Josser E. Delgado Almandoz

Systematic characterization of the computed tomography angiography spot sign in primary intracerebral hemorrhage identifies patients at highest risk for hematoma expansion: the spot sign score.

Background and Purpose— The presence of active contrast extravasation (the spot sign) on computed tomography (CT) angiography has been recognized as a predictor of hematoma expansion in patients with intracerebral hemorrhage. We aim to systematically characterize the spot sign to identify features that are most predictive of hematoma expansion and construct a spot sign scoring system. Methods— We retrospectively reviewed CT angiograms performed in all patients who presented to our emergency department over a 9-year period with primary intracerebral hemorrhage and had a follow-up noncontrast head CT within 48 hours of the baseline CT angiogram. Three neuroradiologists reviewed the CT angiograms and determined the presence and characteristics of spot signs according to strict radiological criteria. Baseline and follow-up intracerebral hemorrhage volumes were determined by computer-assisted volumetric analysis. Results— We identified spot signs in 71 of 367 CT angiograms (19%), 6 of which were delayed spot signs (8%). The presence of any spot sign increased the risk of significant hematoma expansion (69%, OR=92, P<0.0001). Among the spot sign characteristics examined, the presence of ≥3 spot signs, a maximum axial dimension ≥5 mm, and maximum attenuation ≥180 Hounsfield units were independent predictors of significant hematoma expansion, and these were subsequently used to construct the spot sign score. In multivariate analysis, the spot sign score was the strongest predictor of significant hematoma expansion, independent of time from ictus to CT angiogram evaluation. Conclusion— The spot sign score predicts significant hematoma expansion in primary intracerebral hemorrhage. If validated in other data sets, it could be used to select patients for early hemostatic therapy.

The Spot Sign Score in Primary Intracerebral Hemorrhage Identifies Patients at Highest Risk of In-Hospital Mortality and Poor Outcome among Survivors

Background and Purpose— The spot sign score is a potent predictor of hematoma expansion in patients with primary intracerebral hemorrhage (ICH). We aim to determine the accuracy of this scoring system for the prediction of in-hospital mortality and poor outcome among survivors in patients with primary ICH. Methods— Three neuroradiologists retrospectively reviewed CT angiograms (CTAs) performed in 573 consecutive patients who presented to our Emergency Department with primary ICH over a 9-year period to determine the presence and scoring of spot signs according to strict criteria. Baseline ICH and intraventricular hemorrhage volumes were independently determined by computer-assisted volumetric analysis. Medical records were independently reviewed for baseline clinical characteristics and modified Rankin Scale (mRS) at hospital discharge and 3-month follow-up. Poor outcome among survivors was defined as a mRS ≥4 at 3-month follow-up. Results— We identified spot signs in 133 of 573 CTAs (23.2%), 11 of which were delayed spot signs (8.3%). The presence of any spot sign increased the risk of in-hospital mortality (55.6%, OR 4.0, 95% CI 2.6 to 5.9, P<0.0001) and poor outcome among survivors at 3-month follow-up (50.8%, OR 2.5, 95% CI 1.4 to 4.3, P<0.0014). The spot sign score successfully predicted an escalating risk of both outcome measures. In multivariate analysis, the spot sign score was an independent predictor of in-hospital mortality (OR 1.5, 95% CI 1.2 to 1.9, P<0.0002) and poor outcome among survivors at 3-month follow-up (OR 1.6, 95% CI 1.1 to 2.1, P<0.0065). Conclusion— The spot sign score is an independent predictor of in-hospital mortality and poor outcome among survivors in primary ICH.

Pre-procedure P2Y12 reaction units value predicts perioperative thromboembolic and hemorrhagic complications in patients with cerebral aneurysms treated with the Pipeline Embolization Device

Background There is wide variability in the reported incidence of perioperative thromboembolic (0–14%) and hemorrhagic (0–11%) complications after Pipeline Embolization Device (PED) procedures for cerebral aneurysm treatment, which could be partly due to differences in patient response to the P2Y12 receptor antagonist administered while the PED endothelializes. This study aims to identify an optimal pre-procedure P2Y12 reaction units (PRU) value range and determine the independent predictors of perioperative thromboembolic and hemorrhagic complications after PED procedures. Methods We recorded patient and aneurysm characteristics, P2Y12 receptor antagonist administered, pre-procedure PRU value with VerifyNow, procedural variables and perioperative thromboembolic and hemorrhagic complications up to postoperative day 30 after PED procedures at our institution during an 8-month period. Perioperative complications were considered major if they caused a permanent disabling neurological deficit or death. Multivariate regression analysis was performed to identify independent predictors of perioperative complications in our cohort. Results Forty-four patients underwent 48 PED procedures at our institution during the study period. There were eight thromboembolic and hemorrhagic perioperative complications in our cohort (16.7%), four of which were major (8.3%). A pre-procedure PRU value of <60 or >240 (p=0.02) and a technically difficult procedure (p=0.04) were independent predictors of all perioperative complications. A pre-procedure PRU value of <60 or >240 (p=0.004) and a history of hypertension (p=0.03) were independent predictors of major perioperative complications. Conclusions In our cohort, a pre-procedure PRU value of <60 or >240 was the strongest independent predictor of all and major perioperative thromboembolic and hemorrhagic complications after PED procedures.

