Fan C F, Huang Y P, Li X, Chen Y, Li Z, Qiao S D
Department of Neurology, Peking University Shougang Hospital, Beijing 100041, China.
Department of Geriatrics, Peking University Shougang Hospital, Beijing 100041, China.
Beijing Da Xue Xue Bao Yi Xue Ban. 2023 Aug 18;55(4):762-765. doi: 10.19723/j.issn.1671-167X.2023.04.032.
Accurate and timely diagnosis of posterior circulation ischemic stroke is a challenge for emergency neurology clinicians, even MRI scan which is believed to be sensitive to acute ischemic lesions may be negative. It is particularly important to obtain the typical or characteristic symptoms and signs of the patients through comprehensive physical examination. We report a case of posterior inferior cerebellar artery (PICA) territory infarction with "episodic postural diplopia" as the initial symptom, hoping that clinicians notice the vertical diplopia caused by the disfunction of otolith gravity conduction pathway, which is characterized by the degree of diplopia being affected by postural changes. A 44-year-old man was in hospital due to episodic postural diplopia for 4 months, dizziness and unstable walking for 5 days. In the past four months, the patient had endured episodic diplopia attack for 8 times when standing or walking, which could be relieved obviously while lying down and gradually disappeared within 5-10 minutes. He had not seen a doctor since the outbreak of the novel coronavirus. Five days before admission, diplopia worsened accompanying obvious vertigo, nausea and vomiting, left facial numbness, and hiccups. The diplopia could be relieved after taking the supine position, but not completely disappear as before. Physical examination showed a triad of ocular tilt response (OTR), namely static ocular rotation (SOT), skew deviation (SD) and head tilt (HT). And also subjective visual vertical (SVV) deviation was found. Those signs were considered for otolith gravity conduction system involvement. Combined with other clinical signs, such as Horner signs, crossed sensory disorders, ataxia, and MRI scan, it was easy to find the infarction was in the territory of the left PICA. The reasons for the patient's "episodic posi-tional diplopia" in the early stage of the disease were considered as follows: (1) the gravity was less affected in the supine position, the stimulation of the otolith gravity conduction pathway was reduced, so the degree of eye deviation was reduced in the supine position. (2) As an ischemic cerebrovascular disease, the patient experienced a process of transient ischemic attack (TIA) in the posterior circulation, the cerebral blood supply and the hypoperfusion of stenosis were increased after lying down, so the diplopia symptom disappeared. The upright-supine test was recommended for the patients with vertical diplopia. It was recommened to differentiate between otolith pathway involvement and diplopia caused by trochlear nerve palsy.
准确及时地诊断后循环缺血性卒中对急诊神经内科临床医生来说是一项挑战，即使是被认为对急性缺血性病变敏感的MRI扫描也可能呈阴性。通过全面的体格检查获取患者典型或特征性的症状和体征尤为重要。我们报告一例以“发作性姿势性复视”为首发症状的小脑后下动脉（PICA）区域梗死病例，希望临床医生注意到由耳石重力传导通路功能障碍引起的垂直性复视，其特点是复视程度受姿势变化影响。一名44岁男性因发作性姿势性复视4个月、头晕及行走不稳5天入院。在过去4个月里，患者站立或行走时经历了8次发作性复视，躺下时可明显缓解，并在5 - 10分钟内逐渐消失。自新型冠状病毒爆发以来他未就医。入院前5天，复视加重，伴有明显眩晕、恶心呕吐、左侧面部麻木及呃逆。仰卧位后复视可缓解，但不像以前那样完全消失。体格检查发现眼倾斜反应（OTR）三联征，即静态眼旋转（SOT）、斜视（SD）和头倾斜（HT）。还发现主观视觉垂直（SVV）偏差。这些体征提示耳石重力传导系统受累。结合其他临床体征，如霍纳征、交叉性感觉障碍、共济失调以及MRI扫描，很容易发现梗死位于左侧PICA区域。患者疾病早期出现“发作性姿势性复视”的原因如下：（1）仰卧位时重力影响较小，耳石重力传导通路受到的刺激减少，所以仰卧位时眼偏斜程度降低。（2）作为缺血性脑血管病，患者后循环经历了短暂性脑缺血发作（TIA）过程，躺下后脑部供血及狭窄处的低灌注增加，所以复视症状消失。对于垂直性复视患者建议进行直立 - 仰卧试验。建议鉴别耳石通路受累与滑车神经麻痹引起的复视。
