Purpose: Radiofrequency (RF) ablation is the targeted damage of neural tissues to disrupt pain transmission in sensory nerves using thermal energy generated in situ by an RF probe. The present study aims to evaluate the utility of magnetic resonance imaging (MRI) for in vivo quantitative assessment of ablation zones in human subjects following cooled radiofrequency neurotomy for chronic pain at spinal facet or sacroiliac joints. Ablation zone size and shape have been shown in animal models to be influenced by size and type of RF probe - with cooled RF probes typically forming larger, more spherical ablation zones.
View Article and Find Full Text PDFPurpose To evaluate factors contributing to interreader variation (IRV) in parameters measured at dynamic contrast material-enhanced (DCE) MRI in patients with glioblastoma who were participating in a multicenter trial. Materials and Methods A total of 18 patients (mean age, 57 years ± 13 [standard deviation]; 10 men) who volunteered for the advanced imaging arm of ACRIN 6677, a substudy of the RTOG 0625 clinical trial for recurrent glioblastoma treatment, underwent analyzable DCE MRI at one of four centers. The 78 imaging studies were analyzed centrally to derive the volume transfer constant (K) for gadolinium between blood plasma and tissue extravascular extracellular space, fractional volume of the extracellular extravascular space (v), and initial area under the gadolinium concentration curve (IAUGC).
View Article and Find Full Text PDFBackground: ACRIN 6686/RTOG 0825 was a phase III trial of conventional chemoradiation plus adjuvant temozolomide with bevacizumab or without (placebo) in newly diagnosed glioblastoma. This study investigated whether changes in contrast-enhancing and fluid attenuated inversion recovery (FLAIR)-hyperintense tumor assessed by central reading prognosticate overall survival (OS).
Methods: Two hundred eighty-four patients (171 men; median age 57 y, range 19-79; 159 on bevacizumab) had MRI at post-op (baseline) and pre-cycle 4 of adjuvant temozolomide (22 wk post chemoradiation initiation).
Stereotact Funct Neurosurg
September 2017
Background: For Parkinson's disease (PD), essential tremor (ET), and dystonia patients with deep brain stimulation (DBS) implants, magnetic resonance imaging (MRI) requires additional safety considerations due to potentially hazardous interactions.
Objective: A propensity-matched cohort of DBS-implanted patients was analyzed to determine the likelihood of needing MRI.
Methods: Patients with new DBS full-system implants (n = 576) were identified in the Truven Health MarketScan® Commercial Claims and Medicare Supplemental Databases (2009-2012).