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Biomedical subjects

Kenneth A Arndt

Publications and source records attributed to Kenneth A Arndt.

At least 19 recordsLinked to original sources
PubMed2006

A quality rating scale for aesthetic surgical procedures.

BACKGROUND: Cosmetic dermatologic procedures offer the promise of visible aesthetic enhancement with minimal risk. While in recent years the number of available procedures has proliferated, there are few objective methods for evaluating the relative quality of these procedures for particular indications or specific patients. OBJECTIVE: (A) To develop a simple, easy-to-use numerical rating scale to assess the quality of cosmetic surgical procedures on a range of parameters pertaining to clinical efficacy and patient satisfaction; (B) to statistically validate the discriminative value of this rating scale. METHODS: (A) Patient and physician interviews were performed to elicit a list of factors that may collectively characterize the clinical efficacy and patient tolerability of cosmetic dermatologic procedures. A 0-100 point rating scale was developed based on these factors, with the face-validity of this scale checked by a group of patients and physicians; (B) Statistical analysis of the questionnaire was performed by asking 15 expert cosmetic dermatologic surgeons to use it to rate 23 common cosmetic dermatologic procedures, and analyzing the results. RESULTS: (A) An easy-to-use scale was constructed to assess the quality of cosmetic dermatologic procedures by rating the associated cost, risk, time (procedure and recovery), discomfort, results, and longevity of benefit. A "physician adjustment factor" was used to further increase the relevance of this 0-100 point scale for specific patients; (B) Repeated-measures analysis of variations (ANOVAs) performed on the data from the survey of experts demonstrated that this scale can be used to discriminate between common dermatologic procedures. The differences in mean subscores and total scores among procedures grouped by anatomic site and target lesion-type were significant at the level of P < .05. LIMITATIONS: Patient preferences exogenous to the rating scale may increase or decrease the suitability of specific procedures. CONCLUSIONS: Common cosmetic dermatologic procedures are of uniformly high quality, as per expert ratings on a systematic measure. This quality rating scale appears statistically valid and robust, given that expert raters assigned similar ratings to the same procedures but mean ratings were different across procedures. In the future, this quality rating scale can be used to assess novel interventions, and to help dermatologic surgeons faced with patient concern to optimally select among alternative procedures for a given indication.

Botulinum Toxins, Type A↗
PubMed2006

Clinical effect of a single pulsed dye laser treatment of fresh surgical scars: randomized controlled trial.

BACKGROUND: Pulsed dye laser has been used to decrease erythema and telangiectasia associated with scars, including surgical scars. There is limited evidence indicating improved surgical scar appearance if pulsed dye laser treatments are commenced immediately at the time of suture removal. OBJECTIVE: To determine whether a single one-pass pulsed dye laser treatment at the time of suture removal can improve the appearance of surgical scars. METHODS: Randomized controlled trial enrolling 20 patients (complete data for 17 patients) at two geographic sites, with blinded ratings of pre- and post-treatment photographs obtained at various time points. Included patients underwent elliptical excision for atypical nevi of the trunk and/or extremities, with at least one resulting scar of at least 5 cm in length or two scars of at least 2.5 cm in length. For each patient, each scar or half-scar (if a larger scar was used) was randomized to treatment or control groups. Treatment scars received a single one-pass treatment with a 595 nm pulsed dye laser (Vbeam, Candela Corporation, Wayland, MA, USA) at the time of suture removal (ie, 2 weeks after excision) at the following parameters: 7 J/cm2 fluence, 7 mm spot size, 1.5-millisecond pulse duration, and 30-millisecond spray, 20-millisecond delay of dynamic cooling. The treatment area included 1 cm on either side of the scar, and the round laser spots were overlapped 10%. Control scars were not treated with laser. RESULTS: Immediate purpura was induced from the laser treatment Six weeks after laser treatment, no significant difference was found in the clinical appearance of surgical scars treated with a single pulsed dye laser treatment on suture removal day versus those surgical scars not treated with laser. Parameters on which no significant difference was found included visibility of incision, erythema, hyperpigmentation, hypopigmentation, induration, and atrophy. Both sets of scars improved over time. CONCLUSIONS: A single pulsed dye laser treatment at the time of suture removal does not appear to have a beneficial effect on clinical scar appearance. The point of minimal benefit for such laser treatments may lie somewhere between one and three treatments.

