首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
Baló's concentric sclerosis (BCS) is a rare demyelinating disease considered to be a variant of multiple sclerosis. Five BCS cases were diagnosed antemortem based on their typical concentric mass patterns on MR images and based on clinical and CSF findings. Histopathologic investigation was also performed in one case. Our case report supports the concept that BCS may be a self-limited disease that is not always fatal. Characteristic MR imaging findings may allow antemortem diagnosis of BCS when performed at the onset of the disease.  相似文献   

2.
In this study, our purpose was to determine whether T2-weighted images are a useful diagnostic adjunct for lesion characterization in dynamic breast MRI. On a 1.5-T system, 205 enhancing benign and malignant breast tumors were examined. The standardized protocol consisted of a T2-weighted turbo spin echo (TSE) pulse sequence with and without spectral fat suppression (SPIR), followed by a two-dimensional dynamic series with subtraction postprocessing. In 59 cases, T2*-weighted gradient-echo images also were obtained. Two independent radiologists visually rated the lesions (101 malignant, 104 benign) as having either a low or a high signal with respect to the adjacent glandular tissue. To assess age dependency of lesion enhancement velocities and T2-TSE signal intensities, we compared the results for patients at or below the age of 50 (group A), between 40 and 50 (group B), and beyond the age of 50 (group C). In T2-weighted TSE images, breast cancers were iso- or hypointense with respect to breast parenchyma in 87% of cases, whereas fibroadenomas were hyperintense in 71%. Visual assessment of lesion appearance in T2-weighted TSE images allowed to distinguish between fibroadenomas and breast cancers, with a respective sensitivity, specificity, positive predictive value, and negative predictive value of 72%, 75%, 46%, and 90% for young patients; 94%, 66%, 78%, and 89% for the patients between 40 and 50; and 89%, 62%, 85%, and 68% for the patients over 50 years of age. No significant difference was found for the distribution of signal intensities of lesions in T2*-weighted images or in fat-suppressed images. In a contrast-enhancing breast lesion, careful analysis of T2-weighted TSE images can improve differential diagnosis. The accuracy of this criterion varies with age.  相似文献   

3.
4.

Objective  

To investigate whether the breast lesion excision system (BLES) could render formal surgery unnecessary in patients with small indeterminate breast lesions.  相似文献   

5.
6.
BACKGROUND AND PURPOSE: Though classically depicted as a continuous muscular barrier between the sublingual and submandibular spaces, the mylohyoid muscle is often discontinuous. These areas of discontinuity may contain fat, blood vessels, salivary tissue, or combinations thereof that may be mistaken both clinically and radiologically for pathologic abnormalities. We sought to demonstrate the prevalence and radiologic appearance of dehiscence of the mylohyoid muscle. METHODS: One hundred axial, contrast-enhanced CT studies of the neck, obtained over a 10-month period, were retrospectively reviewed. Inclusion criteria included 3-mm-thick slices and absence of pathologic abnormalities or surgical changes in the oral cavity. Scans were assessed for the presence and contents of mylohyoid defects such as accessory salivary tissue, defined as nonlymphoid tissue within defects in the mylohyoid, having attenuation and enhancement characteristics similar to those of orthotopic sublingual and submandibular salivary tissue. RESULTS: Mylohyoid defects were identified in 77 of 100 individuals. The deficiencies were bilateral in 67% and unilateral in 33%. Accessory salivary tissue was identified in 37 of 100. Fat and blood vessels were commonly identified within the mylohyoid defects. Sixty-one percent of the defects contained only fat. Thirty-five percent of the defects contained blood vessels. CONCLUSION: Deficiencies in the mylohyoid muscle were visible in 77% of individuals who underwent scanning. The defects may contain fat, blood vessels, salivary tissue, or all three characteristics. Accessory salivary tissue was identified in 37% of individuals who underwent scanning. Recognition of mylohyoid deficiencies and the typical appearance of accessory salivary tissue will allow accurate diagnosis of this benign, anatomic variant.  相似文献   

