Nocardial brain abscess mimicking lung cancer metastasis in immunocompetent patient with pulmonary nocardiasis: a case report.

Nocardia is a ubiquitous microorganism which can be the cause of local and disseminated infection in humans. Immunocompetent and immunocompromised patients both can be affected and Nocardia cyriacigeorgica was reported as a pathogen isolated in patients worldwide. In most cases, nocardiosis is present as pulmonary infection because inhalation is the primary way of bacterial exposure. Nocardial brain abscess occurs usually secondary to a septic focus elsewhere in the body. Considering the facts that the elderly population is growing, such as the number of immunocompromised patients together with high mortality rate in patients with nocardial infection of the central nervous system, we have to raise awareness of the possibility for this rare but potentially fatal condition. We present a case where nocardial abscesses of lung and brain were initially suspected as lung cancer with brain metastases. The patient was treated with a combination of surgical resection and antimicrobial therapy with good outcome.

Cranioorbital Pretemporal Skull Base Approach with Anterior Clinoidectomy for Removal of Large Left Clinoid Meningioma: "Unwrapping" Encircled Internal Carotid Artery and Decompressing Optic Nerve: 2-Dimensional Operative Video.

Clinoidal meningiomas are meningiomas arising from or in the vicinity of the anterior clinoid process.1 Despite advanced microsurgical techniques, clinoidal meningiomas remain challenging.2 Extradural anterior clinoidectomy with optical unroofing remains an important tool in skull base surgery, which provides a safe operative corridor, facilitating greater extent of resection and enhancing overall outcome, particularly visual function.2-13 A 66-year-old woman presented with history of visual disturbances. Magnetic resonance imaging revealed a dural-based tumor consistent with a large left clinoidal meningioma, with tumor wrapping (encircling) around the left trunk and internal carotid artery (ICA) bifurcation, elevating the left middle cerebral artery M1 segment, and invading the left optic canal. Left cranio-orbital craniotomy with pretemporal exposure was used (Video 1).1,9 A high-speed diamond drill with irrigation completed the extradural anterior clinoidectomy and optical canal unroofing. Use of a 1-mm Kerrison rongeur should be done with utmost care. The tumor was unwrapped via meticulous piecemeal removal. Final dissection and ICA unwrapping was done when the tumor was debulked enough that dissecting it off the artery was safe and under less tension. Due to its obscurity, final decompression of the left optic nerve with incision and opening of the falciform ligament was performed at the end of the procedure.10 Postoperative neuro-ophthalmologic examination showed a grossly unchanged left visual field with some visual acuity improvement. Resection of tumor encircling the ICA has been described previously;14 however, to the best of our knowledge, this is the first video describing removal of a tumor surrounding the ICA (perfomed by senior author K.I.A.), essentially "unwrapping" the left ICA trunk and its bifurcation. The patient consented to publication.

An integrative survival analysis and a systematic review of the cerebellopontine angle glioblastomas.

Glioblastomas presenting topographically at the cerebellopontine angle (CPA) are exceedingly rare. Given the specific anatomical considerations and their rarity, overall survival (OS) and management are not discussed in detail. The authors performed an integrative survival analysis of CPA glioblastomas. A literature search of PubMed, Scopus, and Web of Science databases was performed per PRISMA guidelines. Patient data including demographics, clinical features, neuroimaging, management, follow-up, and OS were extracted. The mean age was 39 ± 26.2 years. The mean OS was 8.9 months. Kaplan-Meier log-rank test and univariate Cox proportional-hazards model identified hydrocephalus (log-rank, p = 0.034; HR 0.34; 95% CI 0.12-0.94; p = 0.038), chemotherapy (log-rank, p < 0.005; HR 5.66; 95% CI 1.53-20.88; p = 0.009), and radiotherapy (log-rank, p < 0.0001; HR 12.01; 95% CI 3.44-41.89; p < 0.001) as factors influencing OS. Hydrocephalus (HR 3.57; 95% CI 1.07-11.1; p = 0.038) and no adjuvant radiotherapy (HR 0.12; 95% CI 0.02-0.59; p < 0.01) remained prognostic on multivariable analysis with fourfold and twofold higher risk for the time-related onset of death, respectively. This should be considered when assessing the risk-to-benefit ratio for patients undergoing surgery for CPA glioblastoma.

Anterior Transpetrosal-Transtentorial Approach for Removal of a Large Petrous Apex Meningioma: 2-Dimensional Operative Video.

Video 1 demonstrates the microsurgical resection of petrous apex meningioma. Even small lesions by general rules are regarded as large due to the delicate nature of anatomic localization. The intricate relationship between the tumor and vascular supply of the brainstem and interposition of cranial nerves makes them challenging lesions to resect.1 A 67-year-old female patient presented with a 6-month history of trigeminal neuralgia in the V2 and V3 branches. She underwent gross total resection of an extraaxial homogenously enhancing dural-based tumor in the right petroclival region, consistent with a large (3-4.5 cm) petrous apex meningioma, the least frequently reported subtype of petroclival meningiomas.2,3 Skull base approaches for surgical resection of these tumors include high-speed drilling of petrous bone to create a corridor that facilitates access to the lesion.1 Preserved hearing with suprameatal extension of the infratentorial component and absence of a tumor laterally and inferiorly to the internal auditory canal provided the rationale for selecting a subtemporal approach combined with anterior petrosectomy.1,4,5 Identification of anatomic landmarks of the Kawase triangle is the key first step for determining the bony removal corridor, outlined by the greater superficial petrosal nerve, the arcuate eminence, and the petrous ridge.1,6 An important step in surgical removal is the devascularization of feeding arteries arising from the meningohypophyseal trunk.7,8 Subsequent piecemeal removal and circumferential detachment while making sure to preserve major vascular and nerve elements is crucial for successful removal. The patient consented to the procedure. The postoperative course was uneventful. The patient's trigeminal neuralgia completely regressed with no new neurologic deficit.

