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Background and Purpose-Concerns persist regarding the safety of tissue plasminogen activator (tPA) therapy for acute ischemic stroke. Numerous case series of clinical experience with tPA have been published that provide additional data on the safety of thrombolytic therapy. Methods-This is a meta-analysis of 15 published, open-label studies that broadly followed approved indications and guidelines for tPA use in nonselective patient populations. Results-In 2639 treated patients, the symptomatic intracerebral hemorrhage rate was 5.2% (95% confidence interval, 4.3 to 6.0), slightly lower than the 6.4% rate in the treated group of the randomized, placebo-controlled National Institute of Neurological Disorders and Stroke (NINDS) trial. The mean total death rate (13.4%) and proportion of subjects achieving a very favorable outcome (37.1%) were comparable to the NINDS trial results.

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Previous studies of human stroke by 1H nuclear magnetic resonance spectroscopy have shown elevation of lactate lasting 3 to 6 months. Complete metabolic turnover of the elevated lactate pool has been demonstrated 5 weeks after a stroke. Its cellular localization is among the first questions requiring clarification. Information pertinent to this question came to us from a patient with a 2-week-old stroke by 1H nuclear magnetic resonance spectroscopic imaging 1 week before his death led to neuropathologic examination of the brain. 1H spectra from voxels including the infarcts showed increased lactate and decreased N-acetylaspartate. Histopathology showed sheets of foamy macrophages in the infarct, but few neurons. Macrophage density ranged from 196 cells/mm2 near the surface of the infarct to 788 near its medial margin. Glial density was 500 to 800 cells/mm2. Lactate concentration in voxels including portions of the infarct was estimated at 7 to 14 mM. Voxels showing low N-acetylaspartate and high lactate on spectroscopic imaging were associated with histopathologic sections containing foamy macrophages. Brain macrophages--which begin to appear 3 days after infarction and gradually disappear over several months--could be a major source of elevated lactate signals that persist for months after stroke.

This paper represents the opinion of a group of researchers and clinicians with an established interest in poststroke care and is based on the recognised need for long-term care following stroke, especially in view of the global increase of disability due to stroke. Among the more frequent long-term complications following stroke are spasticity-related disabilities. Although spasticity alone occurs in up to 60% of stroke survivors, disabling spasticity affects only 4-10%. Spasticity further interferes with important functions of daily life when it occurs in association with pain, motor impairment, and overall declines of cognitive and neurological function. It is proposed that the aftermath of stroke be considered a chronic disease requiring a multifactorial and multilevel approach. There are, however, knowledge gaps related to the prediction and recognition of poststroke disability. Interventions to prevent or minimise such disabilities require further development and evaluation. Poststroke spasticity research should focus on reducing disability and be considered as part of a continuum of chronic care requirements and should be recognised as a part of a comprehensive poststroke disease management programme.

Background-A panel of experts developed stroke rehabilitation guidelines for the Veterans Health Administration andDepartment of Defense Medical Systems. Methods-Starting from previously established guidelines, the panel evaluated published literature through 2002, using criteria developed by the US Preventive Services Task Force. Recommendations were based on evidence from randomized clinical trials, uncontrolled studies, or consensus expert opinion if definitive data were lacking. Results-Recommendations with Level I evidence include the delivery of poststroke care in a multidisciplinary rehabilitation setting or stroke unit, early patient assessment via the NIH Stroke Scale, early initiation of rehabilitation therapies, swallow screening testing for dysphagia, an active secondary stroke prevention program, and proactive prevention of venous thrombi. Standardized assessment tools should be used to develop a comprehensive treatment plan appropriate to each patient's deficits and needs. Medical therapy for depression or emotional lability is strongly recommended. A speech and language pathologist should evaluate communication and related cognitive disorders and provide treatment when indicated. The patient, caregiver, and family are essential members of the rehabilitation team and should be involved in all phases of the rehabilitation process. These recommendations are available in their entirety at http://stroke.ahajournals.org/cgi/content/full/36/9/e100. Evidence tables for each of the recommendations are also in the full document. Conclusions-These recommendations should be equally applicable to stroke patients receiving rehabilitation in all medical system settings and are not based on clinical problems or resources unique to the Federal Medical System.

Background and Purpose: Proton magnetic resonance spectroscopy can measure in vivo brain lactate and other metabolites noninvasively. We measured the biochemical changes accompanying stroke in 16 human subjects with cortical or deep cerebral infarcts within the first 3 weeks after symptom onset, and performed follow-up studies on six.Methods: One-dimensional proton spectroscopic imaging encompassing the infarct region was performed with a 2.1-T whole-body magnet using the stimulated echo pulse sequence and an echo time of 270 msec.Results: All but one of the cortical stroke patients had increased lactate within or near the infarct. Persistently elevated cerebral lactate was documented in five of six cases studied serially as long as 251 days after infarction. iV-acetylaspartate levels were decreased in most cortical strokes. Elevated lactate, accompanied by minimal reduction in iV-acetylaspartate, was recorded in two of four patients in the first week following a small subcortical infarct.Conclusions: Long-term elevation of lactate commonly occurs after stroke. This lactate may arise from ongoing ischemia or infiltrating leukocytes, or it may be a residual of the lactate formed during the initial insult. The ability to observe stroke-elevated lactate pools at any time after lesion onset provides an approach to distinguishing among these possibilities in the future. (Stroke 1992;23:333-340) KEY WORDS • cerebral infarction • lactates • nuclear magnetic resonance

A novel approach is presented for imaging macromolecule and metabolite signals in brain by proton magnetic resonance spectroscopic imaging. The method differentiates between metabolites and macromolecules by T1 weighting using an inversion pulse followed by a variable inversion recovery time before localization and spectroscopic imaging. In healthy subjects, the major macromolecule resonances at 2.05 and 0.9 ppm were mapped at a nominal spatial resolution of 1 x 1 x 1.5 cm3 and were demonstrated to be highly reproducible between subjects. In subacute stroke patients, a highly elevated macromolecule resonance at 1.3 ppm was mapped to infarcted brain regions, suggesting potential applications for studying pathological conditions.