Citations

Introduction Optimal management of vestibular schwannoma (VS) demands involvement of an experienced multidisciplinary team. As the number of training programs in neurotology and skull base neurosurgery continues to rise, ensuring that trainees are capable of evidence-based decision-making and treatment, whether microsurgical or radiosurgical, is of paramount importance. The purpose of this study is to characterize the landscape of neurotologic and neurosurgical fellowship training programs in North America, with special reference to VS management. Methods A 64-item web-based survey assessing VS practice trends was devised by members of the North American Skull Base Society (NASBS) Research Task Force and distributed electronically to NASBS membership via SurveyMonkey as a cross-sectional study. Participation was entirely voluntary and there was no remuneration for survey completion. The survey link was active from November 29 to December 14, 2016. Results Of 719 members of the NASBS who were emailed a survey link, a total of 57 were returned (8%) completed surveys. Of all respondents, 51 (89%) claimed to have formal training in skull base neurosurgery or neurotology. Thirty-three respondents (65%) were skull base neurosurgeons while the remainder were neurotologists (n = 18; 35%). Institutions with fellowship programs tended to have a higher surgical, radiosurgical, and overall case volume than those with a residency program alone. However, 20% of respondents at institutions with fellowship programs reported evaluating less than 50 new diagnoses of VS per year and 12% reported a surgical case volume of less than 10 cases per year. Conclusion As the number of skull base training programs expands, it is our duty to ensure that trainees gain sufficient experience to enter independent practice with the ability to exercise informed decision-making and safely perform VS surgery and radiosurgery. In the current training climate, implementing multidisciplinary care models, formalized training requirements, and emerging surgical simulators will support the development of minimum proficiencies in VS care.

Background There is little data regarding postoperative outcomes of patients with obstructive sleep apnea (OSA) undergoing skull base surgery. The purpose of this study is to determine an association between risk factors and proximity of cerebrospinal fluid (CSF) leak to surgery in patients with OSA undergoing endoscopic skull base surgery. Methods A retrospective review of neurosurgical inpatients, with and without OSA, at a tertiary care institution from 2002 to 2015 that experienced a postoperative CSF leak after undergoing endoscopic skull base surgery. Results Forty patients met inclusion criteria, 12 (30%) with OSA. OSA patients had significantly higher body mass index (BMI; median 39.4 vs. 31.7, p < 0.01) and were more likely to have diabetes (41.7 vs. 10.7%, p = 0.04) than non-OSA patients; otherwise there were no significant differences in clinical comorbidities. No patients restarted positive pressure ventilation (PPV) in the inpatient setting. The type of repair was not a significant predictor of the time from surgery to leak. Patients with OSA experienced postoperative CSF leak 49% sooner than non-OSA patients (Hazard Ratio 1.49, median 2 vs. 6 days, log-rank p = 0.20). Conclusion Patients with OSA trended toward leaking earlier than those without OSA, and no OSA patients repaired with a nasoseptal flap (NSF) had a leak after postoperative day 5. Due to a small sample size this trend did not reach significance. Future studies will help to determine the appropriate timing for restarting PPV in this high risk population. This is important given PPV's significant benefit to the patient's overall health and its ability to lower intracranial pressure.

Abstract Objective The Superior Mesenteric Artery Syndrome (SMAS) was first described by Rokitansky in 1842. Clinical symptoms include postprandial pain, nausea, vomiting and weight loss. Duodenojejunostomy is the treatment of choice for patients with SMAS. We now present a case of a young female with SMAS who successfully underwent laparoscopic duodenojejunostomy. Indications The first line treatment for SMAS is medical management, which includes infusion therapy, bowel rest, parenteral nutrition and a nasojejunal feeding tube inserted into the jejunum past the obstruction. If medical therapy fails, surgery is recommended. Procedure A symptomatic patient with body mass index (BMI) of 19.4 kg/m2 underwent laparoscopic duodenojejunostomy. The patient tolerated the procedure well. The post-operative period was uneventful and the patient was discharged after three days. On six month follow up, the patient had gained weight and her symptoms were completely resolved. Conclusion SMAS is still a poorly recognised pathology. A high index of suspicion should be given for patients with unclear causes of postprandial nausea, vomiting and abdominal pain, especially in young females. A laparoscopic approach seems to be safe and effective for patients with SMAS.

