Department of Neurology, Mayo Clinic, Jacksonville, FL, USA.
Citations 64
Letter by Freeman and Taussky Regarding Article, “Near Infrared Spectroscopy for the Detection of Desaturations in Vulnerable Ischemic Brain Tissue: A Pilot Study at the Stroke Unit Bedside”
Object Near-infrared spectroscopy (NIRS) offers noninvasive bedside measurement of direct regional cerebral arteriovenous (mixed) brain oxygenation. To validate the accuracy of this monitoring technique, the authors analyzed the statistical correlation of NIRS and CT perfusion with respect to regional cerebral blood flow (CBF) measurements. Methods The authors retrospectively reviewed all cases in which NIRS measurements were obtained at a single, academic neurointensive care unit from February 2008 to June 2011 in which CT perfusion was performed at the same time as NIRS data was collected. Regions of interest were obtained 2.5 cm below the NIRS bifrontal scalp probe on CT perfusion with an average volume between 2 and 4 ml, with mean CBF values used for purposes of analysis. Linear regression analysis was performed for NIRS and CBF values. Results The study included 8 patients (2 men, 6 women), 6 of whom suffered subarachnoid hemorrhage, 1 ischemic stroke, and 1 intracerebral hemorrhage and brain edema. Mean CBF measured by CT perfusion was 61 ml/100 g/min for the left side and 60 ml/100 g/min for the right side, while mean NIRS values were 75 on the right and 74 on the left. Linear regression analysis demonstrated a statistically significant probability value (p < 0.0001) comparing NIRS frontal oximetry and CT perfusion–obtained CBF values. Conclusions The authors demonstrated a linear correlation for frontal NIRS cerebral oxygenation measurements compared with regional CBF on CT perfusion imaging. Thus, frontal NIRS cerebral oxygenation measurement may serve as a useful, noninvasive, bedside intensive care unit monitoring tool to assess brain oxygenation in a direct manner.
The Diffuse Hyperdense Intracranial Circulation Sign
Letter by Freeman et al Regarding Article, “Very Early Mobilization After Stroke Fast-Tracks Return to Walking: Further Results From the Phase II AVERT Randomized Controlled Trial”
Abstractα‐Methyl‐acyl‐CoA‐racemase (AMACR) deficiency (OMIM 604489) is a rare peroxisomal disorder with a variable age of onset from infancy to late adulthood. We describe a 45‐year‐old male with a history of seizures who presented with relapsing encephalopathy. Laboratory studies revealed an elevated serum pristanic acid concentration, an elevated pristanic/phytanic acid ratio, as well as the previously described homozygous mutation in the AMACR gene, c.154T>C, consistent with AMACR deficiency. This homozygous mutation is associated with a variable phenotype ranging from neonatal cholestasis to late‐onset sensorimotor neuropathy. Dietary pristanic acid restriction was attempted to improve clinical status and the patient has remained in remission for more than 16 months.
Anticoagulation Therapy for Cardioembolic Stroke Prevention in the Elderly: Defining Benefits and Risks
Background and Purpose— Recombinant Factor VIIa decreases hematoma growth after spontaneous intracerebral hemorrhage (ICH) and rapidly decreases international normalized ratios in patients on warfarin but is also associated with an increased risk for thromboembolic complications. In this study, we assessed the risk of thromboembolic events in patients receiving recombinant Factor VIIa after ICH associated with warfarin treatment. Methods— We reviewed the medical charts, laboratory data, and radiological findings of consecutive patients with anticoagulation-related hemorrhages of the central nervous system who received recombinant Factor VIIa at Mayo Clinic Rochester and Mayo Clinic Florida between 2002 and 2009. The primary end point was the frequency of new thromboembolic events, including myocardial infarction, deep vein thrombosis, ischemic stroke, and pulmonary embolism. Results— We identified 101 patients; 54% had ICH and 30% subdural hematomas. The most common indications for anticoagulation were atrial fibrillation, deep vein thrombosis, and prosthetic valve. Thirteen patients (12.8%) had new thromboembolic events (10 deep vein thromboses and 3 ischemic strokes) within 90 days after recombinant Factor VIIa administration. Eight of these adverse events occurred within 2 weeks of treatment. In patients with ICH, the rate of thromboembolic complications was 5% and all events were venous. Conclusion— The risk of thromboembolic events in patients who received recombinant Factor VIIa for anticoagulation-associated ICH was not higher than that seen in patients treated for spontaneous ICH in the Factor Seven for Acute Hemorrhagic Stroke (FAST) trial. Spontaneous deep vein thrombosis was the most common complication in our series.