Evaluation of degenerative disease of the lumbar spine: MR/MR myelography versus conventional myelography/post-myelography CT

BACKGROUND

To compare the use of magnetic resonance (MR)/MR myelography (MRM) with conventional myelography/post-myelography CT (convM) for detailed surgery planning in degenerative lumbar disease.

METHODS

Twenty-six patients with suspected complex lumbar degenerative disease underwent MRM in addition to convM as preoperative workup. Surgery was planned based on convM-as usual at our department. Post hoc, surgical planning was repeated planned again-now based on MRM. Furthermore, the MRM-based planning was performed by six independent neurosurgeons (three groups) of different degrees of specialisation.

RESULTS

In only 31 % of the patients, post hoc MRM-based planning resulted in the same surgical decision as originally performed, whereas in 69 % (n = 18) a different procedure was indicated. In patients with non-concurring convM- and MRM-based surgical plans, a less extended procedure was the result of MRM in six patients (23 %), a more extended one in five (19 %), and a related to side/level of decompression or nucleotomy different plan in six patients (23 %). In one patient (4 %), the MRM-based planning would have led to a completely different surgery compared to convM. Overall interobserver agreement on the MRM-based planning was substantial.

CONCLUSIONS

Detailed planning of operative procedures for complex lumbar degenerative disease is highly dependent on the image modality used.

The significance of bremsstrahlung SPECT/CT after yttrium-90 radioembolization treatment in the prediction of extrahepatic side effects

Purpose Unwanted deposition of 90Y microspheres in organs other than the liver during radioembolization of liver tumours may cause severe side effects such as duodenal ulcer. The aim of this study was to evaluate the significance of posttherapy bremsstrahlung (BS) SPECT/CT images of the liver in comparison to planar and SPECT images in the prediction of radioembolization-induced extrahepatic side effects.Methods A total of 188 radioembolization procedures were performed in 123 patients (50 women, 73 men) over a 2-year period. Planar, whole-body and BS SPECT/CT imaging were performed 24 h after treatment as a part of therapy work-up.Any focally increased extrahepatic accumulation was evaluated as suspicious. Clinical follow-up and gastroduodenoscopy served as reference standards. The studies were reviewed to evaluate whether BS SPECT/CT imaging was of benefit.Results In the light of anatomic data obtained from SPECT/CT, apparent extrahepatic BS in 43% of planar and in 52% of SPECT images proved to be in the liver and hence false positive.The results of planar scintigraphy could not be analysed further since 12 images were not assessable due to high scatter artefacts. On the basis of the gastrointestinal (GI)complications and the results of gastroduodenoscopy, true positive,true-negative, false-positive and false-negative results of BS SPECT and SPECT/CT imaging in the prediction of GI ulcers were determined. The sensitivity, specificity, positive and negative predictive values and the accuracy of SPECT and SPECT/CT in the prediction of GI ulcers were 13%, 88%, 8%,92% and 82%, and 87%, 100%, 100%, 99% and 99%,respectively.Conclusion Despite the low quality of BS images, BSSPECT/CT can be used as a reliable method to confirm the safe distribution of 90Y microspheres and in the prediction of GI side effects.

[Percutaneous Stone Treatment Today: Standard-, Mini-, Micro-, Ultramini-PCNL]

BACKGROUND

Percutaneous nephrolithotripsy (PCNL) is one of the main interventional treatment modalities for large kidney stones (> 2 cm diameter). With the implementation of miniaturised techniques the indications for PCNL have been broadened to smaller stones. Especially for urologists without emphasis on endourology it is difficult to have an overview of the growing multitude of available systems and techniques. This article describes the currently available systems for percutaneous stone treatment with their peculiarities and indications.

MATERIALS AND METHODS

A PubMed-based literature search has been conducted. Relevant articles and additional manufacturers' literature have been compiled to create a summary of the different available PCNL systems. Furthermore, a brief literature review is given regarding indications, stone-free rates and complication rates of each system category.

RESULTS

Several manufacturers have developed different PCNL systems with varying diameters and special features. The indications for the different systems are overlapping. Retrospective studies showed reduced complication rates (especially less bleeding and need for transfusions) but prospective randomised controlled trials on this topic are still lacking. Assessed with the criteria of evidence-based medicine, the currently available evidence does not clearly answer the question whether a miniaturisation of PCNL systems is advantageous for the patient.

CONCLUSION

Invasiveness of PCNL can be reduced with the nowadays available miniaturised systems. The indication for PCNL has been broadened to small kidney stones > 1 cm diameter.

Renal denervation: results of a single-center cohort study

PURPOSE

To investigate the effect of renal denervation on office-based and 24-h ambulatory blood pressure measurements (ABPM) in a highly selective patient population with drug-resistant hypertension.

