Endoscopic Endonasal Skull Base Research Articles

Impact of sinonasal anatomic changes after endoscopic anterior skull base surgery on nasal airflow and air conditioning: a computational fluid dynamics study

Objective: To analyze the impact of the sinonasal anatomic changes after endonasal endoscopic anterior skull base surgery on the nasal airflow and heating and humidification by computational fluid dynamics (CFD), and to explore the correlation between the postoperative CFD parameters and the subjective symptoms of the patients. Methods: The clinical data in the Rhinology Department of the First Affiliated Hospital of Zhengzhou University from 2016 to 2021 were retrospectively analyzed. The patients received the endoscopic resection of the anterior skull base tumor were selected as the case group, and the adults whose CT scans had no sinonasal abnormalities were chosen as the control group. The CFD simulation was performed on the sinonasal models after reconstructed from the patients' sinus CT images during the post-surgical follow-up. All the patients were asked to complete the Empty Nose Syndrome 6-Item Questionnaire (ENS6Q) to assess the subjective symptoms. The comparison between two independent groups and the correlation analysis were carried out by using the Mann-Whitney U test and the Spearman correlation test in the SPSS 26.0 software. Results: Nineteen patients (including 8 males and 11 females, from 22 to 67 years old) in the case group and 2 patients (a male of 38 years old and a female of 45 years old) in the control group were enrolled in this study. After the anterior skull base surgery, the high-speed airflow moved to the upper part of the nasal cavity, and the lowest temperature shifted upwards on the choana. Comparing with the control group, the ratio of nasal mucosal surface area to nasal ventilation volume in the case group decreased [0.41 (0.40, 0.41) mm-1 vs 0.32 (0.30, 0.38) mm-1; Z=-2.04, P=0.041], the air flow in the upper and middle part of the nasal cavity increased [61.14 (59.78, 62.51)% vs 78.07 (76.22, 94.43)%; Z=-2.28, P=0.023], the nasal resistance decreased [0.024 (0.022, 0.026) Pa·s/ml vs 0.016 (0.009, 0.018) Pa·s/ml; Z=-2.29, P=0.022], the lowest temperature in the middle of the nasal cavity decreased [28.29 (27.23, 29.35)℃ vs 25.06 (24.07, 25.50)℃; Z=-2.28, P=0.023], the nasal heating efficiency decreased [98.74 (97.95, 99.52)% vs 82.16 (80.24, 86.91)%; Z=-2.28, P=0.023], the lowest relative humidity decreased [(79.62 (76.55, 82.69)% vs 73.28 (71.27, 75.05)%; Z=-2.28, P=0.023], and the nasal humidification efficiency decreased [99.50 (97.69, 101.30)% vs 86.09 (79.33, 87.16)%; Z=-2.28, P=0.023]. The ENS6Q total scores of all patients in the case group were less than 11 points. There was a moderate negative correlation between the proportion of the inferior airflow in the post-surgical nasal cavity negatively and the ENS6Q total scores (rs=-0.50, P=0.029). Conclusions: The sinonasal anatomic changes after the endoscopic anterior skull base surgery alter the nasal airflow patterns, reducing the efficiency of nasal heating and humidification. However, the post-surgical occurrence tendency of the empty nose syndrome is weak.

Evolution of Radiographic Changes of a Vascularized Pedicled Nasoseptal Flap after Endonasal Endoscopic Skull Base Surgery.

There is active research involving the radiographic appearance of the skull base following reconstruction. The purpose of this study was to describe the radiographic appearance of the vascularized pedicle nasoseptal flap after endoscopic skull base surgery across time. We performed chart and imaging review of all patients with intraoperative nasoseptal flap placement during endoscopic skull base surgery at a tertiary academic skull base surgery program between July 2018 and March 2021. All patients underwent immediate and delayed (>3 months) postoperative MR imaging. Primary outcome variables included flap and pedicle enhancement, flap thickness, and flap adherence to the skull base. Sixty-eight patients were included. Flap (P = .003) enhancement significantly increased with time. Mean nasoseptal flap thickness on immediate and delayed postoperative scans was 3.8 and 3.9 mm, respectively (P = .181). The nasoseptal flap adhered entirely to the skull base in 37 (54.4%) and 67 (98.5%) patients on immediate and delayed imaging, respectively (P < .001). Our findings demonstrate heterogeneity of the nasoseptal flap appearance after skull base reconstruction. While it is important for surgeons and radiologists to evaluate variations in flap appearance, the absence of enhancement and lack of adherence to the skull base on immediate postoperative imaging do not appear to predict reconstructive success and healing, with many flaps "self-adjusting" with time.