Adult↗
PubMed2006

Patient satisfaction and reported long-term therapeutic efficacy associated with 1,320 nm Nd:YAG laser treatment of acne scarring and photoaging.

BACKGROUND AND OBJECTIVE: Nonablative laser treatments have become increasingly used for the treatment of acne scarring and photoaging. While nonablative laser treatments are more convenient and relatively safer than ablative laser resurfacing, efficacy and patient satisfaction with the level of improvement of textural abnormalities in acne scarring and rhytids associated with photoaging needs further study. DESIGN/MATERIALS AND METHODS: Structured interviews were performed with 34 patients from a referral-based academic practice who each previously received a series of 6 monthly treatments with a 1,320 nm neodymium:yttrium-aluminum-garnet (Nd:YAG) laser for treatment of acne scarring or photoaging. Topical anesthesia was applied 1 hour before each treatment. Patients were interviewed at least 3 months after cessation of treatment (range 3-12 months). RESULTS: Patients tolerated the treatments well. Combined results for acne scarring and photoaging patients were as follows: (a) patient satisfaction with treatment was rated at 62%, and (b) textural improvement was reported at 31% at the end of the six treatments, and 30% at the date of interview. When results were stratified by diagnosis, patient satisfaction was slightly higher for treatment of acne scarring than for photoaging. Overall degree of improvement on a 1-10 scale was 5.4 for acne scarring and 3.8 for wrinkling. CONCLUSION: Nonablative treatment with the 1,320 nm Nd:YAG laser induced significant patient-reported improvement in both acne scarring and photoaging. The majority of patients reported satisfaction with the degree of improvement.

Acne Vulgaris↗
PubMed2005

Topical 5-aminolevulinic acid combined with intense pulsed light in the treatment of photoaging.

BACKGROUND: The adjunctive use of 5-aminolevulinic acid (5-ALA) with intense pulsed-light (IPL) treatments has been suggested to increase the benefit of IPL for photoaging; however, to our knowledge, no controlled trials have been performed. DESIGN: A prospective, randomized, controlled, split-face study was designed. Twenty subjects participated in a series of 3 split-face treatments 3 weeks apart in which half of the face was pretreated with 5-ALA followed by IPL treatment while the other half was treated with IPL alone. Two additional full-face treatments (with IPL alone) were then delivered 3 weeks apart. Assessment of global photodamage, fine lines, mottled pigmentation, tactile roughness, and sallowness (on a scale of 0-4) was performed by a blinded investigator before each treatment and 4 weeks after the final treatment. Patients also completed an assessment at the conclusion of the study comparing their results with pretreatment photographs. RESULTS: All 20 volunteers completed the study. Pretreatment with 5-ALA resulted in more improvement in the global score for photoaging (16 [80%] subjects vs 9 [45%] subjects; P = .008) and mottled pigmentation (19 [95%] subjects vs 12 [60%] subjects; P = .008) than IPL treatment alone. More successful results were achieved on the side pretreated with 5-ALA compared with the side treated with IPL alone for fine lines (12 [60%] subjects vs 5 [25%] subjects; P = .008) and mottled pigmentation (17 [85%] subjects vs 4 [20%] subjects; P < .001). While there was noticeable improvement over baseline scores with respect to tactile roughness and sallowness, pretreatment with 5-ALA did not seem to enhance the results of the IPL treatment. The final investigator cosmetic evaluations (P=.0002) and subject satisfaction scores (P=.005) were significantly better for the 5-ALA-pretreated side. Both treatments were well tolerated, with little difference in the incidence or profile of adverse effects with or without 5-ALA pretreatment. CONCLUSIONS: The adjunctive use of 5-ALA in the treatment of facial photoaging with IPL provides significantly greater improvement in global photodamage, mottled pigmentation, and fine lines than treatment with IPL alone, without a significant increase in adverse effects. This combination treatment enhances the results of photorejuvenation and improves patient satisfaction.

Aged↗
PubMed2005

Adverse event reporting for botulinum toxin type A.

A recent article published in the Journal of the American Academy of Dermatology reviewed adverse events regarding botulinum toxin type A (BTX-A) reported to the Food and Drug Administration between 1989 and 2003. Although postmarketing surveillance is a vital mechanism to ensure drug safety, the events reported in this paper must be considered in context to be appropriately interpreted. The majority of data was related to therapeutic rather than cosmetic use. The proportion of serious adverse events was 33-fold higher for therapeutic use and no deaths were reported after cosmetic use. The data were derived from a spontaneous reporting system and do not include assessments of causality between the BTX-A and purported adverse events. The report notes that over a third of these events were related to off-label use of BTX-A, a common practice in dermatology, yet no significant differences were reported in rates of adverse events between on-label and off-label use. The report reflects a favorable safety profile for cosmetic use of BTX-A, and if misinterpreted, could lead to unreasonable conclusions regarding a product considered to be highly safe and effective.

