Absorption and reduced scattering coefficient estimation in pigmented human skin tissue by experimental colorimetric fitting.

This study aims to estimate the optical properties, absorption (µ a), and reduced scattering (µ s ') coefficients of ex vivo human skin through the individual typology angle (ITA) by only using the skin color parameters. Human skin samples were grouped according to their ITA value and measured using a colorimeter for validation. An integrating sphere and the inverse adding-doubling algorithm were applied to compute the samples µ a and µ s '. The µ a increases as the ITA decreases. An axis swap was performed to generate the µ a versus the ITA for all wavelengths between 500 nm and 800 nm with a spectral resolution of 10 nm. Linearization was performed and a correlation was found. An equation to fit µ a based solely on the ITA values was estimated. The µ s ' does not change with ITA, but it could be fit with an inverse power law as a function of the wavelength. Both equations have a coefficient of determination (R 2) higher than 0.93, indicating a good agreement with our model. An experimental model to estimate the absorption and reduced scattering coefficients of ex vivo human skin through ITA was found. The model has high agreement with the experimental data, with an R 2 between 0.932 and 0.997, and these findings may be relevant for photobiomodulation and light treatment applications to estimate the effect of the melanin on the therapy.

Comparative cohort analysis of pressure ulcer/injury in intensive care unit patients before and during the COVID-19 pandemic.

COVID-19 has emerged as a global pandemic leading to an increase in hospitalization and intensive care unit (ICU) admissions worldwide. Due to severe acute respiratory distress syndrome (ARDS), many patients require prone positioning, which is associated with increased pressure ulcer/injury (PU/PI) incidence. COVID-19 pathophysiology may favor the occurrence of PU/PI due to hypoxemia, inflammatory status, and vasculopathy. This study aimed to compare the incidence of PU/PI in ICU patients before and during the COVID-19 pandemic. A retrospective cohort study was conducted at a university hospital in Brazil. Data from the medical charts of every adult patient admitted to ICU from March to July 2019 and the same period in 2020 were collected. The group from 2019 included 408 patients admitted due to multiple causes, and the group from 2020 included 229 patients admitted due to COVID-19 infection. The incidence of PU/PI was significantly higher in patients admitted in 2020 compared to 2019 (62,5 vs. 33,8%, respectively). Also, PU/PI location and severity have been different between groups, with the patients with COVID-19 (2020 group) more exposed to stage 3, 4, and non-stageable lesions, as well as more PU/PI on face skin and other less common locations. In conclusion, the COVID-19 pandemic has highlighted a higher PU/PI incidence. ICU patients were older during the pandemic, had higher body mass index and comorbidities, and needed more invasive medical devices and pronation. The occurrence of PU/PI was also associated with prolonged hospitalization and mortality.

Evaluation of Clinical and Biomechanical Features of Scars Resulting from the Treatment of Burn Contractures Comparing Acellular Dermal Matrices: A Randomized Clinical Trial.

OBJECTIVE: The aim of this study was to compare clinical and biomechanical features of scars resulting from the treatment of burn contractures using different acellular dermal matrices (ADM). SUMMARY BACKGROUND DATA: Extensive burns often lead to severe sequelae, such as skin contractures, that can be treated using ADM to improve the quality of these scars. METHODS: A prospective, randomized and controlled clinical trial was performed including patients with burn contractures at least 1-year post-burn, treated using split-thickness skin graft (STSG). These patients were randomized into 4 groups: control (received only STSG without ADM), Integra (ADM + STSG), Matriderm (ADM + STSG), and Pelnac (ADM + STSG). Exclusion criteria were loss of follow-up and graft integration failure. The evaluation was performed using the Vancouver Scar Scale (VSS), the durom-eter, and the cutometer in areas of normal skin, hypertrophic scar, and surgical scar, at least 1 year after the surgery. RESULTS: In the VSS, durometer, and cutometer evaluation, there was no difference in the comparison of surgical scars among groups. Analyzing each group, with an intraindividual evaluation comparing areas of normal skin with surgical scars, the results suggested a possibility of a surgical scar hardness closer to normal skin for Integra and Matriderm groups measured with the durometer. In the cutometer evaluation, surgical scars were not comparable to areas of normal skin. CONCLUSIONS: This study suggests that there is no difference in the quality of scar assessed through the analysis of clinical and biomechanical features comparing acellular dermal matrices (Integra, Matriderm, and Pelnac) and only split-thickness skin graft without a dermal matrix.