Case Report: Atypical Solitary Brain Metastasis: The Role of MR Spectroscopy In Differential Diagnosis.

Background: Metastatic brain tumors are typically located at the cerebral hemispheres or the cerebellum and most frequently originate from primary breast or lung tumors. Metastatic lesions are usually associated with blood-brain barrier disruption, solid or ring-like contrast enhancement, and perilesional vasogenic edema on brain imaging. Even in cases where metastases are predominantly cystic, enhancement of the minor solid component can be detected. In contrast, non-enhancing secondary brain tumors were only reported in a patient after antiangiogenic treatment with bevacizumab. Case report: We report a case of a 54-year-old male who presented with left-sided weakness and multiple seizures. Brain magnetic resonance imaging revealed a T2-weighted heterogeneous solid tumor in the right frontoparietal parasagittal region, with no apparent enhancement on T1-weighted post-contrast images and no evident perilesional edema. Further MRS analysis revealed markedly increased choline and lipid peaks. The patient underwent craniotomy for tumor removal. Histopathology revealed findings consistent with metastatic non-microcellular neuroendocrine lung cancer. positron emission tomography/computed tomography (PET/CT) revealed a stellate lesion within the right upper lung lobe, compatible with primary lung cancer. Conclusion: Non-enhancing brain metastatic tumors are rarely reported in the literature, usually following antiangiogenic treatment. Here, we report the first ever case of a non-enhancing metastatic brain tumor with no prior history of antiangiogenic treatment, with particular emphasis on the importance of MRS analysis in atypical brain lesions.

Venous thromboembolic and hemorrhagic events after meningioma surgery: A single-center retrospective cohort study of risk factors.

Microsurgical resection of meningiomas in a majority of cases leads to a favorable outcome. Therefore, severe postoperative adverse events are less acceptable. The main purpose of this study was to investigate the incidence of symptomatic venous thromboembolism (VTE) and hemorrhagic complications in patients after operative treatment of intracranial meningiomas and to identify the risk factors in this patient subgroup. Of 106 patients undergoing elective craniotomy for meningioma overall incidence of symptomatic VTE was noted in 5.7% (six patients). For the risk-factor analysis older age (57.20 ± 11.60 vs. 71.00 ± 0.90 years, p < 0.001), higher body mass index (27.60 ± 4.80 vs. 33.16 ± 0.60 kg/m2, p < 0.001), WHO grade II (3.00% vs. 33.33%, p = 0.02), lower intraoperative blood loss (466.00 ± 383.70 vs. 216.70 ± 68.30 mL, p < 0.001), bedridden status and neurologic deficit (0.00% vs. 33.33%, p = 0.003 and 38.00% vs. 100.00%, p = 0.004) were associated with greater VTE risk. No risk factors for hemorrhagic complications were identified on univariate analysis. In conclusion, the incidence of VTE in meningioma patients is not negligible. Identified risk factors should be taken into account in the decision-making process for chemoprophylaxis when the risk of bleeding decreases.

Metabolomics as a potential tool for monitoring patients with aneurysmal subarachnoid hemorrhage.

Metabolomics has evolved into a particularly useful tool to study interactions between metabolites and serves as an aid in unraveling the complexity of entire metabolomes. Nonetheless, it is increasingly viewed as a methodology with practical applications in the clinical setting, where identifying and quantifying biomarkers of interest could prove useful for diagnostics. Starting from a concise overview of the most prominent analytical techniques employed in metabolomics, herein we present a review of its application in studies of brain metabolism and cerebrovascular diseases, paying most attention to its uses in researching aneurysmal subarachnoid hemorrhage. Both animal models and human studies are considered, and metabolites identified as potential biomarkers are highlighted.

Primary Intraparenchymal Meningiomas: A Case Report and a Systematic Review.

BACKGROUND: Primary intraparenchymal meningiomas are exceedingly rare and often challenging to diagnose, given their misleading radiologic features. It is hypothesized that they arise from the cap cells of the pia mater that enter the brain via penetrating blood vessels during brain development. We systematically reviewed and analyzed previously reported features of primary intraparenchymal meningiomas in terms of radiography, presenting symptoms, and histopathology. METHODS: A literature search of the Web of Science and PubMed databases and crossed references was performed in March 2021, per PRISMA guidelines, with no restrictions regarding publication date. Data regarding demographic features, clinical, radiographic, and histopathologic characteristics were extracted. RESULTS: A total of 52 patients (including the reported case) were included in this review. The mean age was 21.1 years (range, 0.3-66 years) with a male/female ratio of 1.9:1. The most common localizations of intraparenchymal meningiomas were in the frontal (30.8%) and temporal (21.2%) lobes. Cyst formation was more readily observed and was noted in 51.4% of patients. Histopathology showed a higher incidence of World Health Organization grade II (14/52, 26.9%) and World Health Organization grade III (7/52, 13.5%) of primary intraparenchymal meningiomas. CONCLUSIONS: We present a comprehensive analysis of every reported primary intraparenchymal meningioma. Because of their rarity and capacity to mimic other more common intra-axial tumors, they represent a diagnostic challenge. This systematic review highlights the importance of paying attention to atypical intra-axial lesions, with a particular reflection on the discrepancy between clinical characteristics and imaging features.