Parkinsonism and Related Disorders 30 (2016) 86e88 Contents lists available at ScienceDirect Parkinsonism and Related Disorders journal homepage: www.elsevier.com/locate/parkreldis Correspondence Recurrent episodes of isolated hemidystonia in a young adult: Dissectionassociated stenosis in the middle cerebral artery Keywords: Hemidystonia Dissection Middle cerebral artery Transient ischemic attack Dystonia is a hyperkinetic movement disorder, characterized by sustained involuntary muscle contractions leading to twisting or abnormal postures. Most cases of acquired hemidystonia result from brain lesions including stroke, trauma, or a tumor affecting the contralateral striato-thalamo-cortical pathway [1]. Besides, intermittent hemidystonia could be observed in patients with paroxysmal dystonia. However, to our knowledge, recurrent episodes of isolated hemidystonia, as the presenting symptom of transient ischemic attack (TIA), have not been reported. Herein, we report a case of hemidystonia with recurrent TIAs, likely resulting from dissection-associated stenosis in the middle cerebral artery (MCA). A 33-year-old man was admitted to our hospital because of recurrent hemidystonia in his left side. Two weeks prior, he felt sudden and sustained muscle contractions with abnormal twisting postures in his left face, arm, and leg that lasted several minutes. His wife, a nurse, observed this phenomenon, and mentioned that the involuntary movements were neither jerky, nor choreoathetoid. The episodes usually occurred twice a day; the first was when he came out of the bathroom around 7:20 a.m. after taking a hot shower, and the second episode occurred when he sat on the office chair between 4:00 p.m. and 5:00 p.m. while working as a banker all day long. His hemidystonic TIA was completely relieved after a few minutes by some motion such as massaging the left arm with his right hand. Blood sugar was not checked at the TIA time, and hemidystonia was improved without eating any food. His hemidystonia was considerably severe in the first three days, but moderately improved thereafter. He had no history of medication use, head trauma, or headache and denied any familial history of cerebrovascular disease. He has a 10 pack-year history of smoking, and is a social drinker. His neurological examination was unremarkable. Orthostatic hypotension was not detected during the hospitalized period, although the check of orthostatic blood pressure was not performed in the first day of his admission. Laboratory tests showed http://dx.doi.org/10.1016/j.parkreldis.2016.06.012 1353-8020/© 2016 Elsevier Ltd. All rights reserved. an increased erythrocyte sedimentation rate (ESR) (24 mm/hr; normal range ¼ ~ 0e10 mm/hr), but all other studies including his lipid profile and vasculitis workup (rheumatoid arthritis factor; anticardiolipin, antinuclear, and antineutrophil cytoplasmic antibodies) were unremarkable. He did not have diabetes mellitus and his HbA1c was 5.9% (normal range: 4.8e5.9%). BUN/creatinine ratio and hematocrit were unremarkable. Diffusion-weighted imaging (DWI) (Fig. 1A) and fluid attenuated inversion recovery (FLAIR) imaging (Fig. 1B) showed no definite abnormalities. However, cerebral angiography (Fig. 1C and G) revealed a severe shortsegment stenosis of the proximal M1 portion of the right MCA. There was no other stenosis or occlusive lesion from both intracranial and extracranial angiographic findings. Vessel wall imaging with high resolution MRI exhibited eccentric plaque with aneurysmal dilatation (Fig. 1D) and strong enhancement within the intramural hematoma (Fig. 1E and F), suggesting dissection with active inflammation. Computed tomography (CT) perfusion imaging demonstrated that the mean transit time in the right MCA territory was mildly delayed compared to the left MCA territory (Fig. 1I), but both blood volume (Fig. 1H) and blood flow (Fig. 1J) were relatively preserved, inferring compensatory perfusion in the right MCA territory. Immediately after admission, intravenous hydration was administered to improve cerebral perfusion. We treated him with oral drugs including aspirin 100 mg/day, pantoprazole 20 mg/day, atorvastatin 40 mg/day, and cilostazol 50 mg twice a day. There were no recurrent episodes of transient hemidystonia, and he was discharged from the hospital with those medications after a week. The patient has not experienced any TIA including hemidystonia or any other arterial dissection for 2 months follow-up period. Differential diagnosis of MCA stenosis includes atherosclerosis, dissection, Moyamoya, vasculitis, and reversible cerebral vasoconstriction syndrome [2]. The current patient is a 33-year-old Asian male with one stroke risk factor (smoking). High resolution MRI revealing eccentric plaques usually favor atherosclerosis, dissection, or occasionally, vasculitis. The patient’s laboratory tests revealed no evidence of vasculitis. Moreover, we observed intramural hematoma with aneurysmal dilatation. Collectively, the possibility of dissection is much higher than that of atherosclerosis, although we could not completely rule out atherosclerosis. Determining why the dissecting plaque (Fig. 1E and F) is sometimes enhanced remains uncertain, but such enhancement is likely active inflammation [3]. Additionally, the patient’s history and