Image-guided cryoablation for the treatment of painful musculoskeletal metastatic disease: a single-center experience.

PURPOSE: The role of image-guided thermal ablation techniques for the nonoperative local management of painful osseous metastatic disease has expanded during recent years, and several advantages of cryoablation in this setting have emerged. The purpose of this study is to retrospectively evaluate and report a single-center experience of CT-guided percutaneous cryoablation in the setting of painful musculoskeletal metastatic disease. METHODS: This study was approved by the institutional review board and is compliant with the Health Insurance Portability and Accountability Act. Electronic medical records of all patients who underwent percutaneous image-guided palliative cryoablation at our institution were reviewed (n = 61). An intent-to-treat analysis was performed. Records were reviewed for demographic data and anatomical data, primary tumor type, procedure details, and outcome-including change in analgesic requirements (expressed as morphine equivalent dosages), pain scores (utilizing the clinically implemented visual analog scale), subsequent therapies (including radiation and/or surgery), and complications during the 24 h following the procedure and at 3 months. Patients were excluded (n = 7) if data were not retrospectively identifiable at the defined time points. RESULTS: Fifty-four tumors were ablated in 50 patients. There were statistically significant decreases in the median VAS score and narcotic usage at both 24 h and 3 months (p < 0.000). Six patients (11%) incurred complications related to their therapy. Two patients had no relief at 24 h, of which both reported worsened pain at 3 months. One patient had initial relief but symptom recurrence at 3 months. Four patients went on to have radiation therapy of the ablation site at some point following the procedure. CONCLUSIONS: CT-guided cryoablation is a safe, effective, reproducible procedural option for the nonoperative local treatment of painful musculoskeletal metastatic disease.

Palliative procedures for the interventional oncologist.

OBJECTIVE: The purpose of this article is to present our experience using multimodality interventional radiologic techniques for the treatment of cancer-related pain across a spectrum of abnormalities. CONCLUSION: Percutaneous imaging-guided thermal ablation has emerged as a safe and efficacious treatment for painful osseous metastases. The implementation of interventional thermal ablative techniques for the treatment of intractable pain secondary to malignancy can be further expanded to include transcatheter and combination procedures.

Percutaneous CT-guided cryoablation of the dorsal penile nerve for treatment of symptomatic premature ejaculation.

PURPOSE: To evaluate expansion of image-guided interventional cryoablation techniques usually employed for pain management to address the feasibility, safety, and efficacy of treatment for a urologic condition with otherwise limited treatment options, premature ejaculation (PE). MATERIALS AND METHODS: Prospective institutional review board approval was obtained, and 24 subjects with PE were enrolled. All patients underwent unilateral percutaneous computed tomography-guided cryoablation of the dorsal penile nerve (DPN). Postprocedural intravaginal ejaculatory latency times (IELTs) and PE Profile (PEP) results served as outcome variables. In addition, subjects were asked whether they would have the procedure done again based on their experience at the 180- and 360-day marks. RESULTS: The technical success rate was 100%. Baseline average IELT was 54.7 seconds ± 7.8 (n = 24), which increased to a maximum of 256 seconds ± 104 (n = 11; P = .241) by day 7 and decreased to 182.5 seconds ± 87.8 (n = 6; P = .0342) by day 90. The mean IELT remained at 182.5 seconds ± 27.6 at day 180 (n = 23; P<.0001) and decreased to 140.9 seconds ± 83.6 by 1 year (n = 22; P<.001). PEP scores improved overall, IELTs significantly improved at 180 and 360 days, and 83% of subjects reported that they would undergo the procedure again if given the same opportunity. There were no procedure-related complications. CONCLUSIONS: CT-guided percutaneous unilateral cryoablation of the DPN is a feasible, safe, single-day outpatient procedure for the treatment of symptomatic PE.

Contrast-induced nephropathy and nephrogenic systemic fibrosis: minimizing the risk.

INTRODUCTION: Contrast-enhanced cross-sectional imaging is essential to the urologist's practice. Traditionally, patients with impaired renal function could not be imaged with a computed tomography (CT) scan with contrast due to the risk of contrast-induced nephropathy (CIN). These patients could alternatively be imaged by magnetic resonance imaging (MRI) with gadolinium. However, the recent identification of the association between nephrogenic systemic fibrosis (NSF) and gadolinium administration has created significant challenges for urologists and radiologists when faced with the need for evaluation with contrast-enhanced cross-sectional imaging. In this review, we summarize the most comprehensive articles discussing both NSF and CIN and present a straightforward, evidence-based algorithm to determine the appropriate approach to cross-sectional imaging for all patients, as well as future directions regarding cross-sectional imaging. MATERIALS AND METHODS: A MEDLINE literature search for review articles from 1966 to August 2009 was performed. Selected additional articles for specific topics were also reviewed. This search yielded a total of 25 articles for NSF and 28 for CIN that were reviewed. RESULTS: The pathophysiology and risk factors of NSF and CIN are discussed, as well as potential interventions to decrease either morbidity or incidence. A multidisciplinary (urologist, nephrologist, radiologist) evidence-based algorithm is introduced for managing patients in need of cross-sectional imaging. CONCLUSIONS: The associated risks of contrast-enhanced, cross-sectional imaging has created significant challenges for urologic evaluation. We propose an evidence-based approach to guide patient therapy, which can minimize patient risk and physician anxiety, while simplifying the decision-making process.

