Reuse of Nasoseptal Flaps for Endoscopic Endonasal Skull Base Reconstruction

Introduction  Pedicled nasoseptal flap (NSF) placement is a critical component of skull base reconstruction after endoscopic endonasal approaches (EEAs). The effectiveness of NSF reuse has not been thoroughly studied. Prior reports using flaps harvested at one center and reused at another may have technical variability bias. Methods  We identified patients who underwent both their initial and NSF-reused surgeries at Weill Cornell Medical College from 2004 to 2022 using a prospective database of all EEAs. Surgical pathology, intraoperative leak grade, use of cerebrospinal fluid (CSF) diversion and skull base coverage were examined. The primary outcome measure was occurrence of CSF leak. Results  Fourteen patients (six women, eight men) underwent 14 first time and 14 revision operations with median age of 36.6 years (interquartile range [IQR]: 23.9-61.3) at the time of the NSF reuse. The median interval between the first NSF use and reuse was 70.6 months (IQR: 16.6-87). Eight patients were operated on for pituitary adenoma. Nonadenomas included three craniopharyngiomas and one case each of epidermoid, ependymoma, and chordoma. There were 16 high-flow, 8 low-flow intraoperative leaks, and 4 with no leak. CSF diversion was used in 24 operations. There were three postoperative leaks, one after a first operation and two after NSF reuse. All postoperative CSF leaks, whether first or second operations, occurred in cases with both high-flow intraoperative CSF leak and incomplete NSF coverage ( p  = 0.006). Conclusion  NSF reuse is effective at preventing postoperative CSF leak. The primary predictors of leak are high-flow intraoperative leak and inadequate defect coverage with NSF, regardless of the operation number.

Endonasal endoscopic or endoscopic-assisted transcranial surgery of Rathke's cleft cysts: does the approach and surgical technique influence the radicality and recurrence rate?

OBJECTIVE

Resections of symptomatic Rathke's cleft cysts (RCCs) are mainly performed via an endonasal transsphenoidal approach. However, there is a lack of equivalent data in current literature concerning transcranial keyhole approach in the treatment of RCCs. In order to find general recommendations for the surgical treatment of RCCs also with regard to recurrence, the object of this study is the analysis and comparison of both techniques.

METHODS

Twenty-nine patients having been surgically treated between January 2004 and August 2019 were retrospectively analysed. The transsphenoidal approach was chosen in 16 cases and the transcranial keyhole approach in 13 cases. Both surgical techniques were analyzed and compared concerning preoperative symptoms and cyst characteristics, complications, surgical radicality, endocrinological and ophthalmological outcome and recurrences in patients´ follow up.

RESULTS

The postoperative outcome of both techniques was identic and showed highly satisfying success rates with 92% for neurological deficits, 82% for endocrinological dysfunctions and 86% for visual deficits. In contrast, momentous postoperative complications were significantly more likely after transsphenoidal operations. After a mean follow-up time of 5.7 years, the recurrence rates of both cohorts were the same with 0% each.

CONCLUSIONS

Regarding its equal outcome with its lower complication rate, the authors suggest using the supraorbital keyhole approach for RCCs whose anatomical configuration allow both techniques. Yet, the decision should always consider the surgeon's personal experience and other individual patient characteristics. Further studies with higher numbers of cases and longer follow-up periods are necessary to analyse the effect of the selected approach on recurrence.

Interdisciplinary Management of Skull Base Tumors

OBJECTIVE

Endoscopic endonasal skull base surgery has gained acceptance worldwide. Comparative analysis has demonstrated that endoscopic skull base surgery may have advantages for many pathologies of the anterior skull base, e. g., sinonasal malignant tumors; pathologies of the central skull base, e. g., pituitary adenomas, craniopharyngiomas; well-selected cases of planum sphenoidale and tuberculum sellae meningiomas; or for clival lesions, e. g., chordomas, chondrosarcomas, or selected meningiomas. Over the past three decades, interdisciplinary surgical teams, consisting of otolaryngologists and neurosurgeons, have provided detailed anatomical knowledge, suggested new approaches or modifications of established surgical techniques, and offered continued surgical education.

METHOD

A review of pertinent literature was conducted with an emphasis on interdisciplinary endoscopic surgery of skull base lesions.

RESULTS

Based on the authors̓ surgical experience in two different interdisciplinary endoscopic skull base centers, the authors classify approaches for endoscopic endonasal skull base surgery, describe indications, and key anatomic landmarks for common pathologies, and highlight surgical techniques to avoid complications.

CONCLUSION

Interdisciplinary endonasal endoscopic surgery combines surgical expertise, improves resection rates for many pathologies, and minimizes morbidity by reducing the incidence of surgical complications.

[Endoscopic endonasal anterior skull base surgery : Presentation of a monocentric entity profile]

BACKGROUND

Extended endoscopic endonasal surgery (EEES) is an essential part of treatment of various pathologies of the anterior skull base. In addition to significant improvements in the quality of life of affected patients and a lower complication profile compared to open skull base surgery, the therapeutic results are comparable if the indications are correct.

MATERIALS AND METHODS

Data of all endoscopic endonasal skull base procedures performed at the University Skull Base Center Hamburg under the direction of the Department of Otorhinolaryngology between June 2018 and November 2022 were retrospectively collected.

RESULTS

A total of 50 cases were identified. Of these, 56% (28/50) were malignant tumors, 24% (12/50) were benign pathologies with direct skull base involvement, and 20% (10/50) were anterior skull base defects with rhinoliquorrhea. In 96% (48/50) of cases, the preoperatively set goal of surgery (representative biopsy, complete resection, closure of the skull base defect) could be achieved. Complications grade III or higher according to Clavien-Dindo occurred in 4/50 cases. During the observation period, n = 5 olfactory neuroblastomas were diagnosed, all of which were exclusively and successfully operated on endoscopically.

CONCLUSION

In recent years, the spectrum of endoscopically resectable pathologies of the anterior skull base has steadily expanded. In particular, midline-related tumors such as olfactory neuroblastoma or iatrogenic/idiopathic skull base defects with cerebrospinal fluid rhinorrhea are treated completely endoscopically with very good results. Nevertheless, there are also limitations to this technique. Due to high variance in the scope of frontobasal surgery, the extent, and the complex anatomy, as well as the overlapping responsibilities of the specialist disciplines, establishment of certified skull base centers and bundling of frontobasal surgery at these centers is highly relevant for quality assurance.

Comparison of the Endoscopic Endonasal Approach with the Endoscopic Supraorbital Keyhole Approach to the Tuberculum Sellae Region: A Quantitatively Cadaveric Study

BACKGROUND

 The endoscopic endonasal approach (EEA) and the endoscopic supraorbital keyhole approach (eSKA) provide minimally invasive access to tuberculum sellae (TS) tumors. Evaluation of the operating maneuverability is helpful for approach selection. Herein, we compared the two approaches and aimed to provide quantitative anatomic data for surgical decision-making in the management of TS lesions.

METHODS

 Fifteen dissections were performed on five silicone-injected cadaveric heads. The EEA and eSKA (both right and left) were performed on each head. Surgical freedom and working angles in the axial and sagittal planes were calculated using the stereotactic navigation system in the selected six targets: the midpoint of the leading edge of the sphenoid sinus (leSS), the midpoint of the edge of the dorsum sellae (eDS), the ipsilateral medial opticocarotid recess (imOCR), the contralateral medial opticocarotid recess (cmOCR), the ipsilateral lateral opticocarotid recess (ilOCR), and the contralateral lateral opticocarotid recess (clOCR).

RESULTS

 The surgical freedom at the ilOCR and the axial working angles at the leSS, ilOCR, and imOCR (imOCR with excessive manipulation of the optic apparatus) were greater in the eSKA. The EEA provided greater surgical freedom and/or working angles at most targets than eSKA (the surgical freedom at the imOCR, cmOCR, clOCR, and eDS; the axial working angles at the cmOCR and clOCR; and the sagittal working angles at the leSS, imOCR, cmOCR, clOCR, and eDS).

CONCLUSION

 The EEA provides greater surgical freedom and working angles for paramedian lesions, whereas the eSKA provides better surgical maneuverability for lesions with lateral extension.

Multilayer Anterior Skull Base Reconstruction with Cortical Rib Bone Graft: Preliminary Experience

OBJECTIVE

During the past decades, different methods have been described for anterior skull base reconstruction. Regarding larger skull base defects, few investigators have described the use of bone grafts to foster support and prevent frontal lobe sagging, herniation, or falling. The aim of this study is to describe the use of a rib bone graft, which could be an option in these cases due to its rigidity and dimensions.

