Middle meningeal artery embolization for symptomatic chronic subdural hematoma in the setting of severe transfusion-refractory thrombocytopenia: A case study and review of literature.

Background: Surgical decompression for the treatment of chronic subdural hematomas (cSDHs) is irrefutably effective; however, its utility in managing cSDH in patients with comorbid coagulopathy remains controversial. The optimal threshold for platelet transfusion in cSDH management is <100,000/mm3, according to guidelines from the American Association of Blood Banks GRADE framework. This threshold may be unachievable in refractory thrombocytopenia, though surgical intervention may still be warranted. We present a patient with symptomatic cSDH and transfusion-refractory thrombocytopenia successfully treated with middle meningeal artery embolization (eMMA). We also review the literature to identify management approaches for cSDH with severe thrombocytopenia. Case Description: A 74-year-old male with acute myeloid leukemia presented to the emergency department with persistent headache and emesis following fall without head trauma. Computed tomography (CT) revealed a 12 mm right-sided, mixed density SDH. Platelets were <2000/mm3 initially, which stabilized to 20,000 following platelet transfusions. He then underwent right eMMA without surgical evacuation. He received intermittent platelet transfusions with platelet goal >20,000 and was discharged on hospital day 24 with resolving SDH on CT. Conclusion: High-risk surgical patients with refractory thrombocytopenia and symptomatic cSDH may be successfully treated with eMMA without surgical evacuation. A platelet goal of 20,000/mm3 before and following surgical intervention proved beneficial for our patient. Similarly, a literature review of seven cases of cSDH with comorbid thrombocytopenia revealed five patients undergoing surgical evacuation following initial medical management. Three cases reported a platelet goal of 20,000. All seven cases resulted in stable or resolving SDH with platelets >20,000 at discharge.

Themes in neuronavigation research: A machine learning topic analysis.

Objective: To understand trends in neuronavigation we employed machine learning methods to perform a broad literature review which would be impractical by manual inspection. Methods: PubMed was queried for articles with "Neuronavigation" in any field from inception-2020. Articles were designated neuronavigation-focused (NF) if "Neuronavigation" was a major MeSH. The latent dirichlet allocation topic modeling technique was used to identify themes of NF research. Results: There were 3896 articles of which 1727 (44%) were designated as NF. Between 1999-2009 and 2010-2020, the number of NF publications experienced 80% growth. Between 2009-2014 and 2015-2020, there was a 0.3% decline. Eleven themes covered 1367 (86%) NF articles. "Resection of Eloquent Lesions" comprised the highest number of articles (243), followed by "Accuracy and Registration" (242), "Patient Outcomes" (156), "Stimulation and Mapping" (126), "Planning and Visualization" (123), "Intraoperative Tools" (104), "Placement of Ventricular Catheters" (86), "Spine Surgery" (85), "New Systems" (80), "Guided Biopsies" (61), and "Surgical Approach" (61). All topics except for "Planning and Visualization", "Intraoperative Tools", and "New Systems" exhibited a monotonic positive trend. When analyzing subcategories, there were a greater number of clinical assessments or usage of existing neuronavigation systems (77%) rather than modification or development of new apparatuses (18%). Conclusion: NF research appears to focus on the clinical assessment of neuronavigation and to a lesser extent on the development of new systems. Although neuronavigation has made significant strides, NF research output appears to have plateaued in the last decade.

Cerebral toxoplasmosis in a patient with combined variable immunodeficiency.

