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M A Trelles

Publications and source records attributed to M A Trelles.

At least 37 records · Page 2Linked to original sources
PubMed2000

The significance of orbital anatomy and periocular wrinkling when performing laser skin resurfacing.

Knowledge of orbital anatomy and the interaction of muscle contractions, gravitational forces and photoagingis fundamental in understanding the limitations of carbon dioxide (CO2) laser skin resurfacing when rejuvenating the skin of the periocular area. Laser resurfacing does not change the mimetic behavior of the facial muscles nor does it influence gravitational forces. When resurfacing periocular tissue, the creation of scleral show and ectropion are a potential consequence when there is an over zealous attempt at improving the sagging malar fat pad and eyelid laxity by performing an excess amount of laser passes at the lateral portion of the lower eyelid. This results in an inadvertent widening of the palpebral fissure due to the lateral pull of the Orbicularis oculi. Retrospectively, 85 patients were studied, who had undergone periorbital resurfacing with a CO2 laser using anew treatment approach. The Sharplan 40C CO2 Feather Touchlaser was programmed with a circular scanning pattern and used just for the shoulders of the wrinkles. A final laser pass was performed with the same program over the entire lower eyelid skin surface, excluding the outer lateral portion (e.g. a truncated triangle-like area),corresponding to the lateral canthus. Only a single laser pass was delivered to the lateral canthal triangle to avoid widening the lateral opening of the eyelid, which might lead to the potential complications of scleral show and ectropion. When the area of the crows' feet is to be treated, three passes on the skin of this entire lateral orbital surface are completed by moving laterally and upward toward the hairline. Patients examined on days 1, 7, 15, 30, 60, and one year after laser resurfacing showed good results. At two months after treatment, the clinical improvement was rated by the patient and physician as being "very good" in 81 of the 85 patients reviewed. These patients underwent laser resurfacing without complications. The proposed technique of periocular resurfacing prevents complications of scleral show and laxity in the lateral eyelid opening and even ectropion, because treatment conforms to the osseo-muscular anatomical relationship of eyelid structures.

Aging↗
PubMed2000

Effects of skin cleaning modes on the condition of collagen and elastin after laser resurfacing.

BACKGROUND: Laser resurfacing is now widely used for the treatment of facial wrinkles, photoaging and acne scars and is usually combined with comparatively aggressive methods of cleaning detritus off the treated area after each laser pass. OBJECTIVE: This study aims to evaluate two different cleaning methods (damp gauze or damp large-tip cotton buds) in order to elucidate their influence on the healing process, if any. The left or right preauricular area, chosen at random on 10 patients undergoing periocular and perioral resurfacing with the same laser system, was cleaned after each laser pass with damp gauze (Group G) and the contralateral side with the large-tip cotton buds (Group C). Post-resurfacing oedema and erythema were observed in the preauricular areas and rated by the same experienced observer immediately after treatment and at 14, 30, 45, 60 and 90 days. RESULTS: Oedema was slightly more noticeable initially in Group G patients, but the erythema was more intense and lasted longer in the gauze-cleaned tissue. The sites were biopsied at 90 days and the samples sent for blinded histological evaluation to assess the degree of collagen and elastin fibre compaction. The histology demonstrated that the tissue from Group G achieved, at 90 days, better compaction of collagen and elastin fibres than that from Group C. CONCLUSIONS: It is suggested that the abrasive action caused by the gauze adds to the existing stimulative inflammatory reaction following CO2 laser resurfacing, which augments the collagen and fibre compaction response in the tissue. Comparatively aggressive cleaning with damp gauze may therefore be preferable to other methods when performing laser resurfacing.

Aged↗
PubMed1999

Electron microscopy comparison of CO2 laser flash scanning and pulse technology one year after skin resurfacing.

