Case Curve: A Novel Web-Based Platform and Mobile Phone Application to Evaluate Surgical Competence in Graduate Medical Education.

BACKGROUND AND OBJECTIVES: Competency-based medical education is well established, yet methods to evaluate and document acquisition of surgical skill remain underdeveloped. We describe a novel web-based application for competency-based surgical education at a single neurosurgical department over a 3-year period. METHODS: We used a web-based application to track procedural and cognitive skills acquisition for neurosurgical residents. This process included self-assessment, resident peer evaluations, evaluations from supervising attending physicians, and blinded video reviews. Direct observation by faculty and video recordings were used to evaluate surgical skill. Cases were subdivided into component skills, which were evaluated using a 5-point scale. The learning curve for each skill was continuously updated and compared with expectations. Progress was reviewed at a monthly surgical skills conference that involved discussion and analysis of recorded surgical performances. RESULTS: During an escalating 3-year pilot from 2019 to 2022, a total of 1078 cases in 39 categories were accrued by 17 resident physicians with 10 neurosurgical faculty who participated as evaluators. A total of 16 251 skill performances in 110 categories were evaluated. The most evaluated skills were those that were common to several types of procedures, such as positioning, hemostasis, and wound closure. The concordance between attending evaluations and resident self-evaluations was 76%, with residents underestimating their performance in 17% of evaluations and overestimating in 7%. CONCLUSION: We developed a method for evaluating and tracking surgical resident skill performance with an application that provides timely and actionable feedback. The data collected from this system could allow more accurate assessments of surgical skills and deeper insights into factors influencing surgical skill acquisition.

The Development of Skull Base Surgery as a Discipline: Remembrances of Dr Jon H. Robertson.

Skull base surgery is a young surgical subspecialty currently led by its second generation of surgeons. At present, there is no literature that narrates the connection of the present to the past. An extended interview was held with Dr Jon H. Robertson, who helped establish the subspecialty in Memphis, TN, to aid in identifying and connecting sentinel events and key figures in the development of the discipline. The field drastically evolved during his era of practice (1975-present), with the advent of advanced imaging and technology, as well as the emergence of multidisciplinary skull base surgical teams. The intersection of the careers of Jon H. Robertson, James T. Robertson, Gale Gardner, Edwin Cocke, John Shea, Jr., and Jerrall Crook in Memphis catalyzed the standardization of a multidisciplinary approach to cranial base pathology. We report the findings of Dr Jon H. Robertson's extended interview, told against the backdrop of the history of the subspecialty. The story of the development of skull base surgery is told from the unique perspective of one who lived and shaped a pivotal segment in this historical timeline.

Skull Base Registries: A Roadmap.

Hospitals, payors, and patients increasingly expect us to report our outcomes in more detail and to justify our treatment decisions and costs. Although there are many stakeholders in surgical outcomes, physicians must take the lead role in defining how outcomes are assessed. Skull base lesions interact with surrounding anatomy to produce a complex spectrum of presentations and surgical challenges, requiring a wide variety of surgical approaches. Moreover, many skull base lesions are relatively rare. These factors and others often preclude the use of prospective randomized clinical trials, thus necessitating alternate methods of scientific inquiry. In this paper, we propose a roadmap for implementing a skull base registry, along with expected benefits and challenges.

Determinants of tumor treating field usage in patients with primary glioblastoma: A single institutional experience.

Background: Determinates of tumor treating fields (TTFields) usage in patients receiving combined modality therapy for primary IDH wild-type glioblastoma are currently unknown. Methods: Ninety-one patients underwent maximal debulking surgical resection, completed external beam radiotherapy with concurrent Temozolomide (TMZ), and initiated adjuvant TMZ with or without TTFields. We performed a retrospective analysis of patient, tumor, and treatment-related factors that affected TTFields usage. Results: We identified three TTFields usage subgroups: 32 patients that declined TTFields, 40 patients that started, but had monthly compliance of less than 75% or used it for less than 2 months, and 19 patients who used TTFields for 2 or more months and maintained average monthly compliance greater than 75%. With 26.5 months median follow-up for surviving patients, the 1- and 3-year actuarial overall survival for all patients was 80% and 18%, respectively. On multivariate analysis TTFields use (P = .03), extent of surgical resection (P = 0.02), and MGMT methylation status (P = .01) were significantly associated with overall survival. TTFields usage was explored as a continuous variable and higher average usage was associated with longer overall survival (P = .03). There was no relationship between patient, tumor, or treatment-related factors and a patient's decision to use TTFields. Conclusions: No subgroup of patients was more or less likely to initiate TTFields therapy and no subgroup was more or less likely to use TTFields as prescribed. The degree of TTFields compliance may be associated with improved survival independent of other factors.

