From the Stroke Program, Department of Neurology, University of Texas
Health Science Center, Houston, Tex.
Correspondence to James C. Grotta, MD, Department of Neurology, Rm 7.044, University of Texas Health Science Center, 6431 Fannin, Houston, TX 77030. E-mail jgrotta{at}neuro.med.uth.tmc.edu
Subjects and Methods—Patients with suspected hemispheric stroke
who fulfilled entry criteria into the National Institute of
Neurological Disorders and Stroke (NINDS) rt-PA Stroke Study and also
had pretreatment injection of 99mTc-HMPAO, with
single-photon emission computed tomography (SPECT) performed using a
triple-head camera at baseline and 24 hours, were included.
Results—All 12 patients who qualified for rtPA therapy had
perfusion defects on baseline SPECT (SPECT graded scale [SGS] score
range, 16 to 79). Mean±SD perfusion defect was comparable in rtPA
(n=4)versus placebo (n=5) groups (SGS score, 36±18 versus 39±12; NS)
despite earlier injection time in the rtPA group (98±24 versus 141±21
minutes; P=.02). Total SPECT scanning time was 20 to 25
minutes. At 24 hours, reperfusion was greater in rtPA patients compared
with the placebo group (SGS score, 7±9 versus 29±17;
P=.05), with relative improvement in the
region-of-interest scores of 87±16% after rtPA compared with 28±30%
with placebo (P=.01).
Conclusions—A substantial perfusion defect exists in stroke
patients with larger hemispheric infarcts who meet NINDS criteria for
rtPA therapy, and rtPA is better able than placebo to rectify this
defect. SPECT is feasible for clinical trials and should be evaluated
as a substituted end point in stroke therapeutic trials.
SPECT Methodology
The 4 rtPA and 5 placebo patients had comparable baseline SGS scores
(39±12 versus 36±18). Time to isotope injection was faster in the
rtPA group (98 ±24 versus 141±21 minutes; P=.02). Improved
perfusion occurred in both placebo and rtPA groups over the first 24
hours (Fig 1
One implication of our study is that clinical criteria alone without
confirmatory measurement of cerebral perfusion is sufficient to
establish that most patients who qualify for rtPA therapy on clinical
grounds also have a significant cerebral ischemic lesion. The
patient population in this SPECT study did not include those with brain
stem infarcts but did include patients suspected of having either
cortical or lacunar hemispheric strokes. However, only 1 of our
patients had a baseline National Institutes of Health Stroke Scale
score of <10 that might have been reflective of a smaller lacunar
lesion. Therefore, our conclusions are most valid in the consideration
of larger hemispheric lesions.
We2 and others3 4 5 6 7 8 9 10 11 12 13
have shown that SPECT measurement of cerebral perfusion correlates with
outcome and response to therapy. SPECT and other methodologies such as
positron emission tomography and nuclear magnetic resonance may
ultimately (after careful evaluation within the context of randomized
therapeutic trials) provide important information for patient
selection, especially to help exclude those with such severe and
irreversible damage that thrombolysis is ineffective or
dangerous. However, our data indicate that at least within the first 3
hours in patients with hemispheric infarcts, such studies are not
needed to establish that a perfusion defect exists which can possibly
be reversed by intravenous rtPA. This may not be the case
if patients are studied longer after the onset of symptoms, after
spontaneous reperfusion has occurred.
Our data also suggest that rtPA-induced reperfusion can be
documented by SPECT. In this small series we did not detect the
hyperemia described by other
investigators.6 Furthermore, such reperfusion
correlated with clinical improvement in our2 and
other3 4 5 6 7 8 9 10 11 12 13 published
studies.- This suggests the possibility of using
SPECT or other physiological measures as a
"substituted end point" for clinical trials. Such
physiological data may be more sensitive and
convenient and less expensive than long-term clinical follow-up, and at
the very least can provide important confirmatory information in
support of clinical outcome scales.
Received August 12, 1997;
revision received November 18, 1997;
accepted November 18, 1997.
2.
Hanson SK, Grotta JC, Rhoades H, Tran HD, Lamki
LM, Barron BJ, Taylor WJ. Value of single-photon emission computed
tomography in acute stroke therapeutic trials. Stroke. 1993;24:1322–1329.
3.