Background Long surgical procedures with loupe magnification and microscopes may put microsurgeons at an increased risk of musculoskeletal discomfort. Identifying the prevalence and impact of work-related musculoskeletal discomfort may guide preventive strategies to prolong well-being, job satisfaction, and career duration. Methods An online 29-question survey was designed to evaluate work-related musculoskeletal discomfort. The survey was created and distributed electronically through a private survey research center and was sent to the members of the American Society for Reconstructive Microsurgery. Results There were 117 respondents (16.7% response rate): 80% were men; 69% were aged 31 to 50 years; and 68% were in academic practice. On a scale of 0 to 10 (0, no pain and 10, worst pain), the median for work-related musculoskeletal discomfort for surgery without loupes or microscope was 2; with loupes, 4; and with a microscope, 5. Pain was most common in the neck. Half of the surgeons reported pain within 4 hours of surgery, and 57% feared that pain would influence future surgical performance. Surgeon discomfort affected posture (72%), stamina (36%), sleep (29%), relationships (25%), concentration (22%), and surgical speed (19%). Tremor caused by the discomfort occurred in 8%. Medical treatment for discomfort was sought by 29%. Time off work for treatment occurred for 8%. Conclusion Work-related musculoskeletal discomfort can affect many aspects of a microsurgeon's life and has the potential to limit a surgeon's ability to operate. Therefore, more emphasis is needed in the surgical community on the important issues of occupational health and surgical ergonomics for microsurgeons.

Objectives Although vestibular schwannomas (VS) are known to cause cranial nerve deficits, cerebellar symptoms, and hydrocephalus, the role of these symptoms as the key driver of presentation from the patient's perspective has not been described. Our objective was to survey a large, retrospective VS cohort to document the patient-reported principal initial symptom, and self-reported tumor size, and to study trends in VS patient presentation. Methods Patients diagnosed with VS at our tertiary referral center and belonging to the Acoustic Neuroma Association (ANA) answered a questionnaire between 2015 and 2017. Demographic data, self-reported tumor size, and symptomatology were analyzed. Results 1,304 patients completed the questionnaire. Tumors were diagnosed from 1966 to 2017 at a mean 51.8 years (range: 8–86 years); 66% were female, and 1.1% had confirmed neurofibromatosis type 2 (NF2). Tumor size was reported using a 6-point scale: 0 to 1 cm (22.9%), 1 to 2 cm (28.7%), 2 to 3 cm (20.5%), 3 to 4 cm (10%), greater than 4 cm (7.2%), and unknown (10.6%). Hearing loss was the most common symptom that led to diagnosis (51.5%), followed by dizziness (17%), tinnitus (11.2%), and incidental diagnosis (10.2%); a fraction that has increased significantly in the last decade (p = 0.022). Larger tumors and NF2 were significantly associated with young age (p < 0.001). Conclusion Our large-scale questionnaire-driven review of 1,304 patients confirms that VS presentations are stereotypical, with most individuals recalling hearing loss, dizziness, or tinnitus as their chief complaint. Many tumors were incidentally diagnosed; an expanding population, attributable to increased access to magnetic resonance imaging (MRI). Large tumors were significantly more prevalent among younger patients at diagnosis, excluding NF2 patients, suggesting a more aggressive tumor biology that remains incompletely understood.

