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In forensic medicine practice, age estimation-both in living and deceased individuals-can be requested due to legal requirements. Radiologic methods, such as X-rays, for the estimation of bone age have been discussed, and ethical concerns have been raised. Given these factors, radiologic methods that reduce radiation exposure have gained importance and have become one of the research topics in forensic medicine. In this study, the MR images of the ankles of patients aged between 8 and 25 years, obtained with a 3.0 T MR scanner, were evaluated retrospectively according to the staging method defined by Vieth et al. In the study, the ankle MR images of 201 cases (83 females and 118 males) with sagittal T1-weighted turbo spin echo and T2-weighted short tau inversion recovery sequences were evaluated independently by two observers. According to the results of our study, the intra- and inter-observer agreements are at a very good level for both the distal tibial and calcaneal epiphyses. All the cases detected as stages 2, 3, and 4 in both sexes for both the distal tibial and the calcaneal epiphyses have been determined to be under the age of 18 years. According to the data obtained from our study, we consider that stage 5 for males and stage 6 for both sexes in the distal tibial epiphysis and stage 6 for males in the calcaneal epiphysis can be used to estimate the age of 15 years. As far as we know, our study is the first to evaluate ankle MR images with the method defined by Vieth et al. Further studies should be conducted to evaluate the validity of the procedure.
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Determinación de la Edad por el Esqueleto , Osteogénesis , Masculino , Femenino , Humanos , Niño , Adolescente , Adulto Joven , Adulto , Proyectos Piloto , Estudios Retrospectivos , Determinación de la Edad por el Esqueleto/métodos , Imagen por Resonancia Magnética/métodos , Epífisis/diagnóstico por imagenRESUMEN
BACKGROUND: 1H magnetic resonance spectroscopy (1H-MRS) can be used to study neurological disorders because it can be utilized to examine the concentrations of related metabolites. However, the diagnostic utility of different field strengths for temporal lobe epilepsy (TLE) remains unclear. The purpose of this study is to make quantitative comparisons of metabolites of TLE at 1.5T and 3.0T and evaluate their efficacy. METHODS: Our retrospective collections included the single-voxel 1H-MRS of 23 TLE patients and 17 healthy control volunteers (HCs) with a 1.5T scanner, as well as 29 TLE patients and 17 HCs with a 3.0T scanner. Particularly, HCs were involved both the scans with 1.5T and 3.0T scanners, respectively. The metabolites, including the N-acetylaspartate (NAA), creatine (Cr), and choline (Cho), were measured in the left or right temporal pole of brain. To analyze the ratio of brain metabolites, including NAA/Cr, NAA/Cho, NAA/(Cho + Cr) and Cho/Cr, four controlled experiments were designed to evaluate the diagnostic utility of TLE on 1.5T and 3.0T MRS, included: (1) 1.5T TLE group vs. 1.5T HCs by the Mann-Whitney U Test, (2) 3.0T TLE group vs. 3.0T HCs by the Mann-Whitney U Test, (3) the power analysis for the 1.5T and 3.0T scanner, and (4) 3.0T HCs vs. 1.5T HCs by Paired T-Test. RESULTS: Three metabolite ratios (NAA/Cr, NAA/Cho, and NAA/(Cho + Cr) showed the same statistical difference (p < 0.05) in distinguishing the TLE from HCs in the bilateral temporal poles when using 1.5T or 3.0T scanners. Similarly, the power analysis demonstrated that four metabolite ratios (NAA/Cr, NAA/Cho, NAA/(Cho + Cr), Cho/Cr) had similar distinction abilities between 1.5T and 3.0T scanner, denoting both 1.5T and 3.0T scanners were provided with similar sensitivities and reproducibilities for metabolites detection. Moreover, the metabolite ratios of the same healthy volunteers were not statistically different between 1.5T and 3.0T scanners, except for NAA/Cho (p < 0.05). CONCLUSIONS: 1.5T and 3.0T scanners may have comparable diagnostic potential when 1H-MRS was used to diagnose patients with TLE.
