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21.
Purpose of the study was to demonstrate the effectiveness of expanding a fractured vertebral body by transpedicular dilatation and stenting. 7 human cadaveric vertebral bodies from L2 to L5 underwent axia compression until a vertebral burst fracture was provoked. Then, by bilateral transpedicular approach, balloon-catheters were introduced, which were armed with stents, usually used for angioplasty. The catheters were inflated with radiolucent fluid and the stents expanded under radiologic control. After expansion, the balloon was deflated and removed, the stents resting inside the vertebral body, holding their inflated shape. Then, the resulting hole was filled with an injectable biodegradable calcium-phosphate. CT-scans were performed after destruction and after expansion. Morphology before and after expansion was judged, using 3-D reconstructions. Vertebral body strength was measured before destruction and after treatment with an Instron testing machine. RESULTS: Vertebral body shape could be restored. Also impressed central parts of the bony endplate could be elevated by using a convergent approach through the pedicles. There was no collapse of the vertebral body after removing the catheter-balloons The vertebral body strength could be restored up to a physiologic level. This procedure gives new perspectives in the treatment either of osteoporotic compression or traumatic vertebral fracture. By using CT-guided technique, it could be performed by a minimally invasive approach percutaneously.  相似文献   
22.

Summary

A quantitative ultrasound (QUS) device for measurements at the proximal femur was developed and tested in vivo (Femur Ultrasound Scanner, FemUS). Hip fracture discrimination was as good as for DXA, and a high correlation with hip BMD was achieved. Our results show promise for enhanced QUS-based assessment of osteoporosis.

Introduction

Dual X-ray absorptiometry (DXA) at the femur is the best predictor of hip fractures, better than DXA measurements at other sites. Calcaneal quantitative ultrasound (QUS) can be used to estimate the general osteoporotic fracture risk, but no femoral QUS measurement has been introduced yet. We developed a QUS scanner for measurements at the femur (Femur Ultrasound Scanner, FemUS) and tested its in vivo performance.

Methods

Using the FemUS device, we obtained femoral QUS and DXA on 32 women with recent hip fractures and 30 controls. Fracture discrimination and the correlation with femur bone mineral density (BMD) were assessed.

Results

Hip fracture discrimination using the FemUS device was at least as good as with hip DXA and calcaneal QUS. Significant correlations with total hip bone mineral density were found with a correlation coefficient R 2 up to 0.72 and a residual error of about one half of a T-score in BMD.

