In short. Trichoscopy is an examination of the scalp and hair under high magnification with a dermatoscope or a video camera. The procedure is painless, takes 15–30 minutes and involves no punctures. It shows hair density, differences in shaft thickness, the condition of follicular openings and vessels. From these signs a trichologist distinguishes androgenetic alopecia from telogen effluvium, alopecia areata or scarring forms.
A patient arrives with one complaint, “my hair is falling out”, and the description of symptoms often ends there. The scalp looks calm from the outside, and the loss is visible only on the pillow and in the shower drain. There can be at least a dozen causes, and each one requires different treatment. That is why a naked-eye examination is rarely used in trichology as a standalone method.
Trichoscopy closed that gap. The term became established in dermatological literature in the late 2000s, and today the method belongs to the standard diagnostic algorithm for hair loss. It reveals what remains invisible without magnification: miniaturised hairs, empty follicular openings, perifollicular inflammation.
Below we explain how the examination proceeds, what the doctor looks for on the screen and why a trichoscopy report often changes the treatment plan.
What trichoscopy is and why it beats a simple examination
Trichoscopy is dermoscopy of the scalp. The doctor places an optical device on the skin that magnifies from ×10 with a handheld dermatoscope up to ×70 and more with a video dermatoscope displaying the image on a monitor. Some systems allow far greater magnification, but for routine diagnosis of alopecia moderate values are enough.
The first advantage of the method is that it is non-invasive. To confirm scarring alopecia or tell complex inflammatory conditions apart, doctors previously had to perform a scalp biopsy fairly often. Trichoscopy has substantially reduced the need for that procedure, although it has not eliminated it entirely. A review in the Journal of the American Academy of Dermatology describes trichoscopy as the core tool of the second stage of assessment in a patient with hair loss, right after history taking and the pull test.
The second advantage is documentation. Images are stored in the chart, and after 3–6 months the doctor compares the same area at the same magnification instead of relying on a subjective impression that it “seems denser now”.
The third advantage is speed. Results are discussed immediately, during the same trichologist consultation, with no waiting for a laboratory.
Who is referred for trichoscopy
There are no formal restrictions: the method is safe at any age and during pregnancy. In practice it is performed when the diagnosis raises a specific question.
- Increased shedding: daily loss consistently exceeds the normal amount of hair loss per day for longer than 6–8 weeks.
- Thinning without clear patches: the parting has widened and the scalp shows through the hair.
- Patchy loss: smooth round areas without hair.
- Scalp complaints: itching, flaking or tenderness together with shedding.
- Treatment monitoring: assessment of the effect of minoxidil, finasteride or device-based procedures after 3–6 months.
- Transplant planning: evaluation of the donor area and of the activity of the underlying disease.
If you are unsure whether it is already time to see a doctor, use the early signs of balding as a guide: a widening parting, a receding frontal hairline, thinning of the temporal and frontal zones.
How trichoscopy works: step by step
The examination is built into the consultation and is usually not perceived by the patient as a separate procedure.
- History: the doctor clarifies when the shedding started, how quickly it progressed, whether you had childbirth, surgery, illnesses with high fever or rapid weight loss, which medications you take and whether baldness runs in your family.
- Examination and pull test: the doctor gently pulls a strand of 50–60 hairs. If more than 6–10 shafts remain in the hand, the test is considered positive.
- Scanning the zones: the dermatoscope is applied to at least four areas – frontal, vertex, occipital and temporal. The occiput matters as a control: in androgenetic alopecia it stays relatively preserved.
- Capturing images: photographs are saved with a reference to the zone and the magnification used.
- Measurement: the software or the doctor counts hairs per square centimetre, the share of thin shafts and the number of hairs per follicular unit.
- Discussion: the doctor shows the images on the screen and explains exactly what is visible in each zone.
How long it takes and whether it hurts
Scanning takes 10–20 minutes, and the whole consultation lasts about an hour. There is no pain: the device only touches the skin through a transparent glass plate. Sometimes an immersion fluid or gel is used to remove glare. Part of the zones are then examined dry, because fluid smooths the scales and hides flaking.
What the doctor sees on the screen
The trichoscopic picture consists of four groups of signs: the hairs themselves, follicular openings, vessels and interfollicular skin. The diagnosis rests not on a single finding, but on their combination and on the zone where they dominate.
Markers that most often decide the diagnosis
- Hair diameter diversity: more than a fifth of the shafts in the field of view are visibly thinner than the rest. This is the main trichoscopic marker of androgenetic alopecia.
- Perifollicular pigmentation: a brownish halo around the opening, a sign of early miniaturisation.
- Yellow dots: dilated openings filled with keratin and sebum; typical of alopecia areata.
- Black dots and exclamation mark hairs: shafts broken near the surface, a sign of active alopecia areata.
- Short vertical hairs of uniform thickness: regrowth after telogen effluvium, a favourable sign.
- Absence of follicular openings: the key sign of a scarring process, when the follicle has already been replaced by connective tissue.
A systematic approach to this terminology is proposed in an updated review with a diagnostic algorithm: the authors advise reading trichoscopy step by step, against a fixed list of parameters, rather than hunting for one “recognisable” sign.
Trichoscopy and phototrichogram: what is the difference
These two studies are often confused. Trichoscopy is a static examination: it shows how the hair looks right now. A phototrichogram is a dynamic test: hair is trimmed short over a small area of about 1 cm², an image is taken, and after 48–72 hours the same zone is photographed again.
