Endoscopic Endonasal Transsphenoidal Resection of Pituitary Adenomas in Patients Presenting With Monocular Blindness.

BACKGROUND AND OBJECTIVES: Suprasellar tumors, particularly pituitary adenomas (PAs), commonly present with visual decline, and the endoscopic endonasal transsphenoidal approach (EETA) is the primary management for optic apparatus decompression. Patients presenting with complete preoperative monocular blindness comprise a high-risk subgroup, given concern for complete blindness. This retrospective cohort study evaluates outcomes after EETA for patients with PA presenting with monocular blindness. METHODS: Retrospective analysis of all EETA cases at our institution from June 2012 to August 2023 was performed. Inclusion criteria included adults with confirmed PA and complete monocular blindness, defined as no light perception, and a relative afferent pupillary defect secondary to tumor mass effect. RESULTS: Our cohort includes 15 patients (9 males, 6 females), comprising 2.4% of the overall PA cohort screened. The mean tumor diameter was 3.8 cm, with 6 being giant PAs (>4 cm). The mean duration of preoperative monocular blindness was 568 days. Additional symptoms included contralateral visual field defects (n = 11) and headaches (n = 10). Two patients presented with subacute PA apoplexy. Gross total resection was achieved in 46% of patients, reflecting tumor size and invasiveness. Postoperatively, 2 patients experienced improvement in their effectively blind eye and 2 had improved visual fields of the contralateral eye. Those with improvements were operated within 10 days of presentation, and no patients experienced worsened vision. CONCLUSION: This is the first series of EETA outcomes in patients with higher-risk PA with monocular blindness on presentation. In these extensive lesions, vision remained stable for most without further decline and improvement from monocular blindness was observed in a small subset of patients with no light perception and relative afferent pupillary defect. Timing from vision loss to surgical intervention seemed to be associated with improvement. From a surgical perspective, caution is warranted to protect remaining vision and we conclude that EETA is safe in the management of these patients.

Efficacy of a RADA-16 peptide hydrogel versus chitosan-based polymer in improving patient comfort during postoperative debridement: A randomized controlled trial.

BACKGROUND: Bioresorbable nasal packing is associated with a decreased incidence of adhesions and bleeding postoperatively after endoscopic sinus surgery (ESS). However, discomfort during postoperative debridement is still a major area of concern for patients. Our objective was to compare the efficacy of a peptide hydrogel to that of a chitosan-based polymer in reducing pain during debridement after ESS. METHODS: A prospective, multicenter, randomized, blinded trial was conducted in adults undergoing bilateral total ethmoidectomy for chronic rhinosinusitis. Participants served as their own controls with each subject receiving the hydrogel in a randomized ethmoid cavity and chitosan-based polymer in the contralateral ethmoid cavity. Participants were evaluated at 1, 4, and 12 weeks postoperatively. Pain during debridement as well as endoscopic evaluation of mucosal healing and hemostasis were measured. RESULTS: Thirty patients who underwent ESS were included in this trial. During the week 1 postoperative debridement, patients reported significantly less pain on the hydrogel-treated side compared to the chitosan-based polymer-treated side. There were no significant differences in bleeding severity, Lund-Kennedy scores, debridement time, or need for further intervention between the two groups. CONCLUSION: This study demonstrated the efficacy of a peptide hydrogel in minimizing pain during postoperative debridement.

Ectopic Olfactory Neuroblastoma: Systematic Review of a Rare Clinical Entity among Sinonasal Tumors.

