Temporal Triangular Alopecia: What You Need to Know

Hair loss can be a distressing experience. Understanding specific causes and identifying the type of hair loss is essential to finding the right treatment.

Temporal Triangular Alopecia (TTA), also known as congenital triangular alopecia or Brauer nevus, is a rare condition that primarily affects children but can also be seen in adults. This article will provide an in-depth look at TTA, including its causes, symptoms, diagnosis, and treatment options, with a special focus on how hair transplantation can offer a viable solution.

What is Temporal Triangular Alopecia?

Temporal Triangular Alopecia is a non-scarring form of hair loss that typically presents as a well-defined, triangular or oval patch of hair loss in the temporal region of the scalp. The condition often appears in early childhood, usually between the ages of 2 and 6 years, but can also be noticed later in life. Unlike other forms of alopecia, TTA does not result in complete baldness; instead, the affected area typically contains fine, vellus hair (short, thin, light-colored hair) rather than normal, terminal hair¹. Both “vellus” and “terminal” hair types will be explained further below.

The hallmark of TTA is its stability—once the hair loss appears, it generally does not worsen or spread. The condition is usually unilateral, affecting only one side of the head, but bilateral cases (affecting both sides) have also been reported.

Terminal Hair Vs. Vellus Hair

Terminal hair and vellus hair are the two primary types of hair found on the human body, each serving distinct functions.

Terminal hair is thick, coarse, and pigmented, commonly found on the scalp, eyebrows, eyelashes, and other areas such as the beard, chest, and pubic region in adults. It typically grows longer and undergoes regular cycles of growth, resting, and shedding.

Vellus hair, on the other hand, is fine, short, and usually unpigmented, covering most of the body. It is often referred to as “peach fuzz” and serves as a protective layer, helping to regulate body temperature by providing insulation. Vellus hair can transition into terminal hair during puberty or due to hormonal changes, such as those seen in conditions like hirsutism (excess hair growth) or androgenetic alopecia. Understanding the differences between these two types of hair is crucial in fields like dermatology and hair restoration, as they play different roles in both aesthetics and health.

Causes of Temporal Triangular Alopecia

The exact cause of Temporal Triangular Alopecia is not well understood. However, it is generally believed to be a congenital condition, meaning it is present from birth, although it may not become apparent until later in childhood. Genetic factors are thought to play a role, but there is no clear inheritance pattern. Unlike other types of alopecia, TTA is not associated with autoimmune disorders or systemic diseases².

Explore our comprehensive blogs to learn about other types of hair loss and their unique characteristics:

Traction Alopecia: Hair loss caused by continuous pulling or tension on the hair, often due to tight hairstyles like braids or ponytails.
Androgenetic Alopecia: The most common form of hair loss, also known as male or female pattern baldness, influenced by genetics and hormones.
Alopecia Areata: An autoimmune disorder that leads to patchy hair loss, where the body’s immune system attacks hair follicles.
Alopecia Universalis: A more severe form of alopecia areata, resulting in complete hair loss on the scalp and body.
Telogen Effluvium: A temporary hair loss condition triggered by stress, illness, or hormonal changes, where a large number of hairs enter the shedding phase.

Symptoms and Clinical Presentation

The primary symptom of Temporal Triangular Alopecia is a distinct patch of hair loss in the temporal region, which is often triangular in shape but can also be oval. The affected area is typically smooth, with no signs of inflammation, redness, or scarring. Patients may notice fine, vellus hair within the bald patch, which distinguishes TTA from other forms of alopecia, such as alopecia areata, where the area may be completely bald².

TTA is usually asymptomatic, meaning it does not cause itching, pain, or discomfort. This type of hair loss condition is stable, meaning it does not typically progress or spread to other areas of the scalp.

Diagnosing Temporal Triangular Alopecia

Diagnosing TTA is primarily based on clinical observation. Dermatologists or hair specialists will examine the affected area, looking for the characteristic triangular or oval shape and the presence of fine, vellus hair. Trichoscopy using a polarized light handheld dermatoscope is a useful tool employed by dermatologists. A detailed medical history will also be taken to rule out other potential causes of hair loss¹.

In some cases, a scalp biopsy may be performed to confirm the diagnosis. The biopsy will typically show normal hair follicles with a reduced number of terminal hairs and an increased number of vellus hairs, without any signs of scarring or inflammation .

Treatment Options for Temporal Triangular Alopecia

While Temporal Triangular Alopecia is a benign condition that does not require medical treatment, those who are concerned about the cosmetic appearance of the hair loss may seek treatment options. Here are some of the most common approaches:

Observation: Since TTA is a stable and non-progressive condition, many individuals choose to monitor the area without pursuing treatment. This is especially true if the hair loss is not particularly noticeable or bothersome.

