RESUMO
AIM: To determine whether computed tomography (CT) texture analysis parameters can be used as quantitative biomarkers to help differentiate giant cell tumour of bones (GCTs), primary aneurysmal bone cysts (PABCs), and aneurysmal bone cysts (ABCs) secondary to giant cell tumours of bone (GABCs). MATERIALS AND METHODS: One hundred and seven patients with 63 GCTs, 31 PABCs, and 13 GABCs were analysed retrospectively. All patients underwent preoperative CT. Two radiologists independently evaluated the qualitative features of the CT images and extracted texture parameters. Patient demographics, qualitative features, and texture parameters among GCTs, PABCs, and GABCs were compared statistically. Differences in these parameters between ABCs and GCTs were also assessed. ROC curves were obtained to determine optimal parameter values. RESULTS: The best preoperative CT parameters to differentiate GCTs, PABCs, and GABCs included one qualitative feature (location around the knee) and four texture parameters (95th percentile, maximum intensity, skewness, and kurtosis). Age and three texture parameters (5th percentile, inhomogeneity, and kurtosis) enabled statistically significant differentiation between GCTs and ABCs. Combination of the above four parameters generated the largest area under the ROC curve (AUC) for the differentiation of GCTs and ABCs. CONCLUSION: CT texture analysis parameters can be used as quantitative biomarkers for preoperative differentiation among GCTs, PABCs, and GABCs.
Assuntos
Cistos Ósseos Aneurismáticos , Neoplasias Ósseas , Tumor de Células Gigantes do Osso , Humanos , Tumor de Células Gigantes do Osso/complicações , Tumor de Células Gigantes do Osso/diagnóstico por imagem , Cistos Ósseos Aneurismáticos/complicações , Cistos Ósseos Aneurismáticos/diagnóstico por imagem , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos , Biomarcadores , Neoplasias Ósseas/patologiaRESUMO
AIM: To explore the T2-mapping signal characteristics of the thigh muscles in patients with dermatomyositis/polymyositis (DM/PM) and to investigate the correlation between thigh muscle T2 values, clinical parameters, and serum creatinine kinase (CK). MATERIALS AND METHODS: Forty-two patients with DM/PM proven by diagnostic criteria were enrolled in the study along with 13 healthy control subjects. Both T2-mapping and conventional magnetic resonance imaging (MRI) images were obtained in the thigh musculature of all subjects. The T2 values of thigh muscles were compared between the DM/PM patients and control groups. Thirty-one DM/PM patients were evaluated with manual muscle testing (MMT) and serum CK levels. A Spearman correlation coefficient model was used to correlate the mean T2 values and clinical assessments. The Kruskal-Wallis test and receiver operating characteristic (ROC) curves were also utilised. p-Values <0.05 reflected statistical significance. RESULTS: The T2 value of all oedematous muscles was greater on average than that of the unaffected muscles of the DM/PM patients (p<0.05) and the muscles of healthy volunteers (p<0.05). The T2 value of unaffected muscles in DM/PM patients was also greater than that of the normal muscles in healthy volunteers (p<0.05). The area under the curves (AUCs) for T2 relaxation time values was 0.72 with respective sensitivity and specificity of 72.6% and 65.4%. The mean T2 relaxation time of the 31 patients group and the MMTs (p<0.05) was correlated without serum CK levels (p>0.05). CONCLUSION: T2 mapping is not only quantitatively used for subclinical muscle involvement in DM/PM, but also be used to demonstrate severity of damaged muscles in DM/PM.
