TGF-ß loaded exosome enhances ischemic wound healing in vitro and in vivo.

Rationale: With over seven million infections and $25 billion treatment cost, chronic ischemic wounds are one of the most serious complications in the United States. The controlled release of bioactive factor enriched exosome from finbrin gel was a promising strategy to promote wound healing. Methods: To address this unsolved problem, we developed clinical-grade platelets exosome product (PEP), which was incorporate with injectable surgical fibrin sealant (TISSEEL), to promote chronic wound healing and complete skin regeneration. The PEP characterization stimulated cellular activities and in vivo rabbit ischemic wound healing capacity of TISSEEL-PEP were performed and analyzed. Results: PEP, enriched with transforming growth factor beta (TGF-ß), possessed exosomal characteristics including exosome size, morphology, and typical markers including CD63, CD9, and ALG-2-interacting protein X (Alix). In vitro, PEP significantly promoted cell proliferation, migration, tube formation, as well as skin organoid formation. Topical treatment of ischemic wounds with TISSEEL-PEP promoted full-thickness healing with the reacquisition of hair follicles and sebaceous glands. Superior to untreated and TISSEEL-only treated controls, TISSEEL-PEP drove cutaneous healing associated with collagen synthesis and restoration of dermal architecture. Furthermore, PEP promoted epithelial and vascular cell activity enhancing angiogenesis to restore blood flow and mature skin function. Transcriptome deconvolution of TISSEEL-PEP versus TISSEEL-only treated wounds prioritized regenerative pathways encompassing neovascularization, matrix remodeling and tissue growth. Conclusion: This room-temperature stable, lyophilized exosome product is thus capable of delivering a bioactive transforming growth factor beta to drive regenerative events.

Arterial only anastomosis associated with modified Baudet technique in ear replantation: Case reports and literature review.

BACKGROUND: Total ear amputation is a relatively rare trauma with an absolute indication for surgical treatment. Numerous techniques for auricular reconstruction have been described. When local and general conditions allow microsurgical replantation, this must be the first choice. We propose the association of microsurgical techniques with some modification (modified Baudet technique) to obtain higher survival rate of the reimplanted stump. METHODS: This study included cases of 3 male patients with total ear amputation, the injuries and their mechanism (workplace accident) being identical. Chief complaints were pain, bleeding, important emotional impact due by an unaesthetic appearance. The established diagnosis was traumatic complete ear amputation (grade IV auricular injury according to Weerda classification). Microsurgical replantation was performed only with arteriorraphy, and no vein anastomosis. Cartilage incisions and skin excisions were made to enlarge the cartilage-recipient site contact area. Medicinal leeches were used to treat venous congestion, to which systemic anticoagulant therapy was added. RESULTS: The results showed the survival of the entire replanted segment in all cases, with good function and esthetical appearance. Patients were fully satisfied with the final outcome. CONCLUSION: Microsurgical replantation is the gold standard, for the surgical treatment of total ear amputation. We believe that cartilage incisions and the increased surface of contact between cartilage and recipient site has an adjuvant role in revascularization of the amputated stump (with only arterial anastomosis) and the use of hirudotherapy helps to relieve early venous congestion.

Image-guided simulation in comparison with laser speckle contrast imaging for full-field observation of blood flow in a microvasculature model.

The in vitro reconstruction of the microvascular network model provides a reproducible platform for hemodynamic study with great biological relevance. In the present study, microvascular models with different parametric features were designed under the guidance of Murray's law and derived from representative natural vascular network topography in vivo. Computational fluid dynamics (CFD) was used to numerically simulate blood velocity distributions inside of the designed microvasculature models. Full-field blood flow in the vascular network was visualized in vivo using a laser speckle contrast imaging (LSCI) system, from which the measured relative velocity was compared with CFD computed flow distribution. The results have shown that, in comparison with the simplified flow patterns obtained from idealized geometries, the irregular vascular topography is expected to lead to nonuniform and poor regional blood velocity distribution. The velocity distribution acquired by in vivo LSCI experiment is in good agreement with that of numerical simulation, indicating the technical feasibility of using biomimetic microchannels as a reasonable approximation of the microcirculatory flow conditions. This study provides a new paradigm that can be well suited to the study of microvascular blood flow properties and can further expand to mimic other in-vivo scenarios for accurately recapitulating the physical and hemodynamic environment of the microcirculation.

