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Coaxial type piezoelectric energy generator (C-PEG) nanofiber was fabricated by a self-designed continuous electrospinning deposition system. Piezoelectric PVDF-TrFE nanofiber as an electroactive material was electrospun at a discharge voltage of 9-12 kV onto a simultaneously rotating and transverse moving Cu metal wire at an angular velocity of ω g = 60-120 RPM. The piezoelectric coefficient d33 of the PVDF-TrFE nanofiber was approximately -20 pm V-1. The generated output voltage (V G) increased according to the relationship exp(-α P) (α = 0.41- 0.57) as the pressure (P) increased from 30 to 500 kpa. The V G values for ten and twenty pieces of C-PEG were V G = 3.9 V and 9.5 V at P = 100 kpa, respectively, relatively high output voltages compared to previously reported values. The high V G for the C-PEG stems from the fact that it can generate a fairly high V G due to the increased number of voltage collection points compared to a conventional two-dimensional (2-dim) capacitor type of piezoelectric film or fiber device. C-PEG yarn was also fabricated via the dip-coating of a PDMS polymer solution, followed by winding with Ag-coated nylon fiber as an outer electrode. The current and power density of ten pieces of C-PEG yarn were correspondingly 22 nA cm-2 and 8.6 µW cm-3 at V G = 1.97 V, higher than previously reported values of 5.54 and 6 µW cm-3. The C-PEG yarn, which can generate high voltage compared to the conventional film/nanofiber mat type, is expected to be very useful as a wearable energy generator system.
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ZnO nanoparticles (NPs) of 4-5 nm, widely adopted as an electron transport layer (ETL) in quantum dot light emitting diodes (QD-LEDs), were synthesized using the solution-precipitation process. It is notable that synthesized ZnO NPs are highly degenerate intrinsic semiconductors and their donor concentration can be increased up to N D = 6.9 × 1021 cm-3 by annealing at 140 °C in air. An optical bandgap increase of as large as 0.16-0.33 eV by degeneracy is explained well by the Burstein-Moss shift. In order to investigate the influence of intrinsic defects of ZnO NP ETLs on the performance of QD-LED devices without a combined annealing temperature between ZnO NP ETLs and the emissive QD layer, pre-annealed ZnO NPs at 60 °C, 90 °C, 140 °C, and 180 °C were spin-coated on the annealed QD layer without further post-annealing. As the annealing temperature increases from 60 °C to 180 °C, the defect density related to oxygen vacancy (V O) in ZnO NPs is reduced from 34.4% to 17.8%, whereas the defect density of interstitial Zn (Zni) is increased. Increased Zni reduces the width (W) of the depletion region from 0.21 to 0.12 nm and lowers the Schottky barrier (ФB) between ZnO NPs and the Al electrode from 1.19 to 0.98 eV. We reveal for the first time that carrier conduction between ZnO NP ETLs and the Al electrode is largely affected by the concentration of Zni above the conduction band minimum, and effectively described by space charge limited current and trap charge limited current models.
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We investigate the growth procedures for achieving taper-free and kinked germanium nanowires epitaxially grown on silicon substrates by chemical vapor deposition. Singly and multiply kinked germanium nanowires consisting of <111> segments were formed by employing a reactant gas purging process. Unlike non-epitaxial kinked nanowires, a two-temperature process is necessary to maintain the taper-free nature of segments in our kinked germanium nanowires on silicon. As an application, nanobridges formed between (111) side walls of V-grooved (100) silicon substrates have been demonstrated.
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TiNx films were successfully deposited by DC reactive magnetron sputtering superimposed EMF system without substrate heating. In case of DCMS 400 W+ EMF 25 W, electrical property, reflectance and crystallinity of the TiN films were clearly improved by the enhancement of nitrification. The lowest sheet resistance of 2.9 Ω/⟂ (resistivity 5.8 x 10(-5) Ωcm) was observed for the film deposited at F(N)2: 16%. Mixture phases of the (111) plane and (200) plane showed lower resistivity than only (200) single phase. Therefore it is confirmed that introduction of EMF system is promising technology to deposit TiN film.