BACKGROUND: The recent adaptation of laser technology in plastic and dermatologic surgery has provided a means to reduce efficiently the irregularities of the surface of the skin. Previous studies have analyzed the short- and medium-term clinical and histologic results of two laser systems: the Sharplan 40C SilkTouch and the 5000C Coherent Ultrapulse with Computer Pattern Generator (CPG). This paper contains the long-term ultrastructural findings observed with the aid of transmission electron microscopy (TEM). MATERIALS AND METHODS: Twenty skin biopsy specimens were taken from ten Caucasion patients, between 54 and 72 years of age, who had undergone facial skin resurfacing with a CO2 laser 1 year previously. The treated areas of the face were divided into two equal parts. One half of the face was treated with the Sharplan SilkTouch laser and the other half with the Coherent Ultrapulse laser. Using TEM, the cell composition of the epidermis was studied ultrastructurally, as were the dermal-epidermal junction (DEJ) and the different fibers and cells in the superficial and middle dermis. RESULTS: On the side treated by the Sharplan laser, little melanin was observed, the DEJ was thicker, and there were abundant collagen fibers well compacted in the dermis. Also present was abundant elastin fiber with scarce interstitial spaces. On the side treated by the Coherent, the melanin was abundant and the DEJ was well structured. There were fibroblasts with lax chromatin in the dermis and collagen fibers in the papillary dermis oriented in a vertical and horizontal manner in relation to the epidermis. There was little elastin. The interstitial spaces were abundant. CONCLUSIONS: The Sharplan laser system seems to provoke a significantly more intense tissue response, with abundant dermal collagen and elastic fibers. This indicates that the Sharplan 40C SilkTouch might produce longer lasting clinical effects.

Aged↗
PubMed1999

The filtrum remodelling with combined Er:YAG CO2 laser resurfacing.

BACKGROUND: Upper lip wrinkles develop with aging and they can be successfully treated with laser resurfacing. The treatment eliminates the wrinkles and, ideally, should also recover the aesthetic configuration. METHODS: This report includes 32 patients treated for wrinkles of the upper lip with the Derma K. The first pass was done using 29 J/cm2, 5 Hz, 3 mm collimated spot size, plus the CO2 laser 5 W, 50% duty cycle, 50% overlapping. Following this pass, Derma K was reprogrammed to emit only with the Er:YAG at 1.4 J/cm2, 10 Hz, approximately 50% overlapping and with a beam diameter of 3 mm. Then, several passes were done where wrinkles could still be seen, focusing on the area corresponding to the filtrum. Biopsies were taken to examine possible particular implications of underlying muscle and its role in the recovery of anatomic aesthetics of young lip characteristics when using the proposed technique. RESULTS: Using Derma K resurfacing with extra passes of the Er:YAG at relatively low density, at the aforementioned area, it was possible to achieve the recovery of the aesthetic youthful appearance of the upper lip. Also, the shape of the filtrum recovered its youthful appearance together with the cupid's bow shape. Histology samples collected at the end of resurfacing showed that the laser thermal effect was also related to muscle fibres due to the proximity of this layer to the dermis because of the narrow subcutaneous fat layer. CONCLUSION: The combination of Er:YAG and CO2 laser of Derma K has potential to enhance the results of resurfacing for elimination of wrinkles of the upper lip. Moreover, the fact that only one laser pass of high energy density is used permits clear and secure control of treatment, preventing complications and obtaining good results.

Adult↗
PubMed1999

Skin resurfacing improved with a new dual wavelength Er:YAG/CO2 laser system: a comparative study.

