Dose-Effect Relationship of Botulinum Toxin Type A in the Management of Strabismus: A Review.

Botulinum toxin type A (BTXA) is a well-accepted non-surgical therapy for strabismus. However, its dose and technique vary widely. We reviewed published evidence on the dose effect of BTXA in treating various types of strabismus. Articles on BTXA therapy outcomes were reviewed to study doses and brands of BTXA used and their efficacy for specific types of strabismus. Researchers indicated that greater dosages may be used safely without increasing the risk of complications. The review suggested a positive dose-response relationship of BTX to success but with a higher risk of complications. No single dose of BTX could be recommended for strabismus management.

An Ultrasonographic Analysis of the Deep Inferior Tendon in the Masseter Muscle: Implications for Botulinum Toxin Injections.

(1) Background: With the increasing aesthetic pursuit of facial features, the clinical use of Botulinum Toxin Type A (BoNT-A) injections for masseter hypertrophy has been on the rise. However, due to variations in masseter muscle structure and differences in clinicians' injection techniques, blind injections may lack precision, potentially compromising treatment accuracy and increasing the risk of complications. (2) Objectives: The study aims to use ultrasonography to detail the deep inferior tendon (DIT) within the masseter muscle in a young Chinese cohort, refine its classification, analyze muscle belly thickness and variations across groups, and propose a customized ultrasound-guided BoNT-A injection protocol. (3) Methods: Ultrasound imaging was used to observe the bilateral masseter muscles at rest and during clenching. The features of the DIT were classified from these images, and the thickness of the masseter's distinct bellies associated with the DIT types was measured in both states. (4) Results: The study cohort included 103 participants (27 male, 76 female), with 30 muscles in the normal masseter group and 176 muscles in the hypertrophy group. The DIT was categorized as Type A, B (subtypes B1, B2), and C. The distribution of these types was consistent across normal, hypertrophic, and gender groups, all following the same trend (B > A > C). In hypertrophy, Type B1 showed uniform thickness across masseter bellies, B2 presented with a thinner intermediate belly, and Type C had mainly superficial muscle enlargement. Changes in muscle thickness during clenching were noted but not statistically significant among different bellies. (5) Conclusions: The study evidences individual variation in the DIT, highlighting the importance of precise DIT classification for effective BoNT-A injections. A tailored ultrasound-guided BoNT-A injection strategy based on this classification may enhance safety and efficacy of the therapy.

The efficacy of Botulinum Toxin in Tennis Elbow: a meta-analysis of randomized clinical trials.

PURPOSE: This study aims to assess the efficacy of botulinum toxin type A (BT-A) in treating tennis elbow. METHODS: We systematically reviewed the literature and included full-text randomized clinical trials (RCTs) published until June 2024, available in PubMed, Scopus, Embase, and Cochrane CENTRAL databases. Eligible studies involved patients with tennis elbow and compared BT-A with placebo or other injectable treatments. Primary outcomes included pain relief, while secondary outcomes assessed quality of life, adverse effects, and grip strength. The risk of bias was evaluated using the Cochrane Risk of Bias tool. RESULTS: Seven RCTs with a total of 381 patients were included. The participants were predominantly middle-aged (mean age 46.64 ± 7.72 years) and diagnosed with chronic tennis elbow. BT-A doses ranged from 20U to 60U. Compared to placebo, BT-A effectively reduced pain at two to four weeks (MD = -1.37; 95% CI = -2.18 to -0.57) and at eight to 12 weeks (MD = -1.13; 95% CI = -1.62 to -0.65). Grip strength was comparable between the BT-A and placebo groups at both time points (2 to 4 weeks: SMD = -0.86; 95% CI -1.78 to 0.05; 8 to 12 weeks: SMD = 0.00; 95% CI = -0.95 to 0.95). CONCLUSION: This meta-analysis suggests that BT-A reduces pain in tennis elbow within two to 12 weeks compared to placebo. Findings are limited by study size, and further research is needed to confirm its efficacy and safety.

Dose-Dependent Effects of Botulinum Toxin Type A on Prevention of Postoperative Scars in Various Regions in the Body: A Prospective, Double-Blind Randomized Controlled Trial.

