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1.
BMC Musculoskelet Disord ; 21(1): 433, 2020 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-32620099

RESUMEN

BACKGROUND: Lumbar disc degeneration (LDD) is a condition associated with recurrent low back pain (LBP). Knowledge regarding effective management is limited. As a step towards the identification of risk, prognostic or potentially modifiable factors in LDD patients, the aim of this study was to explore the hypothesis that intrinsic lumbar spine shape is associated with LDD and clinical outcomes in symptomatic adults. METHODS: 3 T MRI was used to acquire T2-weighted sagittal images (L1-S1) from 70 healthy controls and LDD patients (mean age 49 years, SD 11, range 31-71 years). Statistical Shape Modelling (SSM) was used to describe lumbar spine shape. SSM identified variations in lumbar shape as 'modes' of variation and quantified deviation from the mean. Intrinsic shape differences were determined between LDD groups using analysis of variance with post-hoc comparisons. The relationship between intrinsic shape and self-reported function, mental health and quality of life were also examined. RESULTS: The first 7 modes of variation explained 91% of variance in lumbar shape. Higher LDD sum scores correlated with a larger lumbar lordosis (Mode 1 (55% variance), P = 0.02), even lumbar curve distribution (Mode 2 (12% variance), P = 0.05), larger anterior-posterior (A-P) vertebral diameter (Mode 3 (10% variance), P = 0.007) and smaller L4-S1 disc spaces (Mode 7 (2% variance), P ≤ 0.001). In the presence of recurrent LBP, LDD was associated with a larger A-P vertebral diameter (Mode 3) and a more even lumbar curvature with smaller L5/S1 disc spaces (Mode 4), which was significantly associated with patient quality of life (P = 0.002-0.04, rp = 0.43-0.61)). CONCLUSIONS: This exploratory study provides new evidence that intrinsic shape phenotypes are associated with LDD and quality of life in patients. Longitudinal studies are required to establish the potential role of these risk or prognostic shape phenotypes.


Asunto(s)
Degeneración del Disco Intervertebral/patología , Disco Intervertebral/patología , Lordosis/patología , Vértebras Lumbares/patología , Imagen por Resonancia Magnética , Adulto , Anciano , Femenino , Humanos , Disco Intervertebral/diagnóstico por imagen , Degeneración del Disco Intervertebral/complicaciones , Lordosis/diagnóstico por imagen , Dolor de la Región Lumbar/etiología , Dolor de la Región Lumbar/patología , Vértebras Lumbares/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Modelos Estadísticos , Calidad de Vida
2.
Dig Liver Dis ; 56(3): 484-494, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37968144

RESUMEN

BACKGROUND: Most ultrasound-based methods for assessing liver fibrosis still need further validation with liver biopsy used as gold standard to assess their accuracy. AIMS: To assess accuracy of three shear wave elastography (SWE) methods: 1) Philips Elast Point Quantification (ElastPQTM), 2) Siemens Virtual TouchTM Quantification (VTQ) acoustic radiation force impulse (ARFI), and 3) transient elastography (TE) measured by Echosens FibroscanTM. METHODS: 160 patients underwent liver stiffness measurements (LSM) with three SWE methods immediately prior to liver biopsy. RESULTS: The number of LSM required for reliable studies could be reduced to 6 for ElastPQ and to 7 for VTQ from standard recommendations of 10. Significant fibrosis and interquartile range/median (IQR/M)> 30 were independent predictors for lower reliability for detection of liver fibrosis. Ordinal logistic regression corrected for age showed that there was a significant interaction between steatosis (p = 0.008) and lobular inflammation (p = 0.04) and VTQ (ARFI) and between lobular inflammation and TE (p = 0.006). CONCLUSIONS: We showed variations in SWE measurements using different ARFI technologies. TE and ElastPQ achieved good diagnostic performance, whereas VTQ showed lower diagnostic accuracy. The number of measurements required for reliable studies can be reduced to 6 for ElastPQ and to 7 for VTQ, which have important clinical implications.


Asunto(s)
Diagnóstico por Imagen de Elasticidad , Hepatopatías , Humanos , Diagnóstico por Imagen de Elasticidad/métodos , Reproducibilidad de los Resultados , Hepatopatías/diagnóstico , Hígado/diagnóstico por imagen , Hígado/patología , Cirrosis Hepática/diagnóstico por imagen , Cirrosis Hepática/patología , Biopsia , Inflamación/patología
3.
Hepat Med ; 15: 51-61, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37325088

