Percutaneous Transpedicular Fixation by PEEK Polymer Implants Combined with Cementoplasty for Vertebral Compression Fractures: A Pilot Study.

PURPOSE: To evaluate the feasibility and safety of percutaneous transpedicular fixation by PEEK polymer implants and cementoplasty for vertebral compression fracture (VCF). MATERIALS AND METHODS: From February 2019 to December 2019, 6 consecutive patients (3 men and 3 women; mean age 55 ± 8 years; range 40-64 years) who had percutaneous transpedicular fixation with cementoplasty for the treatment of VCF (5 tumor lesions, 1 traumatic) were included. The procedure duration, length of hospital stay, and complications were reported. Visual analog scale (VAS) and the Oswestry disability index (ODI) for pain and disability were assessed before and 2 months after the procedure. RESULTS: The mean procedure duration was 74 ± 47 min (range 20-140 min). The median length of hospital stay was 3 days (range 2-63) after the procedure. Only minor adverse events were reported (4 asymptomatic cement leakages) but no severe complications. No cases of procedural site fracture during follow-up were noted (median 198 days; range 78-238 days). The mean VAS score decreased from 6.2 ± 1.8 mm (median 6 mm; range 4-9 mm) before the procedure to 1.7 ± 2.1 mm (median 1; range 0-5 mm) after the procedure. The ODI decreased from 36 ± 14% (range 18-54%) before the procedure to 23 ± 10% (range 11-30%) at 2-months follow-up. CONCLUSIONS: Percutaneous transpedicular fixation of VCF by PEEK implants with cementoplasty appears feasible and safe.

Sedation and analgesia in interventional radiology: Where do we stand, where are we heading and why does it matter?

The aims of this review were to describe the rationale and the techniques of sedation in interventional radiology, and to compile the safety and efficacy results available so far in the literature. A systematic MEDLINE/PubMed literature search was performed. Preliminary results from several studies demonstrated the feasibility, the efficacy and the safety of using sedative techniques in interventional radiology. Beyond pharmacological sedation and clinical hypnosis, digital sedation could reduce the anxiety and pain associated with interventional radiology procedures.

Characterization of small (<4cm) solid renal masses by computed tomography and magnetic resonance imaging: Current evidence and further development.

Diagnosis of renal cell carcinomas (RCC) subtypes on computed tomography (CT) and magnetic resonance imaging (MRI) is clinically important. There is increased evidence that confident imaging diagnosis is now possible while standardization of the protocols is still required. Fat-poor angiomyolipoma show homogeneously increased unenhanced attenuation, homogeneously low signal on T2-weighted MRI and apparent diffusion coefficient (ADC) map, may contain microscopic fat and are classically avidly enhancing. Papillary RCC are also typically hyperattenuating and of low signal on T2-weighted MRI and ADC map; however, their gradual progressive enhancement after intravenous administration of contrast material is a differentiating feature. Clear cell RCC are avidly enhancing and may show intracellular lipid; however, these tumors are heterogeneous and are of characteristically increased signal on T2-weighted MRI. Oncocytomas and chromophobe tumors (collectively oncocytic neoplasms) show intermediate imaging findings on CT and MRI and are the most difficult subtype to characterize accurately; however, both show intermediately increased signal on T2-weighted with more gradual enhancement compared to clear cell RCC. Chromophobe tumors tend to be more homogeneous compared to oncocytomas, which can be heterogeneous, but other described features (e.g. scar, segmental enhancement inversion) overlap considerably between tumors. Tumor grade is another important consideration in small solid renal masses with emerging studies on both CT and MRI suggesting that high grade tumors may be separated from lower grade disease based upon imaging features.

Hepatic Arterial Embolization Using Cone Beam CT with Tumor Feeding Vessel Detection Software: Impact on Hepatocellular Carcinoma Response.

PURPOSE: Dedicated tumor feeding vessel detection software (TFVDS) using cone beam CT has shown a higher sensitivity to detect tumor feeding vessels during hepatic arterial embolization (HAE) of hepatocellular carcinoma (HCC) compared to 2D imaging. Our primary hypothesis was that HCC tumors treated with HAE guided by a TFVDS would show more complete response (CR) than when treated with 2D imaging alone. Secondary analysis of the impact on X-ray exposure was performed. MATERIALS AND METHODS: Nineteen males and 8 females (median age: 69 year, 46-85) with 44 tumors (median size: 38 mm, 6-100) treated with selective HAE between January 2013 and December 2014 were included. Exclusion criteria were: extra-hepatic supply, >4 tumors, tumor size >10 cm, and adjunctive local therapy. Baseline patient and procedure characteristics were reviewed. Differences in CR per modified Response Evaluation Criteria in Solid Tumors were assessed by univariate and multivariate analyses for tumor size, number, location, particles size, and use of TFVDS. RESULTS: Median imaging follow-up was 20.1 months (2-33). Use of TFVDS (13 patients, 19 tumors) was the only factor predictive of CR (OR = 3.85 [CI95%: 1.09, 13.67], p = 0.04) on univariate analysis but not on multivariate analysis (OR = 3.26 [0.87, 12.23], p = 0.08). A higher rate of CR was observed for HAE using TFVDS guidance versus 2D imaging alone (68.4%, 13-19, vs. 36%, 9-25, p = 0.03). Median dose area product was lower when TFVDS was used (149.7 Gy.cm2, 38-365, vs. 227.8 Gy.cm2, 85.3-468.6, p = 0.05). CONCLUSIONS: HCC embolized with TFVDS may result in improved local tumor response without increasing the dose exposure.

Irreversible electroporation and thermal ablation of tumors in the liver, lung, kidney and bone: What are the differences?