Comparative Effectiveness of Different Interventions of Perivascular Hyaluronidase.

BACKGROUND: Soft-tissue necrosis caused by vascular compromise is a frequent and troublesome complication of hyaluronic acid filler injection. Hyaluronidase has been proposed as a treatment for this condition. This study aimed to determine the effective dose and administration interval of hyaluronidase injection in a skin necrosis animal model. METHODS: New Zealand rabbits were used to simulate the hyaluronic acid-associated vascular occlusion model. Hyaluronic acid filler (0.1 ml) was injected into the central auricular artery to create an occlusion. Three rabbit auricular flaps were injected with 500 IU of hyaluronidase once (group A) and three flaps each were injected at 15-minute intervals with 250 IU of hyaluronidase twice (group B), 125 IU of hyaluronidase four times (group C), 100 IU of hyaluronidase five times (group D), and 75 IU of hyaluronidase seven times (group E), all at 24 hours after occlusion. No intervention was administered after occlusion in the control group. Flap fluorescence angiography was performed immediately after hyaluronidase injection and on postoperative days 2, 4, and 7. Flap necrotic areas were analyzed. RESULTS: All control and experimental flaps demonstrated total occlusion after hyaluronic acid injection. The average total survival rate (positive area/total area ×100 percent) of control flaps was 37.61 percent. For experimental groups, the average total survival rates were 74.83 percent, 81.49 percent, 88.26 percent, 56.48 percent, and 60.69 percent in groups A through E, respectively. CONCLUSION: A better prognosis can be obtained by administering repeated doses rather than a single high dose of hyaluronidase.

Management of arteriovenous malformation of the ear: A protocol for resection and reconstruction.

OBJECTIVE: Arteriovenous malformations (AVM) of the ear show unique features. Progressive growth or inadequate management of AVMs may lead to bleeding, infection, cartilage exposure, and ultimately loss of structure. Total ear amputation is an alternative; however, due to the structural complexity of the ear, reconstruction is technically challenging. This study presents a treatment algorithm based on a clinical series, with treatment options including resection and immediate and late reconstruction. METHODS: Between 2004 and 2018, 12 patients with auricular AVMs were treated with AVM resection and ear reconstruction at our hospital. Among these 12 patients, seven were women, and patients' ages ranged between 4 and 34 years. Parameters considered before resection and reconstruction were compromised ear extension (partial, total, or extra-auricular involvement), thickness (cutaneous and cartilaginous), symptoms (bleeding, infection, ulceration, and/or cartilage exposure), and preoperative embolization. Total resection of AVMs was planned as the first step in all cases, followed by primary closure. AVM resection was categorized into a partial or total procedure, resulting in partial or total ear defects. Reconstruction was categorized as immediate or delayed. RESULTS: Preoperative embolization was performed in 10 patients. AVMs were totally removed, resulting in seven total ear amputations. In six of these patients, total ear reconstruction was performed 6 months later, and all patients were recurrence-free. Only one patient did not undergo ear reconstruction. Regrowth was not observed in any reconstructed ear. CONCLUSION: Treatment of ear AVMs requires a planned approach to achieve favorable clinical outcomes and for concomitant safe and definitive reconstruction. LEVEL OF EVIDENCE: 4 Laryngoscope, 130:1322-1326, 2020.

Analysis In Vivo of the Hemifacial Transplantation Surgical Technique.

