Case report: Long-term follow-up of a large full-thickness skin defect treated with a photosynthetic scaffold for dermal regeneration.

It is broadly described that almost every step of the regeneration process requires proper levels of oxygen supply; however, due to the vascular disruption in wounds, oxygen availability is reduced, being detrimental to the regeneration process. Therefore, the development of novel biomaterials combined with improved clinical procedures to promote wound oxygenation is an active field of research in regenerative medicine. This case report derives from a cohort of patients enrolled in a previously published ongoing phase I clinical trial (NCT03960164), to assess safety of photosynthetic scaffolds for the treatment of full skin defects. Here, we present a 56 year old patient, with a scar contracture in the cubital fossa, which impaired the elbow extension significantly affecting her quality of life. As part of the treatment, the scar contracture was removed, and the full-thickness wound generated was surgically covered with a photosynthetic scaffold for dermal regeneration, which was illuminated to promote local oxygen production. Then, in a second procedure, an autograft was implanted on top of the scaffold and the patient's progress was followed for up to 17 months. Successful outcome of the whole procedure was measured as improvement in functionality, clinical appearance, and self-perception of the treated area. This case report underscores the long-term safety and applicability of photosynthetic scaffolds for dermal regeneration and their stable compatibility with other surgical procedures such as autograft application. Moreover, this report also shows the ability to further improve the clinical outcome of this procedure by means of dermal vacuum massage therapy and, more importantly, shows an overall long-term improvement in patient´s quality of life, supporting the translation of photosynthetic therapies into human patients.

A First in Human Trial Implanting Microalgae Shows Safety of Photosynthetic Therapy for the Effective Treatment of Full Thickness Skin Wounds.

Insufficient oxygen supply represents a relevant issue in several fields of human physiology and medicine. It has been suggested that the implantation of photosynthetic cells can provide oxygen to tissues in the absence of a vascular supply. This approach has been demonstrated to be successful in several in vitro and in vivo models; however, no data is available about their safety in human patients. Here, an early phase-1 clinical trial (ClinicalTrials.gov identifier: NCT03960164, https://clinicaltrials.gov/ct2/show/NCT03960164) is presented to evaluate the safety and feasibility of implanting photosynthetic scaffolds for dermal regeneration in eight patients with full-thickness skin wounds. Overall, this trial shows that the presence of the photosynthetic microalgae Chlamydomonas reinhardtii in the implanted scaffolds did not trigger any deleterious local or systemic immune responses in a 90 days follow-up, allowing full tissue regeneration in humans. The results presented here represent the first attempt to treat patients with photosynthetic cells, supporting the translation of photosynthetic therapies into clinics. Clinical Trial Registration: www.clinicaltrials.gov/ct2/show/NCT03960164, identifier: NCT03960164.

Colgajo sural superficial a pedículo distal excluyendo nervio sural: casuística / Superficial distally based sural flap with exclusion of the sural nerve: clinical cases

Introducción y objetivo: El colgajo fasciocutáneo sural superficial a pedículo distal ha sido utilizado desde hace tiempo para la reconstrucción del tercio distal de la pierna, tobillo y talón, y su irrigación también ha sido establecida.Presentamos nuestra casuística demostrando que este colgajo puede sobrevivir excluyendo de su composición el nervio sural y por lo tanto conservar la sensibilidad de tercio distal póstero-lateral de pierna y borde lateral del pié, conservando también su irrigación indemne.Material y método.Recogemos 40 pacientes con fractura expuesta de tercio distal de pierna, tobillo y talón, sometidos a reconstrucción con colgajo sural superficial a pedículo distal excluyendo el nervio sural, desde 1998 hasta 2019.Las edades fuctuaron entre 20 y 55 años; 35 hombres y 5 mujeres.En todos los pacientes realizamos prueba de presión cutánea suave con plumilla (pinch test ) y prueba del pinchazo cutáneo (pin prick), y en 4 neurografía sensorial.Resultados.La irrigación del colgajo no se vio alterada al excluir el nervio sural. Hubo 2 necrosis distales del colgajo solucionadas con injerto dermo-epidérmico y/o avance del colgajo. En 3 pacientes hubo edema resuelto con elevación de pierna y vendaje suave. En 4 pacientes hubo celulitis que cedió con antibióticos. La sensibilidad cutánea en el tercio distal de la pierna en su porción posterior y lateral, y en el borde lateral del pie se conservó sin alteraciones.Conclusiones.En nuestra casuística, la exclusión del nervio sural no alteró la irrigación del colgajo En nuestros pacientes, la sensibilidad cutánea del tercio distal de la cara póstero-lateral de la pierna y el borde lateral del pié no se alteró, siendo corroborada por la clínica y por la neurografía sensorial. (AU)

