Quantitative near infrared spectroscopic analysis of Q‐Switched Nd:YAG treatment of generalized argyria

Abstract

Background and Objective Generalized argyria is a blue-gray hyperpigmentation of the skin resulting from ingestion or application of silver compounds, such as silver colloid. Case reports have noted improvement after Q-Switched Neodymium--Yttrium Aluminum Garnet laser (1064nm QS Nd:YAG) laser treatment to small surface areas. No reports have objectively monitored laser treatment of generalized argyria over large areas of skin, nor have long-term outcomes been evaluated. Study Design/Materials and Methods An incremental treatment plan was developed for a subject suffering from argyria. A quantitative near infrared spectroscopic measurement technique was employed to non-invasively analyze tissue-pigment characteristics pre- and post-laser treatment. Post-treatment measurements were collected at weeks 1, 2, 3, and 4, and again at 1 year. Results Immediate apparent removal of pigment was observed with 1 Q-switched 1064 nm Nd:YAG laser treatment (3-6 mm spot; 0.8-2 J/cm2) per area. Entire face, neck, upper chest and arms were treated over multiple sessions. Treatments were very painful and general anesthesia was utilized in order to treat large areas. Near-infrared spectroscopy was used to characterize and quantify the concentration of silver particles in the dermis based on the absorption features of the silver particles as well as the optical scattering effects they impart. We were able to estimate that there was, on average, 0.042 mg/mL concentration of silver prior to treatment and that these levels went below the minimum detectable limit of the instrument post-treatment. There was no recurrence of discoloration over the 1-year study period. Conclusion QS 1064 nm laser treatment of argyria is a viable method to restore normal skin pigmentation with no evidence of recurrence over study period. Quantitative spectroscopic measurements, 1) confirmed dyspigmentation was due to silver, 2) validated our clinical assessment of no recurrence up to one year post-treatment and 3) indicated no collateral tissue damage with treatments.

Acitretin in dermatology

“…Presumably the action is attributed to the immunomodulator properties of acitretin on Langerhan cells. [50] In a questionnaire-based retrospective cross-sectional survey by Gruber et al conducted on 30 patients of Pachyonychia congenita the efficacy and side effects of oral retinoids (10-50 mg/day for 1-240 months) were assessed. [51] Overall, 30 patients were treated of which 12 patients received acitretin and 14 received isotretinoin.…”

Blue skin

“…Attempts at treating argyria with chelation, dermabrasion, and hydroquinone have been ineffective . Several case reports have shown laser therapy to be effective at treating argyria using a Q‐switched 1064 nm Nd:YAG laser . Additionally, due to the pathophysiologic mechanism of dyspigmentation in argyria, sun protection is recommended to prevent discoloration …”

Use of fine needle aspirate from peripheral nerves of pure-neural leprosy for cytology and PCR to confirm the diagnosis: A pilot study

“…Recently, Q-switched 1064-nm neodymium-doped yttrium aluminium garnet laser has been reported to be useful for resolving the skin discoloration in argyria. [42,47,50,54] Indian perspective All the four cases of argyria, described in this article are due to intake of silver coated betel nut/cardamoms [ Table 1]. An extensive literature search conducted with the purpose to identify the reports of argyria pertaining to related forms of exposure yielded five citations.…”