Topical Treatments: Some patients may try topical treatments, such as minoxidil, to stimulate hair growth. Minoxidil is a medication primarily used to treat high blood pressure. Interestingly, it was discovered that lower doses can stimulate hair growth³. This treatment works by prolonging the hair growth cycle and encourage new hair growth. Minoxidil foam (such as Regain®) is a commonly used topical form of the medication approved for treating both male and female pattern hair loss. Minoxidil comes as both an oral tablet and topical solution (applied to the skin). Minoxidil is more often used to treat androgenetic alopecia, and while they may be worth a trial, these treatments are generally not effective for TTA. This is because the condition is congenital, and the hair follicles in the affected area are not capable of producing terminal hair⁴.

Hair Transplantation: Hair transplantation is the most effective and permanent solution for restoring hair in affected areas of TTA. The procedure involves transplanting healthy hair follicles from a donor site, typically the back of the scalp, to the bald patch. Since TTA does not involve scarring and the underlying scalp remains healthy, the transplanted follicles can successfully grow and produce normal hair in the previously bald area. This procedure is often preferred by individuals concerned about the aesthetic impact of TTA, as it provides a long-lasting solution. Once the transplanted hair follicles establish themselves, they continue to grow just like in their original location, allowing patients to enjoy natural-looking results without the need for ongoing treatments⁵.

Cosmetic Camouflage: For those who prefer non-surgical options, cosmetic camouflage, such as hair fibres or scalp micropigmentation, can help make the bald patch less noticeable. Hair fibres are made from natural or synthetic keratin, the same protein that makes up human hair. They cling to existing hair through static electricity, giving the appearance of thicker, fuller hair. Hair fibres are easy to apply and can be used daily or as needed. They come in a variety of colours to match natural hair, making them a versatile option for both men and women. While hair fibres provide a quick and effective camouflage, they are a temporary solution and may need to be reapplied after washing or heavy sweating.

Scalp micropigmentation is a more permanent cosmetic camouflage technique that involves the application of tiny, colored pigments to the scalp, mimicking the appearance of natural hair follicles. This process creates the illusion of a fuller hairline or a shaved head look, making it an excellent option for those with more extensive hair loss or thinning. It is particularly beneficial for individuals who prefer a low-maintenance solution, as the results can last several years with minimal touch-ups. The procedure is non-invasive and does not require downtime, but it is important to choose a skilled practitioner to ensure natural-looking results.

When to Consult a Specialist

If you or your child has a patch of hair loss that you suspect might be Temporal Triangular Alopecia, it is important to consult with a dermatologist or hair loss specialist. While TTA is a benign and non-progressive condition, a professional evaluation is essential to confirm the diagnosis and discuss potential treatment options. Early consultation can also help differentiate TTA from other types of hair loss that might require different management strategies .

Conclusion

Temporal Triangular Alopecia is a unique form of hair loss that, while benign, can be a source of cosmetic concern for some individuals. Understanding the nature of TTA, including its causes, symptoms, and treatment options, is crucial for those affected by the condition. For those seeking a permanent solution, hair transplantation offers an effective way to restore hair in the affected area, providing natural-looking and lasting results. If you suspect you or your child may have TTA, consulting with a hair loss specialist can provide clarity and guide you towards the best treatment options for your needs.

References

Yin Li, V. C. and Yesudian, P. D. (2015) ‘Congenital Triangular Alopecia’, Int J Trichology, 7(2), pp. 48-53. Available at: https://ncbi.nlm.nih.gov/pmc/articles/PMC4502474/
Verma, P. (2016) ‘Triangular Temporal Alopecia Revisited’, Indian Journal of Dermatology, 61(1), 125. Available at: https://doi.org/10.4103/0019-5154.174179
Gilhar, A., Keren, A. and Paus, R. (2023) ‘Vellus-to-terminal Hair Follicle Reconversion Occurs in Male Pattern Balding and is Promoted by Minoxidil and Platelet-rich Plasma: In Vivo Evidence from a New Humanized Mouse Model of Androgenetic Alopecia’, Acta Derm Venereol, 103, adv12320. Available at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10599155/
Bang CY, Byun JW, Kang MJ, Yang BH, Song HJ, Shin J, Choi GS. (2013) ‘Successful treatment of temporal triangular alopecia with topical minoxidil’, Ann Dermatol, 25(3), pp. 387-8. Available at: Successful Treatment of Temporal Triangular Alopecia with Topical Minoxidil – PMC (nih.gov)
International Society of Hair Restoration Surgery. “Hair Transplantation: An Overview.” Available at: https://ishrs.org/