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1.
Nano Lett ; 23(16): 7675-7682, 2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37578323

RESUMO

The interplay of spin-orbit coupling and crystal symmetry can generate spin-polarized bands in materials only a few atomic layers thick, potentially leading to unprecedented physical properties. In the case of bilayer materials with global inversion symmetry, locally broken inversion symmetry can generate degenerate spin-polarized bands, in which the spins in each layer are oppositely polarized. Here, we demonstrate that the hidden spins in a Tl bilayer crystal are revealed by growing it on Ag(111) of sizable lattice mismatch, together with the appearance of a remarkable phenomenon unique to centrosymmetric hidden-spin bilayer crystals: a novel band splitting in both spin and space. The key to success in observing this novel splitting is that the interaction at the interface has just the right strength: it does not destroy the original wave functions of the Tl bilayer but is strong enough to induce an energy separation.

2.
Chem Rec ; 23(8): e202300045, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37098877

RESUMO

Recently, electronic devices that make use of a state called the electric double layers (EDL) of ion have opened up a wide range of research opportunities, from novel physical phenomena in solid-state materials to next-generation low-power consumption devices. They are considered to be the future iontronics devices. EDLs behave as nanogap capacitors, resulting the high density of charge carriers is induced at semiconductor/electrolyte by applying only a few volts of the bias voltage. This enables the low-power operation of electronic devices as well as new functional devices. Furthermore, by controlling the motion of ions, ions can be used as semi-permanent charge to form electrets. In this article, we are going to introduce the recent advanced application of iontronics devices as well as energy harvesters making use of ion-based electrets, leading to the future iontronics research.

3.
Wound Repair Regen ; 30(4): 453-467, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35567569

RESUMO

There are two types of pressure injuries: self-load-related pressure injuries (PIs) and medical device-related pressure injuries (MDRPIs), but the differences in risk factors between PIs and MDRPIs have not yet been clarified. If risk factors for PIs and MDRPIs differ, preventive interventions should take this into account. This is a prospective cohort study aimed to determine the cumulative incidence of PIs and MDRPIs in critically ill patients and to identify corresponding risk factors. The study included 1418 patients who were admitted to the critical care medical center of a single university hospital in Tokyo, Japan, between 1 December 2019 and 31 August 2020. The Kaplan-Meier method was used to calculate the cumulative incidence of PIs and MDRPIs. Furthermore, the Cox proportional hazards model was used to analyse the predictors in both the PI and MDRPI incidence and non-incidence groups. Predictors were based on data from the 0th disease day. The cumulative incidence of PIs and MDRPIs was 4.6/1000 person-days and 3.6/1000 person-days, respectively. Multivariate analysis using the Cox proportional hazards model showed that common risk factors for the occurrence of PIs and MDRPIs were possession of PI on admission, higher blood lactate, blood purification therapy, and positional restriction. The risk factors for PIs only were diabetes mellitus, septic shock, and a lower serum albumin level, while the risk factors for MDRPIs only were the D-dimer level and extracorporeal membranous oxygenation treatment. Therefore, prophylactic interventions need to consider these different risk factors.


Assuntos
Estado Terminal , Úlcera por Pressão , Humanos , Incidência , Úlcera por Pressão/epidemiologia , Úlcera por Pressão/etiologia , Úlcera por Pressão/prevenção & controle , Estudos Prospectivos , Fatores de Risco , Cicatrização
4.
Proc Natl Acad Sci U S A ; 113(23): 6438-43, 2016 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-27222585

RESUMO

Control of dimensionality has proven to be an effective way to manipulate the electronic properties of materials, thereby enabling exotic quantum phenomena, such as superconductivity, quantum Hall effects, and valleytronic effects. Another example is thermoelectricity, which has been theoretically proposed to be favorably controllable by reducing the dimensionality. Here, we verify this proposal by performing a systematic study on a gate-tuned 2D electron gas (2DEG) system formed at the surface of ZnO. Combining state-of-the-art electric-double-layer transistor experiments and realistic tight-binding calculations, we show that, for a wide range of carrier densities, the 2DEG channel comprises a single subband, and its effective thickness can be reduced to [Formula: see text] 1 nm at sufficiently high gate biases. We also demonstrate that the thermoelectric performance of the 2DEG region is significantly higher than that of bulk ZnO. Our approach opens up a route to exploit the peculiar behavior of 2DEG electronic states and realize thermoelectric devices with advanced functionalities.


