A non healing ulcer on scalp.

Angiosarcoma is a soft tissue tumour with a dismal prognosis. We present a 74 year old male presenting with a non healing ulcer on the scalp. On histopathology a diagnosis of angiosarcoma was made. An early diagnosis and tumour size play a pivotal role in the survival of the patient.

Diagnostic utility of dermatoscopy in hydroquinone-induced exogenous ochronosis.

BACKGROUND: Hydroquinone is the preferred topical bleaching agent used in the treatment of melasma. The adverse effects of its chronic use are confetti-like depigmentation and exogenous ochronosis. Exogenous ochronosis manifests clinically with gray-brown or blue-black hyperpigmentation, as well as pinpoint hyperchromic caviar-like papules over the malar region. Dermatoscopic findings of ochronosis are unique and point towards a clue for its diagnosis. METHODS: Three cases of suspected hydroquinone-induced exogenous ochronosis while treating melasma were subjected to dermatoscopy and histopathology studies. RESULTS: Dermatoscopy in the areas of caviar-like hyperpigmentation revealed accentuation of the normal pseudo-rete of the facial skin with amorphous densely-pigmented structures obliterating some follicular opening and multiple thin, short arciform structures. On histopathological examination, curved ochre-colored structures, 'banana-shaped' fibers, were seen in the dermis of all patients. CONCLUSION: Exogenous ochronosis is difficult to treat. Dermatologists should be able to differentiate it from melasma and immediately discontinue hydroquinone. Exogenous ochronosis has characteristic features on dermatoscopy which may obviate the need for an invasive procedure of biopsy for its diagnosis.

Triads in dermatology.

It is imperative for any dermatology resident to have a good knowledge of the various triads in dermatology. For an easy grasp over this topic, we have grouped the various triads on the basis of their etiologies.

Trigeminal trophic syndrome: a rare entity.

Trigeminal trophic syndrome is a rare condition resulting from self-manipulation of the skin after a peripheral or central injury to the trigeminal system. The syndrome consists of a classic triad of anaesthesia, paraesthesia, and a secondary persistent or recurrent facial ulceration. We describe a 60 year-old woman who developed this syndrome as a sequel to the gasserian ganglion block for trigeminal neuralgia. She had also developed melasma within 1 year. A remarkable benefit was achieved by proper patient education and topical antibiotics which led to the healing of all ulcerations within 4 weeks. In the case reported here, the diagnosis of the trigeminal trophic syndrome was made primarily as a result of the physician's experience with the syndrome previously.