and compare patients ≥ 65 years old with those < 65 years old who underwent minimally invasive surgery for meningioma. To address surgical selection criteria, the authors also assessed a cohort of patients managed without surgery.

METHODS

In a retrospective analysis, consecutive patients with meningiomas who underwent minimally invasive (endonasal, supraorbital, minipterional, transfalcine, or retromastoid) and conventional surgical treatment approaches during the period from 2008 to 2019 were dichotomized into those ≥ 65 and those < 65 years old to compare resection rates, endoscopy use, complications, and length of hospital stay (LOS). A comparator meningioma cohort of patients ≥ 65 years old who were observed without surgery during the period from 2015 to 2019 was also analyzed.

RESULTS

Of 291 patients (median age 60 years, 71.5% females, mean follow-up 36 months) undergoing meningioma resection, 118 (40.5%) were aged ≥ 65 years and underwent 126 surgeries, including 20% redo operations, as follows: age 65-69 years, 46 operations; 70-74 years, 40 operations; 75-79 years, 17 operations; and ≥ 80 years, 23 operations. During 2015-2019, of 98 patients referred for meningioma, 67 (68%) had surgery, 1 (1%) had radiosurgery, and 31 (32%) were observed. In the 11-year surgical cohort, comparing 173 patients < 65 years versus 118 patients ≥ 65 years old, there were no significant differences in tumor location, size, or outcomes. Of 126 cases of surgery in 118 elderly patients, the approach was a minimally invasive approach to skull base meningioma (SBM) in 64 cases (51%) as follows: endonasal 18, supraorbital 28, minipterional 6, and retrosigmoid 12. Endoscope-assisted surgery was performed in 59.5% of patients. A conventional approach to SBM was performed in 15 cases (12%) (endoscope-assisted 13.3%), and convexity craniotomy for non-skull base meningioma (NSBM) in 47 cases (37%) (endoscope-assisted 17%). In these three cohorts (minimally invasive SBM, conventional SBM, and NSBM), the gross-total/near-total resection rates were 59.5%, 60%, and 91.5%, respectively, and an improved or stable Karnofsky Performance Status score occurred in 88.6%, 86.7%, and 87.2% of cases, respectively. For these 118 elderly patients, the median LOS was 3 days, and major complications occurred in 10 patients (8%) as follows: stroke 4%, vision decline 3%, systemic complications 0.7%, and wound infection or death 0. Eighty-three percent of patients were discharged home, and readmissions occurred in 5 patients (4%). Meningioma recurrence occurred in 4 patients (3%) and progression in 11 (9%). Multivariate regression analysis showed no significance of American Society of Anesthesiologists physical status score, comorbidities, or age subgroups on outcomes; patients aged ≥ 80 years showed a trend of longer hospitalization.

CONCLUSIONS

This analysis suggests that elderly patients with meningiomas, when carefully selected, generally have excellent surgical outcomes and tumor control. When applied appropriately, use of minimally invasive approaches and endoscopy may be helpful in achieving maximal safe resection, reducing complications, and promoting short hospitalizations. Notably, one-third of our elderly meningioma patients referred for possible surgery from 2015 to 2019 were managed nonoperatively.

Endoscopic Endonasal and Supraorbital Removal of Tuberculum Sellae Meningiomas: Anatomic Guides and Operative Nuances for Keyhole Approach Selection

BACKGROUND

With growing worldwide endoscopy experience, endonasal and supraorbital removal of tuberculum sellae meningiomas (TSM) has increased.

OBJECTIVE

To describe anatomic factors for guiding approach selection and outcomes.

METHODS

Retrospective analysis of patients undergoing endonasal or supraorbital TSM resection: approach criteria, clinical outcomes, acute magnetic resonance imaging (MRI) fluid-attenuated inversion-recovery (FLAIR)/T2 changes.