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INTRODUCTION: The aim of this study was to evaluate the correlation between carotid siphon (CS) calcification and lacunar infarction caused by small-vessel disease. METHODS: This retrospective study included 445 patients (M/F = 256:189) older than 40 years (mean age 60.0 ± 12.3 years, range 41-98 years) without large intracranial lesions who had undergone both brain CT and MRI within an interval of 6 months. The patients were classified into three groups according to the number of lacunar infarctions: group I-zero infarctions (n = 328), group II-one to three infarctions (n = 94), and group III-four or more infarctions (n = 23). The severity of CS calcification was evaluated on CT and scored on a five-point scale (0-none, 1-stippled, 2-thin continuous or thick discontinuous, 3-thick continuous, 4-double tracts), and the calcification scores on both sides were summed. An ANOVA test was used to compare calcification scores among the three groups, and a logistic regression test was used to evaluate the influence of CS calcification and known cerebrovascular risk factors on the occurrence of lacunar infarction. RESULTS: On the ANOVA test, total calcification scores were significantly different among the three groups (group I = 1.28 ± 1.99, group II = 3.31 ± 2.39, group III = 4.36 ± 2.08; P < 0.05). Higher rates of lacunar infarction were associated with higher CS calcification scores. On the logistic regression test, CS calcification, age, and hypertension were significant risk factors for lacunar infarction (P < 0.05). CONCLUSION: CS calcification was correlated with the occurrence of lacunar infarction. The degree of CS calcification may be used to predict the possibility of a future lacunar infarction.
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Calcinose/patologia , Artéria Carótida Interna/patologia , Estenose das Carótidas/patologia , Imageamento por Ressonância Magnética , Acidente Vascular Cerebral Lacunar/patologia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Calcinose/diagnóstico por imagem , Artéria Carótida Interna/diagnóstico por imagem , Estenose das Carótidas/diagnóstico por imagem , Feminino , Humanos , Hipertensão/complicações , Hipertensão/patologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Acidente Vascular Cerebral Lacunar/diagnóstico por imagem , Tomografia Computadorizada por Raios XRESUMO
OBJECTIVES: The aim of study was to assess the usefulness of 3D ultrasonography (3DUS) in the diagnosis of carpal tunnel syndrome. METHODS: Fifty patients with carpal tunnel syndrome confirmed by electromyography and 37 healthy control participants underwent 3DUS of the wrists. The mean times per participant for the 3DUS examination and review of the 3D volume set were recorded. The cross-sectional area at the proximal carpal tunnel and the maximum swelling point were measured. Data from patients and controls were compared for determination of statistical significance. The accuracy of the 3DUS diagnostic criteria for carpal tunnel syndrome was evaluated using receiver operating characteristic analysis, and changes in the median nerve shape, including the maximum swelling point, were assessed by review of the 3D volume data. RESULTS: The mean times for examination of a participant and review in each wrist were 56 seconds and 5.7 minutes, respectively. Significant differences were observed in the mean cross-sectional areas of the median nerve between patients and controls. The mean cross-sectional areas ± SD were 16.7 ± 6.7 mm(2) in patients and 8.3 ± 1.9 mm(2) in controls. Using the receiver operating characteristic curve, a cutoff value of greater than 10.5 mm(2) provided diagnostic sensitivity of 84% and specificity of 86%. In 42 of 73 wrists with carpal tunnel syndrome, the median nerve showed fusiform morphologic abnormalities and maximum swelling points. CONCLUSIONS: Our results show that 3DUS could markedly decrease scanning time, and measurement of the median nerve cross-sectional area combined with morphologic analysis using 3DUS is a promising supplementary method for the diagnosis of carpal tunnel syndrome.
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Síndrome do Túnel Carpal/diagnóstico por imagem , Imageamento Tridimensional/métodos , Adulto , Idoso , Feminino , Humanos , Masculino , Nervo Mediano/diagnóstico por imagem , Pessoa de Meia-Idade , Curva ROC , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Ultrassonografia , Articulação do Punho/diagnóstico por imagemRESUMO
Pulse wave velocity (PWV) and augmentation index (AI) are both indirect indicators of arterial stiffness, which is an independent predictor of morbidity and mortality in cardiovascular diseases. The aim of this study was to assess the association between carotid AI (CAI), carotid-femoral PWV (CFPWV), and Framingham risk score (FRS), and to evaluate the factors determining CAI and CFPWV. Carotid AI and CFPWV were measured by applanation tonometry in 177 consecutive subjects without evidence of significant cardiovascular disease. Correlations between CAI and FRS and CFPWV and FRS were analyzed and major determinants of CAI and CFPWV were assessed. The mean age was 60.5 +/- 11.9 years and 112 (63%) of study patients were men. There was a significant association between CFPWV and FRS (r = 0.417, P < 0.001) and a weaker but also significant relation between CAI and FRS (r = 0.267, P < 0.001). CFPWV was significantly related to FRS in both men and women (P < 0.001 in both sexes), whereas the relation between CAI and FRS was significant only in women (P < 0.001). Our results suggest that CFPWV may be associated with CVD risk irrespective of sex, whereas CAI may be associated with CVD risk in women only.