Assuntos
Eletricidade , Óxido de Zinco/química , Elétrons , Gases , Temperatura Alta , Modelos Teóricos , Semicondutores
5.
Sci Technol Adv Mater ; 19(1): 317-323, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29707070

RESUMO

A novel triboelectric energy harvester has been developed using an ionic liquid polymer with cations fixed at the surface. In this report, the fabrication of the device and the characterization of its energy harvesting performance are detailed. An electrical double layer was induced in the ionic liquid polymer precursor to attract the cations to the surface where they are immobilized using a UV-based crosslinking reaction. The finalized polymer is capable of generating an electrical current when contacted by a metal electrode. Using this property, energy harvesting experiments were conducted by cyclically contacting a gold-surface electrode with the charge fixed surface of the polymer. Control experiments verified the effect of immobilizing the cations at the surface. By synthesizing a polymer with the optimal composition ratio of ionic liquid to macromonomer, an output of 77 nW/cm2 was obtained with a load resistance of 1 MΩ at 1 Hz. This tuneable power supply with a µA level current output may contribute to Internet of Things networks requiring numerous sensor nodes at remote places in the environment.

6.
Nature ; 468(7324): 677-80, 2010 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-21124453

RESUMO

Doped Mott insulators have a strong propensity to form patterns of holes and spins often referred to as stripes. In copper oxides, doping also gives rise to the pseudogap state, which can be transformed into a high-temperature superconducting state with sufficient doping or by reducing the temperature. A long-standing issue has been the interplay between the pseudogap, which is generic to all hole-doped copper oxide superconductors, and stripes, whose static form occurs in only one family of copper oxides over a narrow range of the phase diagram. Here we report observations of the spatial reorganization of electronic states with the onset of the pseudogap state in the high-temperature superconductor Bi(2)Sr(2)CaCu(2)O(8+x), using spectroscopic mapping with a scanning tunnelling microscope. We find that the onset of the pseudogap phase coincides with the appearance of electronic patterns that have the predicted characteristics of fluctuating stripes. As expected, the stripe patterns are strongest when the hole concentration in the CuO(2) planes is close to 1/8 (per copper atom). Although they demonstrate that the fluctuating stripes emerge with the onset of the pseudogap state and occur over a large part of the phase diagram, our experiments indicate that the stripes are a consequence of pseudogap behaviour rather than its cause.

7.
Ann Plast Surg ; 77(6): 669-673, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26835831

RESUMO

BACKGROUND: Because the course and territory of perforators are different in each region, careful preoperative planning to identify the proper perforators can be critical to ensure a successful dissection of a freestyle pedicled perforator flap. In this study, our first experience for preoperative perforator mapping of a freestyle pedicled perforator flap using multidetector row computed tomography (MD-CT) angiography is presented. METHODS: Twelve patients were planned to undergo various soft-tissue reconstructions with freestyle pedicled perforator flaps. They were evaluated with preoperative MD-CT angiography. The OsiriX for mac software was used to process the data obtained from MD-CT angiography. The available images from MD-CT angiography were analyzed to determine where the proper perforators were located for preoperative planning of a freestyle pedicled perforator flap. Through the MD-CT angiography, the optimal perforators were mapped and a reliable flap design could be made so that the flap was elevated more safely and perfectly to cover an adjacent soft-tissue defect. RESULTS: In all 12 patients, each flap was elevated successfully based on the perforators mapped preoperatively with MD-CT angiography. A total of 27 perforators (1-3 perforators per flap) were identified by MD-CT angiography in 12 patients and later confirmed during the flap dissection (sensitivity, 100%). CONCLUSIONS: The MD-CT angiography can be a new but very effective imaging modality for preoperative planning of a freestyle pedicled perforator flap surgery. It allows surgeons to accurately select the most appropriate perforators with the shortest intramuscular or suprafascial course preoperatively leading to safer and easier flap dissection.