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Epilepsia del Lóbulo Temporal , Humanos , Epilepsia del Lóbulo Temporal/diagnóstico por imagen , Epilepsia del Lóbulo Temporal/metabolismo , Imagen por Resonancia Magnética , Estudios Retrospectivos , Espectroscopía de Resonancia Magnética/métodos , Lóbulo Temporal/metabolismo , Creatina/metabolismo , ColinaRESUMEN
Adrenal disease is a common problem in dogs and MRI is increasingly being used as an adjunctive diagnostic test. To date, the MRI features of normal canine adrenal glands have only been reported using 1.5-Tesla (T) MRI. The aims of this prospective, methods-comparison, exploratory study were to evaluate the effects of pulse sequence on the appearance of normal canine adrenal glands using 3 Tesla MRI. Six research beagle dogs were sampled and the following pulse sequences were acquired for each: (1) T2-weighted images using two-dimensional (2D) turbo spin-echo (TSE), single-shot spin-echo (SSTSE), and three-dimensional (3D) TSE, (2) T1-weighted images using 2D TSE, 3D TSE, and 3D turbo field echo sequences, (3) post-contrast T1-weighted images, and (4) chemical shift imaging. The signal-to-noise ratio and contrast-to-noise ratio were measured for each dog and each pulse sequence. The signal intensity, clarity of the contour, distinction of the corticomedullary junction, degrees of motion, partial volume, and chemical shift artifact, and homogeneity of the contrast enhancement were evaluated qualitatively. In all sequences, except for chemical shift imaging, the adrenal glands were visualized in both planes with successful control of motion artifacts by manual ventilation. The adrenal contour was considered to be most clearly visualized with 2D TSE. Adrenal images were acquired within the shortest time using SSTSE although the contour was less clearly visualized than with TSE. Findings from this study in normal dogs can serve as background for further 3.0-T MRI studies of dogs with adrenal disease.
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Artefactos , Imagen por Resonancia Magnética , Glándulas Suprarrenales/diagnóstico por imagen , Animales , Perros , Imagenología Tridimensional/métodos , Imagen por Resonancia Magnética/métodos , Imagen por Resonancia Magnética/veterinaria , Estudios Prospectivos , Relación Señal-RuidoRESUMEN
Purpose: To compare the diagnostic performance of 3.0 T and 1.5 T MRI in the staging of prostate cancer. Material and methods: English-language studies on the diagnostic accuracy of 3.0 T and 1.5 T MRI in prostate cancer staging published through May 2020 were searched for in relevant databases. The focus was on studies in which both 3.0 T and 1.5 T MRI were performed in the study population, to reduce interstudy heterogeneity. Pooled sensitivity, specificity, diagnostic odds ratio (DOR), and area under the receiver operating characteristic curve were determined for 3.0 T and for 1.5 T along with 95% confidence intervals (CIs). Results: Out of 8 studies identified, 4 met the inclusion criteria. 3.0 T (n = 160) had a pooled sensitivity of 69.5% (95% CI: 56.4-80.1%) and a pooled specificity of 48.8% (95% CI: 6.0-93.4%), while 1.5 T (n = 139) had a pooled sensitivity of 70.6% (95% CI: 55.0-82.5%; p = 0.91) and a pooled specificity of 41.7% (95% CI: 6.2-88.6%; p = 0.88). The pooled DOR for 3.0 T was 3 (95% CI: 0-26.0%), while the pooled DOR for 1.5 T was 2 (95% CI: 0-18.0%), which was not a significant difference (p = 0.89). Conclusions: 3.0 T has slightly better diagnostic performance than 1.5 T MRI in prostate cancer staging (3 vs. 2), although without statistical significance. Our findings suggest the need for larger, randomized trials directly comparing 3.0 T and 1.5 T MRI in prostate cancer.
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OBJECTIVE: To evaluate the effect of circular polarization (CP) and elliptical polarization (EP) of the B1 field on metal implant-induced artifacts of titanium (Ti) and cobalt-chromium (CoCr) hip arthroplasty implants at 1.5-T and 3.0-T field strengths. MATERIAL AND METHODS: In vitro Ti and CoCr total hip arthroplasty implants were evaluated using high transmit and receive bandwidth turbo spin echo (HBW-TSE) and slice encoding for metal artifact correction (SEMAC) metal artifact reduction techniques. Each technique was implemented at 1.5-T, which only allows for CP of B1 field as the system default, as well as 3.0-T, which permitted CP and EP. Manual segmentation quantified the size of the metal artifacts at the level of the acetabular cup, femoral neck, and femoral shaft. RESULTS: In the acetabular cup and femoral neck, 1.5-T CP achieved smaller artifact sizes than 3.0-T CP (28-29% on HBW-TSE, p = 0.002-0.005; 17-34% on SEMAC, p = 0.019-0.102) and 3.0-T EP (25-28% on HBW-TSE, p = 0.010-0.011; 14-36% on SEMAC, p = 0.058-0.135) techniques. In the femoral stem region, 3.0-T EP achieved more efficient artifact suppression than 3.0-T CP (HBW-TSE 44-45%, p < 0.001-0.022; SEMAC 76-104%, p < 0.001-0.022) and 1.5-T CP (HBW-TSE 76-96%, p < 0.001-0.003; SEMAC 138-173%, p = 0.003-0.005) techniques. CONCLUSION: Despite slightly superior metal reduction ability of the 1.5-T in the region of the acetabular cup and prosthesis neck, 3.0-T MRI of hip arthroplasty implants using elliptically polarized RF pulses may overall be more effective in reducing metal artifacts than the current standard 1.5-T MRI techniques, which by default implements circularly polarized RF pulses.