BACKGROUND: Botulinum toxin type A (BTXA) can improve wound healing and reduce scar formation; however, the exact dose required to prevent postoperative scarring across various anatomical sites remains unclear. This study aimed to investigate the effectiveness and optimal concentrations of BTXA for preventing postoperative scarring across various common surgical sites throughout the body. METHODS: In this prospective randomized controlled trial, 46 patients with benign skin tumors received injections of 1, 2.5, or 5 U/0.1 mL of BTXA or 0.9% saline immediately following surgical tumor excision on both sides of the incisions. Follow-ups were conducted at 7 days, 15 days, and 1, 3, and 6 months postoperatively. Patient-reported adverse events and standardized digital photographs were collected. Scar formation was assessed using the modified Stony Brook Scar Evaluation Scale (mSBSES). RESULTS: All 46 patients completed the trial without severe complications. The mSBSES scores were higher in the experimental groups at all follow-ups. The 5 U/0.1 mL BTXA dose group demonstrated optimal scar prevention at all high-risk sites for scar hyperplasia. No significant difference was observed between the 2.5 U/0.1 mL and 5 U/0.1 mL doses for intermediate-risk sites, while 1 U/0.1 mL dose was sufficient for low-risk sites. Overall, 86.5% of patients were satisfied with their treatments, with 16.3% being very satisfied. CONCLUSIONS: Early postoperative BTXA injection can reduce or prevent hypertrophic scarring, with optimal doses ranging from 1 to 5 U/0.1 mL depending on the surgical site, supporting broader clinical application of BTXA. The effectiveness of different concentrations of botulinum toxin type A (BTXA) in preventing postoperative scarring was compared, expanding the scope of previous research, which focused only on the head, face, and neck regions, to include the trunk and extremity areas. Different optimal injection strategies were determined based on different surgical sites and their risks of developing hypertrophic scars. The study demonstrates that BTXA not only reduces scar formation but also enhances patient satisfaction and reduces postoperative itching and pain, contributing to overall better postoperative outcomes. By establishing the efficacy and optimal dosing of BTXA for various surgical sites, this research supports the potential for broader clinical application of BTXA in aesthetic and reconstructive surgeries. LEVEL OF EVIDENCE I: 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 .

Botulinum toxin type A for treating chronic low back pain: A double blinded randomized control study.

BACKGROUND: Low back pain (LBP) is a prevalent issue that orthopedic surgeons frequently address in the outpatient setting. LBP can arise from various causes, with stiffness in the paraspinal muscles being a notable contributor. The administration of Botulinum toxin type A (BoNT-A) has been found to alleviate back pain by relaxing these stiff muscles. While BoNT-A is approved for use in numerous conditions, a limited number of randomized clinical trials (RCTs) validate its efficacy specifically for treating LBP. AIM: To study the safety and the efficacy of BoNT-A in minimizing pain and improving functional outcomes in patients of chronic LBP (CLBP). METHODS: In this RCT, adults aged 18-60 years with mechanical LBP persisting for at least six months were enrolled. Participants were allocated to either the Drug group, receiving 200 Ipsen Units (2 mL) of BoNT-A, or the Control group, which received a 2 mL placebo. Over a 2-month follow-up period, both groups were assessed using the Visual Analog Scale (VAS) for pain intensity and the Oswestry Disability Index (ODI) for disability at the start and conclusion of the study. A decrease in pain by 50% was deemed clinically significant. RESULTS: The study followed 40 patients for two months, with 20 in each group. A clinically significant reduction in pain was observed in 36 participants. There was a statistically significant decrease in both VAS and ODI scores in the groups at the end of two months. Nonetheless, when comparing the mean score changes, only the reduction in ODI scores (15 in the placebo group vs 16.5 in the drug group, clinically insignificant) was statistically significant (P = 0.012), whereas the change in mean VAS scores was not significant (P = 0.45). CONCLUSION: The study concludes that BoNT-A does not offer a short-term advantage over placebo in reducing pain or improving LBP scores in CLBP patients.

Effectiveness and safety of botulinum toxin type A combined with blepharoplasty in treating sagging skin around the eyes.

