Osteoid osteoma in older adults: clinical success rate of percutaneous image-guided thermal ablation.

AIM: To assess the clinical success rate of percutaneous radiofrequency and laser ablation of osteoid osteomas in older adults. MATERIALS AND METHODS: Percutaneous radiofrequency or laser ablation was performed in 43 patients (35 years and older) with osteoid osteoma to achieve definitive cure in this retrospective study. The clinical success rate was defined as complete pain relief determined by numeric rating scale (NRS) scores (pre-procedural and post-procedural at 1-week, 6-week, and 2-year intervals). Tumour characteristics, technical success, procedural details, biopsy results, and complications were documented. RESULTS: Forty-four osteoid osteomas were ablated in 43 patients, and all procedures were technically successful. The clinical success rates were 95.2% (41/43), 93% (40/43), and 93.2% (41/44) at 1-week, 6-week, and 2-year post-procedural intervals. The acute complication rate was 2.3% (1/44; meningeal perforation following epidural anaesthesia). No delayed complication was documented. CONCLUSION: Osteoid osteomas are not unique to the paediatric and young population, and safe and effective definitive treatment of these benign tumours in older adults can be achieved by percutaneous radiofrequency and laser ablation with excellent patient outcomes.

Percutaneous CT-Guided Skull Biopsy: Feasibility, Safety, and Diagnostic Yield.

BACKGROUND AND PURPOSE: Although percutaneous musculoskeletal biopsies are routinely performed in the axial and appendicular skeleton, there are no published data on the systematic evaluation of the feasibility, safety, and diagnostic accuracy of percutaneous skull biopsy. In certain clinical encounters such as patients with primary skull tumors or patients with known cancer and isolated skull lesions suspected of calvarial metastasis or synchronous primary tumor, percutaneous skull biopsy may be considered a viable option. The purpose of this study was to evaluate the feasibility, safety profile, and diagnostic yield of percutaneous CT-guided skull biopsy. MATERIALS AND METHODS: Percutaneous CT-guided skull biopsy was performed in 14 patients. Patient demographics, cancer history, indication for initial imaging, imaging technique of diagnosis, skull tumor anatomic location, and final histologic diagnosis were documented. Preprocedural imaging of each skull lesion was reviewed to determine tumor size and characteristics. Procedural notes were reviewed to determine the total conscious sedation time or anesthesia time, type of biopsy needle, and the number and length of obtained core specimens. Procedure-related complications were also documented according to the Society of Interventional Radiology classification. RESULTS: All CT-guided percutaneous skull biopsy procedures were performed as preoperatively planned and were technically successful. Procedures were performed with the patient under conscious sedation in 93% (13/14) of cases. Definitive histologic diagnosis was achieved in 86% (12/14) of cases. There were no acute or delayed procedure-related complications. CONCLUSIONS: The results of this retrospective initial study suggest that percutaneous CT-guided skull biopsy is feasible with an excellent safety profile, affords a high diagnostic yield for histologic characterization, and may obviate more invasive open skull biopsies.

Percutaneous Radiofrequency Ablation of Spinal Osteoid Osteomas Using a Targeted Navigational Bipolar Electrode System.

Safe and effective percutaneous CT-guided radiofrequency ablation of spinal osteoid osteomas can be performed using a targeted navigational bipolar electrode system. Articulating bipolar electrodes with built-in thermocouples along an electrode shaft and variable generator wattage settings allow optimal nidus access, particularly in challenging locations; provide precise real-time monitoring of ablation zone volume and geometry; and minimize the risk of undesired thermal injury.

Simultaneous Bipedicular Radiofrequency Ablation Combined with Vertebral Augmentation for Local Tumor Control of Spinal Metastases.