The Asterion-to-Transverse Process of the Atlas Line as a Surgical Landmark.

Introduction Proposed landmarks to predict the anatomical location and trajectory of the sigmoid sinus have varying degrees of reliability. Even with neuronavigation technology, landmarks are crucial in planning and performing complex approaches to the posterolateral skull base. By combining two major dependable structures-the asterion (A) and transverse process of the atlas (TPC1)-we investigate the A-TPC1 line in relation to the sigmoid sinus and in partitioning surgical approaches to the region. Methods We dissected six cadaveric heads (12 sides) to expose the posterolateral skull base, including the mastoid and suboccipital bone, TPC1 and suboccipital triangle, distal jugular vein and internal carotid artery, and lower cranial nerves in the distal cervical region. We inspected the A-TPC1 line before and after drilling the mastoid and occipital bones and studied the relationship of the sigmoid sinus trajectory and major muscular elements related to the line. We retrospectively reviewed 31 head and neck computed tomography (CT) angiograms (62 total sides), excluding posterior fossa or cervical pathologies. Bone and vessels were reconstructed using three-dimensional segmentation software. We measured the distance between the A-TPC1 line and sigmoid sinus at different levels: posterior digastric point (DP), and maximal distances above and below the digastric notch. Results A-TPC1 length averaged 65 mm and was posterior to the sigmoid sinus in all cadaver specimens, coming closest at the level of the DP. Using the transverse-asterion line as a rostrocaudal division and skull base as a horizontal plane, we divided the major surgical approaches into four quadrants: distal cervical/extreme lateral and jugular foramen (anteroinferior), presigmoid/petrosal (anterosuperior), retrosigmoid/suboccipital (posterosuperior), and far lateral/foramen magnum regions (posteroinferior). Radiographically, the A-TPC1 line was also posterior to the sigmoid sinus in all sides and came closest to the sinus at the level of DP (mean, 7 mm posterior; range, 0-18.7 mm). The maximal distance above the DP had a mean of 10.1 mm (range, 3.6-19.5 mm) and below the DP 5.2 mm (range, 0-20.7 mm). Conclusion The A-TPC1 line is a helpful landmark reliably found posterior to the sigmoid sinus in cadaveric specimens and radiographic CT scans. It can corroborate the accuracy of neuronavigation, assist in minimizing the risk of sigmoid sinus injury, and is a useful tool in planning surgical approaches to the posterolateral skull base, both preoperatively and intraoperatively.

Erratum: Skull Base Registries: A Roadmap.

[This corrects the article DOI: 10.1055/a-1934-9191.].

Simplifying the Surgical Classification and Approach to the Posterolateral Skull Base and Jugular Foramen Using Anatomical Triangles.

Introduction Lesions of the jugular foramen (JF) and postero-lateral skull base are difficult to expose and exhibit complex neurovascular relationships. Given their rarity and the increasing use of radiosurgery, neurosurgeons are becoming less experienced with their surgical management. Anatomical factors are crucial in designing the approach to achieve a maximal safe resection. Methods and methods Six cadaveric heads (12 sides) were dissected via combined post-auricular infralabyrinthine and distal transcervical approach with additional anterior transstyloid and posterior far lateral exposures. Contiguous surgical triangles were measured, and contents were analyzed. Thirty-one patients (32 lesions) were treated surgically between 2000 and 2016 through different variations of the retro-auricular distal cervical transtemporal approaches. Results We anatomically reviewed the carotid, stylodigastric, jugular, condylar, suboccipital, deep condylar, mastoid, suprajugular, suprahypoglossal (infrajugular), and infrahypoglossal triangles. Tumors included glomus jugulare, lower cranial nerve schwannomas or neurofibromas, meningiomas, chondrosarcoma, adenocystic carcinoma, plasmacytoma of the occipitocervical joint, and a sarcoid lesion. We classified tumors into extracranial, intradural, intraosseous, and dumbbell-shaped, and analyzed the approach selection for each. Conclusion Jugular foramen and posterolateral skull base lesions can be safely resected through a retro-auricular distal cervical lateral skull base approach, which is customizable to anatomical location and tumor extension by tailoring the involved osteo-muscular triangles.

