Monday, December 16, 2019

Safety and Efficacy of Sacroplasty for Sacral Fractures: A Systematic Review and Meta-Analysis


Clinical Question
What is the safety and efficacy of sacroplasty for the treatment of osteoporotic and malignant sacral fractures?

Take-Away Point
Sarcoplasty is a safe procedure for treating painful sacral insufficiency fractures resulting from osteoporosis or metastasis and reduces patient pain scores up to a year post-procedure.

Reference
Chandra, Vishnu et al. Safety and Efficacy of Sacroplasty for Sacral Fractures: A Systematic Review and Meta-Analysis. Journal of Vascular and Interventional Radiology, Volume 30, Issue 11, 1845 - 1854.

Click here for abstract

Study Design
Systematic review and meta-analysis

Funding Source
Self-funded or unfunded

Setting
Multi-center







Summary

Sacral insufficiency fractures (SIFs) are a common and growing cause of lower back pain in the elderly population and are often a result of osteoporosis or metastatic spread to the sacrum. Standard therapies consist of conservative management with rest, analgesia, and physical therapy. They are associated with deconditioning, deep venous thrombosis/pulmonary embolism, and psychiatric disease. Sarcoplasty is an evolving minimally-invasive therapy aimed at reducing patient pain due to SIF and allowing improved quality of life and function.

In this meta-analysis and systematic review, 19 retrospective and prospective case series were analyzed for a pooled cohort of 861 patients undergoing 867 procedures. Patients all had sacral insufficiency fractures, with 664 secondary to osteoporosis, 67 to malignancy, and 30 non-specified. Included studies measured pre- and post-procedural pain via the visual analog scale (VAS) as reported by the patient prior to and up to 18 months after sarcoplasty. Complications of the procedure and follow-up treatment were also measured.

VAS scores at pre-procedure, 24–48 hours, 6 months, and 12 months yielded cumulative pain scores of 8.35 ± 0.14 (n=861), 2.70 ± 0.26 (n=749), 2.26 ± 0.24 (n=352), and 2.01 ± 0.34 (n=357), respectively. There was no significant difference in mean pain scores between patients with osteoporotic SIFs and patients with SIF secondary to metastatic disease at any time point. Clinical success (defined as patient-reported pain relief) occurred in 623 of 651 (95.7%) of cases where post-procedural clinical status was evaluated.

Cement leakage was reported in 19 of 867 cases (2.2%), which resulted in clinical symptoms in 5 patients. 3 of these required surgical decompression while 2 were treated successfully with conservative management. No other complications, including infection, bleeding, or pulmonary embolism were reported.

Commentary

In this meta-analysis and systematic review, sarcoplasty was shown to be safe and effective at relieving patient pain up to a year from the procedure. Other outcomes, such as patient functional status, mobility, satisfaction, or use of pain medications (such as opioids) were not measured. Future investigations should compare sarcoplasty versus sham and conservative therapies in the form of randomized controlled trials, while future retrospective studies should measure the long-term efficacy and safety of sarcoplasty as well as the use of opioids and patient functional status.
 
Post Author

Jared Edwards
4th Year Medical Student
Oregon Health & Science University School of Medicine, Portland, OR

Friday, December 13, 2019

Percutaneous Costoclavicular Bypass for Thoracic Outlet Syndrome and Cephalic Arch Occlusion in Hemodialysis Patients

 
Clinical Question
Report results of percutaneous costoclavicular bypass for symptomatic thoracic outlet or cephalic arch occlusion in patients with arteriovenous fistula.

Take-Away Point
Percutaneous costoclavicular bypass is a feasible option for thoracic outlet and cephalic arch occlusion in symptomatic dialysis patients.

Reference

Hull, J. and J. Snyder (2019). "Percutaneous Costoclavicular Bypass for Thoracic Outlet Syndrome and Cephalic Arch Occlusion in Hemodialysis Patients." J Vasc Interv Radiol 30(11): 1779-1784.

Click here for abstract

Study Design
Retrospective chart review of patients undergoing percutaneous costoclavicular bypass.

Funding Source

No reported funding

Setting
Richmond Vascular Center, North Chesterfield, VA






Figure 1. Key steps of costoclavicular bypass.

Summary


Intravascular treatment of venous outflow stenosis in patients with thoracic outlet syndrome and cephalic arch pathology has been limited by external compression at the costoclavicular junction. Subcutaneous costoclavicular bypass is a minimally invasive alternative to surgical decompressive options such as first rib resection and claviculectomy.

A retrospective chart review of 9 patients undergoing percutaneous costoclavicular bypass was performed. Inclusion criteria comprised patients with ESRD, AV fistula, and symptomatic occlusion of the cephalic arch or subclavian vein with previous failure of standard therapies. One patient received a Gore Hybrid vascular graft, all other cases were performed using Viabahn stent grafts.

The percutaneous costoclavicular bypass was technically successful in 100% of cases. All patients had symptomatic improvement at 1 week. There were no immediate complications. At 12 months and 24 months, primary patency was 67% and 67%. Secondary patency was 89% and 78%. The Viabahn stent graft achieved a hemostatic seal in all cases and the stent grafts remained intact at follow up.

