Role of Advanced MR Imaging in Diagnosis of Neurological Malignancies: Current Status and Future Perspective.

Lesions of the central nervous system (CNS) can present with numerous and overlapping radiographical and clinical features that make diagnosis difficult based exclusively on history, physical examination, and traditional imaging modalities. Given that there are significant differences in optimal treatment protocols for these various CNS lesions, rapid and non-invasive diagnosis could lead to improved patient care. Recently, various advanced magnetic resonance imaging (MRI) techniques showed promising methods to differentiate between various tumors and lesions that conventional MRI cannot define by comparing their physiologic characteristics, such as vascularity, permeability, oxygenation, and metabolism. These advanced MRI techniques include dynamic susceptibility contrast MRI (DSC), diffusion-weighted imaging (DWI), dynamic contrast-enhanced (DCE) MRI, Golden-Angle Radial Sparse Parallel imaging (GRASP), Blood oxygen level-dependent functional MRI (BOLD fMRI), and arterial spin labeling (ASL) MRI. In this article, a narrative review is used to discuss the current trends in advanced MRI techniques and potential future applications in identifying difficult-to-distinguish CNS lesions. Advanced MRI techniques were found to be promising non-invasive modalities to differentiate between paraganglioma, schwannoma, and meningioma. They are also considered promising methods to differentiate gliomas from lymphoma, post-radiation changes, pseudoprogression, demyelination, and metastasis. Advanced MRI techniques allow clinicians to take advantage of intrinsic biological differences in CNS lesions to better identify the etiology of these lesions, potentially leading to more effective patient care and a decrease in unnecessary invasive procedures. More clinical studies with larger sample sizes should be encouraged to assess the significance of each advanced MRI technique and the specificity and sensitivity of each radiologic parameter.

Serum long non-coding RNAs as potential noninvasive biomarkers for glioblastoma diagnosis, prognosis, and chemoresistance.

Gliomas are common brain tumors with a variable prognosis based on their tumor grade. With glioblastomas, the prognosis is usually unfavorable. Thus, having accurate and rapid methods for their diagnosis and follow-up are essential for rapid discovery of the tumor and to protect patients from unnecessary procedures. Some glioma cases are challenging since there is a limited ability to differentiate between gliomas, recurrent glioblastomas, and single metastatic lesions. Monitoring treatment responses and follow-ups can also be challenging. While both radiological and serological markers have been identified that can aid diagnosis and assess therapies, a particularly promising new class of serological markers are long non-coding RNAs. Long non-coding RNAs are a relatively recently discovered class of regulatory RNA molecules that play critical roles in many cellular and physiological processes. The potential role that long non-coding RNAs play with glioma pathogenic processes is not fully understood. In this literature review, we highlight the potential for long non-coding RNAs to be used as serum biomarkers in glioblastoma patients, including their potential to serve as non-invasive, easy to use, and rapid diagnostic or prognostic indicators.

Flow diverter stenting for intracranial aneurysms in the pediatric population: Two case reports and literature review.

The Pipeline Embolization Device (PED) is a flow-diverting intraluminal device that is approved for use in adults 18 years or older with internal carotid artery aneurysms. However, it can also be used off-label in pediatric patients with aneurysms that cannot be resolved with traditional endovascular treatments. Herein, we present two cases of flow diversion in the pediatric population with complete obliteration of the aneurysm and excellent outcomes. Flow diversion has been shown to be a safe endovascular option in treating complex aneurysms in children. Larger-sized, multicenter trials are encouraged to compare outcomes between flow diversion and other aneurysm treatment options given the rarity of pediatric aneurysms.

Radiological Biomarkers for Brain Metastases Prognosis: Quantitative Magnetic Resonance Imaging (MRI) Modalities As Non-invasive Biomarkers for the Effect of Radiotherapy.

Radiotherapy effect is achieved by its ability to cause DNA damage and induce apoptosis. In contrast, radiation can induce tumor cells' proliferation, invasiveness, and epithelial-mesenchymal transition (EMT). Besides developing radioresistance, this paradoxical effect of radiotherapy is considered a challenging problem in the field of radiotherapy. This highlights the importance of developing new modalities to diagnose radioresistance early to avoid any unnecessary exposure to radiation and differentiate between metastases recurrence versus post-radiation changes. Quantitative magnetic resonance imaging (MRI) techniques including diffusion-weighted imaging (DWI), dynamic susceptibility contrast (DSC), arterial spin labeling (ASL), and dynamic contrast-enhanced (DCE) represent potential biomarkers to diagnose metastases recurrence and radioresistance. In this review, we will focus on recent studies discussing the possibility of using DWI, DSC, ASL, and DCE to diagnose radioresistance and recurrence in patients with brain metastases.

