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1.
Quant Imaging Med Surg ; 9(11): 1773-1780, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31867231

RESUMEN

BACKGROUND: Ultrasound is a common imaging method for assessment of cervical lymph nodes. However, metastatic and tuberculous lymph nodes have similar sonographic features in routine ultrasound examination. Computer-aided assessment could be a potential adjunct to enhance the accuracy of differential diagnosis. METHODS: Gray-scale and power Doppler sonograms of 100 patients with palpable cervical lymph nodes were reviewed and analyzed (60 metastatic nodes, 40 tuberculous nodes). Final diagnosis of lymph nodes was based on fine needle aspiration and cytology. Sonograms were reviewed and assessed for nodal shape, echogenic hilus, intranodal necrosis and vascular distribution (conventional assessment). Intranodal vascularity was quantified using a customized computer algorithm to determine vascularity index (VI). The diagnostic accuracy of using conventional assessment and its combination with intranodal VI method was evaluated and compared. RESULTS: Metastatic and tuberculous nodes tended to be round (75.0% vs. 50.0%), without echogenic hilus (86.7% vs. 72.5%) and have peripheral vascularity (73.3% vs. 85.0%). Intranodal necrosis is more common in tuberculous nodes (27.5%) than metastatic nodes (8.3%). Using conventional assessment in differentiating metastatic and tuberculous nodes, the diagnostic accuracy was 56% with a sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of 56.7%, 55%, 65.4% and 45.8% respectively. The VI of metastatic nodes (23.4%±2.1%) was significantly higher than that of tuberculous nodes (12.0%±1.6%) (P<0.05). The optimum cut-off of VI for the differential diagnosis was 20%. By combining conventional assessment and intranodal VI quantification, the diagnostic accuracy was increased to 69% with a sensitivity, specificity, PPV and NPV of 80%, 52.5%, 71.6%, 63.6% respectively. The increase in sensitivity was statistically significant (P=0.006). CONCLUSIONS: Computer-aided quantification of intranodal vascularity provides added value in routine ultrasound assessment of cervical lymph nodes. It enhances the accuracy of ultrasound in distinguishing metastatic and tuberculous cervical lymph nodes.

2.
Biomed Opt Express ; 10(7): 3584-3590, 2019 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-31467795

RESUMEN

Silicone gel sheeting (SGS) is widely used for scar treatment; however, studies showing its interaction with skin and efficacy of scar treatment are still lacking. THz light is non-ionizing and highly sensitive to changes in water content and thus skin hydration. In this work, we use in-vivo THz imaging to monitor how SGS affects the THz response of human skin during occlusion, and the associated THz reflectivity and refractive index changes are presented. We find that SGS effectively hydrates the skin beneath it, with minimal lateral effects beyond the sheeting. Our work demonstrates that THz imaging is able to detect the subtle hydration changes on the surface of human skin caused by SGS, and it has the potential to be used to evaluate different scar treatment strategies.

3.
Eur Radiol ; 29(10): 5627-5634, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30903340

RESUMEN

OBJECTIVES: MRI can detect early-stage nasopharyngeal carcinoma (NPC), but the detection is more challenging in early-stage NPCs because they must be distinguished from benign hyperplasia in the nasopharynx. This study aimed to determine whether intravoxel incoherent motion diffusion-weighted imaging (IVIM DWI) MRI could distinguish between these two entities. METHODS: Thirty-four subjects with early-stage NPC and 30 subjects with benign hyperplasia prospectively underwent IVIM DWI. The mean pure diffusion coefficient (D), pseudo-diffusion coefficient (D*), perfusion fraction (f) and apparent diffusion coefficient (ADC) values were calculated for all subjects and compared between the 2 groups using Student's t test. Receiver operating characteristics with the area under the curve (AUC) was used to identify the optimal threshold for all significant parameters, and the corresponding diagnostic performance was calculated. A p value of < 0.05 was considered statistically significant. RESULTS: Compared with benign hyperplasia, early-stage NPC exhibited a significantly lower D mean (0.64 ± 0.06 vs 0.87 ± 0.11 × 10-3 mm2/s), ADC0-1000 mean (0.77 ± 0.08 vs 1.00 ± 0.13 × 10-3 mm2/s), ADC300-1000 (0.63 ± 0.05 vs 0.86 ± 0.10 × 10-3 mm2/s) and a higher D* mean (32.66 ± 4.79 vs 21.96 ± 5.21 × 10-3 mm2/s) (all p < 0.001). No significant difference in the f mean was observed between the two groups (p = 0.216). The D and ADC300-1000 mean had the highest AUC of 0.985 and 0.988, respectively, and the D mean of < 0.75 × 10-3 mm2/s yielded the highest sensitivity, specificity and accuracy (100%, 93.3% and 96.9%, respectively) in distinguishing early-stage NPC from benign hyperplasia. CONCLUSION: DWI has potential to distinguish early-stage NPC from benign hyperplasia and D and ADC300-1000 mean were the most promising parameters. KEY POINTS: • Diffusion-weighted imaging has potential to distinguish early-stage nasopharyngeal carcinoma from benign hyperplasia in the nasopharynx. • The pure diffusion coefficient, pseudo-diffusion coefficient from intravoxel incoherent motion model and apparent diffusion coefficient from conventional diffusion-weighted imaging were significant parameters for distinguishing these two entities in the nasopharynx. • The pure diffusion coefficient, followed by apparent diffusion coefficient, may be the most promising parameters to be used in screening studies to help detect early-stage nasopharyngeal carcinoma.


