Randy O. Chang

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.

Drill-Assisted Biopsy of the Axial and Appendicular Skeleton: Safety, Technical Success, and Diagnostic Efficacy

The purpose of this study was to evaluate the safety, technical success rate, and diagnostic efficacy of drill-assisted axial and appendicular bone biopsies. During a 3-y period, 703 drill-assisted biopsies were performed. The cohort included 54.2% men, with a mean age of 57.6 y ± 17.1. Median lesion volume was 10.9 mL (interquartile range, 3.4-30.2 mL). Lesions were lytic (31.7%), sclerotic (21.2%), mixed lytic and sclerotic (27.7%), or normal radiographic bone quality (19.3%). No complications were reported. The technical biopsy success rate was 99.9%. Crush artifact was present in 5.8% of specimens submitted for surgical pathologic examination, and 2.1% of specimens were inadequate for histologic evaluation.

Delayed vertebral body collapse after stereotactic radiosurgery and radiofrequency ablation: Case report with histopathologic-MRI correlation.

Stereotactic radiosurgery and percutaneous radiofrequency ablation are emerging therapies for pain palliation and local control of spinal metastases. However, the post-treatment imaging findings are not well characterized and the risk of long-term complications is unknown. We present the case of a 46-year-old woman with delayed vertebral body collapse after stereotactic radiosurgery and radiofrequency ablation of a painful lumbar metastasis. Histopathologic-MRI correlation confirmed osteonecrosis as the underlying etiology and demonstrated that treatment-induced vascular fibrosis and tumor progression can have identical imaging appearances.

Neuroimaging Features of Idiopathic Intracranial Hypertension Persist After Resolution of Papilloedema

ABSTRACT Papilloedema is a key clinical finding in the diagnosis of idiopathic intracranial hypertension (IIH). However, newly proposed criteria allow diagnosis without papilloedema only if certain neuroimaging features are present. It is currently unclear if these findings persist upon resolution of papilloedema and IIH. A retrospective chart review identified three groups of patients (six per group) who had received orbital imaging within 4 weeks of fundoscopic examination: (1) IIH patients without active papilloedema, (2) IIH patients with active papilloedema, and (3) patients with no history of IIH or papilloedema. All magnetic resonance imaging (MRI) scans were graded by a neuroradiologist who was blinded to clinical status. Neuroimaging features were compared by using the Kruskal-Wallis one-way analysis of variance. Measurements of sellar and optic nerve configuration showed a statistical trend with papilloedema status. For the control group versus the active papilloedema group, the values were 0.0597 and 0.0621, respectively. For the control group versus the resolved papilloedema group, the values were 0.0485 and 0.0512, respectively. However, globe and sellar p values for the resolved papilloedema group versus the active papilloedema group were 1.000 and 0.6023, respectively, and not significant. Sellar and globe configuration suggest that a statistical trend for persistence after papilloedema has resolved and intracranial pressure (ICP) has normalised. Careful clinical correlation and fundus examination are essential because some of these neuroimaging features can be seen in normal patients and those with resolved IIH, and their presence on MRI may not necessarily indicate active disease or elevated ICP.

Drill-assisted, fluoroscopy-guided vertebral body access for radiofrequency ablation: Technical case series.

Radiofrequency ablation is a valuable therapy for palliation of painful spinal metastases and local tumor control; however, accessing the vertebral body can be difficult and time consuming with traditional manual needles. Herein, we report our initial experience using a drill-assisted, fluoroscopy-guided technique for accessing the vertebral body for radiofrequency ablation.

CT-guided percutaneous skull biopsy using a drill-assisted system: Technical report of two cases

The OnControl coaxial biopsy system (Vidacare Corporation, Shavano Park, TX) includes an inner diamond-tipped access needle and hollow biopsy needle that engage with a battery-powered hand drill. Herein, we report the use of this novel device to perform two CT-guided percutaneous skull biopsies. Both procedures were performed without complication and facilitated a pathologic diagnosis.

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.

Correction to: Treatment of Osteoid Osteomas Using a Navigational Bipolar Radiofrequency Ablation System

In “Radiofrequency Ablation Procedure” section of the original article, the relationship between the location of the thermocouples and the size of the ablation zones is inaccurate and not consistent with the referenced article in the bibliography (#3. Hillen et al).