Yttrium-90 Radioembolization to the Prostate Gland: Proof of Concept in a Canine Model and Clinical Translation.

Purpose: To investigate the feasibility, safety, and absorbed-dose distribution of prostatic artery radioembolization (RE) in a canine model.

Materials And Methods: Fourteen male castrated beagles received dihydroandrosterone/estradiol to induce prostatic hyperplasia for the duration of the study. Each dog underwent fluoroscopic prostatic artery catheterization.

Correction to: Yttrium-90 radioembolization as a possible new treatment for brain cancer: proof of concept and safety analysis in a canine model.

An amendment to this paper has been published and can be accessed via the original article.

Yttrium-90 radioembolization as a possible new treatment for brain cancer: proof of concept and safety analysis in a canine model.

Purpose: To evaluate the safety, feasibility, and preliminary efficacy of yttrium-90 (Y) radioembolization (RE) as a minimally invasive treatment in a canine model with presumed spontaneous brain cancers.

Materials: Three healthy research dogs (R1-R3) and five patient dogs with spontaneous intra-axial brain masses (P1-P5) underwent cerebral artery RE with Y glass microspheres (TheraSphere). Y-RE was performed on research dogs from the unilateral internal carotid artery (ICA), middle cerebral artery (MCA), and posterior cerebral artery (PCA) while animals with brain masses were treated from the ICA.

The number of microspheres in Y90 radioembolization directly affects normal tissue radiation exposure.

Purpose: In Y90 radioembolization, the number of microspheres infused varies by more than a factor of 20 over the shelf-life of the glass radioembolization device. We investigated the effect of the number of Y90 microspheres on normal liver tissue.

Method: Healthy pigs received lobar radioembolization with glass Y90 microspheres at 4, 8, 12, and 16 days post-calibration, representing a > 20× range in the number of microspheres deposited per milliliter in tissue.

Verification of a method to detect glass microspheres via micro-CT.

Introduction: The ability to determine the microscopic distribution of glass microspheres in Y radioembolization has important applications in post-treatment microdosimetry and cluster analysis. Current methods are time-intensive and labor-intensive and thus are typically only applied to small samples.

Materials And Methods: A high-resolution micro-CT image with a voxel size of 8.

Impact of using scatter-mimicking beams instead of standard beams to measure penetration when assessing the protective value of radiation-protective garments.

Purpose: Use standardized methods to determine how assessment of protective value of radiation-protective garments changes under conditions employing standard beam qualities, scatter-mimicking primary beams, and a modified H (10) measurement.

Methods: The shielding properties of radiation-protective garments depend on the spectrum of beam energies striking the garment and the attenuation properties of materials used to construct the garment, including x-ray fluorescence produced by these materials. In this study the primary beam spectra employed during clinical interventional radiology and cardiology procedures (clinical primary beams, CPB) were identified using radiation dose structured reports (RDSR) and fluoroscope log data.

Computational simulation of the predicted dosimetric impact of adjuvant yttrium-90 PET/CT-guided percutaneous ablation following radioembolization.

Background: Y PET/CT post-radioembolization imaging has demonstrated that the distribution of Y in a tumor can be non-uniform. Using computational modeling, we predicted the dosimetric impact of post-treatment Y PET/CT-guided percutaneous ablation of the portions of a tumor receiving the lowest absorbed dose. A cohort of fourteen patients with non-resectable liver cancer previously treated using Y radioembolization were included in this retrospective study.

Bariatric Radioembolization: A Pilot Study on Technical Feasibility and Safety in a Porcine Model.

Purpose: To evaluate feasibility of left gastric artery (LGA) yttrium-90 ((90)Y) radioembolization as potential treatment for obesity in a porcine model.

Materials And Methods: This study included 8 young female pigs (12-13 weeks, 21.8-28.

How Sensitive Is the Upper Gastrointestinal Tract to 90Y Radioembolization? A Histologic and Dosimetric Analysis in a Porcine Model.

Unlabelled: In Y radioembolization, nontarget embolization to the stomach or small bowel can result in gastrointestinal injury, a rare but difficult to manage clinical complication. However, dosimetric thresholds for toxicity to these tissues from radioembolization have never been evaluated in a controlled setting. We performed an analysis of the effect of Y radioembolization in a porcine model at different absorbed-dose endpoints.

Sensitivity of the diagnostic radiological index of protection to procedural factors in fluoroscopy.

Purpose: To evaluate the sensitivity of the diagnostic radiological index of protection (DRIP), used to quantify the protective value of radioprotective garments, to procedural factors in fluoroscopy in an effort to determine an appropriate set of scatter-mimicking primary beams to be used in measuring the DRIP.

Methods: Monte Carlo simulations were performed to determine the shape of the scattered x-ray spectra incident on the operator in different clinical fluoroscopy scenarios, including interventional radiology and interventional cardiology (IC). Two clinical simulations studied the sensitivity of the scattered spectrum to gantry angle and patient size, while technical factors were varied according to measured automatic dose rate control (ADRC) data.

A Microdosimetric Analysis of Absorbed Dose to Tumor as a Function of Number of Microspheres per Unit Volume in 90Y Radioembolization.

Unlabelled: Differences in maximum tolerable absorbed dose to normal liver between (90)Y radioembolization and external-beam radiation therapy have been explained by citing differences in absorbed-dose heterogeneity at the microscopic level. We investigated microscopic absorbed-dose heterogeneity in radioembolization as a function of the number of microspheres per unit volume in tumor. The goal was to determine what effect the number of microspheres may have, if any, on tumor control in (90)Y radioembolization.

