Meningoencephalocele

Part of speech: noun

Definitions

1. A congenital defect characterized by the protrusion of the brain and its protective membranes through a skull opening ; a neural tube malformation involving both the meninges and brain tissue herniating externally ; a medical condition where the cranial bone fails to close, allowing brain and meningeal tissue to form a sac outside the head
2. An abnormal birth condition in which brain tissue and its covering membranes extend through a cranial bone gap ; a severe form of encephalocele including meninges alongside cerebral matter herniating beyond the skull ; a developmental anomaly causing a protrusive sac composed of brain and meninges through a skull defect
3. A rare neural tube defect marked by an external sac formed of meninges and brain matter due to an incomplete skull closure ; a malformation where both meninges and brain structures protrude through a cranial bone opening ; an embryological disorder leading to herniation of brain and meningeal layers through the cranium resulting in a visible outpouching

Etymology: This medical term is constructed from several Greek roots that describe a specific type of neural tube defect. It combines "meningo-", referring to the meninges, the protective membranes surrounding the brain and spinal cord; "encephalo-", derived from "enkephalos," meaning brain; and "-cele," meaning a swelling or hernia. Together, these elements depict a condition where both the meninges and brain tissue protrude through a defect in the skull. The formation of such compound words became common in medical terminology during the 19th and early 20th centuries when physicians and anatomists sought precise terms to classify various congenital malformations. The roots themselves trace back to ancient Greek, but their combination into a term describing this specific pathology is more modern, reflecting advances in neurology and embryology. This term is part of a broader family of words ending in "-cele," used to denote herniations or protrusions—such as "meningocele" (meninges only) and "encephalocele" (brain tissue only). The prefixing of both "meningo" and "encephalo" indicates that the hernia involves multiple layers, emphasizing the complexity of the condition. Its use in English medical literature likely dates from the early to mid-20th century, coinciding with improved diagnostic techniques. By building this compound, medical professionals could communicate the precise nature of the defect without ambiguity, reflecting a systematic approach to naming diseases that combines classical languages with modern clinical knowledge.

Synonyms: brain meningocele, encephalomeningocele