neuroimaging showed no evidence of multiple sclerosis. In respect with the etiology of the MCA dissection, since there were no predisposing factors including genetic background and head trauma, we Correspondence / Parkinsonism and Related Disorders 30 (2016) 86e88 87 Fig. 1. Brain magnetic resonance imaging (MRI) studies showed the dissecting stenosis in the right middle cerebral artery (MCA) (AeF); (A&B) Diffusion-weighted imaging (DWI) and fluid attenuated inversion recovery (FLAIR) imaging were unremarkable. (C) Time-of-flight (TOF) magnetic resonance angiography (MRA) showed severe stenosis in the right MCA (white arrow). (D) High resolution magnetic resonance imaging (MRI) revealed eccentric plaque (intramural hematoma) with aneurysmal dilatation (empty arrow), indicating MCA dissection. (E&F) The dissecting plaque was strongly enhanced, likely representing active inflammation (round ring). (G) 3D-dynamic computed tomography (CT) angiography confirmed the severe stenosis in the proximal MCA. CT perfusion study exhibited that the perfusion status in the right MCA territory was slightly decreased, compared to the left territory (HeJ); (H) Cerebral blood volume was not different between the MCA territories. (I) Mean transit time was slightly delayed in the right MCA territory (oval ring), compared to the left territory. (J) Cerebral blood flow was not different between the MCA territories, reflecting relative compensation in the right MCA perfusion. 88 Correspondence / Parkinsonism and Related Disorders 30 (2016) 86e88 supposed that the MCA dissection was spontaneously developed in this relatively young Asian male. In line with the literatures, spontaneous dissection of intracranial artery is not unusual among Asian people [4,5], although isolated MCA dissection is an extremely rare phenomenon. As a clinical manifestation of TIA, it is widely accepted that MCA stenosis could present as contralateral hemiplegia. In contrast, this patient showed severe stenosis in the right MCA with recurrent episodes of isolated hemidystonia in the left side. We supposed that the patient’s TIAs occurred during brain hypoperfusion; peripheral vasodilatation in the lower extremity could induce cerebral hypoperfusion after taking a hot shower, or while sitting for long periods. Furthermore, the dissecting plaque was located in the proximal part of the MCA, inferring that the lenticulostriate arteries, supplying the basal ganglia, could be crucially affected by cerebral hypoperfusion. Indeed, in the CT perfusion study (Fig. 1I and J), the mean transit time was mildly delayed in the right subcortex, rather than the cortex. Therefore, with respect to hypoperfusion state, the basal ganglia might be more affected rather than the corticospinal tract. Taken together, our findings suggest that transient ischemia in the basal ganglia could cause circuit dysfunction, resulting in hemidystonia in the contralateral side. In line with our findings, some have reported that TIAs, caused by occlusion of the MCA or internal cerebral artery, could present as involuntary movements including hemichorea [6] or hemichoreoathetosis with hemidystonia [7]. In conclusion, this is the first report of isolated hemidystonia presenting as recurrent TIAs. Conflict of interest The authors have no financial conflicts of interest. Acknowledgements This work was supported by the Soonchunhyang University Research Fund. References [1] C. Chuang, S. Fahn, S.J. Frucht, The natural history and treatment of acquired hemidystonia: report of 33 cases and review of the literature, J. Neurol. Neurosurg. Psychiatry 72 (1) (2002) 59e67. [2] Y.J. Choi, S.C. Jung, D.H. Lee, Vessel wall imaging of the intracranial and cervical carotid arteries, J. Stroke 17 (3) (2015) 238e255. [3] T. Pfefferkorn, T. Saam, A. Rominger, M. Habs, L.A. Gerdes, C. Schmidt, C. Cyran, A. Straube, J. Linn, K. Nikolaou, P. Bartenstein, M. Reiser, M. Hacker, M. Dichgans, Vessel wall inflammation in spontaneous cervical artery dissection: a prospective, observational positron emission tomography, computed tomography, and magnetic resonance imaging study, Stroke 42 (6) (2011) 1563e1568. [4] A. Arauz, A. Ruiz, G. Pacheco, P. Rojas, M. Rodriguez-Armida, C. Cantu, L. Murillo-Bonilla, J.L. Ruiz-Sandoval, F. Barinagarrenmenteria, Aspirin versus anticoagulation in intra- and extracranial vertebral artery dissection, Eur. J. Neurol. 20 (1) (2013) 167e172. [5] T. Tsukahara, K. Minematsu, Overview of spontaneous cervicocephalic arterial dissection in Japan, Acta Neurochir. Suppl. 107 (2010) 35e40. [6] T. Irioka, J. Ayabe, H. Mizusawa, Hemichorea improved by extracranialintracranial bypass surgery for middle cerebral artery occlusion, J. Neurol. 257 (10) (2010) 1756e1758. [7] J.Y. Li, P.H. Lai, N.J. Peng, Moyamoya disease presenting with hemichoreoathetosis and hemidystonia, Mov. Disord. 22 (13) (2007) 1983e1984. Jisang Park Department of Radiology, Soonchunhyang University Gumi Hospital, Soonchunhyang University School of Medicine, Republic of Korea Kyum-Yil Kwon* Department of Neurology, Soonchunhyang University Gumi Hospital, Soonchunhyang University School of Medicine, 1Gongdanro 179, Gumi, Kyeongsangbuk-do, 730-706, Republic of Korea * Corresponding author. E-mail addresses: denovo78@schmc.ac.kr, denovo78@naver.com (K.-Y. Kwon). 13 April 2016