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Confined anterior cerebral artery infarction manifesting as isolated unilateral axial weakness
Journal of the Neurological Sciences 373 (2017) 18–20
Contents lists available at ScienceDirect
Journal of the Neurological Sciences journal homepage: www.elsevier.com/locate/jns
Clinical Short Communication
Confined anterior cerebral artery infarction manifesting as isolated unilateral axial weakness☆ Asaf Honig a, Ruth Eliahou b, Eitan Auriel c,⁎ a b c
Department of Neurology, Hadassah-Hebrew University Medical Center, Jerusalem, Israel Department of Radiology, Hadassah-Hebrew University Medical Center, Jerusalem, Israel Department of Neurology, Tel Aviv Sourasky Medical Center, Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
a r t i c l e
i n f o
Article history: Received 28 August 2016 Received in revised form 14 November 2016 Accepted 23 November 2016 Available online 25 November 2016 Keywords: Anterior cerebral artery infarction Axial weakness Neurological examination
a b s t r a c t We describe isolated unilateral axial weakness in three patients eventually diagnosed with anterior cerebral artery infarction (ACAI), a new clinical observation. Files of three ACAI patients (2 females, 1 male, ages 55–80) were retrospectively reviewed. All three presented to the ED with sudden unsteadiness. On initial neurological examination, all three patients manifested unilateral truncal deviation to the side contralateral to the weakness, even while seated. There was significant unilateral hypotonia due to substantial paravertebral weakness. None had pyramidal signs or increased limb tone. Speech, language, and cognitive performance were intact during admission examination. In all three patients, initial diffusion-weighted imaging (DWI) MRI showed small confined regions of restriction involving the posterolateral border of ACA territory; CT angiography was normal in one patient with a newly diagnosed atrial fibrillation but showed atherosclerotic vasculature with severe narrowing of the A3 segment of the ACA in two. Awareness of ACAI presenting as unilateral axial weakness is warranted. We suggest that optimal diagnostic management should include examination of axial tone. Ischemic involvement of distal ACA branches may herald a more extensive ACAI. Prompt diagnosis may enable thrombolysis or endovascular treatment, and blood pressure maintenance may allow adequate perfusion to damaged tissue. © 2016 Elsevier B.V. All rights reserved.
1. Introduction Anterior cerebral artery infarction (ACAI) may vary considerably in its clinical presentation [1]; thus, the diagnosis may be delayed and emergent therapeutic interventions may be precluded [1,2]. While sudden lower limb weakness, even confined to the distal leg, is well recognized as a presentation of ACAI [1,3,4], isolated axial weakness representing proximal motor involvement in ACAI was not well described. We suggest a new clinical observation of isolated unilateral axial weakness in three patients who were eventually diagnosed with ACAI. 2. Methods We retrospectively reviewed medical charts of three ACAI patients examined by us upon their initial Emergency Department (ED) ☆ Asaf Honig and Eitan Auriel conceptualized the study, drafted the manuscript, and analyzed clinical data. Ruth Eliahou assisted in analysis and interpretation of data. All authors read and approved the final version of the manuscript. Eitan Auriel has overall responsibility for data integrity. ⁎ Corresponding author at: Department of Neurology, Carmel Medical Center, Israel. E-mail addresses: [email protected] (A. Honig), [email protected] (R. Eliahou), [email protected] (E. Auriel).
http://dx.doi.org/10.1016/j.jns.2016.11.061 0022-510X/© 2016 Elsevier B.V. All rights reserved.
presentation during 2013–2014. The Institutional Review Board of the Hadassah-Hebrew University Medical Center approved the study design with a waiver of informed consent (HMO-09-0277). 3. Results Patient presentation is summarized in Table 1. The three patients (ages 55–80, two females) presented to the ED with sudden unsteadiness. Symptom onset was upon awakening in two patients and hyperacute while standing in the third. All three reported unilateral truncal deviations even while seated, and described a steady effort to exercise the axial musculature contralateral to their axial weakness in an attempt to remain seated. On initial neurological examination, the bodily posture of all three patients bent to the side contralateral to the weakness; bending forward or backward was impossible. Examination of axial tone revealed significant unilateral hypotonia due to substantial paravertebral weakness (1 on the Ashworth scale [5]). Consequent to loss of axial tone, marked skin folding was clearly evident on the affected side. Lower limb examination revealed no drift; however, during the examination of individual muscles, patient 3 showed fluctuating iliopsoas weakness. None had pyramidal signs or increased limb tone. Their speech, language, and cognitive performance were intact during the admission examination.
