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1.
ACS Omega ; 7(18): 15760-15768, 2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-35571781

RESUMO

Quantum spin Hall (QSH) insulators with large band gaps and dissipationless edge states are of both technological and scientific interest. Although numerous two-dimensional (2D) systems have been predicted to host the QSH phase, very few of them harbor large band gaps and retain their nontrivial band topology when they are deposited on substrates. Here, based on a first-principles analysis with hybrid functional calculations, we investigated the electronic and topological properties of inversion-asymmetric monolayer copper sulfide (Cu2S). Interestingly, we found that monolayer Cu2S possesses an intrinsic QSH phase, Rashba spin splitting, and a large band gap of 220 meV that is suitable for room-temperature applications. Most importantly, we constructed heterostructures of a Cu2S film on PtTe2, h-BN, and Cu(111) substrates and found that the topological properties remain preserved upon an interface with these substrates. Our findings suggest Cu2S as a possible platform to realize inversion-asymmetric QSH insulators with potential applications in low-dissipation electronic devices.

2.
Sci Rep ; 12(1): 4582, 2022 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-35301355

RESUMO

Topological Dirac materials are attracting a lot of attention because they offer exotic physical phenomena. An exhaustive search coupled with first-principles calculations was implemented to investigate 10 Zintl compounds with a chemical formula of CaM2X2 (M = Zn or Cd, X = N, P, As, Sb, or Bi) under three crystal structures: CaAl2Si2-, ThCr2Si2-, and BaCu2S2-type crystal phases. All of the materials were found to energetically prefer the CaAl2Si2-type structure based on total ground state energy calculations. Symmetry-based indicators are used to evaluate their topological properties. Interestingly, we found that CaM2Bi2 (M = Zn or Cd) are topological crystalline insulators. Further calculations under the hybrid functional approach and analysis using k · p model reveal that they exhibit topological Dirac semimetal (TDSM) states, where the four-fold degenerate Dirac points are located along the high symmetry line in-between Г to A points. These findings are verified through Green's function surface state calculations under HSE06. Finally, phonon spectra calculations revealed that CaCd2Bi2 is thermodynamically stable. The Zintl phase of AM2X2 compounds have not been identified in any topological material databases, thus can be a new playground in the search for new topological materials.

3.
J Phys Condens Matter ; 34(6)2021 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-34727535

RESUMO

Cadmium oxide (CdO)-ZnO alloys (CdxZn1-xO) exhibit a transformation from the wurtzite to the rocksalt (RS) phase at a CdO composition of ∼70% with a drastic change in the band gap and electrical properties. RS-CdxZn1-xO alloys (x> 0.7) are particularly interesting for transparent conductor applications due to their wide band gap and high electron mobility. In this work, we synthesized RS-CdxZn1-xO alloys doped with different concentrations of In dopants and evaluated their electrical and optical properties. Experimental results are analyzed in terms of the amphoteric native defect model and compared directly to defect formation energies obtained by hybrid density functional theory (DFT) calculations. A saturation in electron concentration of ∼7 × 1020 cm-3accompanied by a rapid drop in electron mobility is observed for the RS-CdxZn1-xO films with 0.7 ⩽x< 1 when the In dopant concentration [In] is larger than 3%. Hybrid DFT calculations confirm that the formation energy of metal vacancy acceptor defects is significantly lower in RS-CdxZn1-xO than in CdO, and hence limits the free carrier concentration. Mobility calculations reveal that due to the strong compensation by native defects, RS-CdxZn1-xO alloys exhibit a compensation ratio of >0.7 for films withx< 0.8. As a consequence of the compensation by native defects, in heavily doped RS-CdxZn1-xO carrier-induced band filling effect is limited. Furthermore, the much lower mobility of the RS-CdxZn1-xO alloys also results in a higher resistivity and reduced transmittance in the near infra-red region (λ > 1100 nm), making the material not suitable as transparent conductors for full spectrum photovoltaics.