Background: Cerebral toxoplasmosis is an opportunistic infection in patients but has rarely been described in the setting of compromised humoral immunodeficiency. Prompt diagnosis and treatment of the infection is critical in the care of these patients. Medical management is the mainstay of treatment of the infection. There have been very few reports of surgical management of cerebral toxoplasmosis. Case Description: We describe the case of a 40-year-old male who presented with headache, memory deficits, weight loss, and left-sided weakness in the setting of a known but undiagnosed brain lesion identified 1 month prior. Imaging demonstrated a right basal ganglia lesion which was initially presumed to be malignancy. On further workup including a positive serum test and biopsy including polymerase chain reaction analysis, diagnosis was confirmed as toxoplasmosis. On further investigation, he was found to have deficiencies in immunoglobulins consistent with common variable immunodeficiency (CVID). The patient underwent craniotomy with surgical debulking as repeat imaging showed increased size of mass with new satellite lesions and worsening hydrocephalus. Conclusion: Cerebral toxoplasmosis is an important differential to consider in cases of intracerebral lesions and should not necessarily be excluded in the absence of compromised cellular immunity. In cases where there is no immunocompromised state and malignancy cannot immediately be established, CVID should be considered as an etiology. Due to the subtlety of CVID diagnosis, careful attention should be paid to history taking and workup for CVID should be considered as soon as possible. Surgical removal of these lesions in conjunction with medications is an effective treatment option.

Deep neural networks allow expert-level brain meningioma segmentation and present potential for improvement of clinical practice.

Accurate brain meningioma segmentation and volumetric assessment are critical for serial patient follow-up, surgical planning and monitoring response to treatment. Current gold standard of manual labeling is a time-consuming process, subject to inter-user variability. Fully-automated algorithms for meningioma segmentation have the potential to bring volumetric analysis into clinical and research workflows by increasing accuracy and efficiency, reducing inter-user variability and saving time. Previous research has focused solely on segmentation tasks without assessment of impact and usability of deep learning solutions in clinical practice. Herein, we demonstrate a three-dimensional convolutional neural network (3D-CNN) that performs expert-level, automated meningioma segmentation and volume estimation on MRI scans. A 3D-CNN was initially trained by segmenting entire brain volumes using a dataset of 10,099 healthy brain MRIs. Using transfer learning, the network was then specifically trained on meningioma segmentation using 806 expert-labeled MRIs. The final model achieved a median performance of 88.2% reaching the spectrum of current inter-expert variability (82.6-91.6%). We demonstrate in a simulated clinical scenario that a deep learning approach to meningioma segmentation is feasible, highly accurate and has the potential to improve current clinical practice.

Biopsy Artifact in Laser Interstitial Thermal Therapy: A Technical Note.

PURPOSE: The safety and effectiveness of laser interstitial thermal therapy (LITT) relies critically on the ability to continuously monitor the ablation based on real-time temperature mapping using magnetic resonance thermometry (MRT). This technique uses gradient recalled echo (GRE) sequences that are especially sensitive to susceptibility effects from air and blood. LITT for brain tumors is often preceded by a biopsy and is anecdotally associated with artifact during ablation. Thus, we reviewed our experience and describe the qualitative signal dropout that can interfere with ablation. METHODS: We retrospectively reviewed all LITT cases performed in our intraoperative MRI suite for tumors between 2017 and 2020. We identified a total of 17 LITT cases. Cases were reviewed for age, sex, pathology, presence of artifact, operative technique, and presence of blood/air on post-operative scans. RESULTS: We identified six cases that were preceded by biopsy, all six had artifact present during ablation, and all six were noted to have air/blood on their post-operative MRI or CT scans. In two of those cases, the artifactual signal dropout qualitatively interfered with thermal damage thresholds at the borders of the tumor. There was no artifact in the 11 non-biopsy cases and no obvious blood or air was noted on the post-ablation scans. CONCLUSION: Additional consideration should be given to pre-LITT biopsies. The presence of air/blood caused an artifactual signal dropout effect in cases with biopsy that was severe enough to interfere with ablation in a significant number of those cases. Additional studies are needed to identify modifying strategies.

Primary Spontaneous Inferior Clival Cerebrospinal Fluid Leak.

Primary, spontaneous cerebrospinal fluid (CSF) leaks secondary to defects in the clivus are exceedingly rare. Additionally, primary, spontaneous CSF leaks are typically present in obese women with idiopathic intracranial hypertension (IIH). In the present study, we report the first case of a primary, spontaneous CSF leak in the inferior-posterior wall of the clivus in an atypical patient with a BMI of 18.9 kg/m2 without IIH. Accurate diagnoses of CSF leaks are imperative in the context of preventing meningitis, and delays in diagnosis and treatment are associated with worse outcomes. Improved characterization of rare, spontaneous CSF leaks may prove beneficial in correctly diagnosing affected patients.