Baird AE, Donnan GA, Austin MC, Fitt GJ, Davis
SM, McKay WJ. Reperfusion after thrombolytic therapy in
ischemic stroke measured by single-photon emission
computed tomography. Stroke. 1994;25:79–85.[Abstract]
4.
Overgaard K, Sperling B, Boysen G, Pedersen H, Gam J,
Ellemann K, Karle A, Arlien-Soborg P, Olsen T, Videbaek C, Knudsen J.
Thrombolytic therapy in acute ischemic stroke:
Danish pilot study. Stroke. 1993;24:1439–1446.
5.
Hederschee D, Limburg M, van Royen EA, Hijdra A,
Buller HR, Koster PA. Thrombolysis with recombinant tissue
plasminogen activator in acute ischemic
stroke: evaluation with rCBF-SPECT. Acta Neurol Scand. 1991;83:317–322.[Medline]
[Order article via Infotrieve]
6.
Jorgensen HS, Sperling B, Nakayama H, Raaschou HO,
Olsen TS. Spontaneous reperfusion of cerebral infarcts in patients with
acute stroke. Arch Neurol. 1994;51:865–873.
7.
Infeld B, Davis SM, Donnan GA, Lichtenstein M, Baird
AE, Binns D, Mitchell PJ, Hopper JL. Streptokinase increases luxury
perfusion after stroke. Stroke. 1996;27:1524–1529.
8.
Davis SM, Chua MG, Lichtenstein M, Rossiter SC, Binns
D, Hopper JL. Cerebral hypoperfusion in stroke prognosis and brain
recovery. Stroke. 1993;24:1691–1696.
9.
Infeld B, Davis SM, Lichtenstein M, Mitchell PJ,
Hopper JL. Crossed cerebellar diaschisis and brain recovery from
stroke. Stroke. 1995;26:90–95.
10.
Giubilei F, Lenzi GL, Di Piero V, Pozzilli C, Pantano
P, Bastianello S, Argentino C, Fieschi C. Predictive value of brain
perfusion single-photon emission computed tomography in acute
ischemic stroke. Stroke. 1990;21:895–900.
11.
Brass LM, Walovitch R, Joseph J, Leveille J, Marchand
L, Hellman RS, Tikofsky RS, Masdeu JC, Hall KM, Van Heertum RL. The
role of single-photon emission computed tomography brain imaging with
mTc-bisicate in localization and definition of
mechanism of ischemic stroke. J Cereb Blood Flow
Metab. 1994;14:91–98.
12.
Laloux P, Richelle F, Jamart J, de Coster P, Laterre C.
Comparative correlations of HMPAO-SPECT indices, neurological
score, and stroke subtypes with clinical outcome in acute carotid
infarcts. Stroke. 1995;26:816–821.
13.
Limburg M, Van Royen EA, Hijdra A, Verbeeten B Jr.
rCBF-SPECT in brain infartion: when does it predict outcome?
J Nucl Med. 1991;32:382–387.
14.
Shimosegawa E, Hatazawa J, Inugami A, Fujita H, Ogawa
T, Aizawa Y, Kanno I, Okudera T, Uemura K. Cerebral infarction within
six hours of onset: prediction of completed infarction with
technetium-99m-HMPAO SPECT. J Nucl Med. 1994;35:1097–1103.
© 1998 American Heart Association, Inc.
Original Contributions
tPA-Associated Reperfusion After Acute Stroke Demonstrated by SPECT
Abstract
Top
Abstract
Introduction
Subjects and Methods
Results
Discussion
References
Purpose—The aim of our study was
twofold: to determine the frequency and magnitude of perfusion defect
in stroke patients who qualify for rtPA therapy within 3 hours of
stroke onset and to determine the ability of rtPA to improve perfusion
by 24 hours.
Key Words: cerebral blood flow • plasminogen activator, tissue-type • reperfusion • stroke • tomography, emission computed
Introduction
Top
Abstract
Introduction
Subjects and Methods
Results
Discussion
References
Although rtPA therapy
within the first 3 hours after the onset of acute stroke symptoms
results in improved outcome, the urgency of this therapy precludes
extensive diagnostic studies before treatment. Therefore,
in the NINDS study that demonstrated the efficacy of rtPA, there was no
requirement to demonstrate a perfusion defect prior to treatment.
