Neurol Sci (2015) 36:1957–1959 DOI 10.1007/s10072-015-2298-7
LETTER TO THE EDITOR
Critical MRI markers in transient ischemic attack Thomas Ritzenthaler1,3 • Tae-Hee Cho1,3 • Guy Louis-Tisserand2 Yves Berthezene2,3 • Norbert Nighoghossian1,3
•
Received: 13 April 2015 / Accepted: 15 June 2015 / Published online: 8 July 2015 Ó Springer-Verlag Italia 2015
Keywords Acute ischemic stroke Intravenous thrombolysis MRI Sir, Several risk scores have been developed to predict early occurrence of stroke after transient ischemic attack (TIA). However, the presence of abnormal findings on brain magnetic resonance imaging (MRI) still requires validation to predict subsequent stroke after TIA. We present herein an unusual combination of MRI markers suggesting a high risk of stroke in the presence of a TIA. A 44-year-old man, without relevant past medical history, was admitted 3.5 h after a transient aphasia and right hemicorporal hypesthesia lasting 10 min. On admission, National Institute of Health Stroke Scale (NIHSS) score was 0, without other neurological impairment. The patient was in sinus rhythm, blood pressure was recorded at 120/80 mmHg. An emergency multimodal 3T MRI was performed (Achieva, Philips Medical System). Diffusion-Weighted Imaging revealed a left insular infarction, and MR angiography a proximal left middle cerebral artery (MCA) & Thomas Ritzenthaler [email protected] Norbert Nighoghossian [email protected] 1
Service d’Urgences Neurovasculaires, Hoˆpital Pierre Wertheimer, Hospices Civils de Lyon, 59 Bd Pinel, 69677 Bron, France
2
Service de Neuroradiologie, Hoˆpital Pierre Wertheimer, Hospices Civils de Lyon, Bron, France
3
CREATIS CNRS UMR 5220, INSERM U1044, Universite´ Lyon 1, Villeurbanne, France
occlusion. Perfusion-Weighted MRI found hypoperfused tissue in all the superficial MCA territory, consistent with a large hemispheric mismatch. T2*-weighted MRI showed a susceptibility vessel sign (SVS) within proximal left MCA and a brush sign (BS) consistent with enlargement of medullary veins. Fluid-Attenuated Inversion Recovery (FLAIR) sequence revealed FLAIR vascular hyperintensities suggesting the presence of slow flow through retrograde leptomeningeal collaterals. Intravenous rt-Pa was administered 4 h after symptom onset. The patient presented no clinical fluctuation. A second MRI performed 3 h after thrombolysis showed a partial recanalization of the proximal occlusion, with persistent occlusion in some insular branches of the MCA. A slight hypoperfusion remains in the posterior territory of MCA (Fig. 1). NIHSS score remained 0. Follow-up CT Angiography scan performed at day 1, revealed left MCA patency with minimal left insular hypodensity. The patient left the stroke unit asymptomatic at day 5. Etiological workup failed to find a stroke etiology. In the last years, an increasing number of reports have suggested that a preselection of patients with multimodal MRI protocols can identify patients with stroke who may benefit from intravenous thrombolysis within and beyond 4.30 h after symptom onset. Multimodal brain MRI demonstrates that neuroimaging findings of tissue injuries may be more important predictors of clinical outcome than arbitrary time thresholds or initial clinical pattern. MRI is particularly a key factor in the therapeutic decision in minor stroke [1]. In this case, MRI provides a set of potentially threatening imaging markers in the context of TIA: proximal arterial occlusion is an important predictor of early neurological deterioration in patients with acute mild stroke [2], combined diffusion and perfusion MRI reveals a large area of mismatch suggesting an impending
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Neurol Sci (2015) 36:1957–1959
Fig. 1 Admission MRI revealing left insular infarct (a), with hypoperfusion within the superficial middle cerebral artery territory [increasing MTT (b) and CBV (c)], and proximal middle cerebral artery occlusion (d); FLAIR vascular hyperintensity (e); susceptibility
vessel sign (f) and brush sign (g). MRI performed 3 h after rt-Pa revealing stability of ischemic lesion (h), and improvement of hypoperfusion (i, j) with recanalization of the middle cerebral artery (k)
stroke [3], FLAIR vascular hyperintensities indicating diminished reserve because symptomatic arterial occlusive disease is highly predictive of ischemic stroke after TIA [4] and finally, the brush sign (BS) detected on T2*weighted MRI may predict ischemic stroke and worsening before discharge [5]. Although the presence of abnormal findings on brain MRI still requires validation to predict stroke after TIA, acute assessment of TIAs involving the search of these imaging markers can provide useful results to prevent an impending stroke. After a TIA, a noninvasive intracranial vascular study is recommended to exclude proximal occlusion. If an occlusion is found, we suggest that additional MRI sequences could be performed, especially perfusion-weighted and T2*-weighted MRI, to highlight tissue at risk of necrosis that could be saved with recanalization.
