Radiofrequency volumetric reduction for masseteric hypertrophy

A Multicenter Phase II Study Evaluating the Safety and Efficacy of Botulax in Asian Patients with Benign Masseteric Hypertrophy

BACKGROUND

Benign masseteric hypertrophy (BMH) is a condition in which the thickness of the masseter muscle is increased, resulting in jawline prominence with an undesirable cosmetic appearance. Botulinum toxin type A (BTA) injection is a promising treatment option, but its effective dose remains debated.

METHODS

Adults older than 19 diagnosed with BMH through visual examination and palpation related to a masseter muscle prominence were selected, and 80 patients were randomly assigned into five groups (placebo group and four groups with different doses of BTA: 24 U, 48 U, 72 U, or 96 U, on both sides of the jaw) and treated with placebo or BTA once at their baseline visit. During each follow-up, the treatment efficacy was evaluated with ultrasound examination of the masseter muscle, three-dimensional facial contour analysis, visual evaluation by the investigator, and patient satisfaction evaluation.

RESULTS

The mean age of the 80 patients was 42.7 ± 9.98 years; 68.75% were women. The mean change in masseter muscle thickness during the maximum clenching state after 12 weeks of drug administration compared with baseline in the 24-U, 48-U, 72-U, and 96-U groups were -2.33 ± 0.41 mm, -3.35 ± 0.42 mm, -2.86 ± 0.42 mm, and -3.79 ± 0.42 mm, respectively. All treatment groups showed a statistically significant decrease compared with placebo. Regarding subjective satisfaction, all treatment groups, except the 24-U group at 4 weeks, showed higher satisfaction than the placebo group during all visits. No significant adverse events were noted.

CONCLUSION

BTA administration of at least 48 U for BMH is more cost-effective than high-dose units and has a low risk of side effects.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, II.

Ultrasound-guided five-point injection of botulinum toxin for patients with trapezius hypertrophy

OBJECTIVES

Our study aimed to explore the clinical therapeutic effects of ultrasound-guided five-point injection of botulinum toxin type A for patients with trapezius hypertrophy.

METHODS

Twenty female patients diagnosed with trapezius hypertrophy were enrolled in this study. The thicknesses of the trapezius muscle were measured by using the ultrasound scanner to locate the thickest point of trapezius, followed by labelling the other four points around the first point. Botulinum toxin type A was injected bilaterally (50 IU/side, 5 points/side) in the trapezius muscle of these patients. The surgery effects were evaluated by thicknesses of the trapezius muscle, intramuscular needle electromyographic and electroneurographic examinations, appearance changes and patients' satisfactions.

RESULTS

Statistically significant differences in thicknesses of the trapezius muscle were observed at 4 weeks (p < 0.001), 12 weeks (p < 0.001), 20 weeks (p < 0.001), 28 weeks (p = 0.011), 36 weeks (p = 0.022), and 44 weeks (p = 0.032) after surgery. The latencies of trapezius muscle became longer at 12 weeks after surgery (left: 2.40 ms, right: 2.53 ms vs. left: 1.75 ms, right: 2.00 ms). Electroneurographic results showed amplitude reduction of compound muscle action potentials (CMAPs) at 12 weeks after surgery (left: 1.91 uV, right: 3.10 uV vs. left: 15.00 uV, right: 15.40 uV). Obvious appearance changes were revealed at 12 weeks after surgery. All of 80% patients were very satisfied, 15% patients were relatively satisfied, and 5% patients were not satisfied with the surgery.

CONCLUSION

Ultrasound-guided five-point injection of botulinum toxin type A might be effective for patients with trapezius hypertrophy.

Auxiliary usage of botulinum toxin A in plastic surgery in China

BACKGROUND

Currently, botulinum toxin A (BTA) is mainly used in the treatment of muscle spasms and in cosmetic procedures, and its cosmetic indications are expanding rapidly. There have been sporadic reports focused on the preoperative usage of BTA complementing plastic surgery. We briefly summarize the current experience of BTA complementing plastic surgery in China based on clinical experience.

METHODS

We reported a brief review of the preoperative use of BTA as an accessory to plastic surgery (blepharoplasty, chin augmentation, mandibular angle ostectomy, rhinoplasty, hyaluronic acid fillers injection for wrinkle reduction) based on previous studies and our experience.

RESULTS

Preoperative treatment with BTA in plastic surgery helps surgeons operate and results in better cosmetic results.

CONCLUSIONS

Preoperative BTA treatment can reduce the occurrence of surgical complications as well as improve the surgical results in some plastic surgeries. The procedure is suitable for clinical application and worth promoting.