Advances in Brain Metastases Diagnosis: Non-coding RNAs As Potential Biomarkers.

Brain metastasis is considered the most common brain tumor. They arise from different primary cancers. The most common primary tumors giving brain metastases include breast, colorectal, lung, melanoma, and renal cancer. Depending only on history, physical examination, and conventional imaging modalities makes brain tumors diagnosis difficult. Rapid and non-invasive promising modalities could diagnose and differentiate between different brain metastases without exposing the patients to unnecessary brain surgeries for biopsies. One of these promising modalities is non-coding RNAs (ncRNAs). NcRNAs can determine brain metastases' prognosis, chemoresistance, and radioresistance. It also helps us to understand the pathophysiology of brain metastases development. Additionally, ncRNAs may work as potential therapeutic targets for brain metastases treatment and prevention. Herein, we present deregulated ncRNAs in different brain metastases, including microRNAs and long non-coding RNAs (lncRNAs), such as gastric adenocarcinoma, colorectal, breast, melanoma, lung, and prostate cancer. Additionally, we focus on serum and cerebrospinal fluid (CSF) expression of these ncRNAs in patients with brain metastases compared to patients with primary tumors. Moreover, we discuss the role of ncRNAs in modulating the immune response in the brain microenvironment. More clinical studies are encouraged to assess the specificity and sensitivity of these ncRNAs.

Non-coding RNAs as Genetic Biomarkers for the Diagnosis, Prognosis, Radiosensitivity, and Histopathologic Grade of Meningioma.

Meningioma is considered the most common primary benign brain tumor. It originates from the arachnoid cells of the leptomeninges surrounding the brain. The mainstay treatment of meningiomas is microsurgical resection. Meningioma prognosis depends on tumor grade, location, and patient age. Recently, using non-coding RNA as a prognostic and diagnostic biomarker for many tumors became a trend. Herein, we demonstrate the importance of non-coding RNAs, including microRNAs and lncRNAs in meningioma and their potential role in meningioma's early diagnosis, prognosis, histological grade, and radiosensitivity. In this review, many microRNAs were found to be upregulated in radioresistant meningioma cells such as microRNA-221, microRNA-222, microRNA-4286, microRNA-4695-5p, microRNA-6732-5p, microRNA-6855-5p, microRNA-7977, microRNA-6765-3p, and microRNA-6787-5p. Moreover, there are many microRNAs downregulated in radioresistant meningioma cells such as microRNA-1275, microRNA-30c-1-3p, microRNA-4449, microRNA-4539, microRNA-4684-3p, microRNA-6129, and microRNA-6891-5p. Also, we highlight the possible use of non-coding RNAs as serum non-invasive biomarkers and their potential role as therapeutic targets to treat high-grade meningiomas. Recent studies show that microRNA-497, microRNA-195, microRNA-18a, microRNA-197, and microRNA-224 are downregulated in the serum of patients with meningiomas. Additionally, microRNA-106a-5p, microRNA-219-5p, microRNA-375, and microRNA-409-3p are found to be upregulated in the serum of patients with meningioma. We also found that there are many deregulated microRNAs in meningioma cells that can be used as potential biomarkers for meningioma diagnosis, prognosis, and histopathologic grade, such as microRNA-17-5p, microRNA-199a, microRNA-190a, microRNA-186-5p, microRNA155-5p, microRNA-22-3p, microRNA-24-3p, microRNA-26-5p, microRNA-27a-3p, microRNA-27b-3p, microRNA-96-5p, microRNA-146a-5p, microRNA-29c-3p, microRNA-219-5p, microRNA-335, microRNA-200a, microRNA-21, microRNA-107, microRNA-224, microRNA-195, microRNA-34a-3p, and microRNA-let-7d. Of interest, we found fewer studies discussing deregulated long non-coding RNAs (lncRNAs) in meningioma cells. LncRNAs work as competitive endogenous RNA (ceRNA) by binding to oncogenic or anti-oncogenic microRNAs. We found that lncRNA- NUP210, lncRNA-SPIRE2, lncRNA-SLC7A1, lncRNA-DMTN, lncRNA-LINC00702, and lncRNA-LINC00460 are upregulated in meningioma cells. In contrast, lncRNA-MALAT1 was found to be downregulated in meningioma cells.