Impact of Concurrent Chronic Rhinosinusitis on Complication Rates after Endonasal Endoscopic Skull Base Surgery: A Single-Center Experience.

Objectives Preoperative planning of endoscopic skull base surgery (ESBS) is essential. The safety of performing surgery before managing sinus pathologies including concurrent chronic rhinosinusitis (CRS) in patients undergoing ESBS has been questioned. The current study aimed to evaluate and compare the complication rates between patients with and without CRS undergoing ESBS. Design This is a retrospective study. Setting Present study was conducted at tertiary referral center. Participants We included all patients who underwent ESBS between March 2015 and March 2021. However, patients who had surgical revision for remnant tumor, primary sinonasal tumor excision, and cerebrospinal fluid (CSF) leakage repair were excluded. The presence of concurrent CRS was determined according to the European Position Paper on Rhinosinusitis and Nasal Polyps 2020 (EPOS 2020) criteria by reviewing electronic charts about the preoperative clinical assessment and CT scan images of the paranasal sinuses. Then, the incidence rates of postoperative meningitis, CSF leakage, and surgical site infection were compared between patients with and without concurrent CRS undergoing ESBS. Main Outcome Measures Postoperative complication rates in patients underwent ESBS with and without CRS. Results From a total of 130 ESBS cases, 99 patients were included in this study. Among them, 24 had concurrent CRS. One patient presented with postoperative meningitis, one with CSF leakage, and two with surgical site infections. The incidence rate of postoperative meningitis, CSF leakage, and surgical site infection did not significantly differ between patients with and without concurrent CRS. Conclusion Concurrent CRS is not a contraindication for ESBS. Moreover, simultaneous endoscopic sinus surgery can safely be performed without additional morbidity in ESBS.

Lumber drain morbidity in endonasal endoscopic skull base surgery

The purpose of this study is to describe the morbidity in patients undergoing endoscopic skull base surgery (ESBS) with and without intra-operative lumbar drain (LD) placement. A retrospective review of all patients undergoing ESBS from July 2018 to August 2020 at a tertiary academic skull base surgery program was conducted. Those with LD placement for aiding in suprasellar dissection and/or for CSF diversion following skull base repair were included.LD-related medical and technical complications were combined as composite outcomes to assess overall event rates in those with and without LD. 104 patients were included. Of the 104 participants, 64 (61.5%) had LD placed. Of these 64, 1 (0.96%) and 2 (1.9%) experienced postoperative medical (hypophysitis) and related technical (2 blood patches) complications, respectively. There was one case of postoperative CSF leak (in LD group) and no cases of DVT/PE or meningitis. LD use was not associated with increased risk of any complication (p = 0.165) compared to those without LD. There were no significant differences in rates of postoperative epistaxis (p = 0.427), readmission (p = 0.629), or reoperation (p = 0.165) between groups. Female sex was the only predictor of increased overall complication rates in patients with LD (OR, 1.122, 95% CI, 1.010–1.247, p = 0.032). Our findings suggest judicious use of a LD in endoscopic skull base surgery within a reasonable time does not increase the incidence of overall medical or technical complications, readmission, and reoperation.

Visual deterioration after endonasal endoscopic skull base surgery: causes, treatments, and outcomes.