7.
8.
9.
Objectives  The objective of this study was to evaluate by cross-sectional imaging the prevalence and degree of cortical scalloping by small eccentric chondromas correlated with histologic diagnosis and patient history. Materials and methods  From 122 patients with histologically proven enchondromas and two patients without histology but with radiologic and clinical follow-up, 11 patients with small, eccentrically located chondromas in the long bones had cross-sectional imaging available. The lesions were evaluated for location, size, presence, and degree of cortical scalloping. The patient’s medical charts and microscope slides were reviewed for relevant clinical history, clinical management, and histology. Results  The chondromas ranged in size from 1.6 to 3.8 cm (mean 2.3 cm). Two lesions were located in the proximal femoral diaphysis, two in the distal femoral diaphysis, six in the distal femoral metaphysis, and one in the proximal tibial epimetaphysis. The lesions were curetted due to diagnostic uncertainty, continued pain, marked radiologic cortical penetration, or due to patient insistence on biopsy. All 11 lesions were benign, nine histologically, and two by stability over 4 and 7 years. The prevalence of cortical scalloping among eccentric chondromas was 100%. Cortical scalloping or occupancy ranged from 50 to 100% (mean 75%). Conclusions  All small eccentric chondromas in this study were associated with an appearance of cortical scalloping of varying degree. All curetted lesions were histologically bland without nuclear atypia. Based on the benign histology of nine lesions and lack of growth of two lesions over several years, the degree of cortical scalloping is felt to be a result of lesion location within the endosteum rather than biological activity or malignancy. This paper was presented by the first author at the 35th annual members meeting of the International Skeletal Society, New Delhi, India, October 2008.  相似文献   

10.
11.
12.
13.
14.

Objective

To develop and assess a combined reading for contrast-enhanced magnetic resonance (CE-MRI) and diffusion weighted imaging (DWI) adapted to the BI-RADS for multiparametric MRI of the breast at 3 T.

Methods

A total of 247 patients with histopathologically verified breast lesions were included in this IRB-approved prospective study. All patients underwent CE-MR and DWI at 3 T. MRIs were classified according to BI-RADS and assessed for apparent diffusion coefficient (ADC) values. A reading method that adapted ADC thresholds to the assigned BI-RADS classification was developed. Sensitivity, specificity, diagnostic accuracy and the area under the curve were calculated. BI-RADS-adapted reading was compared with previously published reading methods in the same population. Inter- and intra-reader variability was assessed.

Results

Sensitivity of BI-RADS-adapted reading was not different from the high sensitivity of CE-MRI (P?=?0.4). BI-RADS-adapted reading maximised specificity (89.4 %), which was significantly higher compared with CE-MRI (P?<?0.001). Previous reading methods did not perform as well as the BI-RADS method except for a logistic regression model. BI-RADS-adapted reading was more sensitive in non-mass-like enhancements (NMLE) and was more robust to inter- and intra-reader variability.

Conclusion

Multiparametric 3-T MRI of the breast using a BI-RADS-adapted reading is fast, simple to use and significantly improves the diagnostic accuracy of breast MRI.

Keypoints

? Multiparametric breast 3-T MRI with BI-RADS-adapted reading improves diagnostic accuracy. ? BI-RADS-adapted reading of CE-MRI and DWI is based on established reporting guidelines. ? BI-RADS-adapted reading is fast and easy to use in routine clinical practice. ? BI-RADS-adapted reading is robust to intra- and inter-reader variability.  相似文献   

15.
ObjectivesTo analyze the prevalence of tendon pathology and performance associated in pre-professional classic dancers with no history of Achilles tendon (AT) pain. Design: A cross-sectional study was conducted.ParticipantsTwenty-nine classic ballet dancers without AT pain (58 tendons) were recruited. The tendons were classified (normal, abnormal) using ultrasound imaging (USI). Cross-sectional area (CSA) and thickness of flexor hallucis longus (FHL) muscle were measured using USI. Range of movement (ROM) of the first metatarsophalangeal join, balance test, endurance test and vertical jump were measured (bilaterally) as performance variables.ResultsMore than a half (62%) of the participants had at least one abnormal tendon, with 45% of the dancers in the abnormal group having bilateral abnormalities. Dancers with AT pathology had significantly more years of dancing and number of weekly pointe hours than those with no pathology on US imaging. No significant differences between the groups were identified for the rest of the variables. Dancing years were moderately correlated with AT thickness.ConclusionsAsymptomatic classic dancers had a high incidence of tendon pathology. Increased dancing years was associated with pathology in the AT. Nevertheless, these abnormalities may not affect dance performance.  相似文献   