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Artroplastia de Reemplazo de Cadera , Artefactos , Humanos , Imagen por Resonancia Magnética , Metales , Prótesis e ImplantesRESUMEN
INTRODUCTION: Hip abductor tendinopathies are becoming increasingly recognized as clinically relevant disorders. However, knowledge about prevalence of abductor tendinopathies and associated disorders of adjacent hip articular and periarticular structures is limited. In this context, the relative diagnostic value of 1.5-T vs. 3.0-T MRI magnets has not been studied yet. MATERIALS AND METHODS: Pelvic MRI scans of 1000 hips from 500 consecutive unselected patients (341 in 3.0-T/159 in 1.5-T magnets, with standardized scanning protocols over the entire study period) were analysed for the detection of abductor tendinosis, calcifying tendinitis, partial or full-thickness tears of the M. gluteus medius (GMed) and/or -minimus (GMin) and trochanteric bursitis (TB). The occurrence of these lesions was correlated to the presence of muscle atrophy (MA) of GMed/GMin, hip joint effusion (JE) and osteoarthritis (OA). RESULTS: Peritrochanteric lesions were observed with a prevalence of 31.4% of all patients (22.3% of all hips). TB occurred almost exclusively in the presence of GMed/GMin tendinopathies. Compared to overall prevalence, patients with MA displayed lesions of GMed/GMin or TB in 70%, patients, with OA in 30% and with JE in 23%. These lesions occurred significantly more often ipsilateral to MA and OA than contralateral (MA: 76.8% vs. 23.2%, p < 0.001; OA: 64.4% vs. 35.6%, p = 0.03; JE: 62.7% vs. 37.3%, p = 0.08). Significantly more tendon lesions, in particular specific radiological diagnoses like partial/full-thickness tears, were detected by 3.0-T MRI than by 1.5 T (p = 0.019). CONCLUSIONS: Peritrochanteric lesions are a prevalent pathology that should specifically be looked for, preferably by 3.0-T MRI, independent of concomitant hip joint pathology.
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Articulación de la Cadera , Imagen por Resonancia Magnética/métodos , Tendinopatía , Tendones , Articulación de la Cadera/diagnóstico por imagen , Articulación de la Cadera/fisiología , Humanos , Interpretación de Imagen Asistida por Computador , Músculo Esquelético/diagnóstico por imagen , Músculo Esquelético/patología , Tendinopatía/diagnóstico por imagen , Tendinopatía/patología , Tendones/diagnóstico por imagen , Tendones/patologíaRESUMEN
Brain T1-weighted images using spin echo (SE) sequence has poor contrast at 3.0 Tesla magnetic resonance imaging (3.0 T MRI) systems from the influence of crosstalk and magnetized transfer (MT) effect, and prolongation of the T1 value. Therefore, improving of scan parameters has been reported such as excitation flip angle (FA) and interleave data acquisition. The purpose of this study was to show the effects of alterations of presaturation pulse amplitude and chemical shift selective (CHESS) pulse amplitude. Gray-to-white matter contrast increased with decreasing amplitude of presaturation pulse in whole brain imaging. Presaturation and CHESS pulse consist of radio frequency pulse. Therefore, both pulses have a similar effect on MT pulse. Manual alteration of presaturation pulse amplitude for each scan lacks versatility on clinical use. However, decreasing amplitude of presaturation pulse is equal to decreasing thickness of presaturation pulse. About CHESS pulse, it requires no manual alteration for each scan. For example, switching fat suppression mode from strong to weak increase T1 contrast. Our study demonstrated that using not only low excitation FA and interleave date acquisition but also low amplitude of presaturation and CHESS pulse increase the contrast in T1 SE brain scans at 3.0 T MRI.
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Encéfalo , Imagen por Resonancia Magnética , Encéfalo/diagnóstico por imagen , Humanos , Aumento de la ImagenRESUMEN
Synthetic MRI can provide proton density (PD), T1 value, T2 value for each pixel by only one data acquisition and can create various contrast-weighted images. The aim of this study is to evaluate the effect on the calculation of the T1·T2 value when changing the scan parameters for synthetic MRI. In the phantom study, when changing 1st TE/2nd TE/TR/TSE factor, the effect on the T1·T2 value calculated by synthetic MRI was examined. In the volunteer study, the brain was imaged and compared with known T1·T2 value. In phantom study, the effect on the T2 value by the 1st TE/2nd TE/TSE factor was shown. In volunteer study, there was no problem in the calculated value of brain parenchyma. However, the T2 value of cerebrospinal fluid had the error of known value. The results show that it is necessary to set appropriate scan parameters on synthetic MRI.