The role of the unilateral pectoralis major muscle flap in the treatment of deep sternal wound infection and dehiscence.

Deep sternal wound infection and dehiscence has been classified as complex wound, and its treatment is a challenge for the surgeon. There are many flap choices for its treatment, each one having advantages and drawbacks. The article by Wang et al. evidenced that the unilateral pectoralis major muscle flap is a simple and effective option for wound closure resulting from sternotomy dehiscence in infants and children. The report discussed herein highlights that the unilateral pectoralis major muscle flap has been a good and feasible option for the reconstruction of the sternal wound in adults, as previously described by our group and other authors. This technique presents low morbidity and acceptable esthetic and functional results, providing stability to the sternal region.

Evaluation of contraction of the split-thickness skin graft using three dermal matrices in the treatment of burn contractures: A randomised clinical trial.

Burn injuries commonly result in serious sequelae (such as skin contractures) in surviving patients, for which no single optimal solution is known. The goal of this study was to compare the late contraction of autologous skin grafts with or without dermal matrices used in the treatment of patients with burn contractures. This parallel design prospective, randomised and controlled clinical trial included patients with burn contracture treated using autologous skin grafts and dermal matrix. Patients were randomly assigned to one of the four groups: Integra® matrix (n = 10), Pelnac® matrix (n = 10), Matriderm® matrix (n = 9) or a Control Group (n = 10, without dermal matrix, only skin graft). The boundaries of skin defect were marked and transferred to a flat sterile surface for area measurement. The current area of the skin grafts was measured during surgery and compared with those obtained at 1, 3, 6 and 12 months postoperatively. Twelve months after surgery, the Control Group presented lower rates of skin graft contraction than Integra® (p < 0.01), Matriderm® (p = 0.01) and Pelnac® (p < 0.01) groups. Pelnac® resulted in larger skin graft contraction than Matriderm® (p < 0.01) and Integra® (p = 0.02), while differences between Integra® and Matriderm® were not significant (p = 0.16). The comparison between intraoperative and 12 months after surgery showed that the worst mean rates of skin graft contraction were from the Pelnac® (51.79%) and Matriderm® (59.17%). In patients with burn contractures, the use of these three dermal matrices did not reduce or avoid the occurrence of late contraction of the skin graft, so their use for this purpose should be carefully evaluated.

Lucio's phenomenon: A systematic literature review of definition, clinical features, histopathogenesis and management.

Leprosy is a chronic disease with clinical presentations according to the immunologic spectrum. Lepromatous form is the most advanced, with the highest transmissibility and risk of causing disabilities. Lucio's phenomenon is a rare manifestation among lepromatous patients with a rapid and severe evolution and high mortality. It is difficult to differentiate from ulcerative/necrotic erythema nodosum leprosum and has no consensus on how it should be treated. This article is a qualitative review of the literature after the introduction of multidrug therapy, aiming to bring consensus related to the clinical, laboratory and histopathological diagnostic criteria of the disease and its management.

The role of negative pressure wound therapy (NPWT) on the treatment of pyoderma gangrenosum: A systematic review and personal experience.

Pyoderma gangrenosum (PG) is a rare painful ulcerative neutrophilic inflammatory skin disease, necessitating a high level of diagnostic suspicion associated with appropriate treatment to avoid progression. Negative pressure wound therapy (NPWT) has been efficiently used in the treatment of different types of wounds. However, the role of NPWT in the management of PG is still controversial, due to the risk of the pathergy phenomenon. In this article, we conducted a systematic review (according to the PRISMA guidelines) on the use of NPWT in the treatment of PG, and we report our personal experience with two patients treated with this device. The result of the review showed that articles on the topic are, in their entirety, of low levels of evidence, such as case series, case reports, and reviews. Improvement in wound healing with the use of NPWT was observed in 85.1% of the patients studied. Besides, a significant association between improvement in wound healing with NPWT and immunosuppressive therapy was observed. Regarding the cases reported here, both showed good outcomes with the use of NPWT and skin graft during the treatment of PG injuries. Due to the rarity of PG, there is a scarcity of studies with robust evidence for standardization and comparison between treatments, which consequently makes it difficult to select therapeutic options. However, based on this systematic review and reported cases, we consider NPWT a safe option for adjuvant treatment of wounds caused by PG if combined with systemic immunosuppression, which plays a key role in greater chances of successful treatment. This approach should be recommended, whenever possible, associated with skin grafting to accelerate wound closure. The role of negative pressure wound therapy (NPWT) on the treatment of pyoderma gangrenosum: a systematic review and personal experience.