4.
P R Health Sci J ; 40(1): 56-58, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33876921

RESUMO

Small-bowel bleeding is a relatively uncommon event of gastrointestinal bleeding. Some causes of small-bowel bleeding, such as vascular lesions, are still challenging to confirm, despite the use of various diagnostic modalities (e.g., capsule endoscopy, deep enteroscopy, and radiographic imaging). Vascular lesion-induced bleeding tends to be insidious and intermittent, but sometimes it can be massive and fatal, so that the timing of an endoscopy is critical. We describe herein the case of an elderly female patient with Dieulafoy's lesion-induced small-bowel bleeding presenting with recurrent melena. In this article, we describe how the cause of her bleeding was found and how the bleeding was stopped endoscopically. Finally, we discuss the characteristics of a small-bowel Dieulafoy's lesion and its endoscopic treatment.


Assuntos
Endoscopia por Cápsula , Hemorragia Gastrointestinal/etiologia , Mucosa Intestinal/irrigação sanguínea , Idoso , Artérias/anormalidades , Endoscopia Gastrointestinal , Feminino , Hemorragia Gastrointestinal/cirurgia , Hemostase Endoscópica , Humanos , Mucosa Intestinal/cirurgia , Melena/etiologia , Recidiva
5.
Nanoscale Adv ; 3(23): 6608-6616, 2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-36132660

RESUMO

Recent studies have demonstrated the feasibility of synthesizing two-dimensional (2D) Janus materials which possess intrinsic structural asymmetry. Hence, we performed a systematic first-principles study of 2D Janus transition metal dichalcogenide (TMD) monolayers based on PtXY (X,Y = S, Se, or Te). Our calculated formation energies show that these monolayer Janus structures retain the 1T phase. Furthermore, phonon spectral calculations confirm that these Janus TMD monolayers are thermodynamically stable. We found that PtSSe, PtSTe, and PtSeTe exhibit an insulating phase with indirect band gaps of 2.108, 1.335, and 1.221 eV, respectively, from hybrid functional calculations. Due to the breaking of centrosymmetry in the crystal structure, the spin-orbit coupling (SOC)-induced anisotropic Rashba splitting is observed around the M point. The calculated Rashba strengths from M to Γ (α M-Γ R) are 1.654, 1.103, and 0.435 eV Å-1, while the calculated values from M to K (α M-K R) are 1.333, 1.244, and 0.746 eV Å-1, respectively, for PtSSe, PtSTe, and PtSeTe. Interestingly, the spin textures reveal that the spin-splitting is mainly attributed to the Rashba effect. However, a Dresselhaus-like contribution also plays a secondary role. Finally, we found that the band gaps and the strength of the Rashba effect can be further tuned through biaxial strain. Our findings indeed show that Pt-based Janus TMDs demonstrate the potential for spintronics applications.

6.
Nat Commun ; 11(1): 4415, 2020 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-32887890

RESUMO

Quantum states induced by single-atomic impurities are at the frontier of physics and material science. While such states have been reported in high-temperature superconductors and dilute magnetic semiconductors, they are unexplored in topological magnets which can feature spin-orbit tunability. Here we use spin-polarized scanning tunneling microscopy/spectroscopy (STM/S) to study the engineered quantum impurity in a topological magnet Co3Sn2S2. We find that each substituted In impurity introduces a striking localized bound state. Our systematic magnetization-polarized probe reveals that this bound state is spin-down polarized, in lock with a negative orbital magnetization. Moreover, the magnetic bound states of neighboring impurities interact to form quantized orbitals, exhibiting an intriguing spin-orbit splitting, analogous to the splitting of the topological fermion line. Our work collectively demonstrates the strong spin-orbit effect of the single-atomic impurity at the quantum level, suggesting that a nonmagnetic impurity can introduce spin-orbit coupled magnetic resonance in topological magnets.