Bone Marrow Aspirate in Spine Surgery: Case Series and Review of the Literature.

Background With the modernization of biotechnology, there has been a concerted effort to create novel biomaterials to promote arthrodesis for spine surgery. The novel use of the stem cells from bone marrow aspirate (BMA) to augment spine surgery is a burgeoning field because these cells are considered to be both osteoinductive and osteogenic. We sought to review the evidence behind the use of BMAs in spinal fusions and report the results of our own case series. Methods PubMed and EMBASE databases were searched for studies that investigated the use of stem cells for spine surgery. For our own case series, the medical records of 150 consecutive patients who underwent a lumbar spinal fusion with BMA were retrospectively reviewed for adverse events (AEs) for up to two years after surgery. Results In our case series, there were no AEs identified in 49% of our patients. Of the identified AEs, 61% were unrelated to the use of BMA (e.g., UTI and heart failure), with the remaining 39% likely unrelated to its use (e.g., back pain and anemia). There was a 92.8% arthrodesis rate with the use of BMA. Conclusions We reviewed the rationale, basic science, and clinical science for BMA usage in spine surgery and concluded that BMA is safe for use in spine surgery and is associated with a high rate of arthrodesis.

Intraoperative Imaging for High-Grade Glioma Surgery.

This article discusses intraoperative imaging techniques used during high-grade glioma surgery. Gliomas can be difficult to differentiate from surrounding tissue during surgery. Intraoperative imaging helps to alleviate problems encountered during glioma surgery, such as brain shift and residual tumor. There are a variety of modalities available all of which aim to give the surgeon more information, address brain shift, identify residual tumor, and increase the extent of surgical resection. The article starts with a brief introduction followed by a review of with the latest advances in intraoperative ultrasound, intraoperative MRI, and intraoperative computed tomography.

Nitrous oxide-induced demyelination: Clinical presentation, diagnosis and treatment recommendations.

BACKGROUND: Recreational use of nitrous oxide (NO) in the general public has led to increasing reports of NO-induced demyelination (NOID). We describe the varying clinical presentations and pathophysiology, and offer a treatment paradigm. METHODS: A literature search of MEDLINE and EMBASE resulted in 42 publications with 37 studies meeting the inclusion criteria, for a total of 51 patients. Our case series included 5 patients seen from 2014 to 2018 followed over 3-60 months. RESULTS: Those with sensory symptoms and subjective weakness were categorized as having "mild" symptoms (25%). Symptoms indicating involvement outside the dorsal columns such as observer-graded weakness were categorized as "moderate" (61%). Patients with the aforementioned plus cognitive effects were categorized as "severe" (12%). There was no dose-dependent relationship between the amount of NO used and clinical impairment. There was a trend between the severity of neurologic impairment and serum levels of B12. Two patients were noncompliant. One initiated only oral therapy and did not improve. One received injections a month apart and worsened. CONCLUSIONS: Patients with NOID tend to have worse symptoms when presenting with lower serum vitamin B12 levels and have good recovery rates when treated with intramuscular B12 and oral supplementation.

SlicerDMRI: Diffusion MRI and Tractography Research Software for Brain Cancer Surgery Planning and Visualization.