Visual deterioration after endoscopic endonasal transsphenoidal surgery (EETS) for sellar and parasellar masses is a rare but serious complication caused by either compressive or ischemic mechanisms. Timely diagnosis and intervention may restore vision if instituted appropriately. The associated risk factors and their relation to the success of intervention are not well understood. The authors examined a series of 1200 consecutive EETS cases performed by the senior author at Weill Cornell/NewYork-Presbyterian Hospital from 2010 to 2020. Cases with postoperative visual deterioration were identified. Pre- and postoperative clinical data, mechanism of visual decline, latency to intervention, and long-term visual outcome were retrospectively collected and analyzed with appropriate statistical methods. Twenty-one patients (1.75%) complained of early postoperative visual deterioration. The most common pathology associated with postoperative visual loss was craniopharyngioma (7.69%), followed by meningioma (5.43%) and then pituitary adenoma (1.94%). Timely intervention restored vision in 81% of patients for a 0.33% rate of permanent visual deterioration. Average time to visual deterioration was 28.8 hours, and over 70% of patients experienced vision loss within the first 13 hours. Compressive etiology (n = 11), consisting of either hematoma (n = 8) or graft displacement (n = 3), occurred 7.3 hours and 70.3 hours after surgery, respectively, and was more common in adenomas. Acute postoperative visual deterioration was more common in firm closures (4.78%) compared with soft closures (1.03%; p = 0.0006). Ischemic etiology (n = 10) occurred 10.3 hours after surgery and was more common with craniopharyngiomas and meningiomas (p = 0.08). Sixteen patients (76.2%) underwent early reoperation to explore and decompress the optic apparatus. Vision was restored to baseline after reoperation in all 11 compressive cases, whereas 6/10 ischemic cases improved with supplemental oxygen and hypervolemic hypertensive therapy (p = 0.02). Fluid expansion from 8 to 16 hours (p = 0.034) and systolic blood pressure elevation from 32 to 48 hours (p = 0.05) after surgery were significantly higher in those ischemic patients who recovered some vision compared with those with persistent visual deficits. Visual deterioration after EETS is a rare event but can be effectively treated if acted upon appropriately and in a timely fashion. Compressive etiology is reversible with early reoperation. Ischemic etiology can be successfully treated in roughly half of cases with supplemental oxygen and hypertensive hypervolemic therapy but may result in permanent visual deterioration if not instituted appropriately or if delayed with unnecessary exploratory surgery.

Adjunctive Middle Turbinectomy for Endoscopic Medial Orbital Wall - Thyroid Eye Disease Decompression.

Introduction Middle turbinate resection (MTR) is commonly performed during endonasal endoscopic sinus and skull base surgery. Objective The purpose of this study was to characterize the additional orbital soft-tissue volume expansion during endoscopic medial orbital wall decompression with adjunctive MTR. Methods A retrospective review of patients who underwent endoscopic medial wall decompression with MTR was performed. The imaging software AW (GE Healthcare, Chicago, IL, USA) was used to overlay pre and postoperative orbital computed tomography (CT) images to visualize the preoperative position of the middle turbinate and the postoperative orbital soft tissue in the ethmoid bed. The imaging software Vitrea (Vital Images Inc., Minnetonka, MN, USA) was used to manually segment postoperative scans to determine the volume of orbital tissue which had filled the space previously occupied by the middle turbinate or medial to it. Results Nine orbits from 5 patients were included in this study; all patients were female with a history of hyperthyroidism. The average age was 55.6 years (range 32-74). Of the 9 orbits, 7 (78%) had orbital soft tissue within the space of the resected middle turbinate postoperatively. The average volume of orbital tissue within or medial to this space was 0.83 +/- 0.67 cc. No patients had any postoperative complications. Conclusions In this patient cohort, adjunctive middle turbinate resection for endoscopic medial orbital wall decompression added ∼ 0.83 cc of volume for orbital soft tissue after medial wall decompression. Middle turbinate resection is a useful adjunct to the orbital surgeon's armamentarium to augment the results of a medial orbital decompression for select patients.

