RESUMO
OBJECTIVE: The aim of the study is to explore the clinical value of the apparent diffusion coefficient (ADC) derived from the readout segmentation of long variable echo trains (RESOLVE) technique for identifying clinicopathologic features of distal rectal cancer and correlations between ADC and Ki-67 expression. METHODS: The data of 112 patients with a proven pathology of distal rectal cancer who underwent preoperative magnetic resonance imaging were retrospectively analyzed. The mean ADC value was measured using the "full-layer and center" method. Differences in ADC values and Ki-67 expression in different clinical stages, pathological types, and tumor differentiation were compared using analysis of variance. Correlations between ADC value and clinicopathologic features were assessed using Spearman correlation analysis. RESULTS: Interobserver agreement of confidence levels from 2 radiologists was excellent for ADC measurement ( k = â0.85). Patients with a lower clinical stage, well-differentiated adenocarcinomas, and a higher possibility of mucinous adenocarcinoma exhibited a positive correlation with higher ADC values, but these factors were negatively correlated with Ki-67 expression (all P < 0.05). We found that ADC value was negatively correlated with Ki-67 expression ( r = -0.62, P < 0.001). CONCLUSIONS: The ADC value generated by RESOLVE sequences was significantly associated with clinicopathologic features and Ki-67 expression in patients with distal rectal cancer in this study. Thus, the ADC value could be considered a new noninvasive imaging biomarker that could be helpful in predicting the biological properties of distal rectal cancer.
Assuntos
Imagem de Difusão por Ressonância Magnética , Antígeno Ki-67 , Neoplasias Retais , Humanos , Neoplasias Retais/diagnóstico por imagem , Neoplasias Retais/metabolismo , Neoplasias Retais/patologia , Masculino , Feminino , Pessoa de Meia-Idade , Antígeno Ki-67/metabolismo , Idoso , Imagem de Difusão por Ressonância Magnética/métodos , Estudos Retrospectivos , Adulto , Idoso de 80 Anos ou mais , Interpretação de Imagem Assistida por Computador/métodos , Reprodutibilidade dos Testes , Biomarcadores Tumorais/metabolismoRESUMO
This study compares spinal volumetric bone mineral density (vBMD) with spinal areal bone mineral density (aBMD) among young adults from 3 eastern provincial capital cities in Mainland China. A total of 416 young adults (age range: 20-40 yr) from 3 eastern provincial capital cities (Beijing, Shanghai, and Guangzhou) in Mainland China were recruited in this study. From each subject, the vBMD of the lumbar spine was measured by the Mindways quantitative computed tomography system. Moreover, the aBMD of the lumbar spine, measured by the dual-energy X-ray absorptiometry, was extracted from a previous multicenter large-scale study, and the 420 participants were matched by age, gender, height, weight, as well as geographic territory. The vBMD and the aBMD values were further compared and analyzed. Generally, the bone mineral density (BMD) results were significantly different among participants from the 3 cities (p <0.05). Specifically, both vBMD and aBMD values of participants from Beijing were significantly different from those from Guangzhou (p <0.05). Additionally, a statistically significant difference in aBMD values was also found between participants from Beijing and Shanghai (p <0.05). However, no significant differences were found between participants from Shanghai and Guangzhou in terms of the aBMD and vBMD values (p1 > 0.05 and p2 > 0.05). Interestingly, the overall mean vBMD value was 5.9% greater in women than those in men for all the 3 cities (p <0.001). This study demonstrated an overall heterogeneity in spinal BMD among young adults from 3 eastern provincial capital cities in Mainland China. Specifically, the taller and heavier young adults from the northern part of China have smaller spinal vBMD but higher spinal aBMD values than those who were shorter and lighter from the southern part of China.