METHODS

We retrospectively collected preoperative, intraoperative, and postoperative data at the last follow-up of 10 patients who underwent multilayer anterior skull base reconstruction, including rib bone graft, for large anterior cranial base defects at 2 tertiary care academic hospitals.

RESULTS

Eight patients underwent endoscopic craniectomy for sinonasal malignancies, and the other two underwent transnasal endoscopic surgery for congenital meningoencephalocele. Anterior skull base defects measured on average 3.8 cm ± 0.9 SD antero-posteriorly (range 2.5-5 cm) and 2.3 ± 0.9 SD latero-laterally (range 0.9-4 cm). Multilayer reconstruction was performed in all cases, including a rib bone graft positioned as intracranial extradural layer. No patient experienced thoracic complications during the postoperative period. No side effects related to the bone graft or meningoencephalocele occurrence were reported after a mean follow-up of 8.0 ± 6.3 months.

CONCLUSIONS

The use of a cortical rib bone graft could be a safe and effective option in skull base reconstruction when managing large defects after cancer removal.

Surgical Anatomy and Approaches of the Anterior Cranial Fossa from a Transcranial and Endonasal Perspective

The anterior cranial fossa (ACF) is a complex anatomical region that can be affected by a broad spectrum of pathology. For the surgical treatment of these lesions, many approaches have been described, each of them with different scope and potential surgical complications, often associated with significant morbidity. Traditionally, tumors involving the ACF have been operated by transcranial approaches; however, in the last two decades, endoscopic endonasal approaches (EEAs) have been gaining popularity. In this work, the authors review and describe the anatomical aspects of the ACF and the technical nuances of transcranial and endoscopic approaches for tumors located in this region. Four approaches were performed in embalmed cadaveric specimens and the key steps were documented. Four illustrative cases of ACF tumors were selected to demonstrate the clinical application of anatomical and technical knowledge, which are essential in the preoperative decision-making process.

Olfactory Groove Meningiomas: Comprehensive assessment between the different microsurgical transcranial approaches and the Endoscopic Endonasal Approaches, systematic review and metanalysis on behalf of the EANS skull base section

•OGM surgery is much more complex than a simple debate of "from above or from below" (transcranial vs endoscopic).•Lateral Sub-frontal and Superior Interhemispheric seem the most effective, superior and versatile approaches for OGM.•Minimally Invasive Transcranial approaches showed no inferiority in OGM sized <4 ​cm.•Endoscopic Endonasal Approaches showed inferior results in surgical and in functional outcomes for OGM.

Giant Non-Functioning Pituitary Adenomas: Treatment Considerations

Giant pituitary adenomas are a subgroup of pituitary adenomas defined by a diameter greater than 4 cm, and they account for 5-14% of adenomas in surgical series. Because of their growth patterns and locations, often involving critical neurovascular structures, they represent a true surgical challenge, and gross total resection is difficult to achieve. There is no consensus on the optimal surgical strategy for giant pituitary adenomas, and, often, integrated multi-staged treatment strategies have been considered. Transcranial or transsphenoidal approaches, alone or combined, according to tumor and patient features are the two main routes. Each of these strategies has pros and cons. The conventional transcranial approach has for a long time been considered the first choice for the removal of giant pituitary adenomas. Currently, with endoscopic techniques, it is also possible to remove lesions that involve the intradural compartment and the adjacent neurovascular structures with the use of extended approaches. Our policy for the management of these lesions is to adopt the endoscopic endonasal approach as the first choice unless the tumor presents significant intracranial extension that results in it being outside the visibility and maneuverability of the endoscopic endonasal route. In these latter cases, we agree that the transcranial approach is more appropriate. However, accurate preoperative evaluation and refined treatment plans for each patient are mandatory to define a proper strategy in order to achieve the most effective long-term result.

Endonasal transsphenoidal surgery for planum sphenoidale versus tuberculum sellae meningiomas

OBJECTIVE

The aim of this study was to determine if the distinction between planum sphenoidale (PS) and tuberculum sellae (TS) meningiomas is clinically meaningful and impacts the results of the endoscopic endonasal approach (EEA).

METHODS

A consecutive series of patients who were 18 years of age or older and underwent EEA for newly diagnosed grade I PS meningiomas (PSMs) and TS meningiomas (TSMs) between October 2007 and May 2021 were included. The PS and TS were distinguished by drawing a line passing through the center of the TS and perpendicular to the PS on postcontrast T1-weighted MRI. Probabilistic heatmaps were created to display the actual distribution of tumor volumes. Tumor volume, extent of resection (EOR), visual outcome, and complications were assessed.

RESULTS

The 47 tumors were distributed in a smooth continuum. Using an arbitrary definition, 24 (51%) were PSMs and 23 (49%) were TSMs. The mean volume of PSMs was 5.6 cm3 compared with 4.5 cm3 for TSMs. Canal invasion was present in 87.5% of PSMs and 52% of TSMs. GTR was achieved in 38 (84%) of 45 cases in which it was the goal, slightly less frequently for PSMs (78%) compared with TSMs (91%), although the difference was not significant. Th mean EOR was 99% ± 2% for PSMs and 98% ± 11% for TSMs. Neither the suprasellar notch angle nor the percentage of tumor above the PS impacted the rate of GTR. After a median follow-up of 28.5 months (range 0.1–131 months), there were 2 (5%) recurrences after GTR (n = 38) both of which occurred in patients with PSMs. Forty-two (89%) patients presented with preoperative impaired vision. Postoperative vision was stable or improved in 96% of patients with PSMs and 91% of patients with TSMs. CSF leakage occurred in 4 (16.6%) patients with a PSM, which resolved with only lumbar drainage, and in 1 (4.3%) patient with a TSM, which required reoperation.

CONCLUSIONS

PSM and TSMs arise in a smooth distribution, making the distinction arbitrary. Those classified as PSMs were larger and more likely to invade the optic canals. Surgical outcome for both locations was similar, slightly favoring TSMs. The arbitrary distinction between PSMs and TSMs is less useful at predicting outcome than the lateral extent of the tumor, regardless of the site of origin.

Critical appraisal of minimally invasive keyhole surgery for intracranial meningioma in a large case series

Background

Meningioma surgery has evolved over the last 20 years with increased use of minimally invasive approaches including the endoscopic endonasal route and endoscope-assisted and gravity-assisted transcranial approaches. As the “keyhole” concept remains controversial, we present detailed outcomes in a cohort series.

Methods

Retrospective analysis was done for all patients undergoing meningioma removal at a tertiary brain tumor referral center from 2008–2021. Keyhole approaches were defined as: use of a minimally invasive “retractorless” approach for a given meningioma in which a traditional larger approach is often used instead. The surgical goal was maximal safe removal including conservative (subtotal) removal for some invasive locations. Primary outcomes were resection rates, complications, length of stay and Karnofsky Performance Scale (KPS). Secondary outcomes were endoscopy use, perioperative treatments, tumor control and acute MRI FLAIR/T2 changes to assess for brain manipulation and retraction injury.

Results

Of 329 patients, keyhole approaches were utilized in 193(59%) patients (mean age 59±13; 30 (15.5%) had prior surgery) who underwent 213 operations; 205(96%) were skull base location. Approaches included: endoscopic endonasal (n = 74,35%), supraorbital (n = 73,34%), retromastoid (n = 38,18%), mini-pterional (n = 20,9%), suboccipital (n = 4,2%), and contralateral transfalcine (n = 4,2%). Primary outcomes: Gross total/near total (>90%) resection was achieved in 125(59%) (5% for petroclival, cavernous sinus/Meckel’s cave, spheno-cavernous locations vs 77% for all other locations). Major complications included: permanent neurological worsening 12(6%), CSF leak 2(1%) meningitis 2(1%). There were no DVTs, PEs, MIs or 30-day mortality. Median LOS decreased from 3 to 2 days in the last 2 years; 94% were discharged to home with favorable 90-day KPS in 176(96%) patients. Secondary outcomes: Increased FLAIR/T2 changes were noted on POD#1/2 MRI in 36/213(17%) cases, resolving in all but 11 (5.2%). Endoscopy was used in 87/139(63%) craniotomies, facilitating additional tumor removal in 55%. Tumor progression occurred in 26(13%) patients, mean follow-up 42±36 months.

