M. Libicher

Treatment of Painful Vertebral Fractures by Kyphoplasty in Patients With Primary Osteoporosis: A Prospective Nonrandomized Controlled Study

This study investigates the effects of kyphoplasty on pain and mobility in patients with osteoporosis and painful vertebral fractures compared with conventional medical management.

Reduction of pain and fracture incidence after kyphoplasty: 1-year outcomes of a prospective controlled trial of patients with primary osteoporosis

Previously, we reported significantly reduced pain and improved mobility persisting for 6 months after kyphoplasty of chronically painful osteoporotic vertebral fractures in the first prospective controlled trial. Since improvement of spinal biomechanics by restoration of vertebral morphology may affect the incidence of fracture, long-term clinical benefit and thereby cost-effectiveness, here we extend our previous work to assess occurrence of new vertebral fractures and clinical parameters 1 year after kyphoplasty compared with a conservatively treated control group. Sixty patients with osteoporotic vertebral fractures due to primary osteoporosis were included: 40 patients were treated with kyphoplasty, 20 served as controls. All patients received standard medical treatment. Morphological characteristics, new vertebral fractures, pain (visual analog scale), physical function [European Vertebral Osteoporosis Study (EVOS) score] (range 0–100 each) and back-pain-related doctors’ visits were re-assessed 12 months after kyphoplasty. There were significantly fewer patients with new vertebral fractures of the thoracic and lumbar spine, after 12-months, in the kyphoplasty group than in the control group (P=0.0084). Pain scores improved from 26.2 to 44.4 in the kyphoplasty group and changed from 33.6 to 34.3 in the control group (P=0.008). Kyphoplasty treated patients required a mean of 5.3 back-pain-related doctors’ visits per patient compared with 11.6 in the control group during 12 months follow-up (P=0.006). Kyphoplasty as an addition to medical treatment and when performed in appropriately selected patients by an interdisciplinary team persistently improves pain and reduces occurrence of new vertebral fractures and healthcare utilization for at least 12 months in individuals with primary osteoporosis.

Evaluation of angiogenesis and perfusion of bone marrow lesions: Role of semiquantitative and quantitative dynamic MRI

Magnetic resonance imaging (MRI) is a noninvasive technique that complements computed tomography (CT), conventional X‐ray, and bone marrow biopsies by sampling a large volume of musculoskeletal bone and providing information that aids the diagnosis, staging, and follow‐up of various lesions. Although less sensitive to the mineral components of bones, the MRI appearance of physiologic bone marrow is mainly a reflection of the relative amounts of red marrow, yellow marrow, and trabecular bone. Therefore, use of T1‐and T2‐weighted MR sequences with or without fat suppression currently remains the most common approach to musculoskeletal bone lesion imaging. An additional imaging strategy to characterize various bone lesions is the application of contrast‐enhanced dynamic MRI. This article examines semiquantitative and quantitative dynamic imaging, evaluation, and postprocessing techniques in various benign and malignant musculoskeletal lesions. Practical guidelines for performing a dynamic contrast‐enhanced MR examination are proposed. J. Magn. Reson. Imaging 1999; 10:286–294.

Calcium-phosphate and polymethylmethacrylate cement in long-term outcome after kyphoplasty of painful osteoporotic vertebral fractures.

