Bispecific T-Cell Engager (BiTE) Antibody Construct Blinatumomab for the Treatment of Patients With Relapsed/Refractory Non-Hodgkin Lymphoma: Final Results From a Phase I Study

PURPOSE

Blinatumomab is a CD19/CD3 BiTE (bispecific T-cell engager) antibody construct for the treatment of Philadelphia chromosome-negative acute B-lymphoblastic leukemia. We evaluated blinatumomab in relapsed/refractory B-cell non-Hodgkin lymphoma (NHL).

PATIENTS AND METHODS

This 3 + 3 design, phase I dose-escalation study determined adverse events and the maximum tolerated dose (MTD) of continuous intravenous infusion blinatumomab in patients with relapsed/refractory NHL. Blinatumomab was administered over 4 or 8 weeks at seven different dose levels (0.5 to 90 μg/m(2)/day). End points were incidence of adverse events, pharmacokinetics, pharmacodynamics, and overall response rate.

RESULTS

Between 2004 and 2011, 76 heavily pretreated patients with relapsed/refractory NHL, who included 14 with diffuse large B-cell lymphoma, were enrolled; 42 received treatment in the formal dose-escalation phase. Neurologic events were dose limiting, and 60 μg/m(2)/day was established as the MTD. Thirty-four additional patients were recruited to evaluate antilymphoma activity and strategies for mitigating neurologic events at a prespecified MTD. Stepwise dosing (5 to 60 μg/m(2)/day) plus pentosan polysulfate SP54 (n = 3) resulted in no treatment discontinuations; single-step (n = 5) and double-step (n = 24) dosing entailed two and seven treatment discontinuations due to neurologic events, respectively. Grade 3 neurologic events occurred in 22% of patients (no grade 4/5). Among patients treated at 60 μg/m(2)/day (target dose; n = 35), the overall response rate was 69% across NHL subtypes and 55% for diffuse large B-cell lymphoma (n = 11); median response duration was 404 days (95% CI, 207 to 1,129 days).

CONCLUSION

In this phase I study of relapsed/refractory NHL, continuous infusion with CD19-targeted immunotherapy blinatumomab at various doses and schedules was feasible, with an MTD of 60 μg/m(2)/day. Single-agent blinatumomab showed antilymphoma activity.

[Experiences with power-injectable port systems: complications, patient satisfaction and clinical benefit]

PURPOSE

Evaluation of complications, patient satisfaction and clinical benefit of port systems with authorization for high pressure injection of contrast agent during CT/MR examinations.

MATERIALS AND METHODS

Ultrasound-guided insertions of central venous port catheters were performed through the lateral subclavian vein at a university teaching hospital. The radiological information system (HIS/RIS) was used to evaluate technical success and complication rates. Assessment of patient satisfaction and clinical benefit was carried out by a questionnaire during a telephone call 6 months after implantation of the port system.

RESULTS

A total of 195 port systems in 193 patients were implanted. The catheter remained in place for a mean duration of 169 days (overall 29,210 catheter days). The technical success rate was 99.5 % and the overall complication rate was 17.4 % (24/138; 0.82 per 1000 catheter days). Follow-up revealed 13 early port explantations (9 %). Most of the patients reported high satisfaction in general (satisfied/very satisfied: 94 %). 34/209 contrast-enhanced CT/MRT scans (16 %) were performed using the port for contrast media injection. There were no complications during or after administration of contrast agent via the port system.

CONCLUSION

The Powerport system is a safe alternative for peripheral i. v. contrast media injection during CT/MR scans, but has been infrequently used. Most patients reported high overall satisfaction with the port system.

Dynamic contrast-enhanced MRI for monitoring bisphosphonate therapy in Paget's disease of bone

PURPOSE

The purpose of this study was to evaluate changes in regional bone perfusion in Paget's disease (PD) following bisphosphonate therapy. We used dynamic contrast-enhanced MRI (DCE-MRI) for assessment of bone perfusion and compared MRI findings with alkaline phosphatase (AP) as a serum marker of bone turnover.

MATERIALS AND METHODS

We examined 20 patients (8 women, 12 men, 66 ± 11 years) with symptomatic PD of the axial skeleton. Patients were selected for infusion therapy with the bisphosphonate pamidronate. The most affected bone of lumbar spine or pelvis was examined by DCE-MRI prior to therapy and after a 6-month follow-up. The contrast uptake was evaluated using a two-compartment model with the parameters amplitude A and exchange rate constant K(ep). Color-coded parametric images were generated to visualize bone vascularization.