Assuntos
Densidade Óssea , Vértebras Lombares/diagnóstico por imagem , Absorciometria de Fóton , Adulto , Pequim , Estatura , Índice de Massa Corporal , Peso Corporal , Feminino , Humanos , Masculino , Tomografia Computadorizada por Raios X , Adulto JovemRESUMO
The fat and bone connection is complicated, and the effect of adipose tissue on hip bone strength remains unclear. The aim of this study was to clarify the relative contribution of body fat accumulation and fat distribution to the determination of proximal femur strength in healthy postmenopausal Chinese women. This cross-sectional study enrolled 528 healthy postmenopausal women without medication history or known diseases. Total lean mass (LM), appendicular LM (ALM), percentage of lean mass (PLM), total fat mass (FM), appendicular FM (AFM), percentage of body fat (PBF), android and gynoid fat amount, android-to-gynoid fat ratio (AOI), bone mineral density (BMD), and proximal femur geometry were measured by dual energy X-ray absorptiometry. Hip structure analysis was used to compute some variables as geometric strength-related parameters by analyzing the images of the hip generated from DXA scans. Correlation analyses among anthropometrics, variables of body composition and bone mass, and geometric indices of hip bone strength were performed with stepwise linear regression analyses as well as Pearson's correlation analysis. In univariate analysis, there were significantly inverse correlations between age, years since menopause (YSM), hip BMD, and hip geometric parameters. Bone data were positively related to height, body weight, LM, ALM, FM, AFM, and PBF but negatively related to AOI and amount of android fat (all P < 0.05). AFM and AOI were significantly related to most anthropometric parameters. AFM was positively associated with height, body weight, and BMI. AFM was negatively associated with age and YSM. AOI was negatively associated with height, body weight, and BMI. AOI positively associated with age and YSM. LM, ALM, and FM had a positive relationship with anthropometric parameters (P < 0.05 for all). PLM had a negative relationship with those parameters. The correlation between LM, ALM, FM, PLM, ALM, age, and YSM was not significant. In multivariate linear regression analysis, the hip bone strength was observed to have a consistent and unchanged positive association with AFM and a negative association with AOI, whereas its association with other variables of body composition was not significant after adjusting for age, years since menopause, height, body weight, and BMI. AFM may be a positively protective effect for hip bone strength while AOI, rather than android fat, shows a strong negative association with hip bone strength after making an adjustment for confounders (age, YSM, height, body weight, and BMI) in healthy postmenopausal Chinese women. Rational weight control and AOI reduction during menopause may have vital clinical significance in decreasing postmenopausal osteoporosis.
Assuntos
Tecido Adiposo/metabolismo , Gorduras/metabolismo , Ossos Pélvicos/metabolismo , Ossos Pélvicos/fisiologia , Pós-Menopausa/metabolismo , Pós-Menopausa/fisiologia , Absorciometria de Fóton/métodos , Idoso , Idoso de 80 Anos ou mais , Antropometria/métodos , Povo Asiático , Composição Corporal/fisiologia , Índice de Massa Corporal , Peso Corporal/fisiologia , Densidade Óssea/fisiologia , Estudos Transversais , Feminino , Fêmur/metabolismo , Fêmur/fisiologia , Quadril/fisiologia , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Saúde da MulherRESUMO
PURPOSE: Non-invasive methods for predicting pathological complete response (pCR) after neoadjuvant chemoradiotherapy (nCRT) can provide distinct leverage in the management of patients with locally advanced rectal cancer (LARC). This study aimed to investigate whether including the golden-angle radial sparse parallel (GRASP) dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) perfusion parameter (Ktrans), in addition to tumor regression grading (TRG) and apparent diffusion coefficient (ADC) values, can improve the predictive ability for pCR. METHODS: Patients with LARC who underwent nCRT and subsequent surgery were included. The imaging parameters were compared between patients with and without pCR. Receiver operating characteristic (ROC) curve analysis was used to evaluate the predictive ability of these parameters for pCR. RESULTS: A total of 111 patients were included in the study. A pCR was obtained in 32 patients (28.8%). MRI-based TRG (mrTRG) showed a negative correlation with pCR (r = -0.61, P < 0.001), and the average ADC value showed a positive correlation with pCR (r = 0.62, P < 0.001). Before nCRT, Ktrans in the pCR group was significantly higher than in the non-pCR group (1.30 ± 0.24 vs. 0.88 ± 0.34, P < 0.001), but no difference was identified after nCRT. Following ROC curve analysis, the area under the curve (AUC) of mrTRG (level 1-2), average ADC value, and Ktrans value for predicting pCR were 0.738 [95% confidence interval (CI): 0.65-0.82], 0.78 (95% CI: 0.69-0.86), and 0.84 (95% CI: 0.77-0.92), respectively. The model combining the three parameters had significantly higher predictive ability for pCR (AUC: 0.94, 95% CI: 0.88-0.98). CONCLUSION: The use of a combination of the GRASP DCE-MRI Ktrans with mrTRG and ADC can lead to a better pCR predictive performance.