Objective: Researchers looked into the safety and effectiveness of blepharoplasty in conjunction with botulinum toxin type A for the treatment of periocular skin laxity. Methods: 92 patients who received treatment at our institution for periocular skin laxity were chosen as research subjects. Their admission time ranged from May 2020 to December 2022. Using various therapy modalities, the patients were split into two groups: an observational team (n = 46) and a controlling team (n = 46). They were respectively given blepharoplasty treatment intervention and botulinum toxin type A combined with blepharoplasty treatment intervention. Eyelid bags, crow's feet, skin radiance and aesthetic results, quality of life were analyzed before and after the intervention, and physician and patient' satisfaction with the results were compared. Results: 95.65 % was the effective rate of the observed group, which was 71.74 % compared with the control group, and significantly increased (P < 0.05). After interference, the score, aesthetic effect and quality of life grade of skin gloss, crow's feet and eyelid bags were significantly higher in the observation group than in the control group (P < 0.05). The complication rate in the observation group was 6.52 % was significantly higher than 30.43 % in the control group (P < 0.05). The patient satisfaction of the observation group was 93.48 %, significantly greater than the control group 69.57 % (P < 0.05); the customer satisfaction of the observation group was 95.65 %, which was significantly higher than the control group 82.61 % (P < 0.05). Conclusion: The combination of type A botulinum toxin and eye bag plastic surgery has a good effect on improving skin laxity around the eyes. It can significantly reduce eyelid bags and crow's feet, improve skin gloss, increase aesthetic effects, and comprehensively restore vitality to aged eye skin, improve life quality, and have high doctor-client contentment and safety.

[Five-year follow-up after neurosurgery complicated by facial neuropathy]. / Rezul'taty pyatiletnego nablyudeniya za patsientami s neiropatiei litsevogo nerva posle neirokhirurgicheskikh vmeshatel'stv.

BACKGROUND: Botulinum toxin A (BTA) injections are effective for facial neuropathy. However, there is insufficient number of studies devoted to long-term management of these patients. OBJECTIVE: To evaluate the effectiveness and safety of BTA therapy in patients with facial neuropathy after neurosurgical interventions. MATERIAL AND METHODS: The study included 86 patients with facial neuropathy after surgical treatment of posterior cranial fossa and cerebellopontine angle tumors. All ones were divided into 2 groups: group I (main) - 57 patients with BTA prescribed early after facial nerve injury, group II (control) - 29 people undergoing exercise therapy, as well as special exercises and acupressure of painful muscle cords. The Sunnybrook Facial Grading Scale (SFGS) was used to assess facial symmetry and synkinesis, the Facial Disability Index (FDI scale) - to assess the quality of life. Overall duration of the study was 5 years (control points: 6 months, 1, 2, 3 and 5 years). RESULTS: The SFGS scores after 1, 2, 3 and 5 years were significantly better in the main group (resting symmetry p<0.01, voluntary movement symmetry p<0.01, synkinesis p<0.01, general condition of facial muscles p<0.01). Scores of physical and social functioning were significantly higher in the main group after 1 (p<0.01), 2 (p<0.01), 3 (p<0.01) and 5 years (p<0.01) after surgery. There was no need to change BTA dosage over 5 years. Thus, this form of BTA may be the most effective for synkinesis of facial muscles. CONCLUSION: Correction of synkinesis caused by facial neuropathy requires long-term follow-up and long-term treatment. BTA is effective and may be recommended for long-term treatment of these patients.

Dose and injection site of botulinum toxin type A for gummy smile management: A systematic review and bibliometric analysis.

INTRODUCTION: Botulinum toxin type A (BoNT/A) is an effective non-surgical method for treating gummy smile (GS). This systematic review evaluated the efficacy, duration, and safety of different BoNT/A injections. METHODS: Four electronic databases were searched for relevant literature, generating 1106 references. RESULTS: The review included 13 prospective, controlled clinical trials. The mean pre-injection anterior gingival exposure ranged from 3.5 mm to 6.8 mm, reaching maximum effect at 2-4 weeks post-injection. Most studies indicated complete improvement in gingival exposure post-injection, with gingival exposure reduced to ≤3 mm. The dosage of BoNT/A was determined by the severity of gingival exposure, with effects lasting up to 12-24 weeks. Levator labii superioris alaeque nasi (LLSAN), levator labii superioris (LLS), and zygomaticus minor (ZMi) were the main targeted muscles. Next, bibliometric analysis was conducted to provide an overview of the existing publications on managing gummy smiles. CONCLUSIONS: This data demonstrates that BoNT/A can effectively treat various types of GS triggered by muscle hyperactivity. It is a non-intrusive treatment with significant improvement, high safety, minimal side effects, and high patient satisfaction. This study was preregistered in the Prospective Register of Systematic Reviews (CRD42024509183). CLINICAL SIGNIFICANCE: This study systematically reviewed and compared previous results on efficacy, duration, patient satisfaction, and adverse effects of different botulinum toxin type A doses and injection sites, laying a solid foundation for further studies that use BoNT/A in the management of gummy smiles.

