Kular Sam, Karsonovich Torin
Sheffield Teaching Hospitals NHS
Baylor College of Medicine
At the end of the 19th century, pathologists Julius Arnold (1835-1915) and Hans Chiari (1851-1916) were the first to describe the condition as a complex clinical and pathological condition involving cerebellar and brainstem deformities in children. Chiari malformations are defined as a spectrum of hindbrain abnormalities involving the cerebellum, brainstem, skull base, and cervical spinal cord. Different subtypes of Chiari malformations have been identified, based on the degree and contents of herniated tissue (see Chiari Malformation Types). Among the various types, the Chiari type 1 malformation is the most common subtype. Chiari 1 malformations are characterized by the caudal descent of the cerebellar tonsils through the foramen magnum of at least 5 millimeters. (see Chiari Malformation Types 1 and 2). Clinically, Chiari type 1 malformations may be asymptomatic or manifest from childhood to adulthood with tussive headaches, sleep disordered breathing, scoliosis, and focal neurological deficits. On the other hand, Chiari types 2, 3, and 4 are congenital and present much earlier in life than Chiari type 1 malformations.
Chiari畸形被定义为一系列涉及小脑、脑干、颅底和颈髓的后脑异常。根据椎管内移位的脑组织疝出类型以及脑或脊柱发育异常的特征，Chiari畸形已被分为4种类型。与基底凹陷一起，Chiari畸形是成人中最常见的颅颈交界区畸形。在19世纪末，病理学家朱利叶斯·阿诺德（1835 - 1915）和汉斯·Chiari（1851 - 1916）首次将这种情况描述为一种涉及儿童小脑和脑干畸形的复杂临床和病理状况。在Chiari畸形中，Chiari 1型畸形是较常见的变体。Chiari 1型畸形的特征是小脑扁桃体通过枕骨大孔向尾侧下移。然而，临床医生之间没有公认的通用定义，因为这种畸形在临床放射学相关性方面表现不一致。例如，一些作者最近提议将Chiari 1型畸形称为“Chiari综合征”，而“畸形”一词应保留用于2至3型。（见Chiari畸形1型和2型）。临床上，Chiari 1型畸形可以是无症状的后脑疝，也可以从儿童晚期到成年期表现为咳嗽性头痛和局灶性神经表现。另一方面，Chiari 2、3和4型是先天性的且具有临床意义。0型或0.5型Chiari畸形或无扁桃体疝的Chiari样症状、1型和2型之间的1.5型Chiari畸形以及复杂Chiari畸形的疾病分类搭配存在争议，未被普遍接受。（见Chiari畸形类型）