7.
Chin J Dent Res ; 23(1): 71-76, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32232232

RESUMO

Endoscopic techniques have been applied to oral and maxillofacial surgeries. Previous studies have proved their practicability in the treatment of osteomyelitis of the mandible and displaced residual roots in the maxillary sinus. In this report, two patients with dentigerous cysts in the maxillary sinus underwent endoscope-assisted curettage. Both patients were successfully cured without recurrent lesions or any complications. The follow-up found that the bone cavities had shrunk. An endoscope-assisted Caldwell-Luc operation provided clear visibility of the surgical field and preserved the mucosa of the maxillary sinus.


Assuntos
Cisto Dentígero , Seio Maxilar , Endoscopia , Humanos
8.
Nanoscale Res Lett ; 15(1): 56, 2020 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-32140792

RESUMO

We report a new graphene allotrope named HOT graphene containing carbon hexagons, octagons, and tetragons. A corresponding series of nanotubes are also constructed by rolling up the HOT graphene sheet. Ab initio calculations are performed on geometric and electronic structures of the HOT graphene and the HOT graphene nanotubes. Dirac cone and high Fermi velocity are achieved in a non-hexagonal structure of HOT graphene, implying that the honeycomb structure is not an indispensable condition for Dirac fermions to exist. HOT graphene nanotubes show distinctive electronic structures depending on their topology. The (0,1) n (n ≥ 3) HOT graphene nanotubes reveal the characteristics of semimetals, while the other set of nanotubes (1,0) n shows continuously adjustable band gaps (0~ 0.51 eV) with tube size. A competition between the curvature effect and the zone-folding approximation determines the band gaps of the (1,0) n nanotubes. Novel conversion between semimetallicity and semiconductivity arises in ultra-small tubes (radius < 4 Å, i.e., n < 3).

9.
Phys Rev Lett ; 123(21): 217004, 2019 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-31809171

RESUMO

The interplay between unconventional Cooper pairing and quantum states associated with atomic scale defects is a frontier of research with many open questions. So far, only a few of the high-temperature superconductors allow this intricate physics to be studied in a widely tunable way. We use scanning tunneling microscopy to image the electronic impact of Co atoms on the ground state of the LiFe_{1-x}Co_{x}As system. We observe that impurities progressively suppress the global superconducting gap and introduce low energy states near the gap edge, with the superconductivity remaining in the strong-coupling limit. Unexpectedly, the fully opened gap evolves into a nodal state before the Cooper pair coherence is fully destroyed. Our systematic theoretical analysis shows that these new observations can be quantitatively understood by the nonmagnetic Born-limit scattering effect in an s±-wave superconductor, unveiling the driving force of the superconductor to metal quantum phase transition.

10.
ACS Appl Mater Interfaces ; 11(36): 33012-33021, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31414595

RESUMO

Spinel oxides (AB2O4) with unique crystal structures have been widely explored as promising alternative catalysts for efficient oxygen evolution reactions; however, developing novel methods to fabricate robust, cost-effective, and high-performance spinel oxide based electrocatalysts is still a great challenge. Here, utilizing a complementary experimental and theoretical approach, pentavalent vanadium doping in the spinel oxides (i.e., Co3O4 and NiFe2O4) has been thoroughly investigated to engineer their surface structures for the enhanced electrocatalytic oxygen evolution reaction. Specifically, when the optimal concentration of vanadium (ca. 7.7 at. %) is incorporated into Co3O4, the required overpotential to reach a certain jGEOM and jECSA decreases dramatically for oxygen evolution reactions in alkaline media. Even after 30 h of chronopotentiometry, the required potential for V-doped Co3O4 just increases by 16.3 mV, being much lower than that of the undoped one. It is observed that the pentavalent vanadium doping introduces lattice distortions and defects on the surface, which in turn exposes more active sites for reactions. DFT calculations further reveal the rate-determining step changing from the step of *-O to *-OOH to the step of *-OH to *-O, while the corresponding energy barriers decrease from 1.73 to 1.57 eV accordingly after high-valent V doping. Moreover, the oxygen intermediate probing method using methanol as a probing reagent also demonstrates a stronger OH* adsorption on the surface after V doping. When vanadium doping is performed in the inverse spinel matrix of NiFe2O4, impressive performance enhancement in the oxygen evolution reaction is as well witnessed. All these results clearly illustrate that the V doping process can not only efficiently improve the electrochemical properties of spinel transition metal oxides but also provide new insights into the design of high-performance water oxidation electrocatalysts.