RESUMEN

Purpose: The Controlled Attenuation Parameter (CAP score) is based on ultrasonic properties of retropropagated radiofrequency signals acquired by FibroscanTM (Echosens, Paris, France). Since ultrasound propagation is influenced by the presence of fat, CAP score was developed to quantify steatosis. The aim of this study was to delineate the accuracy of CAP in diagnosing hepatic steatosis, compared to the gold standard of liver biopsy. Patients and Methods: A total of 150 patients underwent same-day liver biopsy and measurement of hepatic steatosis with Fibroscan. Only examinations with 10 satisfactory measurements, and an inter-quartile range of less than 30% of the median liver stiffness values were included for data analysis. Histological staging was then correlated with median values and Spearman correlation calculated. P values of <0.05 were considered statistically significant. Results: For diagnosis of hepatic steatosis (HS), CAP could predict the steatosis S2 with AUROC 0.815 (95% CI 0.741-0.889), sensitivity (0.81) and specificity (0.73) when the optimal cut-off value was set at 288 dB/m. CAP detected histological grade S3 with AUROC 0.735 (95% CI 0.618-0.851), sensitivity (0.71) and specificity (0.74), with a cut-off value of 330 dB/m. The AUROC for steatosis grade S1 was 0.741 (95% CI 0.650-0.824), with a cut-off value of 263 dB/m with sensitivity 0.75 and specificity 0.70. Univariate analysis showed a correlation between CAP and diabetes (p 0.048). Conclusion: The performance of CAP to diagnose steatosis severity decreases as steatosis progresses. CAP is associated with diabetes but not other clinical factors and parameters of the metabolic syndrome.

4.
Insights Imaging ; 14(1): 202, 2023 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-38001262

RESUMEN

Ultrasound practice is a longstanding tradition for radiology departments, being part of the family of imaging techniques. Ultrasound is widely practiced by non-radiologists but becoming less popular within radiology. The position of ultrasound in radiology is reviewed, and a possible long-term solution to manage radiologist expectations is proposed. An international group of experts in the practice of ultrasound was invited to describe the current organisation of ultrasound within the radiology departments in their own countries and comment on the interaction with non-radiologists and training arrangements. Issues related to regulation, non-medical practitioners, and training principles are detailed. A consensus view was sought from the experts regarding the position of ultrasound within radiology, with the vision of the best scenario for the continuing dominance of radiologists practising ultrasound. Comments were collated from nine different countries. Variable levels of training, practice, and interaction with non-radiologist were reported, with some countries relying on non-physician input to manage the service. All experts recognised there was a diminished desire to practice ultrasound by radiologists. Models varied from practising solely ultrasound and no other imaging techniques to radiology departments being central to the practice of ultrasound by radiologists and non-radiologist, housed within radiology. The consensus view was that the model favoured in select hospitals in Germany would be the most likely setup for ultrasound radiologist to develop and maintain practice. The vision for 20 years hence is for a central ultrasound section within radiology, headed by a trained expert radiologist, with non-radiologist using the facilities.Critical relevance statement The future of ultrasound within the radiology department should encompass all ultrasound users, with radiologists expert in ultrasound, managing the ultrasound section within the radiology department. The current radiology trainees must learn of the importance of ultrasound as a component of the 'holistic' imaging of the patient.Key points: 1. Ultrasound imaging within radiology departments precedes the introduction of CT and MR imaging and was first used over 50 years ago.2. Non-radiology practitioners deploy ultrasound examinations to either 'problem solve' or perform a comprehensive ultrasound examination; radiologists provide comprehensive examinations or use ultrasound to direct interventional procedures.3. Radiology does not 'own' ultrasound, but radiologists are best placed to offer a comprehensive patient-focused imaging assessment.4. A vision of the future of ultrasound within the radiology department is encompassing all ultrasound users under radiologists who are experts in ultrasound, positioned within the radiology department.5. The current radiology trainee must be aware of the importance of ultrasound as a component of the 'holistic' imaging of the patient.

5.
J Reprod Med ; 57(7-8): 319-24, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22838248

RESUMEN

OBJECTIVE: To review the indications, efficacy and follow-up for gestational trophoblastic tumor (GTT) patients treated for uterine arteriovenous vascular malformations (AVMs) and bleeding vaginal metastases with modern polyvinyl alcohol particle (PVA)-based radiological embolization. STUDY DESIGN: GTT patients undergoing embolization were identified from the Charing Cross Hospital database. The patients' records were assessed for indication, technique used, primary and overall success in controlling bleeding, complications and subsequent pregnancy outcome. RESULTS: During the period 2000-2009, 19 patients were treated for persistent or life-threatening bleeding by PVA-based uterine artery embolization performed via the femoral artery approach. Embolization resulted in control of hemorrhage in 18 of the 19 patients; 15 achieved control after the first procedure, with only 4 patients requiring a second procedure. In 1 case surgical intervention was required to control bleeding. The most frequent morbidity from the procedure was pelvic pain, requiring opiate administration; there were no other regular complications. The fertility outcome for these 19 patients indicates that 9 women have gone on to deliver a total of 12 healthy infants postembolization. CONCLUSION: For GTT patients with heavy bleeding from AVMs, uterine artery embolization is a safe and effective treatment with low short-term toxicity and no obvious detrimental effect on future fertility.


