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101.

Background

Adverse reaction to metal debris is a relatively recently described and often a silent complication of metal-on-metal (MOM) total hip replacements (THR). The Norfolk & Norwich University Hospital has been performing metal artefact reduction (MARS) MRI for 8 years in a variety of different types of MOM THR.

Questions/purposes

The aims of this review are to describe the experience of using MARS MRI in Norwich and to compare our experience with that published by other groups.

Methods

A MEDLINE keyword search was performed for studies including MRI in MOM THR. Relevant publications were reviewed and compared with published data from the Norfolk & Norwich University Hospital. The similarities and differences between these data were compared and possible explanations for these discussed.

Results

MARS MRI appears to be the most useful tool for diagnosing, staging and monitoring adverse reactions to metal debris (ARMD). There appears to be no clinically useful association between clinical and serological markers of disease and the severity of MR findings. Although severe early ARMD is associated with significant morbidity, mild disease is often stable for years. If patients with normal initial MR examinations develop ARMD, this usually occurs 7 years. A 1-year interval between MRI examinations is reasonable in asymptomatic patients.

Conclusions

There is a general international consensus that ARMD is prevalent in symptomatic and asymptomatic patients with MOM THR and that while appearances vary with the type of prosthesis, there are characteristic features that make MARS MRI essential for diagnosis, staging and surveillance of the disease.  相似文献   
102.

Background

Ankylosing spondylitis (AS) is a chronic inflammatory disease with multiple articular and para-articular involvement that has a predilection for the axial skeleton. In spite of its high prevalence, ankylosis secondary to AS is a rare condition.

Case report

A 31-year-old male diagnosed with AS was referred for computed tomography (CT) of the temporomandibular joint (TMJ) due to severe mouth opening limitation. The patient had a 16-year medical history of AS and sought assistance due to TMJ pain and incapacity to open his mouth.

Results

Previous bony scintigraphy revealed involvement of the spine, sacroiliac joints, right knee, and left TMJ. Magnetic resonance imaging revealed erosion of the left condyle and posterior slope of the articular eminence, and a mass of heterogeneous signal intensity between these structures. The left condyle also presented sclerosis/edema of the bone marrow and the disk could not be identified. Sagittal and coronal CT images showed moderate alterations of the TMJ on the right side. On the left side, the images displayed markedly eroded condyle and mandibular fossa, and a bony mass resulting in ankylosis of the osseous components of the joint.

Conclusion

TMJ ankylosis in AS patients is rare and very few reports have presented imaging features of the condition through advanced diagnostic techniques.  相似文献   
103.
Adverse childhood events (ACE’s) have been empirically related to a wide range of negative health and mental health outcomes. However, not all individuals who experience ACE’s follow a trajectory of poor outcomes, and not all individuals perceive the impact of ACE’s as necessarily negative. The purpose of this study was to investigate positive and negative affect as predictors of adults’ ratings of both the childhood and adult impact of their childhood adversity. Self-report data on ACE experiences, including number, severity, and ‘impact’ were collected from 158 community members recruited on the basis of having adverse childhood experiences. Results indicated that, regardless of event severity and number of different types of adverse events experienced, high levels of negative affect were the strongest predictor of whether the adult impact of the adverse childhood events was rated as negative. All individuals rated the childhood impact of events the same. Implications are discussed.  相似文献   
104.
The aim of this study was to compare data on design and fabrication methods of removable partial dentures (RPDs) in two major cities in Greece. A questionnaire was sent to 150 randomly selected dental technicians. The participation rate was 79.3%. The anterior palatal strap, the lingual bar, and the Roach-type clasp arm designs were preferred. Half of the RPDs fabricated were retained using precision attachments. Differences between the two cities were observed in types of major maxillary connectors used, types of attachments and impression materials used, as well as the design of distal-extension RPDs. Postdoctoral education was found to have an impact on RPD fabrication. Despite the differences observed, design and fabrication of RPDs followed commonly used principles.  相似文献   
105.
Neurological Sciences - Sleep is a fundamental physiological process necessary for efficient cognitive functioning especially in relation to memory consolidation and executive functions, such as...  相似文献   
106.

Purpose

The purpose of our study was 1) to evaluate the diagnostic performance of 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT), 2) to assess the impact of FDG PET/CT on treatment decision-making, and 3) to estimate the prognostic value of FDG PET/CT in the restaging process among patients with renal cell carcinoma (RCC).