Study Design. A comparative prospective trial evaluating 3-year outcome. Objective. To compare clinical and morphologic outcomes as well as follow-up fractures after kyphoplasty of painful osteoporotic vertebral fractures with calcium-phosphate (CaP) cement (group 1) and with polymethylmethacrylate (PMMA)-cement (group 2). Summary of Background Data. CaP cements seem to be an alternative material for usage in kyphoplasty of vertebral fractures. CaP cements are biodegradable and replaceable by newly formed bone after implantation. Concerns have been raised with regard to the stability of resorbable CaP-cements after implantation into vertebrae post kyphoplasty. Calcibon is a possible CaP cement, which exhibited adequate stability in short-term observations. Materials and Methods. Kyphoplasty was performed in 40 consecutive patients with primary osteoporosis and painful vertebral fractures, 20 received CaP-cement, 20 were treated with PMMA-cement. All patients received a pharmacological antiosteoporosis treatment (1000 mg calcium, 1000 IU vitamin D3, and oral aminobisphosphonate), pain medication, and physiotherapy. Pain (visual analog scale [VAS]; range, 0–100), mobility (EVOS-score; range, 0–100) and radiomorphologic measurements were assessed at baseline and after 6, 12, and 36 months. Results. There were no statistically significant differences between the CaP and PMMA-cement group regarding VAS-scores, EVOS-scores, or height-restoration at any time point. Furthermore, there was no significant difference in the occurrence of vertebral follow-up fractures between both groups during the 3-year follow-up period. Conclusion. CaP cement, e.g., Calcibon, is as effective and safe as conventional PMMA-cement with regard to immediate and sustained pain reduction and improvement of mobility after kyphoplasty of patients with painful osteoporotic vertebral fractures. CaP cement has the potential of being resorbed and replaced by newly formed bone tissue; thus, it seems to be a promising alternative for PMMA also in younger patients with painful vertebral fractures.

MR-relaxometry of myocardial tissue : Significant elevation of T1 and T2 relaxation times in cardiac amyloidosis

Objective:This study evaluates if MR-relaxometry of myocardial tissue reveals significant differences in cardiac amyloidosis (CA) compared with patients with systemic amyloidosis but without cardiac involvement (NCA) and a healthy control group. Therefore, we measured T1 and T2 relaxation times (RT) of the left ventricular myocardium with magnetic resonance imaging at 1.5 T. Material and Methods:Nineteen consecutive patients (14 males, 5 females; mean age, 59 ± 6.1 years) with histologically proven CA were evaluated. T1-RT and T2-RT were measured by using a saturation-recovery TurboFLASH sequence and a HASTE sequence, respectively. Additionally, morphologic and functional data were acquired. Results were compared with patients with systemic amyloidosis but without cardiac involvement (NCA; 5 males, 4 females, 48.9 ± 15.4 years) and 10 healthy, age-matched control subjects (5 males, 5 females, 60.4 ± 6.4 years). Results:MR-relaxometry revealed a significant elevation of T1-RT of the left ventricular myocardium in CA-patients compared with that in NCA-patients and the age-matched control group [mean ± SD (95% CI) 1340 ± 81 (1303–1376) msec, 1213 ± 79 (1160–1266) msec, 1146 ± 71 (1096–1196) msec, respectively; CA vs. control, P < 0.0001; CA vs. NCA:, P < 0.0003; NCA vs. control, P = 0.07]. T2-RT showed a marginal but significant increase in CA-patients compared with NCA-patients and the control group [mean ± SD (95% CI) 81 ± 12 (76–86) msec, 71 ± 11 (64–79) msec, 72 ± 9 (65–79) msec, respectively; CA vs. control, P = 0.04; CA vs. NCA, P = 0.04; NCA vs. control, P = 0.91]. T1-RT was best suited to discriminate between the groups as shown by logistic regression. A cut-off value of ≥1273 milliseconds for T1-RT was defined using receiver–operator characteristics-analysis to establish the diagnosis of CA with a high sensitivity (84%) and specificity (>89%). Conclusions:Measurement of T1 and T2 RT is a novel approach for noninvasive evaluation of CA. MR-relaxometry might improve diagnostic reliability of magnetic resonance imaging for evaluation of cardiac involvement in systemic amyloidosis.

Early changes in experimental osteoarthritis using the Pond-Nuki dog model: technical procedure and initial results of in vivo MR imaging

The purpose of this study was to prove the feasibility of combining in vivo MR imaging with the Pond-Nuki animal model for the evaluation of osteoarthritis. In an experimental study, 24 beagle dogs underwent transection of the anterior cruciate ligament of the left leg (modified Pond-Nuki model). The dogs were randomly assigned into four groups and examined by MRI after 6, 12, 24 and 48 weeks. MR imaging of both knees was performed under general anesthesia with the contralateral joint serving as control. In group 1 (6 weeks postoperatively), the first sign detected on MRI was subchondral bone marrow edema in the posteromedial tibia. After 12 weeks, erosion of the posteromedial tibial cartilage could be observed, followed by meniscus degeneration and osteophytosis after 24 and 48 weeks. The contralateral knee joint showed transient joint effusion, but no significant signs of internal derangement (P<0.001). By combining in vivo MR imaging with the Pond-Nuki model, it is possible to detect early signs of osteoarthritis. The first sign was posteromedial subchondral bone marrow edema in the tibia followed by progressive cartilage degeneration and joint derangement. The in vivo model therefore seems to be suitable for longitudinal studies or monitoring the therapeutic effects of osteoarthritis.

