PubMed Health⌕ Search

Biomedical subjects

R G Wheeland

Publications and source records attributed to R G Wheeland.

At least 19 recordsLinked to original sources
PubMed1995

Clinical uses of lasers in dermatology.

The accessibility of the skin to examination and study has permitted dermatologists to play an extremely important role in defining the clinical usefulness and limitations of many laser systems as well as developing innovative concepts, techniques and devices that further improved the effectiveness of laser treatment. As new laser technology evolved over the years, dermatologists have also helped define the specificity of laser-tissue interaction and employed the newly developed laser technologies in innovative ways which further expanded the usefulness of these devices. One of the most important concepts to be developed by dermatologists--selective photothermolysis--has led to the creation of a series of laser systems which have provided numerous unique advantages in the management of many common vascular and pigmented conditions of the skin and mucous membranes, even in infants and children. The net result of these technologic advances has been the creation of new and effective treatment techniques which have been so profoundly superior to existing technology that they have been rapidly incorporated into the daily practice of most dermatologists.

Dermatologic Surgical Procedures↗
PubMed1995

Cosmetic use of lasers.

During the 35 years of their existence, lasers have assumed an ever-expanding role in cosmetic surgery due to their reproducible precision in effectively managing a number of cutaneous conditions and disorders for which no acceptable form of treatment has been developed. Current medical lasers can be used to fade or remove many vascular and pigmented birthmarks, decorative and traumatic tattoos, solar and rosacea telangiectasia, and many acquired pigmentary disorders, without a visible scar or change in texture. In order to provide their patients with the best possible aesthetic result, cosmetic surgeons should be familiar with the advantages, disadvantages, and potential complications of lasers.

Esthetics↗
PubMed1994

Treatment of epidermal pigmented lesions with the frequency-doubled Q-switched Nd:YAG laser. A controlled, single-impact, dose-response, multicenter trial.

BACKGROUND AND DESIGN: The removal of benign, aesthetically important, pigmented lesions can be effectively treated with multiple modalities. Selective removal of the pigment by lasers is becoming increasingly popular. A three-center trial evaluated the effectiveness of the frequency-doubled Q-switched neodymium (Nd):YAG laser (532 nm, 2.0-mm spot size, 10 nanoseconds) in removing benign epidermal pigmented lesions with a single treatment. Forty-nine patients were treated for multiple lentigines (n = 37), for cafe au lait macules (n = 7), and for miscellaneous lesions (n = 5). Treatment areas were divided into four quadrants, irradiated with fluences of 2, 3, 4, or 5 J/cm2 and evaluated at 1- and 3-month intervals following treatment. RESULTS: For lentigines, response was related to dose with a greater than 75% pigment removal achieved in 60% of those lesions treated at higher energy fluences. Responses were more variable with other lesions, with fair-to-good improvement noted in most cases. Mild, transient erythema; hypopigmentation; and hyperpigmentation were noted in several patients, but resolved spontaneously within 3 months. No other textural changes, scarring, or other side effects were noted. CONCLUSION: The frequency-doubled Q-switched Nd: YAG laser (532 nm) safely and effectively treats benign epidermal pigmented lesions.

Adult↗
PubMed1993

Treatment of port-wine stains for the 1990s.

BACKGROUND: A dramatic improvement in the treatment of patients with port-wine stains has occurred over the past 20 years owing to the availability of a variety of different laser systems. The argon laser was the first system to offer an advantage over the older surgical techniques that had previously been used to manage these patients. However, many new lasers have since been developed that further improved the treatment results while simultaneously reducing the risks, even when treating children. OBJECTIVE: To present the current status of laser surgery for port-wine stains and describe how the many newer systems are being used to more effectively manage these patients. METHODS: A thorough review of the medical literature was conducted on the use of new lasers, delivery systems, and treatment techniques for the management of port-wine stains. RESULTS: The biggest advance in laser treatment of port-wine stains resulted from the development of systems that are capable of delivering yellow light. The improved precision provided by these lasers serves to minimize epidermal injury, limit nonspecific thermal damage, and permit treatment of newborns and young children without a significant risk of scarring. CONCLUSION: Major benefits in the treatment of port-wine stains have resulted from the recent development of many new laser systems and laser accessories that provide a more precise response with less potential for complications than had been previously attainable with older technologies.

Head and Neck Neoplasms↗
PubMed1993

Inflammatory carcinoma masquerading as erythema annulare centrifugum.