A. Honig et al. / Journal of the Neurological Sciences 373 (2017) 18–20
19
Table 1 Patient characteristics. Pt no.
Age, gender
Vascular risk factors
Previous medical treatment
Possible mechanism
Neuro-imaging
Management
NIHSS at discharge
mRS 90
Late sequelae, 1-year follow-up
1
80, F
Single antiplatelet therapy
LVA
CTA, diffuse LVA
Conservative
8
4
Motor weakness, focal epilepsy
2
60, M
Single antiplatelet therapy
LVA
CTA, diffuse LVA
Conservative
10
5
Motor weakness, abulia
3
56, F
DM HTN Choles DM HTN Choles HTN
None
Cardio-embolic
CTA normal
Aggressive MAP preservation
1
1
Axial instability
Abbreviations: CTA, CT angiography; Choles, Hypercholesterolemia; DM, Diabetes mellitus; F, Female; HTN, Hypertension; M, Male; MRS, Modified Rankin Scale; LVA, Large vessel atherosclerosis; NIHSS, National Institutes of Health Stroke Scale.
Patients 1 and 2 had multiple vascular risk factors (diabetes mellitus, hypertension, hypercholestesterolemia) while patient 3 had no elevated risk factors. In all three patients, initial diffusion-weighted imaging (DWI) MRI showed small confined regions of restriction involving the posterolateral border of ACA territory. (Fig. 1A–C, Fig. 2A–B). CT angiography (CTA) was normal in patient 3 but showed atherosclerotic vasculature in patients 1 and 2 with severe narrowing of the A3 segment of the ACA (Fig. 2C). Patient 3 had a newly diagnosed atrial fibrillation, but after a full examination no embolic source was identified in patients 1, 2. On follow-up, the two patients with atherosclerosis (patients 1, 2) gradually worsened and developed severe proximal leg paresis with relatively preserved distal motor strength compatible with an extensive ACAI, which was confirmed on follow-up MRI. Patient 1 developed
post-stroke epilepsy, patient 2 developed severe akinetic mutism, and patient 3 had a remarkable improvement albeit with residual postural instability of her torso. 4. Discussion To the best of our knowledge this is the first description of isolated unilateral axial weakness as an acute presentation of partial ACAI. Evaluation of the paravertebral motor functions is often overlooked on neurological exam in the acute setting, yet our three patients all presented with acute unilateral paravertebral weakness that could result in false localization. Axial dysfunction is most likely closely related to new lesions in the primary motor cortex on the precentral gyrus (Fig. 1D–F). We presume
Fig. 1. Patient 3 MRI ischemic lesions in a confined region of the primary motor cortex. (A) Axial diffusion-weighted imaging (DWI) MRI for patient 3, a 55-year-old female. Note the focus of restricted diffusion in the cortical/subcortical median precentral gyrus in the posterior frontal lobe, anterior cerebral artery (ACA) territory. (B–C) Sagittal and coronal reconstructions of the DWI MRI study for patient 3. (D) *The motor cortical homunculus, a physical representation of the human body located in the primary motor cortex in the precentral gyrus. *Courtesy OpenStax College - Anatomy & Physiology, Connexions Web site (available at https://commons.wikimedia.org/w/index.php?curid=30148008. Accessed July 5, 2016).
