Search

Physiologically relevant intracranial aneurysm (IA) models are crucially required to facilitate testing treatment options for IA. Herein, we report the development of a new in vitro tissue-engineered platform, which recapitulates the microenvironment, structure, and cellular complexity of native human IA. A new modified liquid-assisted injection molding technique was developed to fabricate a three-dimensional hollow IA model with clinically relevant IA dimensions within a mechanically tuned Gelatin Methacryloyl (GelMA) hydrogel. An endothelium lining was created inside the IA model by culturing human umbilical vein endothelial cells over pre-cultured human brain vascular smooth muscle cells. These cellularized IA models were subjected to medium perfusion at flow rates between 6.3 and 15.75 mL/min for inducing biomimetic vessel wall shear stress (10–25 dyn/cm2) to the cells for ten days. Both cell types maintained their secretome profiles and showed more than 96% viability, demonstrating the biocompatibility of the hydrogel during perfusion cell culture at such flow rates. Based on the characterized viscoelastic properties of the GelMA hydrogel and with the aid of a fluid-structure interaction model, the capability of the IA model in predicting the response of the IA to different fluid flow profiles was mathematically shown. With physiologically relevant behavior, our developed in vitro human IA model could allow researchers to better understand the pathophysiology and treatment of IA. A three-dimensional intracranial aneurysm (IA) tissue model recapitulating the microenvironment, structure, and cellular complexity of native human IA was developed. • An endothelium lining was created inside the IA model over pre-cultured human brain vascular smooth muscle cells over at least 10-day successful culture. • The cells maintained their secretome profiles, demonstrating the biocompatibility of hydrogel during a long-term perfusion cell culture. • The IA model showed its capability in predicting the response of IA to different fluid flow profiles. • The cells in the vessel region behaved differently from cells in the aneurysm region due to alteration in hemodynamic shear stress. • The IA model could allow researchers to better understand the pathophysiology and treatment options of IA. [Display omitted] [ABSTRACT FROM AUTHOR]

Objective: Imaging after blunt cervical trauma is being used increasingly to screen patients for injury of the vertebral artery (VA). There are no guidelines for imaging of the VA for nonpenetrating cervical trauma. The purpose of this study was to determine the effect of VA injury on clinical outcome after blunt cervical trauma. Methods: Sixty-six patients who underwent computed tomographic angiography (CTA) and magnetic resonance angiography (MRA) after blunt cervical trauma were reviewed. Medical records were reviewed for clinical status, including the presence of a neurologic deficit or pain related to spine or vascular injury. Any suggested brain injury was evaluated with diffusion-weighted MR imaging. Both clinical and radiographic data were analyzed to determine the incidence of VA abnormalities and their association with clinical outcome. Results: VA abnormalities were present in 19.7% of cases. Two patients had symptomatic brain sequelae from VA injury. There was no significant association between VA abnormalities and the presence of symptoms and/or cervical spine fractures at presentation. The presence of a fracture and neurologic symptoms at presentation predicted a significantly worse outcome at a mean follow-up of 5 months. However, the presence of VA abnormalities did not predict a worse clinical outcome. Conclusions: The clinical outcome of patients with blunt cervical trauma was not associated with the presence of VA abnormalities. Given the rare but potentially devastating consequences of a VA injury, however, screening may still be worthwhile. [Copyright &y& Elsevier]

Since hypertension and/or hyperglycemia are risk factors for stroke, we examined whether the putative neuroprotectant, nicotinamide (NAm), could protect spontaneously hypertensive rats (SHR) or diabetic Fischer 344 rats against focal cerebral ischemia using a model of permanent middle cerebral artery occlusion (MCAo). Intravenous NAm given 2 h after MCAo significantly reduced the infarct volume of SHR (750 mg/kg, 31%, P<0.01) and diabetic (500 mg/kg, 56%, P<0.01) as well as non-diabetic (500 mg/kg, 73%, P<0.01) Fischer 344 rats when compared with saline-injected controls. Thus delayed treatment with NAm protected hypertensive and hyperglycemic rats against a robust model of stroke. [Copyright &y& Elsevier]

