Advances in Cranial Surgery.

The landscape of the cranial neurosurgery has changed tremendously in past couple of decades. The main frontiers including introduction of neuro-endoscopy, minimally invasive skull base approaches, SRS, laser interstitial thermal therapy and use of tubular retractors have revolutionized the management of intracerebral hemorrhages, deep seated tumors other intracranial pathologies. Introduction of these novel techniques is based on smaller incisions with maximal operative corridors, decreased blood loss, shorter hospital stays, decreased post-operative pain and cosmetically appealing scars that improves patient satisfaction and clinical outcomes. The sophisticated tools like neuroendoscopy have improved light source, and better visualization around the corners. Advanced navigated tools and channel-based retractors help us to target deeply seated lesions with increased precision and minimal disruption of the surrounding neurovascular tissues. Advent of stereotactic radiosurgery has provided us alternative feasible, safe and effective options for treatment of patients who are otherwise not medically stable to undergo complex cranial surgical interventions. This paper review advances in treatment of intracranial pathologies, and how the neurosurgeons and other medical providers at the University of Missouri-Columbia (UMC) are optimizing these treatments for their patients.

The Risk of Adverse Events in Smokers Undergoing Spinal Fusion: A Systematic Review and Meta-Analysis.

STUDY DESIGN: Systematic review and meta-analysis. OBJECTIVES: Determine if tobacco use is associated with increased risk of postoperative adverse events within 90 days in patients undergoing spinal fusion surgery. METHODS: Databases were queried to identify cohort studies that directly compared smokers with non-smokers and provided the absolute number of adverse events and the population at risk. Data quality was evaluated using the Quality in Prognosis Studies tool. Risk ratios (RR) and 95% confidence intervals were calculated and compared between studies. The grading of recommendation, assessment, development and evaluation (GRADE) criteria were used to assess the strength of the evidence. RESULTS: Seventeen studies assessing 37 897 participants met the inclusion criteria. Of these, 10 031 (26.5%) were smokers and 27 866 (73.5%) were nonsmokers. The mean age for the study population was 58 years, and 45% were males. Smoking was not associated with increased risk of one or more major adverse events within 90 days following spine surgery (seven studies, pooled RR 1.13, 95% CI [.75-1.71], I2 = 41%). However, smoking was significantly associated with one or more major adverse events in ≤2 level fusion (three studies, pooled RR 2.46, 95% CI [1.18-5.12], I2 = 0%), but not in fusions of ≥3 levels (four studies, pooled RR .87, 95% CI [.70-1.08], I2 = 0%). Additionally, there was no statistically significant association between smoking and any adverse event, nor increased reoperation risk due to adverse events. CONCLUSIONS: In this meta-analysis, tobacco use was not associated with a statistically significant increased risk of adverse events within 90 days in patients undergoing spinal fusion surgery. Our results are limited by the variable reporting methodology for both complication rates as well as smoking incidence between the included individual studies.

Chordoma of the Skull Base: A National Cancer Database Analysis of Current Practice Patterns and Outcomes.

BACKGROUND: Chordomas of the skull base are aggressive locally destructive tumors that arise from the remnants of the fetal notochord. Current guidelines recommend maximal safe surgical resection followed by adjuvant radiation therapy. However, because of the rarity of these tumors, the optimal radiotherapeutic regimen regarding dose and modality is unclear. METHODS: The National Cancer Database (NCDB) was queried from 2004 to 2016. Data from adult patients were extracted, including tumor characteristics, comorbidity indices, and details of treatment (surgery, radiation, and chemotherapy). The primary outcome of interest was overall survival (OS), which was evaluated for specific treatment cohorts using Cox univariate and multivariate regression constructs along with associated survival curves. RESULTS: We identified 798 patients with a diagnosis of skull base chordoma. Mean OS in this cohort was 9.57 years. Most patients received surgical resection (89.1%), with 53.9% receiving radiotherapy and 6.5% receiving chemotherapy. After adjusting for baseline characteristics using multivariate regression, advanced age and increased tumor size were associated with decreased OS. Surgical resection was associated with increased OS, whereas neither radiotherapy nor chemotherapy was associated with OS. However, in patients who did receive radiation, dosage >6000 cGy was associated with increased OS (hazard ratio, 0.51; P = 0.038); OS did not vary significantly between traditional and proton-based methods. CONCLUSIONS: Our multi-institutional analysis supports the use of partial and radical surgical resection to improve survival in patients with skull base chordomas. Among patients who receive radiotherapy, higher radiation dose is associated with improved survival.

