Skin resurfacing with the erbium:YAG laser.

The Er:YAG laser provides superficial ablation and is generally used for more superficial rejuvenation. Three newer systems provide for thermal-coagulative and ablative properties. These systems are considered as intermediate resurfacing lasers, providing faster healing and results that are typically in between those of the CO2 and standard Er:YAG lasers. The use of traditional and combination Er:YAG lasers is reviewed along with preoperative and postoperative considerations.     

Mechanical effects of erbium:YAG laser bone ablation.

When intending to use pulsed erbium:YAG laser radiation for the ablation of small bones, e.g., the ossicular chain or footplate, not only temperature and thermal damage, but also mechanical side effects become important. In studies on desiccated bone the total recoil momentum caused by laser ablation was measured using a sensitive pendulum. The momentum depends linearly on the radiant energy of the laser pulse with a slope of 10(-4) kg m s-1/J. The temporal course of the recoil force during ablation observed by means of a piezoelectric transducer is nearly proportional to the laser pulse intensity. By evaluating recoil momentum and mass loss data, the average initial velocity of the plume was calculated to be 230 to 280 m s-1. The kinetic energy is approximately 1% of the input energy. The measurements support to the hypothesis of a thermally induced explosive process.     

Ab-interno neodymium:YAG versus erbium:YAG laser sclerostomies in a rabbit model.

This study was undertaken to determine whether thermally-induced tissue necrosis was a factor in ab-interno contact-laser sclerostomy failure. A rabbit model was used to compare the continuous-wave Neodymium (Nd):YAG with the pulsed Erbium (Er):YAG laser with respect to such failure. Laser energy was focused into a fused-silica fiber optic (400 microns) for the Nd:YAG laser (12 W; 3 to 5 seconds), and into a single-crystal, uncladded sapphire fiber optic (250 microns) for the Er:YAG laser (7 to 8 mJ; 250 microseconds; 6 to 8 pulses). The Nd:YAG and Er:YAG lasers required from 21 to 35 J and from 42 to 64 mJ, respectively, to create the sclerostomies. Filtering blebs and intraocular pressure reduction lasted longer (log-rank test; P less than .03) and surgical complications were fewer in the Er:YAG group than in the Nd:YAG group. By creating sclerostomies with minimal thermal damage, the Er:YAG laser may offer significant clinical advantages over lasers producing larger thermal effects.     

Xanthelasma palpebrarum: treatment with the erbium:YAG laser

BACKGROUND AND OBJECTIVE: Xanthelasma palpebrarum presents a therapeutic and aesthetic challenge because of its high visibility and frequent rate of recurrence with a wide variety of treatments. Many patients are disappointed by an initial unsuccessful treatment and fail to return for further therapy until the skin problem has become quite conspicuous. A simple treatment with few side effects and good acceptance remains an important goal. STUDY DESIGN/MATERIALS AND METHODS: Fifteen patients with a total of 33 xanthelasma lesions, were treated by an erbium:YAG laser. The follow-up period of observation was between seven and twelve months. RESULTS: All lesions were removed without hyperpigmentation or scarring. CONCLUSIONS: The erbium:YAG laser represents an effective means for treating xanthelasmas with few side effects.     

Post-operative healing of erbium YAG laser incisions

A pilot study was made on the post-operative healing of incisions in the tails of anaesthetized rats made by an erbium YAG laser. The incisions are compared with those made by a scalpel. Histological sections taken at intervals between 3 h and 14 days show little difference between the two methods of incision.     