Background and objective: Background and objective. The distally based superficial sural artery flap has been used for lower limb reconstruction for long time. The blood supply for this flap has been studied for many authors.We present our casuistry showing that this flap can survive excluding the sural nerve from its composition and therefore preserve the sensitivity of the distal postero-lateral third of the leg and the lateral border of the foot, also preserving its undamaged irrigation.Methods.We have operated on 40 patients since 1998 to 2019, 35 men and 5 female, age ranged from 20 to 55 years old, using a superficial distally based sural flap, excluding the sural nerve. The pinch and the pin prick test were done in all patients.Results.In spite of excluding the sural nerve, the arterial blood supply to the flap was not compromised. There were 2 distal partial necrosis healed with flap advance and or split thickness skin graft. Edema was presented in 3 patients disappearing with limb elevation and light dressing. Cellulitis was presented in 4 patients and disappeared with antibiotics. Cutaneous sensitivity in the posterior and lateral distal third portion of the leg and in the edge of the foot was unalterable.Conclusions.In our clinical cases, the arterial blood supply to the distally based sural flap is not compromised with the exclusion of the sural nerve. The clinic and neurography show the patency of the sensation in the skin of the lateral and posterior part of the distal third of the leg and the lateral aspects of the foot.These findings allow to exclude the sural nerve from the flap insuring the blood supply and avoiding the possible pressure sores when the workers use their security shoes. (AU)

Manejo de queloides mediante combinación de cirugía y radioterapia con haz de electrones / Management of keloid through combination of surgery and radiotherapy with electron beam

INTRODUCCIÓN Y OBJETIVO: La formación de queloides condiciona un deterioro en la calidad de vida de los pacientes por causar desfiguración cosmética, dolor y prurito. A pesar de que existe una amplia gama de opciones terapéuticas e incluso combinación de estas, aún existen tasas de recurrencia elevadas que hacen del tratamiento de los queloides un desafío complejo. Recogemos nuestra tasa de recurrencia de queloides en diferentes áreas corporales tras cirugía asociada a radioterapia con haz de electrones en el postoperatorio inmediato mediante un protocolo de radioterapia definido. MATERIAL Y MÉTODO: Estudio de tipo ambispectivo en los centros de Cirugía Plástica del Hospital del Salvador y Clínica Santa María en Santiago (Chile) entre 2010 y 2017 sobre pacientes intervenidos por queloides mediante cirugía y tratamiento protocolizado con radioterapia de electrones. Excluimos pacientes que no asistieron al tratamiento con radioterapia, o se realizó después de 24 horas, o no se les realizó seguimiento durante al menos 3 meses. Evaluamos datos demográficos, clínicos, antecedentes de procedimientos anteriores frustrados, número de queloides y recurrencia. Utilizamos como prueba estadística chi-cuadrado con significancia estadística p ≤ 0.05. RESULTADOS: Estudiamos un total de 15 pacientes con un total de 32 queloides intervenidos en distintas áreas corporales con seguimiento promedio de 862 días. En todos realizamos el procedimiento sin inconvenientes y con buena tolerancia. El promedio de recidiva total fue del 34%, siendo la zona de mayor recurrencia la dorsal (83%) y la de menor la auricular donde no hubo recidivas. CONCLUSIONES: En nuestra experiencia, el tratamiento quirúrgico escisional de los queloides, seguido de radioterapia con haz de electrones según el protocolo expuesto, resultó sin recidivas en la zona auricular

BACKGROUND AND OBJECTIVE: Keloids cause deterioration in the quality of life of patients due to cosmetic disfigurement, pain and pruritus. Although there is a wide range of therapeutic options and even a combination of these, there are still high recurrence rates that make keloids treatment a challenge. We report our rate of recurrence of keloid in different body areas after surgery associated with radiotherapy electron beam in the immediate postoperative period using a defined radiotherapy protocol. METHODS: An ambispective study was carried out in the Plastic Surgery Unit at Salvador Hospital and Santa María Clinic in Santiago (Chile) between 2010 and 2017, colleting patients operated on by keloids with surgery and protocolized treatment of electron radiation therapy. Patients who did not attend the radiotherapy treatment, it was performed after 24 hours, or they were not followed up for at least 3 months, were excluded. We evaluated demographic, clinical data, past history of frustrated procedures, keloid number and keloid recurrence. Chi-square statistical test was used using statistical significance p ≤ 0.05. RESULTS: A total of 15 patients with 321 keloids in different body areas were treated, with an average follow-up time of 862 days. All patients underwent surgical and radiotherapy treatment without inconveniences and good tolerance. The average total recurrence was 34%, with the greatest recurrence in the dorsal area (83%) and with no recurrences in the auricular one. CONCLUSIONS: Excisional surgical treatment of keloids, followed by beam radiation therapy according to the protocol described, results in no recurrence in the auricular área