RESULTS

After a 6-month follow-up there was a significant decrease in alkaline phosphatase and in DCE-MRI parameters A and K(ep) (p < 0.0001). Patients without previous bisphosphonate treatment showed a significantly greater decrease in alkaline phosphatase and K(ep) (p < 0.001).

CONCLUSION

DCE-MRI shows a significant reduction in regional bone perfusion in PD following parenteral bisphosphonate treatment. Reduction in bone perfusion is greater in bisphosphonate-naïve patients than in those who had been previously treated.

Buttock Claudication After Interventional Occlusion of the Hypogastric Artery—A Mid-Term Follow-Up

Background. Interventional occlusion of the hypogastric artery (HA) can be used for endovascular aneurysm repair (EVAR) in the iliac arteries. Most frequent ischemic complication is buttock claudication (BC). Aim. To investigate the frequency and progression of BC after interventional occlusion of the HA prior to EVAR. Methods. A retrospective analysis was performed in patients with EVAR and occlusion of the HA between September 2004 and August 2010. Acute and persistent BC symptoms were assessed. Results. Fifty-four catheter occlusions of the HA were performed. In 10 cases, claudication could not be evaluated. During a mean follow-up of 17 months, 23 occlusions (52.3%) of the HA showed BC, in 52% symptoms were persistent. Of the 5 patients, 3 patients who underwent bilateral occlusion had BC and in 2 cases, persistent in the follow-up. Conclusion. Buttock claudication after occlusion of the HA prior to EVAR is a frequent complication, which often persists during follow-up. Alternatives that maintain pelvic perfusion should be considered.

Detection and size of pulmonary lesions: how accurate is MRI? A prospective comparison of CT and MRI

BACKGROUND

Although CT is the modality of choice for morphological lung imaging, an increasing proportion of chest imaging is performed by MRI due to the utilization of whole-body MRI. Therefore, the diagnostic performance of MRI in reliably detecting pulmonary lesions should be established.

PURPOSE

To investigate the detection rate of pulmonary lesions by MRI that can be expected in a clinical setting and to assess the accuracy of lesion measurement by MRI compared to CT.

MATERIAL AND METHODS

Twenty-eight patients (median age 66 years) with indication for CT imaging due to suspected thoracic malignancy were prospectively included. Chest MRI performed on the same day as CT, comprised unenhanced TrueFisp, ecg-gated T2-weighted HASTE, T1-weighted VIBE, and contrast-enhanced T1-weighted, fat-saturated VIBE sequences. MR sequences were evaluated for lesion detection by two readers independently and measurement of lesion size was performed. MR findings were correlated with CT.

RESULTS

One hundred and eight pulmonary lesions (20 thoracic malignancies, 88 lung nodules) were detected by CT in 26 patients. Lesions were ruled out in two patients. All thoracic malignancies were identified by MRI with strong correlation (r = 0.97-0.99; P < 0.01) in lesion size measurement compared to CT. Unenhanced, T1-weighted VIBE correctly classified 94% of thoracic malignancies into T-stages. Contrast-enhanced, T1-weighted VIBE performed best in identifying 36% of lung nodules, 40% were detected combining unenhanced and contrast-enhanced T1-weighted VIBE. Detection rate increased to 65% for the combined sequences regarding lesions ≥5 mm. Lesion size measurement by all MR sequences strongly correlated with CT (r = 0.96-0.97; P = 0.01).

CONCLUSION

MRI is as accurate as CT in detection and size measurement of primary thoracic malignancies >1 cm in diameter. If a lung lesion is detected by MRI, it is a reliable finding and its measurement is accurate. CT remains superior in detecting small lung nodules (<6 mm). Detection rate of MRI for small lesions is improved using a multi-sequence protocol including contrast administration.