Conclusions & relevance

Our experience suggests minimally invasive keyhole transcranial and endoscopic endonasal meningioma removal is associated with comparable resection rates and low complication rates, short hospitalizations and high 90-day performance scores in comparison to prior reports using traditional skull base approaches. Subtotal removal may be appropriate for invasive/adherent meningiomas to avoid neurological deficits and other post-operative complications, although longer follow-up is needed. With careful patient selection and requisite experience, these approaches may be considered reasonable alternatives to traditional transcranial approaches.

Endoscopic transorbital eyelid approach for the removal of an extraconal cavernous venous malformation: Case report

Cavernous venous malformations (CVMs) are one of the most common benign primary orbital lesions in adults and the second most frequent cause of unilateral proptosis. Extraconal location is extremely rare, representing a favorable condition as compared to intraconal, as lesions at this level often adhere to orbital muscles and optic nerve. Herein, we report the case of a 50-year-old patient, who came to our attention because of progressive painless right axial proptosis. Magnetic resonance images were consistent with an extraconal CVM, occupying the superior temporal compartment of the orbit. Successful removal of the lesion was achieved through an endoscopic transorbital eyelid approach. The present case confirms the safety and efficacy of the endoscopic transorbital eyelid approach.

The Endoscopic-Assisted Supraorbital Approach for Resection of Anterior Skull Base Meningiomas: A Large Single-Center Retrospective Surgical Study

Objective The endoscopic-assisted supraorbital approach (eSOA) constitutes a minimally invasive strategy for removing anterior skull base meningiomas (ASBM). We present the largest retrospective single-institution and long-term follow-up study of eSOA for ASBM resection, providing further insight regarding indication, surgical considerations, complications, and outcome.

Methods We evaluated data of 176 patients operated on ASBM via the eSOA over 22 years.

Results Sixty-five tuberculum sellae (TS), 36 anterior clinoid (AC), 28 olfactory groove (OG), 27 planum sphenoidale, 11 lesser sphenoid wing, seven optic sheath, and two lateral orbitary roof meningiomas were assessed. Median surgery duration was 3.35 ± 1.42 hours, being significantly longer for OG and AC meningiomas (p <0.05). Complete resection was achieved in 91%. Complications included hyposmia (7.4%), supraorbital hypoesthesia (5.1%), cerebrospinal fluid fistula (5%), orbicularis oculi paresis (2.8%), visual disturbances (2.2%), meningitis (1.7%) and hematoma and wound infection (1.1%). One patient died due to intraoperative carotid injury, other due to pulmonary embolism. Median follow-up was 4.8 years with a tumor recurrence rate of 10.8%. Second surgery was chosen in 12 cases (10 via the previous SOA and two via pterional approach), whereas two patients received radiotherapy and in five patients a wait-and-see strategy was adopted.

Conclusion The eSOA represents an effective option for ASBM resection, enabling high complete resection rates and long-term disease control. Neuroendoscopy is fundamental for improving tumor resection while reducing brain and optic nerve retraction. Potential limitations and prolonged surgical duration may arise from the small craniotomy and reduced maneuverability, especially for large or strongly adherent lesions.

Midline Skull Base Meningiomas: Transcranial and Endonasal Perspectives

Simple Summary

Skull base meningiomas have always represented a challenge for neurosurgeons. Despite their histological nature, they may be associated with unfavorable outcomes due to their deep-seated location and the surrounding neurovascular structures. Over time, several corridors have been proposed, each one carrying its own pros and cons. During the last decades, the endoscopic endonasal route has been asserted among the classic routes for a growing number of midline and paramedian lesions. Therefore, the aim of our paper is to present a comprehensive review of the indications and techniques for the management of skull base meningiomas, emphasizing the ambivalent and complementary role of the low and high routes.

Abstract

Skull base meningiomas have always represented a challenge for neurosurgeons. Despite their histological nature, they may be associated with unfavorable outcomes due to their deep-seated location and the surrounding neurovascular structures. The state of the art of skull base meningiomas accounts for both transcranial, or high, and endonasal, or low, routes. A comprehensive review of the pertinent literature was performed to address the surgical strategies and outcomes of skull base meningioma patients treated through a transcranial approach, an endoscopic endonasal approach (EEA), or both. Three databases (PubMed, Ovid Medline, and Ovid Embase) have been searched. The review of the literature provided 328 papers reporting the surgical, oncological, and clinical results of different approaches for the treatment of skull base meningiomas. The most suitable surgical corridors for olfactory groove, tuberculum sellae, clival and petroclival and cavernous sinus meningiomas have been analyzed. The EEA was proven to be associated with a lower extent of resection rates and better clinical outcomes compared with transcranial corridors, offering the possibility of achieving the so-called maximal safe resection.

Olfactory Outcomes after Resection of Tuberculum Sella and Planum Sphenoidale Meningiomas via a Transcranial Approach

Objectives Controversy exists surrounding the optimal approaches to tuberculum sella meningioma (TSM) and planum meningioma (PM). Olfaction is infrequently considered within this context but is nonetheless an important quality of life measure. The evolution of olfactory outcomes following contemporary transcranial surgery remains unclear. This study reviews olfactory outcomes after supraorbital craniotomy for TSM or PM and defines temporal trends in its recovery.

Study Design A prospective study of a patients who underwent a minimally invasive supraorbital craniotomy for TSM or PM was conducted at a single neurosurgical center.

Participants & Main Outcome Measures All patients were questioned about olfaction at presentation 3 months postoperatively, 12 months postoperatively, and annually thereafter (median follow-up = 37 months). The olfactory status of patients was categorized as normosmia, anosmia, hyposmia, parosmia, (altered perception of odours), or phantosmia, (olfactory hallucinations).

Results Twenty-two patients were included in the study analysis, (range = 27–76). Precisely, 3 months after surgery, seven patients had normal olfaction (32%). Six patients were anosmic, (27%) four hyposmic, (18%), three parosmic, (14%), and two were phantosmic (9%). At 1-year follow-up, almost half of patients (10; 48%) were normosmic, while two patients (9.5%) were anosmic. There were no further improvements in olfaction between 1 year and long-term follow-up.

Conclusion Subfrontal transcranial approaches for TSM or PM appear to be associated with changes in olfaction that can improve with time; these improvements occur within the first year after surgery. Impacts upon olfaction should be considered when selecting a surgical approach and patients counseled appropriately.

Anatomical Study of Ethmoidal Foramina and Optic Canal in Endoscopic Trans-Nasal Approach to Anterior Skull Base

BACKGROUND

Surgery to anterior skull base is challenging since complex structures are involved. Injury of olfactory fila and optic nerve may result in postoperative complications. In our study, the authors aim to use computer topographic image to provide a comprehensive anatomical information of anterior skull base and set up a new classification of optic canal (OC) in ethmoid sinus by the degree of bony defect, so as to help surgeons in endoscopic transnasal approach to anterior skull base.

METHOD

Computer topographic angiography images of 112 individuals were reviewed, the measurement was performed on coronal, sagittal, and axis planes after the multiplanar reformation. Nostril and mid-sagittal lines were used to locate the anterior, middle, and posterior part of ethmoidal foramina and orbital opening of OC. Further, the authors classified OC in ethmoidal sinus into 4 types by the degree of the bony defect.

RESULT

Distance between nostril to anterior, middle, and posterior part of ethmoidal foramina and OC are 6.23 ± 0.21, 6.62 ± 0.26, 7.29 ± 0.25, and 7.76 ± 0.41 mm, respectively. Angle between line from nostril to ethmoidal foramina and horizontal plane are 47.50° ± 1.03°, 41.67° ± 1.33°, 37.20° ± 1.34°, respectively. For the 4 types of OC, the percentage is 15.6%, 11.6%, 31.3%, and 41.5%, respectively.

CONCLUSIONS

Our findings provide anatomical information of ethmoidal foramina and OC during endoscopic transnasal approach to anterior skull base, on the basis of some fixed anatomical landmarks. So as to enhance the surgical safety of this procedure and aid in the choice of the appropriate endoscopic equipment for the procedure.

Minimally Invasive Approaches to Anterior Skull Base Meningiomas

Objective Anterior skull base meningiomas include olfactory groove, planum sphenoidale, and tuberculum sellae lesions. Traditionally, standard craniotomy approaches have been used to access meningiomas in these locations. More recently, minimally invasive techniques including supraorbital and endonasal endoscopic approaches have gained favor; however there are limited published series comparing the use of these two techniques for these meningiomas. Using our patent database, we identified patients who underwent these two approaches, and conducted a retrospective chart review to compare outcomes between these two techniques.