Asunto(s)
Malformaciones Arteriovenosas/terapia , Enfermedad Trofoblástica Gestacional/complicaciones , Embolización de la Arteria Uterina , Hemorragia Uterina/terapia , Neoplasias Uterinas/complicaciones , Adulto , Malformaciones Arteriovenosas/etiología , Femenino , Enfermedad Trofoblástica Gestacional/terapia , Humanos , Dolor Pélvico/etiología , Alcohol Polivinílico , Embarazo , Índice de Embarazo , Radiografía Intervencional , Hemorragia Uterina/etiología , Neoplasias Uterinas/terapia , Adulto Joven
6.
Gait Posture ; 94: 222-229, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-33980472

RESUMEN

BACKGROUND: Lumbar Disc Degeneration (LDD) is associated with recurrent low back pain (LBP) (symptomatic). However, in some instances of LDD, people do not experience LBP (asymptomatic). RESEARCH QUESTION: As a step towards understanding why some people with LDD experience LBP and others do not, the primary aim of this study was to examine differences in anticipatory (APA) and compensatory postural adjustments (CPA), between symptomatic LDD patients (LDD pain) and asymptomatic LDD controls (LDD no pain) during postural perturbation. The secondary aim was to determine simultaneous differences in mental health, disability and quality of life status. METHODS: 3 T MRI was used to acquire T2 weighted images (L1-S1) from LDD no pain (n = 34) and LDD pain groups (n = 34). In this observational study, responses to predicted and unpredicted forward perturbations were examined using three dimensional motion capture. A Mann Whitney U test was conducted to examine group differences in sagittal spine and lower limb kinematics (integrated angular displacements during four established APA and CPA time intervals), anxiety, depression, disability and quality of life. RESULTS: The LDD pain group exhibited lower hip and knee displacements (p = 0.049-0.040) than the LDD no pain group during predicted and unpredicted perturbation. The LDD pain group also exhibited higher compensatory lumbar displacement than the LDD no pain group (p = 0.040-0.005) in the predicted condition but there was no difference observed in the unpredicted condition. The LDD pain group experienced higher levels of depression, anxiety and disability (p < 0.0001) and lower quality of life (p = 0.0001) than LDD controls. SIGNIFICANCE: Symptomatic LDD patients are different from LDD controls; they exhibit different kinematic strategies, levels of disability, anxiety, depression and quality of life. Effective care may benefit from evaluating and targeting these differences.


Asunto(s)
Degeneración del Disco Intervertebral , Dolor de la Región Lumbar , Fenómenos Biomecánicos , Humanos , Dolor de la Región Lumbar/complicaciones , Vértebras Lumbares , Calidad de Vida
7.
Radiographics ; 31(5): 1307-19, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21918046

RESUMEN

Muscle-sparing perforator free flap breast reconstruction with the use of an inferior epigastric or gluteal perforating artery to create a vascular pedicle is increasingly popular because it obviates breast implants and results in lower donor site morbidity than breast reconstruction with myocutaneous flaps. The tissue harvesting procedure for a perforator free flap involves dissecting the subcutaneous fat of the anterior abdominal wall or the buttock to locate and visually evaluate the perforating arteries so as to decide which one is most suitable for the vascular pedicle. The vessel selected depends on multiple anatomic and surgical considerations, and the decision-making process can be exceptionally time-consuming, in part because of the wide variation that occurs in vascular anatomy. Preoperative imaging can greatly improve the efficiency of the selection process. Doppler ultrasonography (US) is the most frequently used modality for vascular mapping, but the results are mixed because most perforating arteries have a diameter of less than 15 mm, the threshold for reliable visualization with US. A computed tomographic (CT) angiographic evaluation performed with the use of specific postprocessing and display techniques may be more accurate for identifying the most suitable vessel. CT angiography provides valuable information that can help optimize surgical planning, decrease time spent in the operating room, and improve the outcome of breast reconstruction surgery.


Asunto(s)
Angiografía/métodos , Arterias Epigástricas/diagnóstico por imagen , Arteria Ilíaca/diagnóstico por imagen , Mamoplastia/métodos , Cuidados Preoperatorios , Recto del Abdomen/irrigación sanguínea , Colgajos Quirúrgicos/irrigación sanguínea , Tomografía Computarizada por Rayos X/métodos , Procedimientos Quirúrgicos Vasculares/métodos , Anastomosis Quirúrgica , Nalgas/irrigación sanguínea , Arterias Epigástricas/cirugía , Femenino , Humanos , Arteria Ilíaca/cirugía , Arterias Mamarias/cirugía , Cintigrafía , Recto del Abdomen/cirugía
8.
PLoS One ; 16(4): e0249308, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33793605