Efficacy of Botulinum Type A Injection for the Treatment of Postherpetic Neuralgia and Pruritus Persisting for More Than Four Years-A Case Report.

Background: Postherpetic neuralgia (PHN) and postherpetic pruritus (PHP) are common complications of shingles that affect patients' quality of life. PHN and PHP can be managed using various medications and interventional procedures; however, complications persisting for at least six months may hamper recovery. Subcutaneous injections of botulinum toxin type A (BTX-A) can control persistent PHN and PHP. Case presentation: A 71-year-old man presented at our hospital with itching and pain. He had been diagnosed with shingles in the ophthalmic branch of the trigeminal nerve one year previously. As the pain and itching persisted despite medication, a supraorbital nerve block, Gasserian ganglion block, epidural nerve block, and radiofrequency thermocoagulation were performed. A subcutaneous injection of BTX-A was administered into the ophthalmic area of the trigeminal nerve three years after the initial presentation. A decrease of >80% in pain and itching was reported after the injection; however, the left eyelid drooped and the eyeball shifted downward and outward immediately after the injection. No deterioration in vision or pupil dilation was observed, and almost complete resolution of these symptoms occurred spontaneously three months after the injection. Pain and itching continued to improve without further side-effects until six months after the injection. Conclusions: The subcutaneous injection of BTX-A may be an alternative treatment option for chronic and refractory neurological diseases such as PHN and PHP, which persist for four years and are resistant to conventional treatments. Nevertheless, care must be taken to minimize the risk of ptosis.

The Effects of Botulinum Toxin Type A on the Biological Behavior of Fibroblasts on Silicone Implants.

BACKGROUND: Capsular contracture is one of the most severe complications following breast augmentation surgery. It has been reported that botulinum toxin Type A (BTX-A) can inhibit capsular contracture, but the exact mechanisms remain unclear. Therefore, this study aims to explore the potential mechanisms behind BTX-A's inhibition of capsular contracture by observing its effects on the biological behavior of fibroblasts and its impact on the TGF-ß/Smad signaling pathway. METHODS: In vitro experiments involved culturing fibroblasts on PDMS surfaces, subsequently treating them with various concentrations of BTX-A. Fibroblast proliferation activity was assessed using the CCK-8 assay, while the migration and cytoskeletal morphology of the fibroblasts were meticulously examined. ELISA was utilized to quantify the expression of fibrosis-related cytokines. Gene and protein expressions related to the TGF-ß/Smad pathway were analyzed through real-time PCR and Western blotting techniques. RESULTS: BTX-A moderately enhanced the early proliferation and migration of fibroblasts on the surface of PDMS silicone sheets and reduced the synthesis of collagen types I and III. Furthermore, under the influence of BTX-A, the expression of TGF-ßR2 and α-SMA in the TGF-ß/Smad pathway was significantly inhibited. CONCLUSIONS: This study demonstrates that BTX-A can inhibit fibroblast differentiation by downregulating the expression of TGF-ßR2, thereby suppressing the TGF-ß/Smad pathway. This suggests a possible mechanism through which BTX-A mitigates capsular contracture. NO LEVEL ASSIGNED: This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. 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 .

A preliminary study on ultrasound techniques applied to evaluate the curative effect of botulinum toxin type a in hypertrophic scars.

Objective: To validate the feasibility of ultrasound in assessing the curative effect of botulinum toxin type A (BTXA) in treating hypertrophic scar (HS). Methods: Eight healthy New Zealand long-eared rabbits were utilized in the study. Four wounds, each measuring 1.0 cm in diameter, were created on both ears of each rabbit. Immediately after surgery, each of these wounds received an injection containing a distinct concentration of BTXA. On postoperative week 6, scar thickness, vascularity, and hardness were assessed based on high frequency ultrasound (HFUS), superb microvascular imaging (SMI), shear wave elastography (SWE), Masson staining, and immunohistochemical staining for CD31. Results: All wounds healed well, and HSs formed after 6 weeks post-surgery. Scar thickness based on HFUS presented a significant decrease with increasing BTXA concentration (p < 0.05), aligning with the gross morphology. Simultaneously, scar stiffness, evaluated using SWE, showed a significant decrease in accordance with the variation of the collagen volume fraction, which refers to the ratio of the collagen positive area to the total area (p < 0.05). Although the vascularity index obtained by SMI did not exhibit a statistically significant change across different BTXA concentrations, this technique effectively illustrated the microvascular perfusion in HS. Immunohistochemical staining for CD31 revealed that BTXA inhibited angiogenesis. Conclusion: HFUS and SWE displayed excellent performance in evaluating HS thickness and stiffness. SMI showed a good performance in reflecting microvascular signals in HS. These ultrasound techniques have great potential in assessing the therapeutic effect of BTXA in HS.