Furthermore, while it is assumed that the effectiveness of rtPA was due
to its ability to improve reperfusion during the immediate poststroke
period, this was not documented by comparing baseline with 24-hour
studies of cerebral blood flow in the rtPA versus placebo groups. At
our center, which was one of the participants in the NINDS rt-PA Stroke
Study, we tried to obtain SPECT cerebral perfusion studies at baseline
and after 24 hours in as many patients as possible during the study. We
report the baseline results in all 12 patients who had SPECT scans
carried out within 3 hours of symptom onset and the baseline compared
with 24-hour SPECT studies in all 5 placebo-treated and 4 rtPA-treated
patients.
Subjects and Methods
Top
Abstract
Introduction
Subjects and Methods
Results
Discussion
References
Selection of Patients
All patients admitted to Hermann Hospital (Houston, Tex), where
we carried out the NINDS rtPA study, were considered for inclusion. The
inclusion and exclusion criteria for the NINDS study have been
published1 and for the most part were the
inclusion and exclusion criteria for the present SPECT
analysis, because all patients studied with SPECT were being
considered simultaneously for inclusion into the NINDS rtPA
trial. In addition, to be included in this SPECT substudy, all patients
had to receive the injection of isotope
(99mTc-HMPAO) for SPECT within 3 hours of symptom
onset but before rtPA administration, all had to have technically
adequate SPECT scans carried out at baseline and again after 24 hours,
and all had to have suspected hemispheric infarcts. Of the 12 patients
meeting these criteria and included in this analysis, 8 were
randomized into the NINDS rtPA versus placebo study and one was treated
with open-label rtPA soon after the study was completed. Three were not
treated with thrombolytics. Some of these patients were
included in a previous publication2 that
validated our SPECT methodology and correlated results with clinical
outcome. The previous analysis did not focus on results within
the first 3 hours or compare rtPA versus placebo patients.
Our methods for carrying out SPECT and analyzing data have been
published.2 Briefly, all patients received 20 to
25 mCi 99mTc-HMPAO intravenously for
each study. This readily crosses the blood-brain barrier and rapidly
localizes in brain tissue in proportion to the blood flow and function
at the time of injection, with minimal redistribution within 8 hours.
Scanning was performed 1 to 5 hours after injection with use of a
3-headed rotating gamma camera (Trionix Corp). Four transverse images
(10.7-mm thick) were chosen that began just above the cerebellum
posteriorly and inferior temporal lobes anteriorly. Ten
truncated wedges were outlined on the cortex of each hemisphere on each
image; each wedge represented one ROI. Asymmetry in isotope
uptake was calculated by dividing the counts from a single ROI in the
symptomatic hemisphere by counts in the comparable
contralateral ROI. Each ROI received a score of from 0 to 10, with 0
representing <10% asymmetry; 1, 10 to 19% asymmetry, 2,
20 to 29% asymmetry, etc. The sum of all ROI scores (10 ROIs per
slicex4 slices) gave the SPECT graded scale (SGS), which
represents both the depth and extent of perfusion defect.
Results
Top
Abstract
Introduction
Subjects and Methods
Results
Discussion
References
All data are presented in Table 1
. The mean time to injection of isotope
after onset of symptoms was 114±45 minutes. All 12 patients with
symptoms of cerebral ischemia persisting for up to 3 hours had
a perfusion defect visible on SPECT. The mean SGS score for the 12
patients was 40±18 (range, 16 to 79).
View this table:
[in a new window]
Table 1. Comparison of SGS and NIHSS Scores at Baseline and 24 Hours by
Group ), but a perfusion defect
persisted at 24 hours in all placebo patients (mean SGS score, 29±17).
In comparison, flow was virtually normal by 24 hours in all but 1 rtPA
patient (mean SGS score, 7 ± 9; P=.05 versus placebo).
The percent improvement in SGS score was significantly greater in the
rtPA group compared with placebo (P=.01; Fig 2). The improved perfusion in rtPA versus
placebo-treated patients was paralleled by greater improvement, as
measured on the NIH Stroke Scale, over the first 24 hours (Fig 3).
View larger version (23K):
[in a new window]
Figure 1. SGS score at baseline compared with 24 hours in
rtPA and placebo patients. Notice that there is a substantial perfusion
defect at baseline in both rtPA and placebo patients and that
significant reperfusion by 24 hours occurs in rtPA but not placebo
patients.