Methods A total of 32 patients who underwent minimally invasive approaches were identified: 20 supraorbital and 11 endoscopic endonasal. Radiographic images, presenting complaints and outcomes, were analyzed retrospectively. The safety of each approach was evaluated.

Results The mean extent of resection through a supraorbital approach was significantly greater than that of the endoscopic endonasal approach, 88.1 vs. 57.9%, respectively (p = 0.016). Overall, preoperative visual acuity and anopsia deficits were more frequent in the endonasal group that persisted postoperatively (visual acuity: p = 0.004; anopsia: p = 0.011). No major complications including cerebrospinal fluid (CSF) leaks or wound-related complications were identified in the supraorbital craniotomy group, while the endonasal group had two CSF leaks requiring lumbar drain placement. Length of stay was shorter in the supraorbital group (3.4 vs. 6.1 days, p < 0.001).

Conclusion Anterior skull base meningiomas can be successfully managed by both supraorbital and endoscopic endonasal approaches. Both approaches provide excellent direct access to tumor in carefully selected patients and are safe and efficient, but patient factors and symptoms should dictate the approach selected.

Managing Arterial Injury in Endoscopic Skull Base Surgery: Case Series and Review of the Literature

BACKGROUND

The most feared complications following endoscopic endonasal skull base surgery are arterial vascular injuries. Previously published literature is restricted to internal carotid artery injuries. The ideal method for controlling arterial bleeding during this kind of procedure is debated, and a variety of techniques have been advocated.

OBJECTIVE

To evaluate the management and outcome following intraoperative arterial injury during endoscopic endonasal skull base surgery.

METHODS

We performed a retrospective review of a prospectively acquired database of consecutive endonasal endoscopic surgeries at the New York-Presbyterian Hospital/Weill Cornell Medical Center from December 2003 to June 2015 and identified all cases of arterial injury.

RESULTS

Of 800 cases, there were 4 arterial injuries (0.5%), of which only one involved the internal carotid artery (ICA), for a risk of 0.125%. The other 3 involved the ophthalmic artery, anterior communicating artery, and A1 segment of the anterior cerebral artery. In all cases, definitive treatment involved occlusion of the artery either through endovascular means (3 cases) or direct surgical ligation (1 case). Neurological examinations were unchanged after arterial repair with only 1 small asymptomatic stroke. Literature review identified 7336 patients, of which there were 25 arterial injuries, of which 19 were of the ICA. Hence, the total rate of arterial injury was 0.34% and the rate of ICA injury was 0.26%. Arterial sacrifice was the only reliable method for managing arterial injury.

CONCLUSION

Arterial injury is an uncommon event after endoscopic endonasal surgery. Attempts at arterial repair are rarely successful, and vessel sacrifice is the most reliable technique at this point.

Sinonasal outcome after endoscopic mononostril transsphenoidal surgery: A single center cohort study

OBJECTIVE

The endoscopic endonasal approach has been well established for skull base surgery. However, there are only few studies pointing out nasal complaints after surgery. In this study, the authors evaluated postoperative nasal complaints and complications after mononostril endoscopic procedures.

METHODS

All patients operated on parasellar and sellar pathologies at our department via an endoscopic mononostril transnasal transsphenoidal approach from January 2011 to May 2015 were analyzed. To assess specific postoperative nasal pathological conditions and complaints, a questionnaire was established. Applicable data of 79 patients with additional ENT follow-up could be included. Endpoints were the quantitative evaluation of complications and correlation of these data.

RESULTS

There was no vascular injury or worsening of visual function. Two patients had persisting CSF fistula and one of them meningitis. There was a significant decrease of nasal complaints during follow up after 2 years (p < 0.001). Further surgical treatment by ENT physician was necessary in 11.4%. Resurgery significantly increased the risk of postsurgical complaints (p < 0.005). The use of a tamponade significantly reduced the risk of postsurgical reduced nasal airflow (p = 0.026) and sinusitis (p = 0.002).

CONCLUSIONS

Endoscopic endonasal procedures to skull base lesions achieve high radicality with low complication rates. However, they induce temporary and permanent nasal complaints and complications. Thereby, resurgeries increase the risk of nasal complaints and the use of nasal tamponades might increase the sinonasal outcome. Further prospective studies are necessary to objectify the evaluation of postsurgical nasal complications.

The Impact of Age on Long-Term Quality of Life After Endonasal Endoscopic Resection of Skull Base Meningiomas

BACKGROUND

Midline ventral skull base meningiomas may be amenable to an endonasal endoscopic approach, which has theoretical advantages and may help preserve quality of life (QOL) when compared with transcranial approaches.

OBJECTIVE

To investigate the effect of age on QOL following endonasal endoscopic surgery, given the documented impact of age on QOL outcomes following transcranial resection of midline ventral skull base meningiomas.

METHODS

We reviewed a prospectively acquired database of endonasal endoscopic surgery for meningiomas. Inclusion criteria included patients who had completed long-term postoperative (≥6 months follow-up) QOL questionnaires (Anterior Skull Base Questionnaire [ASBQ] and Sino-Nasal Outcome Test [SNOT-22]). Postoperative QOL scores were also compared with preoperative QOL in a patient subset.

RESULTS

Long-term QOL data were available in 34 patients. Average postoperative ASBQ and SNOT-22 scores were 3.39 and 23.0, respectively. Better QOL was statistically associated with age <55 (P = .02). In a subset of patients, preoperative and postoperative ASBQ and SNOT-22 scores were compared. Only SNOT-22 scores significantly increased from 15.9 + 20.8 to 25.9 + 19.5 (P = .04).

CONCLUSION

We report the first study specifically evaluating long-term QOL after endonasal endoscopic resection of skull base meningiomas. QOL was decreased postoperatively in patients aged ≥55.

ABBREVIATIONS

ASBQ, Anterior Skull Base QuestionnaireGTR, gross total resectionQOL, quality of lifeSNOT-22, 22-item Sino-Nasal Outcome Test.

Surgical anatomy and utility of pedicled vascularized tissue flaps for multilayered repair of skull base defects

OBJECT The objective of this study was to describe the surgical anatomy and technical nuances of various vascularized tissue flaps. METHODS The surgical anatomy of various tissue flaps and their vascular pedicles was studied in 5 colored silicone-injected anatomical specimens. Medical records were reviewed of 11 consecutive patients who underwent repair of extensive skull base defects with a combination of various vascularized flaps. RESULTS The supraorbital, supratrochlear, superficial temporal, greater auricular, and occipital arteries contribute to the vascular supply of the pericranium. The pericranial flap can be designed based on an axial blood supply. Laterally, various flaps are supplied by the deep or superficial temporal arteries. The nasoseptal flap is a vascular pedicled flap based on the nasoseptal artery. Patients with extensive skull base defects can undergo effective repair with dual flaps or triple flaps using these pedicled vascularized flaps. CONCLUSIONS Multiple pedicled flaps are available for reconstitution of the skull base. Knowledge of the surgical anatomy of these flaps is crucial for the skull base surgeon. These vascularized tissue flaps can be used effectively as single or combination flaps. Multilayered closure of cranial base defects with vascularized tissue can be used safely and may lead to excellent repair outcomes.

Endoscopic Endonasal Transclival Transcondylar Approach for Foramen Magnum Meningiomas

BACKGROUND

The endoscopic endonasal approach provides a direct route to ventral foramen magnum (FM) lesions like meningiomas, which are difficult to access. Endonasal access at the FM is limited laterally by the occipital condyles and inferiorly by the C1 anterior arch and the odontoid process, which may need partial resection.

OBJECTIVE

We investigated the surgical anatomy and technical nuances for endonasally increasing the surgical corridor at the FM region both laterally and inferiorly. Unique to our report, we quantified the amount of required medial condyle resection to obtain exposure of the lateral aspects of the FM.

METHODS

Five fresh human head silicone-injected specimens underwent endonasal inferior transclival, transcondylar approaches. The lateral limit of medial condyle resection was defined using a vertical line extending inferiorly from foramen lacerum and its intersection with the occipital condyle. The condylectomy was limited posteriorly by the cortical bone surrounding the hypoglossal canal. The volume of the resected condyle (cubic centimeters) for 10 sides was measured using the pre- and postdissection computed tomography-volumetric analysis.