Safety and efficacy of combined micropuncture and shallow angle femoral artery access for neurovascular angiography.

Introduction: The AXERA 2 low-angle vascular access device utilizes a dual arteriotomy mechanism in which the standard access tract is compressed by a vascular sheath inserted over the second, low-angle tract. It is unknown whether this device could be effectively used with 21-gauge micropuncture access, as the micropuncture introducer makes a larger arteriotomy than the 19-gauge needle provided with the AXERA 2 system.

Materials And Methods: A retrospective review was performed on 189 patients who underwent common femoral artery access for diagnostic cerebrovascular angiography using either combined micropuncture and AXERA 2 access or standard access with manual pressure hemostasis.

The evolution of image-guided lumbosacral spine surgery.

Techniques and approaches of spinal fusion have considerably evolved since their first description in the early 1900s. The incorporation of pedicle screw constructs into lumbosacral spine surgery is among the most significant advances in the field, offering immediate stability and decreased rates of pseudarthrosis compared to previously described methods. However, early studies describing pedicle screw fixation and numerous studies thereafter have demonstrated clinically significant sequelae of inaccurate surgical fusion hardware placement.

Simulation-based educational curriculum for fluoroscopically guided lumbar puncture improves operator confidence and reduces patient dose.

Rationale And Objectives: Fluoroscopically guided lumbar puncture (FGLP) is a commonly performed procedure with increased success rates relative to bedside technique. However, FGLP also exposes both patient and staff to ionizing radiation. The purpose of this study was to determine if the use of a simulation-based FGLP training program using an original, inexpensive lumbar spine phantom could improve operator confidence and efficiency, while also reducing patient dose.

The impact of an antireflux catheter on target volume particulate distribution in liver-directed embolotherapy: a pilot study.

Purpose: To determine if there are differences in hepatic distribution of embolic particles following infusion with a standard end-hole catheter versus an antireflux microcatheter.

Materials And Methods: This prospective study included nine patients (age, 48-86 y) enrolled for treatment of hepatocellular carcinoma (n = 6), liver-dominant metastatic disease (n = 2), or intrahepatic cholangiocarcinoma (n = 1) with resin yttrium-90 ((90)Y) microspheres. Before (90)Y treatment, each patient received two same-day sequential lobar infusions of technetium 99m ((99m)Tc) macroaggregated albumin (MAA) via a conventional end-hole catheter and an antireflux microcatheter positioned at the same location.

Application of the diagnostic radiological index of protection to protective garments.

Purpose: Previously, the diagnostic radiological index of protection (DRIP) was proposed as a metric for quantifying the protective value of radioprotective garments. The DRIP is a weighted sum of the percent transmissions of different radiation beams through a garment. Ideally, the beams would represent the anticipated stray radiation encountered during clinical use.

Application of the diagnostic radiological index of protection to protective garments.

Purpose: Previously, the diagnostic radiological index of protection (DRIP) was proposed as a metric for quantifying the protective value of radioprotective garments. The DRIP is a weighted sum of the percent transmissions of different radiation beams through a garment. Ideally, the beams would represent the anticipated stray radiation encountered during clinical use.

A robust and inexpensive phantom for fluoroscopically guided lumbar puncture training.

Introduction: This report describes the creation process for an inexpensive, durable, lumbar spine phantom for use in fluoroscopically guided lumbar puncture (LP) training.

Methods: The LP phantom prototype was made from a polyvinyl chloride lumbar spine model embedded in a translucent rectangular block of commercially available thermoplastic polymer gel. Radiology residents with limited previous experience performing LP used the phantom for 20 simulated procedures to gain confidence before starting patient procedures.

C-arm rotation as a method for reducing peak skin dose in interventional cardiology.

Purpose: Prolonged interventional cardiology (IC) procedures may result in radiation-induced skin injury, a potentially preventable cause of patient morbidity. Rotating the C-arm during an IC procedure may reduce this risk, although the methods by which the technique can be practically applied remains unexplored. A previous study demonstrated that C-arm rotation often increases peak skin dose (PSD) in interventional radiology procedures.

Time to take the gloves off: the use of radiation reduction gloves can greatly increase patient dose.

Sterile radiation reduction gloves have been widely used over the past several decades in an effort to reduce hand doses during fluoroscopically guided proce- dures. While multiple studies have quantified the potential dose reduction to the fluoroscope operator from the use of such gloves, possible effects on the patient have not yet been quantified. The aim of this study was to examine the impact on patient dose when radiation reduction gloves are used.

Improved Accuracy of Minimally Invasive Transpedicular Screw Placement in the Lumbar Spine With 3-Dimensional Stereotactic Image Guidance: A Comparative Meta-Analysis.

Study Design: This study compares the accuracy rates of lumbar percutaneous pedicle screw placement (PPSP) using either 2-dimensional (2-D) fluoroscopic guidance or 3-dimensional (3-D) stereotactic navigation in the setting of minimally invasive spine surgery (MISS). This represents the largest single-operator study of its kind and first comprehensive review of 3-D stereotactic navigation in the setting of MISS.

Objective: To examine differences in accuracy of lumbar pedicle screw placement using 2-D fluoroscopic navigation and 3-D stereotaxis in the setting of MISS.

How accurately can the peak skin dose in fluoroscopy be determined using indirect dose metrics?

Purpose: Skin dosimetry is important for fluoroscopically-guided interventions, as peak skin doses (PSD) that result in skin reactions can be reached during these procedures. There is no consensus as to whether or not indirect skin dosimetry is sufficiently accurate for fluoroscopically-guided interventions. However, measuring PSD with film is difficult and the decision to do so must be madea priori.