A case of inflammatory carcinoma, or carcinoma erysipelatodes, clinically resembling erythema annulare centrifugum is reported. The cutaneous inflammatory carcinoma was due to metastasis by a signet-ring cell adenocarcinoma, probably of gastrointestinal origin. This is the third reported case of inflammatory carcinoma with signet-ring cell infiltration. Cancer patients with atypical or unusual inflammatory dermatoses should be evaluated by skin biopsy because of the possible association with the internal neoplastic process.

Adenocarcinoma, Mucinous↗
PubMed1993

Precise ablation of skin with reduced collateral damage using the femtosecond-pulsed, terawatt titanium-sapphire laser.

BACKGROUND AND DESIGN: The precise ablation of skin was studied using an ultrashort-pulsed, high-intensity titanium-sapphire (Ti:Al2O3) laser capable of peak intensities of tens of terawatts (TW; 1 TW = 10(12) watts [W]) per square centimeter. Rat skin was exposed in vitro to femtosecond-pulsed Ti:Al2O3 laser radiation at 800 nm, while varying the number of pulses and the intensity up to 46 TW/cm2. Ablation was evaluated by monitoring the amount of tissue removed per pulse as a function of energy, and by light microscopic examination of damage to adjacent, nonirradiated tissue. OBSERVATIONS: Ablation depth per pulse was 0.1 micron at threshold intensity, and it was increased with both the energy per pulse and the number of pulses. Minimal damage to adjacent healthy tissue was observed, varying 0 to 30 microns. CONCLUSION: The results suggest that ablation of skin with femtosecond-pulsed, terawatt Ti:Al2O3 laser may have potential for precision cutaneous surgery, and in vivo studies are indicated.

Animals↗
PubMed1992

Low-energy helium neon laser irradiation does not alter human keratinocyte differentiation.

There are reports that low-energy HeNe irradiation can enhance wound healing in vivo. We have previously demonstrated that HeNe irradiation increases the motility of human epidermally derived keratinocytes in vitro. Here we investigate whether HeNe irradiation alters normal keratinocyte differentiation, which is essential for the formation of a normal, functioning epidermis. Subconfluent keratinocyte cultures were irradiated three times within 24 h with either 0, 0.8, 3, or 7.2 J/cm2. After cultures reached post-confluence, parameters of growth and differentiation, such as cell number, cornified envelope (CE) formation, and transglutaminase activity were measured. No significant differences were found between the control (0 J) and irradiated cultures in these assays. We also examined the pattern of newly synthesized keratins in cultures irradiated with 7.2 J/cm2 three times within a 24-h period. Both control and irradiated cultures exhibited similar keratin patterns. These results provide evidence that HeNe irradiations of up to 7.2 J/cm2 have no direct deleterious effect on normal keratinocyte differentiation needed for the formation of a functional epidermis. Hence, it is anticipated that the clinical use of the HeNe laser irradiance that enhances keratinocyte migration in vitro (0.8 J/cm2) to promote wound healing in vivo will not alter the ultimate integrity or differentiated function of the epidermis that migrates to cover the wounded area.

Cell Differentiation↗
PubMed1992

Analysis of the carbon dioxide laser plume for simian immunodeficiency virus.

To determine the viability of the immunodeficiency virus in the laser plume after carbon dioxide (CO2) laser irradiation, multiple samples of culture medium containing concentrated simian immunodeficiency virus (SIVMAC at 1000 TCID50 cultured from HUT 78 cells) were irradiated with a continuous-wave CO2 laser at variable irradiances (from 400 W/cm2 for 5 seconds to 1600 W/cm2 for 300 seconds). The resultant plume was collected and cultured for the presence of SIV. A positive control consisted of handling an infected specimen identically to the test specimens, with the exception of CO2 laser irradiation. All test cultures remained negative over an 8 week incubation period, while the control was positive for viable SIV within 7 days. These results suggest that SIV is not viable in the laser plume after CO2 laser irradiation. Further investigation is necessary before extrapolating these results to the human immunodeficiency virus (HIV).

Carbon Dioxide↗
PubMed1991

Current issues in the performance of Mohs micrographic surgery.

Recently, a survey was sent to all members of the American College of Mohs Micrographic Surgery and Cutaneous Oncology concerning their performance of Mohs micrographic surgery. Responses to numerous questions regarding the daily practice of this technique revealed that many useful modifications have evolved over the years that serve to enhance the efficacy and the efficiency of the original Mohs surgical procedure. The results of this survey are presented and discussed.

