Inner Ear Breaches from Vestibular Schwannoma Surgery: Revisiting the Incidence of Otologic Injury from Retrosigmoid and Middle Cranial Fossa Approaches.

OBJECTIVE: To assess the rate of iatrogenic injury to the inner ear in vestibular schwannoma resections. STUDY DESIGN: Retrospective case review. SETTING: Multiple academic tertiary care hospitals. PATIENTS: Patients who underwent retrosigmoid or middle cranial fossa approaches for vestibular schwannoma resection between 1993 and 2015. INTERVENTION: Diagnostic with therapeutic implications. MAIN OUTCOME MEASURE: Drilling breach of the inner ear as confirmed by operative note or postoperative computed tomography (CT). RESULTS: 21.5% of patients undergoing either retrosigmoid or middle fossa approaches to the internal auditory canal were identified with a breach of the vestibulocochlear system. Because of the lack of postoperative CT imaging in this cohort, this is likely an underestimation of the true incidence of inner ear breaches. Of all postoperative CT scans reviewed, 51.8% had an inner ear breach. As there may be bias in patients undergoing postoperative CT, a middle figure based on sensitivity analyses estimates the incidence of inner ear breaches from lateral skull base surgery to be 34.7%. CONCLUSIONS: A high percentage of vestibular schwannoma surgeries via retrosigmoid and middle cranial fossa approaches result in drilling breaches of the inner ear. This study reinforces the value of preoperative image analysis for determining risk of inner ear breaches during vestibular schwannoma surgery and the importance of acquiring CT studies postoperatively to evaluate the integrity of the inner ear.

The unmet global burden of cranial epidural hematomas: A systematic review and meta-analysis.

OBJECTIVE: Approximately 69 million people suffer from traumatic brain injury (TBI) annually. Patients with isolated epidural hematomas (EDH) with access to timely surgical intervention often sustain favorable outcomes. Efforts to ensure safe, timely, and affordable access to EDH treatment may offer tremendous benefits. METHODS: A comprehensive literature search was conducted. A random-effects model was used to pool the outcomes. Studies were further categorized into groups by World Bank Income classification: high-income countries (HICs) and low- and middle-income countries (LMICs). RESULTS: Forty-nine studies were included, including 36 from HICs, 12 from LMICs, and 1 from HIC / LMIC. Incidence of EDH amongst TBI patients 8.2 % (95 % CI: 5.9,11.2), including 9.2 % (95 %CI 6.4,13.2) in HICs and 5.8 % (95 % CI: 3.1,10.7) in LMICs (p = 0.20). The overall percent male was 73.7 % and 47.4 % were caused by road traffic accidents. Operative rate was 76.0 % (95 %CI: 67.9,82.6), with a numerically lower rate of 74.2 % (95 %CI: 64.0,81.8) in HICs than in LMICs 82.9 % (95 %CI: 65.4,92.5) (p = 0.33). This decreased to 55.5 % after adjustment for small study effect. The non-operative mortality (5.3 %, 95 %CI: 2.2,12.3) was lower than the operative mortality (8.3 %, 95 %CI: 4.6,14.6), with slightly higher rates in HICs than LMICs. This relationship remained after adjustment for small study effect, with 9.3 % operative mortality compared to 6.9 % non-operative mortality. CONCLUSION: With an overall EDH incidence of 8.2 % and an operative rate of 55.5 %, 3.1 million people worldwide require surgery for traumatic EDH every year, most of whom are in prime working age. Given the favorable prognosis with treatment, traumatic EDH is a strong investment for neurosurgical capacity building.

Outcomes of Minimally Invasive versus Open Surgery for Intermediate to High-grade Spondylolisthesis: A 10-Year Retrospective, Multicenter Experience.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: The primary objective of our study was to evaluate the surgical outcomes and complications of minimally invasive surgery (MIS) versus open surgery in the management of intermediate to high grade spondylolisthesis, and secondarily to compare the outcomes following MIS in-situ fusion versus MIS reduction and open in-situ fusion versus open reduction subgroups. SUMMARY OF BACKGROUND DATA: High-grade spondylolisthesis is a relatively rare spine pathology with unknown prevalence. The optimal management and long-term prognosis of high-grade spondylolisthesis remain controversial. METHODS: A multicenter, retrospective cohort study of adult patients who were surgically treated for grade II or higher lumbar or lumbosacral spondylolisthesis from January 2008 until February 2019, was conducted. RESULTS: A total of 57 patients were included in this study. Forty cases were treated with open surgery and 17 with MIS. Specifically, seven patients underwent MIS in-situ fusion, 11 patients open in-situ fusion, an additional 10 patients underwent MIS reduction, and 29 had open reduction. Patients who underwent open surgery had significantly better pain relief at short-term follow-up with no statistically significant difference in the rate of complications (25% vs. 35.2%, P = 0.44), as compared with MIS. The most common complications were related to instrumentation (17.7%), followed by neurological complications (14.5%), wound infection/dehiscence (6.5%), and post laminectomy syndrome (1.6%). The average follow-up time was 9.1 ±â€Š6.2 months. In a subgroup comparison, the complication rate in the open in-situ fusion (36.3%) versus open reduction (20.6%) subgroup was non-significant (P = 0.42). However, complication rate in the MIS reduction group (55%) was significantly higher than MIS in-situ fusion (P = 0.03). CONCLUSION: MIS reduction is associated with a higher rate of complications in the management of grade II or higher lumbar or lumbosacral spondylolisthesis. The management of this complex pathology may be better addressed via traditional open surgery. LEVEL OF EVIDENCE: 3.