RESULTS

The mean percentage condylar volume resected during a unilateral medial condylectomy was 18% (9.7%-28.3%). The surgical corridor was extended inferiorly in all specimens without violating the transverse ligament by drilling the superior aspects of C1 anterior arch and the exposed odontoid tip. These operative nuances were successfully applied in the operating room.

CONCLUSION

Anatomical landmarks can reliably guide an endonasal anteromedial condyle resection. Minimal condyle resection is required to widen lateral access at the FM, which minimizes the risk of craniocervical instability.

Endoscope-assisted endonasal versus supraorbital keyhole resection of olfactory groove meningiomas: comparison and combination of 2 minimally invasive approaches

OBJECTIVE

Although the endonasal endoscopic approach has been applied to remove olfactory groove meningiomas, controversy exists regarding the efficacy and safety of this approach compared with more traditional transcranial approaches. The endonasal endoscopic approach was compared with the supraorbital (eyebrow) keyhole technique, as well as a combined "above-and-below" approach, to evaluate the relative merits of each approach in different situations.

METHODS

Nineteen cases were reviewed and divided according to operative technique into 3 different groups: purely endonasal (6 cases); supraorbital eyebrow (microscopic with endoscopic assistance; 7 cases); and combined endonasal endoscopic with either the bicoronal or eyebrow microscopic approach (6 cases). Resection was judged on postoperative MRI using volumetric analysis. Tumors were assessed based on the Mohr radiological classification and the presence of the lion's mane sign.

RESULTS

The mean age at surgery was 61.4 years. The mean tumor volume was 19.6 cm(3) in the endonasal group, 33.5 cm(3) in the supraorbital group, and 37.8 cm(3) in the combined group. Significant frontal lobe edema was identified in 10 cases (52.6%). The majority of tumors were either Mohr Grade II (moderate) (42.1%) or Grade III (large) (47.4%). Gross-total resection was achieved in 50% of the endonasal cases, 100% of the supraorbital eyebrow cases with endoscopic assistance, and 66.7% of the combined cases. The extent of resection was 87.8% for the endonasal cases, 100% for the supraorbital eyebrow cases, and 98.9% for the combined cases. Postoperative anosmia occurred in 100% of the endonasal and combined cases and only 57.1% of the supraorbital eyebrow cases. Excluding anosmia, permanent complications occurred in 83.3% of the cases in the endoscopic group, 0% of the cases in the supraorbital eyebrow group, and 16.7% of cases in the combined group (p = 0.017). There were 3 tumor recurrences: 2 in the endonasal group and 1 in the combined group.

CONCLUSIONS

The supraorbital eyebrow approach, with endoscopic assistance, leads to a higher extent of resection and lower rate of complications than the purely endonasal endoscopic approach. The endonasal endoscopic approach by itself may be suitable for a small percentage of cases. The combined above-and-below approaches are useful for large tumors with invasion of the ethmoid sinuses.

Septal transposition: a novel technique for preservation of the nasal septum during endoscopic endonasal resection of olfactory groove meningiomas

Endonasal resection of olfactory groove meningiomas allows for several advantages over transcranial routes, including a direct approach to the bilateral anterior cranial base and dura mater, early tumor devascularization, and avoidance of brain retraction. Although considered minimally invasive, the endoscopic approach to the cribriform plate typically requires resection of the superior nasal septum, resulting in a large superior septal perforation. The septal transposition technique improves preservation of sinonasal anatomy through the elimination of a septal perforation while allowing for wide exposure to the midline anterior cranial base and harvest of a nasal septal flap. Herein, the authors describe a 39-year-old female who presented with a progressively enlarging olfactory groove meningioma. An endoscopic endonasal resection with a septal transposition technique was performed. On follow-up, the nasal cavity had completely normal anatomy with preservation of the turbinates and nasal septum. The authors conclude that septal transposition is a useful technique that allows wide exposure of the anterior cranial base with maximal preservation of normal nasal anatomy and avoidance of a large septal perforation.

Endoscopic endonasal surgery for olfactory groove meningiomas: outcomes and limitations in 50 patients

OBJECT

Recently, endoscopic endonasal surgery (EES) has been introduced in the management of skull base tumors, with constantly improving outcomes and increasing indications. The authors retrospectively reviewed the effectiveness of EES in the management of olfactory groove meningiomas.

METHODS

Between February 2003 and December 2012, 50 patients (64% female) with olfactory groove meningiomas underwent EES at the University of Pittsburgh Medical Center. The authors present the results of EES and analyze the resection rates, clinical outcome, complications, and limitations of this approach.

RESULTS

Forty-four patients presented with primary tumors, whereas six were previously treated elsewhere. The patients' mean age was 57.1 years (range 27-88 years). Clinical presentation included altered mental status (36%), visual loss (30%), headache (24%), and seizures (20%). The mean maximum tumor diameter was 41.6 mm (range 18-80 mm). All patients underwent EES, which was performed in stages in 18 giant tumors. Complete tumor resection (Simpson Grade I) was achieved in 66.7% of the 45 patients in whom it was the goal, and 13 (28.9%) had neartotal resection (> 95% of the tumor). Tumor size, calcification, and absence of cortical cuff from vasculature were significant factors that influenced the degree of resection (p = 0.002, p = 0.024, and p = 0.028, respectively). Tumor residual was usually at the most lateral and anterior tumor margins. Following EES, mental status was improved or normalized in 77.8% of the cases, vision was improved or restored in 86.7%, and headaches resolved in 83.3%. There was no postoperative deterioration of presenting symptoms. Complications were increased in tumors > 40 mm and included CSF leakage (30%), which was significantly associated with lobular tumor configuration (p = 0.048); pulmonary embolism/deep vein thrombosis, more commonly in elderly patients (20%); sinus infections (10%); and delayed abscess months or years after EES (6%). One patient had an intraoperative vascular injury resulting in transient hemiparesis (2%). There were no perioperative deaths. During a mean follow-up period of 32 months (median 22 months, range 1-115 months), 1 patient underwent repeat EES for tumor regrowth.

CONCLUSIONS

Endoscopic endonasal surgery has shown good clinical outcomes regardless of patient age, previous treatment, or tumor characteristics. Tumor size > 40 mm, calcification, and absence of cortical vascular cuff limit GTR with EES; in addition, large tumors are associated with increased postoperative complications. Significant lateral and anterior dural involvement may represent indications for using traditional craniotomies for the management of these tumors. Postoperative CSF leakage remains a problem that necessitates innovations in EES reconstruction techniques.

Endoscopic endonasal resection of skull base meningiomas: the significance of a "cortical cuff" and brain edema compared with careful case selection and surgical experience in predicting morbidity and extent of resection

OBJECT

This paper describes a consecutive series of skull base meningiomas resected using an endoscopic endonasal approach through various corridors at a single institution over 7 years. The impact of case selection and experience, the presence of a cortical cuff between the tumor and surrounding vessels, and brain edema on morbidity and rates of gross-total resection (GTR) were examined.

METHODS

A retrospective review of a series of 46 skull base meningiomas from a prospective database was conducted. The series of cases were divided by location: olfactory groove (n = 15), tuberculum and planum (n = 20), sellar/cavernous (n = 9) and petroclival (n = 2). Gross-total resection was never intended in the sellar/cavernous tumors, which generally invaded the cavernous sinus. Clinical charts, volumetric imaging, and pathology were reviewed to assess the extent of resection and complications. Cases were divided based on a time point in which surgical technique and case selection improved into Group 1 (surgery prior to June 2008; n = 21) and Group 2 (surgery after June 2008; n = 25) and into those with and without a cortical cuff and with and without brain edema.

RESULTS

Improved case selection had the greatest impact on extent of resection. For the entire cohort, rates of GTR went from 38% to 76% (p = 0.02), and for cases in which GTR was the intent, the rates went from 63% to 84% (not significant), which was mostly driven by the planum and tuberculum meningiomas, which went from 75% to 91.7 % (nonsignificant difference). The presence of a cortical cuff and brain edema had no impact on outcomes. There were 3 CSF leaks (6.5%) but all were in Group 1. Hence, CSF leak improved from 14.2% to 0% with surgical experience. Lessons learned for optimal case selection are discussed.

CONCLUSIONS

Surgical outcome for endonasal endoscopic resection of skull base meningiomas depends mostly on careful case selection and surgical experience. Imaging criteria such as the presence of a cortical cuff or brain edema are less important.