Humans↗
PubMed1991

Use of the argon-pumped tunable dye laser for port-wine stains in children.

The authors reported previously a new technique using a low power argon-pumped tunable dye laser at a wave-length of 577nm (yellow light) to treat port-wine stains in adults. The authors report their results using this same technique as a form of treatment for 92 children with facial port-wine stains.

Adolescent↗
PubMed1991

Reconstruction of the lower lip and chin using local and random-pattern flaps.

Unlike the reconstruction of wounds found on more predictable and less variable anatomic subunits of the face, reconstruction of defects on the chin and lower lip often present special difficulties for the surgeon in accurately assessing and selecting the lines of incision that will provide the patient with the best cosmetic result. The author discusses the many factors which must be considered as part of that selection process and describes the uses of the most common local flaps for reconstructing wounds found in this anatomic location.

Chin↗
PubMed1991

Lasers 1990.

Explore the source record for details and available documents.

Argon↗
PubMed1990

Low-energy helium-neon laser irradiation increases the motility of cultured human keratinocytes.

Helium-neon (HeNe) laser irradiation is known to stimulate wound healing. We investigated whether the biostimulatory effects of HeNe irradiation result from enhancement of keratinocyte proliferation or motility. HeNe effects on keratinocyte motility were evaluated by irradiating a "wounded" culture with 0.8 J/cm2 3 times over a 20-h period. At 20 h post-irradiation, videocinemicroscopy and sequential quantitative measurements of the leading edge were taken over a 6-h period. There was a significant difference in migration of the leading edge in irradiated "wounds" compared to non-irradiated "wounded" controls (12.0 microns/h vs 4.0 microns/h, p less than 0.0001). To determine if the increase in migration observed in irradiated cultures resulted from a proliferative effect of HeNe irradiation, subconfluent human keratinocyte cultures were irradiated with single or multiple doses of different fluences of HeNe irradiation (0.4 to 7.2 J/cm2) and evaluated 72 h post-irradiation. Irradiated and non-irradiated keratinocyte cultures grown on a microporous membrane surface were co-cultured with irradiated and non-irradiated fibroblasts to determine if HeNe irradiation induced a paracrine effect on keratinocyte proliferation. No significant increase in keratinocyte proliferation was demonstrated in any of these treatments. The biostimulatory effects of HeNe irradiation may now be extended to include enhancement of keratinocyte motility in vitro; this may contribute to the efficacy of HeNe irradiation in wound healing.

Cell Division↗
PubMed1990

Flashlamp-pumped pulsed dye laser therapy for poikiloderma of Civatte.

The use of pulsed yellow light from a flash-lamp-pumped pulsed dye laser has provided a successful form of therapy to remove both the telangiectasias and irregular pigmentation associated with poikiloderma of Civatte. The short pulse duration and specificity of the interaction between yellow light and hemoglobin permit this technique to be performed on the thin skin of the neck without textural changes or scarring. Furthermore, use of the large beam diameter of this laser system allows for rapid treatment of large areas in a short period of time.

Humans↗
PubMed1990

A superior method of tattoo removal using the Q-switched ruby laser.

The Q-switched ruby laser was used to treat 101 amateur and 62 professional tattoos in 80 patients over a period of 22 months. Using a 5- to 8-mm spot size and energy fluences of 2-4 joules/cm2, an average of three retreatments resulted in complete pigment removal in four, nearly complete pigment removal in 84, significant pigment removal in 11, and minimal pigment removal in two amateur tattoos. Using identical parameters for professional tattoos, there was complete pigment removal in two, nearly complete pigment removal in five, significant pigment removal in 18, minimal pigment removal in 25, and very little pigment removal in 12. Professional tattoos with red, yellow, and green pigments faded, but required multiple retreatments. While transient hypopigmentation occurred in many patients, skin texture and hair growth returned to normal in all cases and no hypertrophic scarring was seen.

Adolescent↗
PubMed1990

Treatment of massive rhinophyma with the carbon dioxide laser.

A case of massive rhinophyma that produced significant functional and cosmetic difficulties was treated using the carbon dioxide laser. Minimal bleeding occurred during the operative procedure despite the grotesque enlargement and high degree of vascularity of the skin and soft tissue. Using this technique, restoration of normal function and excellent cosmesis was possible without complication.

Aged↗