RESUMEN
A 57-year-old man with a family history of aortic aneurysm was found, during assessment of unexplained fever, to have an infrarenal aortic aneurysm requiring immediate repair. Dilatation of popliteal and iliac arteries was also present. Progressive aortic root dilatation with aortic regurgitation was documented from 70 years leading to valve-sparing aortic root replacement at 77 years, at which time genetic studies identified a likely pathogenic FBN1 missense variant c.6916C > T (p.Arg2306Cys) in exon 56. The proband's lenses were normally positioned and the Marfan syndrome (MFS) systemic score was 0/20. Cascade genetic testing identified 15 other family members with the FBN1 variant, several of whom had unsuspected aortic root dilatation; none had ectopia lentis or MFS systemic score ≥ 7. Segregation analysis resulted in reclassification of the FBN1 variant as pathogenic. The combination of thoracic aortic aneurysm and dissection (TAAD) and a pathogenic FBN1 variant in multiple family members allowed a diagnosis of MFS using the revised Ghent criteria. At 82 years, the proband's presenting abdominal aortic aneurysm was diagnosed retrospectively to have resulted from IgG4-related inflammatory aortopathy.
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Aneurisma de la Aorta/genética , Fibrilina-1/genética , Predisposición Genética a la Enfermedad , Síndrome de Marfan/genética , Anciano , Anciano de 80 o más Años , Aneurisma de la Aorta/complicaciones , Aneurisma de la Aorta/patología , Exones , Femenino , Pruebas Genéticas , Humanos , Inmunoglobulina G/genética , Masculino , Síndrome de Marfan/complicaciones , Síndrome de Marfan/fisiopatología , Persona de Mediana Edad , MutaciónRESUMEN
The application of MRI as a non-invasive, quantitative tool for diagnosing lumbar intervertebral disc degeneration is currently an area of active research. The objective of this study was to examine, in vitro, the efficacy of a manganese chloride phantom-based MRI technique for quantitatively assessing lumbar disc composition and degenerative condition. Sixteen human lumbar discs were imaged ex vivo using T2-weighted MRI, and assigned a quantitative grade based on the relative signal intensities of nine phantoms containing serial concentrations of manganese chloride. Discs were then graded macroscopically for degenerative condition, and water and uronic acid (glycosaminoglycan) contents were determined. MRI ranking exhibited significant and strong negative correlation with nucleus pulposus uronic acid content (r = -0.78). MRI grades were significantly higher for degenerate discs. The technique described presents immediate potential for in vitro studies requiring robust, minimally invasive and quantitative determination of lumbar disc composition and condition. Additionally, the technique may have potential as a clinical tool for diagnosing lumbar disc degeneration as it provides a standardised series of reference phantoms facilitating cross-platform consistency, requires short scan times and simple T2-weighted signal intensity measurements.
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Cloruros , Degeneración del Disco Intervertebral/patología , Disco Intervertebral/patología , Vértebras Lumbares/patología , Imagen por Resonancia Magnética/métodos , Compuestos de Manganeso , Adulto , Anciano , Anciano de 80 o más Años , Cloruros/química , Imagen de Difusión por Resonancia Magnética , Humanos , Procesamiento de Imagen Asistido por Computador , Técnicas In Vitro , Disco Intervertebral/metabolismo , Degeneración del Disco Intervertebral/metabolismo , Imagen por Resonancia Magnética/instrumentación , Compuestos de Manganeso/química , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Sensibilidad y Especificidad , Ácidos Urónicos/metabolismoRESUMEN
Muscle injury is common among athletes, and imaging is increasingly being used to confirm injury, to assess its location, extent, and severity, and on occasion to make inferences regarding prognosis and timing of return to sports. Ultrasound and magnetic resonance imaging (MRI) are accurate for diagnosis of acute injuries, but measurements of the extent of injury (cross-sectional area and longitudinal extent of muscle injury adjacent to the musculotendinous junction) have also been shown to correlate with athlete prognosis and recovery time. Specifically, normal MRI studies shortly after injury are associated with rapid (1- to 2-week) recovery and low risk of recurrent injury. Abnormal muscle cross-sectional area >55% is associated with a convalescence interval of >6 weeks, but larger measurements are not clearly associated with higher recurrence risk. The clinical value of follow-up imaging before return to competition is not established, but residual muscle abnormality is often present at this time.