Occlusion of the Internal Iliac Artery Prior EVAR

Purpose: We compared occlusion of the internal iliac artery (IIA) using coils or the Amplatzer vascular plug (AVP) II prior to endovascular aortic aneurysm repair. Materials and Methods: Occlusion of the IIA was performed in 32 patients (aged 74 ± 8 years) using coils (N = 17) or the AVP II (N = 15). We retrospectively compared procedural data, initial success, and clinical outcome in a 12-month follow-up. Results: Occlusion was successful in all patients without detection of an endoleak after 12 months. Procedure time and fluoroscopy time for coils versus plugs were 77 ± 35 versus 43 ± 13 minutes and 36 ± 19 versus 18 ± 8 minutes, respectively ( P < .003). Incidence of initial buttock claudication (BC) for coils versus plugs was 47% versus 27% and was significantly more severe after coil occlusion ( P = .03). After a 12-month follow-up, 2 patients of each group reported of mild BC. Conclusion: Occlusion of the IIA is safe and effective using coils or plugs. Initial BC is significantly more severe when coils are used, but after a 12-month follow-up, there is no significant difference. Using a plug is associated with a significant reduction of procedure time and radiation exposure.

Prediction of immediate and long-term benefit after kyphoplasty of painful osteoporotic vertebral fractures by preoperative MRI

BACKGROUND

It is unclear if an MR-detectable bone marrow edema is a prerequisite for pain reduction and morphological correction by kyphoplasty. This comparative trial evaluates clinical and radiomorphological outcomes after kyphoplasty of painful osteoporotic vertebral fractures with and without preoperative MR-detectable bone marrow edema for 1 year of follow-up.

METHODS

Preoperative MR-images of 45 patients who received kyphoplasty for treatment of painful osteoporotic vertebral fractures were evaluated with regard to presence (n = 27) or absence (n = 18) of vertebral bone marrow edema. Pain scores (VAS 0-100) and radiomorphological measures (midline vertebral height, kyphosis angle) were analysed at baseline, postoperatively and after 12 months.

RESULTS

In the "bone edema" group, pain scores improved from 72.7 to 46.8 (postoperative) and 48.0 (12 months, P < 0.001, both). In the group without preoperative bone edema, pain score improved from 70.7 to 60.3 (postoperative, P = 0.013) and to 50.1 (12 months, P = 0.001). Pain scores of both groups were significantly different directly postoperative (P = 0.026), but not after 12 months (P = 0.714). Vertebral height restoration was slightly greater in the "bone edema" group (10.2% vs. 7.8%, P = 0.289). Correction of the kyphosis angle was greater in the "bone edema" group (P = 0.014) compared to the "no bone edema" group (P = 0.838).

CONCLUSION

A preoperative MR-detectable vertebral bone marrow edema predicts a better short-term outcome after kyphoplasty, but is not a prerequisite for long-term pain reduction in patients with old, chronically painful osteoporotic vertebral fractures.

Occlusion of arteriovenous fistulas of in-situ saphenous vein bypass grafts using the amplatzer vascular plug 4: initial experience

We examined the safety and efficacy of vessel occlusion of the Amplatzer Vascular Plug 4 (AVP-4) in patients with arteriovenous fistulas after in-situ saphenous vein bypass grafts. We treated 18 fistulas of seven patients (four women, mean±standard deviation age 76±7 years, range 63-88 years). All fistulas were detected within 14 days after surgery. Initial diagnosis and follow-up was established by sonography. We measured the diameter of the feeding vessel and the time of vessel occlusion after plug deployment. Additionally, we recorded procedure time and the dose area product. Additional interventional procedures were necessary in three patients. We successfully used 19 AVP-4 for occlusion of all fistulas without thromboembolic complications. There was no need for recapturing the device, and we did not observe dislocation. Mean occlusion time was 9.6 min (range 5-22 min). Mean diameter of the feeding vessels was 3.5 mm (range 2.6-5.1 mm). Plug sizes ranged from 4-8 mm (mean 5.5 mm) resulting in an oversizing of 33-88%. Mean procedure time for patients with and without additional intervention was 91±38 min and 35±18 min, respectively. Mean dose area product was 11,790 cGy/cm2 (range 1,850-23,500 cGy/cm2). Permanent occlusion of the fistulas was confirmed by ultrasound after a mean follow-up of 4 months (1-6 months). Occlusion of arteriovenous fistulas with an AVP-4 seems to be effective and safe in patients with in-situ saphenous vein bypass grafts. The AVP-4 is well suited for this purpose because of the appropriate diameter of the feeding vessels.

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.

[Portal vein embolization using the amplatzer vascular plug II: preliminary results]

PURPOSE

In this study we examined the feasibility of portal vein embolization (PVE) by using the Amplatzer Vascular Plug (AVP-II). We measured the time of vessel occlusion after plug deployment and changes in plug length and diameter within 4 weeks of PVE.