Approximately 35 facial transplants have been performed worldwide. Many under-explored aspects of this procedure remain, some emerging as the survivors age. Human-like preclinical trial models, including swine, can be explored and developed as a foundation for subsequent studies. A previously described surgical technique for face transplantation in swine carcasses has been employed herein, evaluating its reproducibility in a live pig and the viability of the vascular pedicles. METHOD: Flap construction was performed according to the experimental model developed in our service. Under general anesthesia, the structures of the left hemiface of a pig were dissected. Vascular pedicles were the facial artery, caudal auricular artery, and external jugular vein. After dissection, adequate tissue perfusion of the entire explant by those pedicles was documented through vessel filling, observation of the ischemic area, and posterior reperfusion. RESULTS: A capillary reperfusion test confirmed that the main arterial pedicle irrigating the hemiface flap was the facial artery. The same technique showed that despite divergent literary opinions on the irrigation of the auricular region, the caudal auricular artery provides the arterial supply for the external ear. Performing the surgical technique was more difficult in vivo due to the inherent complications of a live subject. CONCLUSION: The methodology for the facial transplant technique in swine carcasses was satisfactorily reproducible in a live animal. The main arterial pedicle responsible for flap irrigation is the facial artery, and the fact that the vessel supplying the outer ear is the caudal atrial artery was confirmed.

Parametric standing wave generation of a shallow reflection plane in a nonrigid sample for use in a noninvasive blood glucose monitor.

When monitoring a moist sample using mid-infrared spectroscopy, its thickness must be <100 µm to avoid light absorption from the water. Therefore, we propose an ultrasonic-assisted mid-infrared spectroscopic imaging method that can generate a reflection plane at a depth of 100 µm from the surface of the sample by creating an ultrasonic standing wave. A frequency of 10 MHz is required to obtain an optical path length of 100 µm in biological samples. However, because biological samples generally have high compressibility, attenuation of ultrasonic waves at this frequency is significant. We use agar as a biological phantom and observe that a reflection plane is generated inside by ultrasonic standing waves using optical coherence tomography. It is found that when the sample is vibrated with an 800-kHz ultrasonic wave, a reflection plane is generated at a depth shallower than the theoretically predicted value. We believe that the reflection plane is generated by parametric standing waves, which are based on parametric effect. We detect the waveform distortion using an acoustic emission sensor and confirm the higher harmonics that generate the observed reflection plane using a fast Fourier transform.

Anatomy of the superficial temporal artery in patients with unilateral microtia.

BACKGROUND: This retrospective study evaluated the anatomical distribution of the superficial temporal artery (STA) in supply of the temporoparietal fascial (TPF) flap for use in patients with unilateral microtia undergoing reconstruction. We aimed to determine whether embryologic arrest of pharyngeal arch development would lead to aberrant STA, which impedes reliable harvest of the TPF flap in patients requiring microtia repair. METHODS: CT angiograms (CTAs) and 3D reconstruction of the face and neck of 41 patients with microtia, aged 6-21 years, were examined. The number of STA branches, branching pattern, vessel diameter, and the presence or absence of the external auditory canal atresia were documented. RESULTS: The STA crosses the zygoma on average 4 mm more anterior to the porion (anterior-inferior lip of the tympanic part of the temporal bone) on the side with microtia compared to the nonmicrotia side. There were no statistically significant differences between vessel caliber or STA branches between the two sides. CONCLUSION: The STA is anatomically reliable for inclusion in TPF flaps, which is used for auricular reconstruction in patients with microtia. A TPF flap can be safely harvested by the routine technique; however, surgeons should be cognizant of the STA coursing more anteriorly on the microtia ear.

Midterm and long-term results of ethanol embolization of auricular arteriovenous malformations as first-line therapy.

OBJECTIVE: The objective of this study was to assess the midterm and long-term results of patients with auricular arteriovenous malformations (AVMs) treated by ethanol embolization. METHODS: Medical records of 35 patients (20 male, 15 female; age range, 10-59 years) with auricular AVMs between 2006 and 2016 were reviewed. The short-term results of 4 of the 35 patients were reported in 2009. They were included in this study with updated follow-up data. The data from the 31 new included patients have not been reported previously. Ethanol embolization was performed with a direct puncture approach. The nidus was eradicated by bolus injection of ethanol with manual compression whenever possible. Treatment outcomes were classified into four categories by assessing the resolution of symptoms as well as the degree of nidus devascularization between the baseline and follow-up angiography studies. RESULTS: A total of 86 embolization sessions were performed in 35 patients (mean, 2.5 ± 1.3 sessions). The dosage of ethanol used per single session was 12.0 ± 4.5 mL (range, 6.0-24 mL). All patients received post-treatment clinical follow-up (mean, 40.7 ± 25.8 months), and 28 patients received post-treatment imaging follow-up (mean, 34.3 ± 25.5 months). Ethanol embolotherapy was effective in all patients. Control was achieved in 16 patients (45.7%), and improvement was achieved in 18 patients (51.4%). One patient experienced recurrence. A total of 13 minor complications and 2 major complications occurred in 12 patients during the 86 treatment sessions (12/35 [34.2%]; 15/86 [17.4%]). All the complications resolved spontaneously. CONCLUSIONS: The midterm and long-term results of this study demonstrate that ethanol embolization alone is an effective option for auricular AVMs as first-line therapy with a mild risk of minor and major complications.