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Traumatismos en Atletas/diagnóstico , Imagen por Resonancia Magnética/métodos , Músculo Esquelético/lesiones , Ultrasonografía/métodos , Traumatismos en Atletas/diagnóstico por imagen , Humanos , Puntaje de Gravedad del Traumatismo , Pronóstico , Recuperación de la Función , Recurrencia , Factores de Riesgo , Factores de Tiempo , Cicatrización de Heridas/fisiologíaRESUMEN
PURPOSE: An extensive body of literature demonstrates a strong correlation between intervertebral disk (IVD) hydration status (HS) and functional spinal integrity. However, to date, in vivo IVD HS assessment has relied largely on subjective and nonrepeatable measures. The aim of this study was to establish the consistency of signal homogeneity of a novel semisolid-state manganese chloride (MnCl2)-based phantom for HS correlation using conventional magnetic resonance (MR) imaging. MATERIALS AND METHODS: Sixteen MnCl2 phantoms, of increasing relative molar concentration (range 0.01 to 2.9 mM), underwent axial MR imaging. Phantom signal-to-noise ratio measures were recorded for each concentration on several sequence types. Coefficient of variance data were calculated to determine the degree of MR signal variation at each concentration. RESULTS: Analysis of variance testing suggested no significant difference in coefficient of variance data derived from phantom signal intensities using either T1- (P = .13) or T2-weighted sequence types (P = .96), suggesting a high degree of relative signal homogeneity. CONCLUSIONS: The findings of this study suggest that a MnCl2 phantom combined with a nonfield reactive, semirigid, gelatin suspension media can produce a predictable, concentration-related, homogeneous MR signal response. This may be an appropriate base material for a noninvasive model to allow accurate quantification of the hydration status of the in vivo human IVD.
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Agua Corporal/metabolismo , Cloruros , Interpretación de Imagen Asistida por Computador/métodos , Disco Intervertebral/anatomía & histología , Disco Intervertebral/metabolismo , Imagen por Resonancia Magnética/instrumentación , Imagen por Resonancia Magnética/métodos , Compuestos de Manganeso , Fantasmas de Imagen , Humanos , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadRESUMEN
BACKGROUND: Little data exist on the results of treatment for sports-related chronic groin injury. HYPOTHESIS: Sports-related chronic groin injury treated with a conservative (rest) program results in a satisfactory outcome. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Professional Australian male football players, at the end of the playing season, had their groin injury diagnosed using specific clinical and magnetic resonance imaging (MRI) criteria. Those assessed as having a non-hip-related cause for their chronic groin injury were treated principally by 12 weeks of complete rest from active weightbearing activities. Response to treatment was assessed at different stages of rehabilitation by recording the number of athletes who had returned to playing football and the number of athletes without symptoms. RESULTS: Twenty-seven athletes were considered to have chronic groin injury. Clinical and MRI (pubic bone marrow edema N = 26 [96%]), hyperintense line N = 25 [93%]) criteria suggested a pubic bone stress injury as diagnosis for the chronic groin injury. Eighty-nine percent of athletes returned to sport in the subsequent playing season, with 100% having returned by the second playing season after diagnosis. Forty-one percent of the athletes were without symptoms at the commencement of the following playing season, rising to 67% by the end of that playing season. CONCLUSIONS: Conservative management of athletic chronic groin injury resulted in an excellent outcome when assessed by the return to sport criterion. However, the results were only satisfactory if the criterion of ongoing symptoms after treatment was used. More research is needed to compare the efficacy of all treatments that are used in this troublesome condition.
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Traumatismos en Atletas/rehabilitación , Ingle/lesiones , Evaluación de Resultado en la Atención de Salud , Hueso Púbico/lesiones , Adolescente , Adulto , Traumatismos en Atletas/diagnóstico , Traumatismos en Atletas/diagnóstico por imagen , Enfermedad Crónica/rehabilitación , Ingle/diagnóstico por imagen , Humanos , Masculino , Hueso Púbico/diagnóstico por imagen , Radiografía , Fútbol , Australia del SurRESUMEN
Although a restricted hip range of motion has been previously associated with chronic groin injury the temporal course of this association remains unclear. Accordingly the purpose of this prospective cohort study was to report preliminary findings examining whether hip joint range of motion restriction is associated with subsequent onset of athletic chronic groin injury. End-range internal and external hip joint range of motion was determined in 29 elite Australian football players, without previous history of groin injury. The players were followed for two subsequent playing seasons for the development of chronic groin injury. Four athletes developed chronic groin injury defined as at least 6 weeks of groin pain and missing match playing time. In athletes that developed chronic groin injury a lower body weight (p=0.02) and reduced total hip joint range of motion (p=0.03) were found to be associated. This study suggests that hip stiffness is associated with later development of chronic groin injury and as such may be a risk factor for this condition. This work should be viewed as preliminary and caution is advised in applying the conclusion to clinical practice as the numbers in this study were small.