Objectives Ectopic olfactory neuroblastoma is an uncommon manifestation of an already rare neoplasm. We aimed to systematically review the literature for cases of ectopic olfactory neuroblastoma to better characterize this rare disease entity and to present two new case reports. Methods A search of the PubMed and Embase databases was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines to identify English-language articles reporting cases of ectopic olfactory neuroblastoma, published from 1955 through November 2021. Results Sixty-six cases of ectopic olfactory neuroblastoma were identified in 62 articles including the current review. Ectopic olfactory neuroblastoma arose in a wide age range (2-89 years) without significant sex predilection. It occurred most commonly in the ethmoid (25%), maxillary (25%), and sphenoid (16%) sinuses. Seventy-three percent of cases presented with low Hyams grade (I and II). The most common symptoms were nasal obstruction (32%) and epistaxis (32%). Paraneoplastic syndromes were observed in 27% of patients. The most common treatment was surgical resection followed by adjuvant radiotherapy. Overall, 76% of all patients were disease-free at the time of last follow-up. Locoregional recurrences and distant metastases were found in 19 and 5% of cases, respectively. Conclusion This systematic review describes previously reported cases of ectopic olfactory neuroblastoma, a disease entity with poorly understood characteristics. Physicians should consider olfactory neuroblastoma in the differential diagnosis for sinonasal masses, as their ectopic presentation may present considerable diagnostic and therapeutic difficulties. Patients with olfactory neuroblastoma may benefit from long-term follow-up and routine endoscopic examinations for surveillance of ectopic recurrences.

Radiofrequency Neurolysis of the Posterior Nasal Nerve: A Systematic Review and Meta-Analysis.

OBJECTIVE: Temperature-controlled radiofrequency neurolysis of the posterior nasal nerve (PNN) has been approved for use since 2020. This review synthesized the published data to assess its efficacy for treatment of chronic rhinitis. DATA SOURCES: Pubmed/Medline, Embase, Scopus, Web of Science. REVIEW METHODS: A systematic search was conducted with no restrictions on publication years in April 2023. RCTs and prospective investigations that reported the reflective Total Nasal Symptom Score (rTNSS) outcome of radiofrequency neurolysis as a single procedure in chronic rhinitis patients were included. Pooled estimates for change in rTNSS from baseline at 3 months and responder rates (≥30% reduction in baseline rTNSS) at 3 and 6 months were obtained. Other outcomes, such as postnasal drip and cough scores, quality of life (QoL) measures, and adverse events were included for qualitative review. RESULTS: Five studies were included in the systematic review, of which four were included in the meta-analysis. A total of 284 participants underwent treatment. The pooled change in rTNSS score at 3 months was -4.28 (95% CI, -5.10 to -3.46). The pooled responder rate at 3 months was 77.11% (95% CI, 68.21%-86.01%) and at 6 months 80.80% (95% CI, 70.85%-90.76%). Postnasal drip and cough scores and QoL also improved significantly at follow up. A total of 36 adverse events were reported in 21 (7.4%) patients. CONCLUSIONS: The findings from this review suggest that temperature-controlled radiofrequency neurolysis of the PNN is effective at treating chronic rhinitis symptoms and that it has an overall favorable safety profile. Laryngoscope, 134:507-516, 2024.

Gender-Specific Differences in Preoperative Concerns in Patients Undergoing Endoscopic Sinus Surgery for Chronic Rhinosinusitis.

OBJECTIVES: Among patients with chronic rhinosinusitis (CRS), gender differences in epidemiology as well as quality of life have been reported. However, whether gender differences in endoscopic sinus surgery (ESS) preoperative concerns exist is unclear. METHODS: CRS patients undergoing ESS at 3 tertiary care centers in Los Angeles completed the validated Western Surgical Concern Inventory - ESS assessing ESS preoperative concerns. RESULTS: Of the 75 patients included, female patients expressed greater concern than male patients in regard to nasal packing, undergoing anesthesia, impact of surgery on daily activities, and pain and discomfort following surgery. CONCLUSION: This study suggests there are gender differences in ESS preoperative concerns and otolaryngologists should be aware of these possible concerns during preoperative discussions.

Association of ethnicity and time to surgery among patients with chronic rhinosinusitis.