PURPOSE: We present SlicerDMRI, an open-source software suite that enables research using diffusion magnetic resonance imaging (dMRI), the only modality that can map the white matter connections of the living human brain. SlicerDMRI enables analysis and visualization of dMRI data and is aimed at the needs of clinical research users. SlicerDMRI is built upon and deeply integrated with 3D Slicer, a National Institutes of Health-supported open-source platform for medical image informatics, image processing, and three-dimensional visualization. Integration with 3D Slicer provides many features of interest to cancer researchers, such as real-time integration with neuronavigation equipment, intraoperative imaging modalities, and multimodal data fusion. One key application of SlicerDMRI is in neurosurgery research, where brain mapping using dMRI can provide patient-specific maps of critical brain connections as well as insight into the tissue microstructure that surrounds brain tumors. PATIENTS AND METHODS: In this article, we focus on a demonstration of SlicerDMRI as an informatics tool to enable end-to-end dMRI analyses in two retrospective imaging data sets from patients with high-grade glioma. Analyses demonstrated here include conventional diffusion tensor analysis, advanced multifiber tractography, automated identification of critical fiber tracts, and integration of multimodal imagery with dMRI. RESULTS: We illustrate the ability of SlicerDMRI to perform both conventional and advanced dMRI analyses as well as to enable multimodal image analysis and visualization. We provide an overview of the clinical rationale for each analysis along with pointers to the SlicerDMRI tools used in each. CONCLUSION: SlicerDMRI provides open-source and clinician-accessible research software tools for dMRI analysis. SlicerDMRI is available for easy automated installation through the 3D Slicer Extension Manager.

Intraclass Correlations of Measured Magnetic Resonance Imaging Volumes of Laser Interstitial Thermal Therapy-Treated High-Grade Gliomas.

BACKGROUND AND OBJECTIVES: Laser interstitial thermal therapy (LITT) is a minimally invasive therapeutic option for the treatment of brain tumors. Previous studies have quantitatively followed the ablated volumes of high-grade gliomas. Reported treatment volumes range from 28% to 100%, with no reported interobserver analysis. Because these volumes are subjectively measured, it is necessary to establish concordance between clinicians. STUDY DESIGN/MATERIALS AND METHODS: Utilizing Brainlab tumor analysis software (Brainlab, Munich, Germany), five physician users traced out tumor volumes slice-by-slice on 10 treated tumors in eight patients. The participants were briefed with specific instructions and a demonstration on how to trace the enhancing borders of the tumor slice-by-slice. Volumes automatically calculated by the Brainlab software included preoperative, intraoperative ablation and postoperative enhancing volumes. Data regarding size, cystic appearance, pathology, previous surgery, and demographics were included. RESULTS: The intraclass correlation coefficient (ICC) for preoperative, intraoperative, and postoperative volumes was 0.92 (95% confidence interval, [CI] 0.81-0.97), 0.90 (0.77-0.96), and 0.89 (0.74-0.96), respectively. The overall ICC was 0.72 (0.50-0.87). ICC comparisons were also made for each pair of readers (neuroradiologist, neuro-oncologist, senior neurosurgery resident, neurosurgery junior resident) which resulted in pretreatment ICC scores of 0.97, 0.91, 0.66, 0.94; intratreatment scores of 0.97, 0.78, 0.90, 0.96; and posttreatment scores of 0.96, 0.81, 0.89, and 0.87. A Bland-Altman plot was also used to assess the differences in volumes. CONCLUSIONS: The ICC gives a composite of the consistency of measurements made by multiple observers measuring the same quantity. The overall ICC of 0.72 means there is good correlation between observers in our study between measured volumes. Lasers Surg. Med. © 2019 Wiley Periodicals, Inc.

Treatment of a Staphylococcus lugdunensis cervical epidural abscess.

First reported in 1988, Staphylococcus lugdunensis is a virulent coagulase-negative Staphylococcus species often associated with endocarditis. This is the first case report describing this infection in the cervical spine. A 58-year-old, left-handed Caucasian woman with no significant medical history presented with neck and left arm pain. Neurological examination revealed mild left deltoid 4/5 weakness and myelopathy. She was found to have an epidural cervical spinal cord mass that was causing severe cord compression and underwent partial anterior cervical decompression of the mass. On entering what was believed to be the mass, yellow-tinged fluid was encountered. An abscess was immediately suspected, so the dura was not entered. The specimen sent for culture was identified a day later as S. lugdunensis A two-dimensional echocardiogram was negative for vegetations. A peripherally inserted central catheter line was placed and the patient discharged on 6 weeks of physical therapy and 6-8 weeks of intravenous cefazolin.

Pediatric intramedullary spinal cord tumor outcomes using the WeeFIM scale.