OBJECTIVE: The efficacy of a new dual wavelength Er:YAG and CO2 laser system was tested for skin resurfacing results on rabbits' ears and human facial skin. The dual wavelength laser delivers simultaneous pulses of low-energy CO2 and high-energy Er:YAG energies. Theoretically, combining the strengths of both laser types in one console should lead to improved clinical outcome. SUMMARY BACKGROUND DATA: The use of the laser for skin resurfacing and remodeling has dramatically increased over the past few years. The CO2 laser was the first laser to be used in this field, followed more recently by the E:YAG laser. Both lasers offer unique advantages and disadvantages. METHODS: The present study consists of an ear chamber experiment, conducted on eight rabbits, to examine vascular network formation, after laser resurfacing with a standard CO2 laser and the Er:YAG/CO2 laser. Resurfacing was also performed on human patients with the Er:YAG/CO2 laser and the results were compared with previously published results of CO2 laser resurfacing. RESULTS: Significant advantages, including an attenuation in the degree of edema and erythema and a shorter reepithelialization time compared to results with conventional CO2 systems, were observed with the Er:YAG/CO2 system. Improved tissue reorganization and good clinical results in nine of the ten patients (six ratings of "very good" and three "good") were observed. The clinical outcome of the remaining patient was rated as "fair." Minimal side effects were reported and observed in only three patients. The learning curve required to maximize the efficiency of the system is steep, however, requiring a thorough understanding of the different laser/tissue interactions associated with the two wavelengths. CONCLUSION: It is the authors' opinion that the dual wavelength Er:YAG/CO2 laser system offers a particularly efficient and flexible system to perform standard CO2 procedures for skin resurfacing with an improved clinical outcome, as well as other applications with the CO2 or Er:YAG energy delivered separately.

Aged↗
PubMed1998

The origin and role of erythema after carbon dioxide laser resurfacing. A clinical and histological study.

BACKGROUND: Transient erythema, which can last up to 3 months after carbon dioxide (CO2) laser skin resurfacing, is a usual side effect with pulsed or rapidly scanned CO2 lasers. OBJECTIVE: We evaluated the cause of erythema in the clinical setting and by histology in order to determine if and how we may decrease it, or even eliminate it. METHODS: Ten patients who underwent resurfacing were recruited to this study. Skin punch biopsies were taken at 0, 7, 21, and 90 days and analyzed by light microscopy. RESULTS: Erythema was noticed from about day 8, when the crusting on the skin surface was exfoliated. It reached its maximum intensity after 14 days, and had disappeared by 60-90 days. Histology showed an early inflammatory response, with an immature neopithelium, and rich vascularization. The normal epidermis had returned by 90 days, and during this period there was reduced optical scattering and absorption in melanin. CONCLUSION: Although the erythema is an unwanted side effect in the patient's eyes, it is to be expected and thus represents the effects of a combination of epidermal immaturity, reduced melanin absorption of light, reduced dermal optical scattering, and increased blood flow secondary to the surgically induced inflammatory response.

Aged↗
PubMed1998

A clinical and histological comparison of flashscanning versus pulsed technology in carbon dioxide laser facial skin resurfacing.

BACKGROUND: Two different carbon dioxide (CO2) laser systems are currently in use for skin resurfacing. The vast majority of lasers use a pulsed beam, like the Coherent 5000C, but Sharplan uses scanning technology. OBJECTIVE: We describe a clinical and histological comparison of these two laser technologies in order to determine if there are differences in the outcome. METHODS: Twenty-two female patients underwent facial skin resurfacing using the Coherent 5000C UltraPulse CPG on one side of the face and the Sharplan Silk Touch on the contralateral side of the face. The clinical appearances were assessed periodically after treatment and punch biopsies were taken preoperatively and after 7, 21, and 90 days. Tissue was stained with Hematoxylin-Eosin, Masson Trichrom, and with the Verhoeff technique. Histological evaluation was performed on randomized samples taken from the same patient. Epidermis/dermis expression, collagen compaction, and elastin fiber quantity were compared to evaluate if any differences existed. RESULTS: The side treated by Coherent healed more rapidly and with excellent cosmesis. Greater erythema was observed on the Sharplan side, but had disappeared at the 90-day evaluation. At this time the quality of the results was similar with no particular difference between the sides treated by the Coherent or the Sharplan lasers. At the histological level, although tissue recovered faster on the Coherent side at the 7-day control, at 90 days the collagen was better compacted and organized on the Sharplan side. Similarly, the quantity of the elastin was significantly more enhanced on the Sharplan side. CONCLUSION: Irradiated laser energy density in relation to time, and the way that it is delivered, should play an important role at the moment of producing collagen shrinkage. The SilkTouch delivers laser energy more aggressively, thereby producing a more intense inflammatory tissue reaction, which results in slower recovery of tissue, compared with the Coherent CPG. More active enhancement of vascularization found in the Sharplan is likely to be the reason for a more effective collagen proliferation and compaction. These changes, together with the increase in elastin in the dermis, may produce longer lasting effects in skin resurfacing.