Asunto(s)
Imagen de Difusión por Resonancia Magnética/métodos , Detección Precoz del Cáncer/métodos , Carcinoma Nasofaríngeo/diagnóstico , Neoplasias Nasofaríngeas/diagnóstico , Estadificación de Neoplasias/métodos , Adulto , Anciano , Anciano de 80 o más Años , Diagnóstico Diferencial , Femenino , Humanos , Hiperplasia/diagnóstico , Masculino , Persona de Mediana Edad , Enfermedades Nasofaríngeas/diagnóstico , Curva ROC , Reproducibilidad de los Resultados
4.
Oral Oncol ; 88: 124-130, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30616782

RESUMEN

PURPOSE: Extranodal extension (ENE) is a criterion for advanced nodal staging of oropharyngeal and hypopharyngeal carcinoma. Our aim was to determine if ENE should be a staging criterion for nasopharyngeal carcinoma (NPC). MATERIALS & METHODS: MRI of 546 NPC patients were reviewed retrospectively and in 404/546 (74.0%) with metastatic nodes, the nodes were assessed for ENE (grade 0 = absent; grade 1 = infiltration of surrounding fat; grade 2 = infiltration of muscle/skin), size (total volume), site (unilateral/bilateral and upper/lower neck) and necrosis. Associations between nodal features and regional relapse free survival (RRFS), distant metastases free survival (DMFS) and overall survival (OS) were assessed using cox regression. Differences of survival rates were compared using log-rank test. A p-value of < 0.05 indicates statistical significance. RESULTS: ENE grade was the only determinant of RRFS (p = 0.014) and only independent determinant of DMFS (p = 0.003) and OS (p < 0.001). Grade 2 ENE was associated with significantly poorer RRFS, DMFS and OS compared to grade 0 and 1 (p < 0.05). Addition of grade 2 ENE to N1 and N2 disease showed similar poor RRFS, DMFS and OS to N3 disease (p > 0.05). Compared to the current stage N3 disease, inclusion of grade 2 ENE increased the number of N3 patients from 53/546 (9.7%) to 82/546 (15.0%) with similar hazard ratios for DMFS (6.855 and 7.125, respectively) and OS (3.614 and 4.085, respectively). CONCLUSION: Grade 2 ENE (into muscle and/or skin and/or salivary glands) is an independent indicator of poor outcome and may be considered as a new criterion for N3 nodal disease in NPC.


Asunto(s)
Extensión Extranodal , Metástasis Linfática/diagnóstico por imagen , Metástasis Linfática/patología , Carcinoma Nasofaríngeo/diagnóstico por imagen , Carcinoma Nasofaríngeo/patología , Neoplasias Nasofaríngeas/diagnóstico por imagen , Neoplasias Nasofaríngeas/patología , Adulto , Anciano , Anciano de 80 o más Años , Supervivencia sin Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Ganglios Linfáticos/diagnóstico por imagen , Ganglios Linfáticos/patología , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Carcinoma Nasofaríngeo/mortalidad , Neoplasias Nasofaríngeas/mortalidad , Invasividad Neoplásica/diagnóstico por imagen , Invasividad Neoplásica/patología , Estadificación de Neoplasias , Pronóstico , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Tasa de Supervivencia , Carga Tumoral , Adulto Joven
5.
J Biophotonics ; 12(2): e201800145, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-29989386

RESUMEN

Water diffusion and the concentration profile within the skin significantly affect the surrounding chemical absorption and molecular synthesis. Occluding the skin causes water to accumulate in the top layer of the skin (the stratum corneum [SC]) and also affects the water diffusivity. Scar treatments such as silicone gel and silicone sheets make use of occlusion to increase skin hydration. However with existing techniques, it is not possible to quantitatively measure the diffusivity of the water during occlusion: current methods determine water diffusivity by measuring the water evaporated through the skin and thus require the skin to breathe. In this work, we use the high sensitivity of terahertz light to water to study how the water content in the SC changes upon occlusion. From our measurements, we can solve the diffusion equations in the SC to deduce the water concentration profile in occluded skin and subsequently to determine the diffusivity. To our knowledge, this is the first work showing how the diffusivity of human skin can be measured during occlusion and we envisage this paper as being used as a guide for non-invasively determining the diffusivity of occluded human skin in vivo.