Assuntos
Meios de Contraste , Imageamento por Ressonância Magnética , Terapia Neoadjuvante , Neoplasias Retais , Humanos , Neoplasias Retais/terapia , Neoplasias Retais/diagnóstico por imagem , Neoplasias Retais/patologia , Masculino , Feminino , Pessoa de Meia-Idade , Terapia Neoadjuvante/métodos , Imageamento por Ressonância Magnética/métodos , Idoso , Adulto , Resultado do Tratamento , Quimiorradioterapia/métodos , Valor Preditivo dos Testes , Estudos Retrospectivos , Curva ROCRESUMO
BACKGROUND: Isolated pontine infarctions are classified as paramedian pontine infarction (PPI) and lacunar pontine infarction (LPI), usually attributed to basilar artery (BA) atherosclerosis and small vessel disease (SVD), respectively. Recently, researchers found BA atherosclerotic plaques in LPI and made the pathogenesis of LPI confusing. METHODS: We evaluated the presence and location of BA plaques with high-resolution MRI and SVD burden with presence of hypertension, leukoaraiosis and silent brain infarction. RESULTS: The prevalence of BA plaques and SVD was similar between PPI and LPI, with most plaques relevant to corresponding infarctions. Some PPI had no plaques; some LPI had no obvious SVD. CONCLUSION: SVD and BA plaques with or without lumen stenosis were both possible causes of PPI and LPI.
Assuntos
Infartos do Tronco Encefálico/patologia , Transtornos Cerebrovasculares/complicações , Arteriosclerose Intracraniana/complicações , Ponte/patologia , Insuficiência Vertebrobasilar/complicações , Idoso , Infartos do Tronco Encefálico/etiologia , Feminino , Humanos , Hipertensão/complicações , Angiografia por Ressonância Magnética , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Ponte/irrigação sanguíneaRESUMO
PURPOSE: To explore the evidence of regular alteration of bone quality in osteoporosis dynamically examined by MRS and micro-CT, comparing with histopathology. METHODS: Forty rabbits were allocated into two groups. Group A were used as sham. Group B underwent bilateral ovariectomy (OVX) combined with daily intramuscular methylprednisolone, underwent MR spectroscopy, micro-CT, and histopathology of L5 at 2, 4, 8, and 10 weeks after operation. RESULTS: Fat fraction as shown by MRS in Group B was significantly increased over the time course of osteoporosis development with significant difference between two groups at 4, 8, and 10 weeks after OVX. Continuous deterioration of cancellous bone architecture in Group B, was first detected at week 4. FF value in group B correlated with micro-CT parameters. Marrow fat as measured by MR and CT was positively correlated with both the mean density and diameter of adipocytes (both of which increased over time). CONCLUSIONS: Marrow adipogenesis occurs in synchrony with deterioration of trabecular microarchitecture.MRS may be valuable to assess the pathophysiological changes of bone marrow in osteoporosis in early stage. KEY POINTS: MRS revealed gradually increasing bone marrow fat in rabbits rendered osteoporotic. Marrow adipogenesis occurs in synchrony with deterioration of trabecular microarchitecture. Pathology revealed an early increase in number of marrow adipocytes in osteoporosis. MRS may help assess early pathophysiological bone marrow changes in osteoporosis.