Open label experience of repeated OnabotulinumtoxinA injections towards the sphenopalatine ganglion in patients with chronic cluster headache and chronic migraine.

BACKGROUND: A novel technique for injection of OnabotulinumtoxinA (BTA) towards the sphenopalatine ganglion (SPG) has shown promise in refractory chronic migraine (CM) and chronic cluster headache (CCH). Open label safety and efficacy data are presented here. METHODS: Patients with refractory CM or CCH who had received at least one injection and completed headache diaries were included. Efficacy was defined as ≥50% reduction in moderate-to-severe headache days for CM, or ≥50% reduction in attack frequency for CCH, at weeks five to eight. RESULTS: Over 261 injections, there were 123 adverse events (AE), of which one was serious. Most (93%) AEs were mild and all were transient. The 50% response to one injection was 81% for CM and 69% for CCH. The response gradually reduced over subsequent months for CM but stayed between 55% and 67% for CCH. Repeated injections were beneficial. CONCLUSIONS: Injections resulted in improvement for both groups and was maintained with repeated injections. Repeat injection after three months may be beneficial in CM. Adverse events were not uncommon, but universally transient, presumably as a result of the mechanism of action of BTA. Repeated BTA injection towards the SPG could be an effective treatment for refractory CM and CCH. Larger, randomised, placebo-controlled trials are required.

Assessing the efficacy and quality of Life improvements of botulinum toxin type a with topical minoxidil versus topical minoxidil in male androgenetic alopecia: a randomized controlled trial.

Androgenetic alopecia (AGA) is a common type of hair loss in men and efficacy and safety of current medical treatment remain limited. Therefore, the present study aimed to investigate the efficacy and safety of botulinum toxin type A (BTA) combined with Minoxidil in patients with AGA. 60 male patients were included in this study and control group received topical 5% Minoxidil and the treatment group received BTA combined with topical 5% Minoxidil. BTA injections (60-70 U) were administered at 30-35 scalp sites. Head photographs were taken at baseline, 2nd, 4th, and 6th months. Clinical descriptions recorded scalp conditions, and patient satisfaction along with Dermatology Life Quality Index scores were documented. The treatment group (TG) showed significant hair growth differences compared to the control group (CG) at the 4th month (P < 0.001) and 6th month (P = 0.0046) post-treatment. TG had improved Investigator Global Assessment (IGA) scores in the 4th month (P = 0.0001) and 6th month (P = 0.0259) compared to CG. Patient satisfaction in TG for hair growth and scalp improvement was higher than CG (all P < 0.05). TG exhibited substantial quality of life improvement at the 4-month (P = 0.0009) and 6-month (P = 0.0099). No adverse reactions were observed post-botulinum toxin injection. BTA combined with Minoxidil effectively promotes hair growth, enhances the quality of life, and alleviates scalp symptoms in male AGA patients at 4th and 6th months, with no adverse effects compared to Minoxidil alone.Trial registration number: Ethics Committee of Shanghai Tongji Hospital (ID: K-2018-026).

Exploring the Biomarkers and Potential Mechanisms of Botulinum Toxin Type A in the Treatment of Microglial Inflammatory Activation through P2X7 Receptors based on Transcriptome Sequencing.