Introduction Although numerous anatomical and operative atlases have been published, those that have focused on the skull base either have provided views that are quite difficult to achieve in the operating room to better depict surgical anatomy or are written at the level of an audience with considerable knowledge and experience. Methods Five sides of three formalin-fixed latex-injected specimens were dissected under microscopic magnification. A posterior petrosectomy approach was performed by three neurosurgical residents at different training levels with limited previous experience in anatomical dissection mentored by the senior authors (C. L. W. D. and M. J. L.) and a clinical skull base fellow with additional anatomical dissection experience (M. P. C.). Anatomical dissections were performed until the expected level of dissection quality was achieved to demonstrate each important step of the surgical approach that would be understandable to all trainees of all levels. Following dissection education, representative case applications were reviewed. Results The posterior petrosectomy (also known as presigmoid retrolabyrinthine approach) affords excellent access to cranial nerves III to XI and a diverse array of pathologies. Key steps include positioning and skin incision, scalp and muscle flaps, burr holes, craniotomy flap elevation, superficial mastoidectomy, otic capsule exposure and presigmoid dura decompression, primary presigmoid durotomy, inferior temporal durotomy, superior petrosal sinus ligation, tentorium sectioning, and final exposure. Conclusion The posterior petrosectomy is a challenging approach; thorough operative-style laboratory dissection is essential to provide trainees with a suitable guide. We describe a comprehensive approach to learning this technique, intended to be understandable and usable by a resident audience.

Abstract Background and study aims The US FDA recently approved a cancer treatment with pembrolizumab based upon the tumor biomarker status of deficient mismatch repair (dMMR) rather than a specific disease-based approach. We sought to determine if endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB) could determine dMMR and quantification of PD-L1 expression to potentially guide the delivery of tumor agnostic immunotherapy. Patients and methods Immunohistochemistry was performed on archived pancreas core biopsy specimens. Tumors with absent nuclear staining of DNA mismatch repair proteins represented dMMR. Tumors were considered to have any or high PD-L1 expression, if expressed in ≥ 1 % or ≥ 50 % of tumor cells. Results Histologic specimen adequacy for MMR status assessment was satisfactory in 97.2 % of tumors. dMMR and high PD-L1 expression was identified in 3 % and 8.1 % of the cohort. Conclusion In the setting of tumor type agnostic immunotherapy, it is projected that at least 3 % of malignant pancreas lesions will be sensitive to pembrolizumab and up to 8 % sensitive to the family of immune checkpoint inhibitors. This highlights the expanding role of EUS-FNB in the field of precision immuno-oncology.

AbstractThe course and pathogenesis of Graves’ disease and Graves’ ophthalmopathy are interdependent, influencing each other’s therapeutic choices. Multiple factors including geographic location, access to medical services, patient and physician preferences influence the management of these conditions. Graves’ disease is classically managed with one of three treatment options – antithyroid drugs, radioactive iodine, and thyroidectomy. In recent years, there has been a shift towards antithyroid drugs, including long term therapy with these agents, given the advantage of avoiding hypothyroidism and the apparent safety of this approach. In addition, new therapies are (slowly) emerging, focusing on immunomodulation. Technological advances are opening doors to non-pharmaceutical interventions that aim to deal with both structural thyroid abnormalities as well as biochemical abnormalities of hyperthyroidism. Graves’ ophthalmopathy management is guided by its activity and severity status, with treatment options including smoking cessation, control of hyperthyroidism, local eye measures, glucocorticoids, selenium, orbital radiotherapy, and surgery. In addition to these established treatment choices, new immunotherapy-based approaches are being tested. Some of them (tocilizumab and teprotumumab) are very promising but further evaluation is needed before we can establish their role in clinical care. Agents identified as beneficial in Graves’ disease management will likely be tested in Graves’ ophthalmopathy as well. In the coming years, our main clinical responsibility will be to find the proper balance between the benefits and potential risks of these incoming therapies, and to identify the subgroups of patients where this ratio is most likely to favor a safe and successful therapeutic outcome.