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Imagen por Resonancia Magnética/métodos , Adulto , Encéfalo/diagnóstico por imagen , Femenino , Humanos , Masculino , Fantasmas de Imagen , Adulto JovenRESUMEN
PURPOSE: To establish normal reference values of left ventricular (LV) and right ventricular (RV) dimension, volume, mass, and ejection fraction in a Chinese population using cardiac magnetic resonance imaging (MRI). MATERIALS AND METHODS: A total of 120 (60 males; 60 females; 23-83 years) healthy Han Chinese subjects without cardiovascular disease or risk factors were recruited. They underwent comprehensive MRI examination at 3.0T. LV/RV morphology and function were evaluated by steady-state free-procession (SSFP) sequence. Parameters were analyzed according to a standard postprocessing protocol. RESULTS: Significant differences in LV size, mass, volume, and ejection fraction (EF) between sexes were noted (all P < 0.05). After indexing using body surface area (BSA), LV end-diastolic volume (EDV), and LV mass index were greater in males than in females (76.5 vs. 68.7 mL/m, P < 0.001; 52.9 vs. 45.1 g/m, P < 0.001; respectively). LVEF was lower in males than in females (64.6% vs. 67.1%, P = 0.007, respectively). RV volume was higher and RVEF lower in males compared with females (75.3 vs. 62.7 mL/m, P < 0.001; 59.9% vs. 62.6%, P = 0.001, respectively). Age was associated significantly with indices of LV and RV volume in females (left ventricular end-diastolic volume index: r = -0.41 P = 0.001; left ventricular end-systolic volume index: r = -0.37 P = 0.004; left ventricular end-diastolic volume index: r = -0.53 P < 0.001; right ventricular end-systolic volume index: r = -0.43 P < 0.001), but not in males (all P > 0.05). CONCLUSION: These data suggest that sex and age affect ventricular parameters in healthy Han Chinese subjects without cardiovascular disease or risk factors. LEVEL OF EVIDENCE: 2 Technical Efficacy: Stage 2 J. MAGN. RESON. IMAGING 2017;45:1684-1692.
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Envejecimiento/fisiología , Pruebas de Función Cardíaca/normas , Ventrículos Cardíacos/anatomía & histología , Ventrículos Cardíacos/diagnóstico por imagen , Imagen por Resonancia Magnética/normas , Volumen Sistólico , Función Ventricular/fisiología , Adulto , Anciano , Anciano de 80 o más Años , Envejecimiento/patología , China/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valores de Referencia , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Factores Sexuales , Adulto JovenRESUMEN
OBJECTIVE: The objective of this study is to evaluate the diagnostic performance of 3D sampling perfection with application-optimized contrasts using different flip angle evolution (SPACE) sequences in the evaluation of ankle syndesmosis injuries, compared with that of conventional orthogonal MRI and oblique proton density-weighted turbo spin-echo (TSE) sequences performed with 3-T MRI. MATERIALS AND METHODS: This retrospective study included 98 patients with suspected ankle syndesmosis injuries who underwent both MRI and surgery. Fifty patients (mean [± SD] age, 34.5 ± 15.3 years) had acute injuries, and 48 patients (mean age, 28.5 ± 9.6 years) had chronic injuries. For both groups, the diagnostic performance of each MRI sequence with regard to syndesmosis injuries was evaluated. Arthroscopy findings were used as a reference standard to confirm diagnosis. RESULTS: No statistically significant differences in the sensitivity, specificity, accuracy, and AUC values were noted between images of the syndesmosis obtained using proton density-weighted TSE sequences and images of the syndesmosis obtained using 3D SPACE sequences (p > 0.05). Interobserver agreement regarding the diagnosis of both acute and chronic syndesmosis injuries was almost perfect for proton density-weighted TSE images (κ > 0.80) and was substantial for 3D SPACE images (κ > 0.75). Both methods of obtaining images of the syndesmosis had a diagnostic performance superior to that of conventional orthogonal MRI. CONCLUSION: The performance of 3D SPACE sequences is comparable to that of 2D proton density-weighted MR images for the diagnosis of acute and chronic syndesmosis injuries.