Asunto(s)
Piel/metabolismo , Espectroscopía de Terahertz , Agua/metabolismo , Difusión , Humanos , Fenómenos Ópticos
6.
Eur Arch Otorhinolaryngol ; 276(2): 505-512, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30511106

RESUMEN

PURPOSE: To determine if treatment of nasopharyngeal carcinoma (NPC) induces early changes in amide proton transfer-weighted (APTw) magnetic resonance imaging (MRI), and to perform a preliminary evaluation of APTw imaging in response assessment. METHODS: Sixteen patients with NPC planned for treatment with radiotherapy and/or chemotherapy underwent APTw imaging of the primary tumour pre-treatment and 2-week intra-treatment. Difference in pre- and intra-treatment APT mean (APTmean) was compared using the Wilcoxon signed rank test. Differences in APTmean and percentage change (%Δ) in APTmean were compared between responders and non-responders based on the outcome at 6 months, using the Mann-Whitney U test. RESULTS: APTmean decreased in 9/16 (56.3%) and increased in 7/16 (43.7%) with no significant difference between the pre- and intra-treatment APT values for the whole group (p > 0.05). NPC showed response in 11/16 (68.8%) and non-response in 5/11 (31.2%). There were significant differences between the %Δ of responders and non-responders for APTmean (p = 0.01). Responders showed %Δ decrease in APTmean of - 23.12% while non-responders showed a %Δ increase in APTmean of + 102.28%. CONCLUSION: APT value changes can be detected in early intra-treatment. Intra-treatment %Δ APTmean shows potential in predicting short-term outcome.


Asunto(s)
Imagen por Resonancia Magnética/métodos , Carcinoma Nasofaríngeo/diagnóstico por imagen , Adulto , Anciano , Amidas , Quimioradioterapia , Femenino , Humanos , Masculino , Persona de Mediana Edad , Carcinoma Nasofaríngeo/patología , Carcinoma Nasofaríngeo/terapia , Terapia Neoadyuvante , Estudios Prospectivos , Protones
7.
J Clin Oncol ; : JCO2018777847, 2018 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-29989858

RESUMEN

Purpose The contribution of adjuvant chemotherapy after chemoradiation therapy (CRT) in nasopharyngeal cancer (NPC) remains controversial. Plasma Epstein-Barr virus (EBV) DNA is a potential biomarker of subclinical residual disease in NPC. In this prospective, multicenter, randomized controlled trial, we used plasma EBV DNA to identify patients with NPC at a higher risk of relapse for adjuvant chemotherapy. Patients and Methods Eligible patients with histologically confirmed NPC of Union for International Cancer Control stage IIB to IVB, adequate organ function, and no locoregional disease or distant metastasis were screened by plasma EBV DNA at 6 to 8 weeks after radiotherapy (RT). Patients with undetectable plasma EBV DNA underwent standard surveillance. Patients with detectable plasma EBV DNA were randomly assigned to either adjuvant chemotherapy with cisplatin and gemcitabine for six cycles (arm 1) or observation (arm 2). Patients were stratified for primary treatment (RT v CRT) and stage (II/III v IV). The primary end point was relapse-free survival (RFS). Results Seven hundred eighty-nine patients underwent EBV DNA screening. Plasma EBV DNA was undetectable in 573 (72.6%) and detectable in 216 (27.4%); 104 (13.2%) with detectable EBV DNA were randomly assigned to arms 1 (n = 52) and 2 (n = 52). After a median follow-up of 6.6 years, no significant difference was found in 5-year RFS rate between arms 1 and 2 (49.3% v 54.7%; P = .75; hazard ratio for relapse or death, 1.09; 95% CI, 0.63 to 1.89). The level of post-RT plasma EBV DNA correlated significantly with the hazards of locoregional failure, distant metastasis, and death. Conclusion In patients with NPC with detectable post-RT plasma EBV DNA, adjuvant chemotherapy with cisplatin and gemcitabine did not improve RFS. Post-RT plasma EBV DNA level should be incorporated as the selection factor in future clinical trials of adjuvant therapy in NPC.