View larger version (18K):
[in a new window]
Figure 2. There is significantly greater reperfusion
(expressed as percent improvement in SGS score from baseline to 24
hours) in rtPA patients than in placebo patients.
View larger version (86K):
[in a new window]
Figure 3. Placebo patient (four scans at left) had a
National Institutes of Health Stroke Scale (NIHSS) score of 25 and SGS
score of 44 at baseline (top). At 24 hours, the NIHSS score improved to
15, but the SGS score worsened to 54 (bottom). rtPA patient (four scans
at right) had an NIHSS score of 20 and SGS score of 60 at baseline
(top). At 24 hours, the NIHSS score was 6 and the SGS score 24, with
reperfusion of the penumbral region (arrow) in the middle cerebral
artery distribution (bottom).
Discussion
Top
Abstract
Introduction
Subjects and Methods
Results
Discussion
References
Our data demonstrate that in patients presenting with a
persisting neurological deficit for up to 3 hours after symptom onset
and who qualify for rtPA therapy using the NINDS criteria, a
substantial perfusion defect exists. Furthermore, our data also
demonstrate the ability of rtPA therapy to rectify this perfusion
defect compared with placebo. Although the number of patients included
in this study is very small, the data are consistent with
clinical response observed in our patients and with other studies of
cerebral perfusion and thrombolysis in the
literature.3 4 5
Selected Abbreviations and Acronyms
NINDS
=
National Institute of Neurological Disorders and Stroke
ROI
=
region of interest
(r)tPA
=
(recombinant) tissue plasminogen activator
SGS
=
SPECT graded scale
SPECT
=
single-photon emission computed tomography
99mTc-HMPAO
=
[99mTc]hexamethylpropylenamine oxime
References
Top
Abstract
Introduction
Subjects and Methods
Results
Discussion
References
1.
The National Institute of Neurological
Disorders and Stroke rt-PA Stroke Study Group. Tissue
plasminogen activator for acute
ischemic stroke. N Eng J Med. 1995;333:1588–1593.
This article has been cited by other articles:
 |
|
 |
|
  R. E. Latchaw, M. J. Alberts, M. H. Lev, J. J. Connors, R. E. Harbaugh, R. T. Higashida, R. Hobson, C. S. Kidwell, W. J. Koroshetz, V. Mathews, et al. Recommendations for Imaging of Acute Ischemic Stroke: A Scientific Statement From the American Heart Association Stroke, November 1, 2009; 40(11): 3646 - 3678. [Full Text] [PDF]
|
|
|
|
|
|
S. I. Savitz Cosmic Implications of NXY-059 Stroke, March 1, 2009; 40(3_suppl_1): S115 - S118. [Full Text] [PDF]
|
|
|
|
|
|
G. Tsivgoulis and A. Alexandrov Ultrasound-Enhanced Thrombolysis: From Bedside to Bench Stroke, May 1, 2008; 39(5): 1404 - 1405. [Full Text] [PDF]
|
|
|
|
 |
|
 H. P. Adams Jr, G. del Zoppo, M. J. Alberts, D. L. Bhatt, L. Brass, A. Furlan, R. L. Grubb, R. T. Higashida, E. C. Jauch, C. Kidwell, et al. Guidelines for the Early Management of Adults With Ischemic Stroke: A Guideline From the American Heart Association/American Stroke Association Stroke Council, Clinical Cardiology Council, Cardiovascular Radiology and Intervention Council, and the Atherosclerotic Peripheral Vascular Disease and Quality of Care Outcomes in Research Interdisciplinary Working Groups: The American Academy of Neurology affirms the value of this guideline as an educational tool for neurologists. Circulation, May 22, 2007; 115(20): e478 - e534. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
H. P. Adams Jr, G. del Zoppo, M. J. Alberts, D. L. Bhatt, L. Brass, A. Furlan, R. L. Grubb, R. T. Higashida, E. C. Jauch, C. Kidwell, et al. Guidelines for the Early Management of Adults With Ischemic Stroke: A Guideline From the American Heart Association/ American Stroke Association Stroke Council, Clinical Cardiology Council, Cardiovascular Radiology and Intervention Council, and the Atherosclerotic Peripheral Vascular Disease and Quality of Care Outcomes in Research Interdisciplinary Working Groups: The American Academy of Neurology affirms the value of this guideline as an educational tool for neurologists Stroke, May 1, 2007; 38(5): 1655 - 1711. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
