The endoscopic extended transsphenoidal approach for craniopharyngiomas

The role of endoscopic endonasal salvage surgery in recurrent or residual craniopharyngioma after a transcranial approach: a systematic review

BACKGROUND

The management of craniopharyngiomas is challenging due to their high rate of recurrence following resection. Excision of recurrent tumors poses further surgical challenges due to loss of arachnoidal planes and adherence to anatomical structures. The endoscopic endonasal approach (EEA) offers a favorable alternative to transcranial approaches for primary craniopharyngiomas. However, the safety and efficacy of EEA for recurrent tumors, specifically after a prior transcranial approach, needs further investigation.

METHODS

We performed a systematic review using PubMed to develop a database of cases of recurrent craniopharyngiomas previously treated with a transcranial approach.

RESULTS

Fifteen articles were included in this review with a total of 75 cases. There were 50 males and 25 females with a mean age of 38 years (range 2-80). One prior transcranial surgery was done in 80.0% of cases, while 8.0% had two and 12.0% had more than two prior surgeries. Radiotherapy after transcranial resection was given in 18 cases (24.0%). Following EEA, vision improved in 60.0% of cases, and vision worsened in 8.6% of the cases. Of cases, 64.4% had pre-existing anterior hypopituitarism, and 43.8% had diabetes insipidus prior to EEA. New anterior hypopituitarism and diabetes insipidus developed in 24.6% and 21.9% of cases, respectively following EEA. Gross total resection (GTR) was achieved in 64.0%, subtotal resection in 32.0%, and partial resection in 4.0% revision EEA cases. GTR rate was higher in cases with no prior radiotherapy compared to cases with prior radiotherapy (72.0% vs 39.0%, p = 0.0372). The recurrence rate was 17.5% overall but was significantly lower at 10.0% following GTR (p = 0.0019). The average follow-up length was 41.2 months (range, 1-182 months).

CONCLUSION

The EEA can be utilized for resection of recurrent or residual craniopharyngiomas previously managed by a transcranial approach.

Endoscopic trans-sphenoidal pituitary surgery does not impact postoperative nasal quality of life

PURPOSE

The aim of this prospective longitudinal study was to assess both subjective quality of life using questionnaires and objective examination of nasal function with regard to olfaction, nasal air flow and mucociliary clearance in patients after minimally invasive, turbinate-preserving endoscopic transnasal trans-sphenoidal pituitary surgery.

METHODS

Patients undergoing endoscopic transnasal pituitary surgery were recruited prospectively and examined during three study visits, preoperatively and 3 and 6 months postoperatively. We examined nasal function using sniffin' sticks test, rhinomanometry, saccharin transit time test, and endoscopic and radiological scores. In addition, the influence on subjective quality of life and mental health was recorded using the Sinonasal-Outcome-Test-20 (SNOT-20) and the Hospital-Anxiety-and-Depression-Scale (HADS).

RESULTS

20 patients undergoing endoscopic pituitary tumor resections were included. No significant changes in olfaction or mucociliary clearance were noted. Nasal air flow showed a tendency to increase in the postoperative course lacking significance. Both the endoscopy and the radiological scores showed a significant deterioration, especially after 3 months, with a trend towards improvement over time. However, neither the SNOT-20 nor the HADS showed significant changes compared to baseline.

CONCLUSIONS

Our concept of minimally invasive endoscopic tumor resections on the pituitary gland with preservation of nasal turbinates shows low morbidity for the patient. Despite objectifiable surgery-associated changes in the nose, nasal physiology in terms of smell, airflow and mucociliary clearance can be preserved and the subjective quality of life of our patients remains stable.

Craniopharyngioma in Pediatrics and Adults

Craniopharyngiomas are rare malignancies of dysembryogenic origin, involving the sellar and parasellar areas. These low-grade, epithelial tumors account for two main histological patterns (adamantinomatous craniopharyngioma and papillary craniopharyngioma), which differ in epidemiology, pathogenesis, and histomorphological appearance. Adamantinomatous craniopharyngiomas typically show a bimodal age distribution (5-15 years and 45-60 years), while papillary craniopharyngiomas are limited to adult patients, especially in the fifth and sixth decades of life. Recently, craniopharyngioma histological subtypes have been demonstrated to harbor distinct biomolecular signatures. Somatic mutations in CTNNB1 gene encoding β-catenin have been exclusively detected in adamantinomatous craniopharyngiomas, which predominantly manifest as cystic lesions, while papillary craniopharyngiomas are driven by BRAF V600E mutations in up to 95% of cases and are typically solid masses. Despite the benign histological nature (grade I according to the World Health Organization classification), craniopharyngiomas may heavily affect long-term survival and quality of life, due to their growth pattern in a critical region for the presence of eloquent neurovascular structures and possible neurological sequelae following their treatment. Clinical manifestations are mostly related to the involvement of hypothalamic-pituitary axis, optic pathways, ventricular system, and major blood vessels of the circle of Willis. Symptoms and signs referable to intracranial hypertension, visual disturbance, and endocrine deficiencies should promptly raise the clinical suspicion for sellar and suprasellar pathologies, advocating further neuroimaging investigations, especially brain MRI. The optimal therapeutic management of craniopharyngiomas is still a matter of debate. Over the last decades, the surgical strategy for craniopharyngiomas, especially in younger patients, has shifted from the aggressive attempt of radical resection to a more conservative and individualized approach via a planned subtotal resection followed by adjuvant radiotherapy, aimed at preserving functional outcomes and minimizing surgery-related morbidity. Whenever gross total removal is not safely feasible, adjuvant radiotherapy (RT) and stereotactic radiosurgery (SRS) have gained an increasingly important role to manage tumor residual or recurrence. The role of intracavitary therapies, including antineoplastic drugs or sealed radioactive sources, is predominantly limited to monocystic craniopharyngiomas as secondary therapeutic option. Novel findings in genetic profiling of craniopharyngiomas have unfold new scenarios in the development of targeted therapies based on brand-new biomolecular markers, advancing the hypothesis of introducing neoadjuvant chemotherapy regimens in order to reduce tumor burden prior to resection. Indeed, the rarity of these neoplasms requires a multispecialty approach involving an expert team of endocrinologists, neurosurgeons, neuro-ophthalmologists, neuroradiologists, radiotherapists, and neuro-oncologists, in order to pursue a significant impact on postoperative outcomes and long-term prognosis.

Comparison of Graft Materials in Multilayer Reconstruction with Nasoseptal Flap for High-Flow CSF Leak during Endoscopic Skull Base Surgery

Cerebrospinal fluid (CSF) leak is a crucial complication after endoscopic skull base surgery. Therefore, multilayer reconstruction with grafts is as essential as a reconstruction with pedicled flaps. Although widely used, the multilayer technique with autologous fascia lata has drawbacks, such as additional wound and donor site complications. We compared acellular dermal graft and banked homologous fascia lata graft (alternative grafts) with autologous fascia lata graft for high-flow CSF leak repair. We retrospectively enrolled 193 subjects who underwent endoscopic skull base reconstruction with multilayer fascial grafts and nasoseptal flap for high-flow CSF leaks from November 2014 to February 2020 at a single institution. Acellular dermal matrix (ADM), banked homologous fascia lata, and autologous fascia lata were used in 48 (24.9%), 102 (52.8%), and 43 (22.3%) patients, respectively. Postoperative CSF leaks occurred in 23 (11.9%) patients and meningitis in 8 (4.1%). There was no significant difference in postoperative CSF leak (p = 0.36) and meningitis (p = 0.17) across the graft groups. Additionally, we could not find out contributing risk factors for postoperative CSF leak and meningitis. ADM and banked homologous fascia lata are non-inferior to autologous fascia lata for endoscopic skull base reconstruction in water-tight reconstruction or safety without additional donor site morbidities.

Feasibility of endoscopic endonasal resection of intrinsic third ventricular craniopharyngioma in adults

Intrinsic third ventricular craniopharyngiomas (IVCs) are usually considered as a contraindication of endoscopic endonasal approach (EEA). The aim of this study is to evaluate the safety and feasibility of EEA for the resection of IVCs based on MRI topographical diagnosis and surgical findings. We reviewed the data of 22 patients who were diagnosed to be IVCs according to five MRI criteria and underwent surgery through EEA. Sixteen IVCs were resected using endoscopic endonasal infrachiasmatic corridor, five IVCs by using endoscopic endonasal suprachiasmatic trans-lamina terminalis corridor, and one IVC by using both the infrachiasmatic and suprachiasmatic corridors. During the operation, all the 22 cases were verified to be IVCs. Gross total resection was achieved in 21 (95.5%) patients. After surgery, visual improvement was observed in 14 (63.6%) patients, no change in 6 (27.3%) patients, and some deterioration in 2 (9.1%) patients. An improvement in intellectual ability was observed in nine (40.9%) patients, no change in twelve (54.5%) patients, and some deterioration in one (4.5%) patient. Fifteen of the 22 patients (68.2%) developed new endocrinological deficit. One postoperative cerebral spinal fluid leakage occurred. EEA can be used as a safe and efficacious approach for the radical resection of IVCs. The combination of the five MRI criteria may serve as an accurate preoperative diagnostic tool to define the topographical relationships between craniopharyngiomas and the third ventricle. The endoscopic transnasal view from below has the advantage of clarifying the relationship between tumors and the third ventricle floor.