AIMS: This study aims to explore the potential mechanism by which Botulinum toxin type A (BoNT/ A) inhibits microglial inflammatory activation through P2X7 receptors (P2X7R). BACKGROUND: BoNT/A is a promising analgesic drug, and previous studies have established that it alleviates Neuropathic Pain (NP) by inhibiting microglial inflammatory activation. This study examined the biomarkers and potential mechanisms by which BoNT/A relieves neuropathic pain by mediating microglial P2X7R and analyzing transcriptome sequencing data from mouse BV-2 microglial cells. OBJECTIVE: The P2X7R agonist Bz-ATP was used to induce microglial inflammatory activation, whilst RNAseq technology was used to explore the biomarkers and potential mechanisms through which BoNT/A suppresses microglial inflammation. METHODS: RNA sequencing was performed on three BV-2 cell samples treated with a P2X7R specific activator (Bz-ATP) and three BV-2 cell samples pre-treated with BoNT/A. Only data that successfully passed quality control measures were included in subsequent analysis. Initially, Differentially Expressed Genes (DEGs) were identified from BoNT/A and control samples, followed by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses. Biomarkers were then identified by constructing a Protein- Protein Interaction (PPI) network and utilizing the CytoHubba plug-in in Cytoscape software. Lastly, enrichment analysis and regulatory network analysis were performed to elucidate the potential mechanism of BoNT/A in the treatment of NP. RESULTS: 93 DEGs related to the "cell component size regulation" GO term and enriched in the "axon guidance" KEGG pathway were identified. Subsequently, 6 biomarkers were identified, namely PTPRF, CHDH, CKM, Ky, Sema3b, and Sema3f, which were enriched in pathways related to biosynthesis and metabolism, disease progression, signal transduction, and organelle function, including the "ribosome" and "Wnt signaling pathway." Finally, a competing endogenous RNA (ceRNAs) network was constructed from 6 mRNAs, 66 miRNAs, and 31 lncRNAs, forming a complex relationship network. CONCLUSION: Six genes (PTPRF, Sema3b, Sema3f, CHDH, CKM, and Ky) were identified as biomarkers of microglial inflammatory activation following BoNT/A treatment. This finding may provide a valuable reference for the relief and treatment of neuropathic pain.

Botulinum Toxin Type A and Hyaluronic Acid Dermal Fillers in Dentistry: A Systematic Review of Clinical Application and Indications.

Background: Botulinum toxin type A (BoNT-A) and hyaluronic acid (HA) dermal fillers are increasingly utilized in dentistry for therapeutic and aesthetic purposes. However, a comprehensive synthesis of their clinical applications and indications in dentistry is lacking. This systematic review aimed to analyze the clinical application and indications of BoNT-A and HA dermal fillers in dentistry, providing insights into their efficacy, safety profiles, and limitations. Methods: A systematic search was conducted in PubMed/MEDLINE databases to identify relevant studies published between 2018 and 2024. Medical Subject Headings (MeSH) terms and keywords related to BoNT-A, HA dermal fillers, dentistry, clinical applications, and indications were used. Study selection criteria included randomized controlled trials (RCTs) and non-RCTs involving human participants of any age group. Data extraction and synthesis followed established guidelines, focusing on study characteristics, participant demographics, intervention details, outcome measures, and key findings related to BoNT-A and HA dermal fillers' clinical application in dentistry. Results: Systematic searches across electronic databases and grey literature identified 857 records, with an additional 73 from hand searches. After screening titles and abstracts, 542 records were excluded, leaving 374 full-text publications for evaluation. Ultimately, 12 RCTs and 13 non-RCTs were included. The systematic review encompassed diverse geographic locations: Brazil, Italy, Spain, Syria, India, Egypt, Korea, and the Netherlands, involving samples sizes ranging from 14 to 143 participants. The review synthesized findings on HA's efficacy in various areas, including bone repair, gingivitis management, temporomandibular joint disorders, postoperative swelling reduction, periodontal defect treatment, chin and check projection and lips augmentation. BoNT-A exhibited promising efficacy in managing orofacial pain conditions, gummy smile treatment and neuromodulation of the lower third muscles. Safety profiles varied among studies, with some reporting minimal adverse effects while others noted dose-related concerns. Conclusion: BoNT-A and HA dermal fillers offer a wide array of clinical applications in dentistry, ranging from therapeutic interventions to aesthetic enhancements. Despite promising efficacy, careful consideration and monitoring of safety outcomes are essential when integrating these interventions into clinical practice. Further research addressing methodological limitations and safety concerns is warranted to optimize their utilization and improve patient care in dentistry.

Application of botulinum toxin in the repair of a complex ventral hernia. / Aplicación de toxina botulínica en la reparación de una hernia ventral compleja.

INTRODUCTION: Preoperative application of botulinum toxin type A has demonstrated to be safe and effective in the closure of complex ventral hernias in adults. However, its use in pediatrics has been little documented. CASE REPORT: We present the case of a 22-month-old girl with a complex abdominal wall ventral hernia secondary to multiple neonatal laparotomies. In a first procedure, botulinum toxin was administered using an intramuscular approach at six sites of the muscle layers surrounding the defect, under general anesthesia and ultrasound control. 4 weeks later, an open hernia repair was conducted, without complications. DISCUSSION: Botulinum toxin at low doses could facilitate the surgical treatment of complex ventral incisional hernias in children. Even though it is important to adjust dosage and anatomical reference points according to hernia type and patient age and weight, further studies are required to optimize these variables.