Compliance with ethical standards
123
Conflict of interest of interest.
The authors declare that they have no conflict
References 1. Kruetzelmann A, Siemonsen S, Gerloff C, Rosenkranz M, Rother J, Fiehler J, Thomalla G (2009) Thrombolysis targeting MRI defined tissue at risk in minor stroke. J Neurol Neurosurg Psychiatry 80:1156–1158 2. Kim J-T, Park M-S, Chang J, Lee JS, Choi K-H, Cho K-H (2013) Proximal arterial occlusion in acute ischemic stroke with low NIHSS scores should not be considered as mild stroke. PLoS One 8:e70996 3. Mlynash M, Olivot J-M, Tong DC, Lansberg MG, Eyngorn I, Kemp S, Moseley ME, Albers GW (2009) Yield of combined perfusion and diffusion MR imaging in hemispheric TIA. Neurology 72:1127–1133
Neurol Sci (2015) 36:1957–1959 4. Kobayashi J, Uehara T, Toyoda K, Endo K, Ohara T, Fujinami J, Nagatsuka K, Minematsu K (2013) Clinical significance of fluidattenuated inversion recovery vascular hyperintensities in transient ischemic attack. Stroke J Cereb Circ 44:1635–1640
1959 5. Terasawa Y, Yamamoto N, Morigaki R, Fujita K, Izumi Y, Satomi J, Harada M, Nagahiro S, Kaji R (2014) Brush sign on 3-T T2*weighted MRI as a potential predictor of hemorrhagic transformation after tissue plasminogen activator therapy. Stroke 45:274–276
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LETTER TO THE EDITOR
Critical MRI markers in transient ischemic attack Thomas Ritzenthaler1,3 • Tae-Hee Cho1,3 • Guy Louis-Tisserand2 Yves Berthezene2,3 • Norbert Nighoghossian1,3
•
Received: 13 April 2015 / Accepted: 15 June 2015 / Published online: 8 July 2015 Ó Springer-Verlag Italia 2015
Keywords Acute ischemic stroke Intravenous thrombolysis MRI Sir, Several risk scores have been developed to predict early occurrence of stroke after transient ischemic attack (TIA). However, the presence of abnormal findings on brain magnetic resonance imaging (MRI) still requires validation to predict subsequent stroke after TIA. We present herein an unusual combination of MRI markers suggesting a high risk of stroke in the presence of a TIA. A 44-year-old man, without relevant past medical history, was admitted 3.5 h after a transient aphasia and right hemicorporal hypesthesia lasting 10 min. On admission, National Institute of Health Stroke Scale (NIHSS) score was 0, without other neurological impairment. The patient was in sinus rhythm, blood pressure was recorded at 120/80 mmHg. An emergency multimodal 3T MRI was performed (Achieva, Philips Medical System). Diffusion-Weighted Imaging revealed a left insular infarction, and MR angiography a proximal left middle cerebral artery (MCA) & Thomas Ritzenthaler [email protected] Norbert Nighoghossian [email protected] 1
Service d’Urgences Neurovasculaires, Hoˆpital Pierre Wertheimer, Hospices Civils de Lyon, 59 Bd Pinel, 69677 Bron, France
2
Service de Neuroradiologie, Hoˆpital Pierre Wertheimer, Hospices Civils de Lyon, Bron, France
3
CREATIS CNRS UMR 5220, INSERM U1044, Universite´ Lyon 1, Villeurbanne, France
occlusion. Perfusion-Weighted MRI found hypoperfused tissue in all the superficial MCA territory, consistent with a large hemispheric mismatch. T2*-weighted MRI showed a susceptibility vessel sign (SVS) within proximal left MCA and a brush sign (BS) consistent with enlargement of medullary veins. Fluid-Attenuated Inversion Recovery (FLAIR) sequence revealed FLAIR vascular hyperintensities suggesting the presence of slow flow through retrograde leptomeningeal collaterals. Intravenous rt-Pa was administered 4 h after symptom onset. The patient presented no clinical fluctuation. A second MRI performed 3 h after thrombolysis showed a partial recanalization of the proximal occlusion, with persistent occlusion in some insular branches of the MCA. A slight hypoperfusion remains in the posterior territory of