Assuntos
Angiografia por Tomografia Computadorizada/métodos , Tomografia Computadorizada Multidetectores , Retalho Perfurante/irrigação sanguínea , Procedimentos de Cirurgia Plástica/métodos , Cuidados Pré-Operatórios/métodos , Adolescente , Adulto , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Adulto Jovem
8.
J Clin Med ; 13(5)2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38592344

RESUMO

The essence of treating scar contractures lies in covering the skin deficit after releasing the contractures, typically using flaps or skin grafts. However, the specific characteristics of scar contractures, such as their location, shape, and size, vary among patients, which makes surgical planning challenging. To achieve excellent outcomes in the treatment of scar contractures, we have developed a dimensional classification system for these contractures. This system categorizes them into four types: type 1 (superficial linear), type 2-d (deep linear), type 2-s (planar scar contractures confined to the superficial layer), and type 3 (planar scar contractures that reach the deep layer, i.e., three-dimensional scar contractures). Additionally, three factors should be considered when determining surgical approaches: the size of the defect, the availability of healthy skin around the defect, and the blood circulation in the defect bed. Type 1 and type 2-d are linear scars; thus, the scar is excised and sutured in a straight line, and the contracture is released using z-plasty or its modified methods. For type 2-s, after releasing the scar contracture band, local flaps are indicated for small defects, pedicled perforator flaps for medium defects, and free flaps and distant flaps for large defects. Type 2-s has good blood circulation in the defect bed, so full-thickness skin grafting is also a suitable option regardless of the defect's size. In type 3, releasing the deep scar contracture will expose important structures with poor blood circulation, such as tendons, joints, and bones. Thus, a surgical plan using flaps, rather than skin grafts, is recommended. A severity classification and treatment strategy for scar contractures have not yet been established. By objectively classifying and quantifying scar contractures, we believe that better treatment outcomes can be achieved.

9.
J Burn Care Res ; 45(5): 1325-1330, 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-38938100

RESUMO

This study examines a rare case of frostbite on the hands caused by liquid nitrogen, focusing on the scar maturation process. Frostbite is typically less prone to abnormal scarring compared to burns, and this report contrasts the differences in scar maturation between the two. A 31-year-old male hospital employee sustained first- to second-degree frostbite on his gloved hands from a 20-s exposure to liquid nitrogen while changing a cylinder. Conservative treatment was applied, and the patient was monitored for 9 months. The deeply affected area took 50 days to epithelialize but healed without hypertrophic scarring. A mild extension contracture was noted in the distal interphalangeal joint of the right index finger, but the skin remained supple and soft. Incidents of liquid nitrogen-induced frostbite are uncommon, with only 14 cases reported in PubMed previously. In frostbite, the wound healing involves a slow replacement of damaged connective tissue, which acts as an internal splint, reducing wound contraction. This contrasts with burns, where rapid connective tissue replacement occurs, often leading to significant wound contraction due to the presence of myofibroblasts in granulation tissue. In the presented case, the slow healing process and minimal wound contraction led to mature scarring without abnormalities, underlining a distinctive healing trajectory in frostbite injuries compared to burns.


Assuntos
Congelamento das Extremidades , Traumatismos da Mão , Nitrogênio , Humanos , Congelamento das Extremidades/terapia , Masculino , Adulto , Traumatismos da Mão/terapia , Cicatrização
10.
Nature ; 447(7144): 569-72, 2007 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-17538615