Experience and modification of skull base reconstruction results in lower complications rates

To investigate the efficacy of nasal septum bone flap combined with vascularized pedicle nasoseptal flap (VP-NSF) in the treatment of high-flow cerebrospinal fluid (CSF) leakage in the endonasal endoscopic skull base surgery. A total of 156 patients in group A used a multi-layer skull base reconstruction method of fat-absorbable artificial dura mater- fascia lata-VP-NSF, and were treated with drainage of the lumbar cistern after surgery, in addition, a total of 94 patients in group B used a multi-layer skull base reconstruction method of fat-absorbable artificial dura mater-nasal septal bone flap-VP-NSF, and no lumbar cistern drainage was performed after surgery. Analyzed and compared the differences of postoperative cerebrospinal fluid rhinorrhea, intracranial infection, re-repair, average bed rest time, pulmonary infection and deep venous thrombosis of lower extremities were analyzed and compared in the two groups. In group A, 11 cases of cerebrospinal fluid rhinorrhea occurred after operation. In addition, 15 cases developed intracranial infection. During this period, there were 20 cases of pulmonary infection and 3 cases of deep venous thrombosis of lower extremities. In group B, there were 1 case of cerebrospinal fluid rhinorrhea (P < 0.05), 2 cases of intracranial infection (P < 0.05), 2 cases of pulmonary infection (P < 0.05), and 0 case of deep venous thrombosis of lower extremities (P > 0.05). Nasal septum bone flap combined with VP-NSF is effective in the treatment of high-flow CSF leaks in the endonasal endoscopic skull base surgery, which can avoid postoperative lumbar cistern drainage and is worth popularizing.

Endoscopic Anatomy and a Safe Surgical Corridor to the Anterior Skull Base

We describe the possibility to create precise preoperative planning for endonasal endoscopic approaches to the anterior skull base by overlapping endoscopic and radiologic anatomy. The important anatomic structures were marked. Morphometric measurements between these anatomic landmarks were performed endoscopically and compared with radiologic measurements of the same areas to ensure result compatibility. Seven cadaver heads injected intravascularly with colored silicone were used for this study. Thin-section brain and paranasal sinus computed tomography scans were obtained on all cadavers. Using 0-degree rigid endoscopes and endonasal endoscopic surgical instruments, the anterior skull base was examined binostrally in all cadavers. Bilateral middle turbinates were identified and preserved. Next, an inferior uncinectomy and middle meatal antrostomy were performed. After performing a frontal antrostomy, bilateral anterior and posterior ethmoidal cells were opened and the skull base was identified and followed to the posterior wall of the frontal sinus. A transnasal transethmoidal sphenoidotomy was done with full exposure to the entire anterior skull base. The anatomic landmarks for endonasal endoscopic skull base approaches were distinguished and measurements were made. The anterior skull base was divided into 3 compartments: anterior (area between the posterior inferior border of the frontal sinus and the course of anterior ethmoidal artery), middle (area between the course of the anterior ethmoidal artery and that of the posterior ethmoidal artery [PEA]), and posterior (area between the course of the PEA and the attachment point of the anterior border of the sphenoid sinus to the skull base) compartments. The distances between important anatomic markers and endoscopic depth measurements of this area were measured. During endonasal endoscopic anterior skull base surgery, the area between the anterior border of the sphenoid sinus and PEA artery was safe as the first dissection zone. Preoperative radiologic width and depth measurements facilitate orientation to the endoscopic anatomy during surgery and help predict the endonasal surgical corridor anatomy preoperatively.

Risk factors for postoperative CSF leakage after endonasal endoscopic skull base surgery: a meta-analysis and systematic review.

Cerebrospinal fluid (CSF) leakage is a complication that any surgeon working in the field of skull base surgery does not wish to encounter. The surgical approach to the skull base often varies, and the various sizes and locations of skull base lesions make it difficult to determine the cause of CSF leakage. However, it is useful to investigate which factors contribute to postopera- tive CSF leakage. Related studies were identified by searching the following databases: PubMed/Medline, Embase, and Web of Sciences through December 2019. Random-effects models were used to calculate odds ratios (ORs) and 95% confidence intervals (CIs). The Newcastle-Ottawa scale was used to evaluate the quality of observational studies. Our search yielded 56 retrospective cohort studies involving a total of 11,826 skull base surgical procedures. The overall rate of postoperative CSF leakage was 7.2%. The effect of obesity on postoperative CSF leakage had an OR of 1.88, and the effect of perioperative radiotherapy on postoperative CSF leakage yielded an OR of 1.87. High intraoperative CSF flow rate also had a significant OR of 2.98. On the other hand, a pedicled vascularized flap efficiently reduced the risk of postoperative CSF leakage. Defect size and the presence or absence of a lumbar drain had no effect on postoperative CSF leakage. This comprehensive quantitative assessment of postoperative CSF leakage showed that obesity, perioperative radiotherapy, and high intraoperative CSF flow rate raised the risk of CSF leakage; however, a pedicled vascularized flap can ef- fectively reduce the risk of postoperative CSF leakage.