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Traumatismos Abdominales/fisiopatología , Traumatismos en Atletas/fisiopatología , Ingle/lesiones , Articulación de la Cadera/fisiopatología , Traumatismos Abdominales/diagnóstico , Adulto , Traumatismos en Atletas/diagnóstico , Peso Corporal , Enfermedad Crónica , Estudios de Cohortes , Fútbol Americano/lesiones , Humanos , Masculino , Estudios Prospectivos , Rango del Movimiento Articular , Análisis de Regresión , Factores de RiesgoRESUMEN
PURPOSE: This study aimed to develop a manganese chloride (MnCl2)-based phantom model that would allow progressive quantitative assessment of tissue hydration based on observed magnetic resonance (MR) imaging signal intensity (SI) linearity characteristics. MATERIALS AND METHODS: The study was performed using a progressive signal refinement technique that allowed development of an imaging tool for semiquantitative sequential discrimination of MR signal responses. A series of 82 phantoms comprising a gelatin-set MnCl2 composite were imaged under basic T1- and T2-weighted conditions. MR SI measurements were taken using region-of-interest selection, and MnCl2 concentrations were adjusted to allow development of a pair of 8-tube phantoms. These phantoms permitted progressive incremental assessment of hydration based on fundamental MR SI response. RESULTS: Statistical analysis showed that phantom MR signal response linearity can be achieved using the phantoms described under both T1 and T2 imaging conditions, yielding R2 values of 0.97 and 0.94, respectively. CONCLUSION: This novel MnCl2-based phantom can be used as a noninvasive reference standard for quantitative classification of in vivo tissue hydration based on routine clinical MR imaging sequences. Progressive correlation testing using a human cartilage sample should be performed to further refine the model for clinical application.
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Cloruros , Disco Intervertebral/patología , Imagen por Resonancia Magnética/instrumentación , Compuestos de Manganeso , Fantasmas de Imagen , Humanos , Estudios ProspectivosRESUMEN
BACKGROUND: Laparoscopic adjustable gastric banding (LAGB) requires surgical access to the gastroesophageal junction, which may be compromised by the enlarged, fatty liver that is frequently encountered in the obese. Liver size appears reduced and surgical access improved following preoperative weight loss with Optifast Very Low Calorie Diet (VLCD). The aim of this study was to assess the effects of 6 weeks Optifast VLCD on liver volume and fat content. METHODS: 18 morbidly obese subjects underwent magnetic resonance imaging and spectroscopy to measure liver size and fat content before and after intensive treatment with Optifast VLCD for 6 weeks. RESULTS: All subjects completing 6 weeks Optifast VLCD lost weight. Body weight and BMI (median [interquartile range]) reduced from 119.7 [111.9-131.3] kg and 44 [40-51] kg/m(2) respectively, to 110.6 [98.0124.5] kg and 40 [36-47] kg/m(2), P<0.001. Median excess weight loss (EWL) was 15.1 [9.6-21.1]%. Baseline liver volume and fat content were related (r=0.633, P=0.005). After 6 weeks Optifast VLCD, there was a 14.7% reduction in mean liver volume (P<0.001) and a 43% reduction in mean liver fat (P=0.016). The change in liver volume was predicted by the change in the liver fat (r = 0.610, P=0.012). CONCLUSION: This study has demonstrated that a 6 week diet with Optifast VLCD results in significant related reductions in liver size and liver fat content. This suggests that the reduction in liver volume is due to loss of fat. The reduction in liver fat and volume likely accounts for the perceived improved operability in patients undergoing LAGB.
