Poiseuille's law and large-bore needles: Insights into the delivery of corticosteroid injections in the treatment of keloids

A structured approach with Swiss cheese model to reduce vascular adverse events of filler injections

BACKGROUND

Filler injection is among the most popular nonsurgical aesthetic procedures worldwide. Though relatively noninvasive, filler injection can lead to severe vascular adverse events. Even though the incidence is rare, it may cause devastating and irreversible outcomes. A Swiss cheese model has been widely applied for risk analysis and management approach in medical field.

AIMS

In this review article, we adopt the Swiss cheese model and create a structured approach to prevent severe vascular complications caused by filler injections.

METHODS

We reviewed the current literature regarding the knowledge and techniques of preventing vascular adverse events in the filler injection.

RESULTS

We propose four structured strategies in this model to reduce the risk of severe vascular adverse events of filler injections, including clinical facial anatomy, safe filler injection principles, real time imaging and auxiliary instruments, and implication of checklist.

CONCLUSION

This review provides clinicians a structured approach before and during the filler injection procedure to reduce the risk of vascular adverse events and improve its safety and outcome.

Topical Anesthetic versus Lidocaine Mixture for Pain Relief During Keloid Treatment: A Prospective, Split Study

BACKGROUND

The most common typical symptoms of keloids can be pain and itchiness. Intralesional corticosteroid administration is generally the first-line conservative treatment. Minimizing pain during intralesional corticosteroid injections into keloids should be aimed, as the treatment is often painful. There has yet to be a report on which local anesthetic technique is superior in keloid treatment between topical anesthetic versus lidocaine mixture injection.

METHODS

This was a single-center prospective study. The study included 100 patients with painful multiple/multifocal keloids aged 18 to 85 years and was performed between May 2021 and December 2022. Among multiple keloid lesions in a single patient, we assigned the keloids pretreated with topical cream application versus local injection. Then, subjects received 40 mg of intralesional corticosteroid injections into the keloids with a 26G needle to treat keloids. Patients rated the pain intensity of each lesion pretreated with two different anesthetic techniques on an 11-point numeric rating scale. A separate direct question of "Which technique would you recommend if you had to be injected again?" was given.

RESULTS

One-hundred patients with painful multiple/multifocal keloids were included in the study. Data on pain intensity numeric rating scale (NRS) revealed that injection techniques relieved the pain statistically significantly more than topical creams. ( P <0.001) 63% of the participants (n=63) preferred the injection technique, while 25% preferred topical anesthetics. In total, 12% of patients responded that there was no difference between the two techniques.

CONCLUSION

When comparing with topical lidocaine/prilocaine (EMLA) cream, a 1:1 mixture of 1% lidocaine and epinephrine significantly alleviated pain during and after the corticosteroid injection.

Revisiting the Role of Local Cryotherapy for Acne Treatment: A Review and Update

Acne vulgaris is a well-recognized condition among adolescents and adults that adversely affects their quality of life. Local cryotherapy has long been reported to be effective in treating acne vulgaris, inducing a more rapid involution of acne than topical medications. However, the use of cryotherapy has been limited for acne treatment due to several drawbacks, including procedural pain and pigmentary alterations. Currently, newer cryotherapy devices are gaining attention in dermatology due to their ability to monitor and precisely control the target temperature. In this narrative review, a brief history and the latest update on acne cryotherapy will be presented. Additionally, a special emphasis is placed on the role of cryotherapy, alone or in combination with intralesional steroid injections for nodulocystic acne.

Botulinum toxin type a intralesional monotherapy for treating human hypertrophic scar in a dose-dependent manner: In an animal model

BACKGROUND

The effect of Botulinum toxin type A (BTX-A) in treating or preventing a hypertrophic scar (HS) had been reported in clinical studies. However, the dose-effect relationship remains unclear.

OBJECTIVE

To study the dose-effect relationship of BTX-A intralesional monotherapy treating human HS.

METHODS

Six HS tissues were collected from six patients. Each tissue was segmented into 24 specimens and split into four groups: negative control (group A), 0.5U BTX-A (group B), 1U BTX-A (group C), and 2U BTX-A (group D). Six nude mice, each was prepared by implanting four specimens (one from each group) into the back for a total of 24 specimens. The process mentioned above were repeated six times. A re-entry operation was performed to obtain the specimens after 8 weeks. The weight of HS, the expression of decorin and TGF-β₁, the proliferation, and migration ability of hypertrophic scar fibroblasts (HSFBs) were compared among groups.

RESULTS

The weight of HS, the expression of decorin and TGF-β₁, the proliferation, and migration ability of HSFBs showed significant differences in groups C and D as compared to group A; there has been no statistical significance in group B.

