Comprehensive Palliative Musculoskeletal Interventional Radiology Care for Patients with Cancer.

Substantial advances in percutaneous image-guided minimally invasive musculoskeletal oncologic interventions offer a robust armamentarium for interventional radiologists for management of cancer. The authors outline the most recent advances in such interventions and the role of interventional radiologists in managing cancer in modern-era practice. Percutaneous minimally invasive musculoskeletal interventions including thermal ablation, cementation with or without osseous reinforcement by implants, osteosynthesis, neurolysis, and embolization, as well as palliative injections, have been successfully used by interventional radiologists to achieve durable, timely, safe, effective palliation in a multidisciplinary setting and have been progressively incorporated into the management paradigm for patients with cancer with musculoskeletal involvement. Familiarity with the described interventions and implementation of procedural safety measures, combined with integration of these procedures into clinical practice with the support of the National Comprehensive Cancer Network and the American College of Radiology, as well as continued technologic advances in procedural equipment design, will further enhance the role of interventional radiologists in cancer management. ©RSNA, 2022.

[Percutaneous tumor ablation]. / Destruction tumorale percutanée.

Percutaneous tumor ablation has faced a major growth in recent years with progressive expansion of clinical indications and subsequent adoption by national and international guidelines. Such techniques have become popular due to their minimally invasive profile and precise image-guided targeting resulting into a significant decrease of the procedure-related morbidity. Traditionally, malignant, and to lesser extent benign tumors, have been treated with these new techniques in several different organs including liver, kidney, lung and bone. More recently, other anatomic districts/organs including thyroid, breast, uterus and soft tissues have also been treated. Nevertheless, in order to optimize clinical results, precise knowledge of physical principles underlying these new techniques is of paramount importance, since technical adjustments may be provided according to specific tissue features (e.g. vascularization, density, etc.) and clinical indications of the procedure. Therefore, the goal of this review article is to present all the available ablation techniques with particular regard to their underlying physical principles and most common clinical indications.

Evaluation of occupational exposure to static magnetic field in MRI sites based on body pose estimation and SMF analytical computation.

This paper tackles the problem of estimating exposure to static magnetic field (SMF) in magnetic resonance imaging (MRI) sites using a non-invasive approach. The proposed approach relies on a vision-based system to detect people's body parts and on a mathematical model to compute SMF exposure. A multi-view camera system was used to capture the MRI room, and a vision-based system was applied to detect body parts. The detected localization was then fed into a mathematical model to compute SMF exposure. In this study, we focused on exposure at the neck due to two main reasons. First, according to regulations, the limit of exposure at head and trunk for MR workers is higher than that for the general public. Second, it was easier to attach a dosimeter at the neck to perform measurements, which allowed a quantitative evaluation of our approach. This approach was applied to two scenarios simulating the daily movements of medical workers for which dosimeter measurements were also recorded. The results indicated that the proposed approach predicted occupational SMF exposure with reasonable accuracy compared with the dosimeter measurements. The proposed approach is a simple safe working procedure to estimate the exposure of MR workers at different parts of the body without wearing any marker detection. It can be applied to reduce occupational SMF exposure, without changes in workers' performances. For that reason, our non-invasive proposed method can be used as a simple safety tool to estimate occupational SMF exposure in MR sites. Bioelectromagnetics. 39:503-515, 2018.© 2018 Wiley Periodicals, Inc.

Trans-rectal Ultrasound-Guided Autologous Blood Injection in the Interprostatorectal Space Prior to Percutaneous MRI-Guided Cryoablation of the Prostate.