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Tejido Adiposo/química , Restricción Calórica , Hígado/química , Hígado/patología , Obesidad Mórbida/dietoterapia , Adulto , Estudios Transversales , Femenino , Gastroplastia , Humanos , Laparoscopía , Imagen por Resonancia Magnética , Masculino , Obesidad Mórbida/metabolismo , Obesidad Mórbida/patología , Tamaño de los Órganos/fisiologíaRESUMEN
STUDY DESIGN: Prospective cohort study. OBJECTIVE: To examine clinical and magnetic resonance imaging (MRI) features of hamstring muscle injury to determine if any are predictive for recurrent injury. BACKGROUND: Hamstring muscle strain injury and subsequent recurrent injury are common. Little information exists on factors that may increase the risk for recurrent injury. METHODS AND MEASURES: The subjects were athletes from 3 professional Australian Rules football teams (n = 162). Anthropometric measurements, clinical signs, convalescent interval, and MRI assessment and measurement were undertaken and recorded in athletes with hamstring muscle strain injury. Athletes were followed for the presence, or absence, of recurrent injury to the same-side posterior thigh over the same and subsequent playing seasons. RESULTS: Thirty athletes met criteria for hamstring injury. Twelve (40%) of 30 athletes had recurrent injury within the same season, with an additional 7 athletes having recurrent injury in the subsequent season. None of the features examined were associated with increased recurrent injury risk within the same playing season. Statistical analysis demonstrated that when combining the same with the subsequent playing season a larger size of initial hamstring injury, as measured by MRI, was associated with an increased risk for recurrent injury (P<.01). A measured transverse size of injury greater than 55% of the muscle, or calculated volume of injury greater than 21.8 cm3, resulted in an increased risk for hamstring recurrence of 2.2 (95% CI, 0.88-5.32) and 2.3 (95% CI, 0.94-5.81) times, respectively, when compared to athletes with hamstring injuries below these measurements. CONCLUSIONS: A larger size of hamstring injury was indicative of higher risk for recurrent injury but only after the subsequent playing season was considered along with the same playing season. None of the other parameters tested, including a shorter convalescent interval and clinical features, were associated with an increased risk for recurrent injury. However, due to low sample size the certainty of these conclusions may be limited.
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Imagen por Resonancia Magnética , Músculo Esquelético/lesiones , Examen Físico , Esguinces y Distensiones/epidemiología , Muslo/lesiones , Adulto , Antropometría , Humanos , Masculino , Medición de Riesgo , Fútbol , Australia del Sur/epidemiología , Medicina Deportiva , Esguinces y Distensiones/diagnóstico , Esguinces y Distensiones/fisiopatologíaRESUMEN
The development and validation of a virtual generic 3D model of the distal femur using computer graphical methods is presented. The synthesis of the generic model requires the following steps: acquisition of bony 3D morphology using standard computed tomography (CT) imaging; alignment of 3D models reconstructed from CT images with a common coordinate system; computer graphical sectioning of the models; extraction of bone contours from the image sections; combining and averaging of extracted contours; and 3D reconstruction of the averaged contours. The generic models reconstructed from the averaged contours of six cadaver femora were validated by comparing their surface geometry on a point to point basis with that of the CT reconstructed reference models. The mean errors ranged from 0.99 to 2.5 mm and were in agreement with the qualitative assessment of the models.
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Fémur/anatomía & histología , Fémur/fisiología , Interpretación de Imagen Asistida por Computador/métodos , Imagenología Tridimensional/métodos , Modelos Anatómicos , Modelos Biológicos , Anciano , Anciano de 80 o más Años , Cadáver , Simulación por Computador , Femenino , Fémur/diagnóstico por imagen , Humanos , Técnicas In Vitro , Masculino , Radiografía , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadRESUMEN
BACKGROUND: Weight loss beyond 6 months following laparoscopic adjustable gastric banding (LAGB) is associated with a preferential mobilization of visceral adipose tissue and an improvement in insulin sensitivity in insulin resistant subjects. Because the rate of weight loss is greatest in the first 3 months after LAGB, we investigated the impact of LAGB on changes in regional lipid deposition and insulin sensitivity over this period. METHODS: 10 female obese non-diabetic subjects underwent magnetic resonance (MR) imaging and spectroscopy before and 12 weeks after LAGB (using the Swedish band), for the quantification of abdominal subcutaneous and visceral adipose tissue areas and intrahepatic lipid. Fasting blood free fatty acids were analyzed. Insulin sensitivity was monitored by fasting insulin and homeostasis model assessment (HOMA). RESULTS: Median weight loss 12 weeks after gastric banding was 9.5 kg [interquartile range (IQR): -16.5 to -6]. There were significant reductions in median abdominal subcutaneous (-20% [IQR: -24 to -13]) and visceral (-15% [IQR: -49 to -8]) adipose tissue depots as well as plasma free fatty acids (-34% [IQR: -79 to -8]). The amount of weight lost was directly proportional to the initial BMI (r=0.778; P=0.008). Visceral fat loss was proportional to initial visceral adiposity (r=0.80, P=0.01). There was no significant improvement in insulin sensitivity. CONCLUSION: Significant fat loss occurs 3 months after LAGB. The absence of a concurrent improvement in insulin sensitivity may reflect the relatively small reduction in visceral adipose tissue at this stage. Improvement in insulin sensitivity beyond 3 months after LAGB may be due to the continued loss of visceral adipose tissue.