RESULTS

From 2008 to 2020, 33 patients (mean age 55 ± 11 yr) were identified: 20 (61%) had endonasal and 13 (39%) supraorbital removal. Comparing endonasal and supraorbital approaches, mean tumor volume (3.7 ± 3.5 cm3 vs 7.7 ± 8.5 cm3, P = .07); percent tumor above planum (42% vs 65%, P = .02), and lateral tumor beyond supraclinoid internal carotid arteries (1.4 ± 2.0 mm vs 4.0 ± 3.2 mm, P = .006) were greater for supraorbital route. Sellar depth was greater for endonasal route tumors (12.2 ± 2.6 mm vs 9.3 ± 2.4 mm, P = .003). Endoscopy, used in 10/13(77%) supraorbital cases, was helpful in additional tumor removal in 4/10(40%). Gross total removal and mean volumetric tumor resection were 16/20(80%) and 97.5% by endonasal, and 5/13(39%) and 96% by supraorbital route. Vision improved in 12/17 (71%) endonasal, 6/8 (75%) supraorbital operations, and worsened in 1 (3%) supraorbital case. Endonasal approach with optic canal decompression increased over study period: 15/20 (75%) endonasal patients vs 1/13(8%) supraorbital (P < .001). Postoperative FLAIR/T2 MRI changes occurred in 2/12 supraorbital and 0/20 endonasal cases.

CONCLUSION

In our experience, both endonasal and supraorbital routes are safe and effective for TSM removal. Greater tumor extension below planum and medial optic canal invasion favor endonasal route, while larger size and lateral extension favor supraorbital route. Given high frequency of TSM growth into optic canals and better access for medial optic canal tumor removal, endonasal route may be preferred for most TSMs.

Streamlining brain tumor surgery care during the COVID-19 pandemic: A case-control study

BACKGROUND

The COVID-19 pandemic forced a reconsideration of surgical patient management in the setting of scarce resources and risk of viral transmission. Herein we assess the impact of implementing a protocol of more rigorous patient education, recovery room assessment for non-ICU admission, earlier mobilization and post-discharge communication for patients undergoing brain tumor surgery.

METHODS

A case-control retrospective review was undertaken at a community hospital with a dedicated neurosurgery and otolaryngology team using minimally invasive surgical techniques, total intravenous anesthesia (TIVA) and early post-operative imaging protocols. All patients undergoing craniotomy or endoscopic endonasal removal of a brain, skull base or pituitary tumor were included during two non-overlapping periods: March 2019-January 2020 (pre-pandemic epoch) versus March 2020-January 2021 (pandemic epoch with streamlined care protocol implemented). Data collection included demographics, preoperative American Society of Anesthesiologists (ASA) status, tumor pathology, and tumor resection and remission rates. Primary outcomes were ICU utilization and hospital length of stay (LOS). Secondary outcomes were complications, readmissions and reoperations.

FINDINGS

Of 295 patients, 163 patients were treated pre-pandemic (58% women, mean age 53.2±16 years) and 132 were treated during the pandemic (52% women, mean age 52.3±17 years). From pre-pandemic to pandemic, ICU utilization decreased from 92(54%) to 43(29%) of operations (p<0.001) and hospital LOS≤1 day increased from 21(12.2%) to 60(41.4%), p<0.001, respectively. For craniotomy cohort, median LOS was 2 days for both epochs; median ICU LOS decreased from 1 to 0 days (p<0.001), ICU use decreased from 73(80%) to 29(33%),(p<0.001). For endonasal cohort, median LOS decreased from 2 to 1 days; median ICU LOS was 0 days for both epochs; (p<0.001). There were no differences pre-pandemic versus pandemic in ASA scores, resection/remission rates, readmissions or reoperations.

CONCLUSION

This experience suggests the COVID-19 pandemic provided an opportunity for implementing a brain tumor care protocol to facilitate safely decreasing ICU utilization and accelerating discharge home without an increase in complications, readmission or reoperations. More rigorous patient education, recovery room assessment for non-ICU admission, earlier mobilization and post-discharge communication, layered upon a foundation of minimally invasive surgery, TIVA anesthesia and early post-operative imaging are possible contributors to these favorable trends.