Endoscopic Endonasal Transsphenoidal Surgery for Recurrent Craniopharyngiomas

Object

Although revision surgery for recurrent craniopharyngiomas is more challenging than primary surgery and often accompanies a higher risk of death and complications, endoscopic endonasal transsphenoidal surgery (EETS) is sometimes still an effective and reliable treatment option. In this study, we introduced the surgical outcomes of EETS for recurrent craniopharyngiomas and summarized the surgical experiences.

Methods

Between 2014 and 2018, 28 patients with recurrent craniopharyngiomas underwent 29 EETS in our department. We regarded the patient undergoing two EETS as two independent patients in statistical analysis. Of the 29 patients, 16 had undergone 1 previous surgery, 10 had undergone 2 previous surgeries, and the remaining 3 patients had undergone 3 surgeries. The extent of resection, visual and endocrine outcomes, and complications of all the patients were collected and analyzed.

Results

Gross total resection was accomplished in 16 patients (55.17%), subtotal resection in 11 patients (37.93%), and partial resection in 2 patients (6.9%). Among the 22 patients with preoperative visual acuity and visual field impairment, some degree of vision improvement was observed in 18 patients, 3 patients were without visual change, and perpetual deterioration of vision occurred in one patient. The remaining six patients had normal vision before and after surgery. Postoperative endocrine tests showed that, among five patients with normal preoperative pituitary hormone function, only one patient still had normal pituitary hormone function and the other four patients had one or more hypothalamic-pituitary axes involved. None of the patients with preoperative endocrine dysfunction had endocrine function improved. Diabetes insipidus was observed in six new cases postoperatively. Cerebrospinal fluid (CSF) leakage occurred in 1 patient. One patient had bacterial meningitis, which was cured with antibiotics and a lumbar drain. No serious morbidity and mortality occurred in all patients.

Conclusions

For recurrent craniopharyngiomas, a personalized treatment plan should be developed according to the tumor characteristics and the patient's situation. There is no omnipotent method to be used for all patients. The EETS still is a safe and effective way to treat recurrent craniopharyngiomas in appropriate patients.

The eagle sign: a new preoperative MRI-based tool for predicting topographic correlation between craniopharyngioma and hypothalamus

PURPOSE

Accurate prediction of topographical correlation between craniopharyngiomas (CPs) and hypothalamus is important for treatment. This study sought to develop a predicting tool based on preoperative-MRI through radiological-surgical-pathological-outcome analysis.

MATERIALS AND METHODS

Third ventricle floor (TVF), mammillary bodies and cerebral peduncle were evaluated through preoperative-MRI. An eagle-head-like sign named "eagle sign" was observed. Normal TVF on sagittal-MRI was defined as the baseline. Variants of the sign were analyzed by comparing with the baseline and corresponding correlations of CPs with hypothalamus were verified using intraoperative records, histopathology and outcome evaluation.

RESULTS

A total of 146 CPs patients, who undergone endoscopic endonasal procedure were divided into four groups based on the variants of "eagle sign". Group A: 24 patients with the upward sign; group B: 81 with the downward sign; group C: 21 with the anterior TVF upward sign and group D: 20 with the unidentifiable sign. Surgical-pathological analysis showed significant correlations between 95.8% CPs in group A and 95.2% in group C with tumor topography and tumor adherence to the hypothalamus. These CPs had their origins beneath the hypothalamus. In contrast, groups B and D, with hypothalamic origin, showed hypothalamic infiltration by tumor in 97.5% and 95% of cases in groups B and D, respectively. Outcomes of groups A and C were relatively better than groups B and D. Predictive sensitivity and specificity of "eagle sign" were more than 90%.

CONCLUSION

"Eagle sign" is an accurate tool for predicting topographic correlations between CPs and hypothalamus with high sensitivity and specificity.

Endoscopic transsphenoidal surgery for resection of pituitary macroadenoma: A retrospective study

BACKGROUND

The endoscopic transsphenoidal approach is an efficient minimally invasive procedure for removal of pituitary tumors that can be accomplished through a one-hand or two-hand approach. The one-hand procedure through one nostril is more intuitive for surgeons, but maneuvering the instruments can be restrictive. The two-hand procedure using a one-and-half nostril approach provides more precise manipulation. This study aimed to compare the surgical outcomes of one-hand/mono-nostril and two-hand/one-and-half nostril surgeries for resection of large pituitary tumors by a single neurosurgeon.

MATERIALS AND METHODS

The surgical data of 78 consecutive cases with pituitary macroadenoma (diameter >1 cm) were reviewed retrospectively. Altogether, 30 cases received one-hand/mono-nostril surgery, while 48 cases received two-hand/one-and-half nostril surgery. Postoperative outcomes of the two operations were compared.

RESULTS

The operative time, hospital stay, residual rate of pituitary macroadenoma, visual field, surgical complications, and re-operative rates were slightly improved in the two-hand/one-and-half nostril surgery group compared with that in the one-hand/mono-nostril surgery group (all p>0.05). However, postoperative hypopituitarism was less frequent (1/48; 2.0%) with the two-hand/one-and-half nostril approach than with the mono-nostril approach (p = 0.004). Similar surgical outcomes were found in all patients with either small or large pituitary tumors, except that the difference in postoperative improvement in visual field change reached statistical significance (p = 0.044).

CONCLUSION

A single-surgeon endoscopic endonasal transsphenoidal surgery with two-hand/one-and-half nostril approach is an effective and safe procedure for removal of large pituitary tumors.

Preservation of nasal turbinates in endoscopic, anterior skull base surgery-yes, we can!

Objective

To evaluate the frequency, type and indications of nasal turbinate (NT) resection during endoscopic, anterior skull base surgery and to analyze factors that may have an impact on the need of NT removal.

Methods

In this retrospective cohort study, 306 subjects (150 males and 156 females, mean age 55.4 ± 15.3 years) who underwent multidisciplinary, transnasal, endoscopic tumor surgery of the anterior skull base using 4-handed techniques between 2011 and 2019 at the Department of Otorhinolaryngology, Medical University of Graz, were included.

Results

In the majority of interventions (n = 281/306; 91.8%), all NT were preserved. Significant factors influencing the need of NT resections turned out to be type of endoscopic approach (p < 0.001; V = 0.304), sagittal (p = 0.003; d = 0.481) and transversal (p = 0.017; d = 0.533) tumor diameter, tumor type (p < 0.001; V = 0.355) and tumor location (p < 0.001; V = 0.324).

Conclusions

NT can be preserved in the majority of patients undergoing tumor resection in anterior, transnasal, skullbase surgery and routine resection of NT should be avoided. Variables that have an impact on the need of NT resections are types of endoscopic approaches, sagittal and transversal tumor extension and tumor type. These factors should be considered in planning of surgery and preoperative information of patients.

Predicting post-operative cerebrospinal fluid (CSF) leak following endoscopic transnasal pituitary and anterior skull base surgery: a multivariate analysis

BACKGROUND

Post-operative CSF leak is the major source of morbidity following endoscopic transsphenoidal surgery. The purpose of this study was to identify factors associated with post-operative CSF leak in patients undergoing this surgery and facilitate the prospective identification of patients at higher risk of this complication.

METHODS

A review of a prospectively maintained database containing details of 270 endoscopic transsphenoidal operations performed by the senior author over a 9-year period was performed. Univariate analysis was performed using the Chi-squared and Fisher's exact tests, as appropriate. A logistic regression model was constructed for multivariate analysis.

RESULTS

The rate of post-operative CSF leak in this series was 9%. On univariate analysis, previous surgery, resection of craniopharyngiomas, adenomas causing Cushing's disease and intra-operative CSF leaks were associated with an increased risk of post-operative CSF leak. The use of a vascularised nasoseptal flap and increasing surgical experience were associated with a decreased rate of CSF leak. On multivariate analysis, a resection of tumour for Cushing's disease (OR 5.79, 95% CI 1.53-21.95, p = 0.01) and an intra-operative CSF leak (OR 4.56, 95% CI 1.56-13.32, p = 0.006) were associated with an increased risk of post-operative CSF leak. Increasing surgical experience (OR 0.14, 95% CI 0.04-0.46, p = 0.001) was strongly associated with a decreased risk of post-operative CSF leak.

CONCLUSIONS

Increasing surgical experience is a strong predictor of a decreased risk of developing post-operative CSF leak following endoscopic transsphenoidal surgery. Patients with Cushing's disease and those who develop an intra-operative CSF leak should be managed with meticulous skull base repair and close observation for signs of CSF leak post-operatively.

