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Updated: Jul 8, 2026
06:01
Collecting Hair Samples for Hair Cortisol Analysis in African Americans
Published on: June 10, 2018
The hair collar sign.
Cathy A Stevens1, Wesley Galen
1Department of Pediatrics, T.C. Thompson Children's Hospital, University of Tennessee College of Medicine, Chattanooga, Tennessee 37403, USA. cathy.stevens@erlanger.org
American Journal of Medical Genetics. Part A
|January 19, 2008
Summary
Congenital scalp lesions with a hair collar may indicate underlying neural tissue. These cases show a significant risk of skull defects and central nervous system (CNS) anomalies, requiring careful evaluation.
Area of Science:
- Pediatric Dermatology
- Neurocutaneous Syndromes
- Congenital Malformations
Background:
- Hair collars are rare congenital scalp lesions.
- Often associated with heterotopic neural tissue.
- Typically located on the vertex or parietal scalp.
Observation:
- Two pediatric cases of congenital scalp lesions with hair collars were identified.
- A review of existing literature on hair collars was conducted.
- Most previously reported lesions were solitary and vertex/parietal.
Findings:
- Scalp lesions with hair collars are frequently composed of heterotopic neural tissue.
- A significant association exists between hair collars and skull defects.
- Central nervous system (CNS) and cerebrovascular anomalies are common comorbidities.
Implications:
- Early and thorough clinical assessment of hair collar lesions is crucial.
- Magnetic resonance imaging (MRI) of the brain is recommended before surgical intervention.
- Prompt diagnosis and management can mitigate risks associated with CNS and skull abnormalities.
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