Application of endoscopic endonasal approach in skull base surgeries: summary of 1886 cases in a single center for 10 consecutive years

BackgroundEndonasal endoscopic skull base surgery has undergone rapid technological developments and is now widely performed, but its strengths and weaknesses deserve further investigation and deliberation. This study was performed to investigate the surgical indications, complications, and technical advantages and disadvantages of endonasal endoscopic skull base surgery.MethodsThe clinical data of 1886 endoscopic endonasal skull base surgeries performed in our ward at Beijing Tiantan Hospital from June 2006 to June 2016 were retrospectively analyzed.ResultsOne thousand ninety-three (73.4%, 1490) pituitary adenomas, 54 (24.9%, 217) chordomas, 28 (80.0%, 35) craniopharyngiomas, and 15 (83.3%, 18) meningiomas underwent total resection. Two patients died postoperatively, both having pituitary adenomas. Other postoperative complications included olfactory disorders (n = 226, 11.9%), postoperative cerebrospinal fluid leakage (n = 78, 4.1%), hypopituitarism (n = 74, 3.9%), diabetes insipidus (n = 64, 3.4%), intracranial infection (n = 36, 1.9%), epistaxis (n = 24, 1.3%), vascular injury (n = 8, 0.4%), optic nerve injury (n = 8, 0.4%), and oculomotor movement impairment (n = 4, 0.2%). In total, 1517 (80.4%) patients were followed up for 6 to 126 months (average, 42.5 months) postoperatively. A total of 196 (13.2%) pituitary adenomas and 13 (37.1%) craniopharyngiomas recurred but no meningiomas recurred. Chordomas recurred in 97 (44.7%) patients, in whom 5-year survival rate was 65%.ConclusionEndoscopic surgery is an innovative surgical technique and the first choice for most midline extradural lesions such as chordomas, and an excellent choice for pituitary adenomas. It probably will be a good technique for many kinds of craniopharyngiomas and a common technique for most of skull base meningiomas, so the surgical indications of these cases should be chosen carefully to make good use of its respective advantages.

Endoscopic Endonasal Trans-Sphenoidal and Skull Base Surgeries in Aseer Central Hospital, Sothern Saudi Arabia

Endoscopic Endonasal Trans-Sphenoidal and Skull Base Surgeries in Aseer Central Hospital, Sothern Saudi Arabia

Endonasal Endoscopic Surgery for Pediatric Sellar and Suprasellar Lesions: A Systematic Review and Meta-analysis.

The advent of endonasal endoscopic skull base surgery (ESBS) has redefined the management of pediatric sellar and suprasellar lesions. To date, the outcomes of these procedures have not been systematically reviewed. This study performed a systematic review with meta-analysis of surgical outcomes for pediatric patients undergoing ESBS for sellar and suprasellar lesions. PubMed (National Library of Medicine, National Institutes of Health), Scopus (Elsevier), and Cochrane Library (Wiley). Articles reporting on pediatric patients undergoing ESBS for craniopharyngiomas, pituitary adenomas, and Rathke's cleft cysts were reviewed. The primary outcome was postoperative cerebrospinal fluid (CSF) leak. Secondary outcomes included endocrine, visual, and other complications. Twenty-five articles reporting on 554 patients were included. Overall postoperative CSF leak rate was 8.6%, with tumor-specific rates of 10.6% in craniopharyngiomas, 6.5% in pituitary adenomas, and 7.2% in Rathke's cleft cysts (P > .05). Older studies demonstrate higher postoperative CSF leak rates as compared with more recent studies (12.5% vs 6.1%, P = .0082). Younger children (8.9-12.6 years old) experienced a higher rate of postoperative CSF leaks as compared with older children (13.0-16.6 years old; 12.9% vs 4.9%, P = .0016). Additional postoperative complications included diabetes insipidus (26.7%), hypopituitarism (46.6%), visual deficits (2.6%), meningitis (3.4%), and weight gain (3.4%). ESBS for pediatric sellar and suprasellar lesions is overall an effective management approach with an increasingly favorable risk-benefit profile. Younger children may be more susceptible to postoperative CSF leak as compared with older pediatric patients. Tumor type does not appear to be an independent risk factor for postoperative CSF leak in this population.