Adult↗
PubMed1996

Possible mechanisms for an irregular vessel coagulation when long laser pulses are used in the treatment of port-wine stains.

The laser treatment of port-wine stains (PWS) has as a main aim the irreversible damage of ectatic vessels. Blood content of the subcutaneous venous plexus in PWS can be increased by a factor of seven or more, compared to that of the normal skin. The venous blood velocity ranges from 0.1-1 mm/s in capillaries to approximately 22 mm/s in larger vessels of about 300 microns in diameter. A PWS, selected for study, was irradiated with a multiline argon laser 488/515 nm wavelength, 1.5 W power, 200 ms pulse duration, 0.5 mm beam diameter and repetition frequency up to 5 Hz. Laser shots were placed adjacently in an area of 1 cm2. Using these parameters, in the case of dilated PWS vessels with an optical penetration depth and thermal diffusion length less than the diameter of the vessel, together with a transit time of blood across the irradiated spot less than the pulse duration, and estimating that during a pulsed laser emission of 200 ms, the blood has travelled a distance of 3-4 mm, there is a strong indication that hemodynamics during irradiation may influence the pattern of coagulation and agglutination. Thrombosis should occur in the case of small vessels and, in larger vessels, the coagulated blood will only partly fill the lumen. The structure developed in the vessel interior may also change continuously with time, as the coagulated material is progressively replaced by fibrotic tissue and the irregular agglutination pattern may be due to inhomogeneity in the absorbed optical energy.

Biophysical Phenomena↗
PubMed1996

Carbon dioxide laser transconjunctival lower lid blepharoplasty complications.

Lower eye lid blepharoplasty is a frequent cosmetic procedure. The carbon dioxide laser transconjunctival approach is a popular alternative to conventional techniques. Eight hundred eighty-nine consecutive cases were studied retrospectively to determine the occurrence of complications. All cases were included. Complications were divided into intraoperative, immediate postoperative (days 1-7) and late postoperative (greater than 7 days). Complications encountered in this study of carbon dioxide laser conjunctival blepharoplasty were uncommon and not severe.

Adult↗
PubMed1996

Penetration depth of Ultrapulse carbon dioxide laser in human skin.

BACKGROUND: Recent technological advances have dramatically increased the use of lasers in skin resurfacing. The first high-power short-pulse laser, Ultrapulse, has found extensive use in dermatology and plastic surgery for skin resurfacing. Reports for penetration depth are at best anecdotal. To our knowledge this is the first report of histological effects of the Ultrapulse in human skin. OBJECTIVE: To determine the effect of single and repeated (two or three) Ultrapulse laser impacts on volar forearm skin. METHOD: The volar surface of the arm in four patients received in adjacent areas either one, two, or three pulses, after anesthesia. The treated areas were immediately biopsied, hematoxylin & eosin prepared, and examined. RESULTS: Increasing the number of passes correlates with increased depth of penetration and thermal ablation. No significant propagation of destructive thermal energy to adjacent tissue was noted. CONCLUSION: One impact at the tested parameters ablated most of the epidermis. Two impacts superimposed ablated the entire epidermis and the superficial papillary dermis. Three superimposed impacts penetrated to the reticular dermis.

Adult↗
PubMed1994

Improving the results of facial dermal lesions elimination by laser.

Argon laser therapy of superficial pigmented lesions in both young and old people is associated with a risk of complications including delayed wound closure and hypo/hypertrophic scarring. Problems may also occur after treatment of lesions located on the eyelid. To minimize the risk of these problems coagulation of deep tissue should be avoided. We discuss a technique using mercurochrome, a red-colored compound that absorbs the blue and green lines of the argon laser, as a barrier for the irradiated light that eliminates these complications and we provide probable reasons for this technique's effectiveness.

Humans↗
PubMed1993

Defining purpura.

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Hemangioma↗