Congenital extrahepatic portosystemic shunt (Abernethy malformation) treated endovascularly with vascular plug shunt closure.

A 3-year-old boy, who presented with progressive cyanosis and hypoxia, was diagnosed with a large congenital extrahepatic portosystemic shunt, interrupted IVC with azygos continuation, and multiple congenital anomalies. Traditionally open and laparoscopic surgical techniques have been used to treat this malformation. Endovascular repair using a 16-mm Amplatzer vascular plug (AGA Medical Corporation, Golden Valley, Minnesota, USA) was used to occlude the shunt. Immediate post-placement venography demonstrated cessation of flow within the shunt and increased portal venous flow. The patient's hypoxia and cyanosis decreased significantly, and he was discharged on the 5th post-procedure day in stable clinical condition. Three months follow-up evaluation demonstrated the vascular plug in place, unchanged in position.

Temporal assessment of splenic function in patients who have undergone percutaneous image-guided splenic artery embolization in the setting of trauma.

PURPOSE: The role of transcatheter splenic arterial embolization (SAE) in the nonoperative management of splenic injury is evolving. The purpose of this study is to evaluate patients who have undergone SAE for laboratory markers of hyposplenism in the years after their procedure. MATERIALS AND METHODS: Thirty-four subjects who had undergone SAE as part of nonoperative management of splenic trauma during a period of 10 years were included. A blood sample was collected from each patient for complete blood count and smear analysis for peripheral markers of hyposplenism (as indicated by Howell-Jolly bodies [HJBs]). Sample size and power analysis was performed, and likelihoods for various true prevalences were calculated. RESULTS: The average time interval from procedure to follow-up was 4.4 years. No participants had peripheral markers of hyposplenism or abnormalities in cell count on follow-up. CONCLUSIONS: Phagocytic function of the spleen in patients who have undergone SAE is preserved, as evidenced by the absence of HJBs on follow-up peripheral blood smears.

Applications of time-resolved MR angiography.

OBJECTIVE: The purpose of this essay is to describe the basic principles behind contrast-enhanced time-resolved MR angiography (MRA) performed with the time-resolved imaging with stochastic trajectories technique and to show examples of the versatile applications of this technique in the evaluation of pathologic conditions throughout the body. CONCLUSION: Time-resolved MR angiography is a versatile technique for vascular imaging throughout the body. It can be used to answer a variety of clinical questions; to acquire diagnostically useful information, even about complicated vascular lesions; and to overcome many of the limitations of bolus-chase contrast-enhanced MR angiography. The technique is particularly useful when the arterial arrival time is uncertain, the patient is freely breathing, or contrast dynamics are critical to a diagnosis.

Cryoablation vs. radiofrequency ablation for small renal masses.

RATIONALE AND OBJECTIVES: Cancer of the kidney is the third most common cancer of the urinary tract, and renal cell carcinoma is the most lethal of all genitourinary tumors. The incidental discovery of renal cell carcinoma has increased with increased use of cross-sectional imaging. Concomitantly, minimally invasive ablative technologies, including image-guided cryoablation, radiofrequency ablation, and others, have evolved as therapeutic options for small renal masses. MATERIALS AND METHODS: Between 2006 and 2009, 111 patients (age range, 31-91 years; mean age, 70 years) underwent percutaneous computed tomography-guided thermal ablation for suspected renal cell carcinoma at two major academic centers. Outcomes data were retrospectively collected and analyzed to compare recurrence rates for patients undergoing radiofrequency ablation (n = 41) versus cryoablation (n = 70). RESULTS: There were four cases of suspicious enhancement on follow-up computed tomography or magnetic resonance imaging in each group, with cumulative imaging recurrence rates of 11% and 7% for radiofrequency ablation and cryoablation, respectively. Log rank test analysis revealed no significant difference between rates of imaging recurrence between the two groups (P = .6044). CONCLUSIONS: These results suggest that the use of cryoablative technology will result in similar outcomes compared with radiofrequency ablation.