Assuntos
Biomarcadores Tumorais/análise , Modelos Animais de Doenças , Espectroscopia de Ressonância Magnética/métodos , Osteoporose/diagnóstico , Tomografia Computadorizada por Raios X/veterinária , Animais , Feminino , Humanos , Osteoporose/metabolismo , Coelhos , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
OBJECTIVE: The purpose of this article is to compare the efficacy of self-expanding metallic stents and pneumatic dilation for the long-term clinical treatment of achalasia. SUBJECTS AND METHODS: Patients diagnosed with achalasia (n = 120) were allocated for treatment with pneumatic dilation (n = 30; group A) or a temporary self-expanding metallic stent with a diameter of 20 mm (n = 30; group B), 25 mm (n = 30; group C), or 30 mm (n = 30; group D). Data on clinical symptoms, complications, and long-term clinical outcomes were collected, and follow-up was performed at 6 months and at 1, 3-5, 5-8, 8-10, and more than 10 years after surgery. RESULTS: Pneumatic dilation and stent placement were technically successful in all patients. The follow-up at more than 10 years revealed that the clinical remission rate in group D (83.3%) was higher than that in groups A (0%), B (0%), and C (28.6%), and the overall cumulative clinical failure rate in group D (13%) was lower than that in groups A (76.7%), B (53.3%), and C (26.7%). Patients in group D exhibited reduced dysphagia scores and lower esophageal sphincter pressures and had normal levels of barium height and width during the follow-up periods, whereas these markers increased with time in the other groups. The duration of primary patency in group D was also longer than that in groups A, B, and C. CONCLUSION: A temporary self-expanding metallic stent with a diameter of 30 mm has superior clinical efficacy for the treatment of achalasia compared with pneumatic dilation or self-expanding metallic stents with diameters of 20 or 25 mm.
Assuntos
Acalasia Esofágica/terapia , Radiografia Intervencionista/métodos , Stents , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Distribuição de Qui-Quadrado , Criança , Meios de Contraste/administração & dosagem , Remoção de Dispositivo , Dilatação/métodos , Feminino , Seguimentos , Gastroscopia , Humanos , Iohexol/administração & dosagem , Iohexol/análogos & derivados , Masculino , Metais , Pessoa de Meia-Idade , Projetos Piloto , Estudos Prospectivos , Estatísticas não Paramétricas , Resultado do TratamentoRESUMO
BACKGROUND AND AIM: To retrospectively analyze and compare the clinical efficacy of temporary stent insertion with pneumatic dilation of the same diameter in the treatment of achalasia based on a long-term follow up. METHODS: A total of 101 treated achalasia patients were divided into a pneumatic dilation group (Group A, n = 38) and a temporary stent insertion group (Group B, n = 63). The diameter of the balloon or stent used was 30 mm. The total symptom scores (TSS) and esophageal manometry were used to assess the symptoms and lower esophageal sphincter (LES) pressure improvement. Barium swallow-esophageal studies were used to assess esophageal emptying objectively. TSS and LES pressure improvement were assessed, recorded, and compared during the regular interval follow up. RESULTS: Forty-nine pneumatic dilations and 65 stent insertions were successfully performed in all patients under fluoroscopy. Complications included pain, reflux, and bleeding, which occurred in nine (23.6%), eight (21.1%), and three (8%) patients in Group A, and in 27 (42.9%), eight (12.7%), and 10 (15.9%) patients in Group B, respectively. The stent was retained approximately 4-7 days and was retrieved via endoscope. TSS, esophageal manometry, and barium esophagram post-treatment significantly improved compared to those given pretreatment (P < 0.0001). At the end of follow up, TSS and LES pressure in Group B were 4.00 +/- 1.00 and 43.67 +/- 12.66 mmHg, compared to 10.20 +/- 0.45 (P = 0.0096) and 58.60 +/- 8.65 mmHg (P = 0.1687) in Group A. The Kaplan-Meier method revealed better symptom remission in Group B compared to Group A (log-rank test, P = 0.0212). CONCLUSION: Retrievable stent placement is more effective than the same diameter pneumatic dilation for the treatment of achalasia with a long-term follow up.