Acute otitis externa because of negative pressure wound therapy applied over the head and ear canal for scalping treatment.

Scalping is considered a complex wound with difficult treatment, requiring early surgical intervention, reconstructive plastic surgery, and a multidisciplinary team. The reconstruction of the scalp frequently requires a combination of therapies, including temporary coverage, such as negative pressure wound therapy (NPWT). Complications of NPWT, such as bleeding, infection, and pain, have been described. However, there is no report of acute otitis externa (AOE) because of NPWT. In this article, we present an unprecedented clinical case - a female patient who developed AOE after scalping treatment with NPWT applied over the head and ear canal. We consider that it may be a result of the direct physical action of subatmospheric pressure, the presence of dressing covering the external meatus, and alteration of the bacterial population.

Early Application of Microsurgical Flaps in the Electric Burns of Extremities: A Two Institutional Case Series.

Some groups have avoided early microsurgical flaps in electrical burns under the pretext of injury to the microvasculature, which could increase vascular thrombosis. However, this option frequently results in amputation of the extremity. This study aims to evaluate the early application of microsurgical flaps for the treatment of electrical burns of extremities. A case series was retrospectively evaluated including patients with electrical trauma in extremities undergoing early microsurgical reconstruction. Data were obtained from medical charts, including age, trauma location, flap type and microvascular anastomosis, the need for other procedures, postoperative complications, the length of hospital stay after the flap surgery, and patient outcomes. Five microsurgical flaps were performed in less than 30 days to trauma, one anterolateral thigh flap to cover skin failure in upper limb, and four radial forearm flaps to cover failure in feet. The patient ages had a mean of 25.8 years (from 12 to 42 years). The microsurgical procedure occurred from 21 to 27 days after the burn, with a mean of 24.2 days. Hospital discharge had a mean of 26.6 days (from 19 to 35 days after the surgery). Only one patient required reintervention for re-anastomosis. All patients had a good flap viability, avoiding amputation of the affected extremity and with a proper preservation of function. The early application of microsurgical flaps for patients with electrical burns of extremities may provide adequate, sturdy, and stable skin coverage, contributing to the treatment of noble structures exposed and avoiding amputation of the extremities.

Unilateral pectoralis major muscle flap for the treatment of sternal wounds due to Ludwig's angina.

Necrotising descending mediastinitis may rarely originate from Ludwig's angina, which is an infection of the submandibular space. The use of the bilateral pectoralis major muscle flap for the treatment of sternal wound dehiscence is common, but reports of the unilateral application of this flap are scarce. This study aims to report the use of the unilateral pectoralis major muscle flap for the treatment of sternotomy dehiscence in a patient with mediastinitis due to Ludwig's angina. A 21-year-old male patient underwent an exploratory cervicotomy and median sternotomy for drainage of a submandibular infection that extended to the anterior, retropharyngeal and mediastinal cervical spaces. The patient had dehiscence of the sternal wound, and the unilateral pectoralis major muscle flap was used for reconstruction of the defect. This flap was able to completely cover the area of dehiscence of the sternotomy, and the patient presented a good postoperative evolution, without complications. The reconstruction technique using the unilateral pectoralis major muscle flap was considered a good option for the treatment of sternotomy dehiscence. It is an adjuvant method in the treatment of infections such as mediastinitis and osteomyelitis of the sternum secondary to Ludwig's angina, allowing a stable coverage of the sternum.

Outcomes of Immediate Internal Pudendal Artery Perforator Flap Reconstruction for Irradiated Abdominoperineal Resection Defects.