Pituitary adenomas in older adults (≥ 65 years): 90-day outcomes and readmissions: a 10-year endoscopic endonasal surgical experience

INTRODUCTION

Longer lifespan and newer imaging protocols have led to more older adults being diagnosed with pituitary adenomas. Herein, we describe outcomes of patients ≥ 65 years undergoing endoscopic adenoma removal. To address selection criteria, we also assess a conservatively managed cohort.

METHODS

A retrospective analysis of 90-day outcomes of patients undergoing endoscopic pituitary adenomectomy from 2010 to 2019 by a neurosurgical/ENT team was performed. Tumor subtype, cavernous sinus invasion, extent of resection/early remission, endocrinology outcomes, complications, re-operations and readmissions were analyzed. A comparator cohort ≥ 65 years undergoing clinical surveillance without surgery was also analyzed.

RESULTS

Of 468 patients operated on for pituitary adenoma, 123 (26%) were ≥ 65 years (range 65-93 years); 106 (86.2%) had endocrine-inactive adenomas; 18 (14.6%) had prior surgery. Of 106 patients with endocrine-inactive adenomas, GTR was achieved in 70/106 (66%). Of 17 patients with endocrine-active adenomas, early biochemical remission was: Cushing's 6/8; acromegaly 1/4; prolactinomas 1/5. Gland function recovery occurred in 28/58 (48.3%) patients with various degrees of preoperative hypopituitarism. New anterior hypopituitarism occurred in 3/110 (2.4%) patients; permanent DI in none. Major complications in 123 patients were: CSF leak 2 (1.6%), meningitis 1 (0.8%), vision decline 1 (0.8%). There were no vascular injuries, operative hematomas, anosmia, deaths, MIs, or thromboembolic events. Median length of stay was 2 days. Readmissions occurred in 14/123 (11.3%) patients, 57% for delayed hyponatremia. Intra-cohort analysis by age (65-69, 70-74, 75-79,  ≥ 80 years) revealed no outcome differences. Cavernous sinus invasion (OR 7.7, CI 1.37-44.8; p = 0.02) and redo-surgery (OR 8.5, CI 1.7-42.8; p = 0.009) were negative predictors for GTR/NTR. Of 105 patients evaluated for presumed pituitary adenoma beginning in 2015, 72 (69%) underwent surgery, 8 (7%) had prolactinomas treated with cabergoline and 25 (24%) continue clinical surveillance without surgery, including two on new hormone replacement.

CONCLUSION

This study suggests that elderly patients carefully selected for endoscopic adenoma removal can have excellent short-term outcomes including high resection rates, low complication rates and short length of stay. Our experience supports a multidisciplinary approach and the concept of pituitary centers of excellence. Based on our observations, approximately 25% of elderly patients with pituitary adenomas referred for possible surgery can be monitored closely without surgery.

Tuberculum Sellae Meningiomas in Pregnancy: 3 Cases Treated in the Second Trimester and Literature Review

BACKGROUND

Tuberculum sella meningiomas typically present with progressive visual loss. It is also known that meningiomas can become symptomatic during pregnancy. Herein we report on 3 patients who presented with progressive visual decline during pregnancy, prompting urgent surgical removal of their meningiomas.

CASE DESCRIPTIONS

From our prospectively collected brain tumor database, all women surgically treated for tuberculum sella meningioma since 2006 were retrospectively reviewed. Clinical presentation, surgical approach, perioperative management, and pathology of pregnant patients were reviewed and compared with those of the nonpregnant cohort. Of 43 women with newly diagnosed tuberculum sella meningioma, 3 (7%) presented in pregnancy with progressive visual loss, 1 in the late first trimester and 2 in the early second trimester. One woman pregnant with twins had a broad-based meningioma and underwent a supraorbital craniotomy and gross total tumor removal in her second trimester. Two women with singleton pregnancies both underwent endoscopic endonasal gross total tumor removal during their second trimesters. All 3 patients had visual recovery, 2 of which were complete, and all went on to have successful uncomplicated deliveries of their children and maintain normal pituitary gland function.