Conclusions

QUS measurements at the proximal femur are feasible and show a good performance for hip fracture discrimination. Given the promising results, this laboratory prototype should be reengineered to a clinical applicable instrument. Our results show promise for further enhancement of QUS-based assessment of osteoporosis.  相似文献   
23.
Background Anastomotic strictures after bariatric surgery are a frequent complication that requires endoscopic management, but the optimal technique for dilation remains to be determined. The aim of this study was to evaluate the safety and efficacy of dilation with Savary–Gilliard bougies (SGB) in morbidly obese patients treated with laparoscopic Roux-en-Y gastric bypass (RYGBP). Patients and Methods Retrospective review of prospectively collected data from a series of 474 consecutive patients with laparoscopic bariatric surgery. Four-hundred twenty four of these patients (90%) underwent a laparoscopic RYGBP. A total of 24 patients were referred for anastomotic stricture dilation with SGB from January 1998 to December 2006. Results A total of 24/424 patients (6%) developed a stricture that was successfully dilated with SGB. Patients were 17 females (71%) and seven males (29%) with a mean age of 41 ± 11 years (range 24–63) and a mean BMI of 48 ± 6 (range 40–69). The time between RYGBP and the appearance of stricture-related symptoms ranged from 29 to 154 days (mean, 69 days). The mean number of dilations was 1.6 ± 0.6. The majority of patients required one (n = 11; 46%) or two (n = 12; 50%) dilations and only one patient required three dilations. During the initial dilation, a final diameter of 11 ± 1.7 mm (range 7–12.8 mm) was achieved. In all cases, there was complete resolution of symptoms. There were no complications. Conclusions Dilation with SGB is an effective, safe, and durable method for managing anastomotic strictures after laparoscopic RYGBP. Presented at the 12th World Congress of the International Federation for the Surgery of Obesity, Porto, Portugal, September 7, 2007.  相似文献   
24.
Summary   Background:A. Longo’s circular staple procedure for the treatment of haemorrhoidal disease has given rise to controversies around the globe. The circular staple procedure enables patients to return to normal activity fairly quickly and is, as far as postoperative pain is concerned, superior to conventional procedures. However, long-term results are missing and possible complications remain under scrutiny. A study of this new operative procedure goes hand in hand with a critical evaluation of all surgical procedures for the treatment of haemorrhoidal disease. Methods: We operated on noduli haemorrhoidales interni (NHI) of all degrees. By means of a circular stapler, a mucosal cuff in the distal rectum is excised and prolapsed haemorrhoids are lifted into the proximal anal canal where they regress. No further operating step is required for additional noduli haemorrhoidales externi and fissures. Marisks and skin tags are ablated separately. Surgery is performed under general anaesthesia, only in rare cases under spinal anaesthesia. Postoperative wound care is not performed. Symptoms and findings were documented in linear, analogue charts and patients were interviewed preoperatively, on the day of surgery, as well as postoperatively on the second and eighth day and after 1, 6 and 12 months. Results: We operated on 258 patients with an age of 51.2 ± 13.3 years. The average length of surgery amounted to 28 (range: 15–55) minutes, patients were admitted as in-patients for 5.7 ± 2.35 days and the median recovery-phase lasted 7 (IQR: 4–10) days. Analgesia was standardised. All patients were given intravenous Tramadolhydrochloride (100–200 mg) postoperatively. 56.3% did not require additional analgesia and the remaining patients were given Tramadol (4.5 ± 2.0 capsules of 50 mg per patient) orally. 11.0% of the patients required additional strong analgesia parenterally. 13.6% developed urinary retention that required to be catheterized. 42 patients (16.6%) developed secondary bleeding and 10 patients (3.8%) required surgery for haemostasis. Urgent bowel movement was encountered as the most common side-effect with 30.0% of the cases. Major complications did not occur. The downstaging of the haemorrhoidal degree was satisfactory. 5 patients underwent postoperative rubber-band ligation for small remaining nodules and one patient required corretive Milligan haemorrhoidectomy. Conclusions:A. Longo’s stapler resection is a reliable therapy for haemorrhoidal disease causing minimal operative strain. It leads to immediate manageability of symptoms and initiates a healing process of the pathological anatomy of haemorrhoids. Rare cases with patients experiencing considerable pain are documented. Secondary bleeding may occur, but is easily suppressed. Urgent bowel movement is the most common and lengthy side-effect, but generally speaking, patients do not consider it impairing. With rare cases, remaining internal nodules have to be corrected by rubber-band ligation. External haemorrhoids regress spontaneously. If considered impairing, marisks and skin tags are ablated separately.   相似文献   
25.
Bone is commonly affected in cancer. Cancer-induced bone disease results from the primary disease, or from therapies against the primary condition, causing bone fragility. Bone-modifying agents, such as bisphosphonates and denosumab, are efficacious in preventing and delaying cancer-related bone disease. With evidence-based care pathways, guidelines assist physicians in clinical decision-making. Of the 57 million deaths in 2008 worldwide, almost two thirds were due to non-communicable diseases, led by cardiovascular diseases and cancers. Bone is a commonly affected organ in cancer, and although the incidence of metastatic bone disease is not well defined, it is estimated that around half of patients who die from cancer in the USA each year have bone involvement. Furthermore, cancer-induced bone disease can result from the primary disease itself, either due to circulating bone resorbing substances or metastatic bone disease, such as commonly occurs with breast, lung and prostate cancer, or from therapies administered to treat the primary condition thus causing bone loss and fractures. Treatment-induced osteoporosis may occur in the setting of glucocorticoid therapy or oestrogen deprivation therapy, chemotherapy-induced ovarian failure and androgen deprivation therapy. Tumour skeletal-related events include pathologic fractures, spinal cord compression, surgery and radiotherapy to bone and may or may not include hypercalcaemia of malignancy while skeletal complication refers to pain and other symptoms. Some evidence demonstrates the efficacy of various interventions including bone-modifying agents, such as bisphosphonates and denosumab, in preventing or delaying cancer-related bone disease. The latter includes treatment of patients with metastatic skeletal lesions in general, adjuvant treatment of breast and prostate cancer in particular, and the prevention of cancer-associated bone disease. This has led to the development of guidelines by several societies and working groups to assist physicians in clinical decision making, providing them with evidence-based care pathways to prevent skeletal-related events and bone loss. The goal of this paper is to put forth an IOF position paper addressing bone diseases and cancer and summarizing the position papers of other organizations.  相似文献   
26.