Cisternostomy as a Surgical Treatment for Traumatic Brain Injury-Related Prolonged and Delayed Intracranial Pressure Elevation: A Case Report.

Traumatic brain injury (TBI) can be classified into primary, due to the effect of the initial trauma, or secondary, due to increased intracranial pressure (ICP). Increased ICP may cause brain herniation and also decreases cerebral blood perfusion leading to ischemia. Recently, a few studies showed that cisternostomy with decompressive craniectomy (DC) has better outcomes than DC alone in patients with TBI. This can be explained by the recent advances indicating that cisternal cerebrospinal fluid (CSF) communicates with cerebral interstitial fluid (IF) through Virchow-Robin spaces. Theoretically, opening cisterns to atmospheric pressure may induce IF drainage and subsequently decrease ICP. A 55-year-old man presented to the emergency department with subdural hematomas, hemorrhagic contusions, and subarachnoid hemorrhage after falling off a moving truck. ICP elevation was refractory despite increased sedation, initiation of paralysis with Cisatracurium, esophageal cooling, multiple doses of 23.4 % saline and mannitol, and DC. Lumbar drain (LD) placement was performed with beneficial results. Unfortunately, the LD stopped functioning multiple times and each time this occurred, he developed increased ventricular size with elevated ICP. The patient underwent cisternostomy and lamina terminalis fenestration. No further increased ICPs were observed after cisternostomy at a one-month follow-up. Cisternostomy is a potential surgical treatment for patients with TBI-related prolonged ICP elevation.

Pseudo-Allergies in the Emergency Department: A Common Misdiagnosis of Hypersensitivity Type 1 Allergic Reaction.

Type-1 hypersensitivity reaction represents an acute IgE-mediated reaction that can cause life-threatening conditions, such as anaphylactic shock, angioedema, and airway obstruction. Other reactions that can mimic type-1 hypersensitivity reactions include IgE-independent mast cell degranulation, bradykinin-mediated reactions, leukotrienes-mediated reactions, and pseudo-allergies. We use the term pseudo-allergy in this article for histamine-mediated reactions that are mast cell-independent. We did not discuss pseudo-allergic reactions that are not acute or life-threatening, such as celiac disease, Heiner's syndrome, eosinophilic esophagitis, and food protein-induced enterocolitis in our article because the emergency department is not the primary location to diagnose or treat these reactions. Herein, we present some allergic-like reactions that can be life-threatening, such as scombroid food poisoning (SFP), bradykinin-induced angioedema, IgE-independent angioedema, opioid-induced angioedema, and non-steroidal anti-inflammatory drug (NSAID)-induced hypersensitivity and angioedema. These reactions may have different treatments based on their mechanism of reaction. Histamine-mediated reactions, such as SFP, histamine-mediated angioedema, and mast cell degranulation induced by NSAIDs, and opioids can be treated with antihistamines, epinephrine, and corticosteroids. Bradykinin-induced angioedema, including hereditary angioedema and acquired angioedema, can be treated with fresh frozen plasma. Hereditary angioedema can be treated with many FDA-approved targeted medications, such as plasma-derived C1-INH, plasma kallikrein inhibitor (Ecallantide), and selective bradykinin-2 receptor antagonist (Icatibant). However, these targeted agents are not well-studied enough to be used for acquired angioedema. It is crucial for emergency medicine physicians to be familiar with and predict these reactions to prevent misdiagnosis, be prepared to treat these life-threatening conditions appropriately without delay and eliminate patients' exposure to any unnecessary investigations or treatments.

Cervical spine spondylodiscitis: Review of literature on current treatment strategies.

Infections of the spine are an ever-increasing health concern requiring an often complex and prolonged treatment that can lead to significant morbidity. Of particular interest is the cervical spine where there is an increase rate of post-infectious deformity, secondary neurological deficits and substantially higher rates of associated morbidity and mortality than the thoracic or lumbar spine. In this review, we explore the diagnosis and treatment of spondylodiscitis with particular focus on the cervical spine.

Cisternotomy and Liliequist's Membrane Fenestration as a Surgical Treatment for Idiopathic Intracranial Hypertension (Pseudotumor Cerebri): A Case Report.

