Anatomy of the Hair

The anatomy of the human hair follicle is much more complex than the average person imagines.  The follicle can be separated into 3 main regions: the lower segment (bulb and suprabulb), the middle segment (isthmus), and the upper segment (infundibulum). All of which are important to the overall health and growth of our hair.

*insert image of hair follicles

Hair Follicle Life Cycle

The 3 stages of the hair follicle life cycle can be separated into: anagen, catagen, and telogen. Each stage has a specific role during the rest and growth period of the hair follicles. The anagen stage is the “active growth” period (2-6 months) during the hair follicle life cycle. The catagen stage is the follicular transition stage which is the shortest of the 3 stages lasting roughly 1-2 weeks. Finally, the hair follicle enters the telogen phase (2-4 months) which is also known as the resting phase. Ultimately the hair follicle breaks off and returns to the anagen phase.

*insert image of hair follicle life cycle*

 

Hair Miniaturization

Some patients deal with hair loss miniaturization, which is where hairs become shorter over a specific period of time. During miniaturization, the body secretes a hormone called dihydrotestosterone inducing the hair follicle to shrink.

 

The individual hairs produced by these follicles are unable to grow to full size due to this shorter growth window and so they decrease in size (diameter and length) over time until they eventually disappear. This process of “miniaturization” is the main mechanism in androgenetic alopecia (genetic balding).

 

Hair Evaluation

Hair evaluations can be utilized using one of the three main methods:

  • Non-invasive methods (questionnaire, standardized wash test, daily hair counts, 60-s hair count, trichoscopy, contrasting felt examination)
  • semi-invasive methods (trichogram and unit area trichogram)
  • invasive methods (scalp biopsy).

 

The 60-Second Hair Count Technique

Materials required:

  • One clean hair comb
  • One clean pillowcase or sheet*
  • One timer/smartphone
  • One journal/notepad and pen (for recording)

Directions:

  1. Begin the 60 Second Hair Count test before your typical shampoo/shower routine. Dry scalp hair counts will generate the most accurate outcome.
  2. Lay out a clean pillowcase or sheet on a flat surface. *The sheet or pillowcase should be a color that is contrasting to your hair color. For instance, blonde, red, gray hairs appear best against a dark color sheet, while darker hair colors appear best against a white/light color sheet.
  3. Leaning over the pillow case or sheet, comb your hair beginning at the back of the scalp and stroking forward towards the front of your scalp. Time this with a timer or smartphone for 60 seconds.
  4. Count the number of hairs that fall onto the pillowcase/sheet as well as the hairs that stuck in the comb. Record your number. Clean out the comb.
  5. Repeat the 60 Second Hair Count Test before your next 2 shampooings, using the same clean comb and a clean,contrasting-colored pillow case or sheet. In the end, you should have 3 recordings for 3 icount tests performed before 3 consecutive shampooings. If you shampoo your hair every other day, perform the test every other day, right before shampooing.
  6. Perform and record the 60-Second Hair Count Test for 3 consecutive shampooings on a monthly basis. Report your findings to your plastics surgeon.

 

Interpreting Your Results:

Your 60-second hair count recordings are both a useful and standardized method in helping your physician determine is your hair loss is normal or abnormal. It is normal to lose roughly 100 strands per day, but if you are losing significantly more than 100 hairs per day, your hair may require further examination. A microscopic examination will be able to help you determine your scalp’s follicular makeup and determine any potential abnormalities of the hair shaft and bulb. Hair appearance abnormalities can help to clearly distinguish different types of hair loss such as telogen effluvium, anagen effluvium, and active diffuse alopecia areata.