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At least 253 records · Page 14Linked to original sources

Laser lithotripsy of difficult bile duct stones by means of a rhodamine-6G laser and an integrated automatic stone-tissue detection system.

This report describes the initial clinical implementation of a new laser lithotripter system capable of effective fragmentation of common bile duct stones with a high degree of safety provided by an integrated stone-tissue detection system. This system automatically terminates laser pulse transmission if tissue contact is sensed. Eighteen patients with giant or impacted common bile duct stones refractory to standard treatment techniques were treated via the endoscopic retrograde route using a rhodamine-6G dye laser with an integrated stone-tissue detection system. In the event of tissue contact, the stone-tissue detection system cuts off the laser pulse after 190 ns (after transmission of 5% to 8% of the total pulse energy). Nine patients were treated under cholangioscopic control, and nine patients were treated blindly under fluoroscopic control using only standard duodenoscopes with either a 6F standard endoscopic retrograde cholangiopancreatography catheter (4 patients), a 6.8F balloon catheter (3 patients), or a laser lithotriptor basket (2 patients). Laser-induced fragmentation was achieved in all 18 patients (100%). Sixteen of 18 patients (89%) became completely stone-free after completion of the treatment, including additional intracorporeal shock wave lithotripsy in five patients. The only major complications occurred in one fully anticoagulated patient with a prosthetic heart valve who developed significant hemobilia and transient cholangitis but recovered after conservative treatment. Laser lithotripsy using the rhodamine-6G dye laser plus stone-tissue detection system appears safe and effective and allows "blind" fragmentation of difficult common bile duct stones to be performed under radiologic control.

Adult↗

Evaluation of functional defects in branch retinal vein occlusion before and after laser treatment with scanning laser perimetry.

OBJECTIVE: This study was aimed at localizing and quantifying retinal defects in patients with branch retinal vein occlusion by means of scanning laser perimetry and analyzing the mechanism involved in the functional recovery after laser therapy. DESIGN: Prospective nonrandomized clinical trial with concurrent comparison group. PARTICIPANTS: Fifty-eight patients with isolated branch retinal vein occlusion. Thirty-nine eyes received laser treatment; 19 eyes were observed without treatment. INTERVENTION: Argon laser photocoagulation was performed according to the Branch Vein Occlusion Study recommendations. MAIN OUTCOME MEASURES: Retinal functional deficits were evaluated with scanning laser perimetry and fluorescein angiography first at baseline, at 3-month follow-up visits and 3 months after laser treatment. RESULTS: After laser treatment, the scotoma encroached on foveal fixation in 31% of eyes, remained stable in 36%, and regressed from the foveal avascular zone in 33%. Improvement in vision was correlated with increasing scotoma distance from fixation. Total scotoma size increased in 50% of eyes after treatment. Depth of scotoma and degree of angiographic leakage showed no direct correlation. CONCLUSIONS: Stabilization and increase in visual acuity after laser treatment did not correlate with an overall decrease in scotoma size. Improved central visual function seen in 25% of treated eyes appeared to be due to withdrawal of scotoma from the fovea.

Adult↗

Errors in laser spot size in laser trabeculoplasty.

By microscopic examination of 50-micron laser burns made on orange paper at different eye-piece settings of the slit-lamp microscope, 27 commercial argon lasers were evaluated for accuracy of 50-micron spot size and for coincidence of the aerial focal points of the laser and the microscope. Only four lasers (14%) produced a spot less than 70 microns diameter (double the area of a 50-micron spot) with the eye-pieces set on zero. With the eye-pieces focussed for minimum spot size, 12 lasers (44%) still gave a minimum spot of 70 microns or more, and four of those gave a spot of 100 microns or more. Improperly focussed lasers and oversize laser spots are a major problem in laser trabeculoplasty.

Humans↗

Clinical analysis of the neodymium:YLF picosecond laser as a microkeratome for laser in situ keratomileusis. Partially Sighted Eye Study.