MATERIALS AND METHODS

In 10 consecutive patients (4 women, age 64 +/- 10 yrs, 48 - 82 yrs) an ipsilateral PVE of the right portal vein was performed prior to intended hemihepatectomy. After embolization with microparticles, the right portal vein was occluded using an AVP-II. We measured the time of complete vessel occlusion by angiography. Follow-up with computed tomography (CT) was performed within 72 h and after 4 weeks.

RESULTS

PVE was performed in all 10 patients without acute complications. Complete vessel occlusion was achieved in 9.7 +/- 5.1 min (range 1 - 21 min). On follow-up CT we found enhanced arterial vascularization of the embolized liver segments in 5 / 5 patients within 72 hours and in 6 / 10 patients after 4 weeks. The plug showed a contraction of 20 +/- 9 % and a dilatation of 23 +/- 13 %. Thus, the AVP-II dilated to 94 +/- 8 % (78 - 100 %) of its nominal diameter. The plug diameter was significantly larger in men compared to women (17 +/- 1.7 mm vs. 14 +/- 1.4 mm, p < 0.02). We did not observe any recanalization or migration of the device. The volume of the left liver lobe increased significantly by 27 % (p < 0.001) after 4 weeks.

CONCLUSION

PVE with the AVP-II is a feasible and effective method. The AVP-II can dilate within 4 weeks up to its nominal diameter dependent on the grade of oversizing. Dilatation of the diameter is associated with a shortening in length.

[Arterial embolization of hepatic metastases from neuroendocrine tumors]

Neuroendocrine tumors are slowly growing neoplasms and 75% of patients already present with hepatic metastases at the time of diagnosis. Size and growth of liver metastases is of prognostic value. Due to arterial vascularization of metastases, transarterial embolization (TAE) is a suitable procedure, which can also be combined with chemotherapeutic agents. Indications for embolization or chemoembolization (TACE) are growth of liver metastases or inadequate symptom control. The majority of patients show clinical improvement and partial remission can be achieved in 50% of cases with 5-year survival rates of 50-60%. Response rates, survival or complications are not dependent on the embolization technique (TAE or TACE). Embolization is usually performed in several sessions depending on individual tumor stage and disease progression. Embolization is a cost-effective procedure and is included in the treatment algorithm of international guidelines. Therefore, evaluation of new embolization therapies must be evaluated in randomized controlled studies.

Late enhancement in cardiac amyloidosis: correlation of MRI enhancement pattern with histopathological findings

Late enhancement (LE) in cardiac magnetic resonance imaging (MRI) is a characteristic finding in patients with cardiac amyloidosis (CA) but the histomorphological explanation has not been clarified yet. Five patients with CA were evaluated by MRI prior to heart transplantation. This consisted of morphological, volumetric, and functional data, including LE analysis. For LE analysis, left ventricular (LV) short-axis sections from basal, midventricular, and apical positions were divided into 12 segments resulting in a 36-segment model. Each segment was differentiated by subendocardial, midmural, and subepicardial localization. Histological amyloid and collagenous fiber deposition was correlated with LE in corresponding MRI slides. LE was visualized in 103/180 (57.2%) predominantly subendocardial segments. Histological analysis of amyloid deposition was (peri-)vascular (n = 5), diffuse interstitial (n = 3) and/or nodular (n = 4). Extent of fibrosis was moderate to severe. Cytoplasmatic vacuolization and decline of myofibrils was seen in all patients. Fibrosis was significantly associated with LE in subendocardial and midmural localizations (p<0.05), whereas the extent of amyloid deposition was not associated with LE findings in any region. LE seems to be associated with fibrosis due to ischemia of cardiomyocytes by small vessel amyloid deposition rather than with amyloid deposition in CA, suggesting that amyloid deposition might be present prior to LE detection.

[MR imaging in cardiac amyloidosis--morphology, function and late enhancement]

PURPOSE

Since limited data is available using MR imaging in cardiac amyloidosis, the purpose of our study was to evaluate morphological and functional differences of the heart using cardiac MRI.

MATERIALS AND METHODS

19 consecutive patients (14 males, 5 females, mean age 59 +/- 6 years) with histologically proven cardiac amyloidosis were evaluated with MRI at 1.5 T. Results were compared with data of 10 healthy, age-matched control subjects (5 males, 5 females, mean age 60 +/- 6 years). Functional and morphological data including late enhancement (LE) was acquired.

