Morris, Jonathan M.

BACKGROUND: Selection of skull base approaches is a critical skill for complex cranial surgery, which demands nuanced understanding of neuroanatomy and pathology. OBJECTIVE: To develop novel pedagogical resources for approach selection education and assessment. METHODS: A prospectively maintained skull base registry was screened for posterior fossa tumors amenable to 3-dimensional (3D) modeling of multiple operative approaches. Inclusion criteria were high-resolution preoperative and postoperative computed tomography and MRI studies (≤1 mm) and consensus that at least 3 posterior fossa craniotomies would provide feasible access. Cases were segmented using Mimics and modeled using 3-Matic. Clinical Vignettes, Approach Selection Questionnaire, and Clinical Application Questionnaire were compiled for implementation as a teaching/testing tool. RESULTS: Seven cases were selected, each representing a major posterior fossa approach group. 3D models were rendered using clinical imaging for the primary operative approach, as well as a combination of laboratory neuroanatomic data and extrapolation from comparable craniotomies to generate 2 alternative approaches in each patient. Modeling data for 3D figures were uploaded to an open-sourced database in a platform-neutral fashion (.x3d) for virtual/augmented reality and 3D printing applications. A semitransparent model of each approach without pathology and with key deep structures visualized was also modeled and included for comprehensive understanding. CONCLUSION: We report a novel series of open-source 3D models for skull base approach selection training, with supplemental resources. To the best of our knowledge, this is the first such series designed for pedagogical purposes in skull base surgery or centered on open-source principles.

Objectives The aim of this study is to introduce the infrapedicular approach to CT-guided spine interventions, a specialized technique that can safely expand the scope of spine lesions amenable to treatment, and to document the feasibility in a variety of procedural scenarios to the extent possible with a retrospective case series. Methods Data from 24 cases performed at a single institution over a 10-year period were retrospectively reviewed to assess the technical feasibility and safety profile of the technique. Results The infrapedicular approach enabled a technically satisfactory procedural result in 24 cases (mean age 63.9 years, range 35–83 years). Two peri-procedural complications occurred, including a small pneumothorax and a cerebrospinal fluid leak, both of which resolved with conservative treatment. No lasting injurious effects or additional complications were identified. The infrapedicular approach was found to be particularly useful in multiple technically challenging scenarios: it facilitates access to lesions in the inferior vertebral body, allows biopsy, cement augmentation, or ablation of high thoracic lesions difficult to treat due to limitations of steep angulation of fluoroscopy and CT scanners, and enables treatment of large lesions by using multiple overlapping probes.

Abstract Introduction Skull base neuroanatomy is classically taught using surgical atlases. Although these texts are critical and rich resources for learning three-dimensional (3D) relationships between key structures, we believe they could be optimized and complemented with step-by-step anatomical dissections to fully meet the learning needs of trainees. Methods Six sides of three formalin-fixed latex-injected specimens were dissected under microscopic magnification. A far lateral craniotomy was performed by each of three neurosurgery resident/fellow at varying stages of training. The study objective was the completion and photodocumentation of the craniotomy to accompany a stepwise description of the exposure to provide a comprehensive, intelligible, and anatomically oriented resource for trainees at any level. Illustrative case examples were prepared to supplement approach dissections. Results The far lateral approach provides a wide and versatile corridor for posterior fossa operation, with access spanning the entire cerebellopontine angle (CPA), foramen magnum, and upper cervical region. Key Steps Include The study includes the following steps: positioning and skin incision, myocutaneous flap, placement of burr holes and sigmoid trough, fashioning of the craniotomy bone flap, bilateral C1 laminectomy, occipital condyle/jugular tubercle drilling, and dural opening. Conclusion Although more cumbersome than the retrosigmoid approach, a far lateral craniotomy offers unparalleled access to lesions centered lower or more medially in the CPA, as well as those with significant extension into the clival or foramen magnum regions. Dissection-based neuroanatomic guides to operative approaches provide a unique and rich resource for trainees to comprehend, prepare for, practice, and perform complex cranial operations, such as the far lateral craniotomy.

Abstract The complex and dynamic system of fluid flow through the perivascular and interstitial spaces of the CNS has new-found implications for neurological diseases. CSF movement throughout the CNS parenchyma is more dynamic than could be explained via passive diffusion mechanisms alone. Indeed, a semistructured glial-lymphatic (glymphatic) system of astrocyte-supported extracellular perivascular channels serves to directionally channel extracellular fluid, clearing metabolites and peptides to optimize neurological function. Clinical studies of the glymphatic network have to date proven challenging, with most data gleaned from rodent models and post-mortem investigations. However, increasing evidence suggests that disordered glymphatic function contributes to the pathophysiology of CNS ageing, neurodegenerative disease and CNS injuries, as well as normal pressure hydrocephalus. Unlocking such pathophysiology could provide important avenues towards novel therapeutics. We here provide a multidisciplinary overview of glymphatics and critically review accumulating evidence regarding its structure, function and hypothesized relevance to neurological disease. We highlight emerging technologies of relevance to the longitudinal evaluation of glymphatic function in health and disease. Finally, we discuss the translational opportunities and challenges of studying glymphatic science.