PURPOSE: To evaluate the use of a picosecond neodymium:YLF (Nd:YLF) laser as a nonmechanical intrastromal microkeratome. SETTING: Universita Cattolica del Sacro Cuore, Rome, Italy. METHODS: An intrastromal spiral disc pattern of picosecond laser pulses was used to create a corneal flap for laser in situ keratomileusis (LASIK) in 14 partially sighted eyes. RESULTS: Flaps with a 6.0 mm diameter and 180 to 200 microns depth were successfully created in most cases. The underlying stroma was treated with a Lambda Physik excimer laser using a 3.5 to 4.5 mm optical zone. Patients were divided into 3 groups for target corrections of 5.0, 10.0, and 15.0 diopters of myopia. Good corneal clarity and refractive undercorrection were recorded in each group 6 months postoperatively. The undercorrection was due in part to the limited optical zone of the laser's delivery system. Some flap decentration was noted. CONCLUSION: This pilot study indicates that the Nd:YLF picosecond laser may be clinically applied for creating corneal flaps for LASIK. Further refinements of the laser delivery system will include enlargement of the flap diameter and improvements in flap centration. The use of a femtosecond laser may expand the capabilities and precision of this technology.

Adult↗

Laser-assisted hair transplantation: histologic comparison between CO2 and Ho:YAG lasers.

BACKGROUND: Various laser wavelengths and devices have been advocated for use in the creation of recipient channels during hair transplant surgery, including flash-scanned CO2, Ho:YAG (lambda = 2.12 microm), and Er:YAG (lambda = 2.94 microm). OBJECTIVE: To determine the tissue injury caused by flash-scanned CO2 and pulsed Ho:YAG lasers during the creation of hair transplant recipient channels and to assess the efficacy of the Ho:YAG laser. METHODS: Recipient channels were created in vivo in human scalp tissue using both lasers, and were excised and prepared for histologic examination. Optical micrometry of tissue sections was used to assess thermal injury. RESULTS: The Ho:YAG laser created jagged, irregular-shaped channels with larger zones of thermal injury (superficial deepithelialization, thermal necrosis, and thermal damage). In contrast, the CO2 laser produced well-defined cylindrically shaped channels free of cellular debris with minimal epithelial disruption and significantly less lateral thermal injury. CONCLUSION: Given that the Ho:YAG produced larger regions of thermal injury and recipient channels that were unacceptable for graft, the CO2 laser remains the better choice for the creation of recipient channels during hair transplant surgery. However, ongoing research will be necessary to determine the optimal laser wavelength and/or devices for this procedure.

Carbon Dioxide↗

Nonablative laser skin resurfacing using a 1540 nm erbium glass laser: a clinical and histologic analysis.

BACKGROUND: A variety of laser systems have recently become available that allow for selective dermal remodeling without disruption of the epidermal surface. Modest clinical improvement in mild to moderate photoinduced facial rhytides with minimal morbidity is typical of these nonablative lasers, providing a significant advantage over traditional ablative laser systems. OBJECTIVE: To determine the clinical and histologic effects of a novel 1540 nm erbium glass laser on facial rhytides. METHODS: Patients with mild to moderate periorbital and perioral rhytides received a series of three monthly treatments with a 1540-nm erbium-doped phosphate glass laser by a single operator. Photographic and clinical evaluations were independently conducted by the patient and a masked medical observer at each treatment visit and at 1, 3, and 6 months following the final treatment session. Skin biopsies were obtained for histologic analysis by a board-certified dermatopathologist at baseline, immediately following laser irradiation, and at one and six months post-treatment. RESULTS: Slow, progressive clinical improvement of rhytides was noted in all patients after each treatment and continued throughout the extended follow-up period. Side effects of treatment were limited to transient erythema and edema immediately following laser irradiation. No serious adverse effects were noted. Histologic skin changes were not apparent until several months following treatment, when an increase in dermal collagen was noted. CONCLUSIONS: The nonablative 1540 nm erbium glass laser system with contact cooling produces gradual clinical and histologic improvement in mild to moderate facial rhytides with minimal risk of serious adverse sequelae.

Adult↗

[Laser-induced thermotherapy (LITT). Use of round and pointed laser applicator systems--initial results].

PURPOSE: To assess the advantages and disadvantages by using round and sharp laser application systems during laser-induced thermotherapy. METHOD: 6 in vitro examinations were performed and 12 patients with liver metastases of colorectal carcinoma were treated with laser-induced thermotherapy. All lesions were closely localised to the diaphragm, liver capsule and large intrahepatic vessels. Five patients were treated with the sharp and 7 patients with the round applicator system. After CT-guided insertion of the catheter system into the metastasis laser therapy was performed under MRI control (approx. 25 W, 20 min). RESULTS: Reduction of the distance between the laser applicator and rounded laser catheter tipp (approx. 0.5-1 cm) leads to better placement of the laser applicator in metastases located near the diaphragm, liver capsule and large intrahepatic vessels. Improved therapy results due to complete ablation of metastases were obtained. All patients treated with the round system had complete ablation of metastasis. In 3 of 5 patients treated with the sharp system, MRI control 2 days after therapy showed a residual tumour margin close to the diaphragm or to an intrahepatic vessel. DISCUSSION: Improved ablation can be obtained by closer placement of a round laser catheter in liver metastasis located near the diaphragm, liver capsule and large intrahepatic vessels.