RESUMEN

People with chronic low back pain (LBP) exhibit changes in postural control. Stereotypical muscle activations resulting from external perturbations include anticipatory (APAs) and compensatory (CPAs) postural adjustments. The aim and objective of this study was to determine differences in postural control strategies (peak amplitude, APAs and CPAs) between symptomatic and asymptomatic adults with and without Lumbar Disc Degeneration (LDD) using surface electromyography during forward postural perturbation. Ninety-seven subjects participated in the study (mean age 50 years (SD 12)). 3T MRI was used to acquire T2 weighted images (L1-S1). LDD was determined using Pfirrmann grading. A bespoke translational platform was designed to deliver horizontal perturbations in sagittal and frontal planes. Electromyographic activity was analysed bilaterally from 8 trunk and lower limb muscles during four established APA and CPA epochs. A Kruskal-Wallis H test with Bonferroni correction for multiple comparisons was conducted. Four groups were identified: no LDD no pain (n = 19), LDD no pain (n = 38), LDD pain (n = 35) and no LDD pain (n = 5). There were no significant differences in age or gender between groups. The most significant difference between groups was observed during forward perturbation. In the APA and CPA phases of predictable forward perturbation there were significant differences ankle strategy between groups (p = 0.007-0.008); lateral gastrocnemius and tibialis anterior activity was higher in the LDD pain than the LDD no pain group. There were no significant differences in the unpredictable condition (p>0.05). These findings were different from the remaining groups, where significant differences in hip strategy were observed during both perturbation conditions (p = 0.004-0.006). Symptomatic LDD patients exhibit different electromyographic strategies to asymptomatic LDD controls. Future LBP electromyographic research should benefit from considering assessment of both lower limbs in addition to the spine. This approach could prevent underestimation of postural control deficits and guide targeted rehabilitation.


Asunto(s)
Electromiografía , Degeneración del Disco Intervertebral/fisiopatología , Dolor de la Región Lumbar/fisiopatología , Equilibrio Postural/fisiología , Adulto , Estudios Transversales , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Recto del Abdomen/fisiología
9.
Integr Med (Encinitas) ; 19(3): 30-34, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33132775

RESUMEN

BACKGROUND: There have been isolated reports of Aloe vera hepatotoxicity, usually manifested by transient liver function test abnormalities. While the European Food Safety Authority has recommended that whole leaf products containing the rind of the Aloe vera plant should not be used for human oral consumption, those Aloe vera gels made of the treated plant pulp alone are considered safe for daily consumption, provided recommended quantities are not exceeded. We aimed to assess hepatic function in healthy volunteers consuming the purified plant pulp Aloe vera gel over a 60 day period. METHODS: 35 healthy volunteers consumed the maximum recommended daily dose of 2 oz (57 mL) of Aloe vera gel twice daily for a total of 60 days. The participants attended an initial baseline visit where biochemical measurements of hepatic synthetic function were obtained, and each volunteer underwent hepatic ultrasound with elastography, superb microvascular imaging and image quantification. Further visits were undertaken at days 30 and 60 to undergo the same biochemical and imaging measurements of liver function to monitor if there were any changes in the parameters measured. RESULTS: Seven volunteers failed to complete the study, citing unspecified gastrointestinal upset and/or an inability to tolerate the taste of the Aloe vera gel. None of these individuals had disturbance of biochemical or imaging parameters of hepatic function. Of the remaining 27 healthy volunteers, none had a change in either biochemical indices of liver function, or of ultrasound markers of hepatic blood flow or liver tissue elasticity after 60 days of Aloe vera gel consumption. However, there was a non-significant reduction in serum homocysteine levels as the only detectable change in the cohort. CONCLUSIONS: Despite reports of potential hepatotoxicity with some Aloe vera products, in this healthy cohort, extended consumption of purified plant-pulp Aloe vera gel did not have any detectable effects on hepatic function, blood flow or tissue elasticity.

10.
J Reprod Med ; 53(8): 575-8, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18773620

RESUMEN

OBJECTIVE: To assess the accuracy of Doppler ultrasound (DU) compared with magnetic resonance imaging (MRI) in high-risk patients with gestational trophoblastic neoplasia (GTN). STUDY DESIGN: From January 2005 to October 2007, patients with proven high-risk GTN or suspicion of relapse who had both DU and MRI of the pelvis were reviewed retrospectively for tumor detection and tumor extent and vascularity. RESULTS: There were a total of 54 patients who had both DU and MRI performed; of these, 40 were first-time presentation and 14 had either residual disease not responding to chemotherapy or suspicion of recurrent GTN based on rising human chorionic gonadotropin (hCG). Extrauterine extension and extent of endometrial encroachment were better assessed on MRI than on DU in 10 of 46 patients with visible uterine lesion. CONCLUSION: MRI and DU are complementary investigations of the pelvis in patients with GTN. Tumor vascularity is better assessed on DU, tumor extension and detection are better with MRI.


