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In the management of aneurysmal subarachnoid hemorrhage (aSAH), aneurysm treatment as early as feasible is mandatory to minimize the risk of a rebleed and may thus improve outcome. We assessed the different time intervals from the first symptoms of aSAH to start of aneurysm treatment in an effort to identify which factors contribute mostly to a delay in time to treatment. In 278 aSAH patients, time intervals between the different steps from initial hemorrhage to aneurysm treatment were retrospectively reviewed, and delaying factors were determined. Half of the patients presented to a hospital within 115 min (IQR 60-431). The median (IQR) interval from hemorrhage to diagnosis was 169 min (96-513), and from diagnosis to treatment 1,057 min (416-1,428), or 17.6 h. Aneurysm treatment started within 24 h in 76 % of treated patients. Independent factors predicting delay to treatment were primary presentation at a referring hospital and admission to the treatment center later in the day. Delay in treatment was not independently related to poor outcome. The interval to aneurysm treatment might be improved upon by immediate and direct transport to the treatment center combined with optimization of in-hospital logistics, following the 'time-is-brain' concept so successfully adopted in the treatment of ischemic stroke. [ABSTRACT FROM AUTHOR]

Background: Convection-enhanced delivery (CED) of adenoviruses offers the potential of widespread virus distribution in the brain. In CED, the volume of distribution (Vd) should be related to the volume of infusion (Vi) and not to dose, but when using adenoviruses contrasting results have been reported. As the characteristics of the infused tissue can affect convective delivery, this study was performed to determine the effects of the gray and white matter on CED of adenoviruses and similar sized super paramagnetic iron oxide nanoparticles (SPIO). Methodology/Principal Findings: We convected AdGFP, an adenovirus vector expressing Green Fluorescent Protein, a virus sized SPIO or trypan blue in the gray and white matter of the striatum and external capsule of Wistar rats and towards orthotopic infiltrative brain tumors. The resulting Vds were compared to Vi and transgene expression to SPIO distribution. Results show that in the striatum Vd is not determined by the Vi but by the infused virus dose, suggesting diffusion, active transport or receptor saturation rather than convection. Distribution of virus and SPIO in the white matter is partly volume dependent, which is probably caused by preferential fluid pathways from the external capsule to the surrounding gray matter, as demonstrated by co-infusing trypan blue. Distant tumors were reached using the white matter tracts but tumor penetration was limited. Conclusions/Significance: CED of adenoviruses in the rat brain and towards infiltrative tumors is feasible when regional anatomical differences are taken into account while SPIO infusion could be considered to validate proper catheter positioning and predict adenoviral distribution. [ABSTRACT FROM AUTHOR]

Background: The risk of rebleeding after aneurysmal subarachnoid hemorrhage (aSAH) is the highest during the initial hours after rupture. Emergency aneurysm treatment may decrease this risk, but is a logistic challenge and economic burden. We aimed to investigate whether aneurysm treatment <6 h after rupture is associated with a decreased risk of poor functional outcome compared to aneurysm treatment 6-24 h after rupture., Methods: We used data of patients included in the ULTRA trial (NCT02684812). All patients in ULTRA were admitted within 24 h after aneurysm rupture. For the current study, we excluded patients in whom the aneurysm was not treated <24 h after rupture. We calculated crude and adjusted risk ratios (aRR) with 95% confidence intervals using Poisson regression analyses for poor functional outcome (death or dependency, assessed by the modified Rankin Scale) after aneurysm treatment <6 h versus 6-24 h after rupture. Adjustments were made for age, sex, clinical condition on admission (WFNS scale), amount of extravasated blood (Fisher score), aneurysm location, tranexamic acid treatment, and aneurysm treatment modality., Results: We included 497 patients. Poor outcome occurred in 63/110 (57%) patients treated within 6 h compared to 145/387 (37%) patients treated 6-24 h after rupture (crude RR: 1.53, 95% CI: 1.24-1.88; adjusted RR: 1.36, 95% CI: 1.11-1.66)., Conclusion: Aneurysm treatment <6 h is not associated with better functional outcome than aneurysm treatment 6-24 h after rupture. Our results do not support a strategy aiming to treat every patient with a ruptured aneurysm <6 h after rupture.

OBJECTIVE Pediatric high-grade gliomas (pHGGs) including diffuse intrinsic pontine gliomas (DIPGs) are primary brain tumors with high mortality and morbidity. Because of their poor brain penetrance, systemic chemotherapy regimens have failed to deliver satisfactory results; however, convection-enhanced delivery (CED) may be an alternative mode of drug delivery. Anthracyclines are potent chemotherapeutics that have been successfully delivered via CED in preclinical supratentorial glioma models. This study aims to assess the potency of anthracyclines against DIPG and pHGG cell lines in vitro and to evaluate the efficacy of CED with anthracyclines in orthotopic pontine and thalamic tumor models. METHODS The sensitivity of primary pHGG cell lines to a range of anthracyclines was tested in vitro. Preclinical CED of free doxorubicin and pegylated liposomal doxorubicin (PLD) to the brainstem and thalamus of naïve nude mice was performed. The maximum tolerated dose (MTD) was determined based on the observation of clinical symptoms, and brains were analyzed after H & E staining. Efficacy of the MTD was tested in adult glioma E98-FM-DIPG and E98-FM-thalamus models and in the HSJD-DIPG-007-Fluc primary DIPG model. RESULTS Both pHGG and DIPG cells were sensitive to anthracyclines in vitro. Doxorubicin was selected for further preclinical evaluation. Convection-enhanced delivery of the MTD of free doxorubicin and PLD in the pons was 0.02 mg/ml, and the dose tolerated in the thalamus was 10 times higher (0.2 mg/ml). Free doxorubicin or PLD via CED was ineffective against E98-FM-DIPG or HSJD-DIPG-007-Fluc in the brainstem; however, when applied in the thalamus, 0.2 mg/ml of PLD slowed down tumor growth and increased survival in a subset of animals with small tumors. CONCLUSIONS Local delivery of doxorubicin to the brainstem causes severe toxicity, even at doxorubicin concentrations that are safe in the thalamus. As a consequence, the authors could not establish a therapeutic window for treating orthotopic brainstem tumors in mice. For tumors in the thalamus, therapeutic concentrations to slow down tumor growth could be reached. These data suggest that anatomical location determines the severity of toxicity after local delivery of therapeutic agents and that caution should be used when translating data from supratentorial CED studies to treat infratentorial tumors.