Vertebral body stenting. A method for repositioning and augmenting vertebral compression fractures

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.     

Prolonged thromboprophylaxis with Dalteparin during immobilization after ankle fracture surgery: a randomized placebo-controlled, double-blind study

Background Skeletal trauma and immobilization are well-known risk factors for deep vein thrombosis (DVT) and pulmonary embolism (PE). While prophylaxis against thromboembolic complications has become routine after major orthopedic surgery, whether or not prophylaxis after minor surgery and lower limb immobilization is necessary is still under debate.

Methods In a double-blind, placebo-controlled study, 272 consecutive patients were randomized to receive either thromboprophylaxis with Dalteparin (n = 136) or placebo (n = 136) for 5 weeks after ankle fracture surgery. All patients received 1 week of initial treatment with Dalteparin before randomization. A unilateral phlebography was performed when the cast was removed.

Results The overall incidence of DVT was 21% (95% CI: 13-29%) in the Dalteparin group and 28% (CI: 19- 37%) in the placebo group (risk ratio = 0.8, CI: 0.6-1.1; p = 0.3). The incidence of proximal DVTs was 4% and 3%, respectively. No major bleeding occurred.

Interpretation We found no significant difference in the incidence of DVT between the 2 treatment groups and our results do not support prolonged thromboprophylaxis. The overall incidence of DVT was high, reflecting the potential risk of PE and post-thrombotic syndrome after ankle fracture surgery. Most of the DVTs were asymptomatic, however, and were located in distal veins.     

Prompt reversal of a severe complement activation by eculizumab in a patient undergoing intentional ABO‐incompatible pancreas and kidney transplantation

Summary We describe the presumably first intentional ABO‐incompatible deceased‐donor kidney and pancreas transplantation with a severe antibody‐mediated rejection during a rebound of isoagglutinins. Rejection was successfully treated with eculizumab, which inhibits the terminal pathway of complement. Complement analysis (C3, C3d,g, and a modified assay of classical complement‐related hemolytic function) documented complement activation and confirmed that eculizumab completely blocked complement function. At 6 months, the patient had normal kidney and pancreas function, and histological evaluations revealed no evidence of sustained graft damage. This successful transplantation suggests that ABO barriers can safely be overcome without extensive preconditioning, when the complement inhibitor eculizumab is included.     

Trans-catheter aortic valve implantation--early recovery of left and preservation of right ventricular function

This study aimed to assess the early effect of trans-catheter aortic valve implantation (TAVI) on right (RV) and left ventricular (LV) function in severe aortic stenosis (AS) patients. Twenty AS patients (age 79±6 years) were examined before, one week and six weeks after TAVI using Doppler echocardiography. LV ejection fraction (EF), long-axis [mitral annular plane systolic excursion (MAPSE)] and RV long-axis [tricuspid annular plane systolic excursion (TAPSE)] function, septal radial motion were studied. Results were compared with 30 AS patients before and one week after aortic valve replacement (AVR) as well as 30 normals (reference group). Before TAVI, LVEF was reduced and E/A was higher than the reference and AVR groups (P<0.05 for all). MAPSE, TAPSE and septal motion were equally reduced in TAVI and AVR patients (P<0.05 for all). One week after the TAVI, EF increased in patients with values <50% before the procedure. In contrast, AVR resulted in reversed septal motion (P<0.001) and depressed TAPSE (P<0.001). The extent of reversed septal motion correlated with that of TAPSE in the patients group as a whole after procedures (r=0.78, P<0.001). Six weeks after TAVI, RV function remained unchanged, but LVEF increased and E/A decreased (P<0.05 for both). Thus, TAVI procedure results in significant early improvement of LV systolic and diastolic function particularly in patients with reduced EF and preserves RV systolic function.     

Advances in magnetic resonance imaging: how they are changing the management of prostate cancer

Context

Although magnetic resonance imaging (MRI) is emerging as the most commonly used imaging modality for prostate cancer (PCa) detection, treatment planning, and follow-up, its acceptance has not been uniform. Recently, great interest has been shown in multiparametric MRI, which combines anatomic T2-weighted (T2W) imaging with MR spectroscopic imaging (MRSI), dynamic contrast-enhanced MRI (DCE-MRI), and diffusion-weighted imaging (DWI).

Objective

The aim of this article is to review the current roles of these MR techniques in different aspects of PCa management: initial diagnosis, biopsy strategies, planning of radical prostatectomy (RP) and external radiation therapy (RT), and implementation of alternative focal therapies.

Evidence acquisition

The authors searched the Medline and Cochrane Library databases (primary fields: prostatic neoplasm, magnetic resonance). The search was performed without language restriction from January 2008 to November 2010.

Evidence synthesis

Initial diagnosis: The data suggest that the combination of T2W MRI and DWI or MRSI with DCE-MRI has the potential to guide biopsy to the most aggressive cancer foci in patients with previously negative biopsies, increasing the accuracy of the procedure. Transrectal MR-guided prostate biopsy can improve PCa detection, but its availability is still limited and the examination time is rather long. Planning of RP: It appears that adding MRSI, DWI, and/or DCE-MRI to T2W MRI can facilitate better preoperative characterization of cancer with regard to location, size, and relationship to prostatic and extraprostatic structures, and it may also facilitate early detection of local recurrence. Thus, use of these MR techniques may improve surgical, oncologic, and functional management. Planning of external RT and focal therapies: MR techniques have similar potential in these areas, but the published data remain very limited.

