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Nevus of Ota: morphological patterns and distribution in 47 Yemeni cases
M Alshami1, M A Bawazir, A A Atwan
1Department of Dermatology, Kuwait University Hospital, Sana'a University, Sana'a, Yemen.
Background:
Nevus of Ota is a rare pigmentary disorder characterized by melanocytic hamartoma of the skin along the distribution of trigeminal nerve branches.
Aim:
To study the morphological features of nevus of Ota, and their relation with facial regions and trigeminal branches areas.
Methods:
Patients with nevus of Ota who attended Kuwait University Hospital dermatology clinic and a private dermatology clinic in Sana'a, Yemen, between January 2008 and December 2010, were clinically evaluated. The morphology of nevus of Ota was classified to homogenous, speckled or mixed. The distribution of the lesions was assessed based on both facial regions and areas supplied by the trigeminal nerve.
Results:
Forty-seven patients with nevus of Ota (F = 38, M = 9) were evaluated. Eighty percent of patients were females. Mixed (homogenous and speckled) appearance was seen in 47% of all patients. Periocular region was the most commonly affected facial region (67%), and the maxillary area was the most commonly involved trigeminal branch area (94%). Forty-seven percent of cases had scleral pigmentation. Interesting features of nevus of Ota involving the nasal septum and crossing the midline of the face were noted.
Conclusions:
To the best of our knowledge, this is the first study that examines the distribution and morphology of nevus of Ota in Middle Eastern population. Including the morphological appearance of the nevus is practical and more clinically descriptive, and therefore should be integrated in the classification in future studies.
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