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Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/fisiopatologia , Artérias Carótidas/fisiopatologia , Artéria Femoral/fisiopatologia , Fluxo Pulsátil , Distribuição por Idade , Fatores Etários , Idoso , Pressão Sanguínea , Estudos Transversais , Elasticidade , Feminino , Humanos , Modelos Lineares , Masculino , Manometria , Pessoa de Meia-Idade , Medição de Risco , Fatores de Risco , Distribuição por Sexo , Fatores SexuaisRESUMO
We investigated whether the echocardiographic parameters of the left atrium (LA) can predict the development of nonvalvular atrial fibrillation (AF). Among 14,062 patients (>20 years old) who underwent an echocardiographic examination were evaluated, 2,606 patients who underwent follow-up ECG with an interval of >6 months were investigated. Newly developed AF was noted in 42 (1.6%) patients with follow-up duration of 31.8 +/- 8.9 months. Cox regression analysis revealed that a higher left atrial volume index (hazard ratio [HR]=1.06; 95% confidence interval [CI] 1.03-1.09, P < 0.001), relative wall thickness (RWT) of>or=0.407 (HR=2.74, 95% CI 1.39-5.41, P=0.004), a reduced peak atrial systolic mitral annular velocity (HR=0.845, 95% CI 0.72-0.99, P=0.037), and an advanced age (HR=1.04, 95% CI 1.01-1.07, P=0.009) were independently related to the development of nonvalvular AF. Therefore, reduced A', which is parameter of LA contractile function, might be an important predictor for the development of nonvalvular AF.
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Fibrilação Atrial/diagnóstico por imagem , Ecocardiografia/métodos , Técnicas de Imagem por Elasticidade/métodos , Átrios do Coração/diagnóstico por imagem , Interpretação de Imagem Assistida por Computador/métodos , Valva Mitral/diagnóstico por imagem , Fibrilação Atrial/complicações , Feminino , Doenças das Valvas Cardíacas/complicações , Doenças das Valvas Cardíacas/diagnóstico por imagem , Humanos , Aumento da Imagem/métodos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
OBJECTIVE: To correlate magnetic resonance (MR) image findings with pain response by provocation discography in patients with discogenic low back pain, with an emphasis on the combination analysis of a high intensity zone (HIZ) and disc contour abnormalities. MATERIALS AND METHODS: Sixty-two patients (aged 17-68 years) with axial low back pain that was likely to be disc related underwent lumbar discography (178 discs tested). The MR images were evaluated for disc degeneration, disc contour abnormalities, HIZ, and endplate abnormalities. Based on the combination of an HIZ and disc contour abnormalities, four classes were determined: (1) normal or bulging disc without HIZ; (2) normal or bulging disc with HIZ; (3) disc protrusion without HIZ; (4) disc protrusion with HIZ. These MR image findings and a new combined MR classification were analyzed in the base of concordant pain determined by discography. RESULTS: Disc protrusion with HIZ [sensitivity 45.5%; specificity 97.8%; positive predictive value (PPV), 87.0%] correlated significantly with concordant pain provocation (P < 0.01). A normal or bulging disc with HIZ was not associated with reproduction of pain. Disc degeneration (sensitivity 95.4%; specificity 38.8%; PPV 33.9%), disc protrusion (sensitivity 68.2%; specificity 80.6%; PPV 53.6%), and HIZ (sensitivity 56.8%; specificity 83.6%; PPV 53.2%) were not helpful in the identification of a disc with concordant pain. CONCLUSION: The proposed MR classification is useful to predict a disc with concordant pain. Disc protrusion with HIZ on MR imaging predicted positive discography in patients with discogenic low back pain.