8.
Radiology ; 288(3): 782-790, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29893646

RESUMEN

Purpose To evaluate the utility of amide proton transfer (APT) imaging in the characterization of head and neck tumors. Materials and Methods This retrospective study of APT imaging included 117 patients with 70 nasopharyngeal undifferentiated carcinomas (NUCs), 26 squamous cell carcinomas (SCCs), eight non-Hodgkin lymphomas (NHLs), and 13 benign salivary gland tumors (BSGTs). Normal tissues were examined in 25 patients. The APT means of malignant tumors, normal tissues, and benign tumors were calculated and compared with the Student t test and analysis of variance. The added value of the mean APT to the mean apparent diffusion coefficient (ADC) for differentiating malignant and benign tumors was evaluated by using receiver operating characteristic analysis and integrated discrimination index. Results The mean APT of malignant tumors (2.40% ± 0.97 [standard deviation]) was significantly higher than that of brain tissue (1.13% ± 0.43), muscle tissue (0.23% ± 0.73), and benign tumors (1.32% ± 1.20) (P < .001). There were no differences between malignant groups (NUC, 2.37% ± 0.90; SCC, 2.41% ± 1.16; NHL, 2.65% ± 0.89; P = .45 to P = .86). The mean ADC of malignant tumors ([0.85 ± 0.17] × 10-3 mm2/sec) was significantly lower than that of benign tumors ([1.46 ± 0.47] × 10-3 mm2/sec) (P = .001). Adding APT to ADC increased the area under the curve from 0.87 to 0.96, with an integrated discrimination index of 7.6% (P = .13). Conclusion These preliminary data demonstrate differences in amide proton transfer (APT) mean of malignant tumors, normal tissues, and benign tumors, although APT mean could not be used to differentiate between malignant tumor groups. APT imaging has the potential to be of added value to apparent diffusion coefficient in differentiating malignant from benign tumors.


Asunto(s)
Carcinoma de Células Escamosas/diagnóstico por imagen , Neoplasias de Cabeza y Cuello/diagnóstico por imagen , Linfoma no Hodgkin/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma/diagnóstico por imagen , Diagnóstico Diferencial , Femenino , Cabeza/diagnóstico por imagen , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Masculino , Persona de Mediana Edad , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/diagnóstico por imagen , Cuello/diagnóstico por imagen , Protones , Reproducibilidad de los Resultados , Estudios Retrospectivos , Neoplasias de las Glándulas Salivales/diagnóstico por imagen , Sensibilidad y Especificidad , Adulto Joven
9.
Laryngoscope ; 128(11): 2552-2559, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-29668108

RESUMEN

OBJECTIVES/HYPOTHESIS: Ultrasonography is an emerging clinical tool to study the dysfunction of swallowing muscles. This was the first sonographic study to assess the relationship between suprahyoid muscle contraction, hyoid bone displacement, and penetration-aspiration status (PAS) during swallowing in nasopharyngeal carcinoma (NPC) patients treated with radiotherapy (RT). The study also aimed to establish reliability data for the sonographic technique described. STUDY DESIGN: Cross-sectional study. METHODS: Geniohyoid muscle contraction was quantified using brightness-mode ultrasonography in this study of 40 post-RT NPC patients. A series of physiological parameters and PAS were measured using videofluoroscopy. RESULTS: Intra- and inter-rater agreement values ranged from 0.75 to 0.96 across various sonographic measurements. Percentage increase in the cross-sectional area of the geniohyoid muscle correlated with anterior (r = 0.42, P < .05) but not superior (r = 0.27, P = .09) hyoid displacement. Anterior hyoid displacement and pharyngeal constriction ratio were significantly associated with PAS score. CONCLUSIONS: Sonographic measurement of suprahyoid muscles provides valuable information on muscle function and is potentially a useful clinical tool in swallowing assessment. Further research is needed to refine the role of this examination in dysphagia. LEVEL OF EVIDENCE: 2b. Laryngoscope, 2552-2559, 2018.


Asunto(s)
Trastornos de Deglución/diagnóstico por imagen , Trastornos de Deglución/fisiopatología , Carcinoma Nasofaríngeo/radioterapia , Ultrasonografía/métodos , Adulto , Anciano , Anciano de 80 o más Años , Estudios Transversales , Humanos , Hueso Hioides/diagnóstico por imagen , Hueso Hioides/fisiopatología , Masculino , Persona de Mediana Edad , Músculos del Cuello/diagnóstico por imagen , Músculos del Cuello/fisiopatología , Reproducibilidad de los Resultados
10.
Clin Cancer Res ; 24(5): 1030-1037, 2018 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-29301831

RESUMEN

Purpose: We hypothesized that axitinib is active with an improved safety profile in nasopharyngeal carcinoma (NPC).Experimental Design: We evaluated axitinib in preclinical models of NPC and studied its efficacy in a phase II clinical trial in recurrent or metastatic NPC patients who progressed after at least one line of prior platinum-based chemotherapy. We excluded patients with local recurrence or vascular invasion. Axitinib was started at 5 mg twice daily in continuous 4-week cycles. Primary endpoint was clinical benefit rate (CBR), defined as the percentage of patients achieving complete response, partial response, or stable disease by RECIST criteria for more than 3 months.Results: We recruited 40 patients, who received a median of 3 lines of prior chemotherapy. Axitinib was administered for a mean of 5.6 cycles, with 16 patients (40%) receiving ≥6 cycles. Of 37 patients evaluable for response, CBR was 78.4% (95% CI, 65.6%-91.2%) at 3 months and 43.2% (30.4%-56.1%) at 6 months. Grade 3/4 toxicities were uncommon, including hypertension (8%), diarrhea (5%), weight loss (5%), and pain (5%). All hemorrhagic events were grade 1 (15%) or grade 2 (3%). Elevated diastolic blood pressure during the first 3 months of axitinib treatment was significantly associated with improved overall survival (HR, 0.29; 95% CI, 0.13-0.64, P = 0.0012). Patient-reported fatigue symptom was associated with hypothyroidism (P = 0.039). Axitinib PK parameters (Cmax and AUC(0-t)) were significantly correlated with tumor response, toxicity, and serum thyroid-stimulating hormone changes.Conclusions: Axitinib achieved durable disease control with a favorable safety profile in heavily pretreated NPC patients. Clin Cancer Res; 24(5); 1030-7. ©2018 AACR.