RESUMO

Pairing of electrons in conventional superconductors occurs at the superconducting transition temperature T(c), creating an energy gap Delta in the electronic density of states (DOS). In the high-T(c) superconductors, a partial gap in the DOS exists for a range of temperatures above T(c) (ref. 2). A key question is whether the gap in the DOS above T(c) is associated with pairing, and what determines the temperature at which incoherent pairs form. Here we report the first spatially resolved measurements of gap formation in a high-T(c) superconductor, measured on Bi2Sr2CaCu2O8+delta samples with different T(c) values (hole concentration of 0.12 to 0.22) using scanning tunnelling microscopy. Over a wide range of doping from 0.16 to 0.22 we find that pairing gaps nucleate in nanoscale regions above T(c). These regions proliferate as the temperature is lowered, resulting in a spatial distribution of gap sizes in the superconducting state. Despite the inhomogeneity, we find that every pairing gap develops locally at a temperature T(p), following the relation 2Delta/k(B)T(p) = 7.9 +/- 0.5. At very low doping (< or =0.14), systematic changes in the DOS indicate the presence of another phenomenon, which is unrelated and perhaps competes with electron pairing. Our observation of nanometre-sized pairing regions provides the missing microscopic basis for understanding recent reports of fluctuating superconducting response above T(c) in hole-doped high-T(c) copper oxide superconductors.

11.
Plast Reconstr Surg ; 151(1): 143-147, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36219862

RESUMO

SUMMARY: Intercarpal ligament injuries such as scapholunate and lunotriquetral tears are common causes of wrist pain. There is no shortage of surgical techniques to address these injuries, nor is there a lack of literature exploring this topic. However, research progress has not led to a consensus regarding the optimal management of subacute and chronic injuries without articular wear. The senior author (K.C.C.) has performed the spectrum of reconstructive techniques, including dorsal and volar approaches, tendon weaves, ligament tenodesis procedures, reduction and association procedures, and bone-ligament-bone techniques. In the absence of convincing, consistent outcomes, the authors began investigating a novel all-dorsal reconstructive technique using the Arthrex InternalBrace system. The complexity and unpredictable outcomes associated with traditional ligament tenodesis procedures led them to adopt the all-dorsal InternalBrace technique as their primary reconstructive approach. The authors have performed more than 20 procedures with this technique since 2019. In an average tourniquet time of under 60 minutes, they are able to achieve predictable carpal stabilization, pain relief, and restoration of motion. This is the preferred reconstructive approach of the senior author.


Assuntos
Ossos do Carpo , Instabilidade Articular , Osso Semilunar , Osso Escafoide , Tenodese , Humanos , Articulação do Punho/cirurgia , Ossos do Carpo/cirurgia , Tenodese/métodos , Ligamentos Articulares/cirurgia , Ligamentos Articulares/lesões , Artralgia/cirurgia , Osso Semilunar/cirurgia , Instabilidade Articular/etiologia , Instabilidade Articular/cirurgia , Osso Escafoide/cirurgia , Osso Escafoide/lesões
12.
Nat Commun ; 14(1): 3033, 2023 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-37236962

RESUMO

Materials tuned to a quantum critical point display universal scaling properties as a function of temperature T and frequency ω. A long-standing puzzle regarding cuprate superconductors has been the observed power-law dependence of optical conductivity with an exponent smaller than one, in contrast to T-linear dependence of the resistivity and ω-linear dependence of the optical scattering rate. Here, we present and analyze resistivity and optical conductivity of La2-xSrxCuO4 with x = 0.24. We demonstrate ℏω/kBT scaling of the optical data over a wide range of frequency and temperature, T-linear resistivity, and optical effective mass proportional to [Formula: see text] corroborating previous specific heat experiments. We show that a T, ω-linear scaling Ansatz for the inelastic scattering rate leads to a unified theoretical description of the experimental data, including the power-law of the optical conductivity. This theoretical framework provides new opportunities for describing the unique properties of quantum critical matter.

13.
J Hand Surg Am ; 37(10): 2007-11, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22939831

RESUMO

Schwannomas (neurilemmomas) are the most common benign tumors of peripheral nerves and originate from the myelinating cells of the nerve sheath. We present a case of congenital schwannoma of the hand.


