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41.
The peripheral joint radiographs of 55 carefully selected patients with classic progressive systemic sclerosis (PSS) and 10 patients with CREST syndrome were reviewed in a longitudinal fashion. Thirty-three PSS and 7 CREST patients were available for followup (mean followup period 28.7 and 29.8 months, respectively). The high frequency of conventionally recognized abnormalities such as flexion contractures, digital tuft resorption, sclerodactyly, and subcutaneous calcinosis was reconfirmed. Additional hand findings included joint space narrowing (13%), juxtaarticular demineralization (4%), ankylosis (2%), marginal erosions (9%), and previously undescribed dorsal erosions (15%). All PSS findings showed progression, although isolated reversibility was noted. The CREST group showed a similar frequency and distribution of findings but with less tendency to progression. With the exception of an increased active joint count in PSS patients with erosions, computer-assisted analysis of multiple clinical and laboratory variables showed no correlation with any radiographic abnormality. These results confirm the presence of an erosive arthropathy in PSS not attributable to overlap with either rheumatoid arthritis or systemic lupus erythematosus.  相似文献   
42.
Onlay grafts made of monolithic microporous monetite bioresorbable bioceramics have the capacity to conduct bone augmentation. However, there is heterogeneity in the graft behaviour in vivo that seems to correlate with the host anatomy. In this study, we sought to investigate the metabolic activity of the regenerated bone in monolithic monetite onlays by using positron emission tomography–computed tomography (PET-CT) in rats. This information was used to optimize the design of monetite onlays with different macroporous architecture that were then fabricated using a 3D-printing technique. In vivo, bone augmentation was attempted with these customized onlays in rabbits. PET-CT findings demonstrated that bone metabolism in the calvarial bone showed higher activity in the inferior and lateral areas of the onlays. Histological observations revealed higher bone volume (up to 47%), less heterogeneity and more implant osseointegration (up to 38%) in the augmented bone with the customized monetite onlays. Our results demonstrated for the first time that it is possible to achieve osseointegration of dental implants in bone augmented with 3D-printed synthetic onlays. It was also observed that designing the macropore geometry according to the bone metabolic activity was a key parameter in increasing the volume of bone augmented within monetite onlays.  相似文献   
43.
AIM: To investigate interpretative accuracy and reporting time for radiologists performing computed tomography (CT) colonography in day-to-day non-academic clinical practice. MATERIALS AND METHODS: Thirteen radiologists from seven centres, who were reporting CT colonography in non-academic daily clinical practice, interpreted a dataset of 15 colonoscopically validated cases in a controlled environment. Ten cases had either a cancer or polyp >10mm; one case had a medium polyp and four were normal. Correct case categorization and interpretation times were compared using analysis of variance to aggregated results obtained from both experienced observers and observers recently trained using 50 cases, working in an academic environment. The effect of experience was determined using Spearman's rank correlation. RESULTS: Individual accuracy was highly variable, range 53% (95% CI 27-79%) to 93% (95% CI 68-100%). Mean accuracy overall was significantly inferior to experienced radiologists (mean 75 versus 88%, p=0.04) but not significantly different from recently trained radiologists (p=0.48). Interpretation time was not significantly different to experienced readers (mean 12.4 min versus 11.7, p=0.74), but shorter than recently trained radiologists (p=0.05). There was a significant, positive, linear correlation between prior experience and accuracy (p<0.001) with no plateau. CONCLUSION: Accuracy for sub-specialist radiologists working in a non-academic environment is, on average, equivalent to radiologists trained using 50 cases. However, there is wide variability in individual performance, which generally falls short of the average performance suggested by meta-analysis of published data. Experience improves accuracy, but alone is insufficient to determine competence.  相似文献   
44.