CT Angiography for Intracerebral Hemorrhage Does Not Increase Risk of Acute Nephropathy

Background and Purpose— CT angiography (CTA) is receiving increased attention in intracerebral hemorrhage (ICH) for its role in ruling out vascular abnormalities and potentially predicting ongoing bleeding. Its use is limited by the concern for contrast induced nephropathy (CIN); however, the magnitude of this risk is not known. Methods— We performed a retrospective analysis of a prospectively collected cohort of consecutive patients with ICH presenting to a single tertiary care hospital from 2002 to 2007. Demographic, clinical, and radiographic data were prospectively collected for all patients. Laboratory data and clinical course over the first 48 hours were retrospectively reviewed. Acute nephropathy was defined as any rise in creatinine of >25% or >0.5 mg/dL, such that the highest creatinine value was above 1.5 mg/dL. Results— 539 patients presented during the study period and had at least 2 creatinine measurements. 348 (65%) received a CTA. Acute nephropathy developed in 6% of patients who received a CTA and in 10% of those who did not (P=0.1). Risk of nephropathy was 14% in those receiving no contrast (130 patients), 5% in those receiving 1 contrast study (124 patients), and 6% in those receiving >1 contrast study (244 patients). Neither CTA nor any use of contrast predicted nephropathy in univariate or multivariate analysis. Conclusion— The risk of acute nephropathy after ICH was not increased by use of CTA. Studies of CIN that do not include a control group may overestimate the influence of contrast. Patients with ICH appear to have an 8% risk of developing “Hospital-Acquired Nephropathy.”

Variability in initial response to standard clopidogrel therapy, delayed conversion to clopidogrel hyper-response, and associated thromboembolic and hemorrhagic complications in patients undergoing endovascular treatment of unruptured cerebral aneurysms

Background and purpose Variability in response to clopidogrel therapy is increasingly being recognized as an important factor in thromboembolic and hemorrhagic complications encountered after neurointerventional procedures. This study aims to determine the variability in response to clopidogrel therapy and associated complications in patients undergoing endovascular treatment of unruptured cerebral aneurysms. Methods We recorded baseline patient characteristics, co-administered medications, P2Y12 reaction units (PRU) values with VerifyNow, clopidogrel dosing, and thromboembolic and hemorrhagic complications in patients undergoing endovascular treatment of unruptured cerebral aneurysms at our institution during a 19 month period. Results 100 patients were included in the study, 76 women and 24 men, mean age 57.3 years. 15 patients exhibited an initial clopidogrel hypo-response (PRU >240) and 21 patients an initial clopidogrel hyper-response (PRU <60). 36 patients had a follow-up VerifyNow test performed without changes to the standard 75 mg daily clopidogrel dose, which demonstrated that 59% of patients who had initially been within the target 60–240 PRU range exhibited a delayed conversion to clopidogrel hyper-response. In our cohort, a clopidogrel hypo-response was associated with a significantly increased risk of thromboembolic complications in patients undergoing cerebral aneurysm treatment with stent assistance or the pipeline embolization device (60%, p=0.003), while a clopidogrel hyper-response was associated with a significantly increased risk of major hemorrhagic complications in all patients undergoing endovascular treatment of cerebral aneurysms (11%, p=0.016). Conclusions We found wide and dynamic variability in response to clopidogrel therapy in patients undergoing endovascular treatment of unruptured cerebral aneurysms, which was significantly associated with thromboembolic and major hemorrhagic complications in our cohort.