Assuntos
Dermatomiosite/diagnóstico por imagem , Imageamento por Ressonância Magnética , Músculo Esquelético/diagnóstico por imagem , Polimiosite/diagnóstico por imagem , Coxa da Perna/diagnóstico por imagem , Adulto , Dermatomiosite/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/patologia , Polimiosite/patologia , Coxa da Perna/anatomia & histologia , Coxa da Perna/patologia , Adulto JovemRESUMO
OBJECTIVE: To assess the prevalence of anterior cruciate ligament (ACL) mucoid degeneration in patients referred for routine knee magnetic resonance (MR) imaging, and its association with age and structural joint damage. METHOD: Four independent radiologists assessed 413 consecutive knee MR examinations for the presence of a normal or ruptured ACL, or ACL mucoid degeneration. Knees with ACL mucoid degeneration were frequency matched by age, sex, and MR field strength with consecutive control knees with a normal ACL (1:2 ratio). Differences in meniscal and cartilage damage of the tibiofemoral compartments, as determined by the Whole-Organ MR Imaging Score (WORMS) system, were compared by Mann-Whitney U tests. Multivariable logistic regression analysis identified the association of ACL mucoid degeneration with severe MTFC cartilage damage (WORMS≥5). RESULTS: Patients with ACL mucoid degeneration (n = 36; 36% males; median age 55.5 years, range: 26-81) were older than patients with a normal (P < 0.001) or ruptured ACL (P < 0.001), without sex predilection (P = 0.76), and were more frequently diagnosed at 3 T (12%) compared to 1.5 T (2%). Knees with ACL mucoid degeneration had statistically significantly more medial meniscal (P < 0.001) and central and posterior medial tibiofemoral compartment (MTFC) cartilage (P < 0.001) damage compared with control knees (n = 72), but there were no differences in patients ≤50 years (P = 0.09 and 0.32, respectively). In multivariable logistic regression, severe MTFC cartilage damage (WORMS≥5) was significantly associated with ACL mucoid degeneration (odds ratio 4.09, 95% confidence interval 1.29-12.94, P = 0.016). CONCLUSION: There is a strong association between ACL mucoid degeneration and cartilage damage in the central and posterior MTFC, especially in patients >50 years.
Assuntos
Ligamento Cruzado Anterior/patologia , Cartilagem Articular/patologia , Meniscos Tibiais/patologia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Joelho/patologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Variações Dependentes do ObservadorRESUMO
AIM: To analyse the correlations between clinical and MRI sacroiliitis activity indices in ankylosing spondylitis (AS). MATERIALS AND METHODS: Sixteen normal volunteers and 52 patients were enrolled. The clinical AS activity indices included the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) score, serum high-sensitivity C-reactive protein, and erythrocyte sedimentation rate. The MRI sacroiliitis activity indices included apparent diffusion coefficient (ADC) values of bone and the Spondyloarthritis Research Consortium of Canada (SPARCC) score. RESULTS: The mean SPARCC score of the control group was 0 and of the AS group was 9.9 ± 9.1 (range 0-36). The mean ADC value of the AS group was statistically significantly higher than that of the control group (49.7 ± 20.2 × 10(-5)mm(2)/s versus 38.9 ± 5.3 × 10(-5)mm(2)/s, p < 0.05). The BASDAI score showed a statistically significant correlation with the SPARCC score (r = 0.685, p < 0.05) and with ADC values (r = 0.329, p < 0.05). ADC values correlated with the SPARCC score (r = 0.390, p < 0.05). CONCLUSION: ADC values and the SPARCC index may be useful activity indices in AS.
Assuntos
Sacroileíte/diagnóstico , Índice de Gravidade de Doença , Espondilite Anquilosante/diagnóstico , Adolescente , Adulto , Sedimentação Sanguínea , Proteína C-Reativa/análise , Estudos de Casos e Controles , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Inquéritos e Questionários , Adulto JovemRESUMO
AIM: To characterise the normal motion pattern of the pisotriquetral (PT) joint during wrist extension and flexion, as well as observer performance of measurements using four-dimensional (4D)-computed tomography (CT) acquisitions and double-oblique multiplanar reconstruction (MPR) technique in asymptomatic contralateral joints of patients with unilateral wrist pain. MATERIALS AND METHODS: In this Health Insurance Portability and Accountability Act (HIPAA)-compliant institutional review board-approved study, 4D-CT was performed on the asymptomatic contralateral wrists of 10 patients (mean age: 46 years; M/F: 6/4) for comparison to the symptomatic side. Two independent observers defined the "oblique-sagittal" plane for PT joint measurements. Measurements were obtained for the anteroposterior (AP) interval and craniocaudal (CC) excursion during the extension-flexion arc of wrist motion. RESULTS: The median (interquartile range) of the AP interval was 0.65 mm (0.55-1 mm) in extension, 1.1 mm (0.8-1.82 mm) in the neutral position, and 4.65 mm (2.07-5.87 mm) in flexion. Likewise, the median of the CC excursions in asymptomatic wrists were 0 mm in extension, 0.27 mm (0-0.37 mm) in the neutral position, and 0.28 mm (0.18-0.31 mm) in flexion. The AP interval measurements obtained at wrist flexion were larger than measurements obtained at wrist extension. There was a strong consistency in AP interval difference measurements between the two observers (ICC=0.80; p<0.01); however, CC excursion difference measurements did not reach the significance threshold between the two observers (ICC=0.40; p=0.11). CONCLUSION: PT joint kinematics in asymptomatic wrists demonstrates an increase in AP interval and CC excursion during wrist flexion. MPR techniques provide good interobserver agreements for AP interval measurements. The reported intervals for asymptomatic joints can be used as a reference for asymptomatic wrists.