Objectives: Determine factors associated with delayed endoscopic sinus surgery (ESS) in patients with chronic rhinosinusitis (CRS). Methods: This is a retrospective cohort study conducted at a tertiary care academic center. Patients were included in the study if they were at least 18 years old and underwent surgery for CRS. Electronic medical records were retrospectively reviewed to collect demographic and clinical data. Patients with CRS secondary to another pathology such as malignancy were excluded. Multiple linear regression was performed to determine factors associated with the number of days between a patient's preoperative consultation and the date of surgery. Results: A total of 103 patients with a mean age of 46.6 ± 16.8 years were included in the analysis; 51.5% of patients were females, 46.6% identified as White, and 29.1% identified as Hispanic. The majority of patients (67.0%) had preferred provider organization health insurance; 43.7% of patients had nasal polyps, 70.9% had a deviated nasal septum, and the mean preoperative Sinonasal Outcomes Test-22 (SNOT-22) score was 41.0 ± 23.8. The mean time to surgery after the final preoperative visit was 71.7 days ± 65.6 days. Hispanic ethnicity was associated with increased time to surgery (p < .05) when controlling for other variables. No other variables were associated with time to surgery on multivariate analysis. Conclusion: Hispanic ethnicity may be an independent predictor of increased time to sinus surgery independent of disease severity and other demographic variables. Level of Evidence: 2b.

Optical Coherence Tomography as a Tool for Imaging the Sinonasal Mucosa in Patients: A Systematic Review.

Objectives: To summarize the current applications and potential uses of optical coherence tomography (OCT), a noninvasive imaging modality that uses near-infrared light to produce cross-sectional, high-resolution images of biologic tissues, for evaluating the sinonasal mucosa in patients. Methods: Original articles utilizing OCT to image the sinonasal mucosa in patients were identified from the PubMed, Embase, Cochrane Library, Web of Science, and Scopus databases using the search phrase: "Optical Coherence Tomography" AND (sinonasal OR intranasal OR sinus OR nose OR sinusitis OR rhinitis OR olfactory). Strength of evidence, quality of evidence, and risk of bias were measured using validated scales. Study results were qualitatively assessed. Results: Out of 1662 original records identified through database searching, 9 studies were included in the systematic review. Levels of evidence ranged from III to IV and quality of evidence ranged from moderate to very low. Endoscopic OCT systems as well as OCT systems integrated with surgical microscopes were described in the literature. Applications of OCT for imaging the sinonasal mucosa included identifying morphological patterns unique to individual diseases, detecting mucosal structural changes after medical therapies and procedures, and evaluating mucociliary clearance. Conclusions: Most studies investigating OCT imaging of the sinonasal mucosa featured small sample sizes and lacked control groups. While OCT imaging could be a useful adjunct for diagnosing sinonasal disorders and monitoring response to treatment in the future, additional high-quality studies are necessary to determine if the use of OCT imaging can lead to improved diagnostic accuracy and health outcomes for patients with sinonasal pathologies.

An Endoscopic Endonasal Attempt at Pediatric Meningoencephalocele Repair.

Meningoencephalocele is an abnormal skull base protrusion of fluid, brain tissue, and meninges that can lead to nasal obstruction, meningitis, and Cerebrospinal Fluid (CSF) rhinorrhea. This condition can be managed operatively through an open craniotomy or a less invasive endoscopic approach. Here, we report a case of an 18-month-old female who presented with a meningoencephalocele that was part of the Sakoda complex, a rare neurosurgical phenomenon consisting of meningoencephalocele, agenesis of the corpus callosum, and cleft lip/palate. The patient was initially treated with the endoscopic transsphenoidal approach with subsequent open craniotomy.

Anatomic Considerations Guiding Single Versus Multiportal Endoscopic Approaches for Resection of Juvenile Nasopharyngeal Angiofibroma: Cases Series With Graded Multicorridor Resections.