Acellular dermal matrix as an alternative to autologous fascia lata for skull base repair following extended endoscopic endonasal approaches

BACKGROUND

Skull base reconstruction after extended endoscopic endonasal approaches (EEAs) can be challenging. In addition to the nasoseptal flap, which has been adopted by most centers, autologous fascia lata is also often utilized. Harvesting of fascia lata requires a separate thigh incision, may prolong recovery, and results in a visible scar. In principal, the use of non-autologous materials would be preferable to avoid a second incision and maintain the minimally invasive nature of the approach, assuming the CSF leak rate is not compromised.

OBJECTIVE

To assess the efficacy of acellular dermal matrix (ADM) as a non-autologous alternative to autologous fascia lata graft for watertight closure of the cranial base following EEAs.

METHODS

A retrospective chart review of extended EEAs performed before and after the transition from fascia lata to ADM was performed. Cases were frequency matched for approach, pathology, BMI, use of lumbar drainage, and tumor volume. Power analysis was performed to estimate the sample size needed to demonstrate non-inferiority.

RESULTS

ADM was used for watertight closure of the cranial base in 19 consecutive extended endoscopic endonasal approaches (16 gasket-seals and 3 buttons) with 1 postoperative CSF leak at the last follow-up (median 5.3, range 1.0-12.6 months). All patients had high-flow intraoperative leaks. The cohort included 8 meningiomas, 8 craniopharyngiomas, 2 chordomas, and 1 pituicytoma ranging in size from 0.2 to 37.2cm³ (median 5.5, IQR 2.8-13.3 cm³). In 19 historical controls who received fascia lata, there were 2 postoperative CSF leaks.

CONCLUSIONS

Preliminary results suggest that ADM provides a non-inferior non-autologous alternative to fascia lata for watertight gasket-seal and button closures following extended EEAs, potentially reducing or eliminating the need to harvest autologous tissue.

The endoscopic endonasal approach for pediatric craniopharyngiomas: the key lessons learned

PURPOSE

The aim of this study is to highlight the role of the endoscopic endonasal approach (EEA) in pediatric craniopharyngiomas by reviewing our experience and the key lessons learned from the application of this approach in children.

METHODS

Between 1998 and 2017, 12 pediatric craniopharyngiomas were treated via EEA at our institution. Demographic data, preoperative assessment, tumor features, surgical results, complications, and recurrences were analyzed.

RESULTS

Visual defects were the most frequent presenting sign. Seven craniopharyngiomas were infradiaphragmatic, and five were supradiaphragmatic. The EEA was successfully performed in all cases with no complication related to children's sinonasal anatomy. Gross total resection (GTR) rate was of 75%. Endocrinological disturbances improved in one case (20%) and worsened in three (60%). New onset of diabetes insipidus was observed in four (36%) children. Visual defect improved in 91% of cases, with no new postoperative deficit. Postoperative cerebrospinal fluid (CSF) leak occurred in one patient (8%). Three patients (27%) experienced tumor regrowth, and one craniopharyngioma recurred (mean follow-up, 78 months).

CONCLUSIONS

The EEA offers a straight route to the sellar-suprasellar, making it the ideal approach for pediatric infradiaphragmatic craniopharyngiomas. In supradiaphragmatic craniopharyngiomas, the extended EEA provides a clearer and close-up visualization of the tumor-hypothalamus interface, which can grant better results in terms of quality of life. The pediatric skull base anatomy should not represent a contraindication for the endoscopic technique. Larger series encompassing a wider spectrum of pediatric craniopharyngiomas are needed to further support the benefits of this surgical approach.

Outcomes following endoscopic endonasal resection of sellar and supresellar lesions in pediatric patients

PURPOSE

The endoscopic endonasal approach (EEA) is a credible surgical alternative for the resection of sellar and suprasellar lesions such as pituitary adenomas, craniopharyngiomas, and Rathke cleft cysts. However, its application to pediatric patients poses several unique challenges that have not yet been well evaluated. The authors evaluate the safety, efficacy, and outcomes associated with the use of the EEA for treatment of these pathologic entities in pediatric patients.

METHODS

Retrospective review of 30 patients between the ages of two and 24 who underwent endoscopic endonasal resection of sellar or suprasellar lesions between January 2010 and December 2015. Endocrinological and ophthalmological outcomes, as well as extent of resection and complications were all evaluated.

RESULTS

Gross total resection was achieved in eight of the nine pituitary adenomas, nine of the 12 craniopharyngiomas, and six of the nine Rathke cleft cysts. Of the 30 patients, 22 remained disease free at last follow-up. A total of six patients developed hypopituitarism and five developed diabetes insipidus. Eleven patients experienced improved vision, sixteen experienced no change, and one patient experienced visual worsening. Postoperative cerebrospinal fluid leak was seen in a single case and later resolved, vasospasm/stroke was experienced by 10% of patients, and new obesity was recorded in 10% of patients. There were no perioperative deaths.

CONCLUSIONS

Endoscopic endonasal resection is a safe and effective surgical alternative for the management of sellar and suprasellar pathologies in pediatric populations with excellent outcomes, minimal complications, and a low risk of morbidity.

Endoscopic transsphenoidal approach to skull base lesions. A clinical prospective study

OBJECTIVE

To review the patients operated by endoscopic transphenoidal approach for skull base lesions. All the clinical data including age, gender, type of pathology, surgical outcome and surgical complications were studied.

METHODS

A clinical prospective study was conducted on 94 cases with skull base lesion that were treated in Neuroscience Hospital in Baghdad, Iraq between October 2011 and December 2016. We followed each patient for an average of 2 years after surgery to determine most common lesion involving the skull base, age and gender distribution, surgical outcome, complications and hospital accommodation. Freeze system of Storz all the cases in the study.

RESULTS

The majority of our patients were between the ages of 20-29 years. Among the 94 patients, 67% had macro adenomas, followed by craniopharyngioma 11%. The mortality rate was 2.1%, Gross total removal was 57.4%. All patients show improvement of the headache after surgery, visual improvement was noticed in 73.4% and hospital accommodation was 2-5 days. Three patients developed cerebrospinal fluid leak, Infection meningitis developed in 3 patients 3.1%, and 2 patients (2.1%) suffered from hormonal disorders and were referred to endocrinologist for therapy. Diabetes insipidus developed as a temporary complication in 4 cases (4.2%).

CONCLUSION

Trassphenoidal surgery is relatively safe surgery for properly selected patients.

Anterior communicating artery division in the endoscopic endonasal translamina terminalis approach to the third ventricle: an anatomical feasibility study

BACKGROUND

Endonasal endoscopic approaches (EEA) to the third ventricle are well described but generally use an infrachiasmatic route since the suprachiasmatic translamina terminalis corridor is blocked by the anterior communicating artery (AComA). The bifrontal basal interhemispheric translamina terminalis approach has been facilitated with transection of the AComA. The aim of the study is to describe the anatomical feasibility and limitations of the EEA translamina terminalis approach to the third ventricle augmented with AComA surgical ligation.

METHODS

Endoscopic dissections were performed on five cadaveric heads injected with colored latex using rod lens endoscopes attached to a high-definition camera and a digital video recorder system. A stepwise anatomical dissection of the endoscopic endonasal transtuberculum, transplanum, translamina terminalis approach to the third ventricle was performed. Measurements were performed before and after AComA elevation and transection using a millimeter flexible caliper.

RESULTS

Multiple comparison statistical analysis revealed a statistically significant difference in vertical exposure between the control condition and after AComA elevation, between the control condition and after AComA division and between the AComA elevation and division (p < 0.05). The mean difference in exposed surgical area was statistically significant between the control and after AComA division and between elevation and AComA division (p < 0.01), whereas it was not statistically significant between the control condition and AComA elevation (NS).

CONCLUSION

The anatomical feasibility of clipping and dividing the AComA through an EEA has been demonstrated in all the cadaveric specimens. The approach facilitates exposure of the suprachiasmatic optic recess within the third ventricle that may be a blind spot during an infrachiasmatic approach.

Impact of Multilayer Vascularized Reconstruction after Skull Base Endoscopic Endonasal Approaches

Background  The use of vascularized flap to reconstruct the skull base defects has dramatically changed the postoperative cerebrospinal fluid (CSF) leak rates allowing the expansion of endoscopic skull base procedures. At present, there is insufficient scientific evidence to permit identification of the optimal reconstruction technique after the endoscopic endonasal approach (EEA). Objective  The main purpose of this article is to establish the risk factors for failure in the reconstruction after EEA and whether the use of a surgical reconstruction protocol can improve the surgical results. Material and Methods  A retrospective cohort study was conducted in our institution, selecting patients that underwent EEA with intraoperative CSF leak. Two reconstructive protocols were defined based on different reconstructive techniques; both were vascularized but one monolayer and the other multilayer. A multivariate analysis was performed with outcome variable presentation of postoperative leak. Results  One hundred one patients were included in the study. Patients reconstructed with protocol 1, with the diagnosis different to the pituitary adenoma and older than 45 years old had higher risk of presenting postoperative leak, and with statistically significant differences when we adjusted for the remaining variables. Conclusion  The vascularized reconstructions after endoscopic endonasal skull base approaches have demonstrated to be able to obtain a low rate of postoperative CSF leak. The multilayer vascularized technique may provide a more evolved technique, even reducing the postoperative leak rates comparing with the monolayer vascularized one. The reconstructive protocol employed in each case, as well as age and histological diagnosis, is independent risk factor for presenting postoperative leak.