Conclusions

MRI technology is continuously evolving, and more extensive use of MRI technology in clinical trials and practice will help to improve PCa diagnosis and treatment planning.     

Thyroid Incidentaloma Detected by Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography: Practical Management Algorithm

Background  

Our aim was to design a practical algorithm for management of an increasing number of incidental findings of thyroid lesions identified by ¹⁸F-fluorodeoxyglucose positron emission tomography with computed tomography (FDG-PET/CT).     

Obstructive nephropathy in the mouse: progressive fibrosis correlates with tubulointerstitial chemokine expression and accumulation of CC chemokine receptor 2- and 5-positive leukocytes

The infiltration of leukocytes plays a major role in mediating tubulointerstitial inflammation and fibrosis in chronic renal disease. CC chemokines participate in leukocyte migration and infiltration into inflamed renal tissue. Because CC chemokine-directed leukocyte migration is mediated by target cell expression of a group of CC chemokine receptors, this study examined the expression of CC chemokines and their receptors during initiation of tubulointerstitial fibrosis after unilateral ureteral obstruction in C57BL/6 mice. Obstructed kidneys developed hydronephrosis, tubular cell damage, interstitial inflammation, and fibrosis. From days 2 to 10, a progressive interstitial influx of F4/80+ macrophages and CD3+ lymphocytes occurred (macrophages, 4-fold; lymphocytes, 20-fold at day 10, compared with contralateral control kidneys). In parallel, the number of activated fibroblast-specific protein 1+ fibroblasts and interstitial collagen IV accumulation increased from days 2 to 10. The mRNA expression of CC chemokines (predominantly monocyte chemoattractant protein-1 [MCP-1]/CCL2, RANTES/CCL5) and their receptors CCR1, CCR2, CCR5 increased progressively from days 2 to 10. By in situ hybridization, a prominent interstitial mRNA expression of MCP-1 and RANTES and their receptors CCR2 and CCR5 localized to interstitial mononuclear cell infiltrates. MCP-1 and RANTES expression was also seen in tubular epithelial cells. Fluorescence-activated cell sorter analysis of single-cell suspensions from obstructed kidneys revealed a prominent expression of CCR2 and CCR5 by infiltrating macrophages, whereas most lymphocytes expressed CCR5 only. These data demonstrate an increased expression of MCP-1/CCL2 and RANTES/CCL5 at sites of tubulointerstitial damage and progressive fibrosis during unilateral ureteral obstruction that correlates with simultaneous accumulation of interstitial macrophages and T lymphocytes expressing the respective surface receptors CCR2 and CCR5. The chemokine receptor-mediated leukocyte influx into the tubulointerstitium could offer a new potential target for therapeutic intervention in progressive renal tubulointerstitial fibrosis.     

Adverse trends in male reproductive health: we may have reached a crucial 'tipping point'

Healthy men produce an enormous number of sperms, far more than necessary for conception. However, several studies suggest that semen samples where the concentration of sperms is below 40 mill/mL may be associated with longer time to pregnancy or even subfertility, and specimens where the concentration of sperms is below 15 mill/mL may carry a high risk of infertility. Historic data from the 1940s show that the bulk of young men at that time had sperm counts far above 40 mill/mL with averages higher than 100 mill/mL. However, recent surveillance studies of young men from the general populations of young men in Northern Europe show that semen quality is much poorer. In Denmark approximately 40 percent of the men have now sperm counts below 40 mill/mL. A simulation assuming that average sperm count had declined from 100 mill/mL in 'old times' to a current level close to 40 mill/mL indicated that the first decline in average sperm number of 20-40 mill/mL might not have had much effect on pregnancy rates, as the majority of men would still have had counts far above the threshold value. However, due to the assumed decline in semen quality, the sperm counts of the majority of 20 year old European men are now so low that we may be close to the crucial tipping point of 40 mill/mL spermatozoa. Consequently, we must face the possibility of more infertile couples and lower fertility rates in the future.     

Determinants of bone mass in end-stage renal failure patients at the time of kidney transplantation

Abstract: Background:  Patients with chronic renal failure (CRF) are at high risk of renal osteodystrophy. Our study aimed to identify predictors of bone mass and cumulative fracture rate at the time of renal transplantation (RTx). This is important since the patients experience further substantial bone loss the first month post-transplant.
Material and methods:  Altogether 133 renal transplant patients were examined for bone mineral density (BMD) using dual-energy X-ray absorptiometry shortly after RTx.
Results:  The patients' Z -scores were significantly lower at the time of RTx compared to the reference population (p < 0.05), 32% were osteopenic and 11% had osteoporosis. Independent predictors of low bone mass were age (p < 0.001), female sex (p < 0.001), intact parathyroid hormone (iPTH) level (p < 0.001), former transplantation (p = 0.001) and time on hemodialysis (HD) (p = 0.005). Body mass index (BMI) (p < 0.001) and physical activity (p = 0.027) were associated with high BMD. Cumulative fracture rate (29%) was associated with physical inactivity (p = 0.003), BMI (p = 0.036) and osteopenia (p < 0.001) at the time of RTx.
Conclusion:  In a representative CRF population, BMD was reduced. Independent predictors of BMD were as for the general population, and uremia associated predictors were time on HD, previous transplantation and serum iPTH level. Fracture rate was high, and physical inactivity had the strongest association with fractures.