RESULTS

Compared to the control group, patients with cardiac amyloidosis had thickened atrial walls and dilated atriums. Both ventricles and the interventricular septum were thickened. The LV hypertrophy was focal in 11 / 19 (58 %) and global in 4 / 19 (21 %) of patients. A myocardial edema occurred in 2 / 19 patients with cardiac amyloidosis (11 %). An edema of the myocardium was visible in 2 / 19 (11 %) of patients. The LV ejection fraction was statistically significantly decreased. The prevalence of LE was 74 % (14 / 19 of patients). LE was detected predominantly in the LV anterior wall and in the interventricular septum. Within the segments LE was located predominantly in a subendocardial location. Between patients with and without LE no statistically significant differences of functional and morphological results were able to be established.

CONCLUSION

There are three major outcomes of our assessment: 1. The LV hypertrophy is focal in the majority of patients with cardiac amyloidosis. 2. No statistically significant differences can be established in regard to the functional and morphological features between patients with and without LE. 3. Myocardial edema is a possible feature in cardiac amyloidosis.

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 >or=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.

Familial early onset sarcoidosis with bone cysts and erosions

Early onset sarcoidosis is a granulomatous disease which is characterized by synovitis, polyarthritis, skin and eye involvement. We report the skeletal features of one patient with a family history and clinical symptoms suggestive of early onset sarcoidosis (EOS) which was confirmed by skin biopsy. Radiographs reveal postarthritic deformities of the MCP joints, contractures, a coarsened trabecular pattern at the PIP joints and small bone cysts resembling osteitis cystoides multiplex. Similar lesions were described in radiographs of the older sister and an uncle of our patient. This is the first report demonstrating bone cysts and erosions which could be a diagnostic feature in this rare disease and may help to differentiate other rheumatoid disorders.

The intravertebral vacuum phenomen as specific sign of osteonecrosis in vertebral compression fractures: results from a radiological and histological study

This study investigated the prevalence of the intravertebral vacuum phenomenon (IVP) and osteonecroses in vertebral compression fractures (VCFs). We therefore performed an histological analysis of biopsies obtained from VCFs prior to balloon kyphoplasty. Computed tomography (CT) scans were reviewed regarding the presence of an IVP (i.e. cleft sign, Kümmell disease). We reviewed the data of 266 consecutive patients treated by balloon kyphoplasty in 501 procedures from 2002 to 2004. From 180 patients (68%) we obtained adequate bone tissue for histological evaluation. Biopsy specimens were analysed regarding the presence of osteoporosis, infection, malignancy and osteonecrosis. CT scans of all 180 patients were reviewed for presence of an IVP. Histological examination revealed 135 (75%) osteoporoses, 20 (11%) neoplasms, 12 (7%) trauma cases and 13 (7%) osteonecroses. An IVP was present in 12 (7%) patients. There was a significant association of osteonecrosis and IVP (P < 0.0001). Eleven of 12 patients with a vacuum phenomenon showed an osteonecrosis on histology, whereas 11 of 13 patients with osteonecrosis showed an IVP on CT. The IVP is a specific sign of osteonecrosis in vertebral compression fractures (sensitivity 85%, specificity 99%, positive predictive value 91%). Our findings strongly support the thesis that an IVP indicates local bone ischemia associated with a non-healing vertebral collapse and pseudarthrosis.

Wound complications following kidney and liver transplantation

Advances in surgical techniques and immunosuppression (IS) have led to an appreciable reduction in postoperative complications following transplantation. However, wound complications as probably the most common type of post-transplantation surgical complication can still limit these improved outcomes and result in prolonged hospitalization, hospital readmission, and reoperation, consequently increasing overall transplant cost. Our aim was to review the literature to delineate the evidence-based risk factors for wound complications following kidney and liver transplantation (KTx, LTx), and to present the preventive and therapeutic modalities for this bothersome morbidity. Generally, wound complications are categorized as superficial and deep wound dehiscences, perigraft fluid collections and seroma, superficial and deep wound infections, cellulitis, lymphocele and wound drainage. The results of several studies showed that the most important risk factors for wound complications are IS and obesity. Additionally, there are surgical and/or technical factors, including type of incision, reoperation, and surgeon's expertise, as well as comorbidities such as advanced age, diabetes mellitus, malnutrition, and uremia. Preventive management of wound complications necessitates defining their etiological factors so that their detrimental effects on healing processes can be addressed and reduced. IS modalities and agents, especially sirolimus (SRL), and steroids (ST) should be adjusted according to the patient's co-existing risk factors. SRL should be administered three months after transplantation and ST should be tapered as soon as possible. A body mass index (BMI) lower than 30 kg/m2 is advisable for inclusion in a transplantation program, but higher BMIs do not exclude recipients. Surgical risk factors can be prevented by applying precise surgical techniques. Therapeutic modalities must focus on the most efficient and cost-effective medications and/or interventions to facilitate and improve wound healing.