CONCLUSION

BTX-A showed significant therapeutic efficacy when compared with the negative control group in a dose-dependent manner. BTX-A can reduce the weight of HS, upregulate the expression of decorin, downregulate the expression of TGF-β₁, and inhibit HSFBs proliferation and migration ability. This study indicates that BTX-A intralesional monotherapy treating HS should reach a threshold dose to achieve an effective treatment, and a high dose of BTX-A is more effective than a low dose.

The Scar Bane, Without the Pain: A New Approach in the Treatment of Elevated Scars: Thermomechanical Delivery of Topical Triamcinolone Acetonide and 5-Fluorouracil

Introduction

Keloids are challenging to treat due to their inadequate response to treatment and high recurrence rate. Intralesional triamcinolone acetonide (TAC) injection with or without 5-fluorouracil (5FU) is considered the first-line treatment for keloids. Three significant disadvantages of intralesional injections are the pain associated with the procedure, the uneven topography, and epidermal atrophy. Fractionated ablative carbon dioxide (CO₂) laser-assisted drug delivery (LADD) of the topical solution can help facilitate transdermal drug delivery and shows promise in scar remodeling. This study examined the use of a thermomechanical device (Tixel, Novoxel) to facilitate the transdermal delivery of TAC and 5-FU in the treatment of keloid scars.

Methods

Seven patients each received eight topical thermal ablations, with one ablation performed every 2–3 weeks. TAC and 5FU were applied after each ablation. Outcomes were evaluated using the Vancouver Scar Scale (VSS), and pain was assessed using the Visual Analog Scale (VAS).

Results

Mean keloid VSS reduced from 8.6 ± 1.2 to 5 ± 2.7 after the eight treatments. Mean treatment pain VAS score was 2.4 ± 0.7. Patients rated their satisfaction level as moderate–high. No severe adverse reactions were noted.

Conclusion

Thermomechanical drug delivery of TAC and 5-FU is safe and effective. This is a promising option for the treatment of keloid scars, particularly in the pediatric population.

The fortune cookie flap for aesthetic reconstruction after chest keloid resection: a small case series

Background

Generally, the recurrence rate of keloids is unacceptably high after surgical excision alone. Nevertheless, surgical reduction of keloids is inevitable in many cases. The reconstruction of extensive soft tissue defects following complete keloid resection is challenging to surgeons. In this study, we present our clinical experience using a novel fortune cookie flap for treating chest keloids. This flap provides an excellent surgical option that maintains natural appearance with minimal donor-site morbidity.

Methods

We retrospectively reviewed the data from 3 consecutive cases of reconstruction using the fortune cookie flap following resection of chest keloids between March and December, 2017.

Results

Successful reconstructions were performed without any major complications. The mean dimensions of the reconstructed defect were 5.0 × 4.2 cm, while the mean dimensions of the flap were 7.7 × 5.7 cm.

Conclusions

Owing to its simplicity, reliability, versatility, minimal morbidity and excellent aesthetics, the fortune cookie flap is as an excellent option for reconstruction following complete keloid resection on the chest.

Electronic supplementary material

The online version of this article (10.1186/s13019-018-0713-x) contains supplementary material, which is available to authorized users.

A Topical Anesthetic and Lidocaine Mixture for Pain Relief During Keloid Treatment: A Double-Blind, Randomized Controlled Trial

BACKGROUND

Keloids are abnormal overgrowth of collagen fibers, and the first-line treatment includes intralesional injection of triamcinolone acetonide (TA), which is associated with pain.

OBJECTIVE

To study the benefit of applying topical anesthetics or a 1:1 mixture of 1% lidocaine and TA at the TA injection site to alleviate pain during keloid treatment.

METHODS AND MATERIALS

A double-blind, randomized controlled trial was conducted. Four TA injection methods were tested: control, lidocaine, topical, and combined. A visual analog scale (VAS) was used to assess needle-stick and injection pain. Data on pain duration after injection were also collected.

RESULTS

Forty patients were enrolled (mean age, 37.1 years). The VAS scores of needle-stick pain in the control, lidocaine, topical, and combined groups were 4.18 ± 2.12, 3.82 ± 2.48, 2.03 ± 2.02, and 2.20 ± 1.99, respectively. Pain statistically decreased in the topical and combined groups. Intralesional injection pain (VAS) scores in the control, lidocaine, topical, and combined groups were similar as follows: 4.97 ± 2.50, 4.97 ± 2.79, 4.10 ± 2.80, and 4.43 ± 2.68, respectively.