Adverse Drug Reaction Reporting Systems↗
PubMed2005

Low-level laser therapy for wound healing: mechanism and efficacy.

BACKGROUND: Given the recent interest in light-emitting diode (LED) photomodulation and minimally invasive nonablative laser therapies, it is timely to investigate reports that low-level laser therapy (LLLT) may have utility in wound healing. OBJECTIVES: To critically evaluate reported in vitro models and in vivo animal and human studies and to assess the qualitative and quantitative sufficiency of evidence for the efficacy of LLLT in promoting wound healing. METHOD: Literature review, 1965 to 2003. RESULTS: In examining the effects of LLLT on cell cultures in vitro, some articles report an increase in cell proliferation and collagen production using specific and somewhat arbitrary laser settings with the helium neon (HeNe) and gallium arsenide lasers, but none of the available studies address the mechanism, whether photothermal, photochemical, or photomechanical, whereby LLLT may be exerting its effect. Some studies, especially those using HeNe lasers, report improvements in surgical wound healing in a rodent model; however, these results have not been duplicated in animals such as pigs, which have skin that more closely resembles that of humans. In humans, beneficial effects on superficial wound healing found in small case series have not been replicated in larger studies. CONCLUSION: To better understand the utility of LLLT in cutaneous wound healing, good clinical studies that correlate cellular effects and biologic processes are needed. Future studies should be well-controlled investigations with rational selection of lasers and treatment parameters. In the absence of such studies, the literature does not appear to support widespread use of LLLT in wound healing at this time. Although applications of high-energy (10-100 W) lasers are well established with significant supportive literature and widespread use, conflicting studies in the literature have limited low-level laser therapy (LLLT) use in the United States to investigational use only. Yet LLLT is used clinically in many other areas, including Canada, Europe, and Asia, for the treatment of various neurologic, chiropractic, dental, and dermatologic disorders. To understand this discrepancy, it is useful to review the studies on LLLT that have, to date, precluded Food and Drug Administration approval of many such technologies in the United States. The fundamental question is whether there is sufficient evidence to support the use of LLLT.

Animals↗
PubMed2004

Effect of volume and concentration on the diffusion of botulinum exotoxin A.

OBJECTIVE: To investigate whether the volume of solution used to inject equivalent units of botulinum exotoxin A affects the diffusion of toxin and areas of rhytid diminution in the treatment of dynamic forehead lines. DESIGN: Ten volunteers with dynamic forehead lines were included. Each study patient received a single injection at a point 2.5 cm above the orbital rim on either side of the forehead with equivalent units, but in different volumes, of botulinum exotoxin A. The sides of injection were randomized; one side of the patient's forehead was injected first with 5 U of botulinum exotoxin A in 0.25 mL (2 U/0.1 mL) of preserved saline in the midpupillary line, followed by injection of the other side with 5 U in 0.05 mL of preserved saline (2 U/0.02 mL). There was a 5-fold difference in volume injected. Subjects were evaluated 14 days later for total area affected during visual inspection of the subjects' foreheads during active muscle contraction. SETTING: Private dermatology office. MAIN OUTCOME MEASURE: Visual inspection to measure the area of rhytid effacement in both height and width. RESULTS: The area affected by the botulinum exotoxin A injection was 50% greater in the side with the larger volume in 9 of 10 subjects. The average area affected was 6.05 cm(2) for the injection of the larger volume compared with 4.12 cm(2) for the injection with the smaller volume. The shape of rhytid effacement was oval, rather than round, with the average width longer than the average height. CONCLUSIONS: In this prospective, randomized, controlled study, we found that injection of botulinum exotoxin A in low concentration and higher volume resulted in greater diffusion and a larger affected area. The pattern of toxin spread is altered by muscular contraction in the injected sites. These results show that the dilution has implications on the desired effect of botulinum exotoxin A.

Adult↗
PubMed2004

Clinical evaluation of enhanced nonablative skin rejuvenation using a combination of a 532 and a 1,064 nm laser.