Deconstruction of the Surgical Approach to the Jugular Foramen Region: Anatomical Study.

Introduction The jugular foramen occupies a complex and deep location between the skull base and the distal-lateral-cervical region. We propose a morphometric anatomical model to deconstruct its surgical anatomy and offer various quantifiable target-guided exposures and angles-of-attack. Methods Six cadaveric heads (12 sides) were dissected using a combined postauricular infralabyrinthine and distal transcervical approach with additional anterior transstyloid and posterior far lateral exposures. We identified anatomical landmarks and combined new and previously described contiguous triangles to expose the region; we defined the jugular and deep condylar triangles. Angles-of-attack to the jugular foramen were measured after removing the digastric muscle, styloid process, rectus capitis lateralis, and occipital condyle. Results Removing the digastric muscle and styloid process allowed 86.4° laterally and 85.5° anteriorly, respectively. Resecting the rectus capitis lateralis and jugular process provided the largest angle-of-attack (108.4° posteriorly). The occipital condyle can be drilled in the deep condylar triangle only adding 30.4° medially. A purely lateral approach provided a total of 280.3°. Cutting the jugular ring and mobilizing the vein can further expand the medial exposure. Conclusion The microsurgical anatomy of the jugular foramen can be deconstructed using a morphometric model, permitting a surgical approach customized to the pathology of interest.

Predictors of extended length of stay, discharge to inpatient rehab, and hospital readmission following elective lumbar spine surgery: introduction of the Carolina-Semmes Grading Scale.

OBJECTIVE Extended hospital length of stay (LOS), unplanned hospital readmission, and need for inpatient rehabilitation after elective spine surgery contribute significantly to the variation in surgical health care costs. As novel payment models shift the risk of cost overruns from payers to providers, understanding patient-level risk of LOS, readmission, and inpatient rehabilitation is critical. The authors set out to develop a grading scale that effectively stratifies risk of these costly events after elective surgery for degenerative lumbar pathologies. METHODS The Quality and Outcomes Database (QOD) registry prospectively enrolls patients undergoing surgery for degenerative lumbar spine disease. This registry was queried for patients who had undergone elective 1- to 3-level lumbar surgery for degenerative spine pathology. The association between preoperative patient variables and extended postoperative hospital LOS (LOS ≥ 7 days), discharge status (inpatient facility vs home), and 90-day hospital readmission was assessed using stepwise multivariate logistic regression. The Carolina-Semmes grading scale was constructed using the independent predictors for LOS (0-12 points), discharge to inpatient facility (0-18 points), and 90-day readmission (0-6 points), and its performance was assessed using the QOD data set. The performance of the grading scale was then confirmed separately after using it in 2 separate neurosurgery practice sites (Carolina Neurosurgery & Spine Associates [CNSA] and Semmes Murphey Clinic). RESULTS A total of 6921 patients were analyzed. Overall, 290 (4.2%) patients required extended LOS, 654 (9.4%) required inpatient facility care/rehabilitation on hospital discharge, and 474 (6.8%) were readmitted to the hospital within 90 days postdischarge. Variables that remained as independently associated with these unplanned events in multivariate analysis included age ≥ 70 years, American Society of Anesthesiologists Physical Classification System class > III, Oswestry Disability Index score ≥ 70, diabetes, Medicare/Medicaid, nonindependent ambulation, and fusion. Increasing point totals in the Carolina-Semmes scale effectively stratified the incidence of extended LOS, discharge to facility, and readmission in a stepwise fashion in both the aggregate QOD data set and when subsequently applied to the CNSA/Semmes Murphey practice groups. CONCLUSIONS The authors introduce the Carolina-Semmes grading scale that effectively stratifies the risk of prolonged hospital stay, need for postdischarge inpatient facility care, and 90-day hospital readmission for patients undergoing first-time elective 1- to 3-level degenerative lumbar spine surgery. This grading scale may be helpful in identifying patients who may require additional resource utilization within a global period after surgery.

A far-lateral approach for removal of a C1-2 extradural neurofibroma.

A young man with type 1 neurofibromatosis presented with progressive myelopathy. Imaging revealed an anterolateral mass within the spinal canal at C1-2, with severe compression of the spinal cord. A far-lateral approach was used to remove the mass, which proved to be an extradural neurofibroma. This narrated stereoscopic video details the important steps of the operation. The video can be found here: http://youtu.be/td4MjLtiMbk .