Assuntos
Mãos/cirurgia , Neurilemoma/congênito , Neurilemoma/diagnóstico , Neoplasias do Sistema Nervoso Periférico/congênito , Neoplasias do Sistema Nervoso Periférico/diagnóstico , Mãos/inervação , Humanos , Lactente , Imageamento por Ressonância Magnética , Masculino , Neurilemoma/cirurgia , Neoplasias do Sistema Nervoso Periférico/cirurgia
14.
J Hand Surg Am ; 37(6): 1217-20, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22480507

RESUMO

Reconstruction of a distally ruptured extensor pollicis longus tendon in the rheumatoid patient generally involves a tendon transfer or intercalary graft. We present an alternative technique using the radial half of the extensor carpi radialis longus as a turn-over graft. Using the turn-over technique with a half-slip of the extensor carpi radialis longus avoids the traditional limitations of the extensor carpi radialis longus tendon in distal extensor pollicis longus tendon repairs and precludes the need for a free tendon graft.


Assuntos
Artrite Reumatoide/cirurgia , Dedos/cirurgia , Deformidades Adquiridas da Mão/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Transferência Tendinosa/métodos , Adulto , Artrite Reumatoide/complicações , Feminino , Deformidades Adquiridas da Mão/etiologia , Humanos
15.
J Hand Surg Am ; 37(12): 2580-8.e1-2, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23174073

RESUMO

PURPOSE: Few guidelines exist regarding the most effective approach to scientific oral presentations. Our purpose is to (1) develop a standardized instrument to evaluate scientific presentations based on a comprehensive review of the available literature regarding the components and organization of scientific presentations and (2) describe the optimal characteristics of scientific presentations. METHODS: At the Sixty-sixth (2011) Annual Meeting of the American Society for Surgery of the Hand, 69 presentations were evaluated by at least 2 independent observers. A rating instrument was developed a priori to examine presentation content (background, methods, results, and conclusions), presentation style (speech, structure, delivery, slide aesthetics), and overall quality. We examined correlations between reviewers' ratings of each component as well as overall perceived quality of the presentation using regression analysis. Intraclass correlation coefficients were calculated to measure the degree of variation because of reviewer disagreement and identify the aspects of presentations that contribute to overall quality. RESULTS: Reviewer agreement was high for presentation content, and less than 1% of variation was caused by reviewer disagreement for background, methods, and conclusions. With respect to presentation style, reviewers agreed most frequently regarding speech and slide appearance, and only 9% and 13%, respectively, of the variation was caused by reviewer disagreement. Disagreement was higher for delivery and presentation structure, and 21% of the variation was attributable to reviewer disagreement. Speaker delivery and slide appearance were the most important predictors of presentation quality, followed by the quality of the presentation of conclusions and background information. Presentation of methods and results were not associated with overall presentation quality. CONCLUSIONS: Distinct aspects of presentation content and style correlate with quality, which can be reliably and objectively measured. By focusing on selected concepts with visually simple slides, speakers can enhance their delivery and may potentially improve the audience's comprehension of the study findings.


Assuntos
Congressos como Assunto , Ortopedia , Comunicação , Mãos/cirurgia , Humanos , Aprendizagem , Revisão da Pesquisa por Pares , Qualidade de Vida , Sociedades Médicas
16.
Aesthetic Plast Surg ; 36(2): 387-95, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21993576

RESUMO

BACKGROUND: The usual hypertrophic scar reconstruction methods such as Z- and W-plasties can leave noticeable scars and involve excessive normal skin excision, particularly in long linear hypertrophic scars longer than 10 cm. Thus, we invented and applied the small-wave incision method for patients with linear hypertrophic scars. METHODS: A total of 40 patients with linear hypertrophic scars were included in this study. The patients were randomly assigned to the linear incision group (n = 20) or the small-wave incision group (n = 20). All scars were mildly hypertrophic, longer than 10 cm, and located in the lower abdominal/suprapubic region. They occurred after Cesarean section or gynecological or abdominal surgery. Patient age and sex, the cause of the scar, and the preoperative and postoperative sizes of the scar were recorded. Postoperative scar size and recurrence were evaluated for 18 months. Mathematical comparisons were also made to multiple linear incision, Z-plasty, planimetric Z-plasty, and W-plasty. RESULTS: Postoperative recurrence was 40 and 15% in linear and small-wave groups, respectively (P = 0.77). The main risk factor for recurrence was postoperative size (P = 0.043). Mathematical comparisons revealed that the small-wave method can achieve the same release of tension with the least normal skin excision while making the scar irregular via an accordion effect. CONCLUSION: The small-wave method can meet both the functional and the cosmetic requirements of long linear hypertrophic scar reconstruction while reducing complication risks.