20
A. Honig et al. / Journal of the Neurological Sciences 373 (2017) 18–20
Fig. 2. Patients 1 and 2. Axial diffusion-weighted imaging (DWI) MRI for patient 1, an 80-year-old female, and for patient 2 (B) a 60-year-old male. (C) CT angiography (CTA) of patient 1 showing atherosclerotic vasculature with severe narrowing of the A3 segment of the ACA.
that the territory of the paracentral ACA branch arising from the A4–A5 segments of the callosomarginal artery was affected. The proposed mechanisms are hypoperfusion of end branches in the cerebral vasculature of patients 1 and 2 and embolism in patient 3. Of note, all three subjects had a small primary confined lesion involving exactly the same territory. As most ACAI result from an atherosclerotic disease [1], prompt diagnosis and treatment aimed to preserve mean arterial pressure might avoid or slow the stroke progression that we witnessed in patients 1, 2. The relatively small representation of the trunk in the motor homunculus (Fig. 1D) hampered detection of the new infarct by CT imaging. As a result, the diagnosis was made beyond the therapeutic window in patients 1 and 2, and they were left with full medial frontal syndrome. We suggest that early hemodynamic manifestation of ACAI may precede more extensive ACA involvement. This is of upmost importance, as ACAI is associated with severe behavioral, cognitive, and motor morbidity [1,2]. Possible differential diagnoses for acute unilateral axial weakness include hemiataxic syndrome caused by a lesion anywhere along the frontopontocerebellar axis [6]. Patients with ataxic hemiparesis have a substantial truncal ataxia and at first glance may seem similar to ACAI patients, who tend to fall while sitting unattended or standing. However, in contrast to ataxic hemiparesis patients, the ACAI patients previously described have a severe unilateral axial weakness and lack hemiparesis. Avoidance of such a false localization is of extreme importance, as ataxic hemiparesis syndrome is in most cases due to a lacunar stroke localizing to the pons or internal capsule [7], while ACAI patients may develop far more debilitating neurological sequelae. Nevertheless, we must still bear in mind that ataxic hemiparesis may also localize to the frontal lobe due to crossed cerebellar diaschisis, and those patients are also at risk of developing the full ACAI syndrome [8]. Pure gait apraxia without weakness is another differential diagnosis, but again patients lack unilateral axial weakness on examination [9]. 5. Conclusion Higher awareness of ACAI presenting as unilateral axial weakness is warranted. We suggest that optimal diagnostic management should
include examination of axial tone. Ischemic involvement of distal ACA branches may herald a more extensive ACAI. Prompt diagnosis may enable thrombolysis or endovascular treatment, and blood pressure maintenance may allow adequate perfusion to damaged tissue.
Disclosures The authors have conflicts of interest to disclose. The study was not supported by any sponsorship or outside funding.
Acknowledgements The authors wish to thank Shifra Fraifeld, a medical writer and research associate at the Hadassah-Hebrew University Medical Center, for her editorial assistance in the preparation of this manuscript. References [1] S.Y. Kang, J.S. Kim, Anterior cerebral artery infarction: stroke mechanism and clinicalimaging study in 100 patients, Neurology 70 (24 Pt 2) (2008) 2386–2393. [2] A. Arboix, L. Garcia-Eroles, N. Sellares, A. Raga, M. Oliveres, J. Massons, Infarction in the territory of the anterior cerebral artery: clinical study of 51 patients, BMC Neurol. 9 (2009) 30. [3] R. Schneider, J.C. Gautier, Leg weakness due to stroke. Site of lesions, weakness patterns and causes, Brain J. Neurol. 117 (Pt 2) (1994) 347–354. [4] B.D. Ku, E.J. Lee, H. Kim, Cerebral infarction producing sudden isolated foot drop, Journal of Clinical Neurology 3 (1) (2007) 67–69. [5] M. Blackburn, P. van Vliet, S.P. Mockett, Reliability of measurements obtained with the modified Ashworth scale in the lower extremities of people with stroke, Phys. Ther. 82 (1) (2002) 25–34. [6] J. Bogousslavsky, R. Martin, T. Moulin, Homolateral ataxia and crural paresis: a syndrome of anterior cerebral artery territory infarction, J. Neurol. Neurosurg. Psychiatry 55 (12) (1992) 1146–1149. [7] M.J. Gorman, R. Dafer, S.R. Levine, Ataxic hemiparesis: critical appraisal of a lacunar syndrome, Stroke; A Journal of Cerebral Circulation 29 (12) (1998) 2549–2555. [8] A.C. Flint, M.C. Naley, C.B. Wright, Ataxic hemiparesis from strategic frontal white matter infarction with crossed cerebellar diaschisis, Stroke; A Journal of Cerebral Circulation 37 (1) (2006) e1–e2. [9] S.E. Nadeau, Gait apraxia: further clues to localization, Eur. Neurol. 58 (3) (2007) 142–145.
