【作者】 杨雪；

【导师】 李光来；

【作者基本信息】 山西医科大学 ， 神经病学， 2010， 硕士

【摘要】 脊髓亚急性联合变性subacute combined degeneration of the spinal cord, SCD)是维生素B12缺乏引起的神经系统变性疾病,其主要累及脊髓后索、侧索和周围神经。典型临床表现为四肢或双下肢深感觉障碍、感觉性共济失调、痉挛性瘫痪和周围神经损害如肢体末端感觉异常等。以往脊髓亚急性联合变性的诊断主要依据典型临床表现与血液检查结果如血清维生素B12水平降低、巨幼细胞性贫血,对于血清维生素B12水平正常或临床表现不典型者则难以确诊。而脊髓亚急性联合变性病变早期临床症状常表现为多样性以及非特异性,使得诊断困难。本病一旦确诊,治疗方法简单有效,而延误诊断常导致严重的不可逆的神经功能缺损,有时甚至是致死性的。对本病进行早期诊断、早期治疗是降低其永久性神经功能损害的关键。但近来报道很多由于不典型的临床表现或是维生素B12正常水平而使得诊治延误的SCD病例,使得人们对旧的诊断依据提出质疑。同时随着电生理、影像学检查如肌电图、诱发电位、磁共振(magnetic resonance imaging,MRI)广泛应用于临床,人们对本病的认识不断加深,在电生理、影像学表现以及血生化检测指标等方面对于本病的诊断不断地有新的观点提出。本文复习近期多个文献资料,从病因病理、临床特点、辅助检查等多个方面对SCD作出详细描述,意在提高大家对SCD这一可治愈疾病的认识,帮助早期诊断。经综合多个文献资料得出以下认识：本病临床上并不少见；本病神经系统病变的严重程度与血清亚铁血红蛋白或血清维生素B12水平均无线性的相关性,血清维生素B12水平降低有助于诊断,但不是诊断SCD的必须条件；观察患者对维生素B12替代治疗的疗效,能帮助明确诊断；新的生化指标如血同型半胱氨酸及甲基丙二酸水平测定、脑脊液髓鞘碱性蛋白含量测定等有助于早期诊断SCD,神经电生理中诱发电位对SCD敏感性高,可发现早期病变和隐匿性病灶；脊髓MRI检查直观地显示病灶,主要表现为后索、侧索的长条状等T1长T2异常信号,胸髓多见,有助于SCD的诊断,特别对血清维生素B12水平正常的患者有确诊意义；脑脊液髓鞘碱性蛋白含量可反映SCD患者神经纤维髓鞘损害及修复程度。本病神经电生理及影像学检查、生化检测能客观地反应病变部位、性质及治疗前后的病情变化,因此对本病病变部位的判断、诊断、治疗前后病情变化的观察均很有价值,尤其对临床表现不典型的患者,在周围神经病和脊髓病两者之间关系完全不清楚的情况下,进行系统的电生理、影像学研究及生化检测很有必要。此外,对患者进行电生理、影像学方面的随访也是明确诊断、观察病情变化的重要手段之一。更多还原

【Abstract】 Subacute combined degeneration of the spinal cord(SCD)is a neurological degeneration disease due to vitamin B12 deficiency.It involves the posterior and lateral columns of the spinal cord, and sometimes the peripheral nerves. The typical clinical manifestation is deep sensation disorder in extremities or both lower extremities, sensory ataxia, spastic paralysis and peripheral neuropathy such as extremity numbness.Once the diagnosis of subacute combined degeneration of the spinal cord(SCD) depended on clinical manifestation and the measurement of serum level of vitamin B12.And it’s hard to make a final diagnosis to those patients with normal range of serum level of vitamin B12 or atypia clinical manifestation.It is the versatility and the non-specificity of clinical manifestation that makes the diagnosis difficult. Once be final diagnosed as SCD,the treatment is simple and effective.And in most of the time,a delayed diagnosis of SCD causes unreversible and fatal status.To make a summarize,we need to focus on making a early diagnosis,giving promptly treatment to avoid permanent nerve system disfunction. But more and more case reports in which the diagnosis had been delayed due to atypia clinical manifestation or the normal range of serum vitamin B12 cause physician to challenge the old diagnostic criteria.With the generally using of electrophysiology and magnetic resonance imaging in clinical,we have a deeper recognition in SCD which given us new sights about it. This review summarizing many literatures give a more detailed description about SCD aiming to elevate our recognition about this curable disease and help making early diagnosis.Conclusion:The SCD is not a rare clinical disease; There was no linear correlation between the severity of lesions in CNS and ferrohemoglobin level or level of serum VB12;A low serum vitamin B12 will assist us to make the diagnosis of SCD,but it is not essential; Observing the curative effect to vitamin B12 substitution treatment help us to comfirm the diagnosis; Electrophysiology,magnetic resonance imaging,new biochemical indicator such as serum homocysteic acid, the level of myelin basic protein(MBP) in cerebrospinal fluid(CSF) will assist in the early diagnosis of SCD. Evoked potential is critical for early diagnose and identification of silent cases of SCD; Lesions of SCD in spinal cord or brain can be objectively demonstrated in MRI mainly in posterior and lateral revealing columns.MRI clearly showed symmetrical iso-intense on T1 and hyper-intense on T2.Most lesions were seen at the thoracic cord. MRI help to make the diagnosis of SCD especially in those patients with normal range of serum vitamin B12. The level of MBP in CSF can reflect the severity of the lesion and prosthetic state of myelin sheath. According to many literatures, electrophysiology and magnetic resonance image can reveal the diseased region, reflect the nature and help us to observe the treatment effect. They have great value in helping making a diagnosis, revealing the diseased region and observing the treatment effect. It is essential to do electrophysiology and magnetic resonance image while you cannot tell the difference between peripheral nerve disease and myelopathy in patients with atypia clinical manifestation. Spinal cord MRI and EP could objectively show the lesions of SCD and the change before and after the treatment. These examinations and the follow-up of disease could be helpful in the diagnosis of SCD.更多还原