While virtual surgical planning (VSP) and three-dimensional planning (3DP) have become important tools in acute craniomaxillofacial surgery, the incorporation of point of care VSP and 3DP is crucial to allow for acute facial trauma care. In this article, we review our approach to acute craniomaxillofacial trauma management, EPPOCRATIS, and discuss current challenges and future directions in acute facial trauma management.

Objective: Contour irregularities in the temporal region have been reported previously after procedures involving temporal dissection. In this study, we report paradoxical temporal enlargement (PTE) following interfascial pterional craniotomy. Methods: A retrospective review of patients who underwent a unilateral transcranial procedure with frontotemporal approach at our institution between September 2013 and December 2017 was performed. Patients with a previous craniotomy or bilateral craniotomy were excluded. Radiological imaging series including computed tomography and magnetic resonance imaging were utilized to calculate temporal soft tissue volumes both preoperatively and postoperatively by using advanced software technology. Relative soft tissue volume differences between the operative side and the contralateral side were calculated at different time-points including preoperative, 3-months follow-up (3M), 12-months (12M) follow-up, and the last follow-up (LFU, over 1-year). Results: Forty-three patients were included. Mean age was 52.7 ± 4.5 years. Mean follow-up was 27.9 ± 15.8 months. Significant changes of temporal fat pad relative-volume difference were observed between the preoperative and the corresponding 3M (t [82] = −2.8865, P = 0.0050); 12M (t [77] = −4.4321, P < 0.0001), and LFU (t [74] = −4.9862, P < 0.0001) postoperative time points. No significant change of the temporalis muscle was observed between the preoperative and the corresponding 3M (P = 0.3629), 12M (P = 0.1553), or LFU (P = 0.0715). Soft tissue volume showed a significant increase on the operative side between the preoperative and the corresponding LFU (t [74] = −2.5866, P = 0.0117). Conclusions: Paradoxical temporal enlargement with more than 10% volumetric change was observed in 24% of the patients at their LFU (>1-year). This change was not due to temporalis muscle changes. Paradoxical temporal enlargement was due to hypertrophy of the superficial temporal fat pad. Before surgical correction of postoperative temporal contour changes, it is important to obtain imaging and characterize the etiology of the deformity.

12086 Background: Patients with bone metastases may experience pain and decreased quality of life. Standard of care therapies such as radiation therapy could take weeks for pain relief and carry a risk of radiation induced fracture. Minimally invasive percutaneous radiofrequency ablation (RFA) have been shown in small observational studies to be an alternative treatment for bone metastases. We report the results of the OPuS One trial evaluating RFA for the palliative treatment of patients with painful bone metastases. Methods: OPuS One (NCT03249584) was a multicenter prospective trial. 218 subjects with painful bone metastases (≥ 4/10 worst pain scores, Brief Pain Inventory [BPI], at target treated site) were enrolled from 15 sites. RFA was performed under image guidance at one or two locations. Vertebral augmentation was followed based on physician’s discretion. Subjects’ pain (BPI) and quality of life (EQ-5D) scores were calculated in subjects at three days, one week, and one, three, six, and 12 months post RFA. Rate of complete (0 pain score at treated site with no concomitant analgesic increase) and partial responders (≥ 2 pain score reduction without analgesic increase or analgesic reduction of ≥ 25% from baseline) were calculated. Device-, procedure-, and/or therapy-related adverse events (AEs) were collected. Results: 206 subjects, 113 (55%) female and 93 (45%) males (mean age was 63.7 years) were treated with RFA. Most common primary cancers were breast (23%), lung (23%), and kidney (10%). 184 (89%) subjects were treated for metastatic lesions involving the thoracolumbar spine and 22 (11%) subjects were treated for iliac crest, periacetabulum, sacrum or mixed vertebral and pelvic location. 99% (262/264) of RFA procedures were technically successful and 97% were followed by vertebral augmentation. Subjects reported significant improvement in worst pain from baseline at 7.8 to 5.5, 4.7, 3.6, 3.2, 2.4, and 2.6 at three days, one week and one, three, six, and 12 months post RFA, respectively (p < 0.0001 for all visits). Significant improvements were also seen in average pain (p < 0.0001 for all visits), pain interference (p < 0.0001 for all visits), and quality of life scores (p < 0.0001 for all visits). Overall response rates were 53%, 58%, 61%, 63%, 70%, and 75% at three days, one week, one month, three months, six months, and twelve months post RFA, respectively. Six AEs were reported with three as serious: intra-abdominal fluid collection, pneumonia and respiratory failure. 82 deaths were reported during the study, none were related to the device, therapy, and/or procedure. No skeletal related events were reported. Conclusions: In a large prospective multicenter trial, OPuS One, RFA provided rapid, significant, and durable improvements in pain relief and quality of life up to 12 months. Clinical trial information: NCT03249584.