Angiolymphoid hyperplasia of external ear treated with intralesional radiofrequency ablation.

A 21-year-old woman presented with multiple erythematous to skin-coloured dome-shaped firm papules and plaques over the right ear concha and external auditory canal for 1 year. It was associated with occasional itching and bleeding. Her main concern was cosmetic disfigurement. Biopsy showed presence of multiple proliferating blood vessels lined by plump epithelioid endothelial cells surrounded by dense infiltrate of lymphocytes, histiocytes and eosinophils. Other routine investigations were within normal limits. A diagnosis of angiolymphoid hyperplasia with eosinophilia was made. A single sitting of intralesional radiofrequency ablation (Vesalius, coagulation mode; fanning technique) using 18-G intravenous cannula was done. This led to almost complete resolution with no recurrence at 3 months follow-up. There was no evidence of scarring or depigmentation.

Miniature probe for in vivo optical- and acoustic-resolution photoacoustic microscopy.

We present a miniature probe capable of both optical-resolution (OR) and acoustic-resolution (AR) photoacoustic microscopy. A gradient-index-lens fiber and a multimode fiber are used to deliver light for OR and AR illumination, respectively. The probe achieves lateral resolution of 3.1 µm for OR mode and 46-249 µm (at depth of 1.2-4.3 mm) for AR mode, respectively. The size of the probe attains 3.7 mm in diameter, which can be used for endoscopic applications. In vivo imaging of several different parts of a mouse demonstrates the excellent imaging ability of the probe.

The Hybrid Technical Management of Large and Complicated Traumatic Arteriovenous Fistula of Preauricular Region.

BACKGROUND: Arteriovenous fistula (AVF) is defined as an abnormal communication between the high flow arterial system and the low flow venous network, which directly connects the arterial feeding vessels and the near draining veins without normal intervening capillary bed. Arteriovenous fistula incurs in preauricular region is exceeding rare. Most of these fistulae occur as a result of an iatrogenic injury, the volume is small, feeding and draining vessels of feeding and draining are simple, and can be cured easily. However, the treatment of the large and complicated AVF after incidental trauma in preauricular region is a challenge even for senior neurosurgeon. In this study, the authors discuss the management of a traumatic AVF through combined therapeutic method of surgical ligation and transarterial embolization. It is fed by ipsilateral superficial temporal artery, internal maxillary artery, posterior auricular artery, and their accessory branches and is drained by ipsilateral common facial vein and external jugular vein. Also the etiology, clinical manifestations, pathology, diagnosis, and management are summarized. CONCLUSION: Large and complicated traumatic AVF in preauricular region is rare, often due from an injury in maxillofacial region, combined therapy needed.

Intravital Microscopy and Thrombus Induction in the Earlobe of a Hairless Mouse.

Thrombotic complications of vascular diseases are one leading cause of morbidity and mortality in industrial nations. Due to the complex interactions between cellular and non-cellular blood components during thrombus formation, reliable studies of the physiology and pathophysiology of thrombosis can only be performed in vivo. Therefore, this article presents an ear model in hairless mice and focuses on the in vivo analysis of microcirculation, thrombus formation, and thrombus evolution. By using intravital fluorescence microscopy and the intravenous (iv) application of the respective fluorescent dyes, a repetitive analysis of microcirculation in the auricle can easily be performed, without the need for surgical preparation. Furthermore, this model can be adapted for in vivo studies of different issues, including wound healing, reperfusion injury, or angiogenesis. In summary, the ear of hairless mice is an ideal model for the in vivo study of skin microcirculation in physiological or pathophysiological conditions and for the evaluation of its reaction to different systemic or topical treatments.