INTRODUCCION: La aplicación preoperatoria de toxina botulínica A ha demostrado ser segura y efectiva en el cierre de hernias ventrales complejas en adultos. Sin embargo, se ha documentado poco su uso en pediatría. CASO CLINICO: Se presenta el caso de una niña de 22 meses con una hernia de pared abdominal ventral compleja secundaria a múltiples laparotomías neonatales. En una primera intervención se administró por vía intramuscular toxina botulínica en seis puntos de las capas musculares alrededor del defecto bajo anestesia general y control ecográfico. Cuatro semanas después, se realizó una reparación abierta de la hernia, sin complicaciones. COMENTARIOS: La toxina botulínica a dosis bajas podría facilitar el tratamiento quirúrgico de hernias incisionales ventrales complejas en niños. Es importante ajustar la dosis y los puntos de referencia anatómicos según el tipo de hernia, la edad y el peso del paciente, aunque se requieren más estudios para optimizar estas variables.

Temporary Delayed Hypersensitivity Reaction to Botulinum Toxin-A After COVID-19 Vaccination: A Case Series.

PURPOSE: The occurrence of a hypersensitivity reaction with the injection of botulinum toxin type A (BTX-A) in cosmetic use is a rare complication. We report the largest case series of temporary delayed hypersensitivity reaction (DHR) with BTX-A following COVID-19 vaccination and the first cases to incobotulinum toxin A (incoBTX-A). METHODS: A retrospective multicentric case series of patients who developed a DHR to BTX-A after COVID-19 vaccination. RESULTS: Twelve patients were treated with BTX-A injections for the management of facial rhytids. The age range was between 29 and 45 years. Ten (83.3%) were female. Ten (83.3%) patients received incoBTX-A, and two received onabotulinum toxin A (onaBTX-A). All patients had COVID-19 vaccination (mRNA vaccine) between 1 and 7 months before. Within an average time of 24 h after BTX-A injection, all patients developed progressive facial swelling and erythema that were more prominent at the injection points. Intradermal allergic tests to BTX-A were performed in six (50%) patients, and the results were all negative. Adequate clinical control was achieved with systemic corticosteroids and antihistamines. After 1 year with no further vaccination, a new BTX-A treatment (provocation test) was performed in all patients with no secondary effects. CONCLUSION: Previous COVID-19 vaccination and the absence of new adverse events with further BTX-A injections suggest a temporary DHR. Clinicians should be aware of the importance of immunization history and its potential post-vaccine immunogenic effects with BTX-A. 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 .

Sustained benefits of onabotulinumtoxinA treatment in chronic migraine: An analysis of the pooled Phase 3 REsearch Evaluating Migraine Prophylaxis Therapy (PREEMPT) randomized controlled trials.

OBJECTIVE: To characterize the long-term (56-week) benefits of continuous onabotulinumtoxinA treatment response in individuals with chronic migraine (CM) who achieved reduction to <15 headache days/month with treatment. BACKGROUND: There are limited data exploring reductions in monthly headache days to levels consistent with episodic migraine among those experiencing CM. Understanding the impact of sustained preventive treatment response in CM can provide important information about the impact of successful therapy. METHODS: The two Phase 3 REsearch Evaluating Migraine Prophylaxis Therapy trials of onabotulinumtoxinA in adults included a 24-week, randomized, double-blind, placebo-controlled phase and a 32-week open-label phase. Data were pooled to determine proportions of individuals with <15 headache days/month while on treatment during several time periods in the double-blind phase (Weeks 21-24; any 12 consecutive weeks; Weeks 13-24) and the entire study (Weeks 53-56; any 12 consecutive weeks; any 4-week period). We assessed the long-term impact on mean monthly headache days and changes from baseline on the six-item Headache Impact Test (HIT-6) and Migraine-Specific Quality of Life questionnaire version 2.1 (MSQv2.1). RESULTS: We analyzed 1384 participants with chronic migraine (double-blind: onabotulinumtoxinA, n = 688; placebo, n = 696; open-label: n = 688 [onabotulinumtoxinA]). The discontinuation rates prior to the completion of the full 56-week treatment period for onabotulinumtoxinA and placebo were 25.4% (n = 175) and 29.3% (n = 204), respectively. During Weeks 13-24 of the double-blind phase, significantly more onabotulinumtoxinA-treated (386/688 [56.1%]) than placebo-treated (342/696 [49.1%]) individuals had <15 headache days/month (p = 0.010), with fewer monthly headache days for onabotulinumtoxinA versus placebo responders. The proportions of participants achieving <15 monthly headache days with onabotulinumtoxinA were 60.9% (419/688) at Weeks 25-56, 81.1% (558/688) at Weeks 53-56, and 79.4% (546/688) during any consecutive 12-week period. Mean changes from baseline on the HIT-6 and MSQv2.1 questionnaire surpassed within-group minimal important difference thresholds in all periods. At Week 24, onabotulinumtoxinA-treated participants who achieved <15 monthly headache days during Weeks 21-24 had a greater mean HIT-6 score reduction (-6.5 vs. -1.4) and greater mean MSQv2.1 Role-Function Restrictive score improvements (21.3 vs. 6.4) than those who did not achieve <15 monthly headache days during the same period. CONCLUSIONS: Participants who achieved <15 monthly headache days with onabotulinumtoxinA treatment achieved meaningful benefits in headache-related disability and migraine-specific quality of life compared with those who remained at or above the 15-monthly headache days threshold. Sustained benefits observed over 56 weeks support long-term onabotulinumtoxinA use for the prevention of CM.