Asunto(s)
Antineoplásicos/administración & dosificación , Axitinib/administración & dosificación , Carcinoma Nasofaríngeo/tratamiento farmacológico , Neoplasias Nasofaríngeas/tratamiento farmacológico , Recurrencia Local de Neoplasia/tratamiento farmacológico , Adulto , Anciano , Animales , Antineoplásicos/efectos adversos , Antineoplásicos/farmacocinética , Axitinib/efectos adversos , Axitinib/farmacocinética , Línea Celular Tumoral , Diarrea/inducido químicamente , Diarrea/epidemiología , Progresión de la Enfermedad , Esquema de Medicación , Fatiga/inducido químicamente , Fatiga/epidemiología , Femenino , Hemorragia/inducido químicamente , Hemorragia/epidemiología , Humanos , Hipertensión/inducido químicamente , Hipertensión/epidemiología , Concentración 50 Inhibidora , Masculino , Ratones , Persona de Mediana Edad , Carcinoma Nasofaríngeo/sangre , Carcinoma Nasofaríngeo/patología , Neoplasias Nasofaríngeas/sangre , Neoplasias Nasofaríngeas/patología , Recurrencia Local de Neoplasia/sangre , Recurrencia Local de Neoplasia/patología , Dolor/inducido químicamente , Dolor/epidemiología , Criterios de Evaluación de Respuesta en Tumores Sólidos , Tirotropina/sangre , Pérdida de Peso/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto , Adulto Joven
11.
Biomed Opt Express ; 9(12): 6467-6476, 2018 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-31065443

RESUMEN

Terahertz (THz) light is non-ionizing and highly sensitive to subtle changes in water concentration which can be indicative of disease. The short THz penetration depth in bio-samples restricts in vivo measurements to be in a reflection geometry and the sample is often placed onto an imaging window. Upon contacting the imaging window, occlusion and compression of the skin affect the THz response. If not appropriately controlled, this could cause misleading results. In this work, we investigate and quantify how the applied pressure affects the THz response of skin and employ a stratified model to help understand the mechanisms at play. This work will enable future THz studies to have a more rigorous experimental protocol, which in turn will facilitate research in various potential biomedical applications under investigation.

12.
Eur Arch Otorhinolaryngol ; 274(2): 1045-1051, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27722898

RESUMEN

Our study aimed to identify diffusion-weighted imaging (DWI) parameters obtained from primary nasopharyngeal carcinoma (NPC) at initial presentation, that can predict patients at risk of distant metastases. One hundred and sixty-four patients underwent pretreatment magnetic resonance imaging and DWI. The apparent diffusion coefficient (ADC)mean, ADCskewness, and ADCkurtosis were obtained by histogram analysis. Univariate and multivariate analyses of these ADC parameters together with primary volume (PV), nodal volume (NV), T stage, N stage and presence of locoregional relapse (LRR) were compared between patients with distant metastases (DM+) and patients without distant metastases (DM-) at 5 years using logistic regression. Twenty-eight out of 164 patients (17.1 %) were DM+ (2.5-60 months) and 136/164 patients were DM- (61.2-119.4 months). Compared to DM- patients, the primary tumour of DM+ patients showed significantly lower ADCskewness (ADC values with the greatest frequency were higher) (p = 0.041), and higher PV (p = 0.022), NV (p < 0.01), T stage (p = 0.023), N stage (p < 0.01) and LRR (p < 0.01). On multivariate analysis the ADCskewness was no longer significant (p = 0.120) and only NV and LRR were independent predictors for DM+ (p = 0.023 and 0.021, respectively). DWI showed that compared to DM- patients, DM+ patients had a significantly lower primary tumour ADCskewness, but at initial presentation NV was the only independent predictor of DM.