Quantifying the impact of surgical decompression on quality of life and identification of factors associated with outcomes in patients with symptomatic metastatic spinal cord compression.

OBJECTIVE: Metastatic spinal cord compression (MSCC) imposes significant impairment on patient quality of life and often requires immediate surgical intervention. In this study the authors sought to estimate the impact of surgical intervention on patient quality of life in the form of mean quality-adjusted life years (QALY) gained and identify factors associated with positive outcomes. METHODS: The authors performed a retrospective chart review and collected data for patients who had neurological symptoms resulting from radiologically and histologically confirmed MSCC and were treated with surgical decompression during the last 12 years. RESULTS: A total of 151 patients were included in this study (mean age 60.4 years, 57.6% males). The 5 most common metastatic tumor types were lung, multiple myeloma, renal, breast, and prostate cancer. The majority of patients had radioresistant tumors (82.7%) and had an active primary site at presentation (67.5%). The median time from tumor diagnosis to cord compression was 12 months and the median time from identification of cord compression to death was 4 months. Preoperative presenting symptoms included motor weakness (70.8%), pain (70.1%), sensory disturbances (47.6%), and bowel or bladder disturbance (31.1%). The median estimated blood loss was 500 mL and the average length of hospital stay was 10.3 days. About 18% of patients had postoperative complications and the mean follow-up was 7 months. The mean pre- and postoperative ECOG (Eastern Cooperative Oncology Group) performance status grades were 3.2 and 2.4, respectively. At follow-up, 58.3% of patients had improved status, 31.5% had no improvement, and 10.0% had worsening of functional status. The mean QALY gained per year in the entire cohort was 0.55. The mean QALY gained in the first 6 months was 0.1 and in the first year was 0.4. For patients who lived 1-2, 2-3, 3-4, or 4-5 years, the mean QALY gained were 0.8, 1.4, 1.7, and 2.3, respectively. Preoperative motor weakness, bowel dysfunction, bladder dysfunction, and ASA (American Society of Anesthesiologists) class were identified as independent predictors inversely associated with good outcome. CONCLUSIONS: The mean QALY gained from surgical decompression in the first 6 months and first year equals 1.2 months and 5 months of life in perfect health, respectively. These findings suggest that surgery might also be beneficial to patients with life expectancy < 6 months.

Microfluidic Platform to Quantify Neutrophil Migratory Decision-Making.

Neutrophils are the most abundant leukocytes in blood, serving as the first line of host defense in tissue damage and infections. Upon activation by chemokines released from pathogens or injured tissues, neutrophils migrate through complex tissue microenvironments toward sites of infections along the chemokine gradients, in a process named chemotaxis. However, current methods for measuring neutrophil chemotaxis require large volumes of blood and are often bulk, endpoint measurements. To address the need for rapid and robust assays, we engineered a novel dual gradient microfluidic platform that precisely quantifies neutrophil migratory decision-making with high temporal resolution. Here, we present a protocol to measure neutrophil migratory phenotypes (velocity, directionality) with single-cell resolution.

Visualizing virus particle mobility in liquid at the nanoscale.

Currently, there remains a critical need to develop real-time imaging resources for life sciences. Here, we demonstrate the use of high resolution in situ imaging to observe biological complexes in liquid at the nanoscale. Using a model virus system, we produced the first time-resolved videos of individual biological complexes moving in solution within an electron microscope.

A Non-Symmetric Reconstruction Technique for Transcriptionally-Active Viral Assemblies.

The molecular mechanisms by which RNA viruses coordinate their transcriptional activities are not fully understood. For rotavirus, an important pediatric gastroenteric pathogen, transcription occurs within a double-layered particle that encloses the viral genome. To date, there remains very little structural information available for actively-transcribing rotavirus double-layered particles, which could provide new insights for antiviral development. To improve our vision of these viral assemblies, we developed a new combinatorial strategy that utilizes currently available high-resolution image processing tools. First, we employed a 3D classification routine that allowed us to sort transcriptionally-active rotavirus assemblies on the basis of their internal density. Next, we implemented an additional 3D refinement procedure using the most active class of DLPs. For comparison, the refined structures were computed in parallel by (1) enforcing icosahedral symmetry, and by (2) using no symmetry operators. Comparing the resulting structures, we were able to visualize the continuum that exists between viral capsid proteins and the viral RNA for the first time.