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Deslocamento do Disco Intervertebral/complicações , Deslocamento do Disco Intervertebral/diagnóstico , Dor Lombar/diagnóstico , Dor Lombar/etiologia , Imageamento por Ressonância Magnética/métodos , Adolescente , Adulto , Idoso , Meios de Contraste/administração & dosagem , Feminino , Humanos , Injeções , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Adulto JovemRESUMO
OBJECTIVE: The objective of the study was to compare the diagnostic reliability of 3D US with MR arthrography in diagnosing supraspinatus tendon tears, with arthroscopic findings used as the standard. MATERIALS AND METHODS: In a prospective study 50 patients who later underwent arthroscopic surgery of the rotator cuff were examined pre-operatively by 3D US with MR arthrography. The presence or absence of a full- or partial-thickness supraspinatus tendon tear and the tear size as demonstrated by each imaging and arthroscopy was recorded. The tear size was divided into three grades: small (<1 cm), medium (1-3 cm), and large (>3 cm). RESULTS: The arthroscopic diagnosis was a full-thickness tear in 40 patients, partial-thickness tears in 5, and intact supraspinatus tendon in 5. 3D US correctly diagnosed 35 out of 40 full-thickness tears and MR arthrography 39 out of 40 full-thickness tears. Regarding partial-thickness tears, 3D US underestimated 2 cases as no tear and overestimated 1 case as a full-thickness tear. MR arthrography underestimated 1 case as a partial-thickness tear and overestimated 2 cases as full-thickness and partial-thickness tears respectively. 3D US and MR arthrography yield a sensitivity for full-thickness tears of 87.5% and 97.5% with specificity of 90.0% and 90.0%. Based on the grading system, 3D US measurements correctly predicted the tear size of 23 (65.7%) of the 35 full-thickness tears and MR arthrography 30 (75.0%) of the 39 full-thickness tears. CONCLUSION: Three-dimensional ultrasound seems to be a promising imaging modality comparable to MR arthrography for the assessment of the supraspinatus tendon tears.
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Artroscopia , Imageamento Tridimensional/métodos , Imageamento por Ressonância Magnética/métodos , Lesões do Ombro , Traumatismos dos Tendões/diagnóstico , Ultrassonografia/métodos , Adulto , Idoso , Feminino , Humanos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Articulação do Ombro/diagnóstico por imagem , Articulação do Ombro/patologiaRESUMO
A case of subcutaneous and intramuscular sparganosis was confirmed on surgical excision of a worm in a 60-year-old woman suffering from painful masses in the right thigh. Sonography and MRI revealed an ill-defined intramuscular lesion and multiple cystic lesions in the subcutaneous tissue. At the time of the excision, a sparganum larva was found in the adductor longus muscle. If an intramuscular mass with a serpiginous cystic tract is seen on imaging studies in an endemic area, musculoskeletal sparganosis should be included in the differential diagnosis of a soft tissue tumor.
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Imageamento por Ressonância Magnética , Músculo Esquelético/diagnóstico por imagem , Músculo Esquelético/parasitologia , Esparganose/diagnóstico por imagem , Tela Subcutânea/diagnóstico por imagem , Tela Subcutânea/parasitologia , Animais , Feminino , Humanos , Pessoa de Meia-Idade , Spirometra/fisiologia , UltrassonografiaRESUMO
OBJECTIVE: To describe the sonographic features of cervical recurrence in patient with thyroid cancer and review clinical significance. MATERIALS AND METHODS: Twenty-two consecutive patients with 24 surgically confirmed recurrences undergoing preoperative ultrasonography (US) and US-guided fine needle aspiration biopsy (FNAB) were enrolled. Retrospective analysis was conducted on the sonographic features of recurrence including size, location, shape, echogenicity, multiplicity, laterality relative to initial primary tumor and presence of characteristic findings; cystic change and microcalcification. In addition, review was made on their clinical data including the time interval between the thyroidectomy and the recurrence, serum thyroglobulin (Tg), anti-thyroglobulin antibody (Tg Ab) and 131 iodine whole body scan (IWBS). RESULTS: Fifteen of 24 recurrences occurred in internal jugular lymphatic chain and 9 in the postoperative paratracheal region with mostly ipsilaterally to the initial tumor (19/24). Their mean size was 1.0 cm (range: 0.5-2.5 cm) with ovoid (n=18) or lobulated (n=6) shape. They appeared hyperechoic in nine (37.5%), hypoechoic in nine (37.5%), and mixed echoic due to cystic change in six (25.0%). Microcalcification was observed in eight (33.3%) and multiplicity in seven (29.2%). US-guided FNAB established the preoperative diagnosis of recurrence in all. The mean interval between the thyroidectomy and recurrence was 59 months (range: 15-162 months). Suspicion of recurrence was possible in 8 with Tg of 2 ng/ml or greater (8/24) during thyroxine (T4) therapy and 6 (6/8) after T4 withdrawal. All of the 8 recurrences were negative on 131 IWBS. In two patients with Tg less than 2 ng/ml after T4 withdrawal, elevated Tg Ab was observed. CONCLUSION: US and US-guided FNAB are valuable postoperative follow up modalities of thyroid cancer due to their convenience, early detection and precise localization. Therefore, it's essential to get familiar with sonographic findings of cervical recurrence.