Asunto(s)
Imagen de Difusión por Resonancia Magnética/métodos , Neoplasias Nasofaríngeas/diagnóstico , Neoplasias Nasofaríngeas/secundario , Nasofaringe/diagnóstico por imagen , Estadificación de Neoplasias/métodos , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma , Femenino , Humanos , Masculino , Persona de Mediana Edad , Carcinoma Nasofaríngeo , Metástasis de la Neoplasia , Valor Predictivo de las Pruebas
13.
J Neuropsychiatry Clin Neurosci ; 29(2): 172-178, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-27707197

RESUMEN

The role of the infarct location in the development of poststroke agitation (PSA) is largely unknown. This study examined the association between the locations of infarcts and PSA at 9 months following the index stroke in 213 patients with the Chinese version of the Neuropsychiatric Inventory. Compared with the non-PSA group, PSA patients had a higher number and volume of acute pontine infarcts. Ventral pontine and lateral cerebellar infarcts were independent predictors of PSA in the multivariate analysis.


Asunto(s)
Agresión , Infarto Encefálico/diagnóstico por imagen , Infarto Encefálico/etiología , Imagen por Resonancia Magnética , Agitación Psicomotora/etiología , Accidente Cerebrovascular/complicaciones , Anciano , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Persona de Mediana Edad , Vías Nerviosas/diagnóstico por imagen , Puente/diagnóstico por imagen , Escalas de Valoración Psiquiátrica , Agitación Psicomotora/diagnóstico por imagen , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/psicología
14.
Indian J Radiol Imaging ; 26(3): 405-410, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27857471

RESUMEN

AIM: To evaluate the efficacy of 18flurodeoxyglucose positron emission tomography/computer tomography (18F-FDG PET/CT) in investigating patients with elevated carcinoembryonic antigen (CEA) and without known primary malignancy, and the impact of PET/CT findings on patient management. SETTING AND DESIGN: PET/CT scans done in a tertiary hospital between December 2007 and February 2012 for elevated CEA in patients without known primary malignancy were retrospectively reviewed. MATERIALS AND METHODS: The PET/CT findings, patients' clinical information, level of CEA, histological diagnosis, and subsequent management were retrieved by the electronic patient record for analysis. STATISTICAL ANALYSIS: Data were analyzed using SPSS version 19. RESULTS: One hundred and one PET/CT scans were performed for patients with elevated CEA. Fifty-eight of these were performed for patients with known primary malignancy and were excluded; 43 PET/CT scans were performed for patients without known primary malignancy and were included. Thirty-three (77%) had a positive PET/CT. Among the 32 patients with malignancy, 15 (47%) suffered from lung cancer and 8 (25%) suffered from colorectal cancer. The sensitivity (97%), specificity (82%), positive predictive value (94%), negative predictive value (90%), and accuracy (93%) were calculated. Thirty (91%) patients had resultant change in management. The mean CEA level for patients with malignancy (46.1 ng/ml) was significantly higher than those without malignancy (3.82 ng/ml) (P < 0.05). In predicting the presence of malignancy, a CEA cutoff at 7.55 ng/ml will achieve a sensitivity of 91% and a specificity of 73%. CONCLUSION: PET/CT, in our study population, appears to be sensitive, specific, and accurate in investigating patients with elevated CEA and without known primary malignancy. In addition to diagnosis of underlying primary malignancy, PET/CT also reveals occult metastases which would affect patient treatment options. Its role in investigating patients with elevated CEA and without known primary, compared with other investigation modalities, remains to be studied.

15.
Biomed Opt Express ; 7(11): 4711-4717, 2016 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-27896010

RESUMEN

There have recently been several studies published involving terahertz (THz) imaging of frozen biomedical samples. In this paper, we investigate the effects of the freeze-thaw cycle on THz properties of porcine muscle and fat samples. For ordinary freezing, there was a significant change in the THz properties after thawing for muscle tissue but not for fat tissue. However, if snap-freezing was combined with fast-thawing instead of ordinary freezing and ordinary thawing, then the freeze-thaw hysteresis was removed.

16.
Ultrasound Med Biol ; 42(8): 2010-6, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27131839

RESUMEN

Ultrasound is useful in assessing cervical lymphadenopathy. Advancement of computer science technology allows accurate and reliable assessment of medical images. The aim of the study described here was to evaluate the diagnostic accuracy of computer-aided assessment of the intranodal vascularity index (VI) in differentiating the various common causes of cervical lymphadenopathy. Power Doppler sonograms of 347 patients (155 with metastasis, 23 with lymphoma, 44 with tuberculous lymphadenitis, 125 reactive) with palpable cervical lymph nodes were reviewed. Ultrasound images of cervical nodes were evaluated, and the intranodal VI was quantified using a customized computer program. The diagnostic accuracy of using the intranodal VI to distinguish different disease groups was evaluated and compared. Metastatic and lymphomatous lymph nodes tend to be more vascular than tuberculous and reactive lymph nodes. The intranodal VI had the highest diagnostic accuracy in distinguishing metastatic and tuberculous nodes with a sensitivity of 80%, specificity of 73%, positive predictive value of 91%, negative predictive value of 51% and overall accuracy of 68% when a cutoff VI of 22% was used. Computer-aided assessment provides an objective and quantitative way to evaluate intranodal vascularity. The intranodal VI is a useful parameter in distinguishing certain causes of cervical lymphadenopathy and is particularly useful in differentiating metastatic and tuberculous lymph nodes. However, it has limited value in distinguishing lymphomatous nodes from metastatic and reactive nodes.