Adult↗

Arterial laser welding with a 1.9 micrometer Raman-shifted laser.

A new 1.9 micron Raman-shifted neodymium:yttrium aluminum garnet (Nd:YAG) laser was used for small vessel welding. Bursting pressures and stresses of sutured and laser-welded arteriotomies created in the rat femoral artery and aorta were measured. Sutured arteriotomies had a significantly higher burst stress than laser-welded arteriotomies. Although there were no significant differences in burst stress at the various laser powers tested, an optimal power was identified. The laser was also used to weld transected rat aortas. The average power delivered was 200 mW for 30 seconds per anastomosis. The average time for completing an anastomosis was 6 minutes compared with 18 minutes when sutures were used. In relation to proximal aortic diameter, there was a 7.9% decrease at the anastomosis immediately (n = 4), and a 6.6% and 4.9% increase occurred at 24 hours (n = 4) and 10 weeks (n = 5), respectively. Acute anastomotic compliance, and compliance at 24 hours and 10 weeks were decreased by 47.2%, 39.5%, and 47.8%, respectively, and were similar to sutured anastomoses. Histology showed little thermal denaturation of the aorta within 0.6 mm of the anastomosis, approximately 1 mm of medial cell death, and nearly normal elastic fiber alignment. One focal false aneurysm was noted at 10 weeks. Although the sutured and laser-welded anastomoses share similar compliance changes, the laser-welded anastomoses are more isodiametric. This preliminary experience with the 1.9 micron laser shows the distinct advantages of a handheld fiber, no requirement for cooling irrigation, speed, and no difference in compliance from sutured anastomoses.

Analysis of Variance↗

A preliminary clinical and histopathological study of laser skin resurfacing using a frequency-doubled Nd:YAG laser after application of Chromofilm.

BACKGROUND AND OBJECTIVES: Carbon dioxide (CO2) and Er:YAG lasers are commonly used for laser skin resurfacing. In demonstrating their efficacy, intra- and interoperator variability may be important. In attempting to solve this problem, a new concept was developed which combines a previous application of an exogenous chromophore onto the skin in a standardized way (Chromofilm) and irradiation with a millisecond, low-power pulsed laser. MATERIALS AND METHODS: This study aimed to evaluate this new concept in vivo in human skin using a 532-nm Nd:YAG laser connected to a scanner using the following parameters: 532 nm, 2W, 1-mm spot size, 30-mm2 hexagonal surface irradiation and 50-120-ms pulse duration. The laser irradiation was performed both 15 h and 1 h prior to the facelift procedure. Tissue samples were examined histologically to determine the injury depth using nitroblue-tetrazolium chloride (NBTC) staining, haematoxylin-eosin staining and Masson's staining. RESULTS: Morphometric analysis of histological preparations showed that the depth of injury was dose-dependent: 50-ms pulse duration induced total epidermis ablation and fine dermal coagulation; 120-ms pulse duration induced dermal coagulation down to 120 microns. No residual carbon film was observed on histologic sections. CONCLUSION: Laser skin resurfacing using a 532-nm laser irradiation after application of a carbon film transfer is an effective method for skin resurfacing. With this new galenic approach (Chromofilm), the control of all parameters (thickness, chromophore concentration and distribution) can be achieved to predict the thermal injury obtained after laser irradiation.

Burns↗

Systemic toxicology and laser safety of laser targeted angiography with heat sensitive liposomes.