Assuntos
Tomografia Computadorizada Quadridimensional , Amplitude de Movimento Articular/fisiologia , Articulação do Punho/diagnóstico por imagem , Articulação do Punho/fisiologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Valores de Referência , Reprodutibilidade dos Testes , Adulto JovemRESUMO
PURPOSE: The purpose of this study was to determine the value of dynamic pelvic floor MRI relative to standard clinical examinations in treatment decisions made by an interdisciplinary team of specialists in a center for pelvic floor dysfunction. METHODS: 60 women were referred for dynamic pelvic floor MRI by an interdisciplinary team of specialists of a pelvic floor center. All patients were clinically examined by an urologist, gynecologist, a proctological, and colorectal surgeon. The specialists assessed individually and in consensus, whether (1) MRI provides important additional information not evident by physical examination and in consensus whether (2) MRI influenced the treatment strategy and/or (3) changed management or the surgical procedure. RESULTS: MRI was rated essential to the treatment decision in 22/50 cases, leading to a treatment change in 13 cases. In 12 cases, an enterocele was diagnosed by MRI but was not detected on physical exam. In 4 cases an enterocele and in 2 cases a rectocele were suspected clinically but not confirmed by MRI. In 4 cases, MRI proved critical in assessment of rectocele size. Vaginal intussusception detected on MRI was likewise missed by gynecologic exam in 1 case. CONCLUSION: MRI allows diagnosis of clinically occult enteroceles, by comprehensively evaluating the interaction between the pelvic floor and viscera. In nearly half of cases, MRI changed management or the surgical approach relative to the clinical evaluation of an interdisciplinary team. Thus, dynamic pelvic floor MRI represents an essential component of the evaluation for pelvic floor disorders.
Assuntos
Imageamento por Ressonância Magnética , Distúrbios do Assoalho Pélvico/patologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Pessoa de Meia-Idade , Diafragma da Pelve/patologia , Reprodutibilidade dos TestesRESUMO
AIM: To evaluate the role of diffusion-weighted magnetic resonance imaging (DW-MRI) in the differentiation of hepatic abscesses from non-infected fluid collections. MATERIALS AND METHODS: In this retrospective study, 22 hepatic abscesses and 27 non-infected hepatic fluid collections were examined in 27 patients who underwent abdominal MRI including DW-MRI. Two independent observers reviewed T2-weighted + DW-MRI and T2-weighted + contrast-enhanced T1-weighted (CET1W) images in two sessions. Detection rates and confidence levels were calculated and compared using McNemar's and Wilcoxon's signed rank tests, respectively. Apparent diffusion coefficient (ADC) values of abscesses and non-infected fluid collections were compared using the t-test. Receiver operating characteristic (ROC) curves were constructed. RESULTS: There was no statistically significant difference in the accuracy of detecting abscesses using T2-weighted + DW-MRI (both observers: 21/22, 95.5%) versus T2-weighted + CET1W images (observer 1: 21/22, 95.5%; observer 2: 22/22, 100%; p < 0.01). Mean ADC values were significantly lower with abscesses versus non-infected fluid collections (0.83 ± 0.24 versus 2.25 ± 0.61 × 10(-3) mm(2)/s; p < 0.001). With ROC analysis there was good discrimination of abscess from non-infected fluid collections at a threshold ADC value of 1.36 × 10(-3) mm(2)/s. CONCLUSION: DW-MRI allows qualitative and quantitative differentiation of abscesses from non-infected fluid collections in the liver.