PURPOSE: The Functional Independence Measure for children (WeeFIM) is a user-friendly functional outcomes tool that has been validated across other traditional functional scales. Historically, the significant neurologic and functional deficits of intramedullary spinal cord tumors (IMSCTs) have been monitored by coarse or overbearing functional outcomes tools that make it difficult to measure the slow improvement/decline seen in these patients. This study is the first to report WeeFIM outcomes on a series of IMSCTs with emphasis on an aggressive surgical strategy. METHODS: A retrospective review from 2005 to 2014 was performed for nine patients who underwent resective surgery for intramedullary spinal cord tumors with intraoperative ultrasound and neurophysiologic monitoring. WeeFIM scales were assessed at admission and discharge to evaluate changes in severity of disability and need for assistance. RESULTS: At the time of this submission, 7/9 patients are alive. The mean WeeFIM improvement was 27 points (8-50 points) with a mean WeeFIM efficiency of 2.0 points/day. CONCLUSIONS: The WeeFIM scale is an appropriate and useful scale for measuring postoperative improvements in patients with IMSCTs undergoing aggressive resective surgery. Attention to intraoperative spinal cord monitoring and prevention of spinal column instability may prevent morbidity related to surgery, and functional outcomes do not appear to be compromised by an aggressive surgical approach.

Brain metastasis: clinical manifestations, symptom management, and palliative care.

Patients who have brain metastases can suffer from a medley of symptoms, including headaches, seizures, cognitive impairment, fatigue, and focal deficits. As therapies have evolved, so has the management of these symptoms as patients survive longer. This chapter focuses on the clinical presentation of brain metastases, the treatment of those symptoms, and palliation in end-of-life management. Brain metastases are the most common cerebral malignancy. They can present with various symptoms, which can have significant impact on patients' quality of life throughout the course of their disease. Most of these symptoms are related to direct brain compression from the tumor or from edema. The location of the metastases will determine the focal deficits incurred and most patients will be on a course of steroids tapered according to their clinical status. The chapter includes a list of potential side-effects and considerations for management. Palliative care is an essential and important part of approaching patients with metastases. Early and clear communication about end-of-life decision making is encouraged with multiple easily accessible tools. For patients near the end of life, comfort is the ultimate goal in providing a good quality of life.

Intraoperative Raman Spectroscopy.

Surgical excision of brain tumors provides a means of cytoreduction and diagnosis while minimizing neurologic deficit and improving overall survival. Despite advances in functional and three-dimensional stereotactic navigation and intraoperative MRI, delineating tissue in real time with physiologic confirmation is challenging. Raman spectroscopy has potential to be an important modality in the intraoperative evaluation of tissue during surgical resection. In vitro experimental studies have shown that this technique can be used to differentiate normal brain tissue from tissue with infiltrating cancer cells and dense cancerous masses with high specificity, indicating the feasibility of this method for in vivo application.

A case of symptomatic spinal dural arteriovenous fistula after high-volume lumbar puncture.

BACKGROUND: Spinal dural arteriovenous fistulas (DAVFs) are rare lesions that lead to venous congestion and ischemic injury resulting in neurologic deterioration. Here we present a patient diagnosed with glioblastoma multiforme (GBM) who became symptomatic from a spinal DAVF after a diagnostic high-volume lumbar puncture (LP). CASE DESCRIPTION: When a 72-year-old female developed partial seizures in her left upper extremity without other focal neurological deficits, she underwent a magnetic resonance imaging (MRI) scan of the brain. The MRI revealed a right frontal/posterior corpus callosal lesion. She next had a MR-guided high-volume LP. A GBM was diagnosed following a biopsy. Postoperatively, after the LP, she was noted to have bilateral deltoid and bilateral 4/5 lower extremity weakness, with diffuse hyperreflexia. The MRI and magnetic resonance angiogram (MRA) of the cervical spine demonstrated a large venous varix at the C5-C6 level within the left neural foramen. She underwent successful complete embolization of two thyrocervical branches with direct communication to an enlarged anterior spinal artery. One month later, her neurological examination returned to baseline; she was walking independently with only 4+/5 residual weakness in her left lower extremity. CONCLUSIONS: Here we report a patient with a cranial GBM and an incidental cervical spinal C5-C6 DAVF that became symptomatic after a high-volume LP. It is possible that the high-volume LP increased vascular congestion, thus precipitating the onset of cervical myelopathy.