Asunto(s)
Enfermedad Trofoblástica Gestacional/diagnóstico , Enfermedad Trofoblástica Gestacional/patología , Imagen por Resonancia Magnética , Neoplasias Pélvicas/diagnóstico , Neoplasias Pélvicas/patología , Ultrasonografía Prenatal , Estudios de Cohortes , Femenino , Humanos , Embarazo , Ultrasonografía Doppler
11.
AJR Am J Roentgenol ; 189(4): 819-23, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17885051

RESUMEN

OBJECTIVE: An increase in the ratio of phosphomonoester (PME) to phosphodiester (PDE) during 31P MR spectroscopy of the liver has been observed with increasing severity of hepatitis C-related liver disease. The purpose of this study was to investigate the utility of 31P MR spectroscopy as a biomarker of response to interferon and ribavirin treatment. SUBJECTS AND METHODS: Forty-seven patients with biopsy-proven hepatitis C undergoing viral eradication treatment with interferon and ribavirin underwent hepatic 31P MR spectroscopy at 1.5 T (voxel size, 70 x 70 x 70 mm; TR, 10,000; number of signals averaged, 48). All underwent baseline imaging before treatment and repeated imaging at 6-month intervals after the start of treatment. RESULTS: All patients underwent follow-up imaging 6 months after the start of treatment; 25 patients, 12 months; and 10 patients, 18 months after the start of treatment. According to the Ishak histologic scoring system, nine patients had mild hepatitis; 30 patients, moderate to severe hepatitis; and eight patients, cirrhosis. Thirty-two patients responded to antiviral treatment. Among these patients, 25 had a decrease in PME/PDE ratio on follow-up imaging. Among responders the mean baseline PME/PDE ratio decreased from 0.27 +/- 0.02 (standard error) to 0.16 +/- 0.01 after treatment (paired Student's t test, p < 0.001). Among the 15 virologic nonresponders, the ratios were similar in six patients; six other patients had an increase on follow-up imaging. In the latter nonresponder group, the mean baseline PME/PDE ratio was 0.21 +/- 0.03 compared with 0.31 +/- 0.08 after treatment (paired Student's t test, p =0.24). CONCLUSION: The in vivo hepatic PME/PDE ratio decreased in patients with hepatitis C who responded to antiviral treatment and remained similar or increased in patients without a virologic response. These results suggest that PME and PDE can be used as biomarkers in a noninvasive test of response to treatment.


Asunto(s)
Hepatitis C Crónica/diagnóstico , Hepatitis C Crónica/tratamiento farmacológico , Espectroscopía de Resonancia Magnética/métodos , Compuestos de Fósforo/análisis , Vacunas contra Hepatitis Viral/uso terapéutico , Adulto , Anciano , Femenino , Hepatitis C Crónica/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Isótopos de Fósforo , Resultado del Tratamiento
12.
World J Gastroenterol ; 12(22): 3461-5, 2006 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-16773702

RESUMEN

Patients who are chronically infected with the hepatitis C virus often develop chronic liver disease and assessment of the severity of liver injury is required prior to considering viral eradication therapy. This article examines the various assessment methods currently available from gold standard liver biopsy to serological markers and imaging. Ultrasound is one of the most widely used imaging modalities in clinical practice and is already a first-line diagnostic tool for liver disease. Microbubble ultrasound contrast agents allow higher resolution images to be obtained and functional assessments of microvascular change to be carried out. The role of these agents in quantifying the state of hepatic injury is discussed as a viable method of determining the stage and grade of liver disease in patients with hepatitis C. Although currently confined to specialist centres, the availability of microbubble contrast-enhanced ultrasound will inevitably increase in the clinical setting.


Asunto(s)
Hepatitis C Crónica/complicaciones , Hepatitis C Crónica/diagnóstico por imagen , Hepatopatías/diagnóstico por imagen , Hepatopatías/etiología , Microburbujas , Ultrasonografía/métodos , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Hígado/diagnóstico por imagen , Hígado/patología , Masculino , Persona de Mediana Edad , Sensibilidad y Especificidad , Índice de Severidad de la Enfermedad
13.
Ultrasound Med Biol ; 41(7): 1938-47, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25935597

RESUMEN

Non-linear propagation of ultrasound creates artifacts in contrast-enhanced ultrasound images that significantly affect both qualitative and quantitative assessments of tissue perfusion. This article describes the development and evaluation of a new algorithm to correct for this artifact. The correction is a post-processing method that estimates and removes non-linear artifact in the contrast-specific image using the simultaneously acquired B-mode image data. The method is evaluated on carotid artery flow phantoms with large and small vessels containing microbubbles of various concentrations at different acoustic pressures. The algorithm significantly reduces non-linear artifacts while maintaining the contrast signal from bubbles to increase the contrast-to-tissue ratio by up to 11 dB. Contrast signal from a small vessel 600 µm in diameter buried in tissue artifacts before correction was recovered after the correction.