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Adiposidad/fisiología , Glucemia/metabolismo , Gastroplastia , Insulina/sangre , Obesidad Mórbida/metabolismo , Pérdida de Peso , Grasa Abdominal/metabolismo , Grasa Abdominal/patología , Adulto , Estudios de Cohortes , Ayuno/fisiología , Femenino , Humanos , Laparoscopía , Hígado/metabolismo , Hígado/patología , Persona de Mediana Edad , Obesidad Mórbida/patología , Obesidad Mórbida/cirugía , Factores de TiempoRESUMEN
BACKGROUND: Little is known about the clinical features of posterior thigh injuries and their contribution to accurate diagnosis and prognostic assessment of hamstring muscle strain injury. HYPOTHESES: The clinical features of posterior thigh injury can be used to diagnose hamstring muscle strain and to predict duration of absence from competition. STUDY DESIGN: Prospective clinical study. METHODS: For two playing seasons, the clinical features of posterior thigh injury, timing of injury, and playing days lost were recorded for Australian Rules football players. Magnetic resonance imaging was used to confirm hamstring muscle injury. RESULTS: Posterior thigh injuries associated with pain and tenderness were recorded for 83 players, with magnetic resonance imaging confirming hamstring injury in 68 (82%). Most of the hamstring injuries were sudden onset (62; 91%) and occurred after a significant warm-up period (57; 84%). Of the patients whose injuries were sudden onset and occurred after the warm-up period (N = 59), 57 (97%) had hamstring muscle strain detected on magnetic resonance imaging. Hamstring muscle injury confirmed by magnetic resonance imaging was associated with a longer absence from competition (mean, 27 days) than injuries where no hamstring injury was detected (mean, 16 days). CONCLUSIONS: The clinical features of hamstring injury typically include sudden onset, pain, and tenderness, although exceptions do occur. Muscle fatigue may be important in the pathogenesis of hamstring injury.
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Fútbol Americano/lesiones , Imagen por Resonancia Magnética , Músculo Esquelético/lesiones , Esguinces y Distensiones/diagnóstico , Muslo/lesiones , Adulto , Distribución de Chi-Cuadrado , Humanos , Masculino , Examen Físico , Pronóstico , Estudios ProspectivosRESUMEN
AIM: Carboplatin dosing depends on accurate glomerular filtration rate (GFR) estimation. There is a lack of clinical agreement about carboplatin dosing when the GFR measurement is very high (>110 mL/min). METHODS: A retrospective audit of pre-chemotherapy 99m technetium (Tc) diethylenetriamene pentaacetate (DTPA) radionuclide GFR estimations and patients' chart review were performed from January 2006 to May 2009. The primary objective was to determine the prevalence of patients with a high GFR and the incidence of myelotoxicity in this group. RESULTS: Overall 18 of 148 treated patients (14%) measured GFR >110mL/min. The GFR values of six of the 18 patients were capped for dose calculation. In eight patients a measured GFR corrected for body surface area was used and in four the actual measured GFR was used for dose calculation. In total, 63 cycles of chemotherapy were delivered. Grade III or IV myelotoxicity accounted for 37% (15/41) of all myelotoxicities. Neutropenia accounted for almost 39% of all myelotoxicities (16/41). Two patients (11%) were hospitalized due to febrile neutropenia. Eight patients (40%) had dose reduction and four (20%) had treatment delays due to myelotoxicity. The frequency of myelotoxicity was high irrespective of the GFR used (corrected or uncorrected) in calculating the chemotherapy dose. CONCLUSION: High values of GFR, by 99mTc DTPA radionuclide measurement, are a common finding in pre-chemotherapy patients irrespective of age. Carboplatin dosing patterns in this group of patients vary among treating oncologists and a standardized approach is needed.