Craniotomy for anterior cranial fossa meningiomas: historical overview

The surgical treatment of meningiomas located at the base of the anterior cranial fossa is often challenging, and the evolution of the surgical strategy to resect these tumors parallels the development of craniotomy, and neurosurgery in general, over the past century. Early successful operations to treat these tumors were pioneered by prominent figures such as Sir William Macewen and Francesco Durante. Following these early reports, Harvey Cushing made significant contributions, allowing a better understanding and treatment of meningiomas in general, but particularly those involving the anterior cranial base. Initially, large-sized unilateral or bilateral craniotomies were necessary to approach these deep-seated lesions. Technical advances such as the introduction of electrosurgery, the operating microscope, and refined microsurgical instruments allowed neurosurgeons to perform less invasive surgical procedures with better results. Today, a wide variety of surgical strategies, including endoscopic surgery and radiosurgery, are used to treat these tumors. In this review, the authors trace the evolution of craniotomy for anterior cranial fossa meningiomas.

Endoscopic endonasal surgery for suprasellar meningiomas: experience with 75 patients

OBJECT

Following the introduction of the neurosurgical microscope, the outcomes in suprasellar meningioma surgery were dramatically improved. More recently, the neurosurgical endoscope has been introduced as a visualization option during removal of skull base tumors, both transcranially and endonasally. The authors retrospectively reviewed the effectiveness of endoscopic endonasal surgery (EES) in the management of suprasellar meningiomas.

METHODS

Between 2002 and 2011, 75 patients (81.3% female) with suprasellar meningiomas underwent EES at the University of Pittsburgh Medical Center. The authors present the results of EES and analyze the resection rates, visual outcome, and complications.

RESULTS

Seventy-one patients presented with primary tumors, whereas 4 were previously treated elsewhere. Their mean age was 57.3 years (range 36-88 years), and most patients presented with visual loss (81.3%). Tumors occupied the tuberculum sellae (86.7%) and planum sphenoidale (50.7%), with extension into the optic canals in 26.7% (unilateral in 21.3% and bilateral in 5.3%) and the pituitary fossa (9.3%). Gross-total tumor resection (Simpson Grade I) was achieved in 76% of the cases in the whole cohort and in 81.4% of the patients in whom it was the goal of surgery. Tumor location and extension into the optic canals was not a limitation for total resection. Tumor size, configuration, and vascular encasement were significant factors that influenced the degree of resection (p < 0.0001). Vision was improved or normalized in 85.7% of the cases. Visual deterioration following EES occurred in 2 patients (3.6%). Complications included postoperative CSF leaks (25.3% overall, 16.1% in recent years) resulting in meningitis in 4 cases. One patient had an intraoperative injury of the artery of Heubner resulting in associated neurological deficit. Another elderly patient died within 1 month after EES due to cerebral vasospasm and multisystem impairment. No patient developed postoperative cerebral contusions, hemorrhage, or seizures. During a mean follow-up period of 29 months (range 1-98 months), 4 patients have shown recurrence, but only 1 required repeat EES.

CONCLUSIONS

With the goal of gross-total tumor resection and visual improvement, EES can achieve very good results, (comparable to microscopic approaches) for the treatment of suprasellar meningiomas. Avoidance of brain and optic nerve retraction, preservation of the vascularization of the optic apparatus, and wide decompression of the optic canals are the main advantages of EES for the treatment of suprasellar meningiomas, while CSF leaks remain a disadvantage.

Technical nuances in the management of tuberculum sellae and diaphragma sellae meningiomas

Object

Tuberculum sellae meningiomas (TSMs) and diaphragma sellae meningiomas (DSMs) are challenging lesions to treat due to their proximity to neurovascular structures.

Methods

The authors reviewed the medical records of patients who underwent surgical excision of TSMs and DSMs from 1990 to 2013. They also describe the technical strategies used to minimize injury to the optic apparatus, vascular structures, and pituitary stalk.

Results

Twenty-four patients with TSM and 6 patients with DSM were included in the study. Seventy percent of the tumors were large (≥ 5 cm). The pterional approach was employed in most cases. Optic canal involvement was observed in 4 patients. Twenty-one patients (70%) had visual dysfunction before surgery. At follow-up (median 18 months), visual improvement was noted in 10 (47.6%) of 21 patients. Gross-total excision was achieved in 22 patients (91.6%) with TSM and 5 (83.3%) with DSM. At last follow-up, 28 patients (93.3%) had a Glasgow Outcome Scale score of 5. There were no deaths in this series.

Conclusions

Tuberculum and diaphragma sellae meningiomas present a unique subset of tumors due to their location. They can be safely excised with minimal morbidity and mortality using microsurgical techniques. Attention to technical details during surgery leads to greater respectability and superior visual outcome.

Endoscopic extended transsphenoidal resection of tuberculum sellae meningiomas: nuances of neurosurgical technique

Over the past decade, advances in endoscopic microsurgical techniques have resulted in an increasingly aggressive endonasal approach to tumors of the midline skull base. Meningiomas of the tuberculum sellae are often closely associated with cerebrovascular structures, and their removal has traditionally required a transcranial approach. An endonasal approach offers many advantages, including early tumor devascularization and tumor debulking (without manipulation of the optic apparatus), direct access to the medial optic canal, and a minimal-access corridor.

Although recent articles have focused on techniques for reaching and approaching the area of the pathology (how to get there), the authors of this report discuss the technical nuances of endoscopic microsurgery when the operator is already “there.” They describe their 6-step technique for endoscopic skull base bone removal, tumor dissection/resection, and closure. They also augment their description with elaborate illustrations.

Case-specific protocol to reduce cerebrospinal fluid leakage after endonasal endoscopic surgery

Object

Endoscopic transsphenoidal surgery is expanding in acceptance, yet postoperative CSF leak rates remain a concern. This study presents the Cornell closure protocol, which has yielded significantly lower postoperative CSF leak rates compared with prior reports, as an algorithm that can be used by centers having difficulty with CSF leak.

Methods

A single closure algorithm for endoscopic surgery has been used since January 2010 at Weill Cornell Medical College. A prospective database noting intraoperative CSF leak, closure technique, and postoperative CSF leak was reviewed. The authors used a MEDLINE search to identify similar studies and compared CSF leak rates to those of patients treated using the Cornell algorithm.

Results

The retrospective study of a prospectively acquired database included 209 consecutive patients. In 84 patients (40%) there was no intraoperative CSF leak and no postoperative CSF leak. In the 125 patients (60%) with an intraoperative CSF leak, 35 of them with high-flow leaks, there were 0 (0%) postoperative CSF leaks.

Conclusions

It is possible to achieve a CSF leak rate of 0% by using this closure protocol. With proper experience, endoscopic skull base surgery should not be considered to have a higher CSF leak rate than open transcranial or microscopic transsphenoidal surgery.

Surgical nuances for nasoseptal flap reconstruction of cranial base defects with high-flow cerebrospinal fluid leaks after endoscopic skull base surgery

Extended endoscopic endonasal approaches have allowed for a minimally invasive solution for removal of a variety of ventral skull base lesions, including intradural tumors. Depending on the location of the pathological entity, various types of surgical corridors are used, such as transcribriform, transplanum transtuberculum, transsellar, transclival, and transodontoid approaches. Often, a large skull base dural defect with a high-flow CSF leak is created after endoscopic skull base surgery. Successful reconstruction of the cranial base defect is paramount to separate the intracranial contents from the paranasal sinus contents and to prevent postoperative CSF leakage. The vascularized pedicled nasoseptal flap (PNSF) has become the workhorse for cranial base reconstruction after endoscopic skull base surgery, dramatically reducing the rate of postoperative CSF leakage since its implementation. In this report, the authors review the surgical technique and describe the operative nuances and lessons learned for successful multilayered PNSF reconstruction of cranial base defects with high-flow CSF leaks created after endoscopic skull base surgery. The authors specifically highlight important surgical pearls that are critical for successful PNSF reconstruction, including target-specific flap design and harvesting, pedicle preservation, preparation of bony defect and graft site to optimize flap adherence, multilayered closure technique, maximization of the reach of the flap, final flap positioning, and proper bolstering and buttressing of the PNSF to prevent flap dehiscence. Using this technique in 93 patients, the authors' overall postoperative CSF leak rate was 3.2%. An illustrative intraoperative video demonstrating the reconstruction technique is also presented.

