DISCUSSION
Riehl melanosis is a condition of skin pigmentation characterized
by the sudden onset of gray-brown reticular
pigmentation. It has been attributed to a lichenoid reaction
or allergic contact dermatitis due to cosmetics or other allergens.
1-4 Reported therapies are few and rarely successful.
IPL therapy for this condition has been reported twice.6, 7 This
is the first report of the successful treatment using a Qs FD
Nd:YAG handpiece following recalcitrance to IPL treatment.
The theory of selective photothermolysis and patient response
guided the treatment of this patient. The Q-switching
mechanism of the device results in ultra-short, nanosecond
bursts of energy, which is preferentially absorbed by melanin
within the melanophages.8
The pathogenesis of Riehl melanosis is unknown. It has been
proposed that repeated episodes of subclinical inflammation,
from any number of etiologies, may result in the clinical
and histologic findings.3, 4 The dominant histological features
are basal liquefaction degeneration and papillary dermal
melanophages.4 The successful treatment of Riehl melano-