Assuntos
Cateterismo , Acalasia Esofágica/diagnóstico por imagem , Acalasia Esofágica/terapia , Stents , Adulto , Idoso , Cateterismo/efeitos adversos , Acalasia Esofágica/complicações , Acalasia Esofágica/patologia , Feminino , Seguimentos , Refluxo Gastroesofágico/etiologia , Hemorragia Gastrointestinal/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Dor/etiologia , Radiografia , Estudos Retrospectivos , Índice de Gravidade de Doença , Stents/efeitos adversos , Resultado do TratamentoRESUMO
PURPOSE: To evaluate the efficacy of added shear wave elastography (SWE) in breast screening for women with results inconsistent between mammography and conventional ultrasounds (US). MATERIALS AND METHODS: The study consisted of 282 pathologically proven breast lesions. The cancer probability from screening by mammography and conventional US were scored using Breast Imaging Reporting and Data System (BI-RADS). Elastography was used to re-evaluate inconsistent conventional US and mammography results. The diagnostic performance of conventional US, mammography, and Combined conventional clinical imaging and SWE was compared. The clinicopathological features of all breast cancer patients with inconsistent (and consistent) conventional US and mammography findings were compared. RESULT: Finally, 147 lesions were confirmed benign and 135 were malignant. The AUC of Combined conventional clinical imaging plus elastography imaging (0.870) was significantly higher than mammography (0.735, pâ<â0.001) or conventional US (0.717, pâ<â0.001) alone. Among the 135 breast cancers, 79 of the conventional US and mammography findings were consistent and 56 were inconsistent. Younger age(<50y) (pâ=â0.035), non-invasive (pâ=â0.037), smaller size (pâ=â0.002) and negative lymph node status (pâ=â0.026) were significantly associated with inconsistent findings. CONCLUSION: The added SWE in breast screening when inconsistent results from mammography and conventional US occurred is necessary and effective.
Assuntos
Neoplasias da Mama/diagnóstico por imagem , Detecção Precoce de Câncer/métodos , Técnicas de Imagem por Elasticidade/métodos , Mamografia/métodos , Ultrassonografia Mamária/métodos , Adulto , Neoplasias da Mama/patologia , Feminino , Humanos , Pessoa de Meia-IdadeRESUMO
BACKGROUND: Pulmonary injury is the main cause of death in acute paraquat (PQ) poisoning. However, whether quantitative lung computed tomography (CT) can be useful in predicting the outcome of PQ poisoning remains unknown. We aimed to identify early findings of quantitative lung CT as predictors of outcome in acute PQ poisoning. METHODS: Lung CT scanning (64-slide) and quantitative CT lesions were prospectively measured for patients after PQ intoxication within 5 days. The study outcome was mortality during 90 days follow-up. Survival curves were derived by the Kaplan-Meier method, and mortality risk factors were analyzed by the forward stepwise Cox regression analysis. RESULTS: Of 97 patients, 41 (42.3%) died. Among the eight different types of lung CT findings which appeared in the first 5-day of PQ intoxication, four ones discriminated between survivors and non-survivors including ground glass opacity (GGO), consolidation, pneumomediastinum and "no obvious lesion". With a cutoff value of 10.8%, sensitivity of 85.4% and specificity of 89.3%, GGO volume ratio is better than adopted outcome indicators in predicting mortality, such as estimated amount of PQ ingestion, plasma or urine PQ concentration, acute physiology and chronic health evaluation (APACHE) II and sequential organ failure assessment (SOFA) scores. GGO volume ratios above 10.8% were associated with increased mortality (hazard ratio, 5.82; 95% confidence interval, 4.77-7.09; P < 0.001). CONCLUSIONS: The volume ratio of GGO exceeding 10.8% is a novel, reliable and independent predictors of outcome in acute PQ poisoning.
