Nevus of Ito
Nevus of Ito, known in full as nevus fusco-caeruleus acromiodeltoideus, is a benign congenital dermal pigmentation disorder. It appears as blue-gray, blue-brown or gray-black patches over the shoulder girdle, the acromion, the supraclavicular area, the upper chest and the shoulder blade. First described by Dr. Minor Ito in 1954, it is biologically identical to nevus of Ota; the key difference is which nerves supply the affected skin.
Like nevus of Ota, nevus of Ito is more common in people of Asian descent (especially women) and appears either shortly after birth or around puberty. At Haute-Derma, we treat nevus of Ito with a 1064 nm picosecond laser protocol that breaks up the deep dermal pigment cells without surgery, with a very low risk of scarring or recurrence.
Cellular Pathogenesis and Nerve Distribution
Nevus of Ito results from a disruption in the embryonic development of pigment cells:
- Arrested migration of melanoblasts: between weeks 8 and 10 of pregnancy, pigment precursor cells (melanoblasts) travel from the neural crest to the epidermis. In nevus of Ito, these cells stall and remain trapped in the deep dermis of skin supplied by the posterior supraclavicular nerve and the lateral cutaneous nerve of the arm.
- The Tyndall effect: because the dermal melanocytes sit deep among collagen bundles (150–400 µm below the basement membrane), shorter (blue) wavelengths of light are scattered more strongly as they pass through the skin, producing the typical blue-gray or gray-brown color.
- Changes in response to biological triggers: the melanosomes in nevus of Ito can darken with shifts in sex hormone levels (puberty, pregnancy) or with ultraviolet (UV) exposure.
Nevus of Ito vs. Other Dermal Pigmentation Disorders
| Nevus of Ito | Nevus of Ota | Mongolian Spot |
|---|---|---|
| Shoulder, acromion, shoulder blade, upper chest, neck (supraclavicular nerves) | One side of the face: eye, cheek, forehead, temple (trigeminal V1, V2) | Sacral and buttock area, lower back |
| Uniform blue-gray or blue-brown patches | Blue-gray patches, sometimes with blue spots on the sclera | Faint blue-gray patch with poorly defined edges |
| Permanent; does not fade on its own | Permanent; does not fade on its own | Usually fades and disappears by age 6–10 |
| Scattered spindle-shaped melanocytes in the dermis | Scattered spindle-shaped melanocytes in the dermis | Dermal melanocytes (deeper; regress on their own) |
Diagnosis and Clinical Screening at Haute-Derma
- Clinical Examination and Mapping the Affected Area
- Defining the borders and intensity of the pigmented band over the shoulder and neck.
- Checking whether nevus of Ito and nevus of Ota occur together in the same patient (this combination accounts for about 5–10% of congenital pigmentation cases).
- Dermoscopy and OCT Imaging
- Dermoscopy: fine granular or homogeneous blue-gray pigment within the dermis, with no surface scale or superficial vascular changes.
- Skin OCT imaging: pinpoints the depth of the dermal melanocytes so the laser penetration settings can be chosen accordingly.
- Screening for Malignant Change (Melanoma Screening)
- Although malignant transformation (dermal melanoma) of nevus of Ito is extremely rare (< 0.1%), any lesion that suddenly changes size, develops a raised nodule or ulcerates should be biopsied to rule it out.
Picosecond 1064 nm Laser Treatment at Haute-Derma
Because the pigment cells sit deep in the dermis, surface treatments such as chemical peels or creams do not work. The 1064 nm picosecond laser is currently the first-line option for removing nevus of Ito:
- Photoacoustic shockwave effect: the 1064 nm wavelength reaches the mid and deep dermis. Ultra-short pulses (< 450 picoseconds) deliver energy extremely quickly, creating a photoacoustic shockwave that shatters melanocytes and melanosomes into ultrafine particles.
- Natural clearance: the shattered pigment particles are engulfed by macrophages and gradually removed through the lymphatic system.
- Clinical Settings and Treatment Course:
- Spot size: a large spot (7–10 mm) ensures the energy penetrates deeply into the shoulder and neck skin.
- Fluence: adjusted between 2.5 and 4.0 J/cm² to achieve light frosting (a faint gray-white surface change) and mild redness.
- Treatment course: 5–8 sessions, spaced 8–12 weeks apart. These intervals are essential to give macrophages enough time to clear the fragmented melanin.