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Traumatismos del Tobillo/diagnóstico por imagen , Articulación del Tobillo/diagnóstico por imagen , Interpretación de Imagen Asistida por Computador/métodos , Imagenología Tridimensional/métodos , Posicionamiento del Paciente/métodos , Adolescente , Adulto , Anciano , Anisotropía , Femenino , Humanos , Aumento de la Imagen/métodos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Procesamiento de Señales Asistido por Computador , Adulto JovenRESUMEN
PURPOSE: To assess articular cartilage changes in the knee joint as detected on 3.0T MR imaging after 2-year follow-up in patients who underwent arthroscopic anterior cruciate ligament reconstruction (ACLR) with or without concomitant meniscal surgery. METHODS: A total of twenty-nine patients (mean age 30.3 ± 10 years), who underwent arthroscopic ACLR, received clinical and imaging follow-up at an average of 27.8 ± 4.8 months after surgery. Our patients were divided into two subgroups: eighteen patients with additional meniscal injuries at the time of arthroscopic ACLR who underwent meniscal surgery and eleven patients with intact menisci. The cartilage status of all knees at the time of arthroscopic ACLR was recorded. All patients underwent an MRI scan preoperatively and at follow-up with the same imaging protocol. Cartilage status of all knee compartments was evaluated at the time of follow-up by MR imaging and the ICRS classification. RESULTS: Deterioration of the cartilage status was found at all knee compartments of our study group, with respect to the number of cartilage defects. The cartilage of the lateral femoral condyle (LFC) was most severely affected, followed by patellar and medial femoral condyle (MFC) cartilage. A statistically significant relation was found between surgery of the medial meniscus and the development of new cartilage defects in LFC (p = 0.01) and MFC (p = 0.03) after adjusting for the site of meniscal surgery. The cartilage of LFC and the status of the medial meniscus were also found to be significantly related (p = 0.04). Partial meniscectomy was found to be associated with an increased incidence of new cartilage defects when compared to either meniscal repair or absence of meniscal surgery, although it was not statistically significant. CONCLUSION: Development of new cartilage lesions was evident after 2-year follow-up in patients with arthroscopic ACLR as detected by MR imaging. There was a multicompartmental pattern of cartilage involvement, and the lateral compartment was most severely affected. Partial meniscectomy at the time of arthroscopic ACLR could be suggested as an additional risk factor for the progression of chondral lesions. LEVEL OF EVIDENCE: Prospective comparative study, Level II.
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Lesiones del Ligamento Cruzado Anterior/cirugía , Reconstrucción del Ligamento Cruzado Anterior/métodos , Cartílago Articular/cirugía , Meniscos Tibiales/cirugía , Evaluación de Resultado en la Atención de Salud , Adolescente , Adulto , Artroscopía , Epífisis/cirugía , Femenino , Humanos , Incidencia , Imagen por Resonancia Magnética/métodos , Masculino , Estudios Prospectivos , Adulto JovenRESUMEN
OBJECTIVE: To compare two fat suppression techniques used for 3D T1-weighted sequence in breast MRI (magnetic resonance imaging), namely Dixon versus spectral fat saturation (fat sat). MATERIALS AND METHODS: All breast MRI examinations performed in a Philips 3 T unit between March 2013 and October 2015 including either a Dixon or a fat sat sequence were retrospectively analyzed. The examinations were subjectively evaluated by two independent experienced readers in a scale of 5 for overall quality of fat suppression, homogeneity of fat suppression, definition of anatomic structures and focal lesions, diagnostic confidence for axillary and internal mammary regions and the presence of artifacts, 1 corresponding to excellent and 5 to non-diagnostic quality. Contrast-to-noise-ratio (CNR) measurements for muscle and focal lesions were also performed. RESULTS: Overall 161 women (mean age 51.6 ± 12.0 years) underwent 189 MR examinations, 113 with the fat saturation and 76 with the Dixon sequence. Interobserver variability was good (kappa = 0.757). In all subjectively evaluated parameters, the Dixon sequence was superior to the fat sat (p < 0.05). Mean values of CNR for muscle and focal lesions were 9.98 (±4.2), 17.9 (±7.53) for the fat sat and 18.3 (±10.4) and 29.3 (±14.1) for the Dixon sequence, respectively (p < 0.001). CONCLUSION: 3D T1 Dixon sequence is superior to fat sat for dedicated breast MRI at 3 T, in terms of efficiency of fat suppression and image quality with the added advantage of optimal exploration of the axillary areas.
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Tejido Adiposo/diagnóstico por imagen , Neoplasias de la Mama/diagnóstico por imagen , Aumento de la Imagen/métodos , Imagen por Resonancia Magnética/métodos , Artefactos , Medios de Contraste , Femenino , Humanos , Persona de Mediana Edad , Estudios RetrospectivosRESUMEN
In legal medicine, reliable localization and analysis of hematomas in subcutaneous fatty tissue is required for forensic reconstruction. Due to the absence of ionizing radiation, magnetic resonance imaging (MRI) is particularly suited to examining living persons with forensically relevant injuries. However, there is limited experience regarding MRI signal properties of hemorrhage in soft tissue. The aim of this study was to evaluate MR sequences with respect to their ability to show high contrast between hematomas and subcutaneous fatty tissue as well as to reliably determine the volume of artificial hematomas. Porcine tissue models were prepared by injecting blood into the subcutaneous fatty tissue to create artificial hematomas. MR images were acquired at 3T and four blinded observers conducted manual segmentation of the hematomas. To assess segmentability, the agreement of measured volume with the known volume of injected blood was statistically analyzed. A physically motivated normalization taking into account partial volume effect was applied to the data to ensure comparable results among differently sized hematomas. The inversion recovery sequence exhibited the best segmentability rate, whereas the T1T2w turbo spin echo sequence showed the most accurate results regarding volume estimation. Both sequences led to reproducible volume estimations. This study demonstrates that MRI is a promising forensic tool to assess and visualize even very small amounts of blood in soft tissue. The presented results enable the improvement of protocols for detection and volume determination of hemorrhage in forensically relevant cases and also provide fundamental knowledge for future in-vivo examinations.