BACKGROUND AND PURPOSE: Percutaneous radiofrequency ablation combined with vertebral augmentation has emerged as a minimally invasive treatment for patients with vertebral metastases who do not respond to or have contraindications to radiation therapy. The prevalence of posterior vertebral body metastases presents access and treatment challenges in the unique anatomy of the spine. The purpose of this study was to evaluate the safety and efficacy of simultaneous bipedicular radiofrequency ablation using articulating bipolar electrodes combined with vertebral augmentation for local tumor control of spinal metastases. MATERIALS AND METHODS: Imaging-guided simultaneous bipedicular radiofrequency ablation combined with vertebral augmentation was performed in 27 patients (33 tumors) with vertebral metastases selected following multidisciplinary consultations, to achieve local tumor control in this retrospective study. Tumor characteristics, procedural details, and complications were documented. Pre- and postprocedural cross-sectional imaging was evaluated to assess local tumor control rates. RESULTS: Thirty-three tumors were successfully ablated in 27 patients. Posterior vertebral body or pedicle involvement or both were present in 94% (31/33) of cases. Sixty-seven percent (22/33) of the tumors involved ≥75% of the vertebral body volume. Posttreatment imaging was available for 79% (26/33) of the treated tumors. Local tumor control was achieved in 96% (25/26) of tumors median imaging follow up of 16 weeks. No complications were reported, and no patients had clinical evidence of metastatic spinal cord compression at the treated levels. CONCLUSIONS: Simultaneous bipedicular radiofrequency ablation combined with vertebral augmentation is safe and effective for local tumor control of vertebral metastases. Articulating bipolar electrodes enable the placement and proximity necessary for optimal confluence of the ablation zones. Local tumor control may lead to more durable pain palliation, prevent disease progression, and reduce skeletal-related events of the spine.

Benign Spine Lesions: Advances in Techniques for Minimally Invasive Percutaneous Treatment.

Minimally invasive percutaneous imaging-guided techniques have been shown to be safe and effective for the treatment of benign tumors of the spine. Techniques available include a variety of tumor ablation technologies, including radiofrequency ablation, cryoablation, microwave ablation, alcohol ablation, and laser photocoagulation. Vertebral augmentation may be performed after ablation as part of the same procedure for fracture stabilization or prevention. Typically, the treatment goal in benign spine lesions is definitive cure. Painful benign spine lesions commonly encountered in daily practice include osteoid osteoma, osteoblastoma, vertebral hemangioma, aneurysmal bone cyst, Paget disease, and subacute/chronic Schmorl node. This review discusses the most recent advancement and use of minimally invasive percutaneous therapeutic options for the management of benign spine lesions.

Spine Cryoablation: Pain Palliation and Local Tumor Control for Vertebral Metastases.

BACKGROUND AND PURPOSE: Percutaneous cryoablation has emerged as a minimally invasive technique for the management of osseous metastases. The purpose of this study was to assess the safety and effectiveness of percutaneous imaging-guided spine cryoablation for pain palliation and local tumor control for vertebral metastases. MATERIALS AND METHODS: Imaging-guided spine cryoablation was performed in 14 patients (31 tumors) with vertebral metastases refractory to conventional chemoradiation therapy or analgesics, to achieve pain palliation and local tumor control in this retrospective study. Spinal nerve and soft-tissue thermal protection techniques were implemented in all ablations. Patient response was evaluated by a pain numeric rating scale administered before the procedure and 1 week, 1 month, and 3 months after the procedure. Pre- and postprocedural analgesic requirements (expressed as morphine-equivalent dosages) were also analyzed at the same time points. Pre- and postprocedural cross-sectional imaging was evaluated in all patients to assess local control (no radiographic evidence of disease at the treated sites). Complications were monitored. Analysis of the primary end points was undertaken via paired-comparison procedures by using the Wilcoxon signed rank test. RESULTS: Thirty-one tumors were ablated in 14 patients (9 women and 5 men; 20-73 years of age; mean age, 53 years). The most common tumor location was in the lumbar spine (n = 14, 45%), followed by the thoracic spine (n = 8, 26%), sacrum (n = 6, 19%), coccyx (n = 2, 6%), and cervical spine (n = 1, 3%). There were statistically significant decreases in the median numeric rating scale score and analgesic usage at 1-week, 1-month, and 3-month time points (P < .001 for all). Local tumor control was achieved in 96.7% (30/31) of tumors (median follow-up, 10 months). Two patients had transient postprocedural unilateral lower extremity radiculopathy and weakness. CONCLUSIONS: Percutaneous imaging-guided spine cryoablation is a safe and effective treatment for pain palliation and local tumor control for vertebral metastases.

Radiographic Local Control of Spinal Metastases with Percutaneous Radiofrequency Ablation and Vertebral Augmentation.