Contents lists available at ScienceDirect
Journal of the Neurological Sciences journal homepage: www.elsevier.com/locate/jns
Clinical Short Communication
Confined anterior cerebral artery infarction manifesting as isolated unilateral axial weakness☆ Asaf Honig a, Ruth Eliahou b, Eitan Auriel c,⁎ a b c
Department of Neurology, Hadassah-Hebrew University Medical Center, Jerusalem, Israel Department of Radiology, Hadassah-Hebrew University Medical Center, Jerusalem, Israel Department of Neurology, Tel Aviv Sourasky Medical Center, Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
a r t i c l e
i n f o
Article history: Received 28 August 2016 Received in revised form 14 November 2016 Accepted 23 November 2016 Available online 25 November 2016 Keywords: Anterior cerebral artery infarction Axial weakness Neurological examination
a b s t r a c t We describe isolated unilateral axial weakness in three patients eventually diagnosed with anterior cerebral artery infarction (ACAI), a new clinical observation. Files of three ACAI patients (2 females, 1 male, ages 55–80) were retrospectively reviewed. All three presented to the ED with sudden unsteadiness. On initial neurological examination, all three patients manifested unilateral truncal deviation to the side contralateral to the weakness, even while seated. There was significant unilateral hypotonia due to substantial paravertebral weakness. None had pyramidal signs or increased limb tone. Speech, language, and cognitive performance were intact during admission examination. In all three patients, initial diffusion-weighted imaging (DWI) MRI showed small confined regions of restriction involving the posterolateral border of ACA territory; CT angiography was normal in one patient with a newly diagnosed atrial fibrillation but showed atherosclerotic vasculature with severe narrowing of the A3 segment of the ACA in two. Awareness of ACAI presenting as unilateral axial weakness is warranted. We suggest that optimal diagnostic management should include examination of axial tone. Ischemic involvement of distal ACA branches may herald a more extensive ACAI. Prompt diagnosis may enable thrombolysis or endovascular treatment, and blood pressure maintenance may allow adequate perfusion to damaged tissue. © 2016 Elsevier B.V. All rights reserved.
1. Introduction Anterior cerebral artery infarction (ACAI) may vary considerably in its clinical presentation [1]; thus, the diagnosis may be delayed and emergent therapeutic interventions may be precluded [1,2]. While sudden lower limb weakness, even confined to the distal leg, is well recognized as a presentation of ACAI [1,3,4], isolated axial weakness representing proximal motor involvement in ACAI was not well described. We suggest a new clinical observation of isolated unilateral axial weakness in three patients who were eventually diagnosed with ACAI. 2. Methods We retrospectively reviewed medical charts of three ACAI patients examined by us upon their initial Emergency Department (ED) ☆ Asaf Honig and Eitan Auriel conceptualized the study, drafted the manuscript, and analyzed clinical data. Ruth Eliahou assisted in analysis and interpretation of data. All authors read and approved the final version of the manuscript. Eitan Auriel has overall responsibility for data integrity. ⁎ Corresponding author at: Department of Neurology, Carmel Medical Center, Israel. E-mail addresses: [email protected] (A. Honig), [email protected] (R. Eliahou), [email protected] (E. Auriel).
http://dx.doi.org/10.1016/j.jns.2016.11.061 0022-510X/© 2016 Elsevier B.V. All rights reserved.
presentation during 2013–2014. The Institutional Review Board of the Hadassah-Hebrew University Medical Center approved the study design with a waiver of informed consent (HMO-09-0277). 3. Results Patient presentation is summarized in Table 1. The three patients (ages 55–80, two females) presented to the ED with sudden unsteadiness. Symptom onset was upon awakening in two patients and hyperacute while standing in the third. All three reported unilateral truncal deviations even while seated, and described a steady effort to exercise the axial musculature contralateral to their axial weakness in an attempt to remain seated. On initial neurological examination, the bodily posture of all three patients bent to the side contralateral to the weakness; bending forward or backward was impossible. Examination of axial tone revealed significant unilateral hypotonia due to substantial paravertebral weakness (1 on the Ashworth scale [5]). Consequent to loss of axial tone, marked skin folding was clearly evident on the affected side. Lower limb examination revealed no drift; however, during the examination of individual muscles, patient 3 showed fluctuating iliopsoas weakness. None had pyramidal signs or increased limb tone. Their speech, language, and cognitive performance were intact during the admission examination.