Accuracy of Susceptibility-Weighted Imaging for the Detection of Arteriovenous Shunting in Vascular Malformations of the Brain

Background and Purpose— To determine the accuracy of susceptibility-weighted MRI (SWI) for the detection of arteriovenous shunting (AVS) in vascular malformations of the brain (BVM). Methods— We retrospectively identified 60 patients who had been evaluated for known or suspected BVM by both SWI and digital subtraction angiography, without intervening treatment, during a 3-year period. SWI images were retrospectively assessed by 2 independent reviewers for the presence of AVS as determined by the presence of signal hyperintensity within a venous structure in the vicinity of the BVM. Discrepancies were resolved by consensus among a panel of 3 neuroradiologists. Accuracy parameters of SWI for the detection of AVS were calculated using digital subtraction angiography as the reference standard. Results— A total of 80 BVM were identified in the 60 patients included in our study. Of the 29 BVM with AVS on digital subtraction angiography, 14 were untreated arteriovenous malformations, 10 were previously treated arteriovenous malformations, and 5 were untreated dural arteriovenous fistulas. Overall, SWI was 93% sensitive and 98% specific for the detection of AVS in BVM, with excellent interobserver agreement (&kgr;=0.94). In the 14 previously treated arteriovenous malformations, SWI was 100% sensitive and specific for the detection of AVS. In the 28 BVM associated with intracerebral hemorrhage, SWI was 100% sensitive and 96% specific for the detection of AVS. Conclusions— SWI is accurate for the detection of arteriovenous shunting in vascular malformations of the brain and, for some patients, SWI may offer a noninvasive alternative to angiography in screening for or follow-up of treated BVM.

Initial hospital management of patients with emergent large vessel occlusion (ELVO): report of the standards and guidelines committee of the Society of NeuroInterventional Surgery

Objective To summarize the current literature regarding the initial hospital management of patients with acute ischemic stroke (AIS) secondary to emergent large vessel occlusion (ELVO), and to offer recommendations designed to decrease the time to endovascular treatment (EVT) for appropriately selected patients with stroke. Methods Using guidelines for evidenced-based medicine proposed by the Stroke Council of the American Heart Association, a critical review of all available medical literature supporting best initial medical management of patients with AIS secondary to ELVO was performed. The purpose was to identify processes of care that most expeditiously determine the eligibility of a patient with an acute stroke for interventions including intravenous fibrinolysis with recombinant tissue plasminogen activator (IV tPA) and EVT using mechanical embolectomy. Results This review identifies four elements that are required to achieve timely revascularization in ELVO. (1) In addition to non-contrast CT (NCCT) brain scan, CT angiography should be performed in all patients who meet an institutional threshold for clinical stroke severity. The use of any advanced imaging beyond NCCT should not delay the administration of IV tPA in eligible patients. (2) Activation of the neurointerventional team should occur as soon as possible, based on either confirmation of large vessel occlusion or a prespecified clinical severity threshold. (3) Additional imaging techniques, particularly those intended to physiologically select patients for EVT (CT perfusion and diffusion–perfusion mismatch imaging), may provide additional value, but should not delay EVT. (4) Routine use of general anesthesia during EVT procedures, should be avoided if possible. These workflow recommendations apply to both primary and comprehensive stroke centers and should be tailored to meet the needs of individual institutions. Conclusions Patients with ELVO are at risk for severe neurologic morbidity and mortality. To achieve the best possible clinical outcomes stroke centers must optimize their triage strategies. Strategies that provide patients with ELVO with the fastest access to reperfusion depend upon detail-oriented process improvement.

Prospective Validation of the Computed Tomographic Angiography Spot Sign Score for Intracerebral Hemorrhage

Background and Purpose— Intracerebral hemorrhage (ICH) results in high mortality and morbidity for patients. Previous retrospective studies correlated the spot sign score (SSSc) with ICH expansion, mortality, and clinical outcome among ICH survivors. We performed a prospective study to validate the SSSc for the prediction of ICH expansion, mortality, and clinical outcome among survivors. Methods— We prospectively included consecutive patients with primary ICH presenting to a single institution for a 1.5-year period. All patients underwent baseline noncontrast computed tomography (CT) and multidetector CT angiography performed within 24 hours of admission and a follow-up noncontrast CT within 48 hours after the initial CT. The ICH volume was calculated on the noncontrast CT images using semiautomated software. The SSSc was calculated on the multidetector CT angiographic source images. We assessed in-hospital mortality and modified Rankin Scale at discharge and at 3 months among survivors. A multivariate logistic regression analysis was performed to determine independent predictors of hematoma expansion, in-hospital mortality, and poor clinical outcome. Results— A total of 131 patients met the inclusion criteria. Of the 131 patients, a spot sign was detected in 31 patients (24%). In a multivariate analysis, the SSSc predicted significant hematoma expansion (odds ratio, 3.1; 95% confidence interval, 1.77–5.39; P⩽0.0001), in-hospital mortality (odds ratio, 4.1; 95% confidence interval, 2.11–7.94; P⩽0.0001), and poor clinical outcome (odds ratio, 3; 95% confidence interval, 1.4–4.42; P=0.004). In addition, the SSSc was an accurate grading scale for ICH expansion, modified Rankin Scale at discharge, and in-hospital mortality. Conclusions— The SSSc demonstrated a strong stepwise correlation with hematoma expansion and clinical outcome in patients with primary ICH.