Squamous Cell Carcinoma as a Result of Likely Industrial Grade Ruptured Poly Implant Prosthèse Silicone Buttock Implants.

The Poly Implant Prosthèse (PIP) implants were withdrawn from the market in 2010 due to the use of a nonmedical grade silicone filler. In 2012, the French medical authorities and the International Confederation of Societies of Plastic, Reconstructive and Aesthetic Surgery recommended the extraction of PIP implants. However, during the duration of this scandal, each country in the world did not agree with a uniform procedure, and this rule was not implemented in its entirety. Although laboratory test results on PIP implants were negative for cytotoxicity and genotoxicity, there are many reports in the literature of several complications associated with PIP implants, including high rupture rates and the fact that they are 3 to 5 times more likely to produce local tissue reactions. On the other hand, the development of more strange and worse prognosis complications, such as the development of squamous carcinoma associated with the use of silicone implants (not necessarily related to PIP implants), is less known. To date, only 6 cases have been reported, and all are related to breast augmentation. The authors made the first report of primary gluteal squamous cell cancer related to rupture and delayed removal of PIP silicone buttock implants.

Método de aislamiento, cultivo y precondicionamiento con hipoxia de células madre derivadas de tejido adiposo en ratas / Method of isolation, culture and hypoxia preconditioning of adipose tissue stem cells in rats

Introducción y objetivo. Las células madre son candidatas terapéuticas para una amplia gama de enfermedades. Resultan de gran interés en Cirugía Plástica para el tratamiento de heridas crónicas, transferencia de tejido adiposo y colgajos. El objetivo de este estudio es describir el método de aislamiento, cultivo y caracterización de células madre derivadas de tejido adiposo y cómo estas pueden precondicionarse con hipoxia y generar cambios in vitro en su capacidad proliferativa y migratoria. El trabajo es un complemento didáctico a otro publicado por nosotros en esta misma revista utilizando esta metodología en comparación al grupo de retardo de colgajo y grupo control en colgajos cutáneos aleatorizados en ratas. Métodos. Obtuvimos las células madre de tejido graso ínguino-abdominal de ratas adultas: 10 en el grupo de células madre derivadas de tejido adiposo y otras 10 en el grupo de células madre derivadas de tejido adiposo precondicionadas con hipoxia (2% O2 y 5% CO2). Realizamos análisis morfológico directo y con inmunofluorescencia con el marcador vimentina y CD90 y estudio de proliferación y migración celular in vitro. Resultados: Utilizamos en promedio 1.64 +/- 1.13 gr de tejido adiposo en el grupo sin precondicionamiento y 0.93 +/- 0.34 gr en el grupo con precondicionamiento con hipoxia para el aislamiento. Las células madre derivadas de tejido adiposo precondicionadas con hipoxia presentaron un aumento de la capacidad migratoria a las 24 horas de 2.44 +/- 0.85 mm frente a 2.24 +/- 0.82 mm (p ≤ 0.01) y proliferativa 5.42 x105 +/- 1.03 x105 céls/ml frente a 3.26 x105 +/- 8.61 x104 céls/ml) (p ≤ 0.001) de forma significativa en comparación a las sin precondicionamiento. Conclusiones. Describimos en detalle un método de precondicionamiento de células madre mediante hipoxia. Logramos potenciar el efecto de las células madre aumentando en forma significativa su capacidad migratoria y proliferativa de forma precoz