Evaluation of the effects of intra-arterial sugammadex and dexmedetomidine: an experimental study / Avaliação dos efeitos de sugamadex e dexmedetomidina intra-arterial: estudo experimental

Abstract Background: Intra-arterial injection of medications may cause acute and severe ischemia and result in morbidity and mortality. There is no information in the literature evaluating the arterial endothelial effects of sugammadex and dexmedetomidine. The hypothesis of our study is that sugammadex and dexmedetomidine will cause histological changes in arterial endothelial structure when administered intra-arterially. Methods: Rabbits were randomly divided into 4 groups. Group Control (n = 7); no intervention performed. Group Catheter (n = 7); a cannula inserted in the central artery of the ear, no medication was administered. Group Sugammadex (n = 7); rabbits were given 4 mg/kg sugammadex into the central artery of the ear, and Group Dexmedetomidine (n = 7); rabbits were given 1 µg/kg dexmedetomidine into the central artery of the ear. After 72 h, the ears were amputated and histologically investigated. Results: There was no significant difference found between the control and catheter groups in histological scores. The endothelial damage, elastic membrane and elastic fiber damage, smooth muscle hypertrophy and connective tissue increase scores in the dexmedetomidine and sugammadex groups were significantly higher than both the control and the catheter groups (p < 0.05). There was no significant difference found between the dexmedetomidine and sugammadex groups in histological scores. Conclusion: Administration of sugammadex and dexmedetomidine to rabbits by intra-arterial routes caused histological arterial damage. To understand the histological changes caused by sugammadex and dexmedetomidine more clearly, more experimental research is needed.

Resumo Justificativa: A injeção intra-arterial de medicamentos pode causar isquemia aguda e grave e resultar em morbidade e mortalidade. Não há informações na literatura que avaliem os efeitos endoteliais arteriais de sugamadex e dexmedetomidina. A hipótese de nosso estudo foi que dexmedetomidina e sugamadex causariam alterações histológicas na estrutura endotelial arterial quando administrados por via intra-arterial. Método: Os coelhos foram randomicamente divididos em quatro grupos: grupo controle (n = 7), sem intervenção; grupo cateter (n = 7), uma cânula foi inserida na artéria central da orelha e medicamentos não foram administrados; grupo sugamadex (n = 7), receberam 4 mg/kg de sugamadex na artéria central da orelha; grupo dexmedetomidina (n = 7), receberam 1 µg/kg de dexmedetomidina na artéria central da orelha. Após 72 horas, as orelhas foram amputadas e histologicamente examinadas. Resultados: Não houve diferença significativa entre os grupos controle e cateter referente aos escores histológicos. Os escores do dano causado ao endotélio e à membrana e fibra elásticas, da hipertrofia do músculo liso e do aumento do tecido conjuntivo foram significativamente maiores nos grupos dexmedetomidina e sugamadex do que nos grupos controle e cateter (p < 0,05). Não houve diferença significativa entre os grupos dexmedetomidina e sugamadex nos escores histológicos. Conclusão: A administração de sugamadex e dexmedetomidina a coelhos por via intra-arterial causou danos arteriais histológicos. Para entender as alterações histológicas causadas por sugamadex e dexmedetomidina com mais clareza, estudos experimentais adicionais são necessários.

Evaluation of the effects of intra-arterial sugammadex and dexmedetomidine: an experimental study.

