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31.
The aim of this study was to simultaneously measure in vivo volumes of gray matter (GM), normal white matter (WM), abnormal white matter (aWM), and cerebro-spinal fluid (CSF), and to assess their relationship in 50 patients with relapsing-remitting multiple sclerosis (RR-MS) (age range, 21-59; mean EDSS, 2.5; mean disease duration, 9.9 years), using an unsupervised multiparametric segmentation procedure applied to brain MR studies. Tissue volumes were normalized to total intracranial volume providing corresponding fractional volumes (fGM, faWM, fWM, and fCSF), subsequently corrected for aWM-related segmentation inaccuracies and adjusted to mean patients' age according to age-related changes measured in 54 normal volunteers (NV) (age range 16-70). In MS patients aWM was 23.8 +/- 29.8 ml (range 0.4-138.8). A significant decrease in fGM was present in MS patients as compared to NV (49.5 +/- 3.2% vs 53.3 +/- 2.1%; P < 0.0001), with a corresponding increase in fCSF (13.0 +/- 3.8% vs 9.1 +/- 2.4%; P < 0.0001). No difference could be detected between the two groups for fWM (37.5 +/- 2.6% vs 37.6 +/- 2.2%). faWM correlated inversely with fGM (R = -0.434, P < 0.001 at regression analysis), and directly with fCSF (R = 0.473, P < 0.001), but not with fWM. There was a significant correlation between disease duration and EDSS, while no relationship was found between EDSS or disease duration and fractional volumes. Brain atrophy in RR-MS is mainly related to GM loss, which correlates with faWM. Both measures do not appear to significantly affect EDSS, which correlates to disease duration.  相似文献   
32.
33.
Background: Due to the high rate of donor site complications the Radial Forearm Flap (RFF) has lost ground in favor of the Antero-lateral tight flap (ALT) and other flaps. We have designed a reconstruction algorithm for reconstruction of its donor site. The goal of this study was to retrospectively evaluate the impact of this algorithm on RFF donor site complication rates.

Methods: The authors analyzed retrospectively 31 patients who underwent free radial forearm flap reconstruction between November 2009 and May 2013. Donor site complications were compared with data from patients treated before introdutction of the algorithm. Within the group were compared patients in which the flap was harvested suprafascial with those in which the flap was harvested as subfascial.

Results: Before application of the algorithm, there was a 23.3% complication rate at the RFF donor site, in our experience. After introduction of the algorithm, complication rate has dropped to 3.2%, consisting in a partial skin graft necrosis treated by local wound-care and healed without further intervention.

Conclusions: Application of the algorithm described has led to a significant reduction in RFF donor site complication rates. This demonstrates that if flap donor sites are analyzed and tailor treated in the same way as primary defects are, instead of being given secondary importance and just grafted, outcomes improve.  相似文献   

34.
Continuous intake of alcohol leads to liver cirrhosis because of imbalance of oxidative stress/antioxidative defense and chronic ‘sterile inflammation’. Hepatorenal syndrome (HRS) is the most severe complication of liver cirrhosis. The aim of our study was to assess: (1) the oxidative stress/antioxidative defense markers such as malondialdehyde (MDA), oxidative glutathione (GSH) and glutathione S-transferase (GST), (2) inflammation [C-reactive protein (CRP)], and (3) nitrate/nitrite levels (NOx) and its substrate L-arginine level. The study enrolled three groups: a group with cirrhosis and HRS (48 patients), a group with cirrhosis without HRS (32 patients), and a control group (40 healthy blood donors). All the patients with cirrhosis and HRS had type II HRS. MDA concentration was significantly higher in the groups with cirrhosis with and without HRS. Significant positive correlation was documented between the MDA level and de Ritis coefficient (AST/ALT), a marker of liver damage severity; between MDA and inflammation (CRP); between MDA and NOx concentration in the groups with cirrhosis with and without HRS. The correlation between MDA and creatinine level was significant in the group with HRS. The levels of GSH and GST were significantly lower in the groups with cirrhosis with and without HRS. The results of the study revealed that an increase in MDA and NOx concentration, along with decreased values of antioxidative defense and L-arginine, may indicate that liver damage can have an influence on progression to renal failure.  相似文献   
35.