Halligan S  Marshall M  Taylor S  Bartram C  Bassett P  Cardwell C  Atkin W 《Clinical radiology》2003,58(12):948-54; discussion 945-7
AIM: To assess inter-observer error for the diagnosis of neoplasia on double contrast barium enema (DCBE) in the light of claims that no additional interpretative training would be needed for implementation in a national screening programme. MATERIALS AND METHODS: 10 experts, 10 consultants, and 10 experienced trainees each reported 20 DCBE studies, of which two showed cancer, three showed large polyps, four showed small polyps, and 12 were normal. Inter-observer variation was compared using odds ratios with the trainee group as reference (baseline group). RESULTS: Experts were significantly more likely to correctly identify neoplasia on DCBE than trainees. The odds of a correct diagnosis for experts were 2.79 (95% CI 2.04, 3.81) for cancer, 2.36 (1.88, 2.97) for large polyps, and 3.50 (1.98, 6.18) for small polyps. While consultants were more likely to correctly diagnose a large polyp than trainees, 1.45 (1.15, 1.84), there was no significant difference between these two groups for the correct diagnosis of either cancer, 1.24 (0.52, 2.96), or small polyps, 1.26 (0.83, 1.90). A cancer was missed by 6 (60%) experts, 9 (90%) consultants, and 8 (80%) trainees. Large polyps were missed by 4 (40%) experts, 5 (50%) consultants, and 6 (60%) trainees. There was no significant difference between any group when false positive diagnoses were considered. CONCLUSIONS: There is considerable inter-observer perceptive error for the diagnosis of neoplasia on DCBE. Experts performed significantly better than other observers but the overall standard of performance was poor, even amongst experts.  相似文献   
45.
PURPOSE: We assessed the sensitivity of preoperative lymphoscintigraphy and dynamic sentinel node biopsy for staging the inguinal region of patients with penile cancer and no palpable inguinal adenopathy. MATERIALS AND METHODS: The records of 31 patients with invasive penile cancer and nonpalpable (29) or nonsuspicious (2) inguinal lymph nodes were reviewed. Preoperatively lymphoscintigraphy plus dynamic sentinel node biopsy with (99m)technetium labeled sulfur colloid and isosulfan blue dye was performed in 21 patients and dynamic sentinel node biopsy alone with blue dye only was done in 10. All patients underwent superficial lymph node dissection regardless of preoperative lymphoscintigraphy or dynamic sentinel node biopsy findings to establish pathological nodal status. RESULTS: Six of 32 groins that showed drainage on preoperative lymphoscintigraphy had inguinal node metastasis, as did 1 of 10 that was drainage negative. The sensitivity of preoperative lymphoscintigraphy drainage for cancer detection was 86%. Using dynamic sentinel node biopsy with blue dye plus radiotracer 5 sentinel lymph nodes were positive for cancer, although 2 false-negative results were obtained. Thus, the sensitivity of dynamic sentinel node biopsy per groin for cancer detection was 71%. CONCLUSIONS: In our experience preoperative lymphoscintigraphy and dynamic sentinel node biopsy as currently performed remain insufficient for detecting occult inguinal disease. Superficial lymph node dissection remains the gold standard for detecting inguinal microscopic metastasis in select patients.  相似文献   
46.
PURPOSE: To compare the cardiovascular effects of computed tomographic (CT) colonography and conventional endoscopy in a group of patients undergoing both procedures. MATERIALS AND METHODS: A total of 144 patients underwent CT colonography followed by flexible sigmoidoscopy (40 patients) or colonoscopy (104 patients). Pulse, blood pressure, and oxygen saturation were measured before, during, and after the procedures. Forty patients also underwent continuous Holter electrocardiographic (ECG) monitoring. Periprocedural pain was assessed by using a handheld counting device. Outcome variables were assessed by using a combination of paired t testing and multilevel linear regression. RESULTS: When a spasmolytic was not used, CT colonography was associated with only a small increase in oxygen saturation (P =.03), while use of a spasmolytic caused an increase in pulse (mean increase, 19.9 beats per minute; P <.001) and diastolic blood pressure (mean increase, 5 mm Hg; P <.001). Compared with that at CT, oxygen saturation decreased significantly during and after colonoscopy and sigmoidoscopy (mean decrease after colonoscopy with sedation, 1.0%; P <.001). Systolic and diastolic blood pressure also decreased during and after colonoscopy (mean systolic decrease after colonoscopy with sedation, 16.6 mm Hg, P <.001; mean diastolic decrease after colonoscopy with sedation, 7.5 mm Hg, P <.001). Patients were 30.3 times more likely to develop bradycardia after endoscopy (95% CI: 2.65, 346; P =.006). Ventricular couplets were significantly higher at endoscopy than at CT in patients with a history of cardiac disease (odds ratio: 72.5 and 95% CI: 4.56, 1,153 at CT vs odds ratio: 14.6 and 95% CI: 0.96, 222 at endoscopy; P =.002). Patients were 1.89 times more likely to register pain during colonoscopy than during CT (95% CI: 1.06, 3.38; P =.03). CONCLUSION: CT colonography had no significant cardiovascular effect other than spasmolytic-induced tachycardia. Endoscopy-and colonoscopy in particular-causes cardiovascular effects that are largely related to sedation. CT colonography is less painful than colonoscopy and is comparable to flexible sigmoidoscopy.  相似文献   
47.