Diagnostic yield of repeat catheter angiography in patients with catheter and computed tomography angiography negative subarachnoid hemorrhage.

BACKGROUND The yield of repeat catheter angiography in patients with subarachnoid hemorrhage (SAH) who have negative initial catheter and computed tomography (CT) angiograms is not well understood. OBJECTIVE To determine the yield of repeat catheter angiography in a prospective cohort of patients with SAH and negative initial catheter and CT angiograms. METHODS From January 1, 2005, until September 1, 2010, we instituted a prospective protocol in which patients with SAH documented by noncontrast CT (NCCT) or cerebrospinal fluid (CSF) xanthochromia and negative initial catheter and CT angiograms were evaluated with repeat catheter angiography 7 days and 3 months after presentation to assess for causative vascular abnormalities. RESULTS Seventy-two patients were included, with a mean age of 53.1 years (median, 53.5 years; range, 19-88 years). Forty-six patients were female (63.9%) and 26 male (36.1%). Thirty-nine patients had nonperimesencephalic SAH (54.2%), 29 patients had perimesencephalic SAH (40.3%), and 4 patients had CSF xanthochromia (5.5%). The first repeat catheter angiogram performed 7 days after presentation demonstrated a causative vascular abnormality in 3 patients (yield of 4.2%), 2 of which had nonperimesencephalic SAH (yield of 5.1%), and 1 had perimesencephalic SAH (yield of 3.4%). The second repeat catheter angiogram performed in 43 patients (59.7%) did not demonstrate any causative vascular abnormalities. No causative abnormalities were found in patients with CSF xanthochromia. CONCLUSION Repeat catheter angiography performed 7 days after presentation is valuable in the evaluation of patients with SAH who have negative initial catheter and CT angiograms, demonstrating a causative vascular abnormality in 4.2% of patients.

Prevalence of Traumatic Dural Venous Sinus Thrombosis in High-Risk Acute Blunt Head Trauma Patients Evaluated with Multidetector CT Venography

PURPOSE To determine the prevalence of trauma-related dural venous sinus thrombosis (DVST) in high-risk patients with blunt head trauma who are examined with multidetector computed tomographic (CT) venography. MATERIALS AND METHODS With institutional review board approval, HIPAA compliance, and waived informed consent, the authors retrospectively studied the findings in 195 consecutive patients who presented to the emergency department with acute blunt head trauma and were examined with multidetector CT venography because they were considered to be at high risk for DVST owing to the presence of a fracture near a dural venous sinus or jugular bulb or a high index of clinical suspicion. Nonenhanced CT images and CT venograms were reviewed for the presence of skull fractures, intracranial hemorrhage, and traumatic DVST. Magnetic resonance and nonenhanced CT images subsequently obtained in patients with traumatic DVST were assessed for hemorrhagic venous infarctions. Statistical analyses were performed by using Student t and Pearson chi(2) tests. RESULTS Multidetector CT venography depicted thrombosis of 98 dural sinuses or jugular bulbs in 57 (40.7%) of the 140 patients with skull fractures extending to a dural sinus or jugular bulb. Fifty-four (55%) of the 98 sinuses or bulbs had occlusive thrombosis. DVST was seen in only those patients with skull fractures extending to a dural sinus or jugular bulb. Among the skull fractures extending to the transverse sinus, sigmoid sinus, or jugular bulb, those of the petrous temporal bone had a higher risk (50%, 36 of 72 fractures) of traumatic DVST than did those of the occipital bone (34% risk [32 of 93 fractures]) (P = .044). However, among the skull fractures extending to the superior sagittal sinus, those of the occipital bone had a higher risk (67% [eight of 12 fractures]) of traumatic DVST than did those of the parietal (39% risk [11 of 28 fractures]) and frontal (24% risk [four of 17 fractures]) bones (P = .065). Four (7%) patients with traumatic DVST had associated hemorrhagic venous infarctions, all secondary to occlusive DVST. CONCLUSION In patients with blunt head trauma, multidetector CT venographic evaluation should be performed only if there is a fracture extending to a dural venous sinus or jugular bulb.