分析并总结急性一氧化碳中毒患者的主因、病史、表现与体征、检查化验结果等，探究其临床特点及影像学表现。

临床特点分析：仔细分析并比较每例患者的临床特点；影像学表现分析：对每例患者进行颅脑磁共振成像（MRI）检查，了解急性一氧化碳中毒后颅内影像学改变及动态变化。

5例急性一氧化碳中毒患者（1例重症，4例轻症）碳氧血红蛋白（COHb）均显著升高，轻症者临床表现为头晕、一过性意识障碍、肢体抽搐等，重症者则表现为持续性意识障碍；部分患者出现白细胞、丙氨酸氨基转移酶（ALT）、肌酸激酶、肌钙蛋白、脑钠肽等化验指标明显偏高，其中重症患者简易精神状态检查（MMSE）量表评分、蒙特利尔认知评估（MoCA）量表评分等均显著低于正常值，提示其认知功能显著受损。影像学检查方面，重症患者颅脑MRI提示双侧大脑脚、苍白球异常信号（长T1、长T2），头CT显示双侧苍白球低密度病灶；而轻症患者颅脑MRI可见沿皮层广泛分布的弥散加权成像（DWI）序列高信号，且治疗后这种DWI信号的异常增高逐渐消失，考虑主要由缺血缺氧所致。

一氧化碳中毒患者应尽早诊断，及早治疗；急性期重症患者影像学表现为对称的苍白球、大脑脚异常信号；轻症患者主要表现为大脑皮质的缺氧缺血性改变。发病早期高压氧治疗对于防治一氧化碳中毒迟发型脑病、改善预后意义重大。

To characterize clinical and neuroimaging manifestations in acute carbon monoxide (CO) poisoning by analyzing etiology, symptomatology, laboratory profiles, and neuroimaging features.

Clinical characteristics analysis: each patient's exposure history, neurological symptoms, and laboratory tests were carefully analyzed and compared. Imaging analysis: each patient underwent cranial MRI to evaluate the intracranial imaging features and dynamics following acute CO poisoning.

Among the 5 patients with acute CO poisoning (1 severe case, 4 mild cases), COHb levels were significantly elevated. Patients with mild poisoning manifested clinical symptoms such as dizziness, transient consciousness disturbances, and limb convulsions, while the severe case exhibited persistent consciousness disturbances. Some patients showed elevated levels of laboratory indicators, including white blood cells, alanine aminotransferase, creatine kinase, troponin, and brain natriuretic peptide. Notably the severe patient demonstraed significantly lower mini-mental state examination (MMSE) and Montreal cognitive assessment (MoCA) scores compared to the normal range, indicative of notable cognitive impairment. In terms of imaging, MRI of the severe case revealed abnormal signals (long T1 and long T2) in the bilateral cerebral peduncle and globus pallidus, and CT of the head showed low-density lesions in the bilateral globus pallidus. For the mild cases, cranial MRI displayed widespread high signals in the diffusion weighted imaging (DWI) sequence along the cortex, which gradually disappeared after treatment, likely reflecting ischemic and hypoxic changes.

Early diagnosis and prompt treatment are imperative for patients with acute CO poisoning. In severe acute cases, imaging typically shows abnormal symmetrical signals in the globus pallidus and cerebral peduncles, whereas mild cases primarily exhibit hypoxic-ischemic changes in the cerebral cortex. Timely initiation of hyperbaric oxygen therapy during the acute phase is crucial for preventing delayed encephalopathy caused by CO poisoning and improving prognosis.