BACKGROUND: There are many previous reports for using the internal pudendal artery perforator flap in vulvovaginal reconstruction; however, reports of this flap for perineal reconstruction after abdominoperineal excision of the rectum are scarce. OBJECTIVE: The purpose of this study was to evaluate the outcomes of immediate internal pudendal artery perforator flap reconstruction for irradiated abdominoperineal resection defects. DESIGN: This was a prospective case series. SETTINGS: This flap could represent a step forward over other perineal flap approaches or primary closure. PATIENTS: A total of 73 consecutive patients with anorectal tumors were included. INTERVENTIONS: The study included immediate perineal reconstruction using 122 internal pudendal artery perforator flaps after abdominoperineal excision of the rectum. MAIN OUTCOME MEASURES: Dimensions of the perineal defect (in centimeters squared), hospital stay (days), healing time (days), and postoperative complications (Clavien-Dindo grades) were measured. RESULTS: The means of the perineal defect, hospital stay, and healing time were 51.62 cm, 15.94 days, and 38.52 days. The higher the patient BMI, the longer healing time (p = 0.02); Clavien-Dindo complications grades III to IV were greater in patients with perineal defect ≥60 cm (p = 0.03; OR = 10.56); postoperative complications were higher both in patients with anal squamous cell carcinoma (p = 0.005; OR = 6.09) and in patients with comorbidities (p = 0.04; OR = 2.78); hospital stay (p= 0.001) and healing time (p < 0.001) were higher in patients who had postoperative complications. The complete perineal wound healing at 12 weeks was achieved by 95% of patients, and our 30-day mortality rate was 4%. LIMITATIONS: As a nonrandomized study, our results have to be interpreted with caution. CONCLUSIONS: Multiple previously described advantages associated with internal pudendal artery perforator flap were also observed here, reinforcing the idea that it is reliable, versatile, and a useful option for perineal reconstruction after abdominoperineal excision of the rectum. Therefore, we propose that this flap could be considered as the first choice for perineal reconstruction in selected patients with moderate and some large defects after abdominoperineal excision of the rectum. See Video Abstract at http://links.lww.com/DCR/A367.

Chimerical anterolateral thigh flap for plantar reconstruction.

OBJECTIVE: The purpose of this study is to evaluate the results of reconstruction and rehabilitation of patients with plantar defects by using a chimerical flap of muscle and skin from anterolateral thigh. METHODS: Twenty-five patients with plantar defects were reconstructed with a chimerical anterolateral thigh (ALT) flap, composed by a vastus lateralis muscle segment and a thinned skin island. Neurorrhaphy between lateral femoral cutaneous nerve and calcaneal nerve was performed in 7 patients. Evaluation of flap contour and stability and patient ambulation was performed 6 and 12 months after surgery. Evaluation of cutaneous sensiblity of ALT flap and contralateral thigh was performed 12 months after surgery using Pressure Specified Sensory Device™ (PSSD™). RESULTS: Flap viability was complete in 23 patients and 2 patients had complications with partial flap loss of its cutaneous component. Six months postoperatively, flap contour, and stability was considered good in 19 and 21 patients respectively, and all 25 patients presented good ambulation. Twelve months postoperatively, all 25 patients presented good flap contour and stability, as well as good ambulation. All 7 flaps undergoing to reinnervation partially recovered cutaneous sensibility in comparison to donor site (contralateral thigh). Cutaneous tactile thresholds (g/mm(2) ) of static one-point test and moving one-point test from the ALT flap and the contralateral thigh presented statistically significant differences, for both comparisons (P = 0.009, P = 0.002). CONCLUSION: This flap is suitable for reconstruction of plantar defects, with good flap contour and stability, proper patient ambulation and low complication rates.

Evaluation of cutaneous sensibility of the internal pudendal artery perforator (IPAP) flap after perineal reconstructions.