BACKGROUND: Juvenile nasopharyngeal angiofibromas (JNAs) are characterized by expansive and destructive growth, often invading the midline/paranasal sinuses, pterygopalatine fossa, and infratemporal fossa and can extend into the orbit, cavernous sinus, or intracranially. OBJECTIVE: To evaluete the major benefits of the extended endoscopic endonasal approach (EEA) for JNA resection as compared with more traditional and invasive transpalatal and transfacial approaches. When JNAs extend into lateral anatomic compartments, the optimal operative trajectory often requires additional approach strategies or surgical staging. METHODS: We retrospectively reviewed 8 cases of large JNAs arising in symptomatic adolescent boys (University of Pittsburgh Medical Center Stages II, III, and V) and discuss anatomic and tumor considerations guiding the decision of a pure EEA vs combined EEA and sublabial transmaxillary approach (Caldwell-Luc). RESULTS: A pure extended EEA was used in 6 JNA cases (UPMC Stages II-III); a multiportal EEA + Caldwell-Luc maxillotomy was used in 2 cases. One of the 2 patients (UPMC Stage V) previously treated with multiportal EEA + Caldwell-Luc maxillotomy underwent staged left temporal/transzygomatic craniotomy, obtaining gross total resection. Seven patients ultimately underwent complete removal without recurrence. One patient with a small residual JNA (UPMC II) underwent stereotactic radiosurgery without progression to date. CONCLUSION: JNAs with lateral extension into the infratemporal fossa often benefited from additional lateral exposure using a Caldwell-Luc maxillotomy. Cases with significant skull base and/or dural involvement may undergo staged surgical treatment; temporalis + transzygomatic craniotomy is often useful for second-stage approaches for residual tumor in these lateral infratemporal or intracranial regions. SRS should be considered for residual tumor if additional surgery is not warranted.

Unplanned 30-Day ER Visit Rate and Factors Associated With ER Visits After Ambulatory Sinus Surgery.

BACKGROUND: Emergency room (ER) visits after surgery can be inconvenient and costly to the patient and the healthcare system. Estimates of the 30-day ER visit rate following ambulatory sinus procedures and their risk factors are largely unknown in the literature. OBJECTIVE: To determine the 30-day postoperative ER visit rate following ambulatory sinus procedures and the causes and risk factors associated with ER visits. METHODS: This is a retrospective, cohort study using data from the State Ambulatory Surgery and Services Databases (SASD) and the State Emergency Department Databases (SEDD) for California, New York, and Florida in 2019. We identified adult (18 years old) patients with chronic rhinosinusitis who underwent ambulatory sinus procedures from the SASD. Cases were linked to the SEDD to identify ER visits occurring within 30 days after the procedure. Logistic regression models were used to identify patient- and procedure-related risk factors associated with the 30-day postoperative ER visit. RESULTS: Among the 23 239 patients, the 30-day postoperative ER visit rate was 3.9%. The most common reason for ER visit was bleeding (32.7%). A total of 56.9% of the ER visits occurred within the first week. In the multivariate analysis, factors associated with ER visits included Medicare (odds ratio [OR] 1.29 [1.09-1.52], P = .003), Medicaid (OR 2.06 [1.69-2.51], P < .001), self-pay/no insurance (OR 1.44 [1.03-2.00], P = .031), chronic kidney disease/end-stage renal disease (OR 1.63 [1.06-2.51], P = .027), chronic pain/opioid use (OR 2.70 [1.02-7.11], P = .045), and a disposition other than home (OR 12.61 [8.34-19.06], P < .001). CONCLUSION: The most common reason for ER visit after ambulatory sinus procedures was bleeding. An increased ER visit rate was associated with certain demographic factors and medical comorbidities but not with procedure characteristics. This information can help us identify the patient populations who are at higher risk for ER visits to improve their postoperative recovery.

A Case of Mediastinal Emphysema Following Functional Endoscopic Sinus Surgery.

Mediastinal emphysema is an extremely rare and potentially fatal complication of endoscopic sinus surgery. The case presented involves a 73-year-old man who developed mediastinal emphysema following endoscopic sinus surgery for severe sinonasal polyposis. We describe the multiple etiologies that may have contributed to his condition including possible microtrauma at the time of intubation or during intubation, microfracture of the orbital wall/lamina papyracea, and severe hiccups.

Validation of Machine Learning-Based Automated Surgical Instrument Annotation Using Publicly Available Intraoperative Video.