OBJECTIVE: To report a novel technique of ultrasound-guided injection of autologous blood in the interprostatorectal space, in an attempt to facilitate ablative prostatic procedures by widening durably the space between the rectum and the prostate. MATERIALS AND METHODS: Between April and November 2016, four consecutive patients underwent the haemoprotection injection technique. For each patient, we recorded the time to perform the technique, the amount of injected blood, the achieved distances between the rectum and the prostate post-injection at fixed defined points (apex, middle, and base of prostate at the midline, left, and right sides of the gland), the extension of the ice ball outside the prostate capsule at those fixed points, and whether any residual blood was present on 1-month follow-up MRI. RESULTS: Mean time to perform haemoprotection injection was 54 min, with an average blood volume of 103 cc. Mean distance achieved at the apex, middle, and base of the prostate, respectively, was 12, 13, and 16 mm in the midline; 8, 10, and 13 mm on the left side; and 9, 10, and 13 mm on the right side. The mean extension distance of the ice ball beyond the capsule was 4, 6, and 6 mm in the midline; 4, 5, and 6 mm on the left side; and 1, 3, and 3 mm on the right side. No residual blood was present on 1-month follow-up MRI in all patients. No rectal fistula occurred. CONCLUSION: Haemoprotection may create a safe and effective virtual space between the prostate and rectum.

Percutaneous image-guided screws meditated osteosynthesis of impeding and pathological/insufficiency fractures of the femoral neck in non-surgical cancer patients.

AIM: To present percutaneous image-guided screw-mediated osteosynthesis (PIGSMO) for fixation of impending fractures (ImF) and non-displaced/mildly displaced pathological/insufficient fractures (PF/InF) of the femoral neck in non-surgical cancer patients. MATERIALS AND METHODS: This is a double-centre single-arm observational study. Retrospective review of electronic records identified all oncologic patients who had undergone femoral neck PIGSMO. Inclusion criteria were: non-displaced or mildly displaced PF/InF, and ImF (Mirels' score ≥8); life expectancy ≥1 month; unsuitability for surgical treatment due to sub-optimal clinical fitness, refusal of consent, or unacceptable delay to systemic therapy. RESULTS: Eleven patients were treated (mean age 63.7±13.5 years) due to ImF (63.6%, mean Mirels' score 10.1), PF (27.3%) or post-radiation InF (9.1%) under CT/fluoroscopy- (36.4%) or CBCT- (63.6%) guidance. Thirty-two screws were implanted and cement injection was added in 36.4% cases. Technical success was 90.9%. No procedure related complications were noted. At 1-month clinical follow-up (pain/walking impairment), 63.6% and 27.3% patients reported significant and mild improvement, respectively. Imaging follow-up (available in 63.6% cases) showed no signs of secondary fractures, neither of screws loosening at mean 2.8 months. Five patients (45.5%) died after PIGSMO (mean time interval 3.6 months). CONCLUSIONS: PIGSMO is technically feasible and safe in cancer patients with limited life expectancy; it offers good short-term results. Further prospective studies are required to corroborate mid- and to prove long-term efficacy of the technique.

Percutaneous Image-guided Laser Photocoagulation of Spinal Osteoid Osteoma: A Single-Institution Series.

PURPOSE: To retrospectively evaluate the safety and efficacy of percutaneous image-guided laser photocoagulation for the treatment of spinal osteoid osteoma (OO) in proximity to neural structures. MATERIALS AND METHODS: This study was institutional review board-approved with waivers of informed consent. From January 1994 until October 2014, 58 patients with spinal OO (mean age, 25 years; 40 men, 17 women) were treated in one institution by using laser photocoagulation with combined computed tomographic (CT) and fluoroscopic guidance. One patient was excluded because of less than 3 months of follow-up. All patients had typical clinical and imaging findings. Clinical features, radiologic data, and procedure-related data were reviewed, and limitations, complications, and failure rate were evaluated. All data were expressed as means ± standard deviation. P values of less than .05 were indicative of statistical significance. RESULTS: OO was in the vertebral body for 18 of 57 patients, the neural arch for 21 of 57 patients, and the articular process for 18 of 57 patients. Mean nidal diameter was 8 mm, and the mean distance from the closest neural structure was 6.6 mm (minimum distance, ≤5 mm in 35 of 57 patients). In 35 of 57 patients, no cortical coverage was present between the nidus and neural structure in danger. Mean total energy delivered was 1271 J (2-watt continuous power mode). Thermal insulation (carbon dioxide and/or hydrodissection), temperature monitoring, and electrostimulation were used in 42, 24, and one patient, respectively. Primary clinical success at 1 month was 98.2%. Total recurrence rate was 5.3%. All recurrences were addressed percutaneously. Secondary success rate was 100%. One-year follow-up is available in 54 of 57 patients. No major complications were noted. CONCLUSION: Spinal OO can be safely and effectively treated with percutaneous laser photocoagulation. In cases that are less than 8 mm to 10 mm distance and in the absence of cortical coverage, thermal protection techniques of the neural structures should be used.