Asunto(s)
Artefactos , Velocidad del Flujo Sanguíneo/fisiología , Arterias Carótidas/diagnóstico por imagen , Arterias Carótidas/fisiología , Aumento de la Imagen/métodos , Ultrasonografía/métodos , Medios de Contraste , Humanos , Interpretación de Imagen Asistida por Computador/métodos , Dinámicas no Lineales , Fantasmas de Imagen , Fosfolípidos , Reproducibilidad de los Resultados , Dispersión de Radiación , Sensibilidad y Especificidad , Hexafluoruro de Azufre , Ondas Ultrasónicas , Ultrasonografía/instrumentación
14.
Arthritis ; 2015: 852989, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25785197

RESUMEN

Objectives. Early change in rheumatoid arthritis (RA) is characterised by periarticular osteopenia. We investigated the relationship of early metacarpal digital X-ray radiogrammetry bone mineral density (DXR-BMD) change rate (RC-BMD, mg/cm(2)/month) to longitudinal changes in hand and feet radiographic and wrist MRI scores over 1 year. Materials and Methods. 10 RA patients completed the study and had wrist 3T-MRI and hand and feet X-rays at various time points over 1 year. MRI was scored by RAMRIS, X-ray was done by van der Heijde modified Sharp scoring, and RC-BMD was analysed using dxr-online. Results. There was good correlation amongst the two scorers for MRI measures and ICC for erosions: 0.984, BME: 0.943, and synovitis: 0.657. Strong relationships were observed between RC-BMD at 12-week and 1-year change in wrist marrow oedema (BME) (r = 0.78, P = 0.035) but not with erosion, synovitis, or radiographic scores. Conclusion. Early RC-BMD correlates with 1-year wrist BME change, which is a known predictor of future erosion and joint damage. However, in our pilot study, early RC-BMD did not show relationships to MRI erosion or radiographic changes over 1 year. This may reflect a slower kinetic in the appearance of MRI/radiographic erosions, generating the hypothesis that RC-BMD may be a more sensitive and early structural prognostic marker in RA follow-up.

15.
Eur J Radiol ; 82(8): 1286-91, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23562303

RESUMEN

RATIONAL AND OBJECTIVE: Dynamic contrast enhanced (DCE)-MRI has great potential to provide quantitative measure of inflammatory activity in rheumatoid arthritis. There is no current benchmark to establish the stability of signal in the joints of healthy subjects when imaged with DCE-MRI longitudinally, which is crucial so as to differentiate changes induced by treatment from the inherent variability of perfusion measures. The objective of this study was to test a pixel-by-pixel parametric map based approach for analysis of DCE-MRI (Dynamika) and to investigate the variability in signal characteristics over time in healthy controls using longitudinally acquired images. MATERIALS AND METHODS: 10 healthy volunteers enrolled, dominant wrists were imaged with contrast enhanced 3T MRI at baseline, week 12, 24 and 52 and scored with RAMRIS, DCE-MRI was analysed using a novel quantification parametric map based approach. Radiographs were obtained at baseline and week 52 and scored using modified Sharp van der Heidje method. RAMRIS scores and dynamic MRI measures were correlated. RESULTS: No erosions were seen on radiographs, whereas MRI showed erosion-like changes, low grade bone marrow oedema and low-moderate synovial enhancement. The DCE-MRI parameters were stable (baseline scores, variability) (mean±st.dev); in whole wrist analysis, MEmean (1.3±0.07, -0.08±0.1 at week 24) and IREmean (0.008±0.004, -0.002±0.005 at week 12 and 24). In the rough wrist ROI, MEmean (1.2±0.07, 0.04±0.02 at week 52) and IREmean (0.001±0.0008, 0.0006±0.0009 at week 52) and precise wrist ROI, MEmean (1.2±0.09, 0.04±0.04 at week 52) and IREmean (0.001±0.0008, 0.0008±0.001 at week 24 and 52). The Dynamic parameters obtained using fully automated analysis demonstrated strong, statistically significant correlations with RAMRIS synovitis scores. CONCLUSION: The study demonstrated that contrast enhancement does occur in healthy volunteers but the inherent variability of perfusion measures obtained with quantitative DCE-MRI method is low and stable, suggesting its suitability for longitudinal studies of inflammatory arthritis. These results also provide important information regarding potential cut-off levels for imaging remission goals in patients with RA using both RAMRIS and DCE-MRI extracted parametric parameters.


Asunto(s)
Algoritmos , Gadolinio DTPA , Interpretación de Imagen Asistida por Computador/métodos , Imagen por Resonancia Magnética/métodos , Reconocimiento de Normas Patrones Automatizadas/métodos , Articulación de la Muñeca/anatomía & histología , Adulto , Medios de Contraste , Femenino , Voluntarios Sanos , Humanos , Aumento de la Imagen/métodos , Estudios Longitudinales , Masculino , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Adulto Joven
16.
Expert Rev Gastroenterol Hepatol ; 5(1): 91-104, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21309675

RESUMEN

Liver disease is an increasing cause of morbidity and mortality worldwide. Currently, the gold standard for diagnosis and assessment of parenchymal disease is histopathological assessment of a percutaneous or transjugular liver biopsy. The risks and limitations of this technique are well recognized and as a result, significant effort has gone into the development of novel noninvasive methods of diagnosis and longitudinal assessment. Imaging techniques have improved significantly over the past decade and new technologies are beginning to enter clinical practice. Ultrasound, computed tomography and MRI are the main modalities currently used, but novel MRI-based techniques will have an increasing role. While there has been extensive research into the imaging of focal liver disease, the evidence base for imaging in diffuse disease has also undergone recent rapid development, particularly in the assessment of fibrosis and steatosis. Both of these abnormalities of the parenchyma can lead to cirrhosis and/or hepatocellular carcinoma and represent an important opportunity for detection of early liver disease. We discuss the recent advances in liver imaging techniques and their role in the diagnosis and monitoring of diffuse liver disease, with a focus on their current and potential clinical relevance and whether they may replace or augment liver biopsy. We also discuss techniques currently under development and their potential clinical applications in the future.