BACKGROUND: Intraoperative tool movement data have been demonstrated to be clinically useful in quantifying surgical performance. However, collecting this information from intraoperative video requires laborious hand annotation. The ability to automatically annotate tools in surgical video would advance surgical data science by eliminating a time-intensive step in research. OBJECTIVE: To identify whether machine learning (ML) can automatically identify surgical instruments contained within neurosurgical video. METHODS: A ML model which automatically identifies surgical instruments in frame was developed and trained on multiple publicly available surgical video data sets with instrument location annotations. A total of 39 693 frames from 4 data sets were used (endoscopic endonasal surgery [EEA] [30 015 frames], cataract surgery [4670], laparoscopic cholecystectomy [2532], and microscope-assisted brain/spine tumor removal [2476]). A second model trained only on EEA video was also developed. Intraoperative EEA videos from YouTube were used for test data (3 videos, 1239 frames). RESULTS: The YouTube data set contained 2169 total instruments. Mean average precision (mAP) for instrument detection on the YouTube data set was 0.74. The mAP for each individual video was 0.65, 0.74, and 0.89. The second model trained only on EEA video also had an overall mAP of 0.74 (0.62, 0.84, and 0.88 for individual videos). Development costs were $130 for manual video annotation and under $100 for computation. CONCLUSION: Surgical instruments contained within endoscopic endonasal intraoperative video can be detected using a fully automated ML model. The addition of disparate surgical data sets did not improve model performance, although these data sets may improve generalizability of the model in other use cases.

Endoscopic endonasal approaches for reconstruction of traumatic anterior skull base fractures and associated cerebrospinal fistulas: patient series.

BACKGROUND: Post-traumatic cerebrospinal fluid (CSF) leaks of the anterior skull base may arise after traumatic brain injury (TBI). Onset of CSF rhinorrhea may be delayed after TBI and without prompt treatment may result in debilitating consequences. Operative repair of CSF leaks caused by anterior skull base fractures may be performed via open craniotomy or endoscopic endonasal approaches (EEAs). The authors' objective was to review their institutional experience after EEA for repair of TBI-related anterior skull base defects and CSF leaks. OBSERVATIONS: A retrospective review of prospectively collected data from a major level 1 trauma center was performed to identify patients with TBI who developed CSF rhinorrhea. Persistent or refractory post-traumatic CSF leaks and anterior skull base defects were repaired via EEA in four patients. Intrathecal fluorescein was administered before EEA in three patients (75%) to help aid identification of the fistula site(s). CSF leaks were eventually repaired in all patients, though one reoperation was required. During a mean follow-up of 8.75 months, there were no instances of recurrent CSF leakage. LESSONS: Refractory, traumatic CSF leaks may be effectively repaired via EEA using a multilayer approach and nasoseptal flap reconstruction, thereby potentially obviating the need for additional craniotomy in the post-TBI setting.

Expert surgeons and deep learning models can predict the outcome of surgical hemorrhage from 1 min of video.

Major vascular injury resulting in uncontrolled bleeding is a catastrophic and often fatal complication of minimally invasive surgery. At the outset of these events, surgeons do not know how much blood will be lost or whether they will successfully control the hemorrhage (achieve hemostasis). We evaluate the ability of a deep learning neural network (DNN) to predict hemostasis control ability using the first minute of surgical video and compare model performance with human experts viewing the same video. The publicly available SOCAL dataset contains 147 videos of attending and resident surgeons managing hemorrhage in a validated, high-fidelity cadaveric simulator. Videos are labeled with outcome and blood loss (mL). The first minute of 20 videos was shown to four, blinded, fellowship trained skull-base neurosurgery instructors, and to SOCALNet (a DNN trained on SOCAL videos). SOCALNet architecture included a convolutional network (ResNet) identifying spatial features and a recurrent network identifying temporal features (LSTM). Experts independently assessed surgeon skill, predicted outcome and blood loss (mL). Outcome and blood loss predictions were compared with SOCALNet. Expert inter-rater reliability was 0.95. Experts correctly predicted 14/20 trials (Sensitivity: 82%, Specificity: 55%, Positive Predictive Value (PPV): 69%, Negative Predictive Value (NPV): 71%). SOCALNet correctly predicted 17/20 trials (Sensitivity 100%, Specificity 66%, PPV 79%, NPV 100%) and correctly identified all successful attempts. Expert predictions of the highest and lowest skill surgeons and expert predictions reported with maximum confidence were more accurate. Experts systematically underestimated blood loss (mean error - 131 mL, RMSE 350 mL, R2 0.70) and fewer than half of expert predictions identified blood loss > 500 mL (47.5%, 19/40). SOCALNet had superior performance (mean error - 57 mL, RMSE 295 mL, R2 0.74) and detected most episodes of blood loss > 500 mL (80%, 8/10). In validation experiments, SOCALNet evaluation of a critical on-screen surgical maneuver and high/low-skill composite videos were concordant with expert evaluation. Using only the first minute of video, experts and SOCALNet can predict outcome and blood loss during surgical hemorrhage. Experts systematically underestimated blood loss, and SOCALNet had no false negatives. DNNs can provide accurate, meaningful assessments of surgical video. We call for the creation of datasets of surgical adverse events for quality improvement research.