One patient demonstrated stent migration at the fistula outflow, which was treated with overlapping stent graft extension. Loss of costoclavicular bypass occurred in 3 patients. One stent graft was secondarily infected 5 months after placement and was subsequently excised. The Gore hybrid graft kinked and required over-stenting with bare metal and covered stents, leading to graft thrombosis and edge stenosis, and was abandoned after 3 years.

 

Commentary


Percutaneous costoclavicular bypass demonstrates early clinical success in this retrospective study. While this study is limited by the inclusion criteria and small patient population, the patency rates, high technical success rates, and high clinical success rates are promising. Notably, the authors did not report any stent compression, buckling, or deformity. The durability of the Viabahn stent graft opens the door for other potential percutaneous, subcutaneous bypass procedures. While percutaneous costoclavicular bypass shows early clinical success, further research is required to determine success in larger patient populations.

Post Author

Maxwell R. Cretcher, DO
Resident Physician, Integrated Interventional Radiology
Dotter Department of Interventional Radiology
Oregon Health & Science University

Monday, December 9, 2019

Correlation of CT Angiography and 99mTechnetium-Labeled Red Blood Cell Scintigraphy to Catheter Angiography for Lower Gastrointestinal Bleeding: A Single-Institution Experience


Clinical Question
Can greater adoption of CT angiography or 99mTechnetium-labeled red blood cell (RBC) scintigraphy reduce the number of nontherapeutic catheter angiography (CA) in the management of lower gastrointestinal bleeding (LGIB)?

Take-away Point
Greater adoption of CT angiography rather than RBC scintigraphy may reduce the number of nontherapeutic CAs given CT’s greater positive correlation to CA and non-increased nephrotoxicity.

Reference
Correlation of CT Angiography and 99mTechnetium-Labeled Red Blood Cell Scintigraphy to Catheter Angiography for Lower Gastrointestinal Bleeding: A Single-Institution Experience. Speir, E. J. et al. Journal of Vascular and Interventional Radiology (JVIR), Volume 30, Issue 11, 1725-1732.

Study design
Single-institution, retrospective study of 223 CAs with either pre-procedural CT angiography, RBC scintigraphy, or both for LGIB with laboratory creatinine review 48-72 hours after CA.

Funding Source

No reported funding

Setting

Academic hospital, Emory University Hospital, United States of America.







Figure 2.  Positive predictive values of CT angiography (CTA) compared to RBC scintigraphy (NM for nuclear medicine) overall, across clinical variants of LGIB, overall excluding Variant 4 LGIB, and studies completed within 4 hours of CA.

Summary


99mTechnetium-labeled red blood cell (RBC) scintigraphy has traditionally served as the initial diagnostic study for imaging evaluation of lower gastrointestinal bleeding (LGIB) given its superior sensitivity. However, frequent subsequent non-therapeutic catheter-based intervention following positive RBC scintigraphy and the advances of CT angiography with superior localization capability have led to the proposal of incorporating CT angiography into the standard management of LGIB. Nonetheless, there was a paucity of literature on the comparative correlations between the two modalities to subsequent catheter angiography. Effects of additional contrast dose on renal function with CT angiography prior to catheter angiography also remained unclear.

The authors performed a retrospective, single institution (3 practicing hospitals) of 223 cases (unique patient count of 207) of catheter angiography for evaluation of LGIB with pre-procedural CT angiography, RBC scintigraphy, or both. Catheter angiography was used as the reference standard. All 4 variants of LGIB were included and were used for sub-analysis. Exclusion criteria included no CT angiography or RBC scintigraphy within 30 hours of catheter angiography, prophylactic embolization, provocative catheter angiography, and inadequate pre-procedural imaging or procedural evaluation.

Out of the 223 cases of catheter angiography, 38 had CT angiography, 173 had RBC scintigraphy, and 12 had both types of pre-procedural imaging. The authors found CT angiography had a higher positive correlation of 67.7% with catheter angiography, compared to 29.3% of RBC scintigraphy. This difference was more dramatic if the pre-procedural imaging were completed within 4 hours preceding catheter angiography. Interestingly, positive correlation of RBC scintigraphy with catheter angiography was reported to be 75.0% when performed within 1 hour of catheter angiography. No significant dose-toxicity relationship between contrast and renal function was found. No significant differences of CIN incidence was found between the two arms.

Commentary


The authors in this study have demonstrated greater positive correlation of CT angiography with catheter angiography compared to RBC scintigraphy for assessing LGIB. Furthermore, they have showed non-increased nephrotoxicity associated with the additional contrast dose when CT angiography was utilized prior to catheter angiography. This study, with its retrospective nature and unequal CT angiography versus RBC scintigraphy case proportions, had its inherent limitations. Clinicians and proceduralists would have skewed towards proceeding with catheter angiography or not given the known high negative predictive value of CT angiography and high sensitivity of RBC scintigraphy. Therefore, future prospective randomized clinical trials may be necessary to definitely answer the question. The timing aspect, however, should not be understated. Dramatically increased positive correlations to catheter angiography were observed with shorter positive pre-procedural imaging to catheter angiography time regardless of the imaging choice. This highlighted the importance of prompt transitioning from pre-procedural imaging to catheter-based intervention which should be an important focus of a standardized LGIB management protocol.

Post Author
Ningcheng (Peter) Li, MD, MS
Integrated Interventional Radiology Resident, PGY-3
Department of Interventional Radiology
Oregon Health and Science University, Dotter Interventional Institute

@NingchengLi