11.
Sci Adv ; 5(7): eaav7717, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31360763

RESUMO

The zigzag-edged triangular graphene molecules (ZTGMs) have been predicted to host ferromagnetically coupled edge states with the net spin scaling with the molecular size, which affords large spin tunability crucial for next-generation molecular spintronics. However, the scalable synthesis of large ZTGMs and the direct observation of their edge states have been long-standing challenges because of the molecules' high chemical instability. Here, we report the bottom-up synthesis of π-extended [5]triangulene with atomic precision via surface-assisted cyclodehydrogenation of a rationally designed molecular precursor on metallic surfaces. Atomic force microscopy measurements unambiguously resolve its ZTGM-like skeleton consisting of 15 fused benzene rings, while scanning tunneling spectroscopy measurements reveal edge-localized electronic states. Bolstered by density functional theory calculations, our results show that [5]triangulenes synthesized on Au(111) retain the open-shell π-conjugated character with magnetic ground states.

12.
Head Neck ; 41(5): 1450-1456, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30636085

RESUMO

BACKGROUND: The aim of this study was to investigate the value of a smartphone-compatible thermal imaging camera in the mapping of the peroneal artery perforators. METHODS: Twelve consecutive patients scheduled for fibular flap reconstruction were enrolled. The lower limbs were first studied using smartphone-based dynamic infrared thermography (DIRT). During the rewarming, the hotspots were marked, small rubber markers were taped to the registered sites, and then the patients were sent for a CT scan. The diagnostic performance of smartphone-based DIRT was evaluated by comparing the DIRT findings with CT angiography and intraoperative findings. RESULTS: DIRT detected 42 of the 57 dominant perforators in 24 limbs and resulted in a sensitivity of 73.7% and a positive predictive value of 65.6%. CONCLUSIONS: The sensitivity and positive predictive value of the smartphone-based DIRT are low. Currently, it should be used as an adjunctive tool together with the established imaging techniques.


Assuntos
Angiografia por Tomografia Computadorizada/métodos , Fíbula/cirurgia , Retalho Perfurante/irrigação sanguínea , Smartphone/estatística & dados numéricos , Termografia/métodos , Adulto , Idoso , Estudos de Coortes , Feminino , Fíbula/diagnóstico por imagem , Seguimentos , Sobrevivência de Enxerto , Humanos , Masculino , Pessoa de Meia-Idade , Monitorização Intraoperatória/métodos , Retalho Perfurante/transplante , Cuidados Pré-Operatórios/métodos , Estudos Retrospectivos , Medição de Risco , Estatísticas não Paramétricas , Resultado do Tratamento
13.
Sci Rep ; 9(1): 756, 2019 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-30679630

RESUMO

Synchrotron radiation core-level photoemission spectroscopy, scanning tunneling microscopy (STM), and first-principles calculations have been utilized to explore the growth processes and the atomic structure of the resulting films during the two-step molecular beam epitaxy (MBE) of In and Bi on the Si(111) surface. Deposition of 1.0-ML Bi on the In/Si(111)-(4 × 1) surface at room temperature results in Bi-terminated BiIn-(4 × 3) structures, which are stable up to ~300 °C annealing. By contrast, deposition of In on the ß-Bi/Si(111)-(√3 × âˆš3) surface at room temperature results in three dimensional (3D) In islands. In both cases, annealing at 460 °C results in the same In-terminated In0.75Bi/Si(111)-(2 × 2) surface. Our DFT calculations confirm that the surface energy of In-terminated In0.75Bi/Si(111)-(2 × 2) system is lower than that of Bi-terminated Bi0.75In/Si(111)-(2 × 2). These findings provide means for the control of the polarity of the MBE In-Bi atomically thick films.