Assuntos
Abscesso Hepático/diagnóstico , Meios de Contraste , Diagnóstico Diferencial , Imagem de Difusão por Ressonância Magnética/métodos , Exsudatos e Transudatos , Feminino , Gadolínio DTPA , Humanos , Masculino , Pessoa de Meia-Idade , Padrões de Referência , Estudos Retrospectivos , Fatores de TempoRESUMO
PURPOSE: To determine the value of combined (18)F-FDG PET/CT with diagnostic contrast-enhanced CT (CECT) in detecting primary malignancies and metastases in patients with paraneoplastic neurological syndromes (PNS) and to compare this with CECT alone. METHODS: PET/CT scans from 66 patients with PNS were retrospectively evaluated. Two blinded readers initially reviewed the CECT portion of each PET/CT scan. In a second session 3 months later, the readers analysed the combined PET/CT scans. Findings on each study were assessed using a four-point-scale (1 normal/benign; 2 inconclusive, further diagnostic work-up may be necessary; 3 malignant; 4 inflammatory). Sensitivity and specificity for malignant findings were calculated for PET/CT and CECT. Interreader agreement was determined by calculating Cohen's kappa. Pooled data from clinical follow-up (including histopathology and follow-up imaging, median follow-up 20.0 months) served as the reference gold standard. RESULTS: Both readers classified 12 findings in ten patients (15%) as malignant on the PET/CT scans (two patients had two primary tumours). One such imaging finding (suspected thymic cancer) was false-positive (i.e. benign histology). The most common tumours were bronchial carcinoma (n = 3), lymph node metastases of gynaecological tumours (n = 3) and tonsillar carcinoma (n = 2). Three of 12 findings (25%) were not detected by CECT alone (cervical carcinoma, lymph node metastasis and tonsillar carcinoma). In a per-patient analysis, sensitivity and specificity for malignant findings were 100% and 90% for PET/CT and 78% and 88% for CECT. In 24% (reader 1) and 21% (reader 2) of the patients, the PET/CT findings were inconclusive. Of these findings, 57% (reader 1) and 56% (reader 2) were only diagnosed with PET (e.g. focal FDG uptake of the thyroid, gastrointestinal tract and ovaries). On follow-up, none of these findings corresponded to malignancy. Overall agreement between the two readers was excellent with a Cohen's kappa of 0.95 ± 0.04 (p < 0.001) for PET/CT and 0.97 ± 0.03 (p < 0.001) for CECT alone. CONCLUSION: In this cohort of patients with PNS, PET/CT exhibited improved detection of underlying malignancy versus CECT alone. While hybrid imaging produces a greater number of inconclusive findings, sensitivity is increased for the detection of head and neck and gynaecological malignancies as well as metastatic lymph node involvement.
Assuntos
Meios de Contraste , Fluordesoxiglucose F18 , Imagem Multimodal , Síndromes Paraneoplásicas do Sistema Nervoso/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada por Raios X , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Variações Dependentes do Observador , Síndromes Paraneoplásicas do Sistema Nervoso/patologia , Estudos Retrospectivos , Adulto JovemRESUMO
AIM: To evaluate the integrity of the coronary microvasculature in patients with hypertrophic cardiomyopathy (HCM) using first-pass magnetic resonance perfusion imaging. MATERIALS AND METHODS: Twenty-two patients with HCM and 13 healthy volunteers underwent cardiac magnetic resonance imaging (CMR) at rest. Imaging protocols included short axis cine, first-pass myocardial perfusion, and late-phase contrast-enhanced imaging. Left ventricular end-diastolic wall thickness (EDTH), myocardial thickening, maximal upslope of time-intensity curve (slopemax), and late myocardial gadolinium enhancement (LGE) were assessed for each myocardial segment. The differences in slopemax, myocardial thickening, and EDTH between healthy volunteers and HCM patients were evaluated as were differences among hypertrophic segments of different severities (mild, moderate, and severe hypertrophy) in a one-way analysis of variance analysis. The differences in slopemax, myocardial thickening, and EDTH between the segments with and without LGE were compared by independent-sample t-test. A Pearson correlation test was used to determine the relationships between slopemax, EDTH, and myocardial thickening. RESULTS: Slopemax was statistically significantly less in HCM patients; the degree of myocardial thickening was also significantly reduced (p < 0.001). Slopemax and the degree of thickening statistically significantly decreased with increasing degrees of myocardial hypertrophy (p < 0.05). Differences in slopemax, myocardial thickening, and EDTH were observed between segments with and without LGE (p < 0.05). Slopemax and myocardial thickening were negatively correlated with EDTH. CONCLUSION: First-pass myocardial perfusion CMR with slopemax measurements demonstrates microvascular coronary dysfunction in patients with HCM, a determination that may aid in risk stratification, therapeutic planning, and determination of prognosis for HCM.