Three-year Outcomes after Kyphoplasty in Patients with Osteoporosis with Painful Vertebral Fractures

PURPOSE Kyphoplasty immediately improves pain and mobility in patients with painful osteoporotic vertebral fractures, but long-term clinical outcomes are still unclear. This controlled trial evaluates pain, mobility and fracture incidence 3 years after kyphoplasty. MATERIALS AND METHODS Kyphoplasty was performed in 40 patients with painful osteoporotic vertebral fractures; 20 patients who were selected for kyphoplasty but chose not to undergo the procedure served as controls. All patients received pharmacologic antiosteoporosis treatment, pain medication, and physiotherapy. Pain (visual analog scale of 0-100), mobility (European Vertebral Osteoporosis Study questionnaire score of 0-100), and incident vertebral fractures were assessed at baseline, postprocedurally, and after 12 and 36 months. RESULTS Pain score improved after kyphoplasty from 73.8 to 55.9 (immediately after kyphoplasty), 55.6 (12 months), and 54.0 (36 months; P < .001). Pain score in the control group changed from 66.4 to 65.7 at 12 months and 64.0 at 36 months (P = .521). The pain score of the kyphoplasty group was significantly improved versus controls after 36 months (P = .023). Mobility score improved after kyphoplasty from 43.8 to 54.2 (immediately after kyphoplasty), 54.5 (12 months), and 54.8 (36 months; P = .0008) and remained increased (P = .308) compared with controls (39.8 immediately after kyphoplasty, 44.3 at 12 months, and 43.6 at 36 months). The incidence of new vertebral fractures after kyphoplasty was significantly reduced versus controls after 3 years (P = .0341). CONCLUSIONS Kyphoplasty reduces pain and improves mobility as long as 3 years after the procedure. The long-term risk of new vertebral fractures after kyphoplasty of chronically painful vertebral fractures is reduced versus controls.

Gastrointestinal stromal tumours and their response to treatment with the tyrosine kinase inhibitor imatinib.

Gastrointestinal stromal tumours (GISTs), the most common mesenchymal tumours of the digestive tract, are largely resistant to chemo- and radiotherapy. They are currently defined by their overexpression of the KIT receptor tyrosine kinase (CD117), a member of the family of receptor tyrosine kinases (RTKs), and exhibit KIT mutations in more than 85% of cases. Additionally, in more than one-third of KIT wild-type GISTs, mutations of platelet-derived growth factor receptor α (PDGF-Rα), which also belongs to the family of RTKs, were recently found. Since these data indicate that uncontrolled RTK signalling may be implicated in the pathogenesis of GISTs, RTKs and the activated downstream signalling cascades are attractive targets in the therapy of these tumours. Imatinib is a small-molecule inhibitor that selectively blocks the activity of the PDGF-R, ABL and KIT receptor tyrosine kinases by competitive binding to the adenosine triphosphate binding site of their catalytic domains. We herein review the molecular pathological, preclinical and clinical data that identify imatinib as a valuable new agent in the treatment of GISTs.