The Metastatic Spine Disease Multidisciplinary Working Group Algorithms.

The Metastatic Spine Disease Multidisciplinary Working Group consists of medical and radiation oncologists, surgeons, and interventional radiologists from multiple comprehensive cancer centers who have developed evidence- and expert opinion-based algorithms for managing metastatic spine disease. The purpose of these algorithms is to facilitate interdisciplinary referrals by providing physicians with straightforward recommendations regarding the use of available treatment options, including emerging modalities such as stereotactic body radiation therapy and percutaneous tumor ablation. This consensus document details the evidence supporting the Working Group algorithms and includes illustrative cases to demonstrate how the algorithms may be applied.

Treatment of a spinal aneurysmal bone cyst using combined image-guided cryoablation and cementoplasty.

The authors describe the case of a 6.6-cm symptomatic spinal aneurysmal bone cyst (ABC) in a 17-year-old athlete treated percutaneously. Surgical treatment was not considered as the first option owing to its invasiveness and associated morbidity. CT-guided cryoablation of the expansile part of the ABC was performed for tumour shrinkage and nerve decompression. Thermal insulation, temperature monitoring and functional control/electrostimulation of the neural structures at risk were applied. Finally, the bony defect was cemented. No complications occurred during the procedure. Complete resolution of the ABC on imaging and clinical improvement were achieved. Percutaneous cryoablation should be considered as an alternative treatment option, especially when tumour size reduction is desired.

Interest of electrostimulation of peripheral motor nerves during percutaneous thermal ablation.

PURPOSE: We present our experience of utilizing peripheral nerve electrostimulation as a complementary monitoring technique during percutaneous thermal ablation procedures; and we highlight its utility and feasibility in the prevention of iatrogenic neurologic thermal injury. METHODS: Peripheral motor nerve electrostimulation was performed in 12 patients undergoing percutaneous image-guided thermal ablations of spinal/pelvic lesions in close proximity to the spinal cord and nerve roots. Electrostimulation was used in addition to existing insulation (active warming/cooling with hydrodissection, passive insulation with CO2 insufflation) and temperature monitoring (thermocouples) techniques. Impending neurologic deficit was defined as a visual reduction of muscle response or need for a stronger electric current to evoke muscle contraction, compared with baseline. RESULTS: Significant reduction of the muscle response to electrostimulation was observed in three patients during the ablation, necessitating temporary interruption, followed by injection of warm/cool saline. This resulted in complete recovery of the muscle response in two cases, while for the third patient the response did not improve and the procedure was terminated. No patient experienced postoperative motor deficit. CONCLUSION: Peripheral motor nerve electrostimulation is a simple, easily accessible technique allowing early detection of impending neurologic injury during percutaneous image-guided thermal ablation. It complements existing monitoring techniques and provides a functional assessment along the whole length of the nerve.

Percutaneous thermal ablation: how to protect the surrounding organs.

A variety of thermal ablation techniques have been advocated for percutaneous tumor management. Although the above techniques are considered safe, they can be complicated with unintended thermal injury to the surrounding structures, with disastrous results. In the present article we report a number of different insulation techniques (hydrodissection, gas dissection and balloon interposition, warming/cooling systems) that can be applied. Emphasis is given to the procedure-related details, and we present the advantages and drawbacks of the insulation techniques. We also provide tips on avoiding painful skin burns when treating superficial lesions. Finally, we point out the interest of temperature monitoring and how it can be achieved (use of thermocouples, fiberoptic thermosensors, or direct magnetic resonance imaging temperature mapping). The above thermal insulation and temperature monitoring techniques can be applied alone or in combination. Familiarity with these techniques is essential to avoid major complications and to increase the indications of thermal ablation procedures.