Resection of an anterior spinal cord AVM through a far-lateral approach.

A small arteriovenous malformation near the craniocervical junction with contributions from the anterior spinal artery was discovered in a young developmentally-delayed woman after she presented with altered mental status and evidence of subarachnoid hemorrhage. The malformation could not be completely treated with endovascular therapy, so it was resected through a far-lateral approach. This stereoscopic video demonstrates how to gain the exposure needed to address a lesion in this area. The video can be found here: http://youtu.be/ByjPGm_eXLc .

Repeat Gamma Knife surgery for trigeminal neuralgia: long-term results.

OBJECT: The purpose of this study was to assess the long-term outcome achieved after repeat Gamma Knife surgery (GKS) for trigeminal neuralgia (TN) using a uniform treatment plan. METHODS: Between 1985 and 2010, 53 patients underwent repeat GKS for refractory TN. In the initial GKS, which involved targeting the root entry zone of the trigeminal nerve, a maximal dose of 80 Gy was used with a 4-mm collimator so that the 50% isodose line abutted the pons. In the second GKS, the treatment plan consisted of a 70-Gy dose directed at a target 4-5 mm distal to the first target on the trigeminal nerve. The mean follow-up duration in these patients was 42 months. Outcomes were defined using the Marseille scale: excellent (Class I or II, no pain with or without medications), good (Class III or IV, ≥ 50% relief), and poor (Class V, < 50% relief). RESULTS: Trigeminal neuralgia pain was controlled (≥ 50% improvement with or without medications) after repeat GKS in 70% of patients at 1 year, 50% at 3 years, 50% at 5 years, and 50% at 10 years, as defined by a Kaplan-Meier analysis. A correlation was found between facial numbness and pain relief (p = 0.047). No difference was found between patients with Type 1 TN and those with Type 2 TN, and there was no correlation between the best relief obtained and long-term durability of relief from pain. Twenty-two patients (47.8%) described their trigeminal dysfunction in the following manner: numbness (45.6%), dry eye (10.9%), taste change (8.7%), or jaw weakness (2.2%). In only 8.7% of cases did the patient experience facial numbness that was regarded as bothersome. CONCLUSIONS: Repeat GKS for TN at the doses used provides substantial long-term relief. Treatment failure occurred up to 28 months after the second GKS. Facial numbness correlated with more durable pain relief after repeat GKS in this series.

The treatment of advanced sinonasal malignancies with pre-operative intra-arterial cisplatin and concurrent radiation.

INTRODUCTION: Malignancies of the nasal and paranasal sinuses are uncommon tumors, accounting for only 3% of all aerodigestive tract neoplasms. Despite advances in surgical techniques and continued evolution of adjuvant therapies, the 5-year mortality remains unusually high at greater than 50%. In 1996, we begin utilizing a novel strategy in the treatment of advanced sinonasal carcinomas. This consisted of neoadjuvant selective intra-arterial cisplatin with concurrent radiation therapy (acronym RADPLAT) followed by a conservative craniofacial resection. We now report our results for 11 patients treated with this regimen. METHODS: Between July 1996 and April 2003, 11 patients with advanced sinonasal malignancies underwent treatment utilizing the RADPLAT protocol followed by a planned surgical resection via a craniofacial approach. Patient charts, operative notes, follow-up clinic notes, and pre- and post-operative imaging studies were reviewed in detail for each subject. RESULTS: Histopathological analysis of the tumors revealed seven squamous cell carcinomas (64%), two adenocarcinomas (18%), one adenoid cystic carcinoma (9%), and one sinonasal undifferentiated carcinoma (9%). T4N0M0 disease was present in nine patients (81%), and two patients had T3N0M0 disease (19%). Survival was calculated using the Kaplan-Meier method with an overall survival of 81% at 5 years and a progression-free survival at 5 years of 67%. Mean follow-up is 57.2 months ranging from 12 to 95 months. CONCLUSIONS: The treatment of advanced sinonasal malignancies with pre-operative intra-arterial cisplatin and concurrent radiation results in a significant improvement in survival. This can be done safely with high response rates and excellent loco-regional control in T3 and T4 disease. Although are results are encouraging, there is a need for a cooperative, multi-institutional, prospective study.