14.
Artigo em Inglês | MEDLINE | ID: mdl-29627200

RESUMO

OBJECTIVES: Osteoradionecrosis of the mandible is a late radiation-induced complication, which is a major concern in survivors of head and neck cancer. STUDY DESIGN: In this study, we present a case of a patient with nasopharyngeal carcinoma who developed extensive bilateral osteoradionecrosis of the ascending ramus of the mandible. After preoperative virtual surgical planning, the obtained data were used to fabricate patient-specific cutting templates. The bilateral mandibular defects were reconstructed using 2 separate flaps prepared from a single fibula. RESULTS: Both defects were successfully reconstructed, and satisfactory aesthetic and functional results were achieved. CONCLUSIONS: Bilateral mandibular osteoradionecrosis can be managed with virtual surgical planning, and the defects can be reconstructed using 2 separate flaps prepared from a single fibula.


Assuntos
Fíbula/transplante , Retalhos de Tecido Biológico , Reconstrução Mandibular/métodos , Osteorradionecrose/cirurgia , Cirurgia Assistida por Computador , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Nasofaríngeas/radioterapia , Osteorradionecrose/diagnóstico por imagem , Radiografia Panorâmica , Tomografia Computadorizada por Raios X
15.
Nanoscale Res Lett ; 13(1): 43, 2018 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-29417237

RESUMO

The abounding possibilities of discovering novel materials has driven enhanced research effort in the field of materials physics. Only recently, the quantum anomalous hall effect (QAHE) was realized in magnetic topological insulators (TIs) albeit existing at extremely low temperatures. Here, we predict that MPn (M =Ti, Zr, and Hf; Pn =Sb and Bi) honeycombs are capable of possessing QAH insulating phases based on first-principles electronic structure calculations. We found that HfBi, HfSb, TiBi, and TiSb honeycomb systems possess QAHE with the largest band gap of 15 meV under the effect of tensile strain. In low-buckled HfBi honeycomb, we demonstrated the change of Chern number with increasing lattice constant. The band crossings occurred at low symmetry points. We also found that by varying the buckling distance we can induce a phase transition such that the band crossing between two Hf d-orbitals occurs along high-symmetry point K2. Moreover, edge states are demonstrated in buckled HfBi zigzag nanoribbons. This study contributes additional novel materials to the current pool of predicted QAH insulators which have promising applications in spintronics.

16.
Head Neck ; 40(2): 349-354, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28963817

RESUMO

BACKGROUND: This study compared the outcomes of an extensive segmental pectoralis major myocutaneous flap (esPMMF) and a conventional pectoralis major myocutaneous flap (PMMF). METHODS: The study enrolled 91 patients with primary oral and oropharyngeal squamous cell carcinoma (SCC) who underwent radical resection followed by reconstruction of the defect using either an esPMMF via the anterior axillary line or a PMMF. The pedicle lengths of the esPMMF and PMMF were 22-28 and 18-22 cm, respectively. The esPMMF and PMMF had skin paddle dimensions of 5 × 8 to 7 × 14 cm and 6 × 7 to 8 × 17 cm, respectively. RESULTS: The esPMMF pedicle was longer than that of the PMMF. The range of shoulder abduction was significantly greater in the esPMMF group and the donor-site aesthetic results were better. CONCLUSION: The esPMMF has a longer pedicle flap, enables a greater range of shoulder abduction, and has a better aesthetic result than the conventional technique.