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Carboplatino/administración & dosificación , Riñón/efectos de los fármacos , Riñón/fisiopatología , Neoplasias/tratamiento farmacológico , Neoplasias/fisiopatología , Adulto , Anciano , Anciano de 80 o más Años , Esquema de Medicación , Femenino , Tasa de Filtración Glomerular/efectos de los fármacos , Humanos , Riñón/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Neoplasias/diagnóstico por imagen , Prevalencia , Cintigrafía , Radiofármacos , Estudios Retrospectivos , Pentetato de Tecnecio Tc 99m , Adulto JovenRESUMEN
Weight loss after laparoscopic adjustable gastric banding surgery (LAGB) is associated with mobilization of adipose tissue from a variety of depots. We sought to evaluate and relate abdominal and hepatic lipid deposition in an obese female population 3 and 12 months after LAGB. We related changes in these depots to markers of insulin sensitivity. Eighteen female obese subjects underwent magnetic resonance imaging and spectroscopy before and 3 and 12 months after LAGB for the quantification of abdominal subcutaneous (ABSAT) and visceral (VAT) adipose tissue areas and liver fat content (LFAT). Fasting blood free fatty acids (FFA) were analyzed. Insulin sensitivity was assessed by the homeostasis model assessment of insulin resistance index (HOMA-R). Mean weight loss 3 and 12 months after LAGB was 9.8 +/- 1.1 kg and 20.0 +/- 2.2 kg, respectively. Postoperatively, VAT area loss exceeded ABSAT area loss in the cohort as a whole and when divided according to preoperative liver fat stores. Three months after LAGB, reductions had occurred in VAT and ABSAT areas (both P < .01) and in FFA (P < .05). Twelve months after LAGB, further significant reductions (P < .01) occurred in VAT and ABSAT areas but not in FFA. No significant reduction occurred in LFAT at either time point in the group as a whole. In those with preoperative hepatic steatosis (LFAT > approximately 5%, n = 7), LFAT fell by 42% (P = .036) 3 months after LAGB, with a total reduction of 50% (P = .027 cf baseline) occurring by 12 months. There was an improvement in HOMA-R at 12 months (1.9 +/- 0.3 cf 2.9 +/- 0.5 at baseline, P = .04) but not 3 months (2.7 +/- 0.4). Preoperatively, LFAT related significantly to VAT area (r = 0.67, P = .003) and HOMA-R (r = 0.497, P = .04) but not ABSAT area. Postoperatively at both 3 and 12 months, LFAT continued to relate to VAT area (r = 0.63, P < .01 at both time points) but not HOMA-R. The changes in LFAT and VAT area were unrelated postoperatively. Abdominal adipose tissue loss was greater from the visceral than subcutaneous depots, suggesting that insulin sensitivity may not be an important determinant of selective lipid depot loss. The lack of a significant change in liver fat in the group as a whole may relate to low preoperative liver fat stores and to high postoperative dietary fat intakes. Preoperative liver fat stores did not influence insulin sensitivity or abdominal lipid changes during weight loss. Liver fat content and VAT area interrelated more closely than either related to ABSAT area, suggesting differing regulatory pathways for fat mobilization from ABSAT and VAT depots but possibly similar pathways for storage and mobilization of fat in the liver and viscerally.
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Adiposidad , Cirugía Bariátrica , Hígado/metabolismo , Obesidad/cirugía , Grasa Abdominal , Adulto , Femenino , Estudios de Seguimiento , Humanos , Imagen por Resonancia Magnética , Persona de Mediana Edad , Resultado del Tratamiento , Adulto JovenRESUMEN
BACKGROUND: Emerging longitudinal data appear to demonstrate an alarming trend towards an increasing prevalence of osteolysis-induced mechanical failure, following total knee replacement (TKR). Even with high-quality multi-plane X-rays, accurate pre-surgical evaluation of osteolytic lesions is often difficult. This is likely to have an impact on surgical management and provides reasonable indication for the development of a model allowing more reliable lesion assessment. The aim of this study, using a simulated cadaver model, was to explore the accuracy of rapid spiral computed tomography (CT) examination in the non-invasive evaluation of peri-prosthetic osteolytic lesions, secondary to TKR, and to compare this to conventional X-ray standards. METHODS: A series of nine volume-occupying defects, simulating osteolytic lesions, were introduced into three human cadaveric knees, adjacent to the TKR implant components. With implants in situ, each knee was imaged using a two-stage conventional plain X-ray series and rapid-acquisition spiral CT. A beam-hardening artefact removal algorithm was employed to improve CT image quality.After random image sorting, 12 radiologists were independently shown the series of plain X-ray images and asked to note the presence, anatomic location and 'size' of osteolytic lesions observed. The same process was repeated separately for review of the CT images. The corresponding X-ray and CT responses were directly compared to elicit any difference in the ability to demonstrate the presence and size of osteolytic lesions. RESULTS: Access to CT images significantly improved the accuracy of recognition of peri-prosthetic osteolytic lesions when compared to AP and lateral projections alone (P = 0.008) and with the addition of bi-planar oblique X-rays (P = 0.03). No advantage was obtained in accuracy of identification of such lesions through the introduction of the oblique images when compared with the AP and lateral projections alone (P = 0.13) CONCLUSION: The findings of this study suggest that peri-prosthetic osteolytic lesions can be reliably described non-invasively using a simple, rapid-acquisition CT-based imaging approach. The low sensitivity of conventional X-ray, even with provision of supplementary bi-planar 45 degrees oblique views, suggests a limited role for use in situ for TKR implant screening where peri-prosthetic osteolytic lesions are clinically suspected. In contrast, the accuracy of CT evaluation, linked to its procedural ease and widespread availability, may provide a more accurate way of evaluating osteolysis around TKRs, at routine orthopaedic follow up. These findings have direct clinical relevance, as accurate early recognition and classification of such lesions influences the timing and aggressiveness of surgical and non-operative management strategies, and also the nature and appropriateness of planned implant revision or joint-salvaging osteotomy procedures.