Bifrontal Osteoplastic Flap: An Option to Decrease Infection in Bifrontal Craniotomies with Skull Base Osteotomies.

Infection can be a common complication following bifrontal craniotomy with skull base osteotomies given the potential violation of sinuses and entry into the nasal structures. Our objective was to examine our series of patients who underwent a bifrontal craniotomy with skull base osteotomies and describe the infection rate. We propose the bifrontal osteoplastic flap as an adjunct to infection prevention. A retrospective single-center study of a patient database was performed. Twenty patients were identified. Fifty-five percent were male. The mean age was 55.7 ± 13.9 years. The most common indications for surgery were esthesioneuroblastomas (35%) and anterior skull base meningiomas (30%). Six patients (30%) developed an infection, 1 patient (5%) developed a CSF leak, and no patients developed a mucocele. All 6 infected cases had nasal pathology with intracranial extension, they all received chemoradiation post-operatively and were all combined cases with otorhinolaryngology. Eighty-three percent of these patients required a craniectomy and all of them required long-term IV antibiotics. Infection is not uncommon after a bifrontal craniotomy with skull base osteotomies and the use of the bifrontal osteoplastic flap in cases where the risk of infection is high, i.e., esthesioneuroblastomas surgery, may help reduce said risk and lead to better patient outcomes.

Temporal Evolution of Hypertrophic Olivary Degeneration in a Pediatric Patient: A Case Report and Review of Literature.

Hypertrophic olivary degeneration (HOD) is a rare type of neuronal degeneration seen after interruption of the dentato-rubro-olivary tract also known as the Guillain-Mollaret triangle (GMT). It is associated with hypertrophic changes of the inferior olive. Commonly reported in adults, this lesion presents with ataxia and oculopalatal myoclonus. Up to date, few cases have been published in the literature that refer to pediatric cases. This diagnosis is particularly important in the setting of brainstem tumor surgery as it should not be confused for tumor recurrence or metastasis, in turn avoiding unwarranted surgical intervention. We present the case of a 15-year-old male who underwent resection of a left superior cerebellar peduncle (SCP) pilocytic astrocytoma. On follow-up, magnetic resonance imaging (MRI) demonstrated evidence of mild residual tumor as well as progressive engorgement of the inferior olivary nucleus (ION). The patient was clinically asymptomatic and has since been observed expectantly without any issues. We were able to pinpoint the most probable location of injury in our patient's GMT. HOD remains a somewhat obscure entity. Its presentation may be early and not accompanied by significant neurologic findings, in contrast to what has been previously reported. Particularly in neoplastic cases, it may represent a diagnostic challenge and could be easily confused for tumor recurrence. A multidisciplinary approach for this entity, as with other pathologies, is of particular importance. Its proper recognition will result in the best outcomes for the patient.

Retrospective Data Analysis and Literature Review for a Development of Enhanced Recovery after Surgery Pathway for Anterior Cervical Discectomy and Fusion.