Aesthetic and Non-aesthetic Indications for Orbicularis Oculi Myectomy

INTRODUCTION

Crows' feet wrinkles are caused by the action of the orbicularis oculi muscle on overlying skin. Treatment options range from botulinum toxin to a multitude of surgical methods. We first described our technique in 2003 and refined it in 2006. We highlight the evolution of our technique and look at our results to assess the effectiveness of our technique.

OBJECTIVE

The aim of this article is to show our experience of 13 years in 134 patients with our technique of orbicularis oculi myectomy.

METHODS

From September 2000 to July 2013, we operated on 134 patients with an age range of 28-77 years. Of these patients, 104 had myectomies via lifting and 22 via a blepharoplasty approach. Five patients had myectomies for treatment of blepharospasm and a further three patients to restore symmetry in facial palsy. An evaluation of the results was performed by two medical students.

RESULTS

Our results showed reduction of the wrinkles in all cases. For the statistical analysis the Wilcoxon test was performed. The p value was less than 0.001 showing a significant reduction of crows' feet wrinkles in both sides when the orbicularis myectomy was performed, via blepharoplasty or lifting. For myectomy performed for blepharospasm or facial palsy, the statistical analysis was not done due to the low numbers.

CONCLUSION

In the appropriate patient, orbicularis oculi myectomy is an effective and long-term treatment for crows' feet wrinkles with a low risk of complications and high patient satisfaction.

LEVEL OF EVIDENCE IV

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Aesthetic use of BoNT: Options and outcomes

There are a multitude of uses for BoNT in the aesthetic realm. Efficacy has been shown in softening glabellar creases, crows feet, forehead rhytides, and in correcting facial asymmetries, including mild eyelid ptosis. Facial shape can be altered through injections of BoNT into masseter, and smiles can be altered with BoNT. Clinical examples of the above will be shown, as well as adverse outcomes with inaccurate injection techniques.

A comparative study of the efficacy and safety of radiofrequency ablation and botulinum toxin A in treating masseteric hypertrophy

The aim of the present study was to evaluate the effects of two treatments for masseteric hypertrophy. In total, 24 patients with masseteric hypertrophy were enrolled in this study. Patients were randomly divided into two groups: 12 individuals were treated with radiofrequency (RF) ablation and 12 patients received an injection of botulinum toxin A. The thickness of the masseter muscle under tension was measured using ultrasound and clinical photographs were captured prior to treatment and at 6 and 12 months following treatment. Complications were observed during 12-month follow-up. In the group injected with botulinum toxin A, masseteric muscle thickness decreased to the lowest point 6 months after the injections but increased until 12 months after injection. However, in the group treated with RF ablation, muscle thickness decreased steadily over the 12 months following surgery. Therefore, the results of the present study indicated that the effect of RF ablation on the thickness of the masseter muscle may be much larger than that obtained following injection with botulinum toxin A.

Surgical correction of crow's feet deformity with radiofrequency current

BACKGROUND

There are many published surgical techniques for the correction of crow's feet deformity, but subsequent contour irregularities and early recurrence are often reported.

OBJECTIVE

The authors present a radiofrequency (RF) technique to treat crow's feet that can prevent complications while simultaneously maintaining long-term results.

METHODS

From April 2010 to February 2012, a total of 52 consecutive patients (3 men and 49 women) underwent surgical correction of crow's feet with an RF current. Following elevation of the skin flap in the temporal area, the lateral portion of the orbicularis oculi muscle was partially elevated and splayed. Then the RF current was applied to the elevated muscle flap until the target temperature of 60°C to 80°C was reached. Clinical outcomes were observed through photographs with patients in a natural smiling position.

RESULTS

Mean (SD) patient age was 52.7 (2.2) years (range, 31-73 years). Patients were followed postoperatively during a mean period of 23 months (range, 15-36 months). There were no recurrences of crow's feet during the follow-up period. No major complications were noted.

CONCLUSIONS

The main advantage of this surgical technique is preserving continuity of the orbicularis oculi muscle while selectively decreasing muscle tone. Hence, this technique may prevent any contour irregularities. The RF current causes irreversible muscle fibrosis, which in turn provides long-lasting results. While the early results of this series show promising long-term efficacy and a good safety profile, the small number of patients and short-term follow-up period warrant further study.