Angiography is currently limited by its lack of local and tissue specificity. The dye rapidly fills both the retinal and choroidal vessels and leaks out of the vessels thus hampering visualization of small vascular beds such as occult choroidal neovascularization. We have developed a method of laser targeted delivery based on encapsulating the dye in heat sensitive liposomes, administering the liposomes intravenously and causing them to release their content by noninvasively warming the target tissue with a laser pulse delivered through the pupil. The local release yields a bright fluorescent bolus which selectively highlights retinal or choroidal vessels. A preliminary investigation of the potential side effects of the method is presented. In rats the systemic toxicity of carboxyfluorescein-entrapped liposomes was compared with that of the free dye. No significant difference was found between the two. Non-human primates exposed to repeated laser targeted angiography were monitored over time and no significant side effects were observed. The safety of the laser exposures was assessed by conventional fluorescein angiography and histopathology. Choroidal laser targeted angiography was achieved without damage. Retinal laser targeted angiography was accompanied by mild and local damage in an area remote from the fovea. The study indicates that laser targeted choroidal angiography can be performed safely and holds promise for diseases such as age related macular degeneration with occult choroidal neovascularization. Further improvements are needed to ensure that no side effects accompany retinal laser targeted angiography.

Animals↗

Laser stapedotomy minus prosthesis (laser STAMP): absence of refixation.

OBJECTIVE: To determine what percentage of patients with otosclerosis could successfully undergo a laser stapedotomy minus prosthesis over a 5-year period, and to determine the percentage of patients in whom refixation develops during follow-up. STUDY DESIGN: Retrospective case review of 136 patients (137 ears) who underwent primary surgery for otosclerosis. SETTING: An otology/neurotology tertiary referral center. PATIENTS: Patients were chosen if they had clinical evidence of otosclerosis without a history of otologic surgery. INTERVENTIONS: A standard stapes approach was used for all patients. For the laser stapedotomy minus prosthesis, a hand-held laser probe was used to vaporize the anterior crus of the stapes and perform a linear stapedotomy across the anterior one third of the footplate. If otosclerosis was confined to the fissula ante fenestram, the stapes became completely mobile. The stapedotomy opening was sealed with an adipose tissue graft from the ear lobe. MAIN OUTCOME MEASURES: Pure-tone audiometry with appropriate masking and auditory discrimination testing was performed before surgery, 6 weeks after surgery, and every year thereafter. RESULTS: Of the 137 cases, favorable anatomy and minimal otosclerosis allowed 46 (33.6%) of these patients to undergo laser stapedotomy minus prosthesis. Fifty-seven patients (41.6%) could not undergo the procedure because of extensive otosclerosis. The remaining 34 patients (24.8%) did not receive laser stapedotomy minus prosthesis because of other anatomic or technical difficulties. Of the 34 patients in the laser stapedotomy minus prosthesis group with more than 4 months follow-up, the average air-bone gap was closed from a mean of 22 dB (SD 10 dB) to 6 dB (SD 4 dB) 6 weeks postoperatively. Follow-up periods ranged from 5 months to 53 months (mean 767 days, SD 437 days). The long-term air-bone gap improved slightly to an average of 5 dB (SD 6 dB) in comparison with the sixth postoperative week value. CONCLUSION: Laser stapedotomy minus prosthesis is a minimally invasive procedure, which over the follow-up period has a very low incidence of refixation, as evidenced by a lack of progressive conductive hearing loss. The success of this procedure depends on the correct selection of cases. This procedure has been successfully performed on 33.6% of patients undergoing primary stapes surgery. Laser stapedotomy minus prosthesis seems to be a viable alternative to conventional stapedotomy that yields good results without evidence of refixation over an extended time.

Adipose Tissue↗

Hearing outcome of laser stapedotomy minus prosthesis (STAMP) versus conventional laser stapedotomy.

OBJECTIVE: The objective of this study was to compare short-and long-term hearing outcomes for patients undergoing primary laser stapedotomy minus prosthesis (STAMP) versus conventional laser stapedotomy. STUDY DESIGN: We conducted a retrospective case review of 167 consecutive patients from 1993 to 2002. SETTING: Otology/neurotology tertiary referral center. PATIENTS: We studied those with clinical otosclerosis without previous otologic surgery. INTERVENTIONS: Patients with otosclerosis confined to the fissula ante fenestram underwent STAMP. Patients with more extensive otosclerosis or anatomic contraindications to STAMP underwent standard laser stapedotomy. MAIN OUTCOME MEASURES: Pure-tone audiometry was performed before surgery, postoperatively, and on routine follow-up examination. RESULTS: Of the 183 ears in 167 patients, 128 (67.1%) underwent laser stapedotomy and 55 (32.98%) underwent STAMP. The STAMP mean air-bone gap (ABG) closed from a preoperative value of 22 dB (standard deviation [SD], 10 dB) to 6 dB (SD, 7 dB) on average follow up of 778 days. In 128 laser stapedotomy patients with an average follow up of 747 days, the preoperative mean ABG closed from 27 dB (SD, 10 dB) to 8 dB (SD, 7 dB). There was a trend toward improvement in high-frequency air conduction thresholds after STAMP versus worsening of high-frequency thresholds in the conventional stapedotomy group. There was a statistically significant improvement in most recent postoperative high-frequency (6000-8000 Hz) air conduction thresholds in the STAMP patients compared with patients who underwent conventional laser stapedotomy. CONCLUSION: Laser STAMP, when used for isolated anterior footplate otosclerosis, provides excellent high-frequency hearing, yields lasting results similar to conventional laser stapedotomy, and has a low incidence of refixation necessitating revision surgery.