SURG-22. CUSHING’S DISEASE: A DIFFICULT TO TREAT NEURO-ONCOLOGICAL CONDITION

Abstract BACKGROUND Cushing disease (CD) comprises a spectrum of clinical manifestations secondary to hypercortisolism due to ACTH-secreting pituitary adenoma. Transsphenoidal adenomectomy remains the standard treatment. Because of the significant rate of recurrence or persistence of CD, it is of interest to determine factors that may correlate with long-term outcomes following surgical intervention. OBJECTIVE The objective of our study is to determine the remission rate after surgery with special emphasis on factors affecting remission. METHODS Data of all patients undergoing surgery for CD from 2009 to 2017 was analyzed retrospectively. Transphenoidal resection was the preferred treatment with a recent trend in favor of endonasal endoscopic skull base approach. Post-operative cortisol level of &lt; 2 μg/dL was taken as remission and value between 2 and 5 μg/dL as possible remission. RESULTS 104 patients operated primarily for CD were included for analysis. 47 patients underwent microscopic surgery, 55 endoscopic surgery and two were operated trans-cranially. Remission was achieved in 76.47% of patients. In univariate analysis, factors significantly associated with remission were (1) type of surgery (p=0.01); endoscopy (88.23% remission) better than microscopy (56.6% remission) (2) postoperative day-1 morning cortisol (p=0.004) and; (3) postoperative day-1 morning ACTH (p=0.015). In multivariate analysis, however only postoperative day-1 cortisol was found to be significant as predictor of remission (p=0.02). CONCLUSION Postoperative plasma cortisol level is a strong independent predictor of remission and value less than 10.7µgm/dl can be taken as cut off for predicting remission. Remission provided by endoscopy appears to be significantly better than microscopic approach.

Management of Cushing's Disease: Changing Trend from Microscopic to Endoscopic Surgery

Cushing's disease (CD) is a spectrum of clinical manifestations due to adrenocorticotropic hormone-secreting pituitary adenoma. Transsphenoidal adenomectomy remains the standard treatment. There has been a paradigm shift from microscopic to endoscopic transsphenoidal surgery in recent years. However, the efficacy of endoscopic transsphenoidal surgery has not been established. Therefore, it is of interest to determine the superiority of endoscopic transsphenoidal surgery, if any, over microscopic surgery. To assess the efficacy of endoscopic endonasal transsphenoidal surgery for the treatment of CD and to determine the factors affecting remission. Patients undergoing surgery for CD from 2009 to 2017 were analyzed retrospectively. Transsphenoidal resection was the preferred treatment, with recent trends in favor of the endonasal endoscopic skull base approach. Postoperative cortisol level of <2 μg/dL was taken as remission and value between 2 and 5 μg/dL as possible remission. In total, 104 patients operated primarily for CD were included for analysis; 47 patients underwent microscopic surgery, 55 endoscopic surgery, and 2 were operated transcranially. Remission was achieved in 76.47% of patients. In univariate analysis, factors significantly associated with remission were 1) type of surgery (P= 0.01); remission in endoscopy surgery (88.23%) is better than microscopy (56.6%); 2) postoperative day 1 morning cortisol (P= 0.004); and 3) postoperative day 1 morning ACTH (P=0.015). In multivariate analysis, only postoperative day 1 cortisol was found to be significant predictor of remission (P= 0.02). Postoperative plasma cortisol level is a strong independent predictor of remission. Remission provided by endoscopy is significantly better than the microscopic approach.

