Erbium: YAG laser

Fang, J.Y., et al. 2004. Enhancement of topical 5-aminolaevulinic acid delivery by erbium YAG laser and microdermabrasion A comparison with iontophoresis and electroporation. Br J Dermatol 151 132. 

Lee, W.R., et al. 2001. Transdermal dmg delivery enhanced and controlled by erbium YAG laser A comparative study of lipophilic and hydrophilic drugs. J Control Release 75 155. 

Quiroz-Mercado H, Sanchez-Buenfil E, Guerro-Naranjo JL, et al. Successful erbium YAG laser-induced chorioretinal venous anastomosis for the management of ischemic central retinal vein occlusion. A report of two cases. Graefes Arch Clin Exp Ophthalmol 2001 239 872-875. 

Maes K.E. and Sherk H.H. 1994. Bone and meniscal ablation using the erbium YAG laser. Lasers Surg. Med. (Suppl.) 6 31. 

Manaloto RM, Alster T (1999) Erbium YAG laser resurfacing for refractory melasma. Dermatol Suig 25 121-123... 

A particularly efficient cw vibronic laser is the emerald laser (BeaAliSiaOigtCr " ). When pumped by a 3.6-W krypton laser at Xp = 641 nm, it reaches an output power of up to 1.6 W and can be tuned between 720 and 842nm [5.131]. The slope efficiency dPout/dPin reaches 64% The erbium YAG laser, tunable around X = 2.8 p.m, has found a wide application range in medical physics. 

The studies employed both erbium YAG and pulsed CO2 surgical lasers [Figure 6(a)] to resurface established vesicant bums under general anaesthesia at between three and four days post-exposure. Sulphur mustard bums treated by pulsed CO2 laser debridement showed a threefold increase in healing rate compared to controls (untreated) at two weeks post exposure (p = 0.061) [Figure 6(b)]. This increase was achieved with only partial removal of necrotic tissue and may be due to disruption of the eschar... 

Despite all the technological applications and investigations of rare-earth YAG lasers, the optical spectra of some of the rare-earth ions in this host are of questionable quality and in some cases nonexistent. Only two rare-earth ions in YAG, neodymium and erbium, have been thoroughly investigated and reported. This is rather surprising when compared to lanthanum trifluoride (LaFa), for which Kaminskii reports only 16 lasers, although abundant excellent data exist (Camall et al., 1977) for all of the rare-earth ions in LaFs except terbium. 

Hill R.A., Le M.T., Yashiro H. et al. 1993. Ab-interno erbium (Er YAG) laser sclerostomy with iridotomy in Dutch cross rabbits. Lasers Surg. Med. 13 559. 

Comparing the QS laser with the long-pulsed 532-nm Nd YAG laser in the treatment of melasma, the latter produced less PIH because it lacks the photomechanical effects of the QS laser [126]. QS alexandrite laser or PLDL combined with 15-25% TCA peel and/or Jessner s solution was shown to be effective, safe, and relatively inexpensive treatment modalities in the recalcitrant pigmentary disorders [92]. Combination of QS alexandrite and ultrapulse CO lasers yielded statistically significant result in improving refractory melasma compared to QS alexandrite laser alone [5]. Erbium YAG used on patients with skin phototypes II-V may have demonstrated improvement but transient PIH developed 3-6 weeks after laser treatment [100]. 

Other YAG lasers have been constructed where ytterbium, erbium, thulium, or holmium is used instead of neodymium. 

In the NIR side, the best lanthanides are 5dterbium, erbium, and neodymium (it is used in the Nd YAG laser, see Section 3.1.5). Holmium is less investigated but shows a very interesting emission spectrum with a red peak and an NIR peak. 

CW 1617 nm emission with a slope eflflciency of 51.7 % has been observed in a 0.5 at.% Er YAG ceramic laser [184]. Eflflcient operation of the high-power erbium-doped polycrystalline Er YAG ceramic laser was resonantly pumped by using a high-power 1532-nm Er,Yb fiber laser. Lasing characteristics of Er YAG ceramics with different Er " concentrations were evaluated and compared. With an OC of 15 % transmission, the 0.5 at.% Er -doped YAG ceramic laser generated 14 W of output power at 1617 nm for 28.8 W of incident pump power at 1532 nm. 

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