BACKGROUND AND OBJECTIVES: Improvements in the physical signs of photoaging can be achieved by non-invasive laser resurfacing procedures. To evaluate the effectiveness and safety of the Nd:YAG 1,064 nm and KTP 532 nm lasers for non-invasive skin rejuvenation. STUDY DESIGN/PATIENTS AND METHODS: Subjects requesting non-invasive skin rejuvenation underwent two treatments with the 532 nm laser to one side of the face and with both lasers to the other side, followed by three treatments with the 1,064 nm laser to both sides. Skin characteristics were evaluated before, during, and up to 4 months after treatment. RESULTS: A >25% improvement in overall skin condition was observed for >30% of subjects at the 1 month follow-up and >40% of subjects at the 4 month follow-up. The greatest improvements were observed for visual dryness, roughness, and uneven pigmentation. No adverse events were reported. There was a trend for greater improvement in patients who received more 1,064 nm treatments but this was not statistically significant. CONCLUSIONS: The 532 nm KTP and 1,064 nm Nd: YAG lasers can be effectively and safely used for non-invasive skin rejuvenation.

Combined Modality Therapy↗
PubMed2003

A prospective survey of patient experiences after laser skin resurfacing: results from 2 1/2 years of follow-up.

BACKGROUND: Laser skin resurfacing (LSR) is a common cosmetic surgical procedure, yet there are no prospective long-term studies on patients' perceptions of their procedure. OBJECTIVE: To prospectively document patients' subjective experiences after LSR. DESIGN: Twenty-seven consecutive patients who underwent combination carbon dioxide/erbium:YAG full-face laser resurfacing for acne scarring or photodamage were surveyed at postoperative days 1 and 3, within 1 week, at 3 weeks, 6 weeks, 3 months, and 30 months and asked standardized questions. SETTING: Referral-based academic practice. RESULTS: One day after LSR, 10 patients (37%) were concerned about the outcome, and 3 (11%) considered it a "terrible" experience. At 2.7 days after the procedure, 23 patients (85%) would recommend LSR, and after 3.7 days, 24 (89%) would have the procedure again. At 3 months, the patients' mean rating of appearance was 2.3 (0-3 scale), and all 27 (100%) felt that their appearance had been improved by LSR. After 30 months, 18 patients (75%) would recommend the procedure, 17 (71%) would have LSR again, 21 (88%) felt that their appearance was improved, and final appearance was rated 1.8 (0-3 scale). Patients undergoing LSR to treat acne scarring were as satisfied as patients treated for photodamage. CONCLUSIONS: Data on the evolution of patient perspective after LSR can improve patient preparation. This may help the surgeon and patient achieve shared, realistic expectations for the postoperative period and for long-term results.

Acne Vulgaris↗
PubMed2003

Nonablative laser and light treatments: histology and tissue effects--a review.

BACKGROUND AND OBJECTIVES: Nonablative laser and light treatments have largely replaced ablative laser therapy in clinical use for the improvement of the visible signs of cutaneous photoaging, including rhytides, vascular lesions, and pigmentation. However, the mechanisms underlying the reported clinical efficacy of nonablative treatments are not well-understood. The purpose of this analysis is to critically evaluate what is known about histologic and tissue effects of nonablative laser therapy and suggest future directions for research. STUDY DESIGN/MATERIALS AND METHODS: This is a review of the English language literature pertaining to nonablative laser and light treatments available through MEDline (1995-2002), and unpublished reports presented at major national meetings. Only studies that included harvesting and analysis of tissue samples are included. RESULTS AND CONCLUSIONS: (a) Thermal injury to the dermis in association with epidermal cooling most likely affects the dermal vasculature, which initiates a cascade of inflammatory events that includes fibroblastic proliferation and apparent up-regulation of collagen expression; (b) There is no indication that nonablative treatments are harmful or able to induce skin cancer; (c) It is possible that the horizontally distributed collagen reported after nonablative treatments is a "microscar," an enlarged Grenz sone associated with repetitive photo-induced trauma; (d) Further research is needed to elucidate the biophysical mechanisms underlying nonablative treatment, as well as to distinguish the utility of different wavelengths on epidermal and dermal improvement.

Cold Temperature↗
PubMed2003

A prospective trial of fungal colonization after laser resurfacing of the face: correlation between culture positivity and symptoms of pruritus.