Subarachnoid basal cistern opening (cisternotomy) is used during many microsurgical operations to relax the brain by removing or diverting cerebrospinal fluid (CSF). Recently, cisternotomy has been used in patients with traumatic brain injury to improve outcomes due to its ability to decrease intracranial pressure (ICP) and brain edema by diverting CSF. Theoretically, another condition that can benefit from cisternotomy is idiopathic intracranial hypertension (IIH) as it presents with manifestations of increased ICP, such as headache, vomiting, and papilledema. Here, we discuss the case of a 39-year-old woman with IIH who presented with headache, nausea, and papilledema in the setting of maximally tolerated medical management after five months of shunt removal due to infection. The patient did not want to proceed with the replacement of her shunt and therefore underwent a right eyebrow craniotomy for cisternotomy, lamina terminals fenestration, and Liliequist's membrane opening. Postoperatively, her symptoms improved completely. She was off acetazolamide altogether at the three-month follow-up and no longer had pseudotumor cerebri headaches. This case report demonstrates the use of cisternotomy to relieve the manifestations of increased ICP and its potential as a surgical option for patients with IIH.

Intraosseous Meningioma Along the Left Petrous Bone: A Rare Cause of Trigeminal Neuralgia.

Trigeminal neuralgia (TN) presents with symptoms of intense recurrent shock-like brief pain localized to specific areas of the face innervated by the fifth cranial nerve. The pathology of trigeminal neuralgia is attributed to the fifth cranial nerve compression or demyelination. Most cases of this diagnosis are not due to bony structures, making this case an uncommon presentation of trigeminal neuralgia. Herein, we present a case of trigeminal neuralgia due to an intraosseous meningioma that formed along the left petrous bone, resulting in trigeminal nerve compression. On head computed tomography (CT), osteomatous growths along the left petrous bone were noticed compressing the trigeminal nerve. After trigeminal nerve decompression and drilling out the protruding part of the petrous bone through middle cranial fossa craniotomy, the patient's symptoms were completely improved postoperatively and at the two-month follow-up. To our knowledge, there are only four reported cases of trigeminal neuralgia caused by petrous bone compression in the literature. We emphasize the significance of considering petrous bone lesions as a cause of trigeminal neuralgia.

Large Middle Cranial Fossa Schwannoma: A Rare Presentation of Vestibular Schwannoma.

Schwannomas are benign tumors composed of neoplastic Schwann cells and rarely occur in the central nervous system. Schwannomas account for approximately 8% of intracranial tumors and most commonly originate from cranial nerve VIII at the cerebellopontine angle in the posterior fossa. Herein, we report two cases of vestibular schwannomas extending in the middle fossa. The first case shows a 51-year-old male who presented with a history of mild headaches for one year associated with acute nausea, vomiting, and word-finding difficulties. Imaging revealed a large multicystic contrast-enhancing lesion in the left middle cranial fossa. The middle fossa lesion was resected with pathology indicating a schwannoma. The second case shows a 63-year-old woman who presented with seizures, right-sided hearing loss, and right-sided facial weakness. On MRI, she is found to have a large right middle fossa lesion originating from the right internal auditory canal and consistent with vestibular schwannoma with a 9 mm leftward midline shift. The histopathologic examination of the excised tumor indicated a schwannoma. Schwannomas most commonly occur in the posterior fossa when they present intracranially. However, in rare occurrences, they may present as middle fossa masses with significant intracranial compression.

Analyzing outcomes of neurosurgical operations performed before and during the COVID-19 pandemic in Egypt. A matched single-center cohort study.

BACKGROUND: Since the emergence of the first COVID-19 case in Wuhan, the virus affected several health care systems. Globally, the COVID-19 has a transforming effect on health care provision. Substantial evidence was clear that the global surgical services were impacted. The field of neurosurgery was primarily affected, and most elective surgeries were suspended. There are no current reports from Egypt that describe the mortality outcome of neurosurgical procedures in the context of the pandemic. METHODS: We performed that study at a large tertiary center in Egypt (Cairo University Hospital). It is a single-center matched cohort study. RESULTS: Our results examined about 346 patients earlier during the COVID-19 pandemic. About 46 (13.29%) were unmatched, so we excluded them from the final analysis of the data. About 300 patients' were matched to 304 patients' before the pandemic in 2019. The mortality outcome of neurosurgical interventions was higher during the pandemic. CONCLUSIONS: Amid the COVID-19 pandemic, the mortality outcome of neurosurgical procedures was higher than on regular days at our center. The anesthesia time was prolonged while the operation time was shortened. We strongly suggest further multicenter studies to assess the effect of COVID-19 on neurosurgical mortality and functional outcome.