Asunto(s)
Procesamiento de Imagen Asistido por Computador/métodos , Ganglios Linfáticos/irrigación sanguínea , Ganglios Linfáticos/diagnóstico por imagen , Enfermedades Linfáticas/diagnóstico por imagen , Ultrasonografía Doppler/métodos , Diagnóstico Diferencial , Humanos , Metástasis Linfática , Cuello , Curva ROC , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Resistencia Vascular
17.
Spine (Phila Pa 1976) ; 41(13): 1096-1103, 2016 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-26890951

RESUMEN

STUDY DESIGN: Longitudinal follow-up study. OBJECTIVE: This current study aimed to further assess progression, incidence, and risk factors of lumbar spondylolisthesis in these subjects at 4-year follow-up. SUMMARY OF BACKGROUND DATA: A survey for osteoporotic fractures in Hong Kong during 2001 to 2003 represented the first large scale prospective population-based study on bone health in elderly (≥65 years) Chinese men and women. A follow-up study was performed at year-4. METHODS: The lateral lumbar radiographs of 1519 male and 1546 female subjects at year-4 follow-up were analyzed using the Meyerding classification, and compared with the baseline findings. RESULTS: Spondylolisthesis progressed in 13.0%, and de novo spondylolisthesis appeared in 12.4% in men. Spondylolisthesis progressed in 16.5%, and de novo spondylolisthesis appeared in 12.7% in women. In women, higher weight, body mass index, spine and hip bone mineral density (BMD), lower physical activity and lower grip strength were significant factors associated with spondylolisthesis progression, whereas only higher spine BMD was a marginally significant factor associated with spondylolisthesis progression for men. A weak association was noted between spondylolisthesis and lower back pain incidence in women, but not in men. CONCLUSION: Lumbar spondylolisthesis progression in elderly Chinese at 4-year follow-up was characterized by this study. LEVEL OF EVIDENCE: 3.


Asunto(s)
Pueblo Asiatico , Progresión de la Enfermedad , Vértebras Lumbares/diagnóstico por imagen , Vigilancia de la Población , Espondilolistesis/diagnóstico por imagen , Espondilolistesis/epidemiología , Anciano , Anciano de 80 o más Años , Femenino , Estudios de Seguimiento , Hong Kong/epidemiología , Humanos , Masculino , Osteoporosis/diagnóstico por imagen , Osteoporosis/epidemiología , Fracturas Osteoporóticas/diagnóstico por imagen , Fracturas Osteoporóticas/epidemiología , Estudios Prospectivos , Factores de Riesgo
18.
Biomed Res Int ; 2016: 8905916, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26881230

RESUMEN

Cystic change in metastatic lymph nodes of papillary thyroid carcinoma (PTC) is a diagnostic challenge for fine needle aspiration (FNA) because of the scant cellularity. The aim of this study was to evaluate the measurement of thyroglobulin in fine needle aspirate (Tg-FNA) for detecting metastatic PTC in patients with cystic neck lesions and to validate the optimal cutoff value of Tg-FNA. A total of 75 FNA specimens of cystic lesions were identified, including 40 of metastatic PTC. Predetermined threshold levels of 0.04 (minimum detection level), 0.9, 10.0, and 77.0 ng/mL (maximum normal serum-Tg level) were used to evaluate the diagnostic accuracy of Tg-FNA for metastatic PTC detection. The areas under the receiver operating characteristic curve for diagnosing metastatic PTC of Tg-FNA values of 0.04, 0.9, 10.0, and 77.0 ng/mL were 0.5 (95% confidence interval [CI], 0.382-0.618), 0.645 (95% CI, 0.526-0.752), 0.945 (95% CI, 0.866-0.984), and 0.973 (95% CI, 0.907-0.996), respectively. With a cutoff value of 77.0 ng/mL, the combination of Tg-FNA and FNA cytology showed superior diagnostic power (97.5% sensitivity and 100% specificity) compared to FNA cytology alone (80% sensitivity and 100% specificity). We recommend a Tg-FNA cutoff of 77.0 ng/mL, the maximum normal serum-Tg level, for cystic neck lesions.