Purpose

The use of cortical bone trajectory (CBT) pedicle screws for circumferential interbody fusion represents a viable alternative for single-level procedure with reduced invasiveness and less tissue destruction than the traditional technique. In addition, CBT screws have a potentially stronger pullout strength because of the greater amount of cortical bone intercepted. Only few series exist evaluating clinical and radiological outcomes of CBT screws.

Methods

This is a retrospective cohort study. All patients that underwent circumferential lumbar interbody fusion with CBT screws in our institution from 2014 to 2017 were reviewed. Patient demographics, clinical outcome with visual analogue scale (VAS) and Oswestry Disability Index (ODI), radiological data such as fusion, lordosis and muscle trauma, operative blood loss, hospital stay and use of fluoroscopy were evaluated.

Results

A total of 101 patients undergoing CBT-arthrodesis for degenerative lumbo-sacral disease were reviewed. Mean procedural time was 187 min. The mean operative blood loss and X-ray dose per procedure was 383 ml and 1.60 mg cm2, respectively. The mean hospital stay was 3.47 days. The mean follow-up was 18.23 months. Mean lordosis increment at the treated level was 4.2°. When the follow-up was longer than 12 months (53% of patients), fusion was obtained in 94% of cases. Mean ODI and VAS index improved with statistical significance.

Conclusions

This is to our knowledge that the largest available study regarding CBT for circumferential arthrodesis. Results underlined the safety of this technique and the promising clinical and radiological outcomes that will need a longer follow-up.

Graphical abstract

These slides can be retrieved under Electronic Supplementary material.
  相似文献   
36.

Background

The direct anterior approach (DAA) offers the potential for less soft tissue insult, improved early recovery, and reduced dislocation rates. However, complications are associated with the DAA, particularly during the learning curve. We compare the DAA learning curve experience with the posterior approach regarding in-hospital complications and revision rate.

Methods

We evaluated systemic and local in-hospital complications associated with primary unilateral cementless THAs from January 1, 2010 to December 31, 2012 in 4249 patients through a posterior approach and 289 patients through a DAA. All procedures were performed consecutively by high-volume surgeons who use a single approach in a nonselective manner. The DAA was performed by surgeon transitioning from the posterior approach, thus incorporating the learning curve. Demographics were comparable. Revision procedures were captured through a minimum 4-year follow-up. Analyses compared complication and revision rates.

Results

The DAA group demonstrated shorter length of stay, procedure time, lower blood transfusion rate, and increased discharge to home rate. Local and major systemic in-hospital complications were rare and comparable between groups. The minor systemic complication rate was significantly greater for the posterior group (10.9% posterior vs 6.2% DAA, P < .05). Revision rate was significantly greater for the posterior group (2.7% posterior vs 0.7% DAA, P < .032). The incidence of revision for dislocation was 1.5% for the posterior approach vs 0.4% for the DAA.