E. A. Noser, H. M. Shaltoni, C. E. Hall, A. V. Alexandrov, Z. Garami, E. D. Cacayorin, J. K. Song, J. C. Grotta, and M. S. Campbell III Aggressive Mechanical Clot Disruption: A Safe Adjunct to Thrombolytic Therapy in Acute Stroke? Stroke, February 1, 2005; 36(2): 292 - 296. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. V. Alexandrov, C. E. Hall, L. A. Labiche, A. W. Wojner, and J. C. Grotta Ischemic Stunning of the Brain: Early Recanalization Without Immediate Clinical Improvement in Acute Ischemic Stroke Stroke, February 1, 2004; 35(2): 449 - 452. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
D. L. Brown, K. C. Johnston, D. P. Wagner, and E. C. Haley Jr Predicting Major Neurological Improvement With Intravenous Recombinant Tissue Plasminogen Activator Treatment of Stroke Stroke, January 1, 2004; 35(1): 147 - 150. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
H. P. Adams Jr, R. J. Adams, T. Brott, G. J. del Zoppo, A. Furlan, L. B. Goldstein, R. L. Grubb, R. Higashida, C. Kidwell, T. G. Kwiatkowski, et al. Guidelines for the Early Management of Patients With Ischemic Stroke: A Scientific Statement From the Stroke Council of the American Stroke Association Stroke, April 1, 2003; 34(4): 1056 - 1083. [Full Text] [PDF]
|
|
|
|
|
|
R. E. Latchaw, H. Yonas, G. J. Hunter, W. T.C. Yuh, T. Ueda, A. G. Sorensen, J. L. Sunshine, J. Biller, L. Wechsler, R. Higashida, et al. Guidelines and Recommendations for Perfusion Imaging in Cerebral Ischemia: A Scientific Statement for Healthcare Professionals by the Writing Group on Perfusion Imaging, From the Council on Cardiovascular Radiology of the American Heart Association Stroke, April 1, 2003; 34(4): 1084 - 1104. [Full Text] [PDF]
|
|
|
|
 |
|
 C Foerch, R Du Mesnil de Rochemont, O Singer, T Neumann-Haefelin, M Buchkremer, F E Zanella, H Steinmetz, and M Sitzer S100B as a surrogate marker for successful clot lysis in hyperacute middle cerebral artery occlusion J. Neurol. Neurosurg. Psychiatry, March 1, 2003; 74(3): 322 - 325. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
P. A. Lapchak, D. M. Araujo, D. Song, and J. A. Zivin The Nonpeptide Glycoprotein IIb/IIIa Platelet Receptor Antagonist SM-20302 Reduces Tissue Plasminogen Activator-Induced Intracerebral Hemorrhage After Thromboembolic Stroke Stroke, January 1, 2002; 33(1): 147 - 152. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. A. Molina, J. Montaner, S. Abilleira, J. F. Arenillas, M. Ribo, R. Huertas, F. Romero, and J. Alvarez-Sabin Time Course of Tissue Plasminogen Activator-Induced Recanalization in Acute Cardioembolic Stroke: A Case-Control Study Stroke, December 1, 2001; 32(12): 2821 - 2827. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. C. Grotta, K. M. A. Welch, S. C. Fagan, M. Lu, M. R. Frankel, T. Brott, S. R. Levine, P. D. Lyden, and P. D. Lyden Clinical Deterioration Following Improvement in the NINDS rt-PA Stroke Trial Stroke, March 1, 2001; 32(3): 661 - 668. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 V. Keris, S. Rudnicka, V. Vorona, G. Enina, B. Tilgale, and J. Fricbergs Combined Intraarterial/Intravenous Thrombolysis for Acute Ischemic Stroke AJNR Am. J. Neuroradiol., February 1, 2001; 22(2): 352 - 358. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
P. A. Lapchak, D. F. Chapman, and J. A. Zivin Pharmacological Effects of the Spin Trap Agents N-t-Butyl-Phenylnitrone (PBN) and 2,2,6,6-Tetramethylpiperidine-N-Oxyl (TEMPO) in a Rabbit Thromboembolic Stroke Model : Combination Studies With the Thrombolytic Tissue Plasminogen Activator Stroke, January 1, 2001; 32(1): 147 - 153. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 T. Brott and J. Bogousslavsky Treatment of Acute Ischemic Stroke N. Engl. J. Med., September 7, 2000; 343(10): 710 - 722. [Full Text] [PDF]