Achieving superior resurfacing results with the erbium:YAG laser

Laser skin resurfacing has become increasingly popular. The carbon dioxide (CO2) laser seemingly remains the most commonly used laser modality for skin resurfacing. Many surgeons still promote the CO2 laser as being superior to the erbium:YAG laser, particularly for individuals with deeper lines. However, further experience with the erbium:YAG laser has shown the converse to be true. The erbium:YAG laser can be used to treat deep rhytids successfully, many times achieving results superior to those seen with the CO2 laser, particularly in the perioral region. The theory behind this relates to the 10-fold greater absorption of the erbium:YAG wavelength by water. The greater absorption produces more efficient vaporization, even at low fluences, with greatly reduced adjacent thermal injury. Ablation can be carried to deeper levels of the dermis than is consistently safe with the CO2 laser. Deliverance of total fluences in the range of 100 to 150 J/cm2, or more, produces a marked reduction or elimination of deeper rhytids. Clinically, experience with more than 300 cases indicates collagen remodeling occurs to a similar degree with the erbium:YAG laser as with the CO2 laser, as improvement in rhytids can be seen for 2 to 3 months after surgery. It would appear that superior results can be obtained without the "heat effect" of the CO2 laser. The erbium:YAG laser is capable of achieving superior resurfacing results, while offering many advantages to the patient, eg, reduced anesthetic requirements, shorter healing time, reduced erythema, less risk of pigmentary change, and more flexibility for resurfacing the skin off of the face.     

Collagen tightening induced by carbon dioxide laser versus erbium: YAG laser

BACKGROUND AND OBJECTIVE: Pulsed CO2 laser resurfacing improves photodamage and acne scarring by ablation of abnormal tissue with subsequent regeneration and remodeling of collagen and through heat induced collagen contraction. Whether collagen contraction persists long-term and helps maintain the skin tightening observed after resurfacing is debated. One possible mechanism of long-term clinical tightening is that of wound contracture that occurs as part of normal wound healing. If normal wound contracture, and not heat induced collagen contraction, is responsible for maintaining the initial skin tightening seen in CO2 laser resurfacing, then equal results would be expected from resurfacing with either CO2 or erbium lasers. The study was performed to determine whether there is a difference in skin tightening secondary to thermally mediated collagen contraction versus that which occurs secondary to tissue contraction of wound healing. The persistence of these changes over 6 months and the histologic characteristics were studied as well. STUDY DESIGN/MATERIALS AND METHODS: Nine patients had four tattoo dots applied to the upper eyelids, with horizontal axis measuring 18-20 mm and the vertical axis 6-10 mm. One month later, one eyelid was treated with three passes of the UltraPulse CO2 laser and the other eyelid with an erbium laser to the end point of early pinpoint bleeding. Three patients were treated with additional passes after pinpoint bleeding was encountered. The total number of pulses used per patient was recorded. Measurements of the vertical and horizontal distances were made after each pass and monthly for 6 months. The treated skin was then excised in performance of an upper lid blepharoplasty and the tissue submitted for histologic analysis. RESULTS: In the vertical plane, the UltraPulse CO2 laser induced an average of 43% tightening intraoperatively and this gradually diminished to an average of 34% by 6 months, whereas the wound contracture of erbium resurfacing was not seen until 1 month postoperatively, at which time 42% tightening was seen, gradually diminishing to 36% at 6 months. Three patients with erbium resurfacing had scarring present. These were the three patients treated most aggressively and also the three patients with the most significant wound contracture. Scarring was not seen on the CO2 treated side in any patients. In the horizontal plane, the CO2 laser caused 31% intraoperative tightening, decreasing to 19% at 6 months. In this plane, the erbium laser induced wound contracture was 12% at 1 month which remained stable and unchanged. CONCLUSIONS: Although wound contraction secondary to tissue healing may result in nearly the same tissue tightening as heat-induced collagen contraction, the two processes are very different and variable, with increased risk of scarring seen with wound contracture, compared with heat-induced collagen tightening. The tissue tightening seen with thermally induced collagen contraction is long-lasting, if not "permanent."     

Idiopathic isolated perioral hyperpigmentation and treatment with the erbium:YAG laser

Perioral hyperpigmentation is commonplace in practice; it can be a physiological finding or reflect a systemic life-threatening disease or syndromes, this is treated with different types of application. A 20-year-old female with isolated perioral hyperpigmentation and treatment of this lesion with an erbium:YAG laser is shown. There were no other signs and symptoms in this patient. Another pathological finding could not be determined during examinations, laboratory tests and radiological studies. The erbium:YAG laser was applied to the hyperpigmented area. There was no complication after laser application and an aesthetically successful result with patient satisfaction was achieved in both early and late terms. According to our knowledge this is the first report, which has described the isolated idiopathic type of perioral hyperpigmentation.     