Assuntos
Cardiomiopatia Hipertrófica/fisiopatologia , Microcirculação/fisiologia , Microvasos/fisiologia , Estudos de Casos e Controles , Eletrocardiografia , Feminino , Humanos , Angiografia por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Volume Sistólico , Disfunção Ventricular Esquerda/fisiopatologiaRESUMO
The unparalleled soft tissue contrast of magnetic resonance imaging (MRI) and the functional information obtainable with 18-F fluorodeoxyglucose positron emission tomography (FDG-PET) render MR-PET well-suited for oncological and psychiatric imaging. The lack of ionizing radiation with MRI also makes MR-PET a promising modality for oncology patients requiring frequent follow-up and pediatric patients. Lessons learned with PET computed tomography (CT) over the last few years do not directly translate to MR-PET. For example, in PET-CT the Hounsfield units derived from CT are used for attenuation correction (AC). As 511 keV photons emitted in PET examinations are attenuated by the patient's body CT data are converted directly to linear attenuation coefficients (LAC); however, proton density measured by MRI is not directly related to the radiodensity or LACs of biological tissue. Thus, direct conversion to LAC data is not possible making AC more challenging in simultaneous MRI-PET scanning. In addition to these constraints simultaneous MRI-PET acquisitions also improve on some solutions to well-known challenges of hybrid imaging techniques, such as limitations in motion correction. This article reports on initial clinical experiences with simultaneously acquired MRI-PET data, focusing on the potential benefits and limitations of MRI with respect to motion correction as well as metal and attenuation correction artefacts.
Assuntos
Algoritmos , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Imagem Multimodal/métodos , Tomografia por Emissão de Pósitrons/métodos , HumanosRESUMO
OBJECTIVE: To compare metal artefact reduction in MRI at both 3.0 T and 1.5 T using different sequence strategies. METHODS: Metal implants of stainless steel screw and plate within agarose phantoms and tissue specimens as well as three patients with implants were imaged at both 1.5 T and 3.0 T, using view angle tilting (VAT), slice encoding for metal artefact correction with VAT (SEMAC-VAT) and conventional sequence. Artefact reduction in agarose phantoms was quantitatively assessed by artefact volume measurements. Blinded reads were conducted in tissue specimen and human imaging, with respect to artefact size, distortion, blurring and overall image quality. Wilcoxon and Friedman tests for multiple comparisons and intraclass correlation coefficient (ICC) for interobserver agreement were performed with a significant level of p < 0.05. RESULTS: Compared with conventional sequences, SEMAC-VAT significantly reduced metal artefacts by 83% ± 9% for the screw and 89% ± 3% for the plate at 1.5 T; 72% ± 7% for the screw and 38% ± 13% for the plate at 3.0 T (p < 0.05). In qualitative analysis, SEMAC-VAT allowed for better visualization of tissue structures adjacent to the implants and produced better overall image quality with good interobserver agreement for both tissue specimen and human imaging (ICC = 0.80-0.99; p < 0.001). In addition, VAT also markedly reduced metal artefacts compared with conventional sequence, but was inferior to SEMAC-VAT. CONCLUSION: SEMAC-VAT and VAT techniques effectively reduce artefacts from metal implants relative to conventional imaging at both 1.5 T and 3.0 T. ADVANCES IN KNOWLEDGE: The feasibility of metal artefact reduction with SEMAC-VAT was demonstrated at 3.0-T MR. SEMAC-VAT significantly reduced metal artefacts at both 1.5 and 3.0 T. SEMAC-VAT allowed for better visualization of the tissue structures adjacent to the metal implants. SEMAC-VAT produced consistently better image quality in both tissue specimen and human imaging.