Assuntos
Lesão Pulmonar Aguda/diagnóstico por imagem , Herbicidas/intoxicação , Pulmão/patologia , Paraquat/intoxicação , Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/mortalidade , Adulto , Feminino , Humanos , Estimativa de Kaplan-Meier , Pulmão/diagnóstico por imagem , Pulmão/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Estudos Prospectivos , Curva ROC , Tomografia Computadorizada por Raios X , Adulto JovemRESUMO
BACKGROUND: Recognizing renal vascular variants preoperatively is important in order to avoid vascular complications during surgery. This study aimed to investigate the renal vascular variants with dual-energy computed tomography (DECT) angiography to provide valuable information for surgery. METHODS: A total of 378 patients underwent DECT. The number, size, course and relationships of the renal vessels were retrospectively observed from the scans. Anomalies of renal arteries and veins were recorded and classified. Multiplanar reformations (MPR), maximum intensity projections (MIP), and volume renderings (VR) were used for analysis. RESULTS: In 378 patients (756 kidneys), renal artery variations were discovered and recorded in 123 kidneys (16.3%, 123/756) of 106 patients (28.0%, 106/378). Type IB (early branches of the only one main renal artery) and IC (accessory renal artery with only one main renal artery) were found most frequently with an incidence of 11.4% (43/378) and 14.5% (55/378). The incidence of renal artery variations in the left kidney was not statistically different than in the right kidney (12.4% vs. 11.1%). The incidence of renal vein variations was detected in 104 patients (27.5%, 104/378). The incidence of venous variants in the right kidney was higher than in the left kidney (20.1% vs. 7.4%), but left renal vein variations were more complex. Variants of the left renal vein were detected in 28 patients including type 1 (circumaortic left renal vein) in eight cases, type 2 (retroaortic left renal vein) in seven cases, type 3 (abnormal reflux) in six cases, type 4 (late venous confluence of left renal vein) in five cases, and type 5 (rare type) in two cases. The frequency of left renal vein variation associated with the left renal accessory artery was significantly higher than with early branches of the left renal artery (P = 0.037). CONCLUSIONS: The renal vascular variants are rather common and complex. DECT angiography can demonstrate the precise anatomy of the renal vessels, which is a benefit for renal transplantation or other renal operations.
Assuntos
Angiografia/métodos , Rim/irrigação sanguínea , Imagem Radiográfica a Partir de Emissão de Duplo Fóton/métodos , Veias Renais/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto JovemRESUMO
PURPOSE: Metabolic syndrome and insulin resistance have been linked to increased risk of occurrence and mortality of hepatocellular carcinoma (HCC). Recently, retinol-binding protein 4 (RBP4) was clarified as a specific serological marker of insulin resistance. The aim of this study was to determine whether serum RBP4 could be used as a potential marker for predicting prognosis in patients with HCC after curative resection. METHODS: Western immunoblotting and Enzyme-linked immunosorbent assay were used to measure the RBP4 expression in cell lines, supernatant, and serum. Serum RBP4 levels were compared with clinicopathological features and outcomes of patients with HCC. Furthermore, we investigated the impact of serum RBP4 level, serum C-peptide level, and HOMA-IR on overall survival (OS) and disease-free survival (DFS) of patients with HCC in the training cohort (156 patients with HCC), and then were validated in the validation cohort (105 patients with HCC). RESULTS: RBP4 protein overexpressed in HCC cell lines compared with normal liver cell line (P < 0.001) and correlated with metastatic potential. Serum RBP4 levels were associated with OS [hazard ratio (HR) = 2.208, P < 0.001] and DFS (HR = 1.878, P = 0.029) of patients with HCC. By multivariate analysis, the serum RBP4 level was identified as an independent factor for OS (HR = 2.170, P = 0.004) and DFS (HR = 1.769, P = 0.037) of patients with HCC. The prognostic value of serum RBP4 level was confirmed in the validation cohort. CONCLUSIONS: The serum RBP4 level is potential to be a useful prognostic factor for HCC after curative resection.
