That evening, my aunt called to say my little cousin had developed a "strange condition." A cord-like blue-black patch had appeared on the sclera of her left eye, accompanied by a dark spot beneath the left eye socket. Now, even her left temple and outer cheek were dotted with scattered black marks.A beautiful, adorable 10-year-old girl now had blemishes on her fair little face, severely affecting her appearance. More concerning was whether this might impact her vision. After an eye exam at the local hospital, the doctor only stated her vision was normal. Hearing my aunt's description, I had a preliminary idea but couldn't be entirely certain. So I offered some reassurance and asked her to send me photos of my cousin as soon as possible.
Though I'm often away, I've kept some awareness of my little cousin's condition. Since birth, she'd had a pea-sized blue-black spot on the sclera of her left eye, which went largely unnoticed over the years. My aunt mentioned that by age three, small dark spots began appearing under her eye sockets. Since they remained faint and caused no discomfort, no one bothered with this seemingly harmless "minor issue."
A few days later, the photos arrived, showing very typical symptoms. I called my aunt to explain that my little cousin had a pigmentary skin disorder—Nevus of Ota. I advised her to bring my cousin to the dermatology department at my hospital for a definitive diagnosis. If confirmed, laser treatment would be an option. As I suspected, it was indeed Nevus of Ota! Three days later, my little cousin received her first treatment at our hospital's dermatology department.Before and after the treatment, I briefly addressed their concerns.
So what exactly is Nevus of Ota? First described by Japanese dermatologist Masao Ota in 1938, it manifests as blue-brown macular lesions affecting the sclera and facial skin innervated by the trigeminal nerve. It is also known as the "superior palatine nevus."The exact cause remains unclear; some suggest it may be an autosomal dominant genetic trait, while others propose it could be a type of cutaneous hamartoma. Diagnosing Nevus of Ota is actually not difficult and can be based on the following points: 1. Approximately 50% of cases are congenital, commonly seen in children and adolescents. It may darken and expand during puberty, with a higher incidence in females than males.
2. They primarily occur in areas innervated by the first and second branches of the trigeminal nerve, occasionally involving the third branch region. This includes the upper and lower eyelids, temporal, and zygomatic areas, typically unilateral but occasionally bilateral.
3. Manifestations appear as brown, bluish-gray, blue, black, or purple macules, presenting as punctate, reticular, or map-like patterns. Occasional nodules may be present within the macules, ranging from several millimeters to several centimeters in size.
4. Most patients exhibit blue spots on the ipsilateral sclera.
5. Histopathological examination may reveal: dense clusters of rhomboid, dendritic, and stellate melanocytes aggregated between collagen fiber bundles in the upper reticular dermis, potentially extending into the papillary dermis or subcutaneous tissue.Many previously used treatments, such as dry ice compression, liquid nitrogen cryotherapy, and dermabrasion, can reduce pigmentation but rarely achieve complete cure. They often lead to scarring or hypopigmentation, are painful, and yield unsatisfactory results.Currently, laser therapy for Nevus of Ota commonly employs devices like the 755-nanometer emerald laser and the 694-nanometer ruby laser.
The treatment went smoothly, and everyone praised my little cousin for being so well-behaved and brave.After the treatment, my little cousin asked me, "Sis, will it leave a scar?" I gently stroked her head and explained that the laser wavelength used in this treatment is selective. This specific wavelength is absorbed by the melanocytes in the Nevus of Ota but not by other cells.Additionally, this laser operates in pulses—meaning after a period of laser exposure on the cells, there's an interval. This interval ensures the laser's heat affects only the melanocytes without transferring elsewhere, thus preventing scarring. "Will I need more treatments? Could it come back?" My little cousin, knowing this concerns her appearance, asked with particular care.
"After absorbing the laser energy, the melanocytes within the Nevus of Ota undergo thermal expansion and explode into countless tiny particles. These particles can be expelled from the body, with most being absorbed by phagocytes and then eliminated through the kidneys.This process of cells absorbing the pigment particles takes 2 to 3 months, so the next treatment should be scheduled 2 to 3 months later. Depending on the size of the area and the specific condition, generally 4 to 9 treatments are needed. After successful treatment, the skin color will be virtually identical to normal skin, leaving no scars. Currently, there is mild localized swelling on the face after treatment, which will subside within a few hours. The original dark pigmentation will begin to fade one month later and continue to lighten for another month."
Hearing this, both my aunt and little cousin breathed a long sigh of relief.