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Recidiva Local de Neoplasia/diagnóstico por imagem , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Tireoidectomia , Adulto , Idoso , Autoanticorpos/sangue , Biomarcadores Tumorais/sangue , Biópsia por Agulha Fina , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/cirurgia , Tireoglobulina/sangue , Glândula Tireoide/diagnóstico por imagem , Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/cirurgia , Tiroxina/uso terapêutico , UltrassonografiaRESUMO
OBJECT: The authors evaluate the biomechanical properties of vertebral bodies (VBs) stabilized with calcium phosphate (CaP) cements for use in vertebroplasty in comparison with polymethylmethacrylate (PMMA). METHODS: In the first phase of the study, 73 VBs (T3-L2; thoracic region [T3-8] and thoracolumbar region [T9-L2]) were collected from seven fresh human cadavers. Compression tests were performed before and after vertebroplasty using PMMA (compression strength 80 MPa) and three kinds of CaP cements-CaP1 (5 MPa), CaP2 (20 MPa), and CaP3 (50 MPa). The authors compared the maximal compression loads (MCLs) and stiffness before and after vertebroplasty in each of the four cement groups. In the second phase of the study, 18 paired spinal units (PSUs) were collected from three fresh human cadavers, and the authors injected two types of cement selected from the first phase of the study into the lower level of six PSUs. They compared the MCLs of the untreated and two treated groups (there were six PSUs in each type of group) to analyze the tendency of inducing compression fractures in the upper level of the PSUs. The MCLs of the PMMA-injected vertebrae were significantly increased after vertebroplasty. The MCL levels of the CaP3-injected vertebrae and the CaP2-injected thoracolumbar vertebrae were decreased from those of untreated vertebrae without being significant. The MCLs of CaP1-injected vertebrae and CaP2-injected thoracic vertebrae were significantly decreased after vertebroplasty. The stiffness of all cement groups was decreased after vertebroplasty compared with initial stiffness, significantly so in all three thoracic CaP groups. In the second compression test with PSUs, the MCLs of the CaP2- and CaP3-injected PSUs were not significantly different from those of the untreated control PSUs. CONCLUSIONS: The CaP3-injected vertebrae restored the MCLs of human vertebrae closer to their initial levels than the PMMA-injected vertebrae did. The CaP2- and CaP3-injected PSUs showed no tendency to induce compression fractures in adjacent VBs.
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Cimentos Ósseos/uso terapêutico , Fosfatos de Cálcio/uso terapêutico , Fraturas por Compressão/terapia , Idoso , Idoso de 80 Anos ou mais , Fenômenos Biomecânicos , Cadáver , Fosfatos de Cálcio/administração & dosagem , Força Compressiva , Feminino , Humanos , Instabilidade Articular , Vértebras Lombares , Masculino , Teste de Materiais , Pessoa de Meia-Idade , Vértebras TorácicasRESUMO
BACKGROUND/AIMS: Protein induced by vitamin K absence or antagonist-II (PIVKA-II), also known as des-carboxyprothrombin (DCP), can be used as an alternative tool to alpha-fetoprotein (AFP) for surveillance of hepatocellular carcinoma (HCC). The aims of the present study were to compare PIVKA-II levels between the patients with HCC and patients with non-HCC chronic liver disease, to evaluate the correlation of PIVKA-II and AFP in HCC patients, and finally to estimate the optimal cut-off value for PIVKA-II for the diagnosis of HCC with using the receiver operating characteristic (ROC) curve. METHODS: A total of 227 consecutive patients with HCC (n=42) or chronic liver disease (n=185) were enrolled in this study. HCC was diagnosed histologically or by imaging such as computed tomography, magnetic resonance imaging or angiography. The serum PIVKA-II and AFP levels were measured by electrochemiluminoimmunoassay with using the Haicatch PIVKA-II kit and by immunoradiometric assay, respectively. RESULTS: The PIVKA-II level in the HCC patients was significantly higher than the non-HCC chronic liver disease patients (903.0+/-1156.7 vs. 111.7+/-211.0 mAU/ mL, respectively, P<0.01). PIVKA-II and AFP showed a statistical correlation in HCC patients (r=0.46, P<0.01). The sensitivity and specificity of PIVKA-II for the diagnosis of HCC were 66.7% and 74.1%, respectively, and when tasted together with AFP, the sensitivity was increased by 85.7%. For the ROC curve of PIVKA-II in HCC patients, the specificity of a 250 mAU/mL level of PIVKA-II was 95%. CONCLUSIONS: PIVKA-II was as useful surveillance tool for differentiating HCC from chronic liver disease, and a PIVKA-II value of 250 mAU/ mL was proposed as a significant cut-off value for diagnosis of hepatocellular carcinoma.