Background and objective. Stem cells are therapeutic candidates for a wide range of diseases. They are of great interest in Plastic Surgery for the management of chronic wounds, adipose tissue transfer and flaps. The objective of this study is to describe the method of isolation, culture and characterization of stem cells derived from adipose tissue and how these can be preconditioned with hypoxia and generate in vitro changes in their proliferative and migratory capacity. This study is a didactic supplement to a paper published by us in this same journal using this methodology in comparison to the group of flap delay and control group in skin flaps randomized in rats. Methods. Stem cells were obtained from inguinal-abdominal fatty tissue of adult rats: 10 in the group of stem cells derived from adipose tissue and another 10 in the group of stem cells derived from adipose tissue preconditioned with hypoxia (2% O2 and 5% CO2). Direct morphological analysis was carried out and with immunofluorescence (vimentin and CD90 marker). Study proliferation and in vitro cell migration was performed. Results. An average of 1.64 +/- 1.13 gr of adipose tissue of the inguinoabdominal area was used in the group of stem cells without preconditioning and 0.93 +/- 0.34 gr. in the group with hypoxic preconditioning for the isolation. Stem cells derived from adipose tissue preconditioned with hypoxia showed an increase in migratory capacity at 24 hours of 2.44 +/- 0.85 mm v/s 2.24 +/- 0.82 mm (p ≤ 0.01) and proliferative of 5.42 x105 +/- 1.03 x105 cells / ml v/s 3.26 x 105 +/- 8.61 x104 cells / ml) (p ≤0.001) significantly compared to those without preconditioning. Conclusions. A method of preconditioning stem cells by hypoxia is described in detail. It is possible to enhance the effect of the stem cells, significantly increasing their early migratory and proliferative capacity

Especialidades derivadas de la cirugía general: revisión de brechas e intención de residentes de la especialidad en Chile / Gaps between country needs and intentions to obtain a subspecialty among general surgery trainees in Chile

The fragmentation of a general specialty in subspecialties or derived specialties is a widely spread reality. Chilean health care system is becoming more complex, requiring more specialists. On the other hand, doctors in specialty training increasingly choose a subspecialty to continue their training and professional development. This contrasts with the growing need for well-trained general surgeons. We aimed to compare the evidence about the needs for general surgeons and the perspectives of Chilean physicians about their specialty training. A literature review about the intention of specialization in Chilean general surgery residents and the gaps in the Chilean health system, was performed. As of December 2016, there were 2,103 general surgeons in Chile, of whom 598 (28%) also have a subspecialty. Among the latter, 49% are plastic or vascular surgeons, which are also the specialties with the greatest demand in the public system. According to estimates of the Chilean Ministry of Health, on that year there was a deficit of 285 general surgeons and 142 subspecialists. These figures correspond to 18.5% and 23.8% of the existing resources. A survey published in 2009 reported that 78% of trainees in general surgery would prefer to continue studying a subspecialty, following the trend observed in the USA and Europe. Therefore, there is a disproportion between the intentions of general surgery trainees and the needs for these professionals in Chile.

Clasificación y grado de necrosis en colgajo cutáneo aleatorio en ratas tras tratamiento con células madre precondicionadas con hipoxia y retardo del colgajo / Classification and score of necrosis in random skin flap in rats after treatment with transplantation of hypoxia preconditioned adipose-derived stem cells and flap delay

Introducción y Objetivo: Realizar una clasificación de necrosis en colgajos cutáneos aleatorios (predispuesto a necrosis) según los hallazgos macroscópicos e histopatológicos, con o sin tratamiento para aumentar la supervivencia del colgajo, podría ser útil para analizar de forma global el colgajo y evaluar distintas modalidades para disminuir la necrosis. Nuestro objetivo es evaluar si existe más de un patrón de necrosis cutánea del colgajo cutáneo aleatorio al séptimo día de postoperatorio realizando una clasificación de necrosis y comparar la efectividad de los métodos de retardo del colgajo y células madres derivadas de tejido adiposo (ASCs) con y sin precondicionamiento para aumentar la supervivencia del colgajo. Material y Método: Utilizamos 40 ratas macho adultas sometidas a colgajo cutáneo aleatorio en el área dorsal de 2 x 8 cm agrupadas en control, RTC (retardo del colgajo), ASCs y ASCs-H (células madre derivadas de tejido adiposo precondicionadas con hipoxia). Realizamos cálculo del área, puntuación de necrosis y estudio histológico de los colgajos al séptimo día con hematoxilina-eosina, inmunohistoquímica con VEGF (factor de crecimiento endotelial vascular) y cuantificación del colágeno tipo I y III. Resultados: Según la clasificación, el tipo 0 fue considerado como piel normal; tipo 0+ con cambio adaptativo reversible; tipo 1 necrosis menor con inflamación superficial; tipo 2 necrosis menor con inflamación profunda; y finalmente el tipo 3 necrosis en su grado máximo. La piel sana mantiene la coloración y textura elástica y blanda. A medida que progresa la necrosis cambia hacia un tono más oscuro, y la textura y consistencia van aumentando hasta tornarse acartonada y delgada. En los tipos 0+ y 1 observamos focos de reepitelización temprana al séptimo día, mientras que en estadios más avanzados la necrosis fue completa. El grupo de RTC presenta una menor puntuación y por lo tanto necrosis de menor grado respecto al resto de los grupos tratados. Por otra parte, el porcentaje global de necrosis fue menor en los grupos tratados con ASCs y ASCs-H respecto al grupo control (p ≤ 0.05). Conclusiones: La clasificación y puntuación de necrosis parece ser un método adecuado para comprender la evolución de la necrosis del colgajo cutáneo aleatorio y como herramienta para investigación. La necrosis de bajo grado permitiría un afrontamiento conservador y expectante respecto a la de mayor grado. El grupo RTC presentó un puntuación menor al séptimo día con mayor capacidad de reepitelización, mientras que los tratamientos con ASCs y ASCs-H lograron una menor área de necrosis de forma global al séptimo día

