Arnold-Chiari malformation, sometimes referred to as 'Chiari malformation' or ACM, is a congenital anomaly of the brain in which the cerebellar tonsils are elongated and pushed down through the opening of the base of the skull (see foramen magnum), blocking the flow of cerebrospinal fluid (CSF). The brainstem, cranial nerves and the lower portion of the cerebellum may be stretched or compressed. Therefore, any of the functions controlled by these areas may be affected. The blockage of CSF flow may also cause a syrinx to form (syringomyelia). The following codes are used with International Statistical Classification of Diseases and Related Health Problems. ... The International Classification of Diseases for Oncology (ICD-O) is a domain specific extension of the International Statistical Classification of Diseases and Related Health Problems for tumor diseases. ... The following is a list of codes for International Statistical Classification of Diseases and Related Health Problems. ... The Mendelian Inheritance in Man project is a database that catalogues all the known diseases with a genetic component, and - when possible - links them to the relevant genes in the human genome. ... MedlinePlus (medlineplus. ... eMedicine is an online clinical medical knowledge base that was founded in 1996. ... The Diseases Database is a free website that provides information about the relationships between medical conditions, symptoms, and medications. ... Comparative brain sizes In animals, the brain, or encephalon (Greek for in the head), acts as the control center of the central nervous system. ... A hippopotamus skull A skull, or cranium, is a bony structure of Craniates which serves as the general framework for a head. ... In anatomy, the foramen magum is the large hole through the occipital bone in the base of the skull, through which the medulla oblongata (an extension of the spinal cord) exits the skull vault. ... Cerebrospinal fluid (CSF) is a clear bodily fluid that occupies the subarachnoid space in the brain (the space between the skull and the cerebral cortex—more specifically, between the arachnoid and pia layers of the meninges). ... The brain stem is the stalk of the brain below the cerebral hemispheres. ... Figure 1a: A human brain, with the cerebellum in purple. ... An uncollapsed syrinx (before surgery). ...

In infants, the most common symptoms are stridor and swallowing difficulties. In older children, upper limb weakness and breathing difficulties may occur. Patients may experience no symptoms or remain asymptomatic until early adulthood, at which point they will often experience severe headaches and neck pain. Fatigue, dizziness, vertigo, neuropathic pain, visual disturbances, difficulty swallowing, ringing in the ears, impaired fine motor skills, muscle weakness, and palpitations are other common symptoms. Because of the complex combination of symptoms and the lack of experience with ACM1 had by many, even outstanding neurologists and neurosurgeons, many patients are frequently misdiagnosed. A human infant The word infant derives from the Latin word in-fans, meaning unable to speak. It is commonly used as a slightly more formal word for baby (the youngest category of child). ... Stridor is a high pitched sound heard on inspiration that is indicative of airway obstruction. ...

Some patients may go an entire lifetime without having noticeable symptoms. Or, symptoms can be minimal, then turn severe suddenly due to head trauma which alters the condition of the spine, brain, or cerebellar tonsils and begins to cause more difficulties. Once these "onset of symptoms" occurs, the most frequent treatment is decompression surgery, in which a neurosurgeon seeks to open the base of the skull and through various methods unrestrict CSF flow to the spine.

Arnold-Chiari Malformation II occurs in almost all children born with both spina bifida and hydrocephalus, but ACM I is typically seen in children and adults without spina bifida. The scale of severity is rates I - IV, with IV being the most severe.

History

An Austrian pathologist, Professor Hans Chiari, first described these hindbrain malformations in the 1890s. A colleague of Professor Chiari, Dr. Arnold, later contributed to the definition of the condition, and students of Dr. Arnold suggested the term "Arnold-Chiari malformation" to henceforth refer to the condition. Pathology (in ancient Greek pathos = feeling, pain, suffering and logos = discourse or treatise, i. ... The 1890s were sometimes referred to as the Mauve Decade, because William Henry Perkins aniline dye allowed the widespread use of that colour in fashion, and also as the Gay Nineties, under the then-current usage of the word gay which referred simply to merriment and frivolity, with no...

External links

• World Arnold Chiari Malformation Association
• American Syringomyelia Alliance Project
• The Chiari Institute

• The Ann Conroy Trust (ACT)

 33 Southam Road Dunchurch, Rugby Warwickshire England CV22 6NL Tel: (+44)1788 537676 Fax: (+44)1788 569996 http://www.theannconroytrust.org.uk