RESUMEN
BACKGROUND: There is little scientific evidence available regarding the pathologic basis for chronic groin injury in athletes, a known difficult clinical problem. HYPOTHESIS: Histological analysis of the superior pubic ramus in athletes with diagnosed chronic groin injury may reveal the nature of the pathologic process. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Ten athletes with a diagnosis of chronic groin injury by clinical criteria (at least 6 weeks of pain) and magnetic resonance imaging criteria (unequivocal increase in T2 signal intensity) underwent bone biopsy of the superior pubic ramus. The biopsy site was located in the parasymphyseal region in the area of increased magnetic resonance image signal intensity. Histologic analysis of the specimens was then undertaken. RESULTS: Evidence of new woven bone was seen in all biopsy specimens. Signs of old bony injury were seen in 8 of the 10 specimens. There was no evidence of inflammation or osteonecrosis. CONCLUSION: Histologic analysis of bone biopsy specimens taken from the parasymphyseal pubic bone region with magnetic resonance imaging T2-weighted increased signal intensity of athletes diagnosed by clinical and magnetic resonance imaging criteria as having chronic groin injury demonstrates new woven bone formation. This is consistent with the athlete having a bone stress injury that may contribute significantly to athletic groin pain.
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Traumatismos en Atletas/patología , Ingle/lesiones , Hueso Púbico/patología , Biopsia , Enfermedad Crónica , Fracturas por Estrés/patología , Humanos , Imagen por Resonancia Magnética , Masculino , Hueso Púbico/citología , Hueso Púbico/lesionesRESUMEN
AIM: To compare regional lipid deposition and insulin sensitivity after differing weight loss strategies: very low calorie diet (VLCD) and laparoscopic adjustable gastric banding (LAGB). METHOD: Thirty-nine obese women underwent anthropometry, proton magnetic resonance (MR) spectroscopy for assessment of liver fat (LFAT) and MR imaging for visceral (VAT) and subcutaneous abdominal fat volume (SAT) determination. Fasting blood was taken for insulin, glucose and free fatty acid (FFA) analysis. Measurements were repeated after 6-weeks Optifast VLCD (n = 14) or 3 months after LAGB (n = 25). RESULTS: Similar, significant (p < 0.001) weight loss occurred after VLCD (8%) and LAGB (9%). Both interventions induced significant (p < 0.001) and similar reductions in body mass index (BMI) and waist circumference, and in SAT and VAT (VLCD p < 0.05, LAGB p < 0.001). LFAT fell only after VLCD (p < 0.05). Plasma FFA only fell after LAGB (p < 0.05). Homeostasis model assessment (HOMA-R) improved only following VLCD (p < 0.05). No relations were detected between the changes in LFAT, VAT and SAT. The change in LFAT related to the change in HOMA-R in both interventions combined (r = 0.410, p = 0.013) and in the VLCD group (r = 0.660, p = 0.020). There was no change in relative dietary fat intake after LAGB (p = 0.11). CONCLUSION: Caloric and fat restriction for 6 weeks (VLCD) reduces weight, SAT, VAT, LFAT and HOMA-R. Less severe caloric restriction for 12 weeks (LAGB) causes significant loss of weight, VAT and SAT but no detectable change in LFAT and HOMA-R. Following weight loss, a change in LFAT is related more to changes in insulin sensitivity or dietary fat than to abdominal adiposity loss.
