Molecular Sequence of Events and Signaling Pathways in Cerebral Metastases

Brain metastases are the leading cause of morbidity and mortality among cancer patients, and are reported to occur in about 40% of cancer patients with metastatic disease in the United States of America. Primary tumor cells appear to detach from the parent tumor site, migrate, survive and pass through the blood brain barrier in order to establish cerebral metastases. This complex process involves distinct molecular and genetic mechanisms that mediate metastasis from these primary organs to the brain. Furthermore, an interaction between the invading cells and cerebral milieu is shown to promote this process as well. Here, we review the mechanisms by which primary cancer cells metastasize to the brain via a mechanism called epithelial-to-mesenchymal transition, as well as the involvement of certain microRNA and genetic aberrations implicated in cerebral metastases from the lung, breast, skin, kidney and colon. While the mechanisms governing the development of brain metastases remain a major hindrance in treatment, understanding and identification of the aforementioned molecular pathways may allow for improved management and discovery of novel therapeutic targets

Isolated Intraventricular Hemorrhage Associated with Cerebral Vasospasm and Delayed Cerebral Ischemia following Arteriovenous Malformation Rupture

Background: Although it is well characterized in aneurysmal subarachnoid hemorrhage, vasospasm is exceedingly rare following cerebral arteriovenous malformation (AVM) rupture. Subsequently, this complication is poorly characterized with regard to delayed cerebral ischemia (DCI). We review cases of ruptured AVM to assess the frequency and severity of vasospasm on cerebral angiography, and DCI. Summary: We reviewed our institutional database of acute intracranial hemorrhages between 2005 and 2014. We identified patients with cerebral AVM rupture and evidence of vasospasm, which was confirmed with digital subtraction angiography (DSA). Cerebral angiograms were evaluated by 2 blinded neurointerventionalists for vasospasm. Statistical analyses were conducted on the angiographic results and variables of interest to determine predictors and associations of vasospasm and DCI. Thirty-six patients with acute intracranial hemorrhage due to ruptured cerebral AVM subsequently underwent cerebral angiography. The interrater reliability for vasospasm was 0.81. The incidence of vasospasm was 13.9% and the incidence of subsequent DCI was 11.1%. A significant relationship existed between isolated intraventricular hemorrhage and vasospasm (p = 0.001) and subsequent DCI (p = 0.006). Radiographic vasospasm was associated with DCI in 80% of the patients (p\u3c0.0001). No statistical significance existed between subarachnoid hemorrhage and the development of vasospasm or DCI (p = 1.000 and p = 0.626, respectively). All differences were significant at a 99% level of significance. Key Message: In cases of ruptured AVM, isolated intraventricular hemorrhage appears to be an independent risk factor for vasospasm and DCI. Vasospasm must be considered during late neurological deterioration following AVM hemorrhage, especially in the setting of isolated intraventricular hemorrhage

Incidence, Characteristics and Outcomes of Large Vessel Stroke in COVID-19 Cohort: An International Multicenter Study.

BACKGROUND: While there are reports of acute ischemic stroke (AIS) in coronavirus disease 2019 (COVID-19) patients, the overall incidence of AIS and clinical characteristics of large vessel occlusion (LVO) remain unclear. OBJECTIVE: To attempt to establish incidence of AIS in COVID-19 patients in an international cohort. METHODS: A cross-sectional retrospective, multicenter study of consecutive patients admitted with AIS and COVID-19 was undertaken from March 1 to May 1, 2020 at 12 stroke centers from 4 countries. Out of those 12 centers, 9 centers admitted all types of strokes and data from those were used to calculate the incidence rate of AIS. Three centers exclusively transferred LVO stroke (LVOs) patients and were excluded only for the purposes of calculating the incidence of AIS. Detailed data were collected on consecutive LVOs in hospitalized patients who underwent mechanical thrombectomy (MT) across all 12 centers. RESULTS: Out of 6698 COVID-19 patients admitted to 9 stroke centers, the incidence of stroke was found to be 1.3% (interquartile range [IQR] 0.75%-1.7%). The median age of LVOs patients was 51 yr (IQR 50-75 yr), and in the US centers, African Americans comprised 28% of patients. Out of 66 LVOs, 10 patients (16%) were less than 50 yr of age. Among the LVOs eligible for MT, the average time from symptom onset to presentation was 558 min (IQR 82-695 min). A total of 21 (50%) patients were either discharged to home or discharged to acute rehabilitation facilities. CONCLUSION: LVO was predominant in patients with AIS and COVID-19 across 2 continents, occurring at a significantly younger age and affecting African Americans disproportionately in the USA

Retrosigmoid Craniectomy for Resection of Epidermoid causing Trigeminal Neuralgia

The differential diagnosis for trigeminal neuralgia like-symptoms includes cerebellopontine angle lesions causing regional mass effect upon the trigeminal nerve ( Fig. 1 ). Here we present an operative video manuscript of a patient experiencing trigeminal neuralgia, secondary to an epidermoid cyst, in which a retrosigmoid craniectomy was performed to resect the epidermoid and decompress the trigeminal nerve ( Fig. 2 ). This video highlights the operative nuances to achieving a successful surgery, including appropriate patient positioning, dural exposure to the transverse-sigmoid sinus junction, arachnoid dissection, and decompression of cranial nerves. A gross total resection was achieved; the patient reported immediate relief of facial pain postoperatively and has been pain free at the ten month follow-up. The link to the video can be found at: https://youtu.be/Ja2eE0uGk4E

Pipeline Embolization of Ruptured, Previously Coiled Cerebral Aneurysms: Case Series and Considerations for Management

PURPOSE: Aneurysmal recurrence represents a significant drawback of endovascular coiling, particularly in aneurysms that have previously ruptured. Given the high recurrence rate of coiled aneurysms and particularly the risk of posttreatment rupture in previously ruptured aneurysms that have been treated by coiling, the question of how best to treat ruptured aneurysms that recur postcoiling remains. MATERIALS AND METHODS: We conducted a retrospective analysis of twenty patients who underwent pipeline embolization of previously ruptured, coiled cerebral aneurysms. RESULTS: Pipeline embolization device (PED) treatment resulted in complete aneurysmal occlusion in 10 patients (62.5%) at first angiographic follow-up, and 11 patients (68.75%) at last follow-up. No PED-related complications were encountered and there were no peri-procedural or postprocedural hemorrhages, or symptomatic ischemic events following flow diversion. CONCLUSIONS: PED as a second-line treatment is a safe and effective modality for achieving aneurysmal occlusion in recurrent, previously ruptured, primarily coiled aneurysms. Additionally, a staged coil-to-PED approach may be considered for the management of acutely ruptured aneurysms to achieve aneurysmal obliteration in an effort to mitigate recurrence, and reduce the amount of postprocedural studies