CONCLUSIONS

Presentation of tuberculum sella meningioma during pregnancy is uncommon but not rare, accounting for 7% of women in our series. Ideally, surgery is performed in the second trimester, ensuring fetal safety while restoring maternal vision and maintaining pituitary gland function are essential. Depending on tumor size and sellar anatomy, endoscopic endonasal or supraorbital keyhole craniotomy approaches are both viable options.

The Supraorbital Eyebrow Craniotomy for Intra- and Extra-Axial Brain Tumors: A Single-Center Series and Technique Modification

BACKGROUND

The supraorbital (SO) eyebrow craniotomy provides minimally invasive access to the anterior and middle fossae and parasellar region.

OBJECTIVE

To present a series of patients treated with the SO approach to assess outcomes, the impact of endoscopy, and describe a modified pericranial flap aimed at reducing postoperative frontalis paresis and hypesthesia.

METHODS

A retrospective analysis was undertaken of our prospective database of patients who underwent SO craniotomy for tumor/cyst removal. Patients were evaluated based on pathology, utility of endoscopy, extent of resection, complications, and functional/esthetic recovery.

RESULTS

From 2007 to 2018, 129 operations were performed in 117 patients (54% women; mean age 60 ± 16.5 yr). The most common lesions were meningiomas (43%), gliomas (15%), and metastases (15%). Prior surgery and/or radiation had been performed in 37% and 26% of patients, respectively. Endoscopy was used in 76 (61%) operations and allowed more complete tumor removal in 38 (50%). For first-time operations, gross-total removal was achieved in 78%. Major complications included stroke (3%), cranial nerve deficit (3%), acute hematoma (1%), and cerebrospinal fluid leak (1%). The modified pericranial flap technique used in 18 recent patients resulted in a shorter duration of transient frontalis paresis and forehead hypesthesia with complete functional recovery in all 18.

CONCLUSION

The SO craniotomy is an effective keyhole approach for intra- and extra-axial tumors. Endoscopic assistance may allow additional tumor removal in almost 30% of the cases. The modified pericranial flap appears to accelerate functional recovery, although additional patients and follow-up are required to better assess this technique.

Work-related musculoskeletal disorders among endoscopic transsphenoidal surgeons: a systematic review of prevalence and ergonomic interventions

Endoscopic transsphenoidal surgery is a surgical technique introduced in the last 20 years for the treatment of skull base pathologies and, in particular, pituitary tumours. Although the prevalence of work-related musculoskeletal disorders is usually significantly higher in endoscopists and minimally invasive surgeons compared to other surgical and medical specialties, reviews on the prevalence of disorders among neurosurgeons dedicated to endoscopic transsphenoidal surgery are not available. This article performs a systematic review to identify the work-related musculoskeletal disorders among transsphenoidal neurosurgeons, their prevalence and the ergonomic interventions proposed to reduce risk factors and prevent disorders. The results show that the ergonomics of transsphenoidal neurosurgeons is an under-investigated topic. Indeed, specific prevalence data are not available. In addition, only a few papers suggest interventions and guidelines, but without objective assessment of the outcomes to confirm the ergonomic benefit. Based on these gaps in the literature, a future research agenda is proposed.

Supraorbital keyhole approach: Pure endoscopic and endoscope-assisted perspective

OBJECTIVE

To assess the assumed advantages of pure endoscopic and endoscope-assisted methods for the supraorbital keyhole approach. The aim is to demonstrate visibility and accessibility of the pure endoscope approach as a possible standard approach for the supraorbital keyhole approach.

PATIENTS AND METHODS

We performed eight dissections on four cadaver heads using an operating microscope, an endoscope, and neuronavigation. The visibility and accessibility of the anterior and middle cranial fossae regions were compared for each. Special structures were defined to assess their preservation in both approaches. We used pure endoscopy on the eight sides and with a microscope on those same eight sides. Accessibility was quantified for key structures using linear measurements taken with the navigation system. In addition, we present clinical cases in which an endoscope-assisted supraorbital approach was employed.