A novel endoscopic classification for craniopharyngioma based on its origin

Endoscopic endonasal approach for craniopharyngioma (CP) resection provides a wide view and direct observation of hypothalamus and origin of tumor. Under endoscopy, 92 CPs were classified into 2 types: Peripheral and Central, according to its relation to pituitary stalk. Peripheral type was further divided into 3 subtypes: Hypothalamic stalk, Suprasellar stalk and Intrasellar stalk CP, according to the different origin site along hypothalamus-pituitary axis. Peripheral type arisen from the stalk but expanded and grown laterally in an exophytic pattern, accounting for 71.7% of all CPs, preservation rate of stalk was higher (76.0%). Central type grew within and along pituitary stalk and located strictly in the midline. The pituitary stalk was hardly preserved (only15.4%). Hypothalamic stalk CPs (n = 36, 54.6%) developed from the junction of hypothalamus and stalk, hypothalamus damage was found in all of this subtype after surgery. Suprasellar stalk CPs (n = 14, 21.2%) originated from the lower portion of stalk and displaced hypothalamus upward rather than infiltrated it. Intrasellar stalk CPs (n = 16, 24.2%) arose from the subdiaphragma portion of the stalk, with less hypothalamus damage. Recoginzing the origin of CP is helpful to understand its growth pattern and relation to hypothalamus, which is critical in planning the most appropriate surgical approach and degree of excision.

Endoscopic transnasal surgery of clival lesions: our experience

BACKGROUND

The clivus is a region characterized by complex anatomy, with vascular and neural structures that are located in close proximity. Different pathologies can affect this area, and traditional surgical approaches were open approaches. Recently, the endoscopic transnasal technique has been introduced, and currently represents a good alternative for the surgical management of these lesions. This is a preliminary report on patients treated endoscopically for clival lesions by the authors' Skull Base Team.

PATIENTS AND METHODS

This was a retrospective chart review of patients who underwent an endoscopic exclusive transnasal approach (EEA) or a transoral one (TO) for clival lesions between June 2015 and November 2017 at our Skull Base Referral Center. Patient characteristics and symptoms, preoperative neuroradiological evaluation, surgical approach, complications, and postoperative results were evaluated.

RESULTS

Nine patients (6 females and 3 males; age range 6-82 years, mean 50.8 years) underwent EEA or TO. From histological analysis, we found chordomas (6/9 subjects), chondrosarcoma (1/9), craniopharyngioma (1/9), and eosinophilic granuloma (1/9). Three patients had previously been operated for a parasellar chondrosarcoma (1/9), a pituitary macroadenoma (1/9), or a chondroid chordoma (1/9). The lesions were totally (2/9) or sub-totally (5/9) resected, debulked (1/9), or analyzed with a biopsy (1/9). Reconstruction was accomplished with a multilayer technique (7/9), or with a gasket-seal (1/9), using a mucoperichondrial graft, a single/double nasoseptal flap, a middle turbinate flap, a fascia lata, or a synthetic fascia. One patient (11.1%) was re-operated on due to cerebrospinal leakage, without further complications. Two patients (22.2%) were re-operated on due to chordoma regrowth. Adjuvant chemotherapy was administered to 1/9 patient with progressive healing. All of the other patients underwent proton-beam radiotherapy with no documented tumor growth (median follow-up: 20 months; range 5.1-29.9 months).

CONCLUSIONS

Clival lesions represent a heterogeneous group of lesions located in a very complex and difficult area. EEA and TO approaches are safe and mini-invasive, with lower morbidity and with postoperative complications when compared to the traditional open approaches, according to the extent and type of pathology.

Investigating the application of diving endoscopic technique in determining the extent of pituitary adenoma resection via the trans-nasal-sphenoidal approach

The aim of the present study was to investigate the advantages and disadvantages of the diving endoscopic technique in pituitary adenoma surgery, and the application value in determining the extent of tumor resection. A total of 37 patients with pituitary adenoma initially underwent tumor resection under an endoscope-assisted microscope via standard trans-nasal-sphenoidal approach, and tumor cavity structure was observed by applying the diving endoscopic technique. Surgery was subsequently performed again under a microscope or endoscope. The diving endoscopic technique allowed surgeons to directly observe the structure inside a tumor cavity in high-definition. In the present study, 24 patients had pituitary macroadenomas or microadenomas that did not invade the cavernous sinus, and were considered to have undergone successful total resection. Among these patients, no tumor residues were observed through the diving endoscopic technique. Some white lichenoid or fibrous cord-like tissues in the tumor cavity were considered to be remnants of tumors. However, pathology confirmed that these were not tumor tissues. For tumors that invaded the cavernous sinus in 13 patients, observation could only be conducted under the angulation endoscope of the diving endoscope; i.e., the operation could not be conducted under an endoscope. The present study suggests that the diving endoscopic technique may be used to directly observe the resection extent of tumors within the tumor cavity, especially the structure of the tumor cavity inside the sella turcica. The present study also directly validates the reliability of pituitary adenoma resection under endoscope-assisted microscope. In addition, the diving endoscopic technique also allows the surgeon to observe the underwater environment within the sella turcica.

Endoscopic Endonasal Trans-sphenoidal Approach: Minimally Invasive Surgery for Pituitary Adenomas

Endoscopic endonasal trans-sphenoidal surgery has become the gold standard for the surgical treatment of pituitary adenomas and many other pituitary lesions. Refinements in surgical techniques, technological advancements, and incorporation of neuronavigation have rendered this surgery minimally invasive. The complication rates of this surgery are very low while excellent results are consistently obtained through this approach. This paper focuses on the step-by-step surgical approach to pituitary adenomas, which is based on personal experience, and details the results obtained with this minimally invasive surgery.

Frontal burr hole approach for neuroendoscopic resection of craniopharyngioma with the NICO Myriad device: report of two cases

OBJECTIVE

Craniopharyngiomas are challenging tumors to resect due to their deep location and proximity to vital structures. The perceived benefit of gross total resection may be tempered by the possibility of permanent disability. Minimally invasive techniques may reduce surgical morbidity while still allowing effective resection. The authors describe their initial experience with a neuroendoscopic transcortical, transventricular approach to two craniopharyngiomas. The surgeries were performed through a right frontal burr hole using the NICO Myriad, a side-cutting, aspiration device that fits through the working channel of a standard neuroendoscope.

METHODS

The imaging and medical records of two children (a 5-year-old male and a 9-year-old female) undergoing endoscopic resection of a craniopharyngioma with this technique were reviewed. Outcomes, results, and complications were noted.

RESULTS

A gross total resection was achieved in both patients. The operative time was 180 and 143 min, respectively. The estimated blood loss was 20 and 50 cm³, respectively. Both patients required a cerebrospinal fluid shunt. There were no surgical complications.

CONCLUSIONS

The NICO Myriad is an effective tool that allows a safe minimally invasive endoscopic resection of craniopharyngiomas in patients with amenable anatomy. Surgeons with experience in neuroendoscopy may be able to achieve a gross total resection of these challenging tumors through a minimally invasive burr hole approach.

Incidence and risk factors of subdural hematoma after intraoperative cerebrospinal fluid leakage during the transsphenoidal approach

PURPOSE

The transsphenoidal approach (TSA) is regarded as the first line of treatment for sellar and suprasellar lesions. There are only few case reports of postoperative subdural hematoma after TSA and extended transsphenoidal approach (eTSA), and the detailed incidence and risk factors for this complication are still unknown. We reviewed the incidence and risk factors for subdural hematoma after TSA and eTSA.

METHODS

Between January 1, 2013 and December 31, 2014, 165 consecutive patients underwent TSA or eTSA at Nagoya University Hospital and Nagoya Daini Red Cross Hospital. Fifty-one patients experienced intraoperative CSF leakage. Postoperative subdural hematoma was observed in 10 patients, all of whom experienced intraoperative CSF leakage. We reviewed clinical data including CT and MR images and examined factors related to subdural hematoma among patients with intraoperative CSF leakage.

RESULTS

In univariate statistical analyses, risk factors for postoperative subdural hematoma were advanced age, high Evans' index, and preoperative hypopituitarism. These factors were also significant in the multivariate logistic regression analysis. There were no statistical differences in sex, tumor size, approach methods, preoperative diabetes insipidus, or degree of intraoperative CSF leakage.