Background

ADPKD is one of the most common inherited disorders, with high risk for end-stage renal disease. Numerous patients, however, have no relatives in whom this disorder is known and are unsure whether they may transmit the disease to their offsprings. The aim of this study was to evaluate whether germline mutation analysis adds substantial information to clinical symptoms for diagnosis of ADPKD in these patients.

Methods

Clinical data included renal function and presence of liver or pancreas cysts, heart valve insufficiency, intracranial aneurysms, colonic diverticles, and abdominal hernias. Family history was evaluated regarding ADPKD. Germline mutation screening of the PKD1 and PKD2 genes was performed for intragenic mutations and for large deletions.

Results

A total of 324 adult patients with ADPKD including 30 patients without a family history of ADPKD (sporadic cases) were included. PKD1 mutations were found in 24/30 and PKD2 mutations in 6 patients. Liver cysts were present in 14 patients and intracranial aneurysms in 2 patients. Fourteen patients (45%) had no extrarenal involvement. Compared to the 294 patients with familial ADPKD, the clinical characteristics and the age at the start of dialysis were similar in those with sporadic ADPKD.

Conclusion

The clinical characteristics of patients with sporadic and familial ADPKD are similar, but sporadic ADPKD is often overlooked because of the absence of a family history. Molecular genetic screening for germline mutations in both PKD1 and PKD2 genes is essential for the definitive diagnosis of ADPKD.  相似文献   
27.
28.
Bone mineral density (BMD) measured with dual energy X-ray absorptiometry (DXA) techniques is the current gold standard for osteoporotic fracture risk prediction. Quantitative ultrasound (QUS) techniques in transmission measurements are, however, increasingly recognized as an alternative approach. It is feasible to select different QUS methods, one type being optimized to assess microarchitectural properties of bone structure and another to assess BMD. Broadband ultrasonic attenuation (BUA) and ultrasonic velocity (UV) measured on the proximal human femur have been shown to be both significantly correlated with BMD. However, a great diversity of algorithms has been reported to measure the time-of-flight used to derive UV values. The purpose of this study was to determine which procedure results in the optimal BMD prediction at the proximal femur from ultrasound measurements. Thirty-eight excised human femurs were measured in transmission with a pair of focused 0.5−MHz central frequency transducers. Two-dimensional scans were performed and radiofrequency (RF) signals were recorded digitally at each scan position. BUA was estimated and eight different signal processing techniques were performed to estimate UV. For each signal-processing technique UV was compared to BMD. We show that the best prediction of BMD was obtained with signal-processing techniques taking into account only the first part of the transmitted signal (r2BMD-SOS = 0.86). Moreover, we show that a linear multiple regression using both BUA and speed of sound (SOS) and applied to site-matched regions of interest improved the accuracy of BMD predictions (r2BMD-SOS/BUA = 0.95). Our results demonstrate that selecting specific signal-processing methods for QUS variables allows optimal assessment of BMD. Correlation is sufficiently high that this specific QUS method can be considered as a good surrogate of BMD.  相似文献   
29.
The aim of this study was to determine the effect of the oral environment on the corrosion of dental alloys with different compositions, using electrochemical methods. The corrosion rates were obtained from the current-potential curves and electrochemical impedance spectroscopy (EIS). The effect of artificial saliva on the corrosion of dental alloys was dependent on alloy composition. Dissolution of the ions occurred in all tested dental alloys and the results were strongly dependent on the general alloy composition. Regarding the alloys containing nickel, the Ni-Cr and Ni-Cr-Ti alloys released 0.62 mg/L of Ni on average, while the Co-Cr dental alloy released ions between 0.01 and 0.03 mg/L of Co and Cr, respectively.The open-circuit potential stabilized at a higher level with lower deviation (standard deviation: Ni-Cr-6Ti = 32 mV/SCE and Co-Cr = 54 mV/SCE). The potenciodynamic curves of the dental alloys showed that the Ni-based dental alloy with >70 wt% of Ni had a similar curve and the Co-Cr dental alloy showed a low current density and hence a high resistance to corrosion compared with the Ni-based dental alloys. Some changes in microstructure were observed and this fact influenced the corrosion behavior for the alloys. The lower corrosion resistance also led to greater release of nickel ions to the medium. The quantity of Co ions released from the Co-Cr-Mo alloy was relatively small in the solutions. In addition, the quantity of Cr ions released into the artificial saliva from the Co-Cr alloy was lower than Cr release from the Ni-based dental alloys.  相似文献   
30.
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