Assuntos
Carcinoma Hepatocelular/sangue , Neoplasias Hepáticas/sangue , Proteínas Plasmáticas de Ligação ao Retinol/análise , Adulto , Idoso , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/cirurgia , Linhagem Celular Tumoral , Feminino , Humanos , Fígado/química , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/cirurgia , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos RetrospectivosRESUMO
BACKGROUND: Recent studies suggest that bone marrow adipose tissue might play a role in the pathogenesis of osteoporosis. There are inconsistent findings on the relationship among marrow fat content, bone mineral density and apparent diffusion coefficient (ADC). This study aimed to prospectively explore the efficacy of MR spectroscopy (MRS) and diffusion-weighted MR imaging (DWI) in detecting vertebral marrow changes in postmenopausal women with varying bone densities. METHODS: Both MRS and DWI of the lumber spine were performed in 102 postmenopausal women (mean age, (67.3 +/- 6.5) years; range, 55 - 83 years), who underwent dual X-ray absorptiometry. Marrow fat content and ADC were compared and correlated among three groups: 24 with normal bone density, 31 with osteopenia and 47 with osteoporosis. RESULTS: Vertebral marrow fat content was significantly increased in the osteoporotic group ((65.60 +/- 7.68)%, P < 0.001) and the osteopenic group ((57.68 +/- 6.45)%, P < 0.001), when compared with the normal bone density group ((51.67 +/- 3.27)%). ADC values were significantly decreased in the osteoporotic group ((0.39 +/- 0.03) x 10(-3)mm(2)/s, P < 0.001) and in the osteopenic group ((0.42 +/- 0.02) x 10(-3)mm(2)/s, P < 0.001), when compared with the normal bone density group ((0.47 +/- 0.03) x 10(-3)mm(2)/s). The marrow fat content negatively correlated with both bone density (r = -0.731, P < 0.001) and marrow ADC (r = -0.572, P < 0.001). The bone density positively correlated with the ADC values (r = 0.802, P < 0.001). CONCLUSIONS: Postmenopausal women experience a corresponding increase in vertebral marrow fat content as the bone density decreases. Marrow fat content and ADC correlate to the bone density. MRS and DWI may indirectly assess the early bone marrow changes in postmenopausal women.
Assuntos
Densidade Óssea/fisiologia , Medula Óssea/metabolismo , Imagem de Difusão por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética/métodos , Pós-Menopausa/metabolismo , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Pessoa de Meia-IdadeRESUMO
AIM: To establish a rabbit rectal VX2 carcinoma model for the study of rectal carcinoma. METHODS: A suspension of VX2 cells was injected into the rectum wall under the guidance of X-ray fluoroscopy. Computed tomography (CT) and magnetic resonance imaging (MRI) were used to observe tumor growth and metastasis at different phases. Pathological changes and spontaneous survival time of the rabbits were recorded. RESULTS: Two weeks after VX2 cell implantation, the tumor diameter ranged 4.1-5.8 mm and the success implantation rate was 81.8%. CT scanning showed low-density foci of the tumor in the rectum wall, while enhanced CT scanning demonstrated asymmetrical intensification in tumor foci. MRI scanning showed a low signal of the tumor on T(1)-weighted imaging and a high signal of the tumor on T(2)-weighted imaging. Both types of signals were intensified with enhanced MRI. Metastases to the liver and lung could be observed 6 wk after VX2 cell implantation, and a large area of necrosis appeared in the primary tumor. The spontaneous survival time of rabbits with cachexia and multiple organ failure was about 7 wk after VX2 cell implantation. CONCLUSION: The rabbit rectal VX2 carcinoma model we established has a high stability, and can be used in the study of rectal carcinoma.