RESUMEN
The clinical assessment of groin pain in athletes is difficult, with the lack of specific clinical tests being in part responsible. Three pain provocation tests used in the diagnosis of chronic groin pain are described and their relationship to defined clinical and MRI criteria has been assessed. Eighty-nine Australian Rules football players with and without groin symptoms underwent clinical examination followed by history. Three pain provocation tests were performed (named as the Single Adductor, Squeeze and Bilateral Adductor tests). All athletes subsequently underwent MRI of their groin region for the presence of significant pubic bone marrow oedema (BMO). Of the 89, 47 were defined as having chronic groin pain, and 46 had significant BMO with 37 having both chronic groin pain and BMO. The three pain provocation tests demonstrated only moderate sensitivity (range 30-65%). Positive predictive values were moderate to high (67-93%) depending upon the individual test. The Bilateral Adductor test was the most sensitive test with the highest positive predictive values. The high specificity (88-93%) demonstrated should be treated with caution due to the study methodology. Three pain provocation tests of potential value in assessing chronic groin pain in athletes are described. If positive, all three pain provocation tests demonstrated a high likelihood for the athlete having MR-detected parasymphyseal pubic BMO. Further research is required on assessing the clinical usefulness of these tests.
Asunto(s)
Fútbol Americano/lesiones , Ingle/lesiones , Dolor/etiología , Hueso Púbico/lesiones , Fútbol/lesiones , Enfermedades de la Médula Ósea/complicaciones , Enfermedades de la Médula Ósea/diagnóstico , Enfermedad Crónica , Estudios Transversales , Edema/complicaciones , Edema/diagnóstico , Humanos , Imagen por Resonancia Magnética , Masculino , Estudios Prospectivos , Sensibilidad y EspecificidadRESUMEN
A case of a subperiosteal aneurysmal bone cyst with adjacent bone marrow oedema is presented. Aneurysmal bone cysts have been well documented in the published literature; however, relatively few have been observed in a subperiosteal location, and associated bone marrow oedema in the absence of a demonstrable pathological fracture is a rare finding. Aneursymal bone cyst should be considered in the differential diagnosis of subperiosteal bone lesions and may be associated with bone marrow oedema.
Asunto(s)
Quistes Óseos Aneurismáticos/diagnóstico , Edema/diagnóstico , Adulto , Quistes Óseos Aneurismáticos/diagnóstico por imagen , Quistes Óseos Aneurismáticos/cirugía , Médula Ósea/patología , Diagnóstico Diferencial , Edema/diagnóstico por imagen , Edema/cirugía , Femenino , Fémur , Humanos , Imagen por Resonancia Magnética , Periostio , Tomografía Computarizada por Rayos X , UltrasonografíaRESUMEN
OBJECTIVE: The purpose of this study was to examine relationships between MR imaging measurements of the extent of hamstring injury and the amount of time lost from competition in a group of athletes. SUBJECTS AND METHODS: Thirty-seven athletes with suspected hamstring injury underwent T1 and inversion recovery T2 turbo spin-echo MR imaging in axial and sagittal planes. The presence and dimensions of abnormal focal intra- and extramuscular T2 hyperintensity were independently recorded by two radiologists, and the muscles involved and intramuscular location of injury were noted. The percentage of abnormal cross-sectional muscle area, abnormal muscle volume, and length of extramuscular T2 hyperintensity were measured from T2-weighted images depicting the maximal extent of the injury. Time (days) lost from competition was noted during follow-up. RESULTS: MR imaging detected hamstring muscle and linear extramuscular T2 hyperintensity in 30 (81%) and 25 (68%) of 37 athletes, respectively. The long head of the biceps was the dominant site of injury in 21 cases. The musculotendinous junction was involved in 28 (76%) of 37 cases. A relationship was seen between days lost from competition and percentage of abnormal muscle area (r = 0.63, p = 0.001) and volume of muscle affected (r = 0.46, p = 0.01), but only a trend for linear extramuscular T2 hyperintensity (r = 0.33, p = 0.12) was shown. CONCLUSION: Rehabilitation time was related to MR measurements such as the percentage of abnormal muscle area and approximate volume of muscle injury. Hamstring injury most frequently involved the long head of the biceps femoris muscle, and involvement of the intramuscular tendon was common.