CONCLUSIONS

The incidence of postoperative subdural hematoma after intraoperative CSF leakage during TSA and eTSA was higher than the incidence reported in patients after craniotomy. Intraoperative CSF leakage should be avoided as much as possible, especially in patients with brain atrophy and/or enlargement of the ventricular system, even if the intent of the reconstruction technique is authenticity. In addition, patients with hypopituitarism should be carefully followed up after surgery.

[Endoscopic endonasal surgical treatment of large pituitary adenoma, spreading into the posterior fossa]

AIM

The objective of the study was to develop the tactics of surgical treatment of large and giant pituitary adenomas, spreading into the posterior cranial fossa.

MATERIAL AND METHODS

Patients with large hormonally inactive pituitary adenoma, extending to the right cavernous sinus and posterior cranial fossa.

RESULTS

The endoscopic endonasal removal a large endo-supra-latero(D)-retrosellar pituitary tumor was conducted. Control MRI shows that the tumor was removed radically. Oculomotor disturbances were observed in the early postoperative period, which significantly regressed within 6 months. The article provides detailed analysis of the world literature on the issue under discussion. Illustrative pre-, intra-, and post-operative photographs, as well as histological preparations are shown.

CONCLUSION

Modern minimally invasive techniques make it possible to remove large pituitary adenomas (and other tumors) of the posterior cranial fossa using endoscopic endonasal approach. Such operations must be carried out at highly specialized institutions by the surgeons who have extensive experience in endoscopic transnasal surgery of skull base tumors.

Extended endoscopic endonasal transsphenoidal approach for retrochiasmatic craniopharyngioma: Surgical technique and results

Objective:

Surgical treatment of retrochiasmatic craniopharyngioma still remains a challenge. While complete removal of the tumor with preservation of the vital neurovascular structures is often the goal of the treatment, there is no optimal surgical approach available to achieve this goal. Transcranial and transsphenoidal microsurgical approaches, commonly used in the past, have considerable technical limitations. The extended endonasal endoscopic surgical route, obtained by removal of tuberculum sellae and planum sphenoidale, offers direct midline access to the retrochiasmatic space and provides excellent visualization of the undersurface of the optic chiasm. In this report, we describe the technical details of the extended endoscopic approach, and review our results using this approach in the surgical management of retrochiasmatic craniopharyngiomas.

Methods:

Fifteen children, including 9 girls and 6 boys, aged 8 to 15 years underwent surgery using extended endoscopic transsphenoidal approach between 2008 and 2014. Nine patients had a surgical procedure done previously and presented with recurrence of symptoms and regrowth of their residual tumors.

Results:

A gross total or near total excision was achieved in 10 (66.7%) patients, subtotal resection in 4 (26.7%), and partial removal in 1 (6.7%) patient. Postoperatively, headache improved in 93.3%, vision recovered in 77.3%, and the hormonal levels stabilised in 66.6%. Three patients (20%) developed postoperative CSF leaks which were managed conservatively. Three (20%) patients with diabetes insipidus and 2 (13.3%) with panhypopituitarism required long-term hormonal replacement therapy.

Conclusions:

Our early experience suggests that the extended endonasal endoscopic approach is a reasonable option for removal of the retrochiasmal craniopharyngiomas. Compared to other surgical approaches, it provides better opportunities for greater tumor removal and visual improvement without any increase in risks.

Magnetic resonance imaging fluid-attenuated inversion recovery sequence signal reduction after endoscopic endonasal transcribiform total resection of olfactory groove meningiomas

BACKGROUND

Olfactory groove meningiomas grow insidiously and compress adjacent cerebral structures. Achieving complete removal without further damage to frontal lobes can be difficult. Microsurgical removal of large lesions is a challenging procedure and usually involves some brain retraction. The endoscopic endonasal approaches (EEAs) for tumors arising from the anterior fossa have been well described; however, their effect on the adjacent brain tissue has not. Herein, the authors utilized the magnetic resonance imaging fluid attenuated inversion recovery (FLAIR) sequence signal as a marker for edema and gliosis on pre- and post-operative images of olfactory groove meningiomas, thus presenting an objective parameter for brain injury after surgical manipulation.

METHODS

Imaging of 18 olfactory groove meningiomas removed through EEAs was reviewed. Tumor and pre/postoperative FLAIR signal volumes were assessed utilizing the DICOM image viewer OsiriX(®). Inclusion criteria were: (1) No previous treatment; (2) EEA gross total removal; (3) no further treatment.

RESULTS

There were 14 females and 4 males; the average age was 53.8 years (±8.85 years). Average tumor volume was 24.75 cm(3) (±23.26 cm(3), range 2.8-75.7 cm(3)), average preoperative FLAIR volume 31.17 cm(3) (±39.38 cm(3), range 0-127.5 cm(3)) and average postoperative change volume, 4.16 cm(3) (±6.18 cm(3), range 0-22.2 cm(3)). Average time of postoperative scanning was 6 months (range 0.14-20 months). In all cases (100%) gross total tumor removal was achieved. Nine patients (50%) had no postoperative FLAIR changes. In 2 patients (9%) there was minimal increase of changes postoperatively (2.2 cm(3) and 6 cm(3) respectively); all others demonstrated image improvement. The most common complication was postoperative cerebrospinal fluid leakage (27.8%); 1 patient (5.5%) died due to systemic complications and pulmonary sepsis.

CONCLUSIONS

FLAIR signal changes tend to resolve after endonasal tumor resection and do not seem to worsen with this operative technique.

Repair and prevention of cerebrospinal fluid leakage in transsphenoidal surgery: a sphenoid sinus mucosa technique

Cerebrospinal fluid (CSF) leakage is a common but sometimes serious complication after transsphenoidal surgery (TSS). To avoid this postsurgical complication, we usually repair the CSF leaking area using an autologous material, such as fat, fascia, or muscle graft and sometimes nasonasal septal flap. In this report, we propose a technique using a novel autologous material, sphenoid sinus mucosa (SSM), to repair intraoperative CSF leakage or prevent it postoperatively. On 26 February 2007, we introduced the technique of using SSM to repair or prevent CSF leakage in TSS. Until 30th of June 2014, we performed 500 TSSs for patients with pituitary or parasellar lesions. They were 195 men and 305 women with a mean age of 48.5 years (range, 5-85 years). We used SSM for patching or suturing the arachnoid laceration or dural defect, in lieu of fat or fascia harvested from abdomen or thigh, or made pedicle flap of SSM instead of nasonasal septal flap to cover the sellar floor. Comparing the previous 539 cases not using these techniques before 26 February 2007, intraoperative CSF leakage increased from 49 to 69.4% (p < 0.0001) due to more aggressive surgical technique, mainly related to more extensive approaches and lesion removals, but the rate of using fat was reduced significantly from 35.5 to 19.4% (p = 0.00021) in small or moderate CSF leaks during TSS without increasing the reoperation rate for postoperative CSF leaks (1.86 vs 1.2%, p = 0.45). The technique of using SSM to repair intraoperative CSF leaks or prevent them postoperatively in TSS was considered useful, effective, less invasive, easier for graft harvesting (same surgical field), and providing natural anatomical reconstruction, without potential donor site morbidity. We can recommend it as a standard method for CSF leaks repair and prevention in TSS.

Endoscopic transnasal interseptal approach for invasive clival tumors: development of an approach method regarding maximal preservation of the nasal anatomy

Asian people frequently show small noses, narrow nasal apertures, and congestive mucosa on the turbinates and septum. To reduce the risk of nasal morbidity with increased radicality for skull base tumors in these patients, we developed endoscopic transnasal interseptal approach (ETISA) in transsphenoidal surgery for invasive clival tumors (ICTs). Indication for ETISA is radical resection for tumors occupying deep ventral skull base regions, confined posterior to the level of the middle turbinates. After removing ethmoidal air cells, the middle turbinates are laterally deflected. A linear incision is made vertically on each side of the septal mucosa, which is separated from the bony septum as far as the sphenoid rostrum. The blades of an adjustable speculum are inserted submucosally, and the bony septum is temporarily displaced. The surgical pathway is widely maintained from the entrance to the deep surgical field without sacrificing the nasal mucosa and turbinates. Thirty-two consecutive patients with clival tumors (18 chordomas, 11 chondrosarcomas, 3 others) were treated. Bilateral middle turbinectomy was routinely performed in the initial 3 patients, but in only 4 of the remaining 29 (3 unilaterally, 1 bilaterally). Tumor was sufficiently resected in 29 patients (90.6%; gross total removal n = 25, subtotal resection n = 4). As complications, 6 patients showed mild and transient worsening of cranial nerve symptoms. Nasal complications arose in 3 patients, persisting > 3 months in 2 (5.7%). This approach allows fine bimanual handling and swift delivery of surgical equipment while reasonably preserving the nasal anatomy, which is useful in endoscopic transsphenoidal surgery for ICT.