Endoscopic endonasal surgery for giant pituitary adenomas: advantages and limitations

OBJECT

Giant pituitary adenomas (> 4 cm in maximum diameter) represent a significant surgical challenge. Endoscopic endonasal surgery (EES) has recently been introduced as a treatment option for these tumors. The authors present the results of EES for giant adenomas and analyze the advantages and limitations of this technique.

METHODS

The authors retrospectively reviewed the medical files and imaging studies of 54 patients with giant pituitary adenomas who underwent EES and studied the factors affecting surgical outcome.

RESULTS

Preoperative visual impairment was present in 45 patients (83%) and partial or complete pituitary deficiency in 28 cases (52%), and 7 patients (13%) presented with apoplexy. Near-total resection (> 90%) was achieved in 36 patients (66.7%). Vision was improved or normalized in 36 cases (80%) and worsened in 2 cases due to apoplexy of residual tumor. Significant factors that limited the degree of resection were a multilobular configuration of the adenoma (p = 0.002) and extension to the middle fossa (p = 0.045). Cavernous sinus invasion, tumor size, and intraventricular or posterior fossa extension did not influence the surgical outcome. Complications included apoplexy of residual adenoma (3.7%), permanent diabetes insipidus (9.6%), new pituitary insufficiency (16.7%), and CSF leak (16.7%, which was reduced to 7.4% in recent years). Fourteen patients underwent radiation therapy after EES for residual mass or, in a later stage, for recurrence, and 10 with functional pituitary adenomas received medical treatment. During a mean follow-up of 37.9 months (range 1-114 months), 7 patients were reoperated on for tumor recurrence. Three patients were lost to follow-up.

CONCLUSIONS

Endoscopic endonasal surgery provides effective initial management of giant pituitary adenomas with favorable results compared with traditional microscopic transsphenoidal and transcranial approaches.

Endoscopic endonasal transclival approach to the jugular tubercle

BACKGROUND

The jugular tubercle is a rounded bony prominence that arises from the inferolateral margin of the clivus. In a previous publication, we described the surgical anatomy of the expanded endonasal approach to the jugular tubercle.

OBJECTIVE

To illustrate the translation of laboratory work to the operating room describing the anatomic and technical nuances of the endonasal approach to the jugular tubercle.

METHODS

We review the relevant surgical anatomy needed to perform an endonasal approach to the jugular tubercle, and we select 4 different lesions to illustrate the application of our laboratory findings.

RESULTS

In the first case, exposure and partial drilling of the jugular tubercle was critical to gain an adequate corridor to the meningioma, particularly to its inferolateral margin. This allowed for early devascularization, safe extracapsular dissection, and preservation of surrounding neurovascular structures. In addition, the jugular tubercle was hyperostotic and its resection, along with generous dural removal, provided a grade I Simpson tumor resection. In the second (chondrosarcoma) and third (chordoma) cases, the jugular tubercle was infiltrated by tumor, and consequently its complete resection was essential to achieve total tumor removal. In the last case, an unusual adrenocorticotropic hormone-secreting adenoma recurrence at the jugular tubercle region, the technical modification of the transclival approach presented here was successfully applied to achieve complete resection and Cushing disease remission.

CONCLUSION

The transjugular tubercle variant of the expanded endonasal transclival approach allows for direct access to ventrolateral lesions in the inferior clival/petroclival region with no cerebral or cerebellar retraction, or cranial nerve manipulation during the approach.

A systematic review of published evidence on expanded endoscopic endonasal skull base surgery and the risk of postoperative seizure

Although postoperative seizure is an acknowledged risk following transcranial surgery, the incidence of seizure after removal of intradural pathology via an expanded endoscopic endonasal approach is not well defined. The current study was performed to systematically review the risk of seizure in patients undergoing endoscopic endonasal skull base (EESB) surgery. Embase (1980 to 9 March 2012) and Medline (1950 to 9 March 2012) were searched using a search strategy designed to include any studies that report the perioperative outcomes following EESB surgery. Outcomes of patients undergoing a simple closure of cerebrospinal fluid fistulae or encephaloceles and transellar approaches for pituitary or intrasellar lesions were excluded because this review is focused on large skull base defects. A title search selected those articles relevant to clinical series on expanded endoscopic approaches. A subsequent search of abstracts selected for manuscripts of any report that documented the presence or absence of postoperative seizure. A total of 2234 manuscripts were selected initially and full text analysis produced 67 studies with extractable data regarding the perioperative outcomes for EESB surgery. Of these manuscripts, seven reported the incidence of seizure following EESB procedures. Two of these studies were excluded due to duplication of authorship and institutional data. The overall risk of postoperative seizure following EESB surgery was estimated at 1.1% (six of 530). Subgroup analyses of data revealed that the risk of seizure following an endoscopic endonasal to the anterior cranial base was 2.3% (one patient of 43). For a posterior cranial base approach, the risk of seizure was indeterminate due to deficiency of reporting in the current literature. We concluded that the risk of seizure following an EESB procedure appears to be low (1%). However, the lack of reporting on the incidence of seizures or the use of antiepileptic prophylaxis following EESB procedure is a key limitation. Future EESB studies will need to include seizure as an outcome to accurately define this risk.

Circumferential watertight dural repair using nitinol U-clips in expanded endonasal and sublabial approaches to the cranial base

BACKGROUND

In recent years, significant advances have been made in the field of expanded endonasal approaches that permit treatment of different cranial base intradural lesions.

OBJECTIVE

To report our technique of cranial base dural repair by the application of nitinol U-Clips in endoscope-assisted extended endonasal or sublabial approaches. Closure techniques and postoperative cerebrospinal (CSF) leaks are reported.

METHODS

We reviewed 11 patients with different kinds of cranial base tumors or vascular diseases (2 tuberculum sellae meningiomas, 1 planum sphenoidale meningioma, 4 craniopharyngiomas, 1 recurrent clival chordoma, 1 esthesioneuroblastoma, 1 ethmoidal melanoma metastasis, 1 basilar trunk aneurysm) who underwent an endoscope-assisted extended endonasal or sublabial approach. Dural repair was performed using nitinol U-Clips to circumferentially suture AlloDerm or fascia lata directly to the existing dural borders. Lumbar drainage was not used in 9 patients and was used in 2 patients for 5 days. Patients were evaluated for the appearance of CSF leaks.

RESULTS

Postoperative CSF leak was observed in 1 patient (9%). This required a second transnasal repair.

CONCLUSION

Circumferential dural closure with U-Clips is a useful adjunct to prevent CSF leaks after expanded endonasal or sublabial approaches to the cranial base for treatment of intracranial pathology.

Surgical nuances for removal of olfactory groove meningiomas using the endoscopic endonasal transcribriform approach

Olfactory groove meningiomas represent 10% of intracranial meningiomas and arise in the midline of the anterior cranial fossa along the dura of the cribriform plate and planum sphenoidale. Hyperostosis of the adjacent underlying bone is common, and further extension into ethmoid sinuses and nasal cavity can occur in 15%-25% of cases. Radical tumor resection including the involved dural attachment and underlying hyperostotic bone offers the best chance of a Simpson Grade I resection to minimize recurrence. Incomplete removal of involved hyperostotic bone can result in tumor recurrence at the cribriform plate with extension into the paranasal sinuses. Resection has traditionally been performed using a bifrontal or pterional approach, both of which require some degree of brain retraction or manipulation to expose the tumor. The endoscopic endonasal transcribriform approach offers the most direct and immediate exposure to the tumor without brain retraction and manipulation of neurovascular structures. An endonasal "keyhole craniectomy" is performed in the ventral skull base directly over the basal dural attachment, extending from the posterior wall of the frontal sinus to the planum sphenoidale and tuberculum sellae in the anteroposterior plane, and from one medial orbit to the other in the coronal plane. Excellent panoramic visualization of the keyhole skull base defect can be obtained with a 30° endoscope after performing a modified Lothrop procedure. Because the dural attachment is adjacent to the paranasal sinuses, early devascularization and total Simpson Grade I removal of the tumor including the dural attachment and underlying hyperostotic bone can be achieved in properly selected patients. This approach is also very suitable for meningiomas that have recurred or extended into the paranasal sinuses. Extracapsular, extraarachnoid dissection of the tumor from the frontal lobes and neurovascular structures can be performed using conventional bimanual microsurgical techniques. In this report, we review the surgical technique and describe our operative nuances for removal of olfactory groove meningiomas, including recurrent tumors with extension into the nasal cavity, using a purely endoscopic endonasal transcribriform approach. In addition, we discuss the advantages, limitations, patient selection, and complications of this approach. We specifically highlight our technique for multilayer reconstruction of large anterior skull base dural defects using fascia lata and acellular dermal allograft supplemented by bilateral vascularized pedicled nasoseptal flaps. Three new cases of endoscopically resected olfactory groove meningiomas are also presented.