Objective To present a case of a cavernous malformation presenting with a subdural hematoma. Methods A 27-year-old woman was admitted with progressively worsening headache, vomiting, weakness, and word-finding difficulties 1 week after she was discharged from an outside hospital, where she was managed conservatively for a presumed traumatic subdural hematoma. Computed tomography revealed an enlarging subacute left hemispheric subdural hematoma for which she underwent drill craniostomy. Postprocedural magnetic resonance imaging showed a posterior left temporal lobe mass consistent with a cavernous malformation juxtaposed with the subdural hematoma. Craniotomy for resection of the lesion was performed. She had an uncomplicated postoperative course and experienced a good recovery. Results The signs and symptoms, diagnostic imaging, and intraoperative findings suggest that the subdural hematoma was caused by extralesional hemorrhage of the cavernous malformation, which is a rare finding associated with these malformations. Conclusions The clinical course, radiologic, and intraoperative findings suggest that the subdural hemorrhage was caused by extralesional hemorrhage of the cavernous malformation. [ABSTRACT FROM AUTHOR]

Purpose To explore phase contrast (PC) magnetic resonance imaging of aneurysms and arteriovenous malformations (AVM). PC imaging obtains a vector field of the velocity and can yield additional hemodynamic information, including: volume flow rate (VFR) and intravascular pressure. We expect to find lower VFR distal to aneurysms and higher VFR in vessels of the AVM. Materials and Methods Five cerebral aneurysm and three AVM patients were imaged with PC techniques and compared to VFR of a healthy cohort. VFR was calculated in vessel segments in each patient and compared statistically to the healthy cohort by computing the z -score. Intravascular pressure was calculated in the aneurysms and in the nidus of each AVM. Results We found that patients with aneurysm had z < −0.48 in vessels distal to the aneurysm (reduced flow), while AVM patients had z > 6 in some vessels supplying and draining the nidus (increased flow). Pressures in aneurysms were highly variable between subjects and location, while in the nidus of the AVM patients; pressure trended higher in larger AVMs. Conclusion The study findings confirm the expectation of lower distal flow in aneurysm and higher arterial and venous flow in AVM patients. [ABSTRACT FROM AUTHOR]

One in five patients undergoing endovascular coiling (the current standard of care for treating intracranial aneurysms) experience a recurrence of the aneurysm as a result of improper healing. Recurrence remains the only major drawback of the coiling treatment and has been the focus of many studies over the last two decades. Cell therapy, a novel treatment modality in which therapeutic cells are introduced to the site of the injury to promote tissue regeneration, has opened up new possibilities for treating aneurysms. The healing response that ensues aneurysm embolization includes several cellular processes that can be targeted with cell therapy to prevent the aneurysm from recurring. Ten preclinical studies involving cell therapy to treat aneurysms were published between 1999 and 2014. In this review, we summarize the results of these studies and discuss advances, shortcomings, and the future of cell therapy for intracranial aneurysms. [ABSTRACT FROM AUTHOR]

The Barrow Neurological Institute (BNI), founded in 1961, is in partnership with St. Joseph''s Hospital and Medical Center and part of the Catholic Healthcare West system. The BNI is a relative newcomer to academic neuroscience. However, since its inception it has grown to become an international destination for neurologic disease. This article describes the history of the institute as it has grown over the years in its commitment to excellence in patient care, education, and research. [Copyright &y& Elsevier]

Creating aneurysm sizes in animal models that resemble human aneurysms is essential to study and test neuroendovascular devices. The commonly used rabbit surgical elastase model, however, produces saccular aneurysms that are smaller than those typically treated in humans. The goal of this study was to determine whether an increased vessel stump length and the addition of calcium chloride to the incubation solution has an effect on the resulting aneurysm size. Using a modified aneurysm creation method, 32 female New Zealand White rabbits underwent aneurysm creation procedures. Subjects were equally allocated into 4 different groups based on vessel stump length (2 cm controls vs. 3 cm) and incubation solution (elastase alone controls vs. a 1:1 mixture of elastase and calcium chloride). At 4 weeks, all animals underwent angiography to determine the resulting aneurysm size by a neurointerventionalist who was blinded to treatment group. An increase in stump length from 2 cm to 3 cm resulted in a significant increase in the height of aneurysm (P < 0.05). Compared with control animals, the combination of a 3-cm stump length and the addition of calcium chloride to the incubation solution resulted in a significant increase in aneurysm height, width, and volume (P < 0.05). Creating larger aneurysms is necessary for the rabbit model to be more clinically relevant. Our study demonstrated that the utilization of a 3-cm vessel stump as well as both calcium chloride and elastase in the incubation solution results in aneurysm sizes that more closely resemble the population of aneurysms treated in humans. [ABSTRACT FROM AUTHOR]