Endoscopic endonasal trans-sphenoid management of craniopharyngiomas

Introduction:

Craniopharyngiomas treatment has been challenging because of their anatomical location. The endoscopic endonasal (EE) trans-sphenoidal approach is indicated in sellar, supra sellar, selected intraventricular lesions in adults and children. We are reporting our initial experience of 44 patients managed by EE approach.

Materials and Methods:

This is a retrospective study of 44 craniopharyngiomas. The goal of surgery was gross-total resection in all cases. All patients underwent pre- and post-operative comprehensive ophthalmological and endocrinological evaluation. Lumbar drain at the start of the operation was used in all cases with tumor larger than 3 cm maximum diameter. Binostril technique vascularized nasoseptal flap and multilayer closure of the dural defect were used. Wide sphenoidotomy, posterior ethmoidectomy, tuberculum selle, and planum removal were performed in all cases. Perioperative antibiotic prophylaxis was used for 72 h.

Results:

There were 44 patients of age ranging from 8 to 65 (mean: 42) years. Diameter of the tumor varied from 3.1 cm to 6.6 cm (average: 4.3 cm). Visual and pituitary dysfunctions were observed in 44 and 33, respectively, before surgery. Vision improvement, gross-total removal, cerebrospinal fluid (CSF) leak and recurrence were observed in 34, 26, four and six patients, respectively. Average follow-up was 19 months.

Conclusion:

Endoscopic endonasal trans-sphenoidal approach for craniopharyngioma is safe and effective alternative to transcranial approach in selected patients. Although this technique is associated with effective tumor removal and improved visual outcome, CSF leak, and endocrine dysfunctions remain a major challenge.

Fascia patchwork closure for endoscopic endonasal skull base surgery

With the development of endoscopic technology and surgery, resection of midline skull base tumors has been achieved using endoscopic endonasal skull base (EESB) approaches. EESB approaches reportedly have a greater risk of postoperative cerebrospinal fluid (CSF) leakage. Recently, the introduction of the nasoseptal flap (NSF) decreased dramatically the incidence of CSF leakage, but the use of an NSF increases the risk of disturbing the function of the nose. Here, we report our new technique called "fascia patchwork closure" for closure after EESB surgery and its outcome. All 48 cases involved midline skull base tumors resected via EESB approaches. Of them, 32 cases were closed by the fascia patchwork technique after tumor resection, and there was no incidence of CSF leakage. Moreover, 6 of the 32 cases were closed without the use of an NSF, indicating that the fascia patchwork closure approach is effective as part of a multilayer closure for the prevention of CSF leakage. The establishment and popularization of this technique might result in the further development of EESB surgery and also an improvement of postoperative nasal function.

Risk factors for postoperative cerebrospinal fluid leak and meningitis after expanded endoscopic endonasal surgery

Postoperative cerebrospinal fluid (CSF) leak is a serious complication of transsphenoidal surgery, which can lead to meningitis and often requires reparative surgery. We sought to identify preoperative risk factors for CSF leaks and meningitis. We reviewed 98 consecutive expanded endoscopic endonasal surgeries performed from 2008-2012 and analyzed preoperative comorbidities, intraoperative techniques, and postoperative care. Univariate and multivariate analyses were performed. The most common pathologies addressed included pituitary adenoma, Rathke cyst, chordoma, esthesioneuroblastoma, meningioma, nasopharyngeal carcinoma, and squamous cell carcinoma. There were 11 CSF leaks (11%) and 10 central nervous system (CNS) infections (10%). Univariate and multivariate analysis of preoperative risk factors showed that patients with non-ideal body mass index (BMI) were associated with higher rate of postoperative CSF leak and meningitis (both p<0.01). Also, patients with increasing age were associated with increased CSF leak (p = 0.03) and the length of time a lumbar drain was used postoperatively was associated with infection in a univariate analysis. In addition, three of three endoscopic transsphenoidal surgeries combined with open cranial surgery had a postoperative CSF leak and CNS infection rate which was a considerably higher rate than for transsphenoidal surgeries alone or surgeries staged with open cases (p<0.01 and p=0.04, respectively) In this series of expanded endoscopic transsphenoidal surgeries, preoperative BMI remains the most important preoperative predictor for CSF leak and infection. Other risk factors include age, intraoperative CSF leak, lumbar drain duration, and cranial combined cases. Risks associated with complex surgical resections when combining open and endoscopic approaches could be minimized by staging these procedures.

Extended endoscopic transsphenoidal approach infrachiasmatic corridor

An extended endoscopic transsphenoidal approach is required for skull base lesions extending to the suprasellar area. Inferior approach using the infrachiasmatic corridor allows access to the lesions through the tumor growth that is favorable for the extended transsphenoidal approaches. Infrachiasmatic corridor is a safer route for the inferior approaches that is made up by basal arachnoid membrane and Liliequist's membrane with its leaves (diencephalic and mesencephalic leaf). This area extends from the optic canal and tuberculum sella to the corpus mamillare. We performed extended endoscopic approach using the infrachiasmatic corridor in 52 cases, including tuberculum sella meningiomas (n:23), craniopharyngiomas (n:16), suprasellar Rathke's cleft cyst (n:6), pituitary adenoma (n:2), fibrous dysplasia (n:1), infundibular granulosa cell tumor (n:2), and epidermoid tumor (n:2). Total resection was achieved in 17 of 23 (74%) with tuberculum sellae meningioma using infrachiasmatic approach. Twenty patients presented with visual disorders and 14 of them improved. There were two postoperative cerebrospinal fluid (CSF) leakages and one transient diabetes insipidus and one permanent diabetes insipidus. Sixteen patients were operated on by the infrachiasmatic approach for craniopharyngiomas. Improvement was reached in seven of eight patients presented with visual disorders. Complete tumor resection was performed in 10 of 16 cases and cyst aspiration in 4 cases, and there were remnants in two cases. Postoperative CSF leakage was seen in two patients. Infrachiasmatic corridor provides an easier and safer inferior route for the removal of middle midline skull base lesions in selected cases.

Endoscopic endonasal skull base approach for parasellar lesions: Initial experiences, results, efficacy, and complications

BACKGROUND

Endoscopic surgery is suitable for the transsphenoidal approach; it is minimally invasive and provides a well-lit operative field. The endoscopic skull base approach through the large opening of the sphenoid sinus through both nostrils has extended the surgical indication for various skull base lesions. In this study, we describe the efficacy and complications associated with the endoscopic skull base approach for extra- or intradural parasellar lesions based on our experiences.

METHODS

Seventy-four cases were treated by an endoscopic skull base approach. The indications for these procedures included 55 anterior extended approaches, 10 clival approaches, and 9 cavernous approaches. The operations were performed through both the nostrils using a rigid endoscope. After tumor removal, the skull base was reconstructed by a multilayered method using a polyglactin acid (PGA) sheet.

RESULTS

Gross total resection was achieved in 82% of pituitary adenomas, 68.8% of meningiomas, and 60% of craniopharyngiomas in anterior extended approach and in 83.3% of chordomas in clival approach, but only in 50% of the tumors in cavernous approach. Tumor consistency, adhesion, and/or extension were significant limitations. Visual function improvements were achieved in 37 of 41 (90.2%) cases. Cerebrospinal fluid (CSF) leakage (9.5%), infections (5.4%), neural injuries (4.1%), and vascular injuries (2.7%) were the major complications.

CONCLUSIONS

Our experiences show that the endoscopic skull base approach is a safe and effective procedure for various parasellar lesions. Selection of patients who are unlikely to develop complications seems to be an important factor for procedure efficacy and good outcome.

Neuroendoscopic transnasal surgery for skull base tumors: basic approaches, avoidance of pitfalls, and recent innovations

Since the introduction of endoscopic technology in the neurosurgical field, the role of transnasal surgery has been dramatically enlarged. With this technique, we can approach the anterior cranial base, parasellar region, clivus, cavernous sinus, and craniovertebral junction, less invasively than with conventional microsurgery. This review describes the two major approach methods in endoscopic skull base surgery, the endonasal approach and the transseptal approach. The endonasal approach uses two nostrils without nasal specula and the mucosa on the sphenoid rostrum and the posterior margin of the nasal septum are removed. In the transseptal approach, only a single nostril is available, but using the nasal speculum, sufficient surgical field can be obtained with only a small incision on the septum. In either approach method, it is very important to avoid excessive mucosal damage and to select the appropriate approach for each patient. The endoscopic skull base approach is one of the least invasive surgical procedures, which is a very promising therapeutic choice with potential for further advances. For better surgical outcomes and further progress, cooperation with rhinolaryngologists who have much more knowledge and experience about nasal surgery than neurosurgeons is essential. We believe this article will contribute to the development of safe and effective surgical procedures, and to the benefit of the patients suffering with intractable skull base lesions.