MATERIALS AND METHODS

Patients with drug resistant hypertension eligible for renal denervation were included in the study population. Office blood pressure and ABPM were assessed prior to and after renal denervation. To detect procedure related renal or renal artery damage, magnetic resonance imaging (MRI) and angiography (MRA) were performed pre-interventional, one day post-interventional, and one month after renal denervation.

RESULTS

Mean follow-up time between renal denervation and blood pressure re-assessment was 9.5 ± 3.9 months. Between August 2011 and March 2013, 17 patients prospectively underwent renal denervation. Pre-interventional mean office blood pressure and ABPM were 177.3 ± 20.3/103.8 ± 20.4 mmHg and 155.2 ± 20.5/93.7 ± 14.5 mmHg, respectively. Post-interventional, office blood pressure was significantly reduced to 144.7 ± 14.9/89.5 ± 12.1 (p < 0.05). ABPM values remained unchanged (147.9 ± 20.3/90.3 ± 15.6, p > 0.05). The number of prescribed antihypertensive drugs was unchanged after renal denervation (4.7 ± 2.0 vs. 4.2 ± 1.2, p = 0.18). No renovascular complications were detected in follow-up MRI.

CONCLUSION

After renal denervation, no significant decrease in ABPM was observed. These results may indicate a limited impact of renal denervation for drug resistant hypertension.

KEY POINTS

• Renal denervation showed no significant effects on 24-h ambulatory blood pressure measurements. • A significant decrease in office blood pressure measurements may be explained by a potential detection bias. • Renal artery alterations were not observed on follow-up MRI scans.

0.125 mm(3) spatial resolution steady-state MR angiography of the thighs with a blood pool contrast agent using the quadrature body coil only at 1.5 Tesla

PURPOSE

To implement and evaluate high spatial resolution three-dimensional MR contrast-enhanced angiography (3D-CEMRA) of the thighs using a blood pool contrast agent (BPCA) using the quadrature body coil only in patients with peripheral arterial occlusive disease (PAOD) in cases receiver coils cannot be used at 1.5 Tesla (T).

MATERIALS AND METHODS

Nineteen patients (mean age: 68.7 ± 11.2 years; range, 38-83 years) with known PAOD (Fontaine stages; III: 16, IV: 3) prospectively underwent 3D-CEMRA at 1.5T with a noninterpolated voxel size of 0.49 × 0.49 × 0.48 mm(3) . Digital subtraction angiography (DSA) was available for comparison in all patients. Two readers independently evaluated movement artifacts, overall image quality of 3D-CEMRA, and grade of stenosis as compared to DSA. SNR and CNR levels were quantified.

RESULTS

The 3D-CEMRA was successfully completed in all patients. Patient movement artifacts that affected stenosis grading occurred in 3/38 thighs. Overall image quality was rated excellent in 15/38, good in 12/38, and diagnostic in 8/38 thighs. Stenosis grading matched with that in DSA in 35/38 thighs. High SNR and CNR were measured in all vessels.

CONCLUSION

The 0.125 mm(3) spatial resolution 3D-CEMRA of the thighs with a BPCA is feasible using a quadrature body coil exclusively with excellent image quality despite long acquisition times. J. Magn. Reson. Imaging 2014;40:996-1001. © 2014 Wiley Periodicals, Inc.

Survival after 131I-labeled lipiodol therapy for hepatocellular carcinoma

This study investigated the efficacy of 131iod- ine-labeled lipiodol (1311-lipiodol) as a palliative therapy, evaluated overall survival (OS) across Barcelona Clinic Liver Cancer (BCLC) stages, and determined the main prognostic factors influencing OS in patients with hepatocellular carcinoma (HCC). Patients, methods: We retrospectively analyzed 57 (44 men; mean age, 65.7 years; mean activity per session, 1.6 GBq; mean cumulative activity in patients with >1 sessions, 3.9 GBq) HCC patients who underwent 1311-lipiodol therapy. A majority of patients exhibited Child-Pugh class B (53.6%) disease and a good Eastern Cooperative Oncology Group performance status (0-1; 72%). Multinodular disease was observed in 87.7% patients, bilobar disease in 73%, and portal vein occlusion (PVO) in 54%. Furthermore, 21.1% patients were staged as BCLC B and 59.6 % as BCLC C. All patients were followed until death. Results: The median OS was 6.4 months, which varied significantly with disease stage (median OS for BCLC A, B, C, and D was 29.4, 12.0, 4.6, and 2.7 months, respectively; p = 0.009); Child-Pugh score and class; presence of ascites, PVO, or extrahepatic disease; largest lesion size; favourable treatment response; international normalized ratio, baseline albumin and alpha-fetopro- tein levels. Patients with a Child-Pugh A liver disease had a longer OS. Conclusion: Currently, different treatment modalities for HCC include radioembolization, transarterial chemoemboliz- ation, and systemic therapy with sorafenib; however, 1311-lipiodol therapy remains a feasible alternative for patients without a favourable response to other therapies, particularly for patients with Child-Pugh A liver cirrhosis.