|
|
|
|
 |
|
 J. Rother, L. Jonetz-Mentzel, A. Fiala, J. R. Reichenbach, M. Herzau, W. A. Kaiser, and C. Weiller Hemodynamic Assessment of Acute Stroke Using Dynamic Single-Slice Computed Tomographic Perfusion Imaging Arch Neurol, August 1, 2000; 57(8): 1161 - 1166. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. Berrouschot, H. Barthel, S. Hesse, W. H. Knapp, D. Schneider, and R. von Kummer Reperfusion and Metabolic Recovery of Brain Tissue and Clinical Outcome After Ischemic Stroke and Thrombolytic Therapy Stroke, July 1, 2000; 31(7): 1545 - 1551. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
W. S. Burgin, M. Malkoff, R. A. Felberg, A. M. Demchuk, I. Christou, J. C. Grotta, and A. V. Alexandrov Transcranial Doppler Ultrasound Criteria for Recanalization After Thrombolysis for Middle Cerebral Artery Stroke Stroke, May 1, 2000; 31(5): 1128 - 1132. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. V. Alexandrov, A. M. Demchuk, R. A. Felberg, I. Christou, P. A. Barber, W. S. Burgin, M. Malkoff, A. W. Wojner, and J. C. Grotta High Rate of Complete Recanalization and Dramatic Clinical Recovery During tPA Infusion When Continuously Monitored With 2-MHz Transcranial Doppler Monitoring Stroke, March 1, 2000; 31(3): 610 - 614. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
W.-D. Heiss, L. Kracht, M. Grond, J. Rudolf, B. Bauer, K. Wienhard, and G. Pawlik Early [11C]Flumazenil/H2O Positron Emission Tomography Predicts Irreversible Ischemic Cortical Damage in Stroke Patients Receiving Acute Thrombolytic Therapy Stroke, February 1, 2000; 31(2): 366 - 369. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. M. Demchuk, T. H. Wein, R. A. Felberg, I. Christou, and A. V. Alexandrov Evolution of Rapid Middle Cerebral Artery Recanalization During Intravenous Thrombolysis for Acute Ischemic Stroke Circulation, November 30, 1999; 100(22): 2282 - 2283. [Full Text] [PDF]
|
|
|
|
 |
|
 A. V. Alexandrov and J. W. Norris SPECT in cerebrovascular disease Can. Med. Assoc. J., November 1, 1999; 161(9): 1135 - 1135. [Full Text] [PDF]
|
|
|
|
|
|
T. Ueda, S. Sakaki, Y. Kumon, and S. Ohta Multivariable Analysis of Predictive Factors Related to Outcome at 6 Months After Intra-Arterial Thrombolysis for Acute Ischemic Stroke Stroke, November 1, 1999; 30 (11): 2360 - 2365. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. Berrouschot, H. Barthel, J. Koster, S. Hesse, A. Rossler, W. H. Knapp, and D. Schneider Extracorporeal Rheopheresis in the Treatment of Acute Ischemic Stroke : A Randomized Pilot Study Stroke, April 1, 1999; 30(4): 787 - 792. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. M. Demchuk, R. A. Felburg, and A. V. Alexandrov Clinical Recovery from Acute Ischemic Stroke after Early Reperfusion of the Brain with Intravenous Thrombolysis N. Engl. J. Med., March 18, 1999; 340(11): 894 - 895. [Full Text]
|
|
|
|
|
|
P. Pantano, F. Caramia, L. Bozzao, C. Dieler, and R. von Kummer Delayed Increase in Infarct Volume After Cerebral Ischemia : Correlations with Thrombolytic Treatment and Clinical Outcome Stroke, March 1, 1999; 30(3): 502 - 507. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
P. A. Barber, S. M. Davis, B. Infeld, A. E. Baird, G. A. Donnan, D. Jolley, and M. Lichtenstein Spontaneous Reperfusion After Ischemic Stroke Is Associated With Improved Outcome Stroke, December 1, 1998; 29(12): 2522 - 2528. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. A. Meyer, J. Grotta, and A. Alexandrov Quantitative Brain SPECT and the NIH Stroke Scale • Response Stroke, July 1, 1998; 29(7): 1480 - 1480. [Full Text]
|
|
| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||