Interventional therapy of vascular complications following renal transplantation

Abstract:  Renal transplantation is accepted as the preferred treatment for most cases of end‐stage renal disease. Postoperative vascular complications include stenosis or thrombosis of the transplant renal artery or arteriovenous fistulas after biopsy. Impaired arterial perfusion of the transplant may be the leading cause for graft dysfunction or refractory hypertension. Therefore, non‐invasive imaging modalities are required to detect and locate vascular complications with high accuracy. Doppler ultrasound is suited as a screening method for the detection of impaired graft perfusion. Magnetic resonance imaging (MRI) is used for an accurate diagnosis of vascular complications and to support decision for appropriate surgical or interventional treatment. Minimal invasive techniques like percutaneous transluminal angioplasty and stent placement have evolved as safe procedures with a high technical success rate reducing substantial morbidity. They can be considered as an alternative to surgical treatment of transplant renal artery stenosis (TRAS). Embolization of severe arteriovenous fistulas is the method of choice if the feeding artery can be occluded through a microcatheter. In selected cases, even catheter‐guided fibrinolytic treatment of arterial thrombosis might be considered, if instantaneous surgery is considered a high‐risk procedure. This article reviews the imaging features of common vascular complications after renal transplantation with focus on MRI. In addition, interventional radiological techniques are described for the treatment of TRAS, acute thrombotic occlusion, and arteriovenous fistulas.

Der Einsatz des Ultraschall- kontrastmittels Levovist® in der Nachsorge von Lebertransplantationen Verbesserung der Gefäßdarstellung in der Farbdopplersonographie

ZusammenfassungEinleitung: Klärung der Frage, ob mit Ultraschallkontrastmittel eine verbesserte Gefäßdarstellung bei Patienten nach orthotoper Lebertransplantation in der Farbdopplersonographie gelingt. Material und Methode: In der frühen postoperativen Phase nach Lebertransplantation wurden 31 Farbdopplersonographien bei 21 Patienten nativ und nach i.v. Gabe des Ultraschallkontrastmittels „Levovist®” (Schering AG, Berlin) durchgeführt. Bewertet wurden v.a. arterielle, aber auch portalvenöse und lebervenöse Flußsignale im Farb- und PW-Doppler nach einer 4-Punkte-Skala. Die Darstellung von arteriellen und portalvenösen Gefäßsignalen erfolgte zentral im Leberhilus sowie in beiden Leberlappen. Ergebnisse: Nach Kontrastmittelgabe gelang eine signifikante Verbesserung von arteriellen Signalen im Leberhilus bei 20 von 31 Sonographien, von peripheren Signalen bei 22 Untersuchungen im rechten und bei 26 im linken Leberlappen. Portalvenöse Signale wurden im rechten Leberlappen bei 17 von 31, im linken Leberlappen bei 16 Untersuchungen verbessert; im Leberhilus zeigte sich kaum eine Verbesserung. Keine Änderung ergab sich bei den Lebervenen. Durch die arterielle Signalverstärkung konnte bei wenigstens zwei Patienten auf eine weitere Diagnostik verzichtet werden. Schlußfolgerung: Frühe vaskuläre Probleme nach Lebertransplantation betreffen v.a. die Leberarterien. Mit kontrastmittelverstärkter Farbdopplersonographie gelingt eine Verbesserung von arteriellen und peripheren portalvenösen Signalen, die als Leitschienen zum Auffinden von kleinen Arterien dienen können.SummaryIntroduction: A study was carried out to determine whether an improvement in the detection of vascular signals in patients after orthotopic liver transplantation can be achieved by the use of ultrasound contrast medium in colour Doppler sonography. Material and methods: In the early postoperative follow-up of liver transplant recipients, 31 colour Doppler sonograms were obtained in 21 patients before and after intravenous injection of the ultrasound contrast agent Levovist® (Schering, Berlin). A grading score with four categories was used to evaluate the sonograms with special regard to the visibility of colour and flow signals in the hepatic artery and also in the portal vein and the hepatic veins. The arterial and portal venous signals were evaluated in the hepatic portal and in the left and right lobe. Results: With contrast enhancement significantly better arterial signals were seen in 20 of 31 sonograms for the hepatic portal, in 22 for the right lobe and in 26 for the left lobe. Better portal vein signals were obtained in 17 of 31 examinations for the right lobe and in 16 for the left lobe; only little improvement was obtained for the main stem of the portal vein. For the hepatic veins there was no significant improvement. Conclusion: Early vascular complications after liver transplantation usually occur in the hepatic arteries. With the use of contrast-enhanced colour Doppler sonography, better detection of arterial and peripheral portal signals can be achieved; peripheral portal vein branches can be helpful in find-ing small arteries.