The growth in length shows which hairs are growing (anagen phase) and which stand still (telogen phase). Normally the share of anagen hairs on the scalp is roughly 80–90%, and telogen hairs make up to 15–20%. The average growth rate is about 0.3 mm per day.
The third method is a scalp biopsy. It is ordered rarely: when trichoscopy shows signs of a scarring or atypical inflammatory process and histological confirmation is needed.
| Parameter | Trichoscopy | Phototrichogram | Biopsy |
|---|---|---|---|
| What it assesses | Hair structure, follicular openings, vessels, skin condition | Anagen to telogen ratio and growth rate | Follicle structure at tissue level |
| Invasiveness | None | Minimal, a small area has to be trimmed | Removal of a skin fragment under local anaesthesia |
| Number of visits | One | Two, 48–72 hours apart | One plus waiting for histology |
| When it fits | Initial diagnosis of any hair loss | Quantitative assessment and treatment monitoring | Suspected scarring or rare alopecia |
| When results arrive | Immediately during the consultation | After the second visit | Within 1–3 weeks |
How to prepare for the examination
- Do not wash your hair for 1–2 days: fresh washing removes flaking and changes the picture of the skin.
- Skip styling products: hairsprays, dry shampoos and volumising powders create artefacts on the images.
- Do not colour your hair for 2–4 weeks: pigment distorts the assessment of shaft thickness and colour.
- Come with your hair loose: tight ponytails, extensions and hairpieces should be removed in advance.
- Bring your test results: ferritin, complete blood count, TSH, vitamin D, if you had them done within the last 6 months.
- Make a list of medications: hormonal contraception, retinoids, antidepressants and anticoagulants affect the hair cycle.
Blood tests do not replace trichoscopy, and the reverse is equally true. For example, iron and vitamin deficiency is visible only in blood, while shaft miniaturisation shows up only under magnification. Quite often the cause is combined, and without both studies the treatment plan stays incomplete.
What the report contains and what to do next
A trichoscopy report is not a diagnosis in itself, but a structured description of findings. A typical protocol includes the following items.
- Hair density by zone, in hairs per cm². The approximate range for the scalp is 200–300, but the figure depends noticeably on hair type and ethnicity.
- Share of thin (miniaturised) shafts as a percentage.
- Number of hairs per follicular unit: normally units of 2–3 hairs prevail, while in androgenetic alopecia the share of single-hair units grows.
- Condition of follicular openings: preserved, empty or absent.
- Signs of inflammation: redness, flaking, perifollicular changes.
- Comparison with the occipital zone as an internal control.
The doctor then matches the picture with your history and the stage on the Norwood-Hamilton scale or the Ludwig scale and builds a plan. This may be topical therapy, systemic drugs, device-based procedures or observation with a repeat examination after 3–6 months. Repeat trichoscopy remains the only way to see objectively whether treatment works, because the subjective feeling of density changes along with your haircut and the lighting.
Trichoscopy before a hair transplant
For the surgeon this examination answers three questions.
- Is the process stable. If shedding is active and uncontrolled, the transplanted grafts will survive, but your own surrounding hair will keep thinning. The result will look uneven within a year.
- What resource the donor area holds. The doctor counts density on the occiput and temples and assesses the share of miniaturised hairs. If signs of miniaturisation appear in the donor area too, graft planning changes.
- Are there any contraindications. Scarring alopecia in an active phase, an untreated fungal infection or marked inflammation are a reason to treat first rather than operate.
That is why trichoscopy is performed even for those who came specifically for a hair transplant, even when the patient feels certain about the diagnosis. The general principles of assessment in hair loss are also described by the American Academy of Dermatology: examination under magnification, supplemented when needed by blood tests or a biopsy.
Frequently asked questions
Does trichoscopy hurt?+
No. The device only touches the skin through a transparent glass plate, with no punctures or injections. Sometimes the doctor applies a few drops of immersion fluid or gel to remove glare. The examination suits children, pregnant women and patients for whom a biopsy is contraindicated.
How long does the examination take?+
Scanning the zones itself takes 10–20 minutes. Together with history taking, the pull test and an explanation of the results, the consultation lasts about an hour. The findings are discussed immediately, with no need to wait for a laboratory.
Do I need to shave my head before trichoscopy?+
For standard trichoscopy nothing needs to be shaved. Trimming a small area of about 1 cm² is required only for a phototrichogram, and the doctor warns you about it in advance. The zone is chosen so that the surrounding hair covers it.
How often should trichoscopy be repeated?+
During active treatment a follow-up examination is usually done after 3–6 months: earlier than that, changes do not yet show up on the images. The doctor then sets the interval depending on the diagnosis and the dynamics, most often once every six months or once a year.
Can trichoscopy be done during pregnancy?+
Yes. The method is non-invasive, with no radiation and no medications, so there are no restrictions for pregnant or breastfeeding women. It is one of the few ways to investigate postpartum hair loss without additional interventions.
How does trichoscopy differ from a trichogram?+
A trichogram involves plucking a bundle of hair and examining the roots under a microscope, so it is painful and produces errors because the shafts get damaged. Trichoscopy assesses hair in place, without plucking, and in modern practice it has almost entirely replaced the trichogram.
Does trichoscopy replace blood tests?+
No, these studies complement each other. Trichoscopy shows what is happening to the follicles, but it does not explain systemic causes. Iron deficiency, thyroid dysfunction or a hormonal imbalance are visible only in tests, so in diffuse hair loss both are ordered.