Assuntos
Carcinoma de Células Escamosas/cirurgia , Neoplasias Bucais/cirurgia , Retalho Miocutâneo , Neoplasias Orofaríngeas/cirurgia , Músculos Peitorais/transplante , /métodos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Amplitude de Movimento Articular , Ombro/patologia , Ombro/fisiologia , Resultado do Tratamento
17.
Am J Transl Res ; 9(7): 3474-3486, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28804564

RESUMO

H19 is involved in tumor metastasis and associated with tumor progression. Enhancer of zest homolog 2 (EZH2) is overexpressed in multiple cancer types and correlates with tumor proliferation, epithelial-mesenchymal transition, and poor prognosis. However, the interaction between H19 and EZH2 to promote tongue squamous cell carcinoma (TSCC) progression remains largely uncharacterized. Insitu hybridization and quantitative reverse-transcription PCR (qRT-PCR) were performed to measure H19 expression in primary TSCC and adjacent normal tissues and cell lines. EZH2 expression was determined by immunohistochemistry in matched primary TSCC and adjacent normal tissues. The correlation between H19 and EZH2 expression and clinicopathological characteristics were analyzed. The roles of H19 in cell proliferation, apoptosis, and invasion were analyzed using a H19-targeted lentivirus. Western blot and qRT-PCR were carried out to detect downstream signal pathway changes. Expression levels of downstream signaling proteins in primary TSCC tissues and adjacent normal tissues were analyzed by immunohistochemistry. H19 and EZH2 were upregulated in TSCC tissues compared to matched normal tissues, and significantly correlated with WHO grade, lymph node metastasis, and poor prognosis. H19 silencing attenuated cell proliferation, apoptosis, and invasion in vitro. H19 knockdown inhibited the activation of ß-catenin/GSK-3ß/cyclin D1/c-myc, upregulated E-cadherin and zonula occludens-1 (ZO-1), and inhibited N-cadherin, vimentin, Snail1, Twist1, and ZEB1. Silencing H19 expression also inhibited tumor progression and lung metastasis in an animal model. Our findings indicate that H19 promotes TSCC progression through association with EZH2, and affects downstream ß-Catenin/GSK3ß/EMT signaling, suggesting that H19 inhibition might be a potential target for the treatment of TSCC.

18.
ACS Nano ; 11(9): 8768-8776, 2017 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-28753274

RESUMO

Integration of strain engineering of two-dimensional (2D) materials in order to enhance device performance is still a challenge. Here, we successfully demonstrated the thermally strained band gap engineering of transition-metal dichalcogenide bilayers by different thermal expansion coefficients between 2D materials and patterned sapphire structures, where MoS2 bilayers were chosen as the demonstrated materials. In particular, a blue shift in the band gap of the MoS2 bilayers can be tunable, displaying an extraordinary capability to drive electrons toward the electrode under the smaller driven bias, and the results were confirmed by simulation. A model to explain the thermal strain in the MoS2 bilayers during the synthesis was proposed, which enables us to precisely predict the band gap-shifted behaviors on patterned sapphire structures with different angles. Furthermore, photodetectors with enhancement of 286% and 897% based on the strained MoS2 on cone- and pyramid-patterned sapphire substrates were demonstrated, respectively.

19.
J Craniofac Surg ; 28(4): 976-979, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28169907

RESUMO

BACKGROUND: Resection of the parapharyngeal space is often challenging. This study aims to evaluate the outcome of the endoscopy-assisted transoral approach for resection of the parapharyngeal space tumors compared with the endoscopy-assisted transcervical approach. METHODS: Twenty-three consecutive patients (15 males, 8 females) who underwent resection of large parapharyngeal space tumors via endoscopy-assisted transoral (ETO) approach or endoscopy-assisted transcervical minimal incision plus osteotomy of the vertical ramus outside the mandibular foramen (ETC + MO) approach were analyzed retrospectively. RESULTS: The tumors in ETO group are benign; there are 2 patients with adenoid cystic carcinoma and 1 patient with recurrent pleomorphic adenoma in ETC + MO group. All of the tumors were removed completely and without rupture. No major complications developed in any patient. Temporary facial paresis occurred in 1 patient in the ETC + MO group, which resolved spontaneously within 8 weeks. The cosmetic effects of all patients in ETO groups and 10 patients in ETC + MO groups were excellent. Patients were followed up for 7 to 26 months, no recurrence was encountered. CONCLUSION: ETO and ETC + MO approach in resection of large parapharyngeal space tumors are feasible and safe technique that achieve excellent aesthetic and functional results. Endoscopy-assisted transoral approach can shorten hospitalized time and avoid the risk of marginal mandibular nerve injury and ETC + MO approach may be used in malignant or recurrent parapharyngeal space tumors.