Assuntos
Cicatriz Hipertrófica/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Abdome/cirurgia , Adulto , Cesárea , Cicatriz Hipertrófica/etiologia , Feminino , Procedimentos Cirúrgicos em Ginecologia , Humanos , Masculino , Recidiva , Fatores de Risco
17.
Sci Rep ; 12(1): 7202, 2022 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-35504899

RESUMO

With growing environmental awareness and considerable research investment in energy saving, the concept of energy harvesting has become a central topic in the field of materials science. The thermoelectric energy conversion, which is a classic physical phenomenon, has emerged as an indispensable thermal management technology. In addition to conventional experimental investigations of thermoelectric materials, seeking promising materials or structures using computer-based approaches such as machine learning has been considered to accelerate research in recent years. However, the tremendous experimental efforts required to evaluate materials may hinder us from reaping the benefits of the fast-developing computer technology. In this study, an electrical mapping of the thermoelectric power factor is performed in a wide temperature-carrier density regime. An ionic gating technique is applied to an oxide semiconductor WO3, systematically controlling the carrier density to induce a transition from an insulating to a metallic state. Upon electrically scanning the thermoelectric properties, it is demonstrated that the thermoelectric performance of WO3 is optimized at a highly degenerate metallic state. This approach is convenient and applicable to a variety of materials, thus prompting the development of novel functional materials with desirable thermoelectric properties.

18.
Plast Reconstr Surg ; 150(3): 659-669, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-35787599

RESUMO

BACKGROUND: Surgery is a well-known trigger of keloid and hypertrophic scarring. Sternotomy scars are subject to high skin tension, which is known to promote pathologic scarring. This suggests that sternotomies in adults are associated with high pathologic scarring rates, which aligns with the authors' anecdotal experience. However, this notion has never been examined formally. Therefore, the authors conducted a survey-based cohort study of patients who had undergone a sternotomy. METHODS: All consecutive Japanese adults (18 years of age or older) who underwent cardiovascular surgery with sternotomy in 2014 to 2017 were identified in 2019 by chart review and sent a questionnaire. Respondents formed the study cohort. The questionnaire presented randomly ordered photographs of representative mature, keloid, and hypertrophic scars and asked the patients to choose the image that best resembled their midline scar when it was particularly noticeable. The incidence of self-reported pathologic scarring (keloids and hypertrophic scars were grouped together) and the patient demographic (age and sex) and clinical characteristics (intima-media thickness of the left and right common and internal carotid arteries) that were associated with pathologic scarring were determined. RESULTS: Of the 548 patients who underwent sternotomy, 328 responded for a 60 percent response rate. The mean patient age was 67 years, and 68.0 percent were male. Of these patients, 195 (59.5 percent) reported they had a pathologic scar. Compared with patients who had a mature scar, patients who had a pathologic scar had younger mean age (65 versus 69 years; p = 0.0002) and lower intima-media thickness (0.92 versus 1.05 mm; p = 0.028). CONCLUSIONS: Sternotomy was associated with a high rate of pathologic scarring. Older age and arteriosclerosis were associated with less pathologic scarring. CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, III.


