Evaluations of patient-specific bolus fabricated by mold-and-cast method using computer numerical control machine tools†

The patient-specific bolus fabricated by a mold-and-cast method using a 3D printer (3DP) and silicon rubber has been adopted in clinical practices. Manufacturing a mold using 3DP, however, can cause time delays due to failures during the 3D printing process. Thereby, we investigated an alternative method of the mold fabrication using computer numerical control (CNC) machine tools. Treatment plans were conducted concerning a keloid scar formed on the ear and nose. The bolus structures were determined in a treatment planning system (TPS), and the molds were fabricated using the same structure file but with 3DP and CNC independently. Boluses were then manufactured using each mold with silicone rubbers. We compared the geometrical difference between the boluses and the planned structure using computed tomography (CT) images of the boluses. In addition, dosimetric differences between the two measurements using each bolus and the differences between the measured and calculated dose from TPS were evaluated using an anthropomorphic head phantom. Geometrically, the CT images of the boluses fabricated by the 3DP mold and the CNC mold showed differences compared to the planned structure within 2.6 mm of Hausdorff distance. The relative dose difference between the measurements using either bolus was within 2.3%. In conclusion, the bolus made by the CNC mold benefits from a stable fabricating process, retaining the performance of the bolus made by the 3DP mold.

Penile keloid formation post-circumcision: A case series and review of literature

The formation of penile keloid after circumcision is an uncommon complication. Herein, we report two pediatric cases of large circumferential keloids that developed post-circumcision and were successfully treated by surgical excision and intralesional triamcinolone injections. In addition, we provide a comprehensive review of the reported cases of penile keloids that developed after circumcision in the literature to highlight the various presentations, treatment options, and outcomes for this condition.

The Communication from Immune Cells to the Fibroblasts in Keloids: Implications for Immunotherapy

Keloids are a type of fibrotic disease characterized by excessive collagen production and extracellular matrix (ECM) deposition. The symptoms of pain and itching and frequent recurrence after treatment significantly impact the quality of life and mental health of patients. A deeper understanding of the pathogenesis of keloids is crucial for the development of an effective therapeutic approach. Fibroblasts play a central role in the pathogenesis of keloids by producing large amounts of collagen fibers. Recent evidence indicates that keloids exhibit high immune cell infiltration, and these cells secrete cytokines or growth factors to support keloid fibroblast proliferation. This article provides an update on the knowledge regarding the keloid microenvironment based on recent single-cell sequencing literature. Many inflammatory cells gathered in keloid lesions, such as macrophages, mast cells, and T lymphocytes, indicate that keloids may be an inflammatory skin disease. In this review, we focus on the communication from immune cells to the fibroblasts and the potential of immunotherapy for keloids. We hope that this review will trigger interest in investigating keloids as an inflammatory disease, which may open up new avenues for drug development by targeting immune mediators.

Spring-Powered Needle-Free Injection of Triamcinolone Acetonide and 5-Fluorouracil for Keloid Treatment

Introduction

Keloid is an abnormal fibroproliferative healing response characterized by excessive and invasive tissue growth beyond the wound boundaries. The conventional treatment involves injecting drugs such as triamcinolone acetonide (TA), 5-fluorouracil (5-FU), or their combination intralesionally. However, the pain associated with injections often leads to low patient compliance and treatment failure. The spring-powered needle-free injector (NFI) provides an affordable alternative option for drug delivery with reduced pain.

Case

This case report presents a 69-year-old female patient with a keloid treated using a spring-powered needle-free injector (NFI) for drug delivery. The keloid was assessed using the Vancouver Scar Scale (VSS) and the Patient and Observer Scar Assessment Scale (POSAS). The patient's pain level was measured using the Numeric Pain Rating Scale (NPRS). TA and 5-FU mixed with lidocaine were loaded into the NFI and injected at a dose of 0.1 mL/cm². The treatment was repeated twice a week. After four sessions, the keloid flattened by 0.5 cm, VSS score decreased from 11 to 10, and POSAS scores decreased from 49 to 43 (observer) and from 50 to 37 (patient). The NPRS during each procedure was 1, indicating minimal pain.

Discussion

The spring-powered NFI is a simple and cost-effective device that operates based on Hooke's law, producing a high-pressure fluid jet for effective skin penetration. The NFI demonstrated effectiveness in treating keloid lesions, resulting in visible improvement after four treatments.

Conclusion

The spring-powered NFI offers an affordable and painless alternative to keloid treatment.