Assuntos
Artefatos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Metais , Próteses e Implantes , Animais , Feminino , Humanos , Aumento da Imagem/métodos , Masculino , Pessoa de Meia-Idade , Imagens de Fantasmas , Sensibilidade e Especificidade , Razão Sinal-Ruído , Software , Aço Inoxidável , SuínosRESUMO
PURPOSE: To evaluate the diagnostic accuracy of 3 Tesla proton MRI for the assessment of pneumonia/lung infiltrates in neutropenic patients with acute myeloid leukemia. MATERIAL AND METHODS: In a prospective study, 3 Tesla MRI was performed in 19 febrile neutropenic patients (5 women, 14 men; mean age 61 years ± 14.2; range 23-77 years). All patients underwent high-resolution CT less than 24h prior to MRI. The MRI protocol (Magnetom Tim Trio, Siemens) included a T2-weighted HASTE sequence (TE/TR: 49 ms/∞, slice thickness 6mm) and a high-resolution 3D VIBE sequence with an ultra-short TE<1 ms (TE/TR 0.8/2.9 ms, slice thickness 2mm). The VIBE sequence was examined before and after intravenous injection of 0.1 mmol/kg gadoterate meglumine (Dotarem, Guerbet). The presence of pulmonary abnormalities, their location within the lung, and lesion type (nodules, consolidations, glass opacity areas) were analyzed by one reader and compared to the findings of HRCT, which was evaluated by a second independent radiologist who served as the reference standard. The findings were compared per lobe in each patient and rated as true positive (TP) findings if all three characteristics (presence, location, and lesion type) listed above were concordant to HRCT. RESULTS: Pulmonary abnormalities were characterized by 3 Tesla MRI with a sensitivity of 82.3% and a specificity of 78.6%, resulting in an overall accuracy of 88% (NPV/PPV 66.7%/89.5%). In 51 lobes (19 of 19 patients), pulmonary abnormalities visualized by MR were judged to be concordant in their location and in the lesion type identified by both readers. In 22 lobes (11 of 19 patients), no abnormalities were present on either MR or HRCT (true negative). In 6 lobes (5 of 19 patients), ground glass opacity areas were detected on MRI but were not visible on HRCT (false positives). In 11 lobes (7 of 19 patients), MRI failed to detect ground glass opacity areas identified by HRCT. However, since the abnormalities were disseminated in these patients, accurate treatment decisions were possible in every case based on MRI. In one case MRI showed a central area of cavitation, which was not visualized by HRCT. CONCLUSION: Infectious nodules and consolidations can be detected in neutropenic patients with acute myeloid leukemia with a sufficient diagnostic accuracy by 3 Tesla MRI. Detection of ground glass opacity areas is the main limitation of 3-Tesla MRI when compared to HRCT.