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Biomarcadores Tumorais/sangue , Biomarcadores/sangue , Carcinoma Hepatocelular/diagnóstico , Neoplasias Hepáticas/diagnóstico , Precursores de Proteínas/sangue , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Protrombina , Curva ROC , alfa-Fetoproteínas/análiseRESUMO
Castleman's disease is a rare benign lymphoproliferative disorder of uncertain origin which most commonly involves the mediastinum but rarely affects the axilla. We report a case of localized Castleman's disease involving the axillary lymph node. Mammography revealed a well-defined, homogeneously dense ovoid mass, 3 cm in size, in the left axilla, while gray-scale ultrasonography (US) demonstrated a well-defined, uniformly hypoechoic ovoid mass with good through transmission. Peripheral hypervascularity was observed at power Dopper US, and early rapid homogeneous enhancement at contrast-enhanced dynamic CT.
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Hiperplasia do Linfonodo Gigante/diagnóstico , Linfonodos/patologia , Tomografia Computadorizada por Raios X , Ultrassonografia Doppler , Axila , Hiperplasia do Linfonodo Gigante/diagnóstico por imagem , Feminino , Humanos , Pessoa de Meia-IdadeRESUMO
OBJECTIVE: To compare the use of conventional, real-time compound, and pulse-inversion harmonic imaging in the evaluation of breast nodules. MATERIALS AND METHODS: Fifty-two breast nodules were included in this study, conducted between May and December 2000, in which conventional, real-time compound, and pulse-inversion harmonic images were obtained in the same plane. Three radiologists, each blinded to the interpretations of the other two, evaluated the findings, characterizing the lesions and ranking the three techniques from grade 1, the worst, to grade 3, the best. Lesion conspicuity was assessed, and lesions were also characterized in terms of their margin, clarity of internal echotexture, and clarity of posterior echo pattern. The three techniques were compared using Friedman's test, and interobserver agreement in image interpretation was assessed by means of the intraclass correlation coefficient. RESULTS: With regard to lesion conspicuity, margin, and internal echotexture of the nodules, real-time compound imaging was the best technique (p < 0.05); in terms of posterior echo pattern, the best was pulse-inversion harmonic imaging (p < 0.05). Real-time compound and pulse inversion harmonic imaging were better than conventional sonography in all evaluative aspects. Interobserver agreement was greater than moderate. CONCLUSION: Real-time compound and pulse-inversion harmonic imaging procedures are superior to conventional sonography in terms of both lesion conspicuity and the further characterization of breast nodules. Real-time compound imaging is the best technique for evaluation of the margin and internal echotexture of nodules, while pulse-inversion harmonic imaging is very effective for the evaluation of the posterior echo patterns.
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Neoplasias da Mama/diagnóstico por imagem , Doença da Mama Fibrocística/diagnóstico por imagem , Ultrassonografia Mamária/métodos , Feminino , Humanos , Pessoa de Meia-IdadeRESUMO
This paper reports for the first time the luminescent property of polystyrene (PS), produced by pulsed ultra violet laser irradiation. We have discovered that, in air, ultra-violet (UV) irradiated PS nanospheres emit bright white light with the dominant peak at 510 nm, while in vacuum they emit in the near-blue region. From the comparison of PS nanospheres irradiated in vacuum and air, we suggest that the white luminescence is due to the formation of carbonyl groups on the surface of PS by photochemical oxidation. Our results potentially offer a new route and strategy for white light sources.