16.
17.
The purpose of the study was to assess whether postoperative changes in the tumour bed after intraoperative radiotherapy (IORT) with low-energy X-rays complicate the mammographic evaluation. 54 patients receiving breast-conserving surgery and IORT were compared to a control group of 48 patients with conventional breast-conserving treatment. All patients were included in routine follow-ups (≥3 years) with mammography accompanied by ultrasound. By retrospective consensus reading the mammographic changes in the tumour bed were classified as absent, low or distinct. Using the same grading it was classified whether mammographic evaluation was complicated due to postoperative changes. Focusing the yearly follow-ups within a period of four years, distinct changes were found significantly more often after IORT (52-62% vs. 7-30%). After IORT the evaluation was significantly more often distinctly complicated in each follow-up, except for year 1 (16-21% vs. 0-8%). In the IORT group the distribution of findings was nearly stable over time. In the control group it changed over time and a distinctly complicated evaluation was no longer seen in the follow-ups of years 3 and 4. Overall, further non-routine diagnostic procedures due to unclear findings in the tumour bed became necessary in 7% (IORT) vs. 8% (control group) of the patients (p=0.86). Evaluation of mammograms is complicated after IORT. In contrast to conventionally treated patients postoperative changes and difficulties of evaluation do not decrease over time. Overall, after IORT the diagnostic uncertainty does not seem to be increased in ultrasound supported mammographic follow-ups. The topic needs further evaluation with larger study samples.  相似文献   

18.
ObjectivesThe SAFE-Maintain study sought to evaluate the effect and acceptability of a physical activity counselling (PAC) session, versus a PAC session plus provision of a Fitbit (Charge HR®; PAC + F), on maintenance of physical activity levels 12 weeks following participation in a supervised exercise intervention.DesignFifty-two women with stage II + breast cancer who had recently (within the previous 7 days) completed a 12-week supervised exercise program were randomised to the PAC or PAC + F group.MethodsPhysical activity levels, including weekly minutes of total physical activity (min/week), daily step count (steps/day), and weekly minutes of moderate to vigorous physical activity (MVPA, min/week), were assessed using the Active Australia survey and Actigraph® GT3X+ accelerometers. Self-reported outcomes were assessed at baseline and 12-week follow-up, while objectively-measured outcomes were only available at 12-week follow-up.ResultsCompared with the PAC group, the PAC + F group had higher self-reported MVPA and self-reported total activity (between-group mean difference: 78.2 [95% CI = −8.3, 164.9] min/week, p < 0.01, and 171.9 [95% CI = 46.1, 297.8] min/week, p < 0.01, respectively) at 12-week follow-up. Higher objectively-assessed MVPA (p = 0.03) and steps/day (p = 0.07) at 12-week follow-up was also observed in the PAC + F group compared with the PAC group. Most (>80%) of the PAC + F group reported high levels of Fitbit use and considered the device to be beneficial for physical activity maintenance.ConclusionsFindings suggest that activity trackers show promise as an effective, feasible and acceptable approach to support physical activity maintenance following completion of a supervised exercise intervention.Trial registrationProspectively registered on the Australian and New Zealand Clinical Trials Registry (ANZCTR, Trial registration number: ACTRN12616000954426).  相似文献   

19.
IntroductionThe nucleoside analogue [18F]fluorothymidine (FLT) has been designed as a marker of cell proliferation that can be imaged in vivo by positron emission tomography. Clinical pilot studies have demonstrated decreasing FLT uptake following antiproliferative chemotherapy of breast cancer. However, the significance of posttreatment FLT uptake has not been evaluated at the cell level. The aim of this study was to investigate whether FLT uptake detects proliferation inhibition induced by docetaxel or doxorubicin treatment in an in vitro breast cancer model.MethodsBreast cancer cells (MCF-7) were treated with docetaxel or doxorubicin for 24 h at drug doses inducing 25–99% inhibition of clonogenic survival (IC25 to IC99). Cellular FLT uptake was estimated at 4 h and at 1, 3 and 5 days interval from chemotherapy. [3H]Thymidine incorporation and S-phase fraction were measured for comparison. Analysis of variance and the Bland–Altman difference plot were employed for statistical analysis.ResultsAfter treatment, FLT uptake was declined in dependence of the proliferation inhibition mediated by both chemotherapeutic agents (all P<.0001). The decrease of FLT was greater after doxorubicin treatment than after the corresponding docetaxel dose. With doxorubicin (IC99), FLT accumulation was reduced by 70% as early as 4 h after treatment. FLT uptake was closely correlated to [3H]thymidine incorporation and S-phase fraction (r=.84 to .93).ConclusionsRight after docetaxel or doxorubicin treatment, FLT uptake corresponds to the reduction of tumor cell proliferation induced. [18F]FLT appears promising for monitoring chemosensitivity in breast cancer.  相似文献   

20.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号