Initial experiences with endoscopic rhino-neurosurgery in Amsterdam

Endoscopic surgery of the skull base has been on the rise for several years. Endoscopic access for surgery can be achieved from the frontal sinus anteriorly along the skull base to the odontoid process posterior inferiorly. An endoscope is inserted through one nasal corridor and allows visualization of the working field and up to three surgical instruments can be used to address the lesion. This is called the "two nostrils-four hands technique". This is a retrospective study of 67 cases. Setting of the study is an Amsterdam University hospital. Cases were identified in the department of otorhinolaryngology and department of neurosurgery database. All patients operated between 1 January, 2008 and 1 February, 2012 with pituitary tumours that extend beyond the sella, sinonasal tumours and all non-pituitary skull-base tumours were included. Mean tumour diameter was 3.8 cm. We performed a near-to-gross total resection in 92% of cases where we intended to perform a total resection. The most frequent complication was CSF leakage. This study demonstrates that this technique is safe and reliable. What is needed is a dedicated team, which includes a dedicated anesthesiologist, endocrinologist, ophthalmologist, and radiation oncologist.

The risk of meningitis following expanded endoscopic endonasal skull base surgery: a systematic review

Objective To examine the risk of postoperative meningitis following expanded endoscopic endonasal skull base (EESB) surgery. Setting A systematic analysis of publications identified through searches of the electronic databases from Embase (1980-July 17, 2012), Medline (1950-July 17, 2012), and references of review articles. Main Outcome Measures Incidence of meningitis following EESB surgery. Results A total of 2,444 manuscripts were selected initially, and full-text analysis produced 67 studies with extractable data. Fifty-two contained data regarding the frequency of postoperative meningitis. The overall risk of postoperative meningitis following EESB surgery was 1.8% (36 of 2,005). For those reporting a cerebrospinal fluid (CSF) leak, meningitis occurred in 13.0% (35 of 269). For those not reporting a CSF leak, meningitis occurred in 0.1% (1 of 1,736). The odds ratio for the development of meningitis in the presence of a postoperative CSF leak was 91.99 (95% confidence interval, 11.72-721.88; p < 0.01). There was no difference in reported incidence of meningitis or CSF leak between anterior and posterior cranial fossa surgery. There was one reported case of meningitis-related mortality following EESB surgery. Conclusion The evidence in skull base surgery is limited. This study demonstrates a low incidence of meningitis (1.8%) following EESB procedures. The incidence of meningitis from EESB surgery without an associated CSF leak is uncommon.

Single-surgeon fully endoscopic endonasal transsphenoidal surgery: outcomes in three-hundred consecutive cases

The objective of this study was to evaluate outcomes of endoscopic transsphenoidal surgery using a single-surgeon technique as an alternative to the more commonly employed two-surgeon, three-hand method. Three hundred consecutive endoscopic transsphenoidal procedures performed over a 5 year period from 2006 to 2011 were reviewed. All procedures were performed via a binasal approach utilizing a single surgeon two handed technique with a pneumatic endoscope holder. Expanded enodnansal cases were excluded. Surgical technique, biochemical and surgical outcomes, and complications were analyzed. 276 patients underwent 300 consecutive surgeries with a mean follow-up period of 37 ± 22 months. Non-functioning pituitary adenoma (NFPA) was the most common pathology (n = 152), followed by growth hormone secreting tumors (n = 41) and Rathke's cleft cysts (n = 30). Initial gross total cyst drainage based on radiologic criteria was obtained in 28 cases of Rathke's cleft cyst, with 5 recurrences. For NFPA and other pathologies (n = 173) gross total resection was obtained in 137 cases, with a 92% concordance rate between observed and expected extent of resection. For functional adenoma, remission rates were 30/41 (73%) for GH-secreting, 12/12 (100%) for ACTH-secreting, and 8/17 (47%) for prolactin-secreting tumors. Post-operative complications included transient (11%) and permanent (1.4%) diabetes insipidus, hyponatremia (13%), and new anterior pituitary hormonal deficits (1.4%). CSF leak occurred in 42 cases (15%), and four patients required surgical repair. Two carotid artery injuries occurred, both early in the series. Epistaxis and other rhinological complications were noted in 10% of patients, most of which were minor and diminished as surgical experience increased. Fully endoscopic single surgeon transsphenoidal surgery utilizing a binasal approach and a pneumatic endoscope holder yields outcomes comparable to those reported with a two-surgeon method. Endoscopic outcomes appear to be better than those reported in microscope-based series, regardless of a one or two surgeon technique.

Effectiveness of lumbar drain versus hyperventilation to facilitate transsphenoidal pituitary (suprasellar) adenoma resection

BACKGROUND

Developing controlled hypercarbia is a known scheme of lowering the suprasellar part of the adenoma in order to assist the surgeon, which acts through raising the ICP and therefore the CSF pressure.

OBJECTIVES

The purpose of this study is to compare the effect of introducing a lumbar drain with that of controlled hypercapnia on the quality of transsphenoidal pituitary tumor resection and CSF leak.

PATIENTS AND METHODS

Fifty two patients with pituitary adenoma who underwent transsphenoidal hypophysectomy by the same surgeon were included. They were randomly divided into two groups. A lumbar drain catheter introduced into the L3-L4 subarachnoid space under local anesthesia in all patients. The same anesthesia was performed in both groups. In the study group, we used a saline injection into the subarachnoid space versus hypoventilation in the control group in order to increase the ICP according to the surgeon's request. The surgeon's satisfaction during the tumor resection and the resection time were assessed during the surgery. The CSF catheter was closed and sent with the patient for CSF drainage. If there was no CSF leak, the catheter removed 24 hours later. With evidence of a CSF leak, we used the catheter as a lumbar drain. The time taken for the leakage control was assessed.

RESULTS

The satisfaction came from 21 (87.5%) and 2 (9.1%) for surgeon in the first and the second group respectively (P = 0.0001). CSF leakage time in the first and the second group was 1.6 ± 0.24 and 5 ± 0.50 respectively. It revealed a significant difference between the two groups (P = 0.001). The mean resection time was 13.54 ± 0.66 minutes in the study group; and 30.91 ± 0.98 minutes in the control group.

CONCLUSIONS

In summary, the method described here for ICP manipulation is an effective procedure for a better visualization of the pituitary tumor during transphenoidal resection by surgeon and beneficial in managing the CSF leak following surgery.

Surgery for craniopharyngioma

Craniopharyngiomas are rare benign sellar region tumors, which are diagnosed either in childhood or adolescence due to local mass effects on visual pathways, pituitary and hypothalamus, or because of an increased intracranial pressure resulting from obstructive hydrocephalus. The neurosurgeons challenge is to achieve tumor control without aggravating the symptoms. There are essentially two different surgical philosophies. Although only gross tumor resection has been proven to provide cure, the accompanying surgical hazard is substantial. Thus, less aggressive operations with partial or subtotal tumor resection or drainage of cystic portions followed by irradiation may relieve the patient's symptoms and benefit the patient more than a heroic tumor resection-since to date several variants of radiation therapy are available which also serve to control tumor progression. In the present brief review, the surgical techniques and outcomes of operations in craniopharyngiomas with special focus on the resulting morbidity and mortality are summarized.

A systematic review of the results of surgery and radiotherapy on tumor control for pediatric craniopharyngioma

OBJECTIVE

Craniopharyngiomas are rare tumors with bimodal incidence in the pediatric and adult age groups. Treatment strategies range from aggressive resection to planned limited resection combined with adjuvant therapies. Currently there is no consensus for standard of care for pediatric craniopharyngioma.

MATERIALS AND METHODS

We performed a systematic review of the published literature on pediatric craniopharyngioma. Patients were grouped based on extent of resection into gross total resection (GTR), subtotal resection (STR), and biopsy procedures. These groups were compared with respect to tumor control. Chi square was used to compare rates of recurrence. Kaplan-Meier was used to generate progression-free survival (PFS) estimates. Cox proportional hazard modeling was used to evaluate risk of progression. Each extent of resection group was also subdivided based on adjuvant therapy and compared.

RESULTS

A total of 109 studies described extent of resection resulting in a cohort of 531 patients. Recurrence data were available for 377 patients. There was no difference in 1- or 5-year PFS between the groups who underwent GTR and STR combined with radiation (XRT; log-rank; p = 0.76; 1-year PFS 89 vs 84%; 5-year PFS 77 vs 73%, respectively). One-year PFS was 84% for STR+XRT compared to 76% for STR alone while 5-year PFS was 73% for STR+XRT compared to 43% for STR alone (log-rank; p = 0.003).

CONCLUSION

Although there are limitations of a systematic review of retrospective data, our results suggest that STR+XRT of pediatric craniopharyngioma is associated with similar rates of tumor control as GTR.