Aneurysm recurrence after Pipeline Embolization Device (PED) placement can be caused by oversizing of the stent as well as poor wall apposition, both of which can lead to elongation. The objective of this study was to assess whether a novel parameter for measuring device elongation based on two-dimensional imaging could be predictive for persistent aneurysm filling after treatment with the PED. A retrospective cohort analysis was initially completed on 41 aneurysms from institution A, examining demographic, aneurysmal, and device measurements. Device measurements, including the ratio of the measured length to the nominal length (ML/NL) of the PED, were taken by reviewers blinded to the primary end point, which was aneurysm occlusion status on 6 month catheter angiogram. Findings were then externally validated against 30 aneurysms (supraclinoid only) from institution B. Data from institution A showed 61% complete aneurysm occlusion at 6 months, and were lower for aneurysms in the supraclinoid region. For supraclinoid aneurysms alone, combined data from both institutions showed higher rates of nonocclusion with aneurysm neck size >4 mm (P = 0.008) and a trend toward significance in aneurysms with a branch vessel (P = 0.051). The mean ML/NL ratio was significantly larger in the nonoccluded group compared with the occluded group at both institution A (ratio, 1.37 versus 1.10; P < 0.001) and institution B (ratio, 1.36 vs. 1.11; P = 0.002). Our data suggest that a novel parameter based on two-dimensional angiography may serve as a rapid technique to measure device elongation and predict occlusion of supraclinoid aneurysms after PED placement. [ABSTRACT FROM AUTHOR]

Therapeutic hypothermia (TH) offers cerebral protection following ischemic stroke and may improve outcomes in conjunction with decompressive hemicraniectomy (DHC). We aimed to assess the effectiveness of TH in patients with malignant ischemic stroke and DHC. We performed a meta-analysis in patients with malignant ischemic stroke undergoing DHC comparing TH versus normothermia in studies published up to August 2019. Included studies had ≥10 adults with acute ischemic stroke. Primary outcome was functional independence, and secondary outcomes included complications. Effect size was pooled and described by relative risk (RR) ratios and 95% confidence intervals (CIs). Five studies (n = 269 patients; n = 130 TH, n = 139 controls) were included, 4 of which were prospective (n = 2 randomized controlled trials). Median achieved body temperature of TH was 33.6°C (range 33°C−35°C). Median modified Rankin Scale at the study completion was similar between TH and controls (RR 1.08, 95% CI 0.56–2.07, P = 0.8). Three studies reported individual patient modified Rankin Scale outcomes demonstrated a shift toward worse outcomes with TH (unadjusted common odds ratio 1.74; 95% CI 1.05–2.88, P = 0.01). Overall complications were similar between groups (RR 1.20, 95% CI 0.70–2.05, random effects P = 0.5). A suggestion of higher mortality was seen in TH (RR 1.50, 95% CI 0.97–2.32, P = 0.07). Clinical and functional outcomes were not overall different between patients undergoing systemic TH and controls following DHC despite the shift toward worse outcomes with TH observed in some studies. [ABSTRACT FROM AUTHOR]

Background Orbital lymphaticovenous malformations (LVMs) are congenital vascular lesions that are typically infiltrative in nature. There have been reports of orbital LVMs extending intracranially through orbital fissures, but there have been no reports of intradural extension. Case Description We report the first case of orbital LVM extending intradurally through a bony defect in the medial orbital roof. A modified orbitozygomatic approach was used to successfully obliterate this lesion. Neurosurgical and ophthalmologic collaboration was used in the surgical management of this case. Conclusions This case highlights the importance of an interdisciplinary approach when managing infiltrative orbital LVMs, as both ophthalmologic and neurosurgical expertise were critical in the success of the surgery. [ABSTRACT FROM AUTHOR]