MCA (Fig. 1). NIHSS score remained 0. Follow-up CT Angiography scan performed at day 1, revealed left MCA patency with minimal left insular hypodensity. The patient left the stroke unit asymptomatic at day 5. Etiological workup failed to find a stroke etiology. In the last years, an increasing number of reports have suggested that a preselection of patients with multimodal MRI protocols can identify patients with stroke who may benefit from intravenous thrombolysis within and beyond 4.30 h after symptom onset. Multimodal brain MRI demonstrates that neuroimaging findings of tissue injuries may be more important predictors of clinical outcome than arbitrary time thresholds or initial clinical pattern. MRI is particularly a key factor in the therapeutic decision in minor stroke [1]. In this case, MRI provides a set of potentially threatening imaging markers in the context of TIA: proximal arterial occlusion is an important predictor of early neurological deterioration in patients with acute mild stroke [2], combined diffusion and perfusion MRI reveals a large area of mismatch suggesting an impending
123
1958
Neurol Sci (2015) 36:1957–1959
Fig. 1 Admission MRI revealing left insular infarct (a), with hypoperfusion within the superficial middle cerebral artery territory [increasing MTT (b) and CBV (c)], and proximal middle cerebral artery occlusion (d); FLAIR vascular hyperintensity (e); susceptibility
vessel sign (f) and brush sign (g). MRI performed 3 h after rt-Pa revealing stability of ischemic lesion (h), and improvement of hypoperfusion (i, j) with recanalization of the middle cerebral artery (k)
stroke [3], FLAIR vascular hyperintensities indicating diminished reserve because symptomatic arterial occlusive disease is highly predictive of ischemic stroke after TIA [4] and finally, the brush sign (BS) detected on T2*weighted MRI may predict ischemic stroke and worsening before discharge [5]. Although the presence of abnormal findings on brain MRI still requires validation to predict stroke after TIA, acute assessment of TIAs involving the search of these imaging markers can provide useful results to prevent an impending stroke. After a TIA, a noninvasive intracranial vascular study is recommended to exclude proximal occlusion. If an occlusion is found, we suggest that additional MRI sequences could be performed, especially perfusion-weighted and T2*-weighted MRI, to highlight tissue at risk of necrosis that could be saved with recanalization.
Compliance with ethical standards
123
Conflict of interest of interest.
The authors declare that they have no conflict
References 1. Kruetzelmann A, Siemonsen S, Gerloff C, Rosenkranz M, Rother J, Fiehler J, Thomalla G (2009) Thrombolysis targeting MRI defined tissue at risk in minor stroke. J Neurol Neurosurg Psychiatry 80:1156–1158 2. Kim J-T, Park M-S, Chang J, Lee JS, Choi K-H, Cho K-H (2013) Proximal arterial occlusion in acute ischemic stroke with low NIHSS scores should not be considered as mild stroke. PLoS One 8:e70996 3. Mlynash M, Olivot J-M, Tong DC, Lansberg MG, Eyngorn I, Kemp S, Moseley ME, Albers GW (2009) Yield of combined perfusion and diffusion MR imaging in hemispheric TIA. Neurology 72:1127–1133
Neurol Sci (2015) 36:1957–1959 4. Kobayashi J, Uehara T, Toyoda K, Endo K, Ohara T, Fujinami J, Nagatsuka K, Minematsu K (2013) Clinical significance of fluidattenuated inversion recovery vascular hyperintensities in transient ischemic attack. Stroke J Cereb Circ 44:1635–1640
1959 5. Terasawa Y, Yamamoto N, Morigaki R, Fujita K, Izumi Y, Satomi J, Harada M, Nagahiro S, Kaji R (2014) Brush sign on 3-T T2*weighted MRI as a potential predictor of hemorrhagic transformation after tissue plasminogen activator therapy. Stroke 45:274–276
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