Adolescent↗

Coronary laser thermal angioplasty in the swine: reduced complications with shorter laser delivery time.

Although laser thermal angioplasty (LTA) with a laser heated metal probe has been tolerated in diseased human coronary arteries, definition of a safety threshold is lacking. Determination of safer operation parameters for coronary LTA using a new "over the wire" 1.3-mm laser probe catheter was attempted in seven normal pigs in which platelets were labeled with indium-111. Argon laser power of 10 watts was used for 1, 2, 3, and 5 seconds. Macroscopic findings, platelet deposition and histologic changes were compared between the laser treated coronary segments and controls, the nonheated laser probe, and the wire alone segments. After 1-second LTA, there was no vessel perforation or occlusive thrombi and only infrequent nonocclusive thrombi; platelet deposition was minimal; and histologic alterations rare and superficial. These findings were comparable to controls, the nonheated laser probe, and the wire alone segments. In contrast, vessels treated for 2, 3, and 5 seconds had more frequent perforation, and occlusive and nonocclusive thrombi that was accompanied by platelet deposition significantly greater than vessels treated with LTA for 1 second. A deep histologic injury was present in most of these segments. Additionally, the safety of laser delivery of 1 second repeated for five times was tested in two additional pigs. On macroscopic and histologic analysis the incidence of vessel perforation, occlusive and nonocclusive thrombi appeared slightly less when compared to the 2-, 3-, and 5-second LTA groups, and more than the 1-second LTA group.(ABSTRACT TRUNCATED AT 250 WORDS)

Angioplasty, Laser↗

The synergistic effects of rhodamine-123 and merocyanine-540 laser dyes on human tumor cell lines: a new approach to laser phototherapy.

Many new photosensitizers and laser wavelengths are being tested to improve photodynamic therapy by enhancing specific tumor uptake and/or retention, lowering systemic toxicity, and increasing laser tissue penetration. In this study the potential synergistic effects of rhodamine-123 (Rh-123) and merocyanine-540 (MC-540) sensitization of human tumor cell lines after laser exposure were explored. In a first series of experiments, the kinetics of uptake of Rh-123 and M-540 were tested on three human leukemia cell lines (K562, RAJI, 729HF2), P3 squamous carcinoma, and M26 melanoma. Our results demonstrate a clear difference in the rate and amount of uptake of MC-540 (K562 > P3 > RAJI > 729HF2 > M26) and Rh-123 (P3 > RAJI > 729HF2 > K562 > M26) by these cell lines. In a second series of experiments, M26 tumor cells were sensitized with either Rh-123 (1 microgram/ml) or with MC-540 (20 micrograms/ml) alone or with a combination of the two dyes for 60 minutes, then exposed to the argon (514.5 nm) laser at nonthermal energy levels. Our results demonstrate a significant enhancement of the tumoricidal effects of the laser on M26 carcinoma cells after sensitization with both dyes together (MC-540 and Rh-123) when compared to each dye alone. As with combination antibiotherapy, the synergistic effects of two laser dyes that have different intracellular targeting sites appear to enhance tumoricidal effects significantly after exposure to a matching laser wavelength. The data provide evidence for effective laser phototherapy by dye synergy.

Antimetabolites, Antineoplastic↗

Argon laser phototherapy of human malignancies using rhodamine-123 as a new laser dye: the intracellular role of oxygen.