Retrospective evaluation of safety and effectiveness of the EXOSEAL vascular closure device for single vascular closure and closure after repeat puncture in diagnostic and interventional radiology: single-center experience

PURPOSE

To retrospectively evaluate the safety and effectiveness of the EXOSEAL vascular closure device (VCD) for first or repeated closure after retrograde percutaneous femoral arterial access.

MATERIALS AND METHODS

A retrospective analysis of 417 patients (271 men; mean age, 64.1 y±12.8; age range, 22-94 y) who had undergone arterial closure with the EXOSEAL VCD was performed. Procedures with retrograde femoral access and closure with the 5-F, 6-F, or 7-F EXOSEAL VCD according to the manufacturer's instructions were included. The clinical indications included the full procedural portfolio of a radiologic department with a focus on transarterial hepatic procedures. After EXOSEAL VCD closure, patients were restricted to bed rest for 4 hours.

RESULTS

From August 2010 to March 2012, a total of 682 EXOSEAL VCDs (5-F, n = 276; 6-F, n = 394; 7-F, n = 12) were used in 659 procedures with a total of 404 repeated closures. The EXOSEAL VCD was used successfully in 676 of 682 procedures (99.1%). Hemostasis was achieved in 651 of 682 procedures (95.5%). No major complications were encountered. There were eight cases (1.17%) of minor complications despite a successful vascular closure procedure, none requiring further therapy. There were no complications in any of the 404 cases of repeated vascular closure.

CONCLUSIONS

The results of this study suggest that the EXOSEAL VCD is safe and effective in single and repeated closure of retrograde percutaneous femoral arterial access in interventional radiology cases.

Establishment and characterization of the Masquelet induced membrane technique in a rat femur critical-sized defect model

The Masquelet induced membrane technique for reconstructing large diaphyseal defects has been shown to be a promising clinical treatment, yet relatively little is known about the cellular, histological and biochemical make-up of these membranes and how they produce this positive clinical outcome. We compared cellular make-up, histological changes and growth factor expression in membranes induced around femur bone defects and in subcutaneous pockets at 2, 4 and 6 weeks after induction, and to the periosteum. We found that membranes formed around bone defects were similar to those formed in subcutaneous pockets; however, both were significantly different from periosteum with regard to structural characteristics, location of blood vessels and overall thickness. Membranes induced at the femur defect (at 2 weeks) and in periosteum contain mesenchymal stem cells (MSCs; STRO-1⁺ ) which were not found in membranes induced subcutaneously. BMP-2, TGFβ and VEGF were significantly elevated in membranes induced around femur defects in comparison to subcutaneously induced membranes, whereas SDF-1 was not detectable in membranes induced at either site. We found that osteogenic and neovascular activity had mostly subsided by 6 weeks in membranes formed at both sites. It was conclude that cellular composition and growth factor content in induced membranes depends on the location where the membrane is induced and differs from periosteum. Osteogenic and neovascular activity in the membranes is maximal between 2 and 4 weeks and subsides after 6. Based on this, better and quicker bone healing might be achieved if the PMMA cement were replaced with a bone graft earlier in the Masquelet technique. Copyright © 2013 John Wiley & Sons, Ltd.

Comparison of the survival and tolerability of radioembolization in elderly vs. younger patients with unresectable hepatocellular carcinoma

BACKGROUND & AIMS

The European Network on Radioembolization with Yttrium-90 resin microspheres study group (ENRY) conducted a retrospective study to evaluate the outcomes among elderly (≥ 70 years) and younger patients (<70 years) with unresectable hepatocellular carcinoma (HCC) who received radioembolization at 8 European centers.

METHODS

Patients with confirmed diagnosis of unresectable HCC who either progressed following resection or locoregional treatment and/or who were considered poor candidates for chemoembolization were evaluated by a multidisciplinary team for radioembolization with (90)Y-resin microspheres (SIR-Spheres; Sirtex Medical). The survival outcome and all adverse events were compared between the two age groups.

RESULTS

Between 2003 and 2009, 128 elderly and 197 younger patients received radioembolization. Patients in both groups had similar demographic characteristics. Many elderly and younger patients alike had multinodular, BCLC stage C disease, invading both lobes (p = 0.648). Elderly patients had a lower tumor burden, a smaller median target liver volume (p = 0.016) and appeared more likely to receive segmental treatment (p = 0.054). Radioembolization was equally well tolerated in both cohorts and common procedure-related adverse events were predominantly grade 1-2 and of short duration. No significant differences in survival between the groups were found (p = 0.942) with similar median survival in patients with early, intermediate or advanced BCLC stage disease.

CONCLUSIONS

Radioembolization appears to be as well-tolerated and effective for the elderly as it is for younger patients with unresectable HCC. Age alone should not be a discriminating factor for the management of HCC patients.