Deep Neural Networks Can Accurately Detect Blood Loss and Hemorrhage Control Task Success From Video.

BACKGROUND: Deep neural networks (DNNs) have not been proven to detect blood loss (BL) or predict surgeon performance from video. OBJECTIVE: To train a DNN using video from cadaveric training exercises of surgeons controlling simulated internal carotid hemorrhage to predict clinically relevant outcomes. METHODS: Video was input as a series of images; deep learning networks were developed, which predicted BL and task success from images alone (automated model) and images plus human-labeled instrument annotations (semiautomated model). These models were compared against 2 reference models, which used average BL across all trials as its prediction (control 1) and a linear regression with time to hemostasis (a metric with known association with BL) as input (control 2). The root-mean-square error (RMSE) and correlation coefficients were used to compare the models; lower RMSE indicates superior performance. RESULTS: One hundred forty-three trials were used (123 for training and 20 for testing). Deep learning models outperformed controls (control 1: RMSE 489 mL, control 2: RMSE 431 mL, R2 = 0.35) at BL prediction. The automated model predicted BL with an RMSE of 358 mL (R2 = 0.4) and correctly classified outcome in 85% of trials. The RMSE and classification performance of the semiautomated model improved to 260 mL and 90%, respectively. CONCLUSION: BL and task outcome classification are important components of an automated assessment of surgical performance. DNNs can predict BL and outcome of hemorrhage control from video alone; their performance is improved with surgical instrument presence data. The generalizability of DNNs trained on hemorrhage control tasks should be investigated.

Utility of the Simulated Outcomes Following Carotid Artery Laceration Video Data Set for Machine Learning Applications.

Importance: Surgical data scientists lack video data sets that depict adverse events, which may affect model generalizability and introduce bias. Hemorrhage may be particularly challenging for computer vision-based models because blood obscures the scene. Objective: To assess the utility of the Simulated Outcomes Following Carotid Artery Laceration (SOCAL)-a publicly available surgical video data set of hemorrhage complication management with instrument annotations and task outcomes-to provide benchmarks for surgical data science techniques, including computer vision instrument detection, instrument use metrics and outcome associations, and validation of a SOCAL-trained neural network using real operative video. Design, Setting, and Participants: For this quailty improvement study, a total of 75 surgeons with 1 to 30 years' experience (mean, 7 years) were filmed from January 1, 2017, to December 31, 2020, managing catastrophic surgical hemorrhage in a high-fidelity cadaveric training exercise at nationwide training courses. Videos were annotated from January 1 to June 30, 2021. Interventions: Surgeons received expert coaching between 2 trials. Main Outcomes and Measures: Hemostasis within 5 minutes (task success, dichotomous), time to hemostasis (in seconds), and blood loss (in milliliters) were recorded. Deep neural networks (DNNs) were trained to detect surgical instruments in view. Model performance was measured using mean average precision (mAP), sensitivity, and positive predictive value. Results: SOCAL contains 31 443 frames with 65 071 surgical instrument annotations from 147 trials with associated surgeon demographic characteristics, time to hemostasis, and recorded blood loss for each trial. Computer vision-based instrument detection methods using DNNs trained on SOCAL achieved a mAP of 0.67 overall and 0.91 for the most common surgical instrument (suction). Hemorrhage control challenges standard object detectors: detection of some surgical instruments remained poor (mAP, 0.25). On real intraoperative video, the model achieved a sensitivity of 0.77 and a positive predictive value of 0.96. Instrument use metrics derived from the SOCAL video were significantly associated with performance (blood loss). Conclusions and Relevance: Hemorrhage control is a high-stakes adverse event that poses unique challenges for video analysis, but no data sets of hemorrhage control exist. The use of SOCAL, the first data set to depict hemorrhage control, allows the benchmarking of data science applications, including object detection, performance metric development, and identification of metrics associated with outcomes. In the future, SOCAL may be used to build and validate surgical data science models.