Asunto(s)
Diagnóstico por Imagen/tendencias , Hígado Graso/patología , Cirrosis Hepática/patología , Biopsia , Hígado Graso/diagnóstico por imagen , Humanos , Cirrosis Hepática/diagnóstico por imagen , Imagen por Resonancia Magnética/tendencias , Espectroscopía de Resonancia Magnética , Tomografía Computarizada por Rayos X/tendencias , Ultrasonografía/tendencias
17.
Eur J Gastroenterol Hepatol ; 22(3): 257-63, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19177027

RESUMEN

AIM: To assess the clinical feasibility of utilizing the presence of perihepatic lymphadenopathy, seen on ultrasound, as a marker of response to antiviral treatment in patients with hepatitis C virus (HCV)-related liver disease. METHODS: Eighty-five patients with HCV-related liver disease [51 men and 34 women; mean age 47 years (range 26-67)] underwent liver biopsy and baseline ultrasound scans. Twenty-two of these patients were followed up longitudinally with 6-monthly ultrasound scans, whereas they were receiving anti-HCV eradication therapy with interferon and ribavirin. Perihepatic lymph nodes detected in the coeliac axis and peripancreatic region were noted, with the largest node size on maximal diameter recorded. The patients were subsequently assessed in the light of long-term virological response to treatment. RESULTS: Perihepatic lymph nodes were detected in 26 of the 85 patients. Of the 22 patients followed up longitudinally, 11 responded to antiviral treatment, nine failed to respond and two did not complete a course of treatment. No significant difference was found between patients with detectable lymphadenopathy and those without according to age, sex, disease severity and genotype. There was a general reduction in size of lymph nodes in both responders and nonresponders to treatment, although this reduction was only significant in the responder group (P=0.003). CONCLUSION: The presence of perihepatic lymphadenopathy when detected in patients with viral hepatitis can potentially serve as an indicator of response to treatment. However, as only 30-40% of patients have detectable lymphadenopathy, its clinical utility is limited.


Asunto(s)
Antivirales/uso terapéutico , Monitoreo de Drogas/métodos , Hepatitis C/tratamiento farmacológico , Hígado/efectos de los fármacos , Ganglios Linfáticos/efectos de los fármacos , Enfermedades Linfáticas/tratamiento farmacológico , Adulto , Anciano , Biopsia , Quimioterapia Combinada , Estudios de Factibilidad , Femenino , Hepacivirus/genética , Hepatitis C/complicaciones , Hepatitis C/diagnóstico , Hepatitis C/diagnóstico por imagen , Hepatitis C/patología , Humanos , Interferones/uso terapéutico , Hígado/patología , Hígado/virología , Ganglios Linfáticos/diagnóstico por imagen , Ganglios Linfáticos/virología , Enfermedades Linfáticas/diagnóstico por imagen , Enfermedades Linfáticas/virología , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Prospectivos , ARN Viral/sangre , Ribavirina/uso terapéutico , Factores de Tiempo , Resultado del Tratamiento , Ultrasonografía , Carga Viral
18.
World J Gastroenterol ; 15(11): 1289-300, 2009 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-19294758

RESUMEN

Improvements in imaging technology allow exploitation of the dual blood supply of the liver to aid in the identification and characterisation of both malignant and benign liver lesions. Imaging techniques available include contrast enhanced ultrasound, computed tomography and magnetic resonance imaging. This review discusses the application of several imaging techniques in the diagnosis and staging of both hepatocellular carcinoma and cholangiocarcinoma and outlines certain characteristics of benign liver lesions. The advantages of each imaging technique are highlighted, while underscoring the potential pitfalls and limitations of each imaging modality.


Asunto(s)
Colangiocarcinoma/patología , Neoplasias Hepáticas/patología , Colangiocarcinoma/diagnóstico por imagen , Medios de Contraste , Hepatocitos/diagnóstico por imagen , Hepatocitos/patología , Humanos , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/secundario , Imagen por Resonancia Magnética , Metástasis de la Neoplasia/diagnóstico por imagen , Metástasis de la Neoplasia/patología , Tomografía Computarizada por Rayos X/métodos , Ultrasonografía/efectos adversos , Ultrasonografía/métodos
19.
Radiology ; 240(1): 130-5, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16720867