BACKGROUND: After full-face laser resurfacing of the face, patients often complain of pruritus, which may be intense. It has been suggested that some cases of postresurfacing pruritus may be associated with subclinical fungal infection. OBJECTIVE: To determine whether intense pruritus after laser resurfacing of the face is correlated with simultaneous fungal growth of the treated skin. METHODS: Twelve adult female patients undergoing combined full-face laser resurfacing with CO2 and erbium:YAG lasers for chronic photodamage or acne scarring were enrolled in a prospective study. Fungal cultures were obtained by swabbing the facial skin of each patient immediately before, 3 days after, and 6 days after the laser procedure. At the same points in time, investigators completed objective assessments of the patients' facial skin, and patients reported the sensations that they were experiencing. RESULTS: Six patients (50%) complained of significant pruritus (3 or greater on a scale of 0 to 5). In four of the six cases (67%), at least one of the three fungal cultures obtained grew fungal organisms, including Candida albicans (2 cultures), Candida parapsilosis, Aureobasidium pullulans, and Fusarium species. In no instances did culture positivity occur in the absence of significant pruritus. A statistically significant relationship (P=0.0143) was found to exist between at least one of the three cultures being positive and the emergence of significant posttreatment pruritus. Physician ratings of clinical signs did not correlate with patient reports of pruritus, other symptoms, or culture positivity. CONCLUSION: Colonization or subclinical infection with fungi, particularly Candida spp., may be associated with significant postlaser resurfacing pruritus. Antifungal prophylaxis may mitigate this discomfort. Further research is required to confirm and expand these results.

Adolescent↗
PubMed2003

Treatment of facial telangiectasia with variable-pulse high-fluence pulsed-dye laser: comparison of efficacy with fluences immediately above and below the purpura threshold.

BACKGROUND: : Pulsed-dye laser treatment has been shown to be highly effective for the treatment of facial telangiectasia. Posttreatment purpura after such treatment has limited patient acceptance of the procedure. OBJECTIVE: : To determine whether purpura-free treatment with recently introduced variable-pulsed pulsed-dye lasers can effectively reduce facial telangiectasia. METHODS: : This was a prospective, randomized, controlled, nonblinded trial. Eleven patients received variable-pulse pulsed-dye laser treatment with and without induction of purpura. Telangiectasia were graded on a "telangiectasia density scale," on which a 1 signified extremely fine, sparsely distributed telangiectasia, and 5 referred to thick, ropelike telangiectasia covering the affected area. For each subject, two areas on either side of the facial midline with equivalent telangiectasia density ratings were randomized to the purpura and purpura-free treatment groups, respectively. All treatments used a 7-mm spot size and a 10-ms pulse duration. The fluence associated with the purpura threshold for each patient was determined in test areas. Purpura-free treatment entailed a fluence 1.0 J/cm2 less than the purpura threshold, and purpura-level treatment entailed a fluence 0.5 J/cm2 greater than the threshold. RESULTS: : Six weeks after a single purpura-free treatment, mean telangiectasia ratings were reduced from 2.7 to 2.4. Purpura-level treatments resulted in a decrease to 1.4 from the same baseline. Thicker, denser telangiectasia appeared to benefit more from purpura-level treatment (a mean telangiectasia density scale reduction of 1.7) than finer, sparser telangiectasia (a mean reduction of 0.8). In 81% of cases, both investigators and patients rated the side treated with purpura as undergoing a greater reduction in telangiectasia density. CONCLUSION: : Although facial telangiectasia do improve after a single purpura-free treatment with the variable-pulse pulsed-dye laser, they improve more after purpura is induced. Purpura-free and purpura-level treatments may be close to equivalent for treating fine telangiectasia, but purpura-level treatments have a distinct advantage for treating thicker telangiectasia. Significantly, the variable-pulse pulsed-dye laser offers patients the option of effective treatment of some telangiectasia without bruising.

Adult↗
PubMed2003

Clinically significant facial edema after extensive treatment with purpura-free pulsed-dye laser.