BACKGROUND: In oncological perineal reconstructions, the internal pudendal artery perforator (IPAP) flap is our flap of choice, supplied by perforator vessels from the internal pudendal artery and innervated by branches from the pudendal nerve and the posterior femoral cutaneous nerve. Data related to the evaluation of its cutaneous sensibility are scarce, discrepant, and subject to methodological criticism. OBJECTIVE: The objective of this study was to evaluate the cutaneous sensibility of the IPAP flap 12 months after perineal reconstruction and compare it with the preoperative cutaneous sensibility of the gluteal fold (flap donor area). METHODS: A prospective study of 25 patients undergoing abdominoperineal excision of rectum (APER) and reconstruction with bilateral VY advancement IPAP flap was conducted. The tactile, pain, thermal, and vibration sensibilities were analyzed in four areas of the gluteal fold preoperatively and in the four corresponding areas of the flap 12 months after surgery. Tactile sensibility was assessed using the Pressure Specified Sensory Device™ (PSSD™), which measures the pressure applied to the skin. The other types of sensibility were analyzed using a needle for pain, hot/cold contact for thermal, and a tuning fork for vibration sensibility. RESULTS: A comparison between tactile sensibility thresholds on the gluteal fold preoperatively and on the flap 12 months after surgery showed no statistically significant difference, with p values>0.05 in all four areas evaluated. All patients had preserved pain, thermal, and vibration sensibility in all four areas, postoperatively. CONCLUSION: In oncological perineal reconstructions after APER, it is expected that the cutaneous sensibility on the IPAP flap be maintained.

Anatomical comparison among the anterolateral thigh, the parascapular, and the lateral arm flaps.

OBJECTIVE: This study aims to compare the major anatomical aspects among anterolateral thigh, parascapular and lateral arm flaps. METHODS: Sixty flaps were dissected in 20 human cadavers, comparing their vascular pedicle length, flap thickness and arterial/venous pedicle diameters. RESULTS: The vascular pedicle length (from the origin of the vascular pedicle to its entry into the skin flap) of anterolateral thigh flap (13.43 ± 3.92 cm, lateral circumflex femoral artery) was longer than parascapular (9.07 ± 1.20 cm, circumflex scapular artery) and lateral arm flap (8.90 ± 1.65 cm, posterior collateral radial artery) (P < 0.001). The thickness of lateral arm flap (6.32 ± 2.33 mm) was lesser than parascapular (8.59 ± 2.93 mm) and anterolateral thigh flap (9.30 ± 3.54 mm) (P < 0.001). The arterial/venous pedicle diameters of lateral arm flap (2.37 ± 0.69 mm / 2.61 ± 0.74 mm) were lesser than parascapular (3.46 ± 0.80 mm / 4.07 ± 0.87 mm) and anterolateral thigh flap (3.26 ± 0.74 mm / 3.87 ± 0.70 mm) (P < 0.001). CONCLUSIONS: The vascular pedicle length of anterolateral thigh flap was the longest and that lateral arm flap presented a pedicle with the smallest arterial and venous diameters, in addition to being the thinnest flap.

The thoracodorsal artery perforator flap in the treatment of axillary hidradenitis suppurativa: effect on preservation of arm abduction.

UNLABELLED: Hidradenitis suppurativa is a chronic, recurrent inflammatory disease of the skin characterized by abscesses and scars. The axillary region is predominantly affected, leading to limited mobility of the arm due to scar retraction. This prospective study aimed to analyze the surgical treatment of severe lesions of axillary hidradenitis suppurativa by using the thoracodorsal artery perforator flap while focusing on the preservation of arm abduction. We enrolled 12 patients with severe axillary hidradenitis suppurativa who underwent bilateral surgical treatment of their lesions by radical excision, followed by immediate reconstruction with the thoracodorsal artery perforator flap. The amplitude of arm abduction was measured preoperatively and 6 months postoperatively by goniometry, and statistical analysis was performed using Student's t test. Preoperative and 6-month postoperative mean amplitude of arm abduction were 98.7 degrees and 152.7 degrees, respectively, with a significant mean increase of 54 degrees (p<0.0001). The thoracodorsal artery perforator flap can be used as a good option for axillary reconstruction after radical excision of severe lesions of hidradenitis suppurativa, and its use would allow a significant increase in the amplitude of arm abduction. It has several other advantages when compared with other types of coverage, including its anatomical proximity to the axilla, similar thickness, and high-quality skin. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, V.