The subarachnoid space is a vital area located between the arachnoid membrane and pia mater that plays a critical role in cushioning and protecting the brain and spinal cord. To spell "subarachnoid space," one can use the International Phonetic Alphabet (IPA) phonetic transcription system which represents each sound in a word with a symbol. In IPA, "sub" would be transcribed as /sʌb/, "arachnoid" as /əˈræknɔɪd/, and "space" as /speɪs/. Understanding phonetic transcription can help ensure accurate spelling and pronunciation of complex medical terms.
The subarachnoid space is a term used in neuroanatomy to describe a specific region within the central nervous system. It is a narrow, fluid-filled cavity that exists between the arachnoid membrane and the pia mater, which are two of the three layers that make up the meninges – the protective covering of the brain and spinal cord.
This space is located just beneath the arachnoid mater, which is the middle layer of the meninges. It is filled with cerebrospinal fluid (CSF), a clear and colorless liquid that surrounds and cushions the brain and spinal cord, acting as a shock absorber. The subarachnoid space is continuous throughout the entire central nervous system, extending from the brain down to the end of the spinal cord.
The subarachnoid space plays a crucial role in the circulation of cerebrospinal fluid. It contains numerous blood vessels that supply nutrients and oxygen to the brain and spinal cord. Moreover, it acts as a conduit for the drainage of waste products and excess CSF, allowing it to be reabsorbed into the bloodstream. This fluid exchange system helps to maintain the balance and pressure within the central nervous system.
Medical conditions such as subarachnoid hemorrhage, which is bleeding into the subarachnoid space, or inflammation of the meninges, known as meningitis, may affect the normal functioning of this space and can have serious implications for the health of the individual.
Cavum subarachnoidale, the space between the pia mater and the arachnoid in which is the cerebrospinal fluid and, at the termination of the spinal cord, the nerves forming the cauda equina.
A practical medical dictionary. By Stedman, Thomas Lathrop. Published 1920.
The word "subarachnoid" is derived from the combination of two Latin roots: "sub" meaning under or beneath, and "arachnoid" derived from "arachne" which means spider. The arachnoid is one of the three membranes that cover the brain and spinal cord, resembling a spider web. The space between the arachnoid and the innermost membrane, the pia mater, is known as the subarachnoid space. Consequently, the term "subarachnoid space" refers to the area situated beneath the arachnoid membrane.