Robotic and robot-assisted skull base neurosurgery: systematic review of current applications and future directions.

OBJECTIVE: The utility of robotic instrumentation is expanding in neurosurgery. Despite this, successful examples of robotic implementation for endoscopic endonasal or skull base neurosurgery remain limited. Therefore, the authors performed a systematic review of the literature to identify all articles that used robotic systems to access the sella or anterior, middle, or posterior cranial fossae. METHODS: A systematic review of MEDLINE and PubMed in accordance with PRISMA guidelines performed for articles published between January 1, 1990, and August 1, 2021, was conducted to identify all robotic systems (autonomous, semiautonomous, or surgeon-controlled) used for skull base neurosurgical procedures. Cadaveric and human clinical studies were included. Studies with exclusively otorhinolaryngological applications or using robotic microscopes were excluded. RESULTS: A total of 561 studies were identified from the initial search, of which 22 were included following full-text review. Transoral robotic surgery (TORS) using the da Vinci Surgical System was the most widely reported system (4 studies) utilized for skull base and pituitary fossa procedures; additionally, it has been reported for resection of sellar masses in 4 patients. Seven cadaveric studies used the da Vinci Surgical System to access the skull base using alternative, non-TORS approaches (e.g., transnasal, transmaxillary, and supraorbital). Five cadaveric studies investigated alternative systems to access the skull base. Six studies investigated the use of robotic endoscope holders. Advantages to robotic applications in skull base neurosurgery included improved lighting and 3D visualization, replication of more traditional gesture-based movements, and the ability for dexterous movements ordinarily constrained by small operative corridors. Limitations included the size and angulation capacity of the robot, lack of drilling components preventing fully robotic procedures, and cost. Robotic endoscope holders may have been particularly advantageous when the use of a surgical assistant or second surgeon was limited. CONCLUSIONS: Robotic skull base neurosurgery has been growing in popularity and feasibility, but significant limitations remain. While robotic systems seem to have allowed for greater maneuverability and 3D visualization, their size and lack of neurosurgery-specific tools have continued to prevent widespread adoption into current practice. The next generation of robotic technologies should prioritize overcoming these limitations.

Use of Salvage Surgery or Stereotactic Radiosurgery for Multiply Recurrent Skull Base Chordomas: A Single-Institution Experience and Review of the Literature.

Introduction Chordomas are locally destructive neoplasms characterized by appreciable recurrence rates after initial multimodality treatment. We examined the outcome of salvage treatment in recurrent/progressive skull base chordomas. Methods This is a retrospective review of recurrent/progressive skull base chordomas at a tertiary urban academic medical center. The outcomes evaluated were overall survival, progression-free survival (PFS), and incidence of new toxicity. Results Eighteen consecutive patients who underwent ≥1 course of treatment (35.3% salvage surgery, 23.5% salvage radiation, and 41.2% both) were included. The median follow-up was 98.6 months (range 16-215 months). After initial treatment, the median PFS was 17.7 months (95% confidence interval [CI]: 4.9-22.6 months). Following initial therapy, age ≥ 40 had improved PFS on univariate analysis ( p = 0.03). All patients had local recurrence, with 15 undergoing salvage surgical resections and 16 undergoing salvage radiation treatments (mostly stereotactic radiosurgery [SRS]). The median PFS was 59.2 months (95% CI: 4.0-99.3 months) after salvage surgery, 58.4 months (95% CI: 25.9-195 months) after salvage radiation, and 58.4 months (95% CI: 25.9.0-98.4 months) combined. Overall survival for the total cohort was 98.7% ± 1.7% at 2 years and 92.8% ± 5.5% at 5 years. Salvage treatments were well-tolerated with two patients (11%) reporting tinnitus and one patient each (6%) reporting headaches, visual field deficits, hearing loss, anosmia, dysphagia, or memory loss. Conclusion Refractory skull base chordomas present a challenging treatment dilemma. Repeat surgical resection or SRS seems to provide adequate salvage therapy that is well-tolerated when treated at a tertiary center offering multimodality care.