BACKGROUND: Long-pulsed pulsed-dye lasers permit treatment of facial erythema and telangiectasia with purpura-free technique, which may be more comfortable for the patient than purpura-inducing treatment. However, there are anecdotal reports of treatment-associated discomfort even when purpura is not elicited. OBJECTIVE: To determine whether patients experience clinically significant erythema, edema, and pain after purpura-free treatment with pulsed-dye laser. METHODS: In this prospective, controlled study, subjects included 15 patients who were undergoing purpura-free treatment of diffuse erythema and fine telangiectasia of at least half the facial surface area with purpura-free pulsed-dye, and it included 15 age, gender, and skin-type matched control subjects who were undergoing similar treatments but with the induction of trace to mild purpura. Patients were seen in person and were surveyed by phone regarding symptoms and signs during their postoperative courses. RESULTS: Postoperative erythema of a mean 3.3-days duration and 3.4/5.0 intensity was reported by 73% (11 of 15) of the purpura-free patients. Among purpura patients, the duration was 5.6 days. The intensity was 4.0, and again, 73% of patients reported this finding. Postoperative edema occurred among 87% of purpura-free patients, but such edema occurred in all of the purpura patients, in whom it lasted longer and was more intense. Symptomatic eye swelling and uncomfortable/painful edema were seen in 27% and 20%, respectively, of purpura-free patients, but in 40% and 53% of purpura patients. Among purpura-free patients receiving fewer than 250 laser pulses per treatment, erythema and edema lasted less than 1 day and 2.5 days, whereas the mean durations were 3.4 and 5.0 days for purpura-free patients receiving greater than 250 pulses. CONCLUSION: Extensive purpura-free treatment for erythema and telangiectasia of the face with the long-pulsed pulsed-dye laser can lead to clinically significant erythema, edema, and discomfort in patients. The duration, magnitude, and frequency of these undesired effects are markedly less with purpura-free treatment compared with purpura-inducing treatment and are also less for less extensive purpura-free treatments.

Edema↗
PubMed2003

Treatment of reticular leg veins with a 1064 nm long-pulsed Nd:YAG laser.

BACKGROUND: Millisecond-pulsed Nd:YAG lasers have been developed for the treatment of reticular leg veins. OBJECTIVE: We evaluated the effectiveness of a single treatment with a 50 millisecond 1064 nm Nd:YAG laser in the treatment of reticular veins of the lower extremity. METHODS: Twenty patients with reticular veins measuring 1.0 to 3.0 mm in diameter received one treatment with a 1064 nm Nd:YAG laser (Coolglide, Altus, Burlingame, Calif) at fluences of 100 J/cm(2) and 50 millisecond pulse duration. Symmetric matched areas that were left untreated served as the control. Eleven patients were pretreated with a topical anesthetic cream for 1 hour before treatment and wore compression stockings for 5 days after treatment. Nine patients were treated without topical anesthesia and did not wear compression stockings. Percent clearing and side effects were determined by 3 nontreating physicians (at each respective site) comparing projected Kodachrome images 1 month and 3 months after treatment. Patients also performed a self-assessment of their results. RESULTS: Two-thirds of vessels measuring 1 to 3 mm in diameter cleared more than 75% with one treatment. Larger vessels appeared to improve more than smaller vessels. Immediate treatment discomfort was tolerable. Side effects were minimal and included superficial thrombosis, delayed bruising, hyperpigmentation, and matting. CONCLUSION: Millisecond-pulsed Nd:YAG lasers used with 50 millisecond pulses are effective in the treatment of reticular leg veins.

Adult↗
PubMed2003

Reduction in injection pain with botulinum toxin type B further diluted using saline with preservative: a double-blind, randomized controlled trial.

BACKGROUND: Injection with botulinum A exotoxin reconstituted with preserved saline has been shown to be less uncomfortable than injection with the same toxin reconstituted with preservative-free saline. OBJECTIVE: We sought to determine whether injection with botulinum toxin type B is similarly less painful when preservative-containing saline is used to further dilute the product. METHODS: We conducted a double-blind, randomized controlled trial. A total of 15 consecutive adult patients presenting for treatment of upper face dynamic lines received treatment to one side (left or right) of the face with toxin type B further diluted with preservative-containing saline, and to the other side with toxin type B further diluted with preservative-free saline. RESULTS: Of 15 patients, 13 (87%) reported less pain in the halves of their faces treated with the preservative-containing saline (P =.0006). Pain on the preservative-containing side was on average 32% less among patients as a whole, and 39% less among patients noting some reduction. The 95% confidence interval for pain reduction associated with preservative-containing injection was -46.9% to -16.1%. Neither investigators nor patients observed any difference in clinical efficacy between the 2 treatment sides. CONCLUSIONS: Use of preservative-containing saline to further dilute botulinum toxin type B can significantly decrease patient discomfort on injection.

Botulinum Toxins↗