Postoperative Continuous Positive Airway Pressure Use and Nasal Saline Rinses After Endonasal Endoscopic Skull Base Surgery in Patients With Obstructive Sleep Apnea: A Practice Pattern Survey.

Endoscopic skull base surgery continues to evolve in its indications, techniques, instrumentation, and postoperative care. As surgery of the skull base will often violate dura, intraoperative and postoperative cerebrospinal fluid (CSF) leak is not uncommon and represents a potential conduit for air and bacterial contamination. Patients with obstructive sleep apnea (OSA) requiring continuous positive airway pressure (CPAP) therapy undergoing skull base surgery represent a challenging group. However, there appears to be a paucity of consensus regarding the postoperative management of this patient population. The objective of this study is to examine practice patterns and expert opinion on the use of postoperative CPAP and nasal saline in patients with OSA. A 14-item survey was generated by consensus among expert authors and distributed online to members of the North American Skull Base society and other international skull base community members. Data were analyzed for median, mean, and standard deviation variables. Subgroup analysis was completed between surgeons from different geographical locations and operative experience. SPSS22 was utilized for all complex statistical analysis and figures. Seventy-one responses were collected from skull base surgeons. In patients with OSA, respondents would resume patients' CPAP therapy after a mean of 10.1 days (median, 7; standard deviation [SD], 10.2), without a CSF leak. In the presence of a small CSF leak, the mean duration would increase to 14.3 days (median, 14; SD, 9.8) and to 20.7 days (median, 21; SD, 11.8) in the presence of a larger leak. A surgeon's choice to attribute the relationship between delaying the start of nasal saline and CPAP after the endoscopic skull base surgery with progressively more challenging skull base repair was found to be statistically significant ( P < .001). Saline and CPAP therapies are initiated after the endoscopic skull base surgical repairs by surgeons at an increasing temporal delay in relation to the degree and complexity of the skull base defect repaired.

The Validity of Training Endoscopic Sinus and Skull Base Surgery Techniques on the Experimental Head Model.

The aim of this study was to better understand the usual learning curve in acquiring endonasal endoscopic sinus and skull base surgery (ESSBS) techniques during the novice training on the lamb's head model. Ten novices were asked to perform 10 bilateral dissections on the particular lamb's head each. The dissections were uniform, consisted of 10 well-defined steps, beginning from the simple removal of the inferior turbinate, and ending with more complicated procedures like cerebrospinal fluid leak repair, Draf 3 procedure for the frontal sinus and elevation of the nasal septal flap. The dissections have been supervised by experienced surgeons. A set of standard ESSBS instruments and 0° and 45° endoscopes have been used under the navigational system. The time required to complete each step has been measured in minutes. In general and quite expectedly, time rates have been obviously lowering as the number of the dissections performed has been growing in each of the participants. Training of the endonasal ESSBS techniques on the lamb's head proved to be useful for novices in getting basic surgical skills in the field. Because of the high degree of anatomic similarity and high level of the anatomic dimensions congruency between the lamb's head and human head (sheep's head has bigger dimensions!) it proved to be an essential preparation for the human cadaveric dissection. The median values of the time rates having been needed to complete the particular of the 10 steps in the last novices' dissections could be accepted as an orientation, just suggesting that once the time needed to complete 1 of the 10 steps has been and achieved by the particular novice, this could be an approximate sign of the maturity for the exercises on human cadaver head.

Objective Validation of Perfusion-Based Human Live Cadaveric Simulation Training Model for Management of Internal Carotid Artery Injury in Endoscopic Endonasal Sinus and Skull Base Surgery

Objective Validation of Perfusion-Based Human Live Cadaveric Simulation Training Model for Management of Internal Carotid Artery Injury in Endoscopic Endonasal Sinus and Skull Base Surgery

Postoperative tension pneumocephalus resulting in encephalopathy and seizure activity: Answer

