This paper gives an overview of ectopic brain tissue, extracranial brain tissue that is not directly connected to the brain itself.
The paper shows that extracranial brain tissue that is not directly connected to the brain itself may be an isolated cutaneious embryonic defect. It discusses how these are usually located on the occipital or parietal areas of the scalp and are often called heteropic brain tissue or cutaneous ectopic brain (CEB). Most of the time these are simple defective tissue that can easily be removed from the scalp. However, there are several different types of ectopic brain tissues and some of these can be signs of underlying central nervous system problems. The paper discusses several cases where the importance of getting a thorough evaluation of the tissue is shown.
Table of Contents:
Definition of Cutaneous Ectopic or Heterotopic Brain Tissue
Summary of Four Patients with Scalp Nodules Surrounded by Hair Collars In the Study by Drolet and Clowry
History of CEB
The Hair Collar Sign: Marker for Cranial Dysraphism
Why the “Hair Collar”
Ectopic Brain as Orbital and Conjunctival Mass
Heterotopic Brain and Meningeal Tissue
Information about Heterotopic and Ectopic Brain Tissue
Table of Contents:
Definition of Cutaneous Ectopic or Heterotopic Brain Tissue
Summary of Four Patients with Scalp Nodules Surrounded by Hair Collars In the Study by Drolet and Clowry
History of CEB
The Hair Collar Sign: Marker for Cranial Dysraphism
Why the “Hair Collar”
Ectopic Brain as Orbital and Conjunctival Mass
Heterotopic Brain and Meningeal Tissue
Information about Heterotopic and Ectopic Brain Tissue
“Perhaps the question can be asked why the researchers termed the phrase, “hair collar”. Why is there a hypertropic ring of long hair that surrounds these lesions? If these were examined, the hair follicles would be found to increase in number and many of these will be quite large. In fact, the angle that each hair follicle exits the skin does not fall randomly, but are located at precise directions that the hair follicles take.
” The hair pattern is thought to be dictated by differential shearing forces and the point of maximal tension, the vertex, is where the parietal scalp whorl is commonly found. Perhaps at some point early in development, encephaloceles and meningoceles produce aberrant shearing forces during the formation of the follicles forcing them to point outward, away from the defect” (Drolet and Lawrence 309).