Surgical decision-making strategies in tuberculum sellae meningioma resection

OBJECT

Although the transcranial route (TCR) has been the traditional approach for removing tuberculum sellae meningiomas (TSMs), the use of the microscopic and/or more recently the endoscopic transsphenoidal approach (ETSA) has gained acceptance for selected cases. In this study, the authors present their experience with the ETSA and the TCR and examine the criteria most important for deciding the optimal approach in a particular case.

METHODS

The authors retrospectively reviewed recent cases of TSMs treated surgically by the senior author via either the TCR or the ETSA or both. Demographic information, clinical presentation, and clinical and radiological outcomes of the patients were evaluated.

RESULTS

Twenty-seven patients underwent removal of a TSM during a recent period. Gross-total or near-total resection was achieved in 20 (91%) of 22 patients who underwent resection via the TCR and in 3 (60%) of 5 patients who underwent the ETSA. Among the patients in whom gross- or near-total resection was achieved, recurrence was observed in only 1 patient, whose tumor was removed via the ETSA.

CONCLUSIONS

In the majority of patients, the TCR provided complete resection of the tumor without compromising the safety of the procedure. In select cases of tumors with a reasonable size and location (midline and/or extending into the sphenoid sinus) as well as no involvement of inaccessible neurovascular and bony elements via this approach, the ETSA could also be a viable option.

Expanded endonasal endoscopic resection of anterior fossa meningiomas: report of 13 cases and meta-analysis of the literature

Object

Transnasal endoscopic (TNE) approaches have been proposed for the resection of anterior cranial base meningiomas. The purpose of this article was to evaluate the results of endoscopic resection of anterior cranial fossa meningiomas by reviewing available published data in addition to the authors' experience with 13 cases.

Methods

The literature was searched via OVID to identify all available disaggregate data pertaining to anterior fossa meningiomas treated primarily by TNE. In addition, the authors reviewed the records of a personal series of 13 patients who underwent TNE removal of parasellar meningiomas through a pure TNE approach.

Results

Meta-analysis from studies included a total of 69 patients with adequate disaggregated data to summarize. Mean age (± SD) at surgery was 53.3 ± 13.0 years (range 27–80 years); 78% of the patients were women. Tumor size was skewed toward smaller lesions, with a mean volume of 24.4 ± 2.9 cm3. Intraoperative impressions were of gross-total resection in 76% of cases. The most common complication reported was CSF leakage, occurring in 32% of the cases (22 of 69). The rate of CSF leakage was not affected by size (p = 0.52), location of tumor (p = 0.9), or age (p = 0.56). There was 1 death overall. The mean duration of follow-up was 21 ± 18 months.

Conclusions

Transnasal endoscopic resection of anterior cranial base meningiomas is feasible in selected cases. Reported resection rates are adequate, although the follow-up in the reported series is too short (mean 21 months) to make definitive conclusions regarding the long-term effectiveness. Cerebrospinal fluid leakage is a common complication, although it appears not to be associated with additional morbidity except for the need for reoperation. Long-term results are necessary before considering TNE resection as a valid alternative, in selected cases, to the more established transcranial techniques.

Surgical nuances for removal of tuberculum sellae meningiomas with optic canal involvement using the endoscopic endonasal extended transsphenoidal transplanum transtuberculum approach

Tuberculum sellae meningiomas frequently extend into the optic canals. Radical tumor resection including the involved dural attachment, underlying hyperostotic bone, and intracanalicular tumor in the optic canal offers the best chance of a Simpson Grade I resection to minimize recurrence. Decompression of the optic canal with removal of the intracanalicular tumor also improves visual outcome since this portion of the tumor is usually the cause of asymmetrical visual loss.

The purely endoscopic endonasal extended transsphenoidal approach offers a direct midline trajectory and immediate access to tuberculum sellae meningiomas without brain retraction and manipulation of neurovascular structures. Although the endoscopic approach has been previously criticized for its inability to remove tumor within the optic canals, complete Simpson Grade I tumor removal including intracanalicular tumor, dural attachment, and involved hyperostotic bone can be achieved in properly selected patients. Excellent visualization of the suprasellar region and the inferomedial aspects of both optic canals allows for extracapsular, extraarachnoid dissection of the tumor from the critical structures using bimanual microsurgical dissection.

In this report, the authors describe the operative nuances for removal of tuberculum sellae meningiomas with optic canal involvement using a purely endoscopic endonasal extended transsphenoidal (transplanum transtuberculum) approach. They specifically highlight the technique for endonasal bilateral optic nerve decompression and removal of intracanalicular tumor to improve postoperative visual function, as demonstrated in 2 illustrative cases. Special attention is also given to cranial base reconstruction to prevent CSF leakage using the vascularized pedicled nasoseptal flap.

Optic canal involvement in tuberculum sellae meningiomas: influence on approach, recurrence, and visual recovery

BACKGROUND

Tuberculum sellae meningiomas frequently extend into the optic canals.

OBJECTIVE

To emphasize the high frequency of optic canal (OC) involvement in tuberculum sellae meningiomas; the importance of opening the OC and of removing tumor within the canal; and the effect of this maneuver on visual outcome, recurrence rates, and surgical approach selection.

METHODS

A retrospective review of 58 patients with tuberculum sellae meningiomas treated surgically by the senior author (O.A.M) between 1993 and 2009 was performed. The frequency of involvement of the OC was documented, as well as the impact of removal of this part of the tumor on visual outcome and recurrence.

RESULTS

Total resection (Simpson grade 1) was achieved in 51 of 58 patients (87.9%). The tumor invaded the optic canal in 67%. Tumor resection from the optic nerve was achieved in all cases, and most (92%) underwent deroofing of the OC for this purpose. The dura over the tuberculum sella and/or planum sphenoidale was removed in all patients. Eighty-three percent required removal of affected hyperostotic bone. Vision was improved and/or spared in 88%. The average follow-up period was 23 months with 1 recurrence detected.

CONCLUSION

In the majority of cases, tuberculum sellae meningiomas extend into 1 or both OCs. Opening the OC for resection of the intracanalicular portion of the tumor enabled us to achieve excellent visual outcome. The supraorbital craniotomy remains the favored approach for removal of such tumors because it allows unroofing of both OCs, wide excision of the dura, and drilling of the affected bone.

Endoscopic endonasal transethmoidal transcribriform transfovea ethmoidalis approach to the anterior cranial fossa and skull base

OBJECTIVE

The anterior skull base, in front of the sphenoid sinus, can be approached using a variety of techniques including extended subfrontal, transfacial, and craniofacial approaches. These methods include risks of brain retraction, contusion, cerebrospinal fluid leak, meningitis, and cosmetic deformity. An alternate and more direct approach is the endonasal, transethmoidal, transcribriform, transfovea ethmoidalis approach.

METHODS

An endoscopic, endonasal approach was used to treat a variety of conditions of the anterior skull base arising in front of the sphenoid sinus and between the orbits in a series of 44 patients. A prospective database was used to detail the corridor of approach, closure technique, use of intraoperative lumbar drainage, operative time, and postoperative complications. Extent of resection was determined by a radiologist using volumetric analysis.

RESULTS

Pathology included meningo/encephaloceles (19), benign tumors (14), malignant tumors (9), and infectious lesions (2). Lumbar drains were placed intraoperatively in 20 patients. The CSF leak rate was 6.8% for the whole series and 9% for intradural cases. Leaks were effectively managed with lumbar drainage. Early reoperation for cerebrospinal fluid (CSF) leak occurred in 1 patient (2.2%). There were no intracranial infections. Greater than 98% resection was achieved in 12 of 14 benign and 5 of 9 malignant tumors.

CONCLUSION

The endoscopic, endonasal, transethmoidal, transcribriform, transfovea ethmoidalis approach is versatile and suitable for managing a variety of pathological entities. This minimal access surgery is a feasible alternative to transcranial, transfacial, or combined craniofacial approaches to the anterior skull base and anterior cranial fossa in front of the sphenoid sinus. The risk of CSF leak and infection are reasonably low and decrease with experience. Longer follow-up and larger series of patients will be required to validate the long-term efficacy of this minimally invasive approach.