Assuntos
Arteriosclerose , Cicatriz Hipertrófica , Queloide , Ferida Cirúrgica , Adolescente , Adulto , Idoso , Arteriosclerose/complicações , Espessura Intima-Media Carotídea , Cicatriz Hipertrófica/epidemiologia , Cicatriz Hipertrófica/etiologia , Estudos de Coortes , Feminino , Humanos , Queloide/epidemiologia , Queloide/etiologia , Queloide/cirurgia , Masculino , Ferida Cirúrgica/complicações , Inquéritos e Questionários
19.
Dermatol Ther (Heidelb) ; 12(11): 2575-2587, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36205852

RESUMO

INTRODUCTION: Most lipomas are readily dissected and removed. However, some cases can pose surgical difficulties. This retrospective study sought to identify clinical and radiological risk factors that predict difficult lipoma resection and can be used in a clinically useful scoring system that predicts difficulty preoperatively. METHODS: The study cohort consisted of all consecutive patients who underwent resection of pathology-confirmed lipoma during 2016-2018 at a tertiary care referral center in Tokyo, Japan. Surgical difficulty was defined as difficulty separating some/all of the tumor from the surrounding tissue by hand and inability to extract the tumor in one piece. Descriptive, univariate, and multivariate logistic regression analyses were conducted to identify predictive factors. The predictive accuracy of the scoring system that included these factors was assessed by tenfold cross-validation analysis. Receiver-operating curve (ROC) analysis was conducted to identify the optimal cutoff score for predicting surgical difficulty. RESULTS: Of the 86 cases, 36% involved surgical difficulty. Multivariate analysis showed that subfascial intramuscular location (odds ratio 42.7, 95% confidence interval 3.0-608.0), broad touching of underlying structures (46.5, 3.7-586.0), in-flowing blood vessels (9.3, 1.1-78.5), and unclear boundaries (109.0, 1.1-1110.0) significantly predicted surgical difficulty. These factors were used to construct a 0-4 point scoring system (with one point per variable). On cross-validation, the accuracy of the scoring system was 82.4% (Cohen's kappa of 0.57). ROC analysis showed that scores ≥ 2 predicted surgical difficulty with sensitivity and specificity of 55% and 98%, respectively. CONCLUSIONS: Our scoring system accurately predicted lipoma resection difficulty and may help operators prepare, thereby facilitating surgery.

20.
Plast Reconstr Surg ; 150(5): 1049-1057, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-35994349

RESUMO

BACKGROUND: Soft-tissue defects in the hand and digits can be effectively covered by using the free superficial palmar branch of the radial artery (SPBRA) flap, which is harvested from the radial volar wrist. Because previous anatomical studies on this flap are limited, multidetector-row computed tomographic angiography of the upper limbs was conducted to characterize the three-dimensional anatomical structure of the SPBRA and its perforators in living patients. METHODS: This retrospective anatomical study was conducted from 2014 to 2019. All data from Digital Imaging and Communications in Medicine were analyzed by using their viewer. SPBRA diameter and the location where it bifurcated from the radial artery were recorded, as were the number, location, branching patterns, and diameters of its perforators and their lengths. RESULTS: In total, 30 patients met all eligibility criteria. All had the SPBRA. The vessel bifurcated from the radial artery on average 13.2 mm proximally from the radial styloid process. The 30 patients had 40 SPBRA perforators in total. Their average SPBRA-to-dermis length was 6.43 mm. All patients had at least one direct cutaneous perforator. Nine and one also had one musculocutaneous perforator and another direct perforator, respectively. All direct cutaneous perforators were located inside a 16.4-mm-diameter circle with an origin on the scaphoid tubercle. The mean diameters of the SPBRA and its perforators were 1.12 and 0.62 mm, respectively. CONCLUSIONS: All patients had at least one reliable SPBRA perforator in the radial volar wrist. The authors' results suggest that plastic surgeons can easily and safely plan the SPBRA flap design, potentially without preoperative perforator mapping.


Assuntos
Retalho Perfurante , Procedimentos de Cirurgia Plástica , Humanos , Retalho Perfurante/irrigação sanguínea , Artéria Radial/diagnóstico por imagem , Artéria Radial/cirurgia , Estudos Retrospectivos , Procedimentos de Cirurgia Plástica/métodos , Tomografia Computadorizada Multidetectores
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