The efficacy and safety of preoperative lumbar drain placement in anterior skull base surgery

This study assesses the efficacy of preoperative lumbar drain (LD) placement prior to elective open cranial and endoscopic anterior skull base (ASB) surgery in reducing postoperative cerebrospinal fluid (CSF) leak. A retrospective review of 93 patients who underwent LD placement at our institution between 2006 and 2011 was performed. Of these patients, 43 underwent elective LD placement prior to ASB surgery; 2 patients had evidence of CSF rhinorrhea prior to surgery, and 41 had no evidence of a preoperative CSF leak. Of those 41 patients, 2 developed CSF rhinorrhea (2/41= 4.9%) as a result of surgery—all in our endoscopic patient population (N = 21; 2/21= 9.5%). No postoperative CSF leaks were noted in our open ASB surgery cohort (N = 20). Other complications were rare, but we encountered two instances of delayed malignant cerebral edema in the open ASB cohort that are discussed in detail. Overall, preoperative LD placement was found to be an effective means of preventing postoperative CSF leaks after ASB approaches, but potential and significant intracranial complications may occur in select patients that merit careful consideration prior to LD placement.

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.

Endoscopic transcranial and intracranial resection: case series and design of a perioperative management protocol

Purely endoscopic resections of transcranial/intracranial pathology represent an exciting minimally invasive option for some patients. There is an abundance of literature on surgical techniques, though very little deals with perioperative management, which is critical for good outcomes. We present a detailed case review and a perioperative management protocol with specific reference to skull base and neuroanatomy. We performed a retrospective chart review and analysis of outcomes and complications by approach and design and prospective employment of a perioperative management protocol in a major tertiary care referral hospital. We included patients undergoing endoscopic skull base approaches by the two senior surgeons from September 2005 to April 2009, selecting of transcranial/intracranial cases for detailed review. Our main outcome measures included perioperative morbidity, mortality, and complications; degree of resection; recurrence rate; and survival. Fifteen patients met study criteria. No perioperative mortality occurred. There were two major and four minor complications. Mean follow-up was 15 months; 11/13 patients with malignancies had no evidence of disease. A perioperative management protocol was designed from these data and has resulted in decreased lumbar drainage and increased fluid/electrolyte monitoring. Endoscopic transcranial/intracranial anterior skull base surgery is both safe and effective when a complete understanding of the surgery and perioperative management is achieved.

The endoscopic endonasal approach for the management of craniopharyngiomas involving the third ventricle

The third ventricle has historically represented one of the most challenging areas to access surgically, so that lesions directly harboring into the ventricular chamber or secondarily extending into it from adjacent areas have been approached by means of different transcranial routes. The aim of this work is to report our experience with the endoscopic endonasal approach in the management of a series of patients affected by craniopharyngiomas, extending into or arising from the third ventricle, evaluating pros and cons of this technique, also in regards of the anatomy and the pathology dealt with. During the period between January 2001 and February 2011, 12 patients, 9 male and 3 female (mean age 50.4 years; range 12-68) underwent an endoscopic endonasal approach for the treatment of a craniopharyngioma involving or arising from the third ventricle. According to the grade of involvement of the third ventricle, we identified three main ventricular growth patterns: (1) stalk-infundibulum; (2) infundibulum-ventricular chamber; (3) stalk-infundibulum-ventricular chamber. Though gross total removal was achieved in eight patients (66.7%), in three patients (25%) was possible a near total removal (>95%) and only in one case (8.3%) tumor removal has been partial (<50%). The overall analysis revealed a rate of 77.8% improvement of post-operative visual defects. Concerning the complications, we reported an overall CSF rate of 16.7%; two patients developed a subdural hematoma that has been treated with a surgical drainage. One patient died after the occurrence of a brainstem hemorrhage. The endoscopic endonasal route provides a good exposure, especially of the sub- and retro-chiasmatic areas, as well as of the stalk-infundibulum axis, which represents, when directly involved by a lesion, a gate to access the third ventricle chamber. Despite this study reporting only a preliminary experience, it seems that in properly selected cases--namely tumors growing mostly along the pituitary stem-infundibulum-third ventricle axis--this approach could be advocated as a valid route among the wide kaleidoscope of surgical approaches to the third ventricle.

The transnasal approach to the skull base. From sinus surgery to skull base surgery

The indications for endonasal endoscopic approaches to diseases of the skull base and its adjacent structures have expanded considerably during the last decades. This is not only due to improved technical possibilities such as intraoperative navigation, the development of specialized instruments, and the compilation of anatomical studies from the endoscopic perspective but also related to the accumulating experience with endoscopic procedures of the skull base by multidisciplinary centers. Endoscopic endonasal operations permit new approaches to deeply seated lesions and are characterized by a reduced manipulation of neurovascular structures and brain parenchyma while at the same time providing improved visualization. They reduce the trauma caused by the approach, avoid skin incisions and minimize the surgical morbidity. Transnasal endoscopic procedures for the closure of small and large skull base defects have proven to be reliable and more successful than operations with craniotomies. The development of new local and regional vascularized flaps like the Hadad-flap have contributed to this. These reconstructive techniques are furthermore effectively utilized in tumor surgery in this region. This review delineates the classification of expanded endonasal approaches in detail. They provide access to lesions of the anterior, middle and partly also to the posterior cranial fossa. Successful management of these complex procedures requires a close interdisciplinary collaboration as well as continuous education and training of all team members.

Extended endoscopic endonasal skull base surgery: from the sella to the anterior and posterior cranial fossa

Skull base surgery has gone through significant changes with the development of extended endoscopic endonasal approaches over the last decade. Initially used for the transphenoidal removal of hypophyseal adenomas, the endoscopic transnasal approach gradually evolved into a way of accessing the whole ventral skull base. Improved visualization, avoidance of brain retraction, the ability to access directly tumours with minimal damage to critical neurosurgical structures as well lack of external scars are among its obvious benefits. However, it presents the surgeons with a number of challenges, including the need to deal endoscopically with potential arterial bleeding, complicated reconstruction requirements as well as the need for a true team approach. In this review drawing from our experience as well as published series, we present an overview of current indications, challenges and limitations of the expanded endonasal approaches to the skull base.

Infundibulo-tuberal or not strictly intraventricular craniopharyngioma: evidence for a major topographical category

PURPOSE

This study investigates retrospectively the clinical, neuroradiological, pathological and surgical evidence verifying the infundibulo-tuberal topography for craniopharyngiomas (CPs). Infundibulo-tuberal CPs represent a surgical challenge due to their close anatomical relationships with the hypothalamus. An accurate definition of this topographical category is essential in order to prevent any undue injury to vital diencephalic centres.

METHODS

A systematic review of all scientific reports involving pathological, neuroradiological or surgical descriptions of either well-described individual cases or large series of CPs published in official journals and text books from 1892 to 2011 was carried out. A total of 1,232 documents providing pathological, surgical and/or neuroradiological evidence for the infundibulo-tuberal or hypothalamic location of CPs were finally analysed in this study.

FINDINGS

For a total of 3,571 CPs included in 67 pathological, surgical or neuroradiological series, 1,494 CPs (42%) were classified as infundibulo-tuberal lesions. This topography was proved in the autopsy of 122 non-operated cases. The crucial morphological finding characterizing the tubero-infundibular topography was the replacement of the third ventricle floor by a lesion with a predominant intraventricular growth. This type of CP usually presents a circumferential band of tight adherence to the third ventricle floor remnants, formed by a functionless layer of rective gliosis of a variable thickness. After complete surgical removal of an infundibulo-tuberal CP, a wide defect or breach at the floor of the third ventricle is regularly observed both in the surgical field and on postoperative magnetic resonance imaging studies.

CONCLUSIONS

Infundibulo-tuberal CPs represent a major topographical category of lesions with a primary subpial development at the floor of the third ventricle. These lesions expand within the hypothalamus itself and subsequently occupy the third ventricle; consequently, they can be classified as not strictly intraventricular CPs. A tight attachment to the hypothalamus and remnants of the third ventricle floor is the pathological landmark of infundibulo-tuberal CPs.

Endoscopic optic canal decompression for compressive optic neuropathy

Compressive optic neuropathy is a rare condition that may be caused by trauma or non-traumatic events. Endoscopic techniques have evolved to provide an easier surgical approach to decompression. The aim of this study was to determine the endoscopic anatomy of the orbital apex and to identify the optimal targets for endoscopic optic nerve decompression. We report five patients with endoscopic optic nerve decompression: two with traumatic optic neuropathies, two with fibrous dysplasias, and one with chordoma. For these lesions, the major treatment concern was removal of the bony structures around the optic nerve. All compressive lesions were removed effectively via an endoscopic endonasal route. Following endoscopic optic nerve decompression, three patients had markedly improved visual acuity and fields of vision, one patient had improved fields of vision without change in visual acuity, and one patient had improved visual acuity alone. There were no operative complications. Adequate exposure of the intracanalicular portion of the optic nerve was essential for effective decompression, and to achieve this, decompression of the roof as well as medial wall of the intracanalicular portion was critical. We conclude that endoscopic optic canal decompression is a minimally invasive, safe, and efficient treatment for compressive optic neuropathy regardless of etiology.