A novel technique to repair a transverse sacral fracture in a previously fused lumbosacral spondylolisthesis.

BACKGROUND: Transverse fractures of the sacrum are rare, and surgical treatment for these fractures ranges from conservative to challenging. Transverse stress fractures of the sacrum after placement of lumbar-to-sacral instrumentation have been previously described. We report a new technique to repair a transverse Type-2 Roy-Camille fracture with spondylolisthesis of S1 over S2 in a previously fused instrumented high-grade L4-L5, L5-S1 spondylolisthesis. CASE DESCRIPTION: A 64-year-old female who previously had an L4-L5, L5-S1 fusion for spondylolisthesis presented with excruciating lower back pain and radiculopathy for over 6 months. She was found to have an S1-S2 transverse fracture caused by previous implantation of pedicle screws. She underwent repositioning of several failed right lumbar and sacral screws and then had bilateral S1-S2 screws placed directly across the fracture line. The patient had an unremarkable postoperative course. She discontinued most of her pain medications within 6 weeks postoperatively. In the months following surgery, she reported only minimal lower back pain and no radiculopathy with the last appointment 5 years postoperatively. CONCLUSIONS: We describe a novel technique to reduce an iatrogenic transverse type-2 Roy-Camille fracture at S1-S2 in a previously instrumented high-grade L4-L5, L5-S1 spondylolisthesis. The patient's fracture achieved adequate reduction and fusion with symptomatic relief.

Shining light on neurosurgery diagnostics using Raman spectroscopy.

Surgical excision of brain tumors provides a means of cytoreduction and diagnosis while minimizing neurologic deficit and improving overall survival. Despite advances in functional and three-dimensional stereotactic navigation and intraoperative magnetic resonance imaging, delineating tissue in real time with physiological confirmation is challenging. Raman spectroscopy is a promising investigative and diagnostic tool for neurosurgery, which provides rapid, non-destructive molecular characterization in vivo or in vitro for biopsy, margin assessment, or laboratory uses. The Raman Effect occurs when light temporarily changes a bond's polarizability, causing change in the vibrational frequency, with a corresponding change in energy/wavelength of the scattered photon. The recorded inelastic scattering results in a "fingerprint" or Raman spectrum of the constituent under investigation. The amount, location, and intensity of peaks in the fingerprint vary based on the amount of vibrational bonds in a molecule and their ensemble interactions with each other. Distinct differences between various pathologic conditions are shown as different intensities of the same peak, or shifting of a peak based on the binding conformation. Raman spectroscopy has potential for integration into clinical practice, particularly in distinguishing normal and diseased tissue as an adjunct to standard pathologic diagnosis. Further, development of fiber-optic Raman probes that fit through the instrument port of a standard endoscope now allows researchers and clinicians to utilize spectroscopic information for evaluation of in vivo tissue. This review highlights the need for such an instrument, summarizes neurosurgical Raman work performed to date, and discusses the future applications of neurosurgical Raman spectroscopy.

Barriers to healthcare of homeless residents of three Honolulu shelters.

In Honolulu, health insurance rates amongst the homeless are one of the highest in the nation, yet significant health care needs are still unmet. In a previous model, health care barriers have been divided into four domains: bureaucratic, personal, programmatic, and financial. This study aimed to determine the risk factors associated with the domains of health care barriers amongst the study's sample of 128 subjects across three Honolulu homeless shelters. Univariate models revealed health care barriers; but only the lack of health insurance was a significant financial barrier to health care in multivariate analyses (Odds ratio: 2.12; 95% Confidence Interval: 1.09-4.16). The identification of barriers should guide how health care programs approach Honolulu's homeless population to better serve their health care needs.