Conclusion

There was an increased rate of in-hospital minor systemic complications and overall revision, predominantly due to instability, after THA by the posterior approach, in comparison with the DAA.  相似文献   
37.
Bronchiolitis is the first lower respiratory tract viral infection manifesting in infants younger than 12 months of age. Our aim was to evaluate clinical and serological differences in infants with bronchiolitis from a single or from multiple viruses. Our secondary aim was to investigate differences in recurrent wheezing episodes after 12‐24‐36 months of follow‐up. We reviewed the clinical records for 486 full‐term infants hospitalized for bronchiolitis with at least one virus detected in the nasopharyngeal aspirate. In 431 (88.7%) patients one virus was detected and in 55 (11.3%) infants more than one virus was found. No differences were observed in the length of hospitalization, clinical severity score, O2 supplementation or admission to the intensive care unit. Single virus was associated with higher serum C‐reactive protein (C‐RP) than infants with multiple viruses and higher blood neutrophil counts. Respiratory syncytial virus (RSV) was the most frequently detected virus. RSV alone was associated with higher C‐RP (P = 0.007), compared to RSV coinfection. Infants with human rhinovirus (hRV) alone had higher white blood cell counts, higher blood neutrophils, and higher serum C‐RP levels than hRV co‐infection (P = 0.029, P = 0.008, P = 0.008). RSV + hRV, the most frequent co‐infection, was associated with lower neutrophil count and lower C‐RP levels (P = 0.008, P = 0.016) and less fever (P = 0.012), when comparing RSV versus hRV versus RSV + hRV. No differences were found in the frequency of recurrent wheezing between single versus multiple viruses after bronchiolitis. Our findings suggest that in infants with bronchiolitis multiple viral co‐infections can occur, without influence in the clinical severity of the disease. Infants with co‐infection seems to mount a lower inflammatory response.
  相似文献   
38.
39.
We aimed at exploring whether the prevalence of co-morbidities of chronic obstructive pulmonary disease (COPD) increases with COPD severity. Analysis of medical records of outpatients with established diagnosis of COPD was retrospectively performed. The lower limit of normality (LLN) for FEV1/FVC was applied to establish the occurrence of airway obstruction in the elderly population. The prevalence of co-morbidities was calculated, and the proportion of patients with each co-morbidity along with GOLD stages was analysed by chi-square for trend. A total of 326 (M/F: 256/70) consecutive outpatients with COPD (stage GOLD I to IV), aging 71.8 ± 9.2 years, were included in the analysis. The most frequent co-morbidities in the entire sample were systemic hypertension (64.7%), diabetes (28.5%), coronary artery disease (19.9%), arrhythmias (16.6%) and congestive heart failure (13.8%). Underweight patients were 8.0% of the sample while obese patients were 22.4%. None of the analyzed co-morbidities showed a trend towards increasing prevalence with COPD severity, except for nutritional problems. The current findings suggest that the occurrence and prevalence of co-morbidities is independent from the COPD severity, and encourage to assess co-morbidities even in the early stages of the COPD.  相似文献   
40.

Purpose

To highlight a new imaging acquisition protocol during 18F-fluorocholine PET/CT in patients with biochemical recurrence after RP.

Methods

A total of 146 patients with PSA levels between 0.2 and 1 ng/ml with negative conventional imaging who did not receive salvage treatment were prospectively enrolled. Imaging acquisition protocol included an early dynamic phase (1–8 min), a conventional whole body (10–20 min), and a late phase (30–40 min). Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were measured. Univariable and multivariable analyses were performed to identify independent predictors of positive PET/CT.

Results

The median trigger PSA was 0.6 ng/ml (IQR 0.43–0.76). Median PSA doubling time (PSA DT) was 7.91 months (IQR 4.42–11.3); median PSA velocity (PSAV) was 0.02 ng/ml per month (IQR 0.02–0.04). Overall, 18F-fluorocholine PET/CT was positive in 111 of 146 patients (76 %). Out of 111 positive examinations, 80 (72.1 %) were positive only in the early dynamic phase. Sensitivity, specificity, PPV, NPV, and accuracy were 78.9, 76.9, 97.2, 26.3, and 78.7 %, respectively. At multivariable logistic regression, trigger PSA ≥ 0.6 ng/ml [odds ratio (OR) 3.13; p = 0.001] and PSAV ≥ 0.04 ng/ml per month (OR 4.95; p = 0.004) were independent predictors of positive PET/CT. The low NPV remains the main limitation of PET/CT in this setting of patients.

Conclusions

The increased sensitivity, thanks to the early imaging acquisition protocol, makes 18F-fluorocholine PET/CT an attractive tool to detect prostate cancer recurrences in patients with a PSA level <1 ng/ml.
  相似文献   
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