Methods

From the FDG PET/CT databases of San Raffaele Hospital in Milan, Italy, and the Veneto Institute of Oncology in Padua, Italy, we selected 104 patients with a certain diagnosis of RCC after surgery, and for whom at least 24 months of post-surgical FDG PET/CT, clinical, and instrumental follow-up data was available. The sensitivity and specificity of FDG PET/CT were assessed by histology and/or other imaging as standard of reference. Progression-free survival (PFS) and overall survival (OS) were computed using the Kaplan–Meier method. Univariate and multivariate Cox proportional hazards models were used to identify predictors of outcome.

Results

FDG PET/CT resulted in a positive diagnosis in 58 patients and a negative diagnosis in 46 patients. Sensitivity and specificity were 74 % and 80 %, respectively. FDG PET/CT findings influenced therapeutic management in 45/104 cases (43 %). After a median follow-up period of 37 months (± standard deviation 12.9), 51 (49 %) patients had recurrence of disease, and 26 (25 %) had died. In analysis of OS, positive versus negative FDG PET/CT was associated with worse cumulative survival rates over a 5-year period (19 % vs. 69 %, respectively; p <0.05). Similarly, a positive FDG PET/CT correlated with a lower 3-year PFS rate. In addition, univariate and multivariate analysis revealed that a positive scan, alone or in combination with disease stage III–IV or nuclear grading 3–4, was associated with high risk of progression (multivariate analysis = hazard ratios [HRs] of 4.01, 3.7, and 2.8, respectively; all p?<?0.05).

Conclusions

FDG PET/CT is a valuable tool both in treatment decision-making and for predicting survival and progression in patients affected by RCC.
  相似文献   
107.
108.
109.
Objective: The purpose of this retrospective observational cohort study was to determine the impact of certain risk factors on fetal loss, after mid-trimester amniocentesis.

Material and methods: Six thousand seven-hundred and fifty-two (6752) consecutive amniocenteses with known pregnancy outcome performed during a 7-year period (2004–2010) were included in this study. Different maternal-, fetal- and procedure-related factors were evaluated in this study.

Results: During this 7-year period, 6752 cases who underwent amniocentesis, with complete data available were evaluated for the outcome and risk factors mentioned. Total fetal loss rate (FLR) up to the 24th week was 1.19%. Risk factors associated with increased risk of fetal loss after amniocentesis were maternal age (OR:2.0), vaginal spotting (OR:2.2) and serious bleeding (OR:3.5) during pregnancy, history of 2nd trimester termination of pregnancy (OR:4.0), history of more than three spontaneous (OR:3.0) or surgical first trimester abortions (OR:2.1), fibromas (OR:3.0) and stained amniotic fluid (OR:6.1).

Conclusions: Amniocentesis is a safe-invasive procedure for prenatal diagnosis with total FLR of 1.19% in our institution during the study period. The present study has emphasized the significance of certain risk factors for adverse outcome and therefore the need to individualize the risk.  相似文献   
110.
The Jefferson Scale of Empathy (JSE) is a broadly used instrument developed to measure empathy in the context of health professions education and patient care. Evidence in support of psychometrics of the JSE has been reported in health professions students and practitioners with the exception of osteopathic medical students. This study was designed to examine measurement properties, underlying components, and latent variable structure of the JSE in a nationwide sample of first-year matriculants at U.S. colleges of osteopathic medicine, and to develop a national norm table for the assessment of JSE scores. A web-based survey was administered at the beginning of the 2017–2018 academic year which included the JSE, a scale to detect “good impression” responses, and demographic/background information. Usable surveys were received from 6009 students enrolled in 41 college campuses (median response rate?=?92%). The JSE mean score and standard deviation for the sample were 116.54 and 10.85, respectively. Item-total score correlations were positive and statistically significant (p?<?0.01), and Cronbach α?=?0.82. Significant gender differences were observed on the JSE scores in favor of women. Also, significant differences were found on item scores between top and bottom third scorers on the JSE. Three factors of Perspective Taking, Compassionate Care, and Walking in Patient’s Shoes emerged in an exploratory factor analysis by using half of the sample. Results of confirmatory factor analysis with another half of the sample confirmed the 3-factor model. We also developed a national norm table which is the first to assess students’ JSE scores against national data.  相似文献   
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