Melanie Grossman

Damage to hair follicles by normal-mode ruby laser pulses

BACKGROUND Although many temporary treatments exist for hirsutism and hypertrichosis, a practical and permanent hair removal treatment is needed. OBJECTIVE Our purpose was to study the use of normal-mode ruby laser pulses (694 nm, 270 microseconds, 6 mm beam diameter) for hair follicle destruction by selective photothermolysis. METHODS Histologically assessed damage in ex vivo black-haired dog skin after the use of different laser fluences was used to design a human study; 13 volunteers with brown or black hair were exposed to normal-mode ruby laser pulses at fluences of 30 to 60 J/cm2, delivered to both shaved and wax-epilated skin sites. An optical delivery device designed to maximize light delivery to the reticular dermis was used. Hair regrowth was assessed at 1, 3, and 6 months after exposure by counting terminal hairs. RESULTS Fluence-dependent selective thermal injury to follicles was observed histologically. There was a significant delay in hair growth in all subjects at all laser-treated sites compared with the unexposed shaven and epilated control sites. At 6 months, there was significant hair loss only in the areas shaved before treatment at the highest fluence. At 6 months, four subjects had less than 50% regrowth, two of whom showed no change between 3 and 6 months. Transient pigmentary changes were observed; there was no scarring. CONCLUSION Selective photothermolysis of hair follicles with the normal-mode ruby laser produces a growth delay consistent with induction of prolonged telogen with apparently permanent hair removal in some cases.

Long-term results after CO 2 laser skin resurfacing: a comparison of scanned and pulsed systems

BACKGROUND New laser technology permits the use of high-energy pulsed and continuous-wave carbon dioxide (CO2) lasers with flashscanners to treat rhytides. OBJECTIVE We compared the efficacy and side effects of the two leading CO2 lasers used in skin resurfacing. METHODS A total of 28 patients with facial rhytides were treated with either the UltraPulse or SilkTouch laser systems; in five additional patients, contralateral cosmetic units were treated with one system or the other in a direct comparison of the lasers. RESULTS We compared photographs taken before and after treatment, and a lessening of facial wrinkling was noted in all subjects. In some subjects improvement was confirmed by optical profilometry methods. Biopsy specimens in representative patients showed that immediate thermal damage was limited to 180 microns. Long-term postoperative specimens showed changes in the papillary dermis consistent with new collagen deposition and reduction of pretreatment solar elastosis. Posttreatment facial erythema was noted in half the patients for up to 2 months; transient hyperpigmentation was observed in one third of the treated areas. CONCLUSION Although the SilkTouch system produced more immediate thermal damage, there were no significant differences in efficacy or adverse effects between the lasers. Our results suggest that both laser systems, used with appropriate settings, are capable of safely smoothing the skin surface.

Chronic hyperkeratotic herpes zoster and human immunodeficiency virus infection

A patient with human immunodeficiency virus infection had hyperkeratotic papules in the T 11 and T 12 dermatomes in which she previously had papulovesicular herpes zoster. Findings of a biopsy specimen and viral culture of these papules subsequently revealed varicella-zoster that eventually responded to prolonged high-dose acyclovir therapy and debridement. A review of reported cases of hyperkeratotic varicella-zoster infections is presented, in addition to our recommendations for the treatment of varicella-zoster infection in patients who have acquired immunodeficiency syndrome.