Penile Keloid Successfully Cured in a Keloid High-Tendency Patient

Keloid scars are a relatively common condition but extremely rare in the penis. This case aims to be added to the previous 34 cases of penile keloid reported in the literature. We present the case of a 15-year-old patient with a high keloid-forming tendency who was successfully cured of penile keloid scarring with excision alone and without any adjuvant therapy. No recurrence was reported over eight years of follow-up. In contrast, at the same time, recurrence is frequently observed in other body parts after excision, making this particular part of the body an area of less keloid occurrence and recurrence.

Combination of fractional carbon dioxide laser and topical triamcinolone vs intralesional triamcinolone for keloid treatment: A randomised clinical trial

To compare the therapeutic effect of fractional carbon dioxide (CO₂) laser + topical triamcinolone (TA) with intralesional TA on keloids. Twenty‐two participants were randomised into two groups: group A, treated with fractional CO₂ laser + topical TA, and group B, treated with intralesional TA. The interventions were performed at every 4‐week interval until the keloids were resolved or at the completion of 1 year. At each session, the scar volume, Vancouver Scar Scale (VSS) were assessed. Recurrence was observed for 1 year. The mean scar volumes and VSS scores were not significantly different between the two groups. After 1 year, the scar volume change in group B was greater than group A (86.5% vs 59.1%, P‐value = .016). The mean VSS scores were significantly decreased in group A (8.0 ± 1.5 to 4.8 ± 1.6, P‐value <.001) and group B (8.4 ± 0.8 to 4.8 ± 1.6, P‐value <.001). The keloids were completely resolved in 63.6% and 72.7% of the patients, and recurrence was observed in 9.1% and 18.2% of the patients in groups A and B, respectively. The combination of fractional CO₂ laser with topical TA was an alternative option for the treatment of keloids.

Keloid Scars: An Updated Review of Combination Therapies

Keloid scars are a common yet poorly understood complication of wound healing that can cause a diminished quality of life. Currently, there is little agreement amongst the medical community regarding the best treatment modality for keloids. For this reason, we have created an updated review of the most successful combination therapies for keloid scars and compared their efficacy based on rates of recurrence following treatment. Additionally, these combination therapies have been compared with intralesional triamcinolone acetonide corticosteroid (TAC), which is considered the mainstay monotherapy for keloids. All combination therapies included in our review were shown to produce superior outcomes than TAC monotherapy. We have also found that certain combination therapies are known to produce superior results when used in specific anatomic locations. Intralesional TAC plus intralesional cryotherapy appeared to have the most promising results for non-auricular keloids, and the authors suggest considering this as a first-line treatment. Additionally, the use of surgical excision plus compression therapy achieved superior results for auricular keloids and should be considered first-line for keloids in these locations.

Treatment of Pain in Keloids Using Only a Long-Pulsed 1064 nm Nd:YAG Laser

BACKGROUND AND OBJECTIVE

Keloids are benign lesions arising from overproduction of the extracellular matrix and abnormal collagen deposition by dermal fibroblasts. This altered wound healing typically occurs in response to dermal trauma. Keloid treatment poses a challenge due to the variable nature of treatment response, which can be affected by the size, appearance, and associated symptoms of erythema, pruritus, and pain. Recently, successful treatment of keloids has been reported using the Nd:YAG laser in conjunction with 5-fluorouracil and intralesional corticosteroids. We present a series of patients with symptomatic keloids, who we treated with only a 1064 nm Nd:YAG laser.

STUDY DESIGN/MATERIALS AND METHODS

Eight patients of Fitzpatrick skin types I-VI presented for treatment of keloids with associated symptoms of pain. The keloids were most commonly located on the trunk, and seven patients had intralesional steroid injections prior to presentation with persistence of symptoms. Patient treatment consisted of two passes under a long-pulsed 1064 nm Nd:YAG laser with a 10 mm spot size, a fluence of 18-19 J/cm² , and 60 ms pulse duration every 3-8 weeks. Patient-reported pain scores were collected before and after treatment.

RESULTS

Following treatment, transient erythema and mild edema were noted at the treatment site. All patients reported improvement in the symptoms of pain, with an average of a 5-point reduction using a 10-point scale (R: 2-10). Five out of eight patients had total resolution of their pain. An average of 3.25 treatments (R:1-5) were needed for patients to first notice an improvement in the pain. A Wilcoxon signed-rank test showed that treatment with a 1064 nm laser elicited a statistically significant improvement in pain in individuals with keloids (Z = 2.46, P = 0.01). No patients in our study suffered any scarring or pigment changes as a result of these treatments.

CONCLUSION

Keloids are a common condition with variable rates of treatment satisfaction. Lasers have been used in an attempt to improve clinical appearance and associated symptoms. We report a significant reduction in pain for patients treated exclusively with a 1064 nm Nd:YAG laser. Lasers Surg. Med. © 2020 Wiley Periodicals LLC.