BACKGROUND: Intra-arterial injection of medications may cause acute and severe ischemia and result in morbidity and mortality. There is no information in the literature evaluating the arterial endothelial effects of sugammadex and dexmedetomidine. The hypothesis of our study is that sugammadex and dexmedetomidine will cause histological changes in arterial endothelial structure when administered intra-arterially. METHODS: Rabbits were randomly divided into 4 groups. Group Control (n=7); no intervention performed. Group Catheter (n=7); a cannula inserted in the central artery of the ear, no medication was administered. Group Sugammadex (n=7); rabbits were given 4mg/kg sugammadex into the central artery of the ear, and Group Dexmedetomidine (n=7); rabbits were given 1µg/kg dexmedetomidine into the central artery of the ear. After 72h, the ears were amputated and histologically investigated. RESULTS: There was no significant difference found between the control and catheter groups in histological scores. The endothelial damage, elastic membrane and elastic fiber damage, smooth muscle hypertrophy and connective tissue increase scores in the dexmedetomidine and sugammadex groups were significantly higher than both the control and the catheter groups (p<0.05). There was no significant difference found between the dexmedetomidine and sugammadex groups in histological scores. CONCLUSION: Administration of sugammadex and dexmedetomidine to rabbits by intra-arterial routes caused histological arterial damage. To understand the histological changes caused by sugammadex and dexmedetomidine more clearly, more experimental research is needed.

Absence of skin discoloration after transarterial embolization of a subcutaneous auricular arteriovenous malformation with PHIL.

BACKGROUND AND OBJECTIVE: One of the treatment options for arteriovenous malformations consists of embolization, with a choice of various embolic agents, with or without subsequent surgical excision. If embolization is offered without subsequent surgery, the embolic material will stay in situ, in which case the consistency and color become important in superficial lesions. The purpose of this case report is to describe if the use of a novel liquid embolic agent (PHIL) is well suited for treatment of superficial AVMs without subsequent surgery. CASE DESCRIPTION: A 30-year-old male presented with a painful reddish, pulsatile swelling of the left ear that had been present for more than 10 years. Angiography confirmed an arteriovenous malformation supplied by the superficial temporal artery and the posterior auricular artery. The lesion was successfully treated by embolization with PHIL, through the superficial temporal artery. A minute residual shunt, from the posterior auricular artery, was accepted. Immediate disappearance of pulsatile tinnitus was reported. Moreover, return of normal skin color was observed without discomfort from the embolic deposits. This result has been stable throughout one year of clinical follow-up. CONCLUSION: To our knowledge, this is the first case report describing PHIL embolization as a treatment option for superficial arteriovenous malformations without the necessity for subsequent surgery. The white color and rubbery consistency are beneficial characteristics of PHIL in treatment of subcutaneous lesions, especially in cosmetically relevant locations.

Microsurgical ear replantation-is venous repair necessary?-A systematic review.

BACKGROUND: A common postoperative observation after microsurgical ear replantation has been venous congestion necessitating alternate modes of decongestion, frequently in conjunction with blood transfusion. A comprehensive literature search was performed to assess the relationship between mode of vascular reconstruction and postoperative outcome as well as postoperative transfusion requirement after microsurgical ear replantation. METHODS: The search was limited to cases of microsurgical ear replantation following complete amputation. Only articles published in English and indexed in PubMed were included. RESULTS: The initial search retrieved 285 articles, which was narrowed down to 40 articles reporting on 60 cases that matched the aforementioned criteria. Reconstruction of the arterial and venous limb (Group 1) was performed in 63.3% of patients and artery-only anastomosis (Group 2) was performed in 31.7%. Among measurable outcomes, only the duration of surgery was significantly different between groups (2.6 hours longer in Group 1 than Group 2; P = 0.0042). CONCLUSION: In light of contemporary data demonstrating successful artery-only ear replantation, replantation should not be abandoned when unable to establish venous outflow microsurgically. © 2015 Wiley Periodicals, Inc. Microsurgery 36:345-350, 2016.

[STUDYING OF BIOMECHANICAL PROPERTIES OF SKIN IN THE MASTOID REGION WHILE THE COSMETIC OTOPLASTY PERFORMANCE].

The present methods for a droopy ears correction do not guarantee the optimal cosmetic effect achievement. Optimal borders of deformity in cutaneo-adiposal flap of the mastoid region while cosmetic otoplasty performance were studied. Basing on analysis of biomechanical investigations, there were determined the optimal corners of stretching and direction of the strength vector in cutaneo-adiposal flaps while otoplasty performance, securing conditions for surgical intervention performance with preservation of a natural topographo-anatomical ratios in the head and neck tissues.