[Balloon kyphoplasty in the therapy of vertebral fractures]

Approximately 500,000 vertebral fractures occur as a result of osteoporosis every year in Europe. One third of the patients thus affected complain of severe back pain and seek treatment. In the past, the treatment of such fractures was limited to conservative methods, such as the use of braces and analgesics and long-term immobilisation followed by physiotherapy. Since 1998 balloon kyphoplasty, a minimally invasive procedure, has also been available for their treatment. During balloon kyphoplasty a balloon system is introduced into a fractured vertebral body to achieve bitranspedicular augmentation, after which low-viscosity bone cement is injected into the vertebral body, where it sets very quickly. In general the patient can be fully mobilized 24-48 h after the procedure and in most cases the symptoms are then considerably attenuated; many patients are actually free of pain. Published studies and our own experience indicate that balloon kyphoplasty is a safe method of treating painful vertebral compression fractures sustained in various ways and that complications are rare with this procedure.

[Balloon kyphoplasty in the treatment of vertebral fractures]

Approximately 500,000 vertebral fractures occur as a result of osteoporosis every year in Europe. One third of the patients thus affected complain of severe back pain and seek treatment. In the past, the treatment of such fractures was limited to conservative methods, such as the use of braces and analgesics and long-term immobilisation followed by physiotherapy. Since 1998 balloon kyphoplasty, a minimally invasive procedure, has also been available for their treatment. During balloon kyphoplasty a balloon system is introduced into the fractured vertebral body to achieve bitranspedicular augmentation, after which low-viscosity bone cement is injected into the vertebral body, where it sets very quickly. In general the patient can be fully mobilized 24-48 h after the procedure and in most cases the symptoms are then considerably attenuated; many patients are actually free of pain. Published studies and our own experience indicate that balloon kyphoplasty is a safe method of treating painful vertebral compression fractures sustained in various ways and that complications are rare with this procedure.

Interventional therapy of vascular complications following renal transplantation

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.

[Balloon kyphoplasty in the treatment of back pain]

BACKGROUND

Experience of just under 5 years has shown that balloon kyphoplasty can be just as successfully employed as the longer-stablished vertebroplasty for the treatment of back pain due to recent or prior osteoporotic fractures as well as new traumatic fractures.

MATERIAL AND METHOD

Among 345 patients with a total of 690 treated vertebral bodies, the change in pain symptomatology was analyzed for a follow-up period of 12 months in 40 study patients who underwent kyphoplasty and a control group of 20 patients. In addition, the pain experienced by a further 29 patients with new traumatic vertebral body fractures was monitored over a 12-month period. These fractures were partly managed by fixateur interne alone and by a combination of fixateur interne and kyphoplasty.

RESULTS

The 40 patients treated by kyphoplasty had a baseline VAS score of 26.2+/-2.00, which increased to 44.4+/-3.11 after 12 months, while the respective scores for the control group were 33.6+/-4.21 and 34.3+/-4.35. In the 29 patients with new traumatic vertebral body fractures, the initial VAS score was 62 and after 12 months a distinct reduction of pain was noted with a score of 20 (100 = maximum pain, 0 = no pain). The number of times that the 40 patients managed by kyphoplasty had to consult their general practitioner was significantly reduced by the pain therapy.

CONCLUSION

Balloon kyphoplasty verifiably improved the pain symptomatology after vertebral fracture over a period of 12 months. Comparison with the control group, which received the same osteoporosis drug therapy, confirmed the effect of this minimally invasive treatment form.

Transarterial embolization of primary and secondary tumors of the skeletal system

Percutaneous transcatheteral embolizations of primary and secondary bone tumors are important minimal invasive angiographic interventions of the skeletal system. In most of the cases embolization is performed for preoperative devascularization or as a palliative measure to treat tumor-associated pain or other tumor bulk symptoms. The transarterial embolization of primary and secondary tumors of the skeletal system has been developed to a safe and very effective method. Indications, techniques, results and complications of this minimal invasive interventional therapy for treatment of primary and secondary bone tumors are described and discussed and compared with the newer literature and our own results.