RESULTS

Our measurements have been reported for each side in the formalin-fixed heads as the mean ± SD (in mm) from the bone margin to selected regions. Moreover, image analysis was performed using ImageJ software to compare selected surface area measurements between the endoscope and microscope images on each side for all cadaveric available specimens. There were no significant statistical differences between visualization of the selected areas. This means that by visual analysis both endoscopic and microscopic images can provide the surgeon nearly the same visibility and accessibility of a selected region.

CONCLUSION

A pure endoscopic method can be used to conduct the supraorbital keyhole approach when the endoscope is used as a primary tool. Our recommendation is to use the measurements described in this study for preoperative planning of the keyhole approach. We believe that with advances in neuro-endoscope technology, and instrumentations, the endoscopic approach may replace the microscopic approach in the near future.

Evolution of the graded repair of CSF leaks and skull base defects in endonasal endoscopic tumor surgery: trends in repair failure and meningitis rates in 509 patients

Objective

The authors previously described a graded approach to skull base repair following endonasal microscopic or endoscope-assisted tumor surgery. In this paper they review their experience with skull base reconstruction in the endoscopic era.

Methods

A retrospective review of a single-institution endonasal endoscopic patient database (April 2010–April 2017) was undertaken. Intraoperative CSF leaks were graded based on size (grade 0 [no leak], 1, 2, or 3), and repair technique was documented across grades. The series was divided into 2 epochs based on implementation of a strict perioperative antibiotic protocol and more liberal use of permanent and/or temporary buttresses; repair failure rates and postoperative meningitis rates were assessed for the 2 epochs and compared.

Results

In total, 551 operations were performed in 509 patients for parasellar pathology, including pituitary adenoma (66%), Rathke’s cleft cyst (7%), meningioma (6%), craniopharyngioma (4%), and other (17%). Extended approaches were used in 41% of cases. There were 9 postoperative CSF leaks (1.6%) and 6 cases of meningitis (1.1%). Postoperative leak rates for all 551 operations by grade 0, 1, 2, and 3 were 0%, 1.9%, 3.1%, and 4.8%, respectively. Fat grafts were used in 33%, 84%, 97%, and 100% of grade 0, 1, 2, and 3 leaks, respectively. Pedicled mucosal flaps (78 total) were used in 2.6% of grade 0–2 leaks (combined) and 79.5% of grade 3 leaks (60 nasoseptal and 6 middle turbinate flaps). Nasoseptal flap usage was highest for craniopharyngioma operations (80%) and lowest for pituitary adenoma operations (2%). Two (3%) nasoseptal flaps failed. Contributing factors for the 9 repair failures were BMI ≥ 30 (7/9), lack of buttress (4/9), grade 3 leak (4/9), and postoperative vomiting (4/9). Comparison of the epochs showed that grade 1–3 repair failures decreased from 6/143 (4.1%) to 3/141 (2.1%) and grade 1–3 meningitis rates decreased from 5 (3.5%) to 1 (0.7%) (p = 0.08). Prophylactic lumbar CSF drainage was used in only 4 cases (< 1%), was associated with a higher meningitis rate in grades 1–3 (25% vs 2%), and was discontinued in 2012. Comparison of the 2 epochs showed increase buttress use in the second, with use of a permanent buttress in grade 1 and 3 leaks increasing from 13% to 55% and 32% to 76%, respectively (p < 0.001), and use of autologous septal/keel bone as a permanent buttress in grade 1, 2, and 3 leaks increasing from 15% to 51% (p < 0.001).

Conclusions

A graded approach to skull base repair after endonasal surgery remains valid in the endoscopic era. However, the technique has evolved significantly, with further reduction of postoperative CSF leak rates. These data suggest that buttresses are beneficial for repair of most grade 1 and 2 leaks and all grade 3 leaks. Similarly, pedicled flaps appear advantageous for grade 3 leaks, while CSF diversion may be unnecessary and a risk factor for meningitis. High BMI should prompt an aggressive multilayered repair strategy. Achieving repair failure and meningitis rates lower than 1% is a reasonable goal in endoscopic skull base tumor surgery.