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Hematoma/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Tejido Subcutáneo/diagnóstico por imagen , Animales , Patologia Forense , Hematoma/patología , Modelos Animales , Tejido Subcutáneo/patología , PorcinosRESUMEN
PURPOSE: To scan a volunteer population using 3.0T magnetic resonance imaging (MRI). MRI of the left ventricular (LV) structure and function in healthy volunteers has been reported extensively at 1.5T. MATERIALS AND METHODS: A population of 1528 volunteers was scanned. A standardized approach was taken to acquire steady-state free precession (SSFP) LV data in the short-axis plane, and images were quantified using commercial software. Six observers undertook the segmentation analysis. RESULTS: Mean values (±standard deviation, SD) were: ejection fraction (EF) = 69 ± 6%, end diastolic volume index (EDVI) = 71 ± 13 ml/m2 , end systolic volume index (ESVI) = 22 ± 7 ml/m2 , stroke volume index (SVI) = 49 ± 8 ml/m2 , and LV mass index (LVMI) = 55 ± 12 g/m2 . The mean EF was slightly larger for females (69%) than for males (68%), but all other variables were smaller for females (EDVI 68v77 ml/m2 , ESVI 21v25 ml/m2 , SVI 46v52 ml/m2 , LVMI 49v64 g/m2 , all P < 0.05). The mean LV volume data mostly decreased with each age decade (EDVI males: -2.9 ± 1.3 ml/m2 , females: -3.1 ± 0.8 ml/m2 ; ESVI males: -1.3 ± 0.7 ml/m2 , females: -1.7 ± 0.5 ml/m2 ; SVI males: -1.7 ± 0.9 ml/m2 , females: -1.4 ± 0.6 ml/m2 ; LVMI males: -1.6 ± 1.1 g/m2 , females: -0.2 ± 0.6 g/m2 ) but the mean EF was virtually stable in males (0.6 ± 0.6%) and rose slightly in females (1.2 ± 0.5%) with age. CONCLUSION: LV reference ranges are provided in this population-based MR study at 3.0T. The variables are similar to those described at 1.5T, including variations with age and gender. These data may help to support future population-based MR research studies that involve the use of 3.0T MRI scanners. J. Magn. Reson. Imaging 2016;44:1186-1196.
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Envejecimiento/patología , Envejecimiento/fisiología , Ventrículos Cardíacos/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Volumen Sistólico/fisiología , Función Ventricular Izquierda/fisiología , Adulto , Distribución por Edad , Anciano , Anciano de 80 o más Años , Femenino , Ventrículos Cardíacos/anatomía & histología , Humanos , Imagen por Resonancia Magnética/estadística & datos numéricos , Masculino , Tamizaje Masivo , Persona de Mediana Edad , Valores de Referencia , Distribución por Sexo , Factores Sexuales , Reino Unido/epidemiologíaRESUMEN
OBJECTIVES: To clarify the usefulness of 3.0-T MR elastography (MRE) in diagnosing the histological grades of liver fibrosis using preliminary clinical data. MATERIALS AND METHODS: Between November 2012 and March 2014, MRE was applied to all patients who underwent liver MR study at a 3.0-T clinical unit. Among them, those who had pathological evaluation of liver tissue within 3 months from MR examinations were retrospectively recruited, and the liver stiffness measured by MRE was correlated with histological results. Institutional review board approved this study, waiving informed consent. RESULTS: There were 70 patients who met the inclusion criteria. Liver stiffness showed significant correlation with the pathological grades of liver fibrosis (rho = 0.89, p < 0.0001, Spearman's rank correlation). Areas under the receiver operating characteristic curve were 0.93, 0.95, 0.99 and 0.95 for fibrosis score greater than or equal to F1, F2, F3 and F4, with cut-off values of 3.13, 3.85, 4.28 and 5.38 kPa, respectively. Multivariate analysis suggested that grades of necroinflammation also affected liver stiffness, but to a significantly lesser degree as compared to fibrosis. CONCLUSIONS: 3.0-T clinical MRE was suggested to be sufficiently useful in assessing the grades of liver fibrosis. KEY POINTS: MR elastography may help clinicians assess patients with chronic liver diseases. Usefulness of 3.0-T MR elastography has rarely been reported. Measured liver stiffness correlated well with the histological grades of liver fibrosis. Measured liver stiffness was also affected by necroinflammation, but to a lesser degree. 3.0-T MRE could be a non-invasive alternative to liver biopsy.