RESUMEN

PURPOSE: To prospectively compare transit times of Levovist and SonoVue in healthy volunteers and patients with biopsy-proved hepatitis C-related liver disease. MATERIALS AND METHODS: Institutional review board approval and informed consent were obtained. Forty patients and 25 healthy volunteers were examined. Subjects fasted, a bolus of SonoVue (0.6 mL) was injected into a cubital fossa vein, and hepatic venous time-intensity profiles were measured with spectral Doppler tracing. This was repeated with two injections of Levovist (2 g) and another injection of SonoVue. Time-intensity curves of spectral Doppler signals of right and middle hepatic veins were analyzed. A sustained signal intensity increase of 10% above baseline levels indicated hepatic vein transit time (HVTT). Carotid artery audio intensity was measured in volunteers. Analysis of variance and t tests were used for statistical analysis. RESULTS: Twelve patients had mild hepatitis; 18, moderate or severe hepatitis; and 10, cirrhosis. Mean HVTTs in control, mild hepatitis, moderate or severe hepatitis, and cirrhosis groups were 38.3 seconds +/- 2.4 (standard error), 47.5 seconds +/- 6.5, 29.5 seconds +/- 10.8, and 17.6 seconds +/- 5.0, respectively, with Levovist (P < .001) and 29.4 seconds +/- 6.9, 27.4 seconds +/- 9.3, 22.9 seconds +/- 4.7, and 16.4 seconds +/- 4.9, respectively, with SonoVue (P < .001). HVTT decreased as severity increased at imaging with both contrast agents. There was no significant difference in HVTT between mild and moderate hepatitis groups with SonoVue; however, there were significant differences in HVTT between all patient groups with Levovist. HVTT of SonoVue was shorter than that of Levovist in all groups (P < .001) except the cirrhosis group; in this group, HVTT of the two contrast agents was similar (P = .05). No difference was observed in mean cardiopulmonary transit time for SonoVue or Levovist (9.1 seconds +/- 2.4 [standard error] and 8.4 seconds +/- 2.5, respectively, P = .18). CONCLUSION: HVTT was significantly shorter with SonoVue than with Levovist; there was no significant difference in cardiopulmonary transit time.


Asunto(s)
Medios de Contraste/farmacocinética , Venas Hepáticas/diagnóstico por imagen , Hepatitis C/diagnóstico por imagen , Fosfolípidos/farmacocinética , Polisacáridos/farmacocinética , Hexafluoruro de Azufre/farmacocinética , Femenino , Hepatitis C/clasificación , Humanos , Masculino , Microburbujas , Persona de Mediana Edad , Valores de Referencia , Ultrasonografía Doppler
20.
AJR Am J Roentgenol ; 184(6): 1848-53, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15908541

RESUMEN

OBJECTIVE: Many authors have claimed that Doppler sonography indexes are of value in grading and assessing diffuse liver disease. However, there is much controversy regarding the reliability and reproducibility of these techniques. We performed a prospective study to evaluate whether these methods can grade disease in a well-stratified cohort of patients with hepatitis C virus (HCV)-related liver disease. SUBJECTS AND METHODS: Sixty-five patients with biopsy-proven HCV-related liver disease were recruited, and Doppler sonography was performed by one operator. The patients were classified into one of the following three groups on the basis of the Ishak-modified histologic activity index (HAI) fibrosis (F) and necroinflammatory (NI) scores: mild hepatitis (F < or = 2 and NI < or = 3), moderate or severe hepatitis (3 < or = F < 6 or NI > or = 4), or cirrhosis (F = 6/6). We measured the following Doppler indexes: main hepatic artery peak velocity (Vmax) and resistive index, main portal vein peak velocity (Vmax), and maximal portal vein diameter and circumference that allowed calculation of the portal vein congestive index (portal vein area and portal vein velocity). The ratio of the hepatic artery velocity (Vmax) to the portal vein velocity (Vmax) was also calculated, and the phasicity (triphasic, biphasic, or monophasic) of the hepatic veins of each patient was recorded. We also measured the maximal spleen length longitudinally. RESULTS: A total of 65 patients with liver disease (mild hepatitis, n = 20; moderate or severe hepatitis, n = 25; cirrhosis, n = 20) with biopsy-proven HCV-related liver disease were studied. Optimal hepatic arterial traces were obtained in only 30 patients and portal vein circumference in 18 patients. No significant differences were observed in the Doppler indexes with increasing severity of liver disease. Five (29%) of 17 patients with mild hepatitis had an abnormal hepatic vein trace (i.e., biphasic or monophasic) compared with 11 (55%) of 20 patients with moderate or severe hepatitis and 12 (60%) of 20 patients with cirrhosis. The only index to show a significant intergroup difference was splenic length (analysis of variance, p < 0.001), but there was still overlap between the groups. CONCLUSION: Doppler-derived indexes, which have previously been recommended for the assessment of severity in chronic liver disease, are difficult to reproduce reliably and therefore have a limited clinical role in the noninvasive assessment of hepatic fibrosis or inflammation.


Asunto(s)
Hepatitis C/diagnóstico por imagen , Hígado/diagnóstico por imagen , Estudios de Cohortes , Femenino , Humanos , Hígado/irrigación sanguínea , Hígado/patología , Cirrosis Hepática/diagnóstico por imagen , Masculino , Estudios Prospectivos , Índice de Severidad de la Enfermedad , Ultrasonografía Doppler
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