Botulinum toxin for masseter hypertrophy

BACKGROUND

Benign masseter muscle hypertrophy is an uncommon clinical phenomenon of uncertain aetiology which is characterised by a soft swelling near the angle of the mandible. The swelling may on occasion be associated with facial pain and can be prominent enough to be considered cosmetically disfiguring. Varying degrees of success have been reported for some of the treatment options for masseter hypertrophy, which range from simple pharmacotherapy to more invasive surgical reduction. Injection of botulinum toxin type A into the masseter muscle is generally considered a less invasive modality and has been advocated for cosmetic sculpting of the lower face. Botulinum toxin type A is a powerful neurotoxin which is produced by the anaerobic organism Clostridium botulinum and when injected into a muscle causes interference with the neurotransmitter mechanism producing selective paralysis and subsequent atrophy of the muscle.This review is an update of a previously published Cochrane review.

OBJECTIVES

To assess the efficacy and safety of botulinum toxin type A compared to placebo or no treatment, for the management of benign bilateral masseter hypertrophy.

SEARCH METHODS

We searched the following databases from inception to April 2013: the Cochrane Central Register of Controlled Trials (CENTRAL); MEDLINE (via PubMed); EMBASE (via embase.com); Web of Science; CINAHL; Academic Search Premier (via EBSCOhost); ScienceDirect; LILACS (via BIREME); PubMed Central and Google Scholar (from 1700 to 19 April 2013). We searched two bibliographic databases of regional journals (IndMED and Iranmedex) which were expected to contain relevant trials. We also searched reference lists of relevant articles and contacted investigators to identify additional published and unpublished studies.

SELECTION CRITERIA

Randomised controlled trials (RCTs) and controlled clinical trials (CCTs) comparing intra-masseteric injections of botulinum toxin versus placebo administered for cosmetic facial sculpting in individuals of any age with bilateral benign masseter hypertrophy, which had been self-evaluated and confirmed by clinical and radiological examination were considered for inclusion. We excluded participants with unilateral or compensatory contralateral masseter hypertrophy resulting from head and neck radiotherapy.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened the search results. For future updates, two authors will independently extract data and assess trial quality using the Cochrane risk of bias tool. Risk ratios (RR) and corresponding 95% confidence intervals (CI) will be calculated for all dichotomous outcomes and the mean difference (MD) and 95% CI will be calculated for continuous outcomes.

MAIN RESULTS

We retrieved 683 unique references to studies. After screening these references 660 were excluded for being non-applicable. We assessed 23 full text articles for eligibility and all of these studies were excluded from the review.

AUTHORS' CONCLUSIONS

We were unable to identify any RCTs or CCTs assessing the efficacy and safety of intra-masseteric injections of botulinum toxin for people with bilateral benign masseter hypertrophy. The absence of high level evidence for the effectiveness of this intervention emphasises the need for well-designed, adequately powered RCTs.

Diagnosis of Zygomaticus Muscle Paralysis Using Needle Electromyography With Ultrasonography

A 22-year-old woman visited our clinic with a history of radiofrequency volumetric reduction for bilateral masseter muscles at a local medical clinic. Six days after the radiofrequency procedure, she noticed a facial asymmetry during smiling. Physical examination revealed immobility of the mouth drawing upward and laterally on the left. Routine nerve conduction studies and needle electromyography (EMG) in facial muscles did not suggest electrodiagnostic abnormalities. We assumed that the cause of facial asymmetry could be due to an injury of zygomaticus muscles, however, since defining the muscles through surface anatomy was difficult and it was not possible to identify the muscles with conventional electromyographic methods. Sono-guided needle EMG for zygomaticus muscle revealed spontaneous activities at rest and small amplitude motor unit potentials with reduced recruitment patterns on volition. Sono-guided needle EMG may be an optimal approach in focal facial nerve branch injury for the specific localization of the injury lesion.

Correction of lower facial wideness due to masseter hypertrophy

Masseter hypertrophy is an uncommon condition that can cause aesthetic and functional problems. Various treatment options were suggested by authors. We used surgical intraoral approaches in 5 patients, which consist of masseter muscle reduction and monocortical ostectomy in the angle of the mandible. Results showed good aesthetic results without any complication. We suggest the use of surgical treatment to gain optimal aesthetic results especially in a square face.

Electromyographic activity of the masseter muscle after radiofrequency therapy in an animal model

PURPOSE

The purpose of this study was to examine changes in the electromyographic (EMG) activity of the masseter muscle after radiofrequency therapy (RF).

METHODS

Twelve rabbits were used in this study: four in each group according to the number of RF applications. Preoperative EMG in the masseter muscle was used as the control. EMG was recorded at 1, 2, 3, and 4 weeks after RF in each rabbit. The recorded data were analyzed in terms of voltage and frequency, and changes in recorded variables were compared among the groups. The relative activity in peak voltage, root mean square of the action potential, area of voltage, and area of frequency were investigated.