BACKGROUND AND PURPOSE: Combination radiofrequency ablation and vertebral augmentation is an emerging minimally invasive therapy for patients with metastatic spine disease who have not responded to or have contraindications to radiation therapy. The purpose of this study was to evaluate the rate of radiographic local control of spinal metastases treated with combination radiofrequency ablation and vertebral augmentation. MATERIALS AND METHODS: We retrospectively reviewed our tumor ablation database for all patients who underwent radiofrequency ablation and vertebral augmentation of spinal metastases between April 2012 and July 2014. Tumors treated in conjunction with radiation therapy were excluded. Tumor characteristics, procedural details, and complications were recorded. Posttreatment imaging was reviewed for radiographic evidence of tumor progression. RESULTS: Fifty-five tumors met study inclusion criteria. Radiographic local tumor control rates were 89% (41/46) at 3 months, 74% (26/35) at 6 months, and 70% (21/30) at 1 year after treatment. Clinical follow-up was available in 93% (51/55) of cases. The median duration of clinical follow-up was 34 weeks (interquartile range, 15-89 weeks), during which no complications were reported and no patients had clinical evidence of metastatic spinal cord compression at the treated levels. CONCLUSIONS: Combination radiofrequency ablation and vertebral augmentation appears to be an effective treatment for achieving local control of spinal metastases. A prospective clinical trial is now needed to replicate these results.

3D high-spatial-resolution cerebral MR venography at 3T: a contrast-dose-reduction study.

BACKGROUND AND PURPOSE: The effect of various contrast-dose regimens for cerebral MR venography (MRV) has not been previously evaluated at 3T, to our knowledge. Our purpose was to evaluate and compare the diagnostic image quality resulting from half-versus-full-dose contrast regimens for high-spatial-resolution 3D cerebral MRV at 3T. MATERIALS AND METHODS: Forty consecutive patients with known or suggested cerebrovascular disease underwent 3D high-spatial-resolution (0.7 x 0.6 x 0.9 mm(3)) cerebral contrast-enhanced MRV (CE-MRV) at 3T, by using an identical acquisition protocol. Patients were assigned to 1 of 2 groups: 1) full-dose (approximately 0.1 mmol/kg), and 2) half-dose (approximately 0.05 mmol/kg). Two readers evaluated the resulting images for overall image quality, venous structure definition, and arterial contamination. Signal intensity-to-noise-ratio (SNR) and contrast-to-noise-ratio (CNR) were evaluated in 8 consistent sites. Statistical analysis was performed by using Mann-Whitney U, Wilcoxon signed rank, and t tests and a kappa coefficient. RESULTS: Both readers scored venous-structure definition as excellent or sufficient for diagnosis in approximately 90% of segments for the full-dose group (kappa = 0.87) and in approximately 80% of segments for the half-dose group (kappa = 0.85). Delineation grades were significantly lower for small venous segments, including the middle cerebral, septal, superior cerebellar, inferior vermian, posterior tonsillar, and thalamostriate veins in the half-dose group (P < .01). No significant difference existed for arterial contamination grades between the 2 groups (P > .05). SNR and CNR values were lower in the half-dose group (P < .01). CONCLUSIONS: At 3T, high-spatial-resolution cerebral MRV can be performed with contrast doses as low as 7.5 mL, without compromising image quality as compared with full-dose protocols, except in the smallest veins, and without compromise of acquisition speed or spatial resolution.

Coronary artery to pulmonary artery fistulae with multiple aneurysms: radiological features on dual-source 64-slice CT angiography.

Coronary artery fistula is a rare vascular anomaly in which there is abnormal communication between the coronary artery and the great vessels or cardiac chambers. We report the case of a 66-year-old man with two separate coronary artery to pulmonary artery fistulas (one of which demonstrated multiple aneurysms), which were diagnosed on dual-source 64-slice coronary CT and reconfirmed by coronary catheter angiography.

CT-guided percutaneous transpulmonary adrenal biopsy - a technical note.

CT-guided percutaneous adrenal biopsy is commonly performed using a posterior or trans-abdominal approach. However, trans-abdominal access to the gland may not be technically feasible in some patients. In our case, CT-guided transthoracic percutaneous biopsy of the adrenal gland was performed with technical success, identifying the tumour. To the best of our knowledge, there has been no previous case describing this transpulmonary approach in the literature.

Low-dose, time-resolved, contrast-enhanced 3D MR angiography in cardiac and vascular diseases: correlation to high spatial resolution 3D contrast-enhanced MRA.

