Injectable and topical neurotoxins in dermatology: Indications, adverse events, and controversies

The use of neuromodulators for therapeutic and cosmetic indications has proven to be remarkably safe. While aesthetic and functional adverse events are uncommon, each anatomic region has its own set of risks of which the physician and patient must be aware before treatment. The therapeutic usages of botulinum toxins now include multiple specialties and multiple indications. New aesthetic indications have also developed, and there has been an increased utilization of combination therapies to combat the effects of global aging. In the second article in this continuing medical education series, we review the prevention and treatment of adverse events, therapeutic and novel aesthetic indications, controversies, and a brief overview of combination therapies

Injectable and topical neurotoxins in dermatology: Basic science, anatomy, and therapeutic agents

Botulinum toxin is a potentially deadly anaerobic bacterial toxin that acts by inhibiting release of acetylcholine at the neuromuscular junction, thereby inhibiting contraction of the exposed striated muscle. There are currently 4 botulinum toxin preparations approved by the US Food and Drug Administration (FDA): onabotulinumtoxin, abobotulinumtoxin, incobotulinumtoxin and rimabotulinumtoxin. While significant overlap exists, each product has unique properties and specifications, including dosing, diffusion, and storage. Extensive physician knowledge of facial anatomy, coupled with key differences of the various neurotoxin types, is essential for safe and successful treatments. The first article in this continuing medical education series reviews key characteristics of each neurotoxin, including new and upcoming agents, and provides an anatomic overview of the most commonly injected cosmetic sites

Understanding photodermatoses associated with defective DNA repair: Photosensitive syndromes without associated cancer predisposition

Photodermatoses associated with defective DNA repair are a group of photosensitive hereditary skin disorders. In this review, we focus on diseases and syndromes with defective nucleotide excision repair that are not accompanied by an increased risk of cutaneous malignancies despite having photosensitivity. Specifically, the gene mutations and transcription defects, epidemiology, and clinical features of Cockayne syndrome, cerebro-oculo-facial-skeletal syndrome, ultraviolet-sensitive syndrome, and trichothiodystrophy will be discussed. These conditions may also have other extracutaneous involvement affecting the neurologic system and growth and development. Rigorous photoprotection remains an important component of the management of these inherited DNA repair-deficiency photodermatoses

Understanding photodermatoses associated with defective DNA repair: Syndromes with cancer predisposition

Hereditary photodermatoses are a spectrum of rare photosensitive disorders that are often caused by genetic deficiency or malfunction of various components of the DNA repair pathway. This results clinically in extreme photosensitivity, with many syndromes exhibiting an increased risk of cutaneous malignancies. This review will focus specifically on the syndromes with malignant potential, including xeroderma pigmentosum, Bloom syndrome, and Rothmund-Thomson syndrome. The typical phenotypic findings of each disorder will be examined and contrasted, including noncutaneous identifiers to aid in diagnosis. The management of these patients will also be discussed. At this time, the mainstay of therapy remains strict photoprotection; however, genetic therapies are under investigation

Local Anesthesia: Evidence, Strategies, and Safety

The number of office-based procedures performed utilizing local anesthesia continues to rise, particularly in dermatologic settings. As more emphasis is placed on cost effectiveness in medicine, it is important to understand the role that office-based procedures can play in providing excellent dermatologic care. In addition, it is essential to continually demonstrate that local anesthesia administered in office-based settings is safe and effective in order to maintain a high standard of care within the specialty. Achieving adequate local anesthesia is imperative to ensure patient comfort, reduce anxiety, and promote optimal outcomes. The clinician should have a comprehensive understanding of the pathophysiology, mechanism of action, practical applications and techniques, and potential adverse events of various topical and injectable anesthetics in order to enhance patient satisfaction and safety. Lidocaine, which is the most commonly used local anesthetic, has a rapid onset, moderate duration, and excellent safety profile, making it a staple in office-based procedures

Systematic Review and Meta-Analysis of Local Recurrence Rates of Head and Neck Cutaneous Melanomas after Wide Local Excision, Mohs Micrographic Surgery, or Staged Excision

Background Prospective trials have not compared local recurrence rates for different excision techniques for cutaneous melanomas on the head and neck. Objective To determine local recurrence rates of cutaneous head and neck melanoma after wide local excision (WLE), Mohs micrographic surgery (MMS), or staged excision. Methods A systematic review of PubMed, EMBASE, and Web of Science identified all English case series, cohort studies and randomized controlled trials that reported local recurrence rates after surgery of cutaneous head and neck melanoma. A meta-analysis utilizing a random effects model calculated weighted local recurrence rates and confidence intervals (CI) for each surgical technique and for subgroups of MMS and staged excision. Results Among one-hundred manuscripts with 13,998 head and neck cutaneous melanomas, 51.0% (7138) of melanomas were treated by WLE; 34.5% (4,826) by MMS; and 14.5% (2,034) by staged excision. Local recurrence rates were lowest for MMS (0.61%; 95%CI, 0.1%-1.4%); followed by staged excision (1.8%; 95%CI, 0.1%-2.9%) and WLE (7.8%; 95%CI, 6.4%-9.3%). Limitations Definitions of local recurrence varied. Surgical techniques included varying proportions of invasive melanomas. Studies had heterogeneity. Conclusion Systematic review and meta-analysis show lower local recurrence rates for cutaneous head and neck melanoma after treatment with MMS or staged excision compared to WLE