RESULTS

When compared to preoperative values, the variables at 3 or 4 weeks after RF application were significantly different in the single and quadruple therapy groups (P<0.05). There was no significant difference in the other groups (P>0.05). When the samples were regrouped as two groups like small number of application group (one or two point) and large number of application group (three or four points), the area of voltage and the area of frequency were significantly different between the groups at 4 weeks (P<0.05).

CONCLUSIONS

Masseter muscle activity after RF was significantly decreased compared to its preoperative state. The decreased activity was related to the number of applications and time elapsed after RF.

The change in dimension of the masseter muscle in rabbits after radiofrequency therapy

PURPOSE

The objective of this study was to evaluate the change in muscle dimension after administering radiofrequency (RF) therapy.

MATERIALS AND METHODS

This study used 6 male New Zealand rabbits. Groups were divided by number of applications of RF (eg, 1 to 4 points). The dimension of the masseter muscle was measured using a computerized tomogram scan before operation, and at 1, 2, 3, and 4 weeks after RF therapy was administered under the same conditions. Two horizontal cuts were selected for measurement.

RESULTS

The size of the measured areas for each group at 1 week after RF therapy was significantly increased compared with the preoperative value (P< .05). When the measurements of each group at 3 and 4 weeks after RF therapy were compared with the preoperative value, they were significantly decreased (P< .05). The dimensional change was significantly different among groups at 1 and 3 weeks post RF therapy (P< .05). The swelling at 1 week after RF therapy was increased in terms of the number of RF applications. The ratio of dimension was decreased at 3 weeks after RF therapy in terms of the number of RF applications.

CONCLUSION

There was an increase in muscle dimension because of swelling in the early stages of RF therapy. However, this dimension decreased at 3 weeks post-RF administration compared with the preoperative value. Therefore, it can be concluded that the change in the masseter muscle dimension was dependent on the number of RF applications.

Botulinum toxin for masseter hypertrophy

BACKGROUND

Benign masseter muscle hypertrophy is an uncommon clinical phenomenon of uncertain aetiology which is characterised by a soft swelling near the angle of the mandible. The swelling may on occasion be associated with facial pain and can be prominent enough to be considered cosmetically disfiguring. Varying degrees of success have been reported for some of the treatment options for masseter hypertrophy, which range from simple pharmacotherapy to more invasive surgical reduction. Injection of botulinum toxin type A into the masseter muscle is generally considered a less invasive modality and has been advocated for cosmetic sculpting of the lower face. Botulinum toxin type A is a powerful neurotoxin which is produced by the anaerobic organism Clostridium botulinum and when injected into a muscle causes interference with the neurotransmitter mechanism producing selective paralysis and subsequent atrophy of the muscle.

OBJECTIVES

To assess the effects of botulinum toxin type A in the management of benign bilateral masseter hypertrophy.

SEARCH STRATEGY

We searched the following databases in August 2008: the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2008, issue 3); MEDLINE (via PubMed) (1950 to August 2008); EMBASE (via embase.com) (1980 to August 2008); and LILACS via BIREME. We searched two bibliographic databases of regional journals which may be expected to contain relevant trials (IndMED and Iranmedex) using free text terms appropriate for this review.

SELECTION CRITERIA

Randomised controlled clinical trials (RCTs) and controlled clinical trials (CCTs) comparing intra-masseteric injections of botulinum toxin versus placebo administered for cosmetic facial sculpting in individuals of any age with bilateral benign masseter hypertrophy, which had been self-evaluated and confirmed by clinical and radiological examination. We excluded participants with unilateral or compensatory contralateral masseter hypertrophy resulting from head and neck radiotherapy.

DATA COLLECTION AND ANALYSIS

Two review authors conducted screening of studies in duplicate and independently, and although no eligible trials were identified, the two authors had planned to extract data independently and assess trial quality using standard Cochrane Collaboration methodologies.

MAIN RESULTS

We retrieved 167 references to studies, none of which matched the inclusion criteria for this review and all of which were excluded.

AUTHORS' CONCLUSIONS

We were unable to identify any randomised controlled trials on the efficacy of intra-masseteric injections of botulinum toxin for people with bilateral benign masseter hypertrophy. The absence of high level evidence for the effectiveness of this intervention emphasises the need for well-designed, adequately powered, randomised controlled clinical trials (RCTs) and controlled clinical trials (CCTs).