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Stent migration from the delivery balloon catheter is a rare but serious complication during percutaneous coronary intervention, particularly when a part of the stent stretches into the aorta. We report an unusual case of stent migration treated with a combination of a gooseneck snare and rotablation. A part of the stent was overstretched and unrolled into the aorta and the rest of the stent remained implanted in the coronary artery. The stent was captured with a gooseneck snare but could not be retrieved because it was connected to a stent remnant implanted in the coronary artery. The stent strut was cut with rotablation, and the stent was successfully removed through the femoral sheath.
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OBJECTIVES/HYPOTHESIS: The purpose of this study was to determine the appropriate cut-off value for fine needle aspiration-thyroglobulin (FNA-Tg) associated with postoperative recurrences and validate the diagnostic efficacy of FNA-Tg in patients after total thyroidectomy compared with concomitant cytology (C). STUDY DESIGN: Retrospective. METHODS: We retrospectively evaluated the results of ultrasound-guided FNAs performed for suspicious cervical lesions of 40 patients (male:female = 10:30; mean age, 44.0 years) after total thyroidectomy (mean duration, 89.1 months), to acquire the material for Tg and C analysis. After collection of the cytologic sample, we rinsed the same needle with 1 mL of normal saline for Tg radioimmunoassay. RESULTS: Of 40 lesions (mean size, 0.89 cm; range, 0.3-3.5 cm), 21 were confirmed as recurrences and 19 were nonrecurrences. The rates of nondiagnostic sampling and sensitivity and specificity of FNA-C when diagnostic sampling was obtained were 40% (16/40), 100% (14/14), and 90.0% (9/10), respectively. According to receiver operating characteristic analysis, the optimal cut-off value of FNA-Tg was 4.1 ng/mL (sensitivity, 100% [21/21]; specificity, 100% [19/19], P < .05). Furthermore, in 16 inconclusive lesions due to nondiagnostic cytologic results, the FNA-Tg results coincided with a final diagnosis (seven recurrences and nine nonrecurrences). The cases with maximum diameters <1 cm showed a significantly increased rate of nondiagnostic cytologic results, and the FNA-Tg results were more helpful than lesions > or =1 cm in diagnosing a recurrence (P < .05). CONCLUSIONS: Measurement of FNA-Tg is helpful for distinguishing recurrent from nonrecurrent lesions in the majority of patients who were previously treated for well-differentiated papillary thyroid carcinoma.
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Carcinoma Papilar/patologia , Recidiva Local de Neoplasia/patologia , Tireoglobulina , Neoplasias da Glândula Tireoide/patologia , Adulto , Idoso , Carcinoma Papilar/diagnóstico por imagem , Carcinoma Papilar/cirurgia , Distribuição de Qui-Quadrado , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/diagnóstico por imagem , Curva ROC , Radioimunoensaio , Estudos Retrospectivos , Sensibilidade e Especificidade , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/cirurgia , Tireoidectomia , Ultrassonografia de IntervençãoRESUMO
PURPOSE: To analyze the discrepancies between the cytologic results of sonographically (US)-guided fine needle aspiration (FNA) of thyroid nodules and final histopathologic results and to discuss the limitations of US-guided FNA. MATERIALS AND METHODS: The results of US-guided FNAs performed by a single experienced radiologist in 315 thyroid nodules in 292 patients (246 women, 46 men aged 12-79 years) were retrospectively correlated with their surgical pathologic results. The FNA results were classified as nondiagnostic, indeterminate, negative, or positive, whereas final pathologic diagnoses were classified as malignant or benign. RESULTS: The FNA results were nondiagnostic in 31 cases (9.8%), indeterminate in 97 cases (30.8%), and determinate in 187 cases (59.4%). Of the 187 conclusive cases, 169 (90.4%) were concordant with the final pathologic results, whereas 18 (9.6%) were discordant with 14 false-positive and 4 false-negative results. These discrepancies were caused by atypical nuclear features. Among the 97 indeterminate and 31 nondiagnostic cases, a malignancy was found in 14 (14.4%) and 8 (25.8%) cases, respectively. In addition, 10 papillary carcinomas, which were not visualized on sonograms, were detected incidentally in thyroidectomy specimens. CONCLUSION: The diagnostic accuracy of US-guided FNA of thyroid nodule has limitations that should be minimized by careful interpretation of the cytologic findings and accurate sampling.