Objective While enhanced recovery after surgery (ERAS) protocols are associated with shorter length of stay and improved outcomes in multiple surgical specialties, its application to spine surgery has been limited. Anterior cervical discectomy and fusion (ACDF) is a common spinal procedure with a relative efficacy and safety profile that makes it suitable for the application of ERAS principles. Reviewing our outcomes and practice and incorporating evidence-based clinical studies, we propose the development of an ERAS pathway for ACDF. Methods This is a retrospective review of ACDF cases performed at a single institution by a single surgeon from 2014 to 2017. Primary outcome measures included length of stay, complications, and 30-day readmission rates. The 1- and 2-level and the 3- and 4-level groups were also each consolidated into a single cohort for comparison. A comprehensive review of evidence-based literature pertaining to ACDF was then performed. Best-practice recommendations derived from the literature were incorporated into the proposed ERAS protocol. Results In this series of 75 1-level, 77 2-level, 44 3-level and 20 4-level ACDF procedures, the average surgical time (minutes) was 68, 90, 118 and 141; length of stay (days) was 1, 1, 1.4, and 1.7; drain usage (%) was 1.3, 2.6, 13.6 and 10; and 30-day readmission rates (%) were 2.7, 3.9, 4.5, and 15, respectively. Combining the 1- and 2-level as a single group and 3- and 4-level as another cohort, the 3- and 4-level cohort had a significantly higher rate of drain usage and estimated blood loss (EBL) but there was not a difference in length-of-stay, complications or 30-day readmission rates. Conclusions Given the relative equivalent safety profile between 1- and 2-level as compared to 3- and 4-level ACDF, the proposed ERAS pathway can be applied to all patients, and not just restricted to 1-level or 2-level ACDF. Taking into account feasibility parameters as deduced from a review of institutional outcomes, this pathway can streamline same-day discharge and improve the patient experience. Its success will be predicated on an iterative improvement process deriving from optimal prospective outcome measurements.

Intra-Arterial Dantrolene for Refractory Cerebral Vasospasm in Patients with Aneurysmal Subarachnoid Hemorrhage.

BACKGROUND: Dantrolene has a safe side-effect profile and a mechanism of action that makes it attractive as an option for treatment of cerebral vasospasm. The authors report 2 cases of refractory cerebral vasospasm secondary to aneurysmal subarachnoid hemorrhage that were successfully treated with intra-arterial (IA) dantrolene. CASE DESCRIPTION: Two patients, a 63-year-old woman and 36-year-old woman, developed severe vasospasm refractory to IA vasodilators after rupture of anterior communicating artery aneurysms. IA dantrolene was injected in doses of 15-30 mg in the affected distributions and mean arterial pressure, intracranial pressure, and heart rate were monitored. There was immediate improvement in lumen diameter of the affected vessels following dantrolene injection. No significant differences in mean arterial pressure or intracranial pressure before and after IA dantrolene were observed. Both patients demonstrated clinical improvement within 24 hours without any further deterioration during the rest of their admission. Follow-up angiography 48 hours after IA dantrolene treatment demonstrated continued resolution of cerebral vasospasm. CONCLUSIONS: This evidence suggests IA dantrolene as a safe and effective novel alternative for the treatment of cerebral vasospasm.

Middle Cranial Fossa Approach to Repair Tegmen Defects with Autologous or Alloplastic Graft.

BACKGROUND: Temporal bone tegmen defects may be associated with cerebrospinal fluid (CSF) otorrhea. A variety of techniques have been used for repair. We report our experience with skull base reconstruction for tegmen defects using either autologous or alloplastic grafts. METHODS: A retrospective chart review was performed on patients with tegmen defects treated from 2007 to 2017 at the University Hospital in Columbia, Missouri, USA. Primary outcome measures were analyzed. RESULTS: Twenty-five patients were treated with a middle cranial fossa approach (median age 53, 88% females, median body mass index 34, median follow-up 9 months). Presenting symptoms included CSF leak (92%), hearing loss (44%), imbalance (12%), meningitis (12%), headache (4%), and tinnitus (4%). Most tegmen defects occurred spontaneously (84%) but cholesteatomas (4%), and trauma (12%) also were identified. Pre- and postoperative audiograms were available for 13 patients (52%); 7 (54%) showed objective improvement. Fourteen patients were repaired with autologous bone graft (56%), 7 with alloplastic grafts (28%), and 4 with temporalis fascia only (16%). All patients had resolution of CSF leak. Two patients (8%) suffered wound infections and 3 (12%) had facial and/or petrosal nerve complications. Use of alloplastic graft significantly shortened operative time (allopathic mean 180 minutes vs. autologous mean 208 minutes; P = 0.03). CONCLUSIONS: CSF otorrhea due to tegmen defects can be repaired via a middle fossa craniotomy using either an autologous or alloplastic graft with equivalent outcomes and efficacy, although alloplastic graft helps reduce operating time.