The Effect of Botulinum Toxin A on the NADPH Oxidase System and Ischemia-Reperfusion Injury.

BACKGROUND: Despite the increasing popularity of various materials for ischemia-reperfusion (I/R) injury mitigation, research on botulinum toxin type A (BoNTA) remains limited. This study assesses BoNTA's efficacy in protecting flaps from I/R injury by inhibiting the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase system and reducing reactive oxygen species (ROS) production. METHODS: Seventy-six Sprague-Dawley rats were studied. We examined the effects of BoNTA on superoxide production in four rats using a lucigenin-enhanced chemiluminescence assay (LECL). Another group of 60 rats had their superficial inferior epigastric artery (SIEA) flaps treated with either BoNTA or saline and clamped for 0, 1, and 4 hours before reperfusion. Flap survival and histological outcomes were assessed five days post-operation. ROS production in SIEA flaps and femoral vessels was analyzed in 12 additional rats, post-I/R injury. RESULTS: The LECL results showed that the BoNTA group had significantly lower superoxide production compared to controls, with notable reductions at 4 hours. While no significant differences were noted at the 0 and 1-hour marks, the 4-hour mark showed significant protective effects in BoNTA-treated groups. The survival rate was 90% for BoNTA-treated rats versus 60% for controls ( P = 0.028). Significant reductions in ROS were also observed in the 4-hour I/R group. CONCLUSIONS: BoNTA effectively protects against I/R injury by inhibiting the NADPH oxidase system and reducing ROS levels. These results support further investigation into the specific mechanisms of NADPH oxidase inhibition by BoNTA and its potential clinical applications, given its safety profile. CLINICAL RELEVANCE STATEMENT: The findings from the present study are expected to provide a basis for clinical studies regarding this use of BoNTA.

The Effect of Botulinum Toxin A on NADPH oxidase system and Ischemia Reperfusion Injury.

BACKGROUND: While studies aimed at overcoming ischemia-reperfusion (IR) injury using various materials are becoming popular, studies using botulinum toxin type A (BoNTA) are still limited. This study tested the hypotheses that BoNTA can protect flaps from IR injury by inhibiting the NADPH oxidase system and suppressing ROS (reactive oxygen species) production. MATERIAL AND METHODS: The subjects were Sprague-Dawley rats (n = 76). In 4 rats, the effects of different dose of BoNTA on superoxide production was evaluated through lucigenin enhanced chemiluminescence assay (LECL) using SD rats' thoracic aorta ring. In 60 SD rats, The BoNTA and normal saline-pretreated superficial inferior epigastric artery (SIEA) flaps were clamped for 0, 1, and 4 hours, and reperfused. On the 5th day after the opeartion, well-maintained flaps were grossly inspected, survival rates were analyzed, and histological analysis was also performed. In 12 rats, after making IR injury through the same model, SIEA flap segments and femoral vessels were obtained, and ROS production was evaluated through LECL and dihydroethidium (DHE) staining. RESULTS: In LECL, the experimental group produced a smaller amount of superoxide than the control group through NADPH oxidase inhibition (p < .05). There was no significant difference between the experimental and control group in the 0, and 1 hour IR groups, but the experimental group (90%) showed a higher survival rate than the control group (60%) in the 4 hours IR group (p = .028). In the measurement of ROS production through LECL and DHE staining, there was no significant difference in the 0, and 1 hour IR groups, but a significant difference was shown in the 4 hours IR group in both the SIEA flaps and femoral vessels (p < .05). SUMMARY: This study verified hypothesis that BoNTA can protect flaps from IR injury by inhibiting the NADPH oxidase system and suppressing ROS production. Based on this research model, future research should be expanded into studies on subtypes or subunits of NADPH oxidase, and the findings from the present study are expected to contribute and lead to clinical studies on BoNTA, which has already been proven to be clinically safe.

Tailored versus conventional surgical debridement in complex facial lacerations in emergency department: A retrospective study.

Surgical debridement is an essential step in treating complex facial lacerations (CFL). As the CFL severity increases, conventional surgical debridement (CSD) of wound edges becomes difficult and may be insufficient. Because the severity and shape of each CFL vary, it is necessary to tailor the customized pre-excisional design, that is, tailored surgical debridement (TSD), for each case before performing surgical debridement. The use of TSD can enable effective debridement of CFL with higher severity. This study aimed to compare the cosmetic outcomes and complication incidence of CSD versus TSD according to CFL severity. In this retrospective observational study, eligible patients with CFL who visited the emergency department between August 2020 and December 2021 were examined. CFL severity was graded as Grades I and II. The outcomes of CSD and TSD were compared using the scar cosmesis assessment and rating (SCAR) scale, wherein a good cosmetic outcome was defined as a SCAR score of ≤ 2. The percentage of good cosmetic outcomes between the 2 groups was compared. The SCAR score and percentage of good cosmetic outcomes between the 2 groups were compared overall and by severity. For analyzing complication incidence, asymmetry, infection, and dehiscence incidence were compared. In total, 252 patients were enrolled [121 (48.0%) CSD and 131 (52.0%) TSD]. The median SCAR scores were 3 (1-5) and 1 (0-2) in all enrolled patients (P < .001), 2 (0-4), and 1 (0-1) in Grade I patients (P < .01), and 5 (4-6) and 1 (1-2) in Grade II patients (P < .001) in the CSD and TSD groups, respectively. The percentage of good cosmetic outcomes was 46.3% and 84.0% overall (P < .001), 59.6% and 85.0% in Grade I patients (P < .01), and 9.4% and 83.5% in Grade II patients (P < .001) in the CSD and TSD groups, respectively. The incidence of complications was significantly higher in the CSD group than in the TSD group, but this was limited to asymmetry. No significant difference was noted in infection or dehiscence. Compared with CSD, TSD can lead to an objectively good cosmetic prognosis at higher CFL severity and can reduce facial asymmetry occurrence.