Mid-infrared erbium:YAG laser ablation of bone: the effect of laser osteotomy on bone healing

A comparative study was undertaken in rabbit tibiae to assess the healing of bone in response to osteotomies by a mid-infrared erbium: YAG (2.94 microns) laser or a mechanical saw. Laser parameters necessary for osteotomy were shown to produce deep cuts with sharp edges and no gross charring or burning of adjacent bone. However, it was noted histologically that there was a delay in healing of the laser osteotomies as compared to saw osteotomies. This delay was caused by a microscopic zone of damage to bone adjacent to the laser cuts. It is concluded that, although the erbium: YAG laser may be a useful tool in orthopaedic surgery to ablate bone, under the conditions used in this study, there will be a delay in the healing process after laser osteotomy.     

Combined fractionated CO2 and low-power erbium:YAG laser treatments

This article addresses the use of fractionated CO(2) laser and erbium:YAG laser for facial rejuvenation. Outcomes and limitations of these techniques are discussed, along with a stepwise summary of techniques as they are used in clinical practice. An evaluation of patient satisfaction is presented for a group of patients who underwent combined fractional CO(2) and erbium:YAG facial resurfacing.     

Use of a dual-mode erbium:YAG laser for the surgical correction of rhinophyma

Rhinophyma is a cosmetically deforming disorder characterized by nodular hypertrophy of the nasal soft tissue. Treatment of rhinophyma usually consists of laser ablation or surgical excision for correction of the associated tissue deformity. We describe 6 patients with mild to severe rhinophyma who were treated with a dual-mode erbium:YAG (Er:YAG) laser, which provides the advantages of controlled ablative energy for tissue reduction and excellent intraoperative hemostasis. Outcome measures included patient satisfaction, clinician observer ratings, and an assessment of complications, including scarring, pigment abnormalities, and postoperative bleeding. All patients were satisfied with their outcomes, and no complications were detected during follow-up. All treatment outcomes were rated as very good to excellent at a 3-month follow-up visit. The flexibility of the dual-mode Er:YAG laser provides both controlled ablation and hemostasis, making it an ideal laser for the surgical treatment of rhinophyma.     

Side-firing germanium oxide optical fibers for use with erbium:YAG laser

BACKGROUND AND PURPOSE: During recent experimental studies, the erbium:YAG laser has been shown to be more efficient for lithotripsy and more precise for incision of soft urinary tissues than the conventional holmium:YAG laser. Mid-infrared optical fibers are being developed to allow endoscopic delivery of Er:YAG laser radiation. This paper describes the simple construction and characterization of a side-firing germanium oxide fiber for potential use with the Er:YAG laser in endourology. MATERIALS AND METHODS: The 450-microm-core side-firing fibers were constructed from germanium oxide fibers by polishing the distal tip at a 45 degrees angle and placing a protective quartz cap over the tip. The Er:YAG laser radiation, with a wavelength of 2.94 microm, was transmitted through the fibers. RESULTS AND CONCLUSION: The fiber transmission rate and damage threshold measured 48 +/- 4% and 149 +/- 37 mJ, respectively (n = 6 fibers). Sufficient pulse energies were transmitted through the side-firing fibers to produce contact tissue ablation.     

Ablation of bone and methacrylate by a prototype mid-infrared erbium:YAG laser

An erbium:YAG laser was used to generate 200-microseconds pulses of mid-infrared 2.94-microns light in both the single and multimode configurations. Laser pulses were focused on the surfaces of both rabbit long bones and methacrylate blocks, and the tissue response was examined histologically. The depth of thermal injury was determined by ocular micrometry. Over all energy levels tested, the erbium:YAG laser produced ablation of bone and methacrylate with minimal thermal damage to adjacent tissue. Increasing the laser energy per pulse produced increasingly wider and deeper grooves in both bone and methacrylate. However, such increase in laser energy produced a proportionately greater increase in the zone of thermal injury in methacrylate as compared with bone. These studies suggest the feasibility of a surgical erbium:YAG laser in orthopaedics and other forms of ablative surgery.