A. Honig et al. / Journal of the Neurological Sciences 373 (2017) 18–20
19
Table 1 Patient characteristics. Pt no.
Age, gender
Vascular risk factors
Previous medical treatment
Possible mechanism
Neuro-imaging
Management
NIHSS at discharge
mRS 90
Late sequelae, 1-year follow-up
1
80, F
Single antiplatelet therapy
LVA
CTA, diffuse LVA
Conservative
8
4
Motor weakness, focal epilepsy
2
60, M
Single antiplatelet therapy
LVA
CTA, diffuse LVA
Conservative
10
5
Motor weakness, abulia
3
56, F
DM HTN Choles DM HTN Choles HTN
None
Cardio-embolic
CTA normal
Aggressive MAP preservation
1
1
Axial instability
Abbreviations: CTA, CT angiography; Choles, Hypercholesterolemia; DM, Diabetes mellitus; F, Female; HTN, Hypertension; M, Male; MRS, Modified Rankin Scale; LVA, Large vessel atherosclerosis; NIHSS, National Institutes of Health Stroke Scale.
Patients 1 and 2 had multiple vascular risk factors (diabetes mellitus, hypertension, hypercholestesterolemia) while patient 3 had no elevated risk factors. In all three patients, initial diffusion-weighted imaging (DWI) MRI showed small confined regions of restriction involving the posterolateral border of ACA territory. (Fig. 1A–C, Fig. 2A–B). CT angiography (CTA) was normal in patient 3 but showed atherosclerotic vasculature in patients 1 and 2 with severe narrowing of the A3 segment of the ACA (Fig. 2C). Patient 3 had a newly diagnosed atrial fibrillation, but after a full examination no embolic source was identified in patients 1, 2. On follow-up, the two patients with atherosclerosis (patients 1, 2) gradually worsened and developed severe proximal leg paresis with relatively preserved distal motor strength compatible with an extensive ACAI, which was confirmed on follow-up MRI. Patient 1 developed
post-stroke epilepsy, patient 2 developed severe akinetic mutism, and patient 3 had a remarkable improvement albeit with residual postural instability of her torso. 4. Discussion To the best of our knowledge this is the first description of isolated unilateral axial weakness as an acute presentation of partial ACAI. Evaluation of the paravertebral motor functions is often overlooked on neurological exam in the acute setting, yet our three patients all presented with acute unilateral paravertebral weakness that could result in false localization. Axial dysfunction is most likely closely related to new lesions in the primary motor cortex on the precentral gyrus (Fig. 1D–F). We presume
Fig. 1. Patient 3 MRI ischemic lesions in a confined region of the primary motor cortex. (A) Axial diffusion-weighted imaging (DWI) MRI for patient 3, a 55-year-old female. Note the focus of restricted diffusion in the cortical/subcortical median precentral gyrus in the posterior frontal lobe, anterior cerebral artery (ACA) territory. (B–C) Sagittal and coronal reconstructions of the DWI MRI study for patient 3. (D) *The motor cortical homunculus, a physical representation of the human body located in the primary motor cortex in the precentral gyrus. *Courtesy OpenStax College - Anatomy & Physiology, Connexions Web site (available at https://commons.wikimedia.org/w/index.php?curid=30148008. Accessed July 5, 2016).
20
A. Honig et al. / Journal of the Neurological Sciences 373 (2017) 18–20
Fig. 2. Patients 1 and 2. Axial diffusion-weighted imaging (DWI) MRI for patient 1, an 80-year-old female, and for patient 2 (B) a 60-year-old male. (C) CT angiography (CTA) of patient 1 showing atherosclerotic vasculature with severe narrowing of the A3 segment of the ACA.
