Stroke; a journal of cerebral circulation 2013 Dec 3
Authors: Mikati AG, Tan H, Shenkar R, Li L, Zhang L, Guo X, Larsson HB, Shi C, Liu T, Wang Y, Shah A, Edelman RR, Christoforidis G, Awad I,
Hyperpermeability and iron deposition are 2 central pathophysiological phenomena in human cerebral cavernous malformation (CCM) disease. Here, we used 2 novel MRI techniques to establish a relationship between these phenomena.
Subjects with CCM disease (4 sporadic and 17 familial) underwent MRI imaging using the dynamic contrast-enhanced quantitative perfusion and quantitative susceptibility mapping techniques that measure hemodynamic factors of vessel leak and iron deposition, respectively, previously demonstrated in CCM disease. Regions of interest encompassing the CCM lesions were analyzed using these techniques.
Susceptibility measured by quantitative susceptibility mapping was positively correlated with permeability of lesions measured using dynamic contrast-enhanced quantitative perfusion (r=0.49; P≤0.0001). The correlation was not affected by factors, including lesion volume, contrast agent, and the use of statin medication. Susceptibility was correlated with lesional blood volume (r=0.4; P=0.0001) but not with lesional blood flow.
The correlation between quantitative susceptibility mapping and dynamic contrast-enhanced quantitative perfusion suggests that the phenomena of permeability and iron deposition are related in CCM; hence, more leaky lesions also manifest a more cumulative iron burden. These techniques might be used as biomarkers to monitor the course of this disease and the effect of therapy.
PMID: 24302484 [PubMed - as supplied by publisher]
International journal of stroke : official journal of the International Stroke Society 2013 Aug 28
Authors: Ziai WC, Tuhrim S, Lane K, McBee N, Lees K, Dawson J, Butcher K, Vespa P, Wright DW, Keyl PM, Mendelow AD, Kase C, Wijman C, Lapointe M, John S, Thompson R, Thompson C, Mayo S, Reilly P, Janis S, Awad I, Hanley DF, CLEAR III Investigators,
In adults, intraventricular thrombolytic therapy with recombinant tissue plasminogen activator (rtPA) facilitates resolution of intraventricular haemorrhage (IVH), reduces intracranial pressure, decreases duration of cerebrospinal fluid diversion, and may ameliorate direct neural injury. We hypothesize that patients with small parenchymal haematoma volumes (<30 cc) and relatively large IVH causing acute obstructive hydrocephalus would have improved clinical outcomes when given injections of low-dose rtPA to accelerate lysis and evacuation of IVH compared with placebo.
The Clot Lysis Evaluation of Accelerated Resolution of Intraventricular Hemorrhage III trial is an investigator-initiated, phase III, randomized, multicenter, double-blind, placebo-controlled study comparing the use of external ventricular drainage (EVD) combined with intraventricular injection of rtPA to EVD plus intraventricular injection of normal saline (placebo) for the treatment of IVH. Patients with known symptom onset within 24 h of the computed tomography scan confirmed IVH and third or fourth ventricle obstruction, with or without supratentorial intracerebral haemorrhage volume <30 cc, who require EVD are screened with a computed tomography scan at least six hours after EVD placement and, if necessary, at consecutive 12-h intervals until stabilization of any intracranial bleeding has been established. Patients who meet clinical and imaging criteria (no ongoing coagulopathy and no suspicion of aneurysm, arteriovenous malformation, or any other vascular anomaly) will be randomized to either intraventricular rtPA or placebo.
The primary outcome measure is dichotomized modified Rankin Scale 0-3 vs. 4-6 at 180 days. Clinical secondary outcomes include additional modified Rankin Scale dichotomizations at 180 days (0-4 vs. 5-6), ordinal modified Rankin Scale (0-6), mortality and safety events at 30 days, mortality at 180 days, functional status measures, type and intensity of intensive care unit management, rate and extent of ventricular blood clot removal, and quality of life measures.