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Imagen Eco-Planar/métodos , Diagnóstico por Imagen de Elasticidad/métodos , Cirrosis Hepática/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , Área Bajo la Curva , Biopsia con Aguja/métodos , Imagen Eco-Planar/estadística & datos numéricos , Elasticidad , Diagnóstico por Imagen de Elasticidad/estadística & datos numéricos , Femenino , Hepatitis B Crónica/diagnóstico , Hepatitis B Crónica/patología , Hepatitis C Crónica/diagnóstico , Hepatitis C Crónica/patología , Humanos , Hígado/patología , Cirrosis Hepática/clasificación , Cirrosis Hepática/patología , Masculino , Persona de Mediana Edad , Necrosis , Curva ROC , Estudios Retrospectivos , Sensibilidad y EspecificidadRESUMEN
OBJECTIVE: To compare prospectively image quality and diagnostic confidence of flow-sensitive 3D turbo spin echo (TSE)-based non-contrast-enhanced MR angiography (NE-MRA) at 3.0 T using dual-source radiofrequency (RF) transmission with contrast-enhanced MRA (CE-MRA) in patients with peripheral arterial occlusive disease (PAOD). METHODS: After consent was obtained, 35 patients (mean age 69.1 ± 10.6 years) with PAOD stage II-IV underwent NE-MRA followed by CE-MRA. Signal-to-noise ratio and contrast-to-noise ratio were calculated. Subjective image quality was independently assessed by two radiologists and stenosis scoring was performed in 875 arterial segments. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for stenosis classification were calculated using CE-MRA as a reference method. Diagnostic agreement with CE-MRA was evaluated with Cohen's kappa statistics. RESULTS: NE-MRA provided high objective and subjective image quality at all levels of the arterial tree. Sensitivity and specificity for the detection of relevant stenosis was 91 % and 89 %, respectively; the NPV was 96 % and the PPV 78 %. There was good concordance between CE-MRA and NE-MRA in stenosis scoring. CONCLUSIONS: 3D electrocardiography (ECG)-gated TSE NE-MRA with patient-adaptive dual-source RF transmission at 3.0 T is a promising alternative for PAOD patients with contraindications for gadolinium-based contrast agents. It offers high sensitivity and NPV values in the detection of clinically relevant arterial stenosis. KEY POINTS: ⢠Flow-sensitive TSE NE-MRA is a promising technique for PAOD evaluation. ⢠Diagnostic accuracy is comparable to contrast-enhanced MRA. ⢠NE-MRA eliminates the risk of NSF in patients with renal insufficiency. ⢠Costs arising from the use of contrast agents can be avoided.
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Medios de Contraste , Electrocardiografía/métodos , Aumento de la Imagen/métodos , Imagenología Tridimensional/métodos , Angiografía por Resonancia Magnética/métodos , Enfermedad Arterial Periférica/diagnóstico por imagen , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Extremidad Inferior/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Ondas de Radio , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Relación Señal-RuidoRESUMEN
BACKGROUND: Imaging evaluation plays a crucial role in the diagnostic work-up of female infertility. In recent years, the possibility to evaluate tubal patency using 1.5 Tesla magnetic resonance (1.5T MR) has been studied. PURPOSE: To assess the feasibility of 3.0 Tesla magnetic resonance (3.0T MR) hysterosalpingography and its role in the diagnostic work-up of female infertility and to evaluate if this fast "one-stop-shop" imaging approach should be proposed as a first-line examination. MATERIAL AND METHODS: A total of 116 infertile women were enrolled in this prospective study; all underwent 3.0T MR hysterosalpingography. After standard imaging of the pelvis, tubal patency was assessed by acquiring 3D dynamic time-resolved T1-weighted (T1W) sequences during manual injection of 4-5 mL of contrast solution consisting of gadolinium and normal sterile saline. Images were evaluated by two radiologists with different experience in MR imaging (MRI). RESULTS: The examination was successfully completed in 96.5% of cases, failure rate was 3.5%. Dynamic sequences showed bilateral tubal patency in 64.3%, unilateral tubal patency in 25.9%, and bilateral tubal occlusion in 9.8%. Extratubal abnormalities were found in 69.9% of patients. Comprehensive analysis of morphological and dynamic sequences showed extratubal abnormalities in 43.1% of patients with bilateral tubal patency. CONCLUSION: 3.0T MR hysterosalpingography is a feasible, simple, fast, safe, and well-tolerated examination, which allows evaluation of tubal patency and other pelvic causes of female infertility in a single session, and it may thus represent a "one-stop-shop" solution in female infertility diagnostic work-up.