Gait analysis using three-dimensional motion and ground reaction force systems in patients with hemiplegia treated with botulinum toxin type A in ankle plantar flexors.

Objective: The efficacy of botulinum toxin type A (BoNT-A) injection on spasticity has usually been measured using the range of motion (ROM) of joints and Modified Ashworth Scale (MAS); however, they only evaluate muscle tone at rest. We objectively analyzed the gait of three patients with hemiplegia using three-dimensional motion analysis and ground reaction force (GRF) systems to evaluate muscle tone during gait. Materials and Methods: We measured passive ankle dorsiflexion ROM with knee extension and the MAS score for clinical evaluation, and gait speed, stride length, single-leg support phase during the gait cycle, joint angle, joint moment, and GRFs for kinematic evaluation before and one month after BoNT-A injection. Results: All patients showed an increase in ankle dorsiflexion ROM, improvement in MAS score, and increase in stride length. Case 1 showed an increase in gait speed, prolongation of the single-leg support phase, increase in hip extension angle and moment, and improvement in the vertical and anterior-posterior components of the GRFs. Case 2 showed an increase in gait speed, improvement in double knee action, increase in ankle plantar flexion moment, and improvement in propulsion in the progressive component of the GRFs. Case 3 exhibited a laterally directed force in the GRFs. Conclusion: We evaluated the effects of BoNT-A injections in three patients with hemiplegia using three-dimensional motion analysis and GRFs. The results of the gait analysis clarified the improvements and problems in hemiplegic gait and enabled objective explanations for patients.

Clinical benefit of botulinum toxin for treatment of persistent TMD-related myofascial pain: A randomized, placebo-controlled, cross-over trial.

BACKGROUND: Injections of botulinum toxin type A (BoNT-A) have been proposed as an additional treatment modality for patients suffering chronic temporomandibular disorder (TMD)-related myofascial pain (MFP). BoNT-A impairs muscle function, along with its analgesic effect, and a minimal effective dose should be used. The objective of this randomized placebo-controlled crossover study was to evaluate the clinical benefit of a moderate dose (50 U) of BoNT-A. METHODS: Sixty-six subjects were randomized into two groups, one which received BoNT-A first and a second which received a saline solution (SS) first. Follow-ups were performed 2, 11, and 16 weeks after the injections. Diagnostic criteria for temporomandibular disorders (DC/TMD) diagnostic algorithms were used to evaluate characteristic pain intensity (CPI) and pain-related disability based on the Graded Chronic Pain Scale (GCPS). Electromyographic and bite force were also evaluated. RESULTS: The within-group analysis showed a significant improvement in pain intensity and pain-related disability after BoNT-A (p < 0.001, p = 0.005, p = 0.011) and SS (p = 0.003, p = 0.005, p = 0.046) injections up to week 16. The between-group analysis of pain-related variables revealed no differences between groups at any time. Nonetheless, BoNT-A, but not SS, caused a significant decline in muscle performance. The number needed to treat (NNT) regarding a clinically significant pain reduction (≥30%) was 6.3, 57.0, and 19.0 at 2, 11, and 16-week follow-ups favoring BoNT-A. CONCLUSIONS: Injections of 50 U of BoNT-A might improve MFP symptoms, but the specific effect of the drug on pain compared to the placebo is not obvious.