Thermal Conductance Through the Skull Base From Endoscopic Surgery Cauterization Instruments: Cadaver and Goat Model.

OBJECTIVE: Cauterization prevents hemorrhage and optimizes the surgical field during endoscopic sinus surgery but may cause injury to nearby structures. The objective of this study is to examine thermal conductance from cauterization equipment across the skull base. STUDY DESIGN: Cadaver and animal model. SETTING: Surgical skills laboratory of an academic tertiary medical institution. METHODS: A pilot study was conducted with a deidentified cadaver head and expanded to a goat head animal model. Endoscopic dissection was performed to expose the lamina papyracea, ethmoid roof, sphenoid roof, and frontal sinus. Cautery was applied to the frontal sinus of goat heads, and temperatures were measured via thermocouple sensors placed along the intracranial skull base. Surgical instruments studied included monopolar, bipolar, and endoscopic bipolar devices at various power settings. RESULTS: Temperature increase, as averaged across all cautery powers and measurement positions, was highest for the monopolar cautery (17.55 °C) when compared with the bipolar and endoscopic bipolar devices (<2 °C for bipolar, Endo-Pen, Stammberger, and Wormald; P < .001). Monopolar cautery reached 30.86 °C at high power when averaged over all positions (P < .001) as compared with <3 °C for the other instruments. Temperatures rose as power of cautery was increased from low to medium and high. Temperatures decreased as the distance of the thermocouple sensor probe from the cautery origin increased. CONCLUSION: Thermal conductance across the skull base varies depending on equipment and power of cautery, with monopolar resulting in the largest temperature increase. Choice and implementation of cauterization instruments have implications on inadvertent transmission of thermal energy during endoscopic sinus surgery.

Improved surgeon performance following cadaveric simulation of internal carotid artery injury during endoscopic endonasal surgery: training outcomes of a nationwide prospective educational intervention.

OBJECTIVE: Internal carotid artery injury (ICAI) is a rare, life-threatening complication of endoscopic endonasal approaches that will be encountered by most skull base neurosurgeons and otolaryngologists. Rates of surgical proficiency for managing ICAI are not known, and the role of simulation to improve performance has not been studied on a nationwide scale. METHODS: Attending and resident neurosurgery and otorhinolaryngology surgeons (n = 177) were recruited from multicenter regional and national training courses to assess training outcomes and validity at scale of a prospective educational intervention to improve surgeon technical skills using a previously validated, perfused human cadaveric simulator. Participants attempted an initial trial (T1) of simulated ICAI control using their preferred technique. An educational intervention including personalized instruction was performed. Participants attempted a second trial (T2). Task success (dichotomous), time to hemostasis (TTH), estimated blood loss (EBL), and surgeon heart rate were measured. RESULTS: Participant rating scales confirmed that the simulation retained face and construct validity across eight instructional settings. Trial success (ICAI control) improved from 56% in T1 to 90% in T2 (p < 0.0001). EBL and TTH decreased by 37% and 38%, respectively (p < 0.0001). Postintervention resident surgeon performance (TTH, EBL, and success rate) was superior to preintervention attending surgeon performance. The most improved quartile of participants achieved 62% improvement in TTH and 73% improvement in EBL, with trial success improvement from 25.6% in T1 to 100% in T2 (p < 0.0001). Baseline surgeon confidence was uncorrelated with T1 success, while posttraining confidence correlated with T2 success. Tachycardia was measured in 57% of surgeon participants, but was attenuated during T2, consistent with development of resiliency. CONCLUSIONS: Prior to training, many attending and most resident surgeons could not manage the rare, life-threatening intraoperative complication of ICAI. A simulated educational intervention significantly improved surgeon performance and remained valid when deployed at scale. Simulation also promoted the development of favorable cognitive skills (accurate perception of skill and resiliency). Rare, life-threatening intraoperative complications may be optimal targets for educational interventions using surgical simulation.