Assuntos
Leucemia Mieloide Aguda/diagnóstico , Infiltração Leucêmica/patologia , Imageamento por Ressonância Magnética/métodos , Neutropenia/diagnóstico , Infiltração de Neutrófilos , Pneumonia/diagnóstico , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Feminino , Humanos , Leucemia Mieloide Aguda/complicações , Infiltração Leucêmica/complicações , Masculino , Pessoa de Meia-Idade , Neutropenia/complicações , Pneumonia/complicações , Prótons , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
PURPOSE: The purpose of this study is two-fold. First, to evaluate, whether functional rectal MRI techniques can be analyzed in a reproducible manner by different readers and second, to assess whether different clinical and pathologic T and N stages can be differentiated by functional MRI measurements. MATERIALS AND METHODS: 54 patients (38 men, 16 female; mean age 63.2 ± 12.2 years) with pathologically proven rectal cancer were included in this retrospective IRB-approved study. All patients were referred for a multi-parametric MRI protocol on a 3 Tesla MR-system, consisting of a high-resolution, axial T2 TSE sequence, DWI and perfusion imaging (plasma flow -s PFTumor) prior to any treatment. Two experienced radiologists evaluated the MRI measurements, blinded to clinical data and outcome. Inter-reader correlation and the association of functional MRI parameters with c- and p-staging were analyzed. RESULTS: The inter-reader correlation for lymph node (ρ 0.76-0.94; p<0.0002) and primary tumor (ρ 0.78-0.92; p<0.0001) apparent diffusion coefficient and plasma flow (PF) values was good to very good. PFTumor values decreased with cT stage with significant differences identified between cT2 and cT3 tumors (229 versus 107.6 ml/100ml/min; p=0.05). ADCTumor values did not differ significantly. No substantial discrepancies in lymph node ADCLn values or short axis diameter were found among cN1-3 stages, whereas PFLn values were distinct between cN1 versus cN2 stages (p=0.03). In the patients without neoadjuvant RCT no statistically significant differences in the assessed functional parameters on the basis of pathologic stage were found. CONCLUSION: This study illustrates that ADC as well as MR perfusion values can be analyzed with good interobserver agreement in patients with rectal cancer. Moreover, MR perfusion parameters may allow accurate differentiation of tumor stages. Both findings suggest that functional MRI parameters may help to discriminate T and N stages for clinical decision making.
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Carcinoma/patologia , Carcinoma/secundário , Imagem de Difusão por Ressonância Magnética/métodos , Linfonodos/patologia , Angiografia por Ressonância Magnética/métodos , Imagem Multimodal/métodos , Neoplasias Retais/patologia , Carcinoma/diagnóstico por imagem , Feminino , Humanos , Linfonodos/diagnóstico por imagem , Metástase Linfática , Masculino , Estadiamento de Neoplasias/métodos , Variações Dependentes do Observador , Radiografia , Neoplasias Retais/diagnóstico por imagem , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Método Simples-Cego , Estatística como AssuntoRESUMO
BACKGROUND AND PURPOSE: Although previous animal studies have shown structural changes in ocular hypertension such as atrophy of the LGN, such changes have not been thoroughly studied in human glaucoma patients nor correlation made with clinical stage. Our aim was to investigate prospectively LGN atrophy in patients with POAG using 3T MR imaging and correlation with the clinical stage of disease. MATERIALS AND METHODS: Twenty-six patients with known POAG and 26 age-matched healthy volunteers were included in this institutional review board-approved study. All subjects underwent imaging on a 3T MR imaging system with a PD and GM sequence. LGN height and volume were measured by 2 blinded neuroradiologists. Measurements were compared and correlated with clinical glaucoma severity as assessed by static threshold visual field parameters. RESULTS: Average maximum LGN height in patients with glaucoma on PD images was 4.36 ± 0.61 mm (right) and 4.31 ± 0.61 mm (left), significantly less (P < 10⻳) than respective measurements of 5.05 ± 0.41 and 4.99 ± 0.41 mm in volunteers. With the GM sequences, such respective measurements were also less (P < 10⻳) in patients with glaucoma (4.20 ± 0.71 mm right, 4.00 ± 0.85 mm left) versus respective measurements in volunteers (4.88 ± 0.51 mm right, 4.77 ± 0.47 mm left). Average LGN volumes in the patient group were 98.0 ± 27.2 mm³ (right) and 93.7 ± 25.8 mm³ (left) with the PD sequence versus respective measurements of 85.2 ± 27.1 and 80.5 ± 23.6 mm³ with the GM sequence. All height and volume measurements were greater in volunteers (P < 10⻳). In the patient group, both maximum height and volume of the LGN with both sequences were significantly correlated with cumulative clinical glaucoma stage (P < .05). CONCLUSIONS: MR imaging measurements of LGN height and volume are diminished in patients with glaucoma, with the extent of atrophy correlating to clinical stage, suggesting a novel imaging marker of disease severity.