Designing with relaxed skin tension line in perforator-based island flap for sacral sore reconstruction: A STROBE-compliant observational study.

Many various types of operative techniques have been performed used to treat make-up for sacral defects. Perforator-based flaps with flap transposition, but achieving an optimal flap design and tension-free flap closure without skeletonizing the perforator requires a great deal of clinical experience. In this study, we demonstrate perforator selection based on considerations of the relaxed skin tension line (RSTL), which has proven to be a suitable method of achieving an efficient flap design that enables primary closure. Twenty-five perforator-based flap procedures were performed on 25 patients at a single institution from February 2018 to January 2021. The medical records of patients were retrospectively reviewed. Twenty-three flaps survived completely. Two flaps developed partial tip necrosis but recovered after secondary healing, and 1 patient developed temporary congestion, which resolved spontaneously. No recipient or donor site recurrence or dehiscence was identified during follow-up. We report our clinical experiences of perforator-based flap use in the sacral region. When selecting an appropriate perforating vessel, 2 important points should be considered, that is, a flap long axis parallel to RSTLs and defect shape. According to the method presented in this paper, perforator-based flaps can be transposed safely and easily with few complications and serve as useful practice models to cover sacral defects.

Reconstruction of Sacral Pressure Ulcer Using a Modified Parasacral Perforator-Based Flap (Maple Leaf Design): An Easier Method for Beginners.

Background. Many different operative options have been used to cover sacral defects. Perforator flap enables wide defect reconstruction with long pedicle and a large arc of rotation while preserving gluteus maximus muscle, but the risk of vessel injury can jeopardize flap survival. Perforator-based flap, the flap transposed without skeletonization of the perforator, requires much experience to be perfect in flap design to achieve tension-free closure. Methods. Fourteen modified parasacral perforator-based flap procedures were carried out on 14 patients. The records of patients at Chungnam National University Hospital from February 2017 to January 2020 were retrospectively reviewed. Results. All 14 flaps survived completely. One patient developed localized hematoma, and another presented with latent seroma. No donor or recipient site dehiscence or recurrence occurred during follow-up. Conclusion. We present our experience of a parasacral perforator-based flap with modified design of bilobed flaps. It could be performed easily and safely with less wound dehiscence and serve as a good practice model for young surgeons to cover small to moderately sized defects.

Delayed Orbital Hemorrhage around Alloplastic Implants after Blowout Fracture Reduction.

Alloplastic implants have been used to repair orbital wall fractures in most cases. Orbital hemorrhage is a rare complication of these implants and has been reported rarely in Korea. The purpose of this article is to report a late complication case focusing on their etiology and management. A 20-year-old male patient underwent open reduction with Medpor (porous polyethylene) insertion for bilateral orbital floor fractures. The initial symptom occurred with proptosis in the right side as well as vertical dystopia, which had started 4 days earlier, 8 months after surgery. Any trauma history after the surgery was not present. We performed an exploration and removal of hematoma with Medpor titanium meshed alloplastic implant. A case of delayed orbital hematoma following alloplastic implant insertion was identified. It occurred within the pseudocapsule of the implant. One week after surgery, overall symptoms improved successfully, and no complications were reported during the 11-month follow-up period. Although rare, orbital hemorrhage is a potential complication of alloplastic orbital floor implants, which may present many years after surgery. As in the case presented, delayed hematoma should be included in the differential diagnosis of late proptosis or orbital dystopia.

The vascular system of the superior auricular artery: anatomical study and clinical application.

BACKGROUND: The retroauricular flap has many advantages for facial reconstruction, but it is difficult to perform reconstruction of the upper part of the auricle and its surroundings. METHODS: We investigated the relationship between the superior auricular artery and its surrounding structures through anatomic studies with seven fresh cadavers and applied the findings clinically. From February 2008 to December 2009, we performed 12 cases with the superior auricular artery island flap to reconstruct defects in the upper region of the auricle and its surroundings. RESULTS: We found that the superior auricular artery is a reliable pedicle for the retroauricular flap. All wounds of the patients were successfully closed, with the exception of one minor complication. The aesthetic outcomes of the donor and recipient sites were satisfactory. CONCLUSIONS: The superior auricular artery island flap has several advantages. Therefore, we suggest that the superior auricular artery island flap can be another choice for reconstructing soft tissue defects at the upper region of the auricle and its surrounding area.