CONCLUSION

Application of topical anesthetics significantly relieved needle-stick pain, especially at sternum and auricular keloids; administration of a lidocaine mixture did not alleviate pain during injection.

Airway Microbial Community Turnover Differs by BPD Severity in Ventilated Preterm Infants

Preterm birth exposes the developing lung to an environment with direct exposure to bacteria, often facilitated by endotracheal intubation. Despite evidence linking bacterial infections to the pathogenesis of bronchopulmonary dysplasia (BPD), systematic studies of airway microbiota are limited. The objective was to identify specific patterns of the early respiratory tract microbiome from tracheal aspirates of mechanically ventilated preterm infants that are associated with the development and severity of BPD. Infants with gestational age ≤34 weeks, and birth weight 500-1250g were prospectively enrolled. Mechanically ventilated infants had tracheal aspirate samples collected at enrollment, 7, 14, and 21 days of age. BPD was determined by modified NIH criteria with oxygen reduction tests; infants without BPD were excluded due to low numbers. Aspirates were processed for bacterial identification by 16S rRNA sequencing, and bacterial load by qPCR. Cross-sectional analysis was performed using 7 day samples and longitudinal analysis was performed from subjects with at least 2 aspirates. Microbiome analysis was performed on tracheal aspirates from 152 infants (51, 49, and 52 with mild, moderate, and severe BPD, respectively). Seventy-nine of the infants were included in the cross-sectional analysis and 94 in the longitudinal. Shannon Diversity, bacterial load, and relative abundance of individual taxa were not strongly associated with BPD status. Longitudinal analysis revealed that preterm infants who eventually developed severe BPD exhibited greater bacterial community turnover with age, acquired less Staphylococcus in the first days after birth, and had higher initial relative abundance of Ureaplasma. In conclusion, longitudinal changes in the airway microbial communities of mechanically ventilated preterm infants may be associated with BPD severity, whereas cross-sectional analysis of airway ecology at 7 days of age did not reveal an association with BPD severity. Further evaluation is necessary to determine whether the observed longitudinal changes are causal or in response to clinical management or other factors that lead to BPD.

Ex vivo investigation of ocular tissue distribution following intravitreal administration of connexin43 mimetic peptide using the microdialysis technique and LC-MS/MS

This study aimed to develop and evaluate an ex vivo eye model for intravitreal drug sampling and tissue distribution of connexin43 mimetic peptide (Cx43MP) following intravitreal injection using the microdialysis technique and LC-MS/MS. An LC-MS/MS method was developed, validated, and applied for quantification of Cx43MP in ocular tissues. Microdialysis probes were calibrated for in vitro recovery studies. Bovine eyes were fixed in a customized eye holder and after intravitreal injection of Cx43MP, microdialysis probes were implanted in the vitreous body. Vitreous samples were collected at particular time intervals over 24 h. Moreover, 24 and 48 h after intravitreal injection ocular tissues were collected, processed, and analyzed for Cx43MP concentrations using LC-MS/MS. The LC-MS/MS method showed good linearity (r ² = 0.9991). The mean percent recovery for lower (LQC), medium (MQC), and higher quality control (HQC) (0.244, 3.906, and 125 μg/mL) was found to be 83.83, 84.92, and 94.52, respectively, with accuracy ranges between 96 and 99 % and limits of detection (LOD) and quantification (LOQ) of 0.122 and 0.412 μg/mL. The in vitro recovery of the probes was found to be over 80 %. As per microdialysis sample analysis, the Cx43MP concentration was found to increase slowly in the vitreous body up to 16 h and thereafter declined. After 48 h, the Cx43MP concentration was higher in vitreous, cornea, and retina compared to lens, iris, and aqueous humor. This ex vivo model may therefore be a useful tool to investigate intravitreal kinetics and ocular disposition of therapeutic molecules after intravitreal injection.

Scar Management in the Pediatric and Adolescent Populations

For most children and adolescents who have developed symptomatic scars, cosmetic concerns are only a portion of the motivation that drives them and their caregivers to obtain treatment. In addition to the potential for cosmetic disfigurement, scars may be associated with a number of physical comorbidities including hypertrichosis, dyshidrosis, tenderness/pain, pruritus, dysesthesias, and functional impairments such as contractures, all of which may be compounded by psychosocial factors. Although a plethora of options for treating scars exists, specific management guidelines for the pediatric and adolescent populations do not, and evidence must be extrapolated from adult studies. New modalities such as the scar team approach, autologous fat transfer, and ablative fractional laser resurfacing suggest a promising future for children who suffer symptomatically from their scars. In this state-of-the-art review, we summarize cutting-edge scar treatment strategies as they relate to the pediatric and adolescent populations.