Assuntos
Adenoma Pleomorfo/cirurgia , Carcinoma Adenoide Cístico/cirurgia , Endoscopia/métodos , Osteotomia Mandibular/métodos , Neoplasias Faríngeas/cirurgia , Adolescente , Adulto , Feminino , Humanos , Masculino , Mandíbula/cirurgia , Pessoa de Meia-Idade , Cirurgia Endoscópica por Orifício Natural/métodos , Osteotomia/métodos , Estudos Retrospectivos , Adulto Jovem
20.
J Oral Maxillofac Surg ; 75(3): 622-631, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27717818

RESUMO

PURPOSE: Head and neck tumors that involve the craniomaxillofacial region are classified as stage IVb disease and are clinically challenging. In this study, the outcomes of craniofacial resection and craniofacial reconstruction in patients with recurrent malignant tumors involving the craniomaxillofacial region were evaluated. PATIENTS AND METHODS: This retrospective observational study was conducted from January 2008 to August 2015. Data collected for each patient included age, gender, tumor site, initial treatment, craniofacial resection, reconstruction flaps and complications after craniofacial resection, adjuvant treatment, and reported outcomes of craniofacial resection and craniofacial reconstruction. The χ2 test in SPSS was used to analyze the data. RESULTS: Twenty-four patients with recurrent malignant tumors involving the craniomaxillofacial region were identified who had undergone craniofacial resection at the Center of Craniomaxillofacial Surgery of Sun Yat-sen University (Guangzhou, Guangdong, China). The study population was comprised of 24 patients (15 men and 9 women; age range, 21 to 73 yr) with recurrent tumors (58.3% with squamous cell carcinoma [SCC], 41.7% with sarcoma [SA]) involving the craniomaxillofacial region who underwent craniofacial resection. Craniofacial resection consisted of orbital exenteration and maxillotomy; anterior skull base surgery, facial resection, and mandibulotomy; or ipsilateral radical neck dissection. The resultant craniomaxillofacial defects were reconstructed using extended vertical lower trapezius island myocutaneous flaps (TIMFs), temporalis myofascial flaps, or submental flaps. All patients with recurrent malignant tumor involving the craniomaxillofacial region underwent gross total resection of the tumor; 22 patients underwent craniofacial reconstruction. There were no major surgical complications. Minor flap failure and wound dehiscence in the donor site occurred in 4 patients. The follow-up period ranged from 8 to 36 months. Seven patients in the SCC group and 7 in the SA group were alive with no evidence of disease (AND), 3 in the SCC group and 2 in the SA group were alive with disease (AWD), and 4 in the SCC and 1 in the SA group died of the disease (DOD) after local recurrence or distant metastases at 8 to 18 months. There were no statistical differences among the AND, AWD, and DOD groups. CONCLUSIONS: Craniofacial resection remains an effective salvage treatment for patients with recurrent SCC and SA involving the craniomaxillofacial region. The extended vertical lower TIMF is a large, simple, and reliable flap for reconstructing major defects after a craniofacial resection.


Assuntos
Neoplasias de Cabeça e Pescoço/cirurgia , Recidiva Local de Neoplasia/cirurgia , /métodos , Adulto , Idoso , Diagnóstico por Imagem , Feminino , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Estudos Retrospectivos , Retalhos Cirúrgicos , Resultado do Tratamento
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