Asunto(s)
Biopsia con Aguja Fina , Carcinoma/diagnóstico , Citodiagnóstico , Tiroglobulina/aislamiento & purificación , Neoplasias de la Tiroides/diagnóstico , Carcinoma/genética , Carcinoma/patología , Carcinoma Papilar , Humanos , Ganglios Linfáticos/patología , Metástasis Linfática , Tiroglobulina/genética , Cáncer Papilar Tiroideo , Neoplasias de la Tiroides/genética , Neoplasias de la Tiroides/patología
19.
J Neurosurg ; 124(5): 1245-9, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26473778

RESUMEN

OBJECT The objective of this study was to generate data on the local prevalence of unruptured intracranial aneurysms (UIAs) in asymptomatic Hong Kong Chinese individuals. First-degree relatives of patients with aneurysmal subarachnoid hemorrhage (aSAH) were recruited as surrogates of the general population and to explore the potential role of screening in this locality. METHODS The authors identified first-degree relatives of consecutive patients with subarachnoid hemorrhage from a ruptured aneurysm who were admitted to a university hospital in Hong Kong from June 2008 to December 2010. Magnetic resonance angiography (MRA) was the imaging modality used to screen the cerebral vasculature of these asymptomatic individuals. If MRA showed abnormal findings, CT angiography was performed to confirm the MRA findings. RESULTS In total, 7 UIAs were identified from the 305 MR angiograms obtained. The prevalence of UIAs in first-degree relatives of patients with aSAH in the Hong Kong Chinese population was 2.30% (95% CI1.02%-4.76%). This percentage was lower than the prevalence rate of 3.2% from a meta-analysis of the literature. The sizes of the UIAs detected ranged from 1.4 mm to 7.5 mm; 85.7% of the UIAs detected in this study were < 5 mm, in contrast to 66% noted in the literature. One of the UIAs identified underwent endovascular stent placement with a flow diverter. None of the UIAs identified ruptured or became symptomatic during a median follow-up period of 3.5 years. CONCLUSIONS The prevalence of UIAs in first-degree relatives of patients with aSAH in the Hong Kong Chinese population was lower than that in Caucasians. At the same time, most of the UIAs detected in this study were small (85.7% were < 5 mm, vs 66% in a meta-analysis). With a similar incidence of aSAH in Hong Kong (7.5 per 100,000 person-years) as compared with data cited in the literature, the hypothesis that UIA rupture risk size threshold is different in Chinese patients should be further investigated.


Asunto(s)
Pueblo Asiatico/estadística & datos numéricos , Aneurisma Intracraneal/etnología , Aneurisma Intracraneal/epidemiología , Tamizaje Masivo , Adulto , Angiografía Cerebral , Estudios Transversales , Femenino , Humanos , Aneurisma Intracraneal/diagnóstico por imagen , Aneurisma Intracraneal/genética , Angiografía por Resonancia Magnética , Masculino , Persona de Mediana Edad , Hemorragia Subaracnoidea/diagnóstico por imagen , Hemorragia Subaracnoidea/epidemiología , Hemorragia Subaracnoidea/etnología , Hemorragia Subaracnoidea/genética , Tomografía Computarizada por Rayos X
20.
Respirology ; 21(3): 533-40, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26690300

RESUMEN

BACKGROUND AND OBJECTIVE: Mesenteric fat thickness (MFT) was associated with metabolic syndrome (MetS) and obstructive sleep apnoea (OSA) in separate studies. This study aimed to assess whether the association of MFT with MetS was independent of OSA in subjects with suspected OSA. METHODS: Two hundred forty-two subjects (men: 181; women: 61) with suspected OSA underwent ultrasound examinations for measurements of mesenteric, subcutaneous and preperitoneal fat thicknesses after overnight polysomnography. Anthropometric measurements and metabolic risk profile were assessed. RESULTS: Two hundred twenty-one (91%) subjects were confirmed to have OSA with Apnoea-Hypopnoea Index (AHI) >5/h. MFT had significant correlation (P < 0.01) with AHI and most MetS components. In partial correlation with adjustment for AHI, MFT had significant correlation (P < 0.01) with most MetS components including fasting plasma glucose (r = 0.25), triglycerides (r = 0.24), HDL cholesterol (r = -0.29) and waist circumference (r = 0.56). In multivariate logistic regression with adjustments for the confounding variables including AHI, MFT was the only variable independently associated with MetS, with the odds ratio of 5.48 (95% CI: 1.5-20.0) for every 1 cm increase of MFT. When the subjects were subdivided into obese (BMI ≥ 27.5 kg/m(2) ) and non-obese (BMI < 27.5 kg/m(2) ) groups, the positive association of MFT with MetS persisted in the non-obese group only, with the odds ratio of 22 (95% CI 2.8-174.1) for every 1 cm increase of MFT. The AHI had significant association with MetS in male subjects only. CONCLUSION: MFT, rather than AHI, is the major independent determinant of MetS in subjects with suspected OSA, particularly in non-obese subjects. See Editorial, page 408.


Asunto(s)
Grasa Abdominal/diagnóstico por imagen , Síndrome Metabólico/etiología , Obesidad/complicaciones , Apnea Obstructiva del Sueño/etiología , Femenino , Humanos , Masculino , Mesenterio/diagnóstico por imagen , Síndrome Metabólico/diagnóstico por imagen , Persona de Mediana Edad , Obesidad/diagnóstico , Apnea Obstructiva del Sueño/diagnóstico por imagen , Ultrasonografía
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