A.CSF leakage Tension pneumocephalus—symptomatic intracranial air, confirmed by head CT—is a rare phenomenon that has been reported in multiple settings (e.g., trauma, infection) [[1]Schirmer C.M. Heilman C.B. Bhardwaj A. Pneumocephalus: case illustrations and review.Neurocrit Care. 2010; 13: 152-158Crossref PubMed Scopus (123) Google Scholar]. Additionally, air accumulation has been linked to post-operative CSF leakage [[2]Banu M.A. Szentirmai O. Mascarenhas L. et al.Pneumocephalus patterns following endonasal endoscopic skull base surgery as predictors of postoperative CSF leaks.J Neurosurg. 2014; 121: 961-975Crossref PubMed Scopus (42) Google Scholar]. A few cases have attributed seizures to pneumocephalus, but corresponding EEG findings have not been reported [[3]Lam K.K. Prasad A. Fehlings M.G. Venkatraghavan L. Pneumocephalus: an unusual case of postoperative seizure after intradural spine surgery.Can J Anaesth. 2014; 61: 969-970Crossref PubMed Scopus (9) Google Scholar]. CSF leakage after supratentorial tumor resection is often due to hydrocephalus. As this patient's preoperative and postoperative imaging did not show gross hydrocephalus, increased intracranial pressure secondary to edema combined with intraoperative involvement of the temporal horn of the lateral ventricle are most likely responsible for CSF leakage, which then permitted one-way entry and accumulation of air (“ball-valve” mechanism), eventually causing symptoms. The most likely explanation for new onset persistent right-sided weakness three days following a clinical seizure is recurrent left hemisphere-onset focal subclinical electrographic seizures. The weakness cannot be explained by Todd’s paresis as this does not correlate with ictal activity on EEG. This patient’s EEG was consistent with focal non-convulsive status epilepticus (NCSE), with electrographic seizures emerging from cerebral regions of complex structural pathology secondary to tumor resection. The patient continued to be in NCSE despite receiving adequate anticonvulsive therapy. Following shunt placement, the patient improved cognitively, and right-sided weakness/sensation and NCSE resolved, suggesting that mass effect of pneumocephalus contributed to patient’s clinical course. This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. The authors report no disclosures. Postoperative tension pneumocephalus resulting in encephalopathy and seizure activity: QuestionJournal of Clinical NeuroscienceVol. 47PreviewA 46-year-old man underwent subtotal resection of a 2.8 × 2.7-cm left temporoparietal glioblastoma (Fig. 1A-B). Levetiracetam 500 mg BID was started prophylactically for seizures. He was discharged home in good condition. Five days later and following staple removal, he presented with headache, gait ataxia, and confusion. On exam, he was disoriented but showed no motor or sensory deficits. Head CT revealed extensive intracranial air with a 4-mm midline shift (Fig. 1C-D). Two subgaleal angiocatheters were placed to relieve air pressure. Full-Text PDF

Analysis of the venous channel within the clivus using multidetector computed tomography digital subtraction venography.

Although neuroradiologists and skull base neurosurgeons are aware of the existence of veins within the clivus, such vessels have seldom been described in the literature. The aim of the present study is to elucidate the detailed venous structure of the clivus. Computed tomography digital subtraction venography (CT-DSV) images of 50 unruptured aneurysm cases were examined retrospectively. Eighteen emissary veins were identified in 14 (28.0%) cases. A half of the emissary veins connected the inferior petrosal sinus with the inferior petro-occipital vein (IPOV) in the middle clivus. The clival diploic vein (CDV) was identified in 14.0% of cases, 42.9% of which had the clivus of the presellar type. The CDV was connected to the posterior intercavernous sinus or the rostral end of the basilar plexus superiorly, and was connected to the IPOV, anterior condylar vein, marginal sinus, or the anterior condylar confluence. The CDV provides collateral channels between the cavernous sinus and the internal jugular vein and the inferior petrosal sinus and the IPOV. Understanding of the emissary veins in the clivus and the CDV is valuable for skull base surgery, especially for endonasal endoscopic skull base procedures.

Postoperative Findings in Endoscopic Endonasal Surgery of The Skull Base

Since the introduction of endonasal endoscopic skull base surgery the exclusive purpose in the management of skull base neoplasms has been to increase survival rates Recently given the improved prognosis achieved more attention has been focused on the functional outcomes such as nasal symptoms and quality of life QOL The purpose of this review is to assess the functional outcomes after endonasal endoscopic skull base surgery