Background and Objective: Perform a characterization and classification of necrosis in random skin flaps (predisposed to necrosis) according to the macroscopic and histopathological findings, with or without treatment to increase the survival of the flap, it could be useful to analyze in a global way the flap and evaluate different modalities for decrease necrosis. Our aim is to evaluate if there is more than one skin cutaneous necrosis pattern of the random cutaneous flap on the seventh postoperative day, performing a necrosis classification and to compare the effectiveness of the flap delay and adipose tissue derived stem cells (ASCs) with and without preconditioning methods to increase the survival of the flap. Methods: Forty adult male rats subjected to random skin flap in the dorsal area of 2 x 8 cm grouped into control group, RTC (flap delay), ASCs (adipose-derived stem cells) and ASCs-H (hypoxic preconditioning of adipose-derived stem cells), were used. Area calculation, necrosis score and histological study of flaps on the seventh day with hematoxylin-eosin, immunohistochemistry with VEGF (vascular endothelial growth factor) and quantification of type I and III collagen were performed. Results: According to the classification of necrosis, type 0 was considered normal skin; type 0+ with reversible adaptive change; type 1 minor necrosis with superficial inflammation; type 2 minor necrosis with deep inflammation; and finally type 3 necrosis in its maximum degree. Healthy skin maintains coloring, elastic and soft texture. As necrosis progresses shifts towards a darker tone, texture and consistency increases until it becomes stiff and thin. In types 0+ and 1, foci of early reepithelialization was observed on the seventh day, while more advanced in the classification stages, necrosis is complete. The group of RTC presents a lower score and therefore lesser degree of necrosis with respect to the rest of the treated groups. Moreover the overall percentage of necrosis was lower in the groups treated with ASCs and ASCs-H in the control group (p ≤ 0.05). Conclusions: The classification and the score of necrosis seems to be a suitable method for understanding the evolution of skin flap necrosis and as a tool for research. Low-grade necrosis allows conservative and expectant confrontation with respect to higher grades. The RTC group presented a lower necrosis score on the seventh day with greater reepithelialization capacity, whereas treatment with ASCs and ASCs-H achieved a lower area of necrosis overall on the seventh day

[Gaps between country needs and intentions to obtain a subspecialty among general surgery trainees in Chile]. / Especialidades derivadas de la cirugía general: revisión de brechas e intención de residentes de la especialidad en Chile.

The fragmentation of a general specialty in subspecialties or derived specialties is a widely spread reality. Chilean health care system is becoming more complex, requiring more specialists. On the other hand, doctors in specialty training increasingly choose a subspecialty to continue their training and professional development. This contrasts with the growing need for well-trained general surgeons. We aimed to compare the evidence about the needs for general surgeons and the perspectives of Chilean physicians about their specialty training. A literature review about the intention of specialization in Chilean general surgery residents and the gaps in the Chilean health system, was performed. As of December 2016, there were 2,103 general surgeons in Chile, of whom 598 (28%) also have a subspecialty. Among the latter, 49% are plastic or vascular surgeons, which are also the specialties with the greatest demand in the public system. According to estimates of the Chilean Ministry of Health, on that year there was a deficit of 285 general surgeons and 142 subspecialists. These figures correspond to 18.5% and 23.8% of the existing resources. A survey published in 2009 reported that 78% of trainees in general surgery would prefer to continue studying a subspecialty, following the trend observed in the USA and Europe. Therefore, there is a disproportion between the intentions of general surgery trainees and the needs for these professionals in Chile.