48.
Cryotherapy is a therapeutic modality frequently used in the treatment of athletic injuries. In very rare circumstances, inappropriate use in some individuals can lead to nerve injury resulting in temporary or permanent disability of the athlete. Six cases of cold-induced peripheral nerve injury from 1988 to 1991 at the Sports Medicine Center at Duke University are reported. Although disability can be severe and can render an athlete unable to compete for several months, each of these cases resolved spontaneously. Whereas the application of this modality is typically quite safe and beneficial, clinicians must be aware of the location of major peripheral nerves, the thickness of the overlying subcutaneous fat, the method of application (with inherent or additional compression), the duration of tissue cooling, and the possible cryotherapy sensibility of some individuals.  相似文献   
49.
The purpose of this study was to determine if greater z-axis tumour coverage improves the reproducibility of quantitative colorectal cancer perfusion measurements using CT. A 65 s perfusion study was acquired following intravenous contrast administration in 10 patients with proven colorectal cancer using a four-detector row scanner. This was repeated within 48 h using identical technical parameters to allow reproducibility assessment. Quantitative tumour blood volume, blood flow, mean transit time and permeability measurements were determined using commercially available software (Perfusion 3.0; GE Healthcare, Waukesha, WI) for data obtained from a 5 mm z-axis tumour coverage, and from a 20 mm z-axis tumour coverage. Measurement reproducibility was assessed using Bland-Altman statistics, for a 5 mm z-axis tumour coverage, and 20 mm z-axis tumour coverage, respectively. The mean difference (95% limits of agreement) for blood volume, blood flow, mean transit time and permeability were 0.04 (-2.50 to +2.43) ml/100 g tissue; +8.80 (-50.5 to +68.0) ml/100 g tissue/min; -0.99 (-8.19 to +6.20) seconds; and +1.20 (-5.42 to +7.83) ml/100 g tissue/min, respectively, for a 5 mm coverage, and -0.04 (-2.61 to +2.53) ml/100 g tissue; +7.40 (-50.3 to +65.0) ml/100 g tissue/min; -2.46 (-12.61 to +7.69) seconds; and -0.23 (-8.31 to +7.85) ml/100 g tissue/min, respectively, for a 20 mm coverage, indicating similar levels of agreement. In conclusion, increasing z-axis coverage does not improve reproducibility of quantitative colorectal cancer perfusion measurements.  相似文献   
50.
Brain networks are increasingly characterized at different scales, including summary statistics, community connectivity, and individual edges. While research relating brain networks to behavioral measurements has yielded many insights into brain‐phenotype relationships, common analytical approaches only consider network information at a single scale. Here, we designed, implemented, and deployed Multi‐Scale Network Regression (MSNR), a penalized multivariate approach for modeling brain networks that explicitly respects both edge‐ and community‐level information by assuming a low rank and sparse structure, both encouraging less complex and more interpretable modeling. Capitalizing on a large neuroimaging cohort (n = 1, 051) , we demonstrate that MSNR recapitulates interpretable and statistically significant connectivity patterns associated with brain development, sex differences, and motion‐related artifacts. Compared to single‐scale methods, MSNR achieves a balance between prediction performance and model complexity, with improved interpretability. Together, by jointly exploiting both edge‐ and community‐level information, MSNR has the potential to yield novel insights into brain‐behavior relationships.  相似文献   
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