that the territory of the paracentral ACA branch arising from the A4–A5 segments of the callosomarginal artery was affected. The proposed mechanisms are hypoperfusion of end branches in the cerebral vasculature of patients 1 and 2 and embolism in patient 3. Of note, all three subjects had a small primary confined lesion involving exactly the same territory. As most ACAI result from an atherosclerotic disease [1], prompt diagnosis and treatment aimed to preserve mean arterial pressure might avoid or slow the stroke progression that we witnessed in patients 1, 2. The relatively small representation of the trunk in the motor homunculus (Fig. 1D) hampered detection of the new infarct by CT imaging. As a result, the diagnosis was made beyond the therapeutic window in patients 1 and 2, and they were left with full medial frontal syndrome. We suggest that early hemodynamic manifestation of ACAI may precede more extensive ACA involvement. This is of upmost importance, as ACAI is associated with severe behavioral, cognitive, and motor morbidity [1,2]. Possible differential diagnoses for acute unilateral axial weakness include hemiataxic syndrome caused by a lesion anywhere along the frontopontocerebellar axis [6]. Patients with ataxic hemiparesis have a substantial truncal ataxia and at first glance may seem similar to ACAI patients, who tend to fall while sitting unattended or standing. However, in contrast to ataxic hemiparesis patients, the ACAI patients previously described have a severe unilateral axial weakness and lack hemiparesis. Avoidance of such a false localization is of extreme importance, as ataxic hemiparesis syndrome is in most cases due to a lacunar stroke localizing to the pons or internal capsule [7], while ACAI patients may develop far more debilitating neurological sequelae. Nevertheless, we must still bear in mind that ataxic hemiparesis may also localize to the frontal lobe due to crossed cerebellar diaschisis, and those patients are also at risk of developing the full ACAI syndrome [8]. Pure gait apraxia without weakness is another differential diagnosis, but again patients lack unilateral axial weakness on examination [9]. 5. Conclusion Higher awareness of ACAI presenting as unilateral axial weakness is warranted. We suggest that optimal diagnostic management should
include examination of axial tone. Ischemic involvement of distal ACA branches may herald a more extensive ACAI. Prompt diagnosis may enable thrombolysis or endovascular treatment, and blood pressure maintenance may allow adequate perfusion to damaged tissue.
Disclosures The authors have conflicts of interest to disclose. The study was not supported by any sponsorship or outside funding.
Acknowledgements The authors wish to thank Shifra Fraifeld, a medical writer and research associate at the Hadassah-Hebrew University Medical Center, for her editorial assistance in the preparation of this manuscript. References [1] S.Y. Kang, J.S. Kim, Anterior cerebral artery infarction: stroke mechanism and clinicalimaging study in 100 patients, Neurology 70 (24 Pt 2) (2008) 2386–2393. [2] A. Arboix, L. Garcia-Eroles, N. Sellares, A. Raga, M. Oliveres, J. Massons, Infarction in the territory of the anterior cerebral artery: clinical study of 51 patients, BMC Neurol. 9 (2009) 30. [3] R. Schneider, J.C. Gautier, Leg weakness due to stroke. Site of lesions, weakness patterns and causes, Brain J. Neurol. 117 (Pt 2) (1994) 347–354. [4] B.D. Ku, E.J. Lee, H. Kim, Cerebral infarction producing sudden isolated foot drop, Journal of Clinical Neurology 3 (1) (2007) 67–69. [5] M. Blackburn, P. van Vliet, S.P. Mockett, Reliability of measurements obtained with the modified Ashworth scale in the lower extremities of people with stroke, Phys. Ther. 82 (1) (2002) 25–34. [6] J. Bogousslavsky, R. Martin, T. Moulin, Homolateral ataxia and crural paresis: a syndrome of anterior cerebral artery territory infarction, J. Neurol. Neurosurg. Psychiatry 55 (12) (1992) 1146–1149. [7] M.J. Gorman, R. Dafer, S.R. Levine, Ataxic hemiparesis: critical appraisal of a lacunar syndrome, Stroke; A Journal of Cerebral Circulation 29 (12) (1998) 2549–2555. [8] A.C. Flint, M.C. Naley, C.B. Wright, Ataxic hemiparesis from strategic frontal white matter infarction with crossed cerebellar diaschisis, Stroke; A Journal of Cerebral Circulation 37 (1) (2006) e1–e2. [9] S.E. Nadeau, Gait apraxia: further clues to localization, Eur. Neurol. 58 (3) (2007) 142–145.