AIM: To evaluate the effectiveness of low-dose, contrast-enhanced, time-resolved, three-dimensional (3D) magnetic resonance (MR) angiography (TR-MRA) in the assessment of various cardiac and vascular diseases, and to compare the results with high-resolution contrast-enhanced MRA (CE-MRA). MATERIALS AND METHODS: Thirty consecutive patients underwent contrast-enhanced 3D TR-MRA and high spatial resolution 3D CE-MRA for evaluation of cardiac and thoracic vascular diseases at 1.5 T, and neurovascular, abdominal and peripheral vascular diseases at 3T. Gadolinium-based contrast medium was administered at a constant dose of 5 ml for TR-MRA, and 20 ml (lower extremity 30 ml) for CE-MRA. Two readers evaluated image quality using a four-point scale (from 0=excellent to 3=non-diagnostic), artefacts and findings on both datasets. Interobserver variability was tested with kappa coefficient. RESULTS: The overall image quality for TR-MRA was in the diagnostic range (median 0, range 0-1; k=0.74). Readers demonstrated important additional dynamic information on TR-MRA in 28 of 30 patients (k=0.84). Confident evaluation of organ perfusion (n=23), arteriovenous malformation/fistula flow patterns (n=7), exclusion of intra-cardiac shunts (n=6), and assessment of stent and conduit patency (n=5) were performed by both readers using TR-MRA. Readers demonstrated fine vascular details with higher confidence in 10 patients on CE-MRA. Using CE-MRA, Reader 1 and 2 depicted anatomical details in 6 and 5 patients, respectively, only on CE-MRA. CONCLUSION: Low-dose TR-MRA yields rapid and important functional and anatomical information in patients with cardiac and vascular diseases. Due to limited spatial resolution, TR-MRA is inferior to CE-MRA in demonstrating fine vascular details.

Left ventricular ejection fraction using 64-slice CT coronary angiography and new evaluation software: initial experience.

The purpose of this study was to evaluate the feasibility and reliability of software-based quantification of left ventricular function using 64-slice CT coronary angiography. Data were collected from 26 subjects who underwent a 64-slice coronary CT angiography study. Two volumetric data sets at end diastole and end systole were reconstructed from each scan by means of retrospective electrocardiogram gating. Data sets were evaluated with a prototype of now commercially available software (Syngo Circulation I; Siemens Medical Solutions, Erlangen, Germany), which automatically segments the blood volume in the left ventricle after the user defines the mitral valve plane and any point within the ventricle. After segmentation of the blood pool in end systole and end diastole, the software automatically measures end systolic and end diastolic volume and calculates stroke volume and ejection fraction (EF). Two readers processed all CT data sets twice to assess for intra- and inter-observer variation. In addition, CT EF measurements were compared with those obtained by clinical echocardiography. Intra-observer variation for the calculated EF with CT were 13.6% and 15.6% for Readers 1 and 2, respectively. No significant difference in left ventricular functional parameters on CT existed between the readers (p > 0.05). A Bland-Altman plot revealed a slight mean difference between EF measurements on CT and echocardiography, with all differences falling within two standard deviations of the mean in the setting of wide limits of agreement. In conclusion, assessment of left ventricular EF from CT coronary data using the new analysis software is rapid and easy. The software is user-friendly and provides good reproducibility for EF measurements with CT.

Percutaneous osteoid osteoma treatment with combination of radiofrequency and alcohol ablation.

AIM: To assess the efficacy of percutaneous osteoid osteoma treatment using a combination of radiofrequency ablation (RFA) and alcohol ablation with regard to technical and long-term clinical success. MATERIALS AND METHODS: From December 2001 to November 2004, RFA and subsequent alcohol ablation was performed on 54 patients with osteoid osteoma, diagnosed clinically using radiography, computed tomography (CT) and symptoms. Under general anaesthesia, treatment was performed via percutaneous access under thin section (2mm) spiral CT guidance in all cases with an 11 G radiofrequency-compatible coaxial needle and 2mm coaxial drill system and 1.0 cm active tip 17 G non-cooled radiofrequency needle. RFA was performed at 90 degrees C for a period of 6 min. After needle removal, 0.5-1.0 ml absolute alcohol (99.8% concentration) was injected directly into the nidus using a 20 G needle. Patients were discharged within 24h and followed up clinically (at 1 week, 1 month and every 3 months thereafter). RESULTS: The technical success rate was 100%. Complications occurred in two patients consisting of local mild cellulitis in entry site and peripheral small zone paresthesia on the anterior part of leg. The follow-up period range was 13-48 months (mean+/-SD, 28.2+/-7.4 months). Prompt pain relief and return to normal activities were observed in 52 of 54 patients. Recurrent pain occurred in two patients after a 1 and 3 months period of being pain free, respectively; a second RFA and alcohol ablation was performed achieving successful results. Primary and secondary clinical success rates were 96.3% (52/54 patients) and 100% (2/2 patients), respectively. CONCLUSION: Percutaneous osteoid osteoma treatment with combination of radiofrequency and alcohol ablation is safe, effective and minimally invasive with high primary and secondary success rates. Persistent or recurrent lesions can be effectively re-treated.