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Histerosalpingografía , Infertilidad Femenina/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Adulto , Medios de Contraste , Estudios de Factibilidad , Femenino , Gadolinio DTPA , Humanos , Estudios ProspectivosRESUMEN
BACKGROUND: Indirect magnetic resonance (MR) arthrography is a non-invasive method for shoulder imaging. However, there are no studies that have examined the diagnostic performance of indirect MR arthrography for the diagnosis of rotator cuff tears in a large patient population. PURPOSE: To assess the diagnostic performance of indirect fast spin-echo (FSE) MR arthrography for the diagnosis of rotator cuff tears at 3.0 T. MATERIAL AND METHODS: A total of 149 patients who had undergone indirect shoulder MR arthrography followed by arthroscopic surgery were enrolled in this retrospective study. Two musculoskeletal radiologists evaluated images from each patient for the presence of supraspinatus-infraspinatus (SSP-ISP) or subscapularis (SSC) tendon tears. Using the arthroscopic findings as the reference standard, the overall diagnostic performance and detection rates for SSP-ISP and SSC tendon tears were calculated. RESULTS: The sensitivity, specificity, and accuracy of readers I and II for the diagnosis of SSP-ISP tendon tears were 94% and 95%, 89% and 85%, and 93% and 93%, respectively. The sensitivity of imaging for detection of SSP-ISP tendon tears by readers I and II were 100% and 100% for full-thickness tears and 84% and 86% for partial-thickness tears, respectively. The sensitivity, specificity, and accuracy of readers I and II for the diagnosis of SSC tendon tears were 80% and 76%, 89% and 93%, and 85% and 85%, respectively. CONCLUSION: Indirect MR arthrography is useful for the detection of SSP-ISP and SSC tendon tears.
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Artrografía/métodos , Imagen por Resonancia Magnética , Lesiones del Manguito de los Rotadores , Manguito de los Rotadores/diagnóstico por imagen , Adolescente , Adulto , Anciano , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Adulto JovenRESUMEN
PURPOSE: To study liver imaging with volume acceleration-flexible (LAVA-Flex) for abdominal magnetic resonance imaging (MRI) at 3.0 T and compare the image quality of abdominal organs between LAVA-Flex and fast spoiled gradient-recalled (FSPGR) T1-weighted imaging. MATERIALS AND METHODS: Our Institutional Review Board approval was obtained in this retrospective study. Sixty-nine subjects had both FSPGR and LAVA-Flex sequences. Two radiologists independently scored the acquisitions for image quality, fat suppression quality, and artifacts and the values obtained were compared with the Wilcoxon signed rank test. According to the signal intensity (SI) measurements, the uniformity of fat suppression, the contrast between muscle and fat and normal liver and liver lesions were compared by the paired t-test. The liver and spleen SI on the fat-only phase were analyzed in the fatty liver patients. RESULTS: Compared with FSPGR imaging, LAVA-Flex images had better and more homogenous fat suppression and lower susceptibility artifact (qualitative scores: 4.70 vs. 4.00, 4.86% vs. 7.14%, 4.60 and 4.10, respectively). The contrast between muscle and fat and between the liver and pathologic lesions was significantly improved on the LAVA-Flex sequence. The contrast value of the fatty liver and spleen was higher than that of the liver and spleen. CONCLUSION: The LAVA-Flex sequence offers superior and more homogenous fat suppression of the abdomen than does the FSPGR sequence. The fat-only phase can be a simple and effective method of assessing fatty liver.
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Grasa Abdominal/patología , Aumento de la Imagen/métodos , Interpretación de Imagen Asistida por Computador/métodos , Grasa Intraabdominal/patología , Hepatopatías/patología , Imagen por Resonancia Magnética/métodos , Técnica de Sustracción , Adulto , Anciano , Algoritmos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadRESUMEN
Objective: This study assessed the diagnostic efficacy of combining 3.0T MRI and molybdenum target X-ray in triple-negative breast carcinoma (TNBC) and its association with the prognosis of sentinel lymph node biopsy (SLNB). Methods: The retrospective analysis included 128 patients suspected of having TNBC, who underwent 3.0T MRI and molybdenum target X-ray. Sensitivity and specificity were calculated for each imaging technique, and their combined diagnosis was evaluated using the four-table method. Consistency between the imaging techniques and pathological examination was assessed using the consistency checking method. Additionally, changes in imaging indicators were compared among patients with different prognostic indicators. Results: Among the 128 patients, 86 were diagnosed with TNBC through pathological examination. The sensitivity and specificity of 3.0T MRI for TNBC were 82.56% and 76.19%, respectively. Molybdenum target X-ray exhibited a sensitivity of 77.91% and specificity of 78.57%. The combined diagnosis of the two techniques showed a sensitivity of 90.70% and specificity of 86.36%. There was good agreement between both imaging techniques and pathological examination results. Significant differences were observed in imaging indicators based on tumor diameter, histological grade, and lymph node metastasis. Conclusion: Both 3.0T MRI and molybdenum target X-ray are valuable in diagnosing TNBC. Additionally, these imaging techniques provide prognostic information and can aid in treatment decision-making. The findings highlight the importance of 3.0T MRI and molybdenum target X-ray in improving the outcomes of patients with TNBC.