PMID: 24033910 [PubMed - as supplied by publisher]
Stroke; a journal of cerebral circulation 2013 Jun
Authors: Mould WA, Carhuapoma JR, Muschelli J, Lane K, Morgan TC, McBee NA, Bistran-Hall AJ, Ullman NL, Vespa P, Martin NA, Awad I, Zuccarello M, Hanley DF, MISTIE Investigators,
Perihematomal edema (PHE) can worsen outcomes after intracerebral hemorrhage (ICH). Reports suggest that blood degradation products lead to PHE. We hypothesized that hematoma evacuation will reduce PHE volume and that treatment with recombinant tissue-type plasminogen activator (rt-PA) will not exacerbate it.
Minimally invasive surgery and rt-PA in ICH evacuation (MISTIE) phase II tested safety and efficacy of hematoma evacuation after ICH. We conducted a semiautomated, computerized volumetric analysis on computed tomography to assess impact of hematoma removal on PHE and effects of rt-PA on PHE. Volumetric analyses were performed on baseline stability and end of treatment scans.
Seventy-nine surgical and 39 medical patients from minimally invasive surgery and rt-PA in ICH evacuation phase II (MISTIE II) were analyzed. Mean hematoma volume at end of treatment was 19.6±14.5 cm(3) for the surgical cohort and 40.7±13.9 cm(3) for the medical cohort (P<0.001). Edema volume at end of treatment was lower for the surgical cohort: 27.7±13.3 cm(3) than medical cohort: 41.7±14.6 cm(3) (P<0.001). Graded effect of clot removal on PHE was observed when patients with >65%, 20% to 65%, and <20% ICH removed were analyzed (P<0.001). Positive correlation between PHE reduction and percent of ICH removed was identified (ρ=0.658; P<0.001). In the surgical cohort, 69 patients underwent surgical aspiration and rt-PA, whereas 10 underwent surgical aspiration only. Both cohorts achieved similar clot reduction: surgical aspiration and rt-PA, 18.9±14.5 cm(3); and surgical aspiration only, 24.5±14.0 cm(3) (P=0.26). Edema at end of treatment in surgical aspiration and rt-PA was 28.1±13.8 cm(3) and 24.4±8.6 cm(3) in surgical aspiration only (P=0.41).
Hematoma evacuation is associated with significant reduction in PHE. Furthermore, PHE does not seem to be exacerbated by rt-PA, making such neurotoxic effects unlikely when the drug is delivered to intracranial clot.
PMID: 23709739 [PubMed - as supplied by publisher]
World neurosurgery 2013 Feb 1
Authors: Morgan TC, Dawson J, Spengler D, Lees KR, Aldrich C, Mishra NK, Lane K, Quinn TJ, Diener-West M, Weir CJ, Higgins P, Rafferty M, Kinsley K, Ziai W, Awad I, Walters MR, Hanley D, CLEAR and VISTA Investigators,
Simple and rapid measures of intraventricular hemorrhage (IVH) volume are lacking. We developed and validated a modification of the original Graeb scale to facilitate rapid assessment of IVH over time.
We explored the relationship between the modified Graeb scale (mGS), original Graeb scale, measured IVH volume, and outcome using data from the Clot Lysis: Evaluating Accelerated Resolution of Hemorrhage with rtPA B (CLEAR B) study. We also explored its reliability. We then evaluated the relationship between mGS and outcome in a large sample of participants with IVH using data contained within the Virtual International Stroke Trials Archive (VISTA). We defined outcome using the modified Rankin scale (>3 signifying poor outcome).
The CLEAR B study included 360 scans from 36 subjects. The mGS score and IVH volume were highly correlated (R = 0.80, P<0.0001, R(2) 0.65). Baseline mGS was predictive of poor outcome (area under receiving operating characteristic curve 0.74, 95% confidence interval, 0.57-0.91), whereas the original Graeb scale was not. The VISTA study included 399 participants. Each unit increase in the mGS led to a 12% increase in the odds of a poor outcome (odds ratio, 1.12; 95% confidence interval, 1.05-1.19). Measures of reliability (intra- and inter- reader) were good in both studies.
The mGS, a semiquantitative scale for IVH volume measurement, is a reliable measure with prognostic validity suitable for rapid use in clinical practice and in research.
PMID: 23376381 [PubMed - as supplied by publisher]
Neurosurgery 2012 Oct
PMID: 23162828 [PubMed - as supplied by publisher]