Recent studies demonstrated that the cationic, mitochondrial-specific dye Rhodamine-123 (Rh-123), is an efficient tumor photosensitizer for Argon laser treatment of human cancer cells both in vitro and in tumors grown as xenografts in athymic mice. To demonstrate the photodynamic mechanism of action of this reaction, the intracellular role of oxygen and temperature changes in treated cells have to be defined. In the current study, a large panel of human tumor cell lines of diverse histologic origin were tested for in vitro sensitivity to Rh-123 and the Argon laser (514.5 nm) in oxygen, deuterium oxide (D2O), and nitrogen (N2) environment. Tumor cells in suspension were first sensitized to Rh-123 (1 or 20 micrograms/ml for 1 hour), cooled on ice to 4 degrees C, and then exposed to the Argon laser (delta T = 14 +/- 1 degree C). Cell proliferation measured by [3H]-thymidine uptake 24 hours after sensitization with Rh-123 and laser treatment was significantly decreased in tumor cells kept in oxygen and D2O atmospheres. No decrease in DNA synthesis was seen in Rh-123 and laser treated cells kept in an N2 environment. Control tumor cells treated with Rh-123 or the Argon laser separately did not show any decreased [3H]-thymidine uptake in oxygen, D2O or N2 environment. These results provide evidence of a photodynamic process since Rh-123 sensitization and Argon laser activation occur at nonthermal levels of energy and are oxygen dependent. The high effectiveness of this technique of photodynamic therapy with the Argon laser, and low toxicity of Rh-123 could make its clinical use very attractive for the treatment of superficial malignancies.

Deuterium↗

Nd: YAG interstitial laser phototherapy guided by magnetic resonance imaging in an ex vivo model: dosimetry of laser-MR-tissue interaction.

Interstitial laser phototherapy (ILP) is a promising technique in which laser energy is delivered percutaneously to various depths of tumors. This technique will become clinically useful only when efficient, sensitive, and noninvasive monitoring systems are developed. In this study, the spatial distribution of ILP in bovine liver tissue, induced by a Nd: YAG laser with an interstitial sapphire-frosted contact probe, was evaluated by magnetic resonance imaging (MRI). Tissue was exposed to three energy densities of the Nd:YAG laser by a reproducible method of dosimetry. Thermal profiles were measured with a probe inserted 5 mm from the laser tip. T1-weighted magnetic resonance images were taken after the laser exposure. Tissue specimens were then evaluated for standard quantification of laser-induced damages. A linear correlation between the level of laser energy, induced temperature change, lesion size on T1 magnetic resonance image, and volume of histological damage was observed. Further improvement of this technique of dosimetry in an in vivo model should allow the development of software for MRI which will correlate the above parameters and render this technique of ILP clinically useful.

Animals↗

[Does the light of soft lasers or of combination soft and middle-power lasers improve wound healing in rats? Continuing studies].

In recent years, soft and middle-power lasers have been employed in the treatment of wounds and various dermatoses, but as yet no experimental confirmation of their effects has come available. However, we have been able to show in a recent study that light from combined soft and middle-power lasers applied on postoperative days 1, 2, 3, 5 and 8 has a positive effect on wound healing in rats. The present study was intended to clarify the influence of the type of laser light and treatment duration under controlled conditions. In 24 rats, a 3-cm incision was made in the abdominal wall and sutured with 5 single knots. Eight of the animals served as controls, while the remaining animals were treated with laser light, 8 with a soft laser for 10 min/day on postoperative days 2, 3, 5, 8 and 15, the other 8 for 20 min. on day 1 only with combined soft and middle-power lasers. The wounds were photographed on post-operative days 1, 2, 3, 5, 8 and 15. 10 independent observers rated the photographs on a scale of 1 to 4 on the basis of edge approximation and absence of inflammation. Soft laser light alone did not improve wound healing as judged by these criteria. Nor did a single dose of combined soft and middle-power laser light have any statistically significant effect.

Animals↗

Clinical effect of the copper vapour laser compared to previously used argon laser on cutaneous vascular lesions.

The copper vapour laser has in theory qualities which make it interesting in the treatment of cutaneous vascular malformations. In order to study the clinical effect of the copper vapour laser and to compare its effect with the effect of the argon laser, we treated 38 patients with port-wine stain or facial telangiectasia with the copper vapour laser. Thirty-one patients were evaluated and of these 24 were improved or much improved. Nineteen patients had previously been treated with the argon laser, and in this group the copper vapour laser had better effect than the argon laser in 8 patients and equal effect in 9 patients. In 7 patients side-effects like scarring or hyperpigmentation were noted after treatment with copper vapour laser.

Adolescent↗