Focal treatment with radiofrequency, microwave and cryoablation has been increasingly used for the treatment of tumors in patients who cannot undergo surgical resection and in select patients with early stage or oligometastatic disease. Each of these ablation modalities has a unique working principle and biophysics underlying the ablative effect, which largely determines the clinical indication for its application. Irreversible electroporation, a relatively new ablation technique with a predominantly nonthermal cell killing mechanism has emerged as an alternative treatment technique for tumors that are contraindicated for thermal ablation because of safety or efficacy considerations. Here, established thermal ablation techniques are compared with irreversible electroporation for treatment of tumors in the lung, liver, kidney and bone, and rationale is provided to guide selection of the most appropriate technique for each clinical setting.

Contrast enhanced ultrasound imaging can predict vascular-targeted photodynamic therapy induced tumor necrosis in small animals.

AIMS: To evaluate the accuracy of contrast-enhanced ultrasound (CEUS) for monitoring tumor necrosis following WST-11 vascular targeted photodynamic therapy (VTP) using imaging-pathology correlation. METHODS: Renal adenocarcinoma cells were injected into the hindlimb of 13 BalB/c mice resulting in tumors ranging from 9.8 to 194.3mm3. US guidance was used to place a laser fiber into the tumor, and VTP was performed. CEUS was performed prior to animal sacrifice, 24h post-VTP. Whole tumors were extracted for histopathologic analysis using H&E and TUNEL staining. Pathology samples corresponding to the CEUS imaging plane were prepared in order to compare the size and extents of tumor necrosis. RESULTS: Tumor necrosis following VTP appeared as a central region of non-enhancement on CEUS, while viable tumor appeared as patchy regions of enhancement in the tumor periphery. The region of tumor necrosis measured in mean 66% and 64.8% of total tumor area on CEUS and pathology respectively (p=0.2). The size and location of the necrosis on CEUS images and pathology samples were found correlative with no inter-observer difference (weighted kappa of 0.771 and 0.823, respectively). CONCLUSION: CEUS allows accurate monitoring of VTP induced tumor necrosis in a small animal model.

Augmented osteoplasty for proximal femur consolidation in cancer patients: Biomechanical considerations and techniques.

According to the literature, prophylactic consolidation of lytic metastasis located in the proximal femur is recommended when the Mirels' score is above 8. Osteoplasty alone provides inadequate consolidation but various devices have been used in association for better consolidation. The aim of this review is to detail the augmented osteoplasty techniques published in the literature and to report their safeties and their efficacies to prevent pathological fracture of the proximal femur. A Pubmed research found 5 studies that evaluated augmented osteoplasty of the proximal femur in cancer patients. All devices demonstrate adequate safety and low rate of secondary pathological fractures.

Percutaneous image-guided biopsies of small renal tumors: Current practice and perspectives.

Percutaneous image-guided biopsies help better select patients with renal tumors smaller than 4cm. These biopsies are performed to reduce the risks of overtreatment and to discriminate between patients who need ablation therapy and those who require active surveillance. Percutaneous image-guided biopsies are effective for a definitive diagnosis with little risk of complications when cautions are observed. With the current addition of multiparametric imaging, standardized biopsy protocols may further help adapt therapeutic decisions. The aim of this review is to report the current indications and techniques of biopsy performed in case of small solid renal masses and to clarify the optimal conditions for the realization of these biopsies.

Percutaneous cryoablation of symptomatic venous malformations as a second-line therapeutic option: a five-year single institution experience.

PURPOSE: To report the mid-term outcomes of percutaneous cryoablation (PCA) performed as second-line therapeutic option of venous malformations (VM). MATERIAL AND METHODS: From 2011 to 2015, PCA was offered in 24 patients (mean age: 31 years, range: 12-64) as second-line treatment for recurrence of symptoms after sclerotherapy and when resection was not possible (due to lesion location or previous failure) or refused by the patient. Adverse effects were recorded, disease-free survival (DFS) and local tissue control (LTC) rates were calculated based on symptoms and volume evolution. RESULTS: Mean follow-up was 18.7 months (6-48). Nine (37.5%, 9/24) adverse effects occurred and three (12.5%, 3/24) were severe. Mean pain assessed by visual analog scale (VAS) was 41.7 mm (0-80) before treatment and 20.3 mm (0-80) (p=0.01) after. Mean volume decreased significantly after treatment from 22.4 cm3 (0.9-146) to 8.35 cm3 (0-81.3) (p<0.001). Pain recurred in nine patients and size of one lesion increased. The DFS and LTC rates were 54% [95%CI: 22.94-77.27] and 93.33% [61.26-99.03] at 24 months, respectively. Only VM volume >10 cm3 was associated with a higher risk of local recurrence (p=0.05). CONCLUSION: PCA as second-line treatment appears to be safe and effective for local control of VM according to mid-term results. KEY POINTS: • Percutaneous cryoablation of venous malformations appeared well tolerated. • Size of venous malformations decreased significantly after percutaneous cryoablation (p<0.001). • Pain decreased significantly after percutaneous cryoablation of venous malformations (p=0.01).

Percutaneous Image-Guided Cryoablation as Second-Line Therapy of Soft-Tissue Venous Vascular Malformations of Extremities: A Prospective Study of Safety and 6-Month Efficacy.

PURPOSE: To report the safety and short-term efficacy of percutaneous image-guided cryoablation performed as second-line therapy of venous vascular malformations (VVM) of extremities. MATERIALS AND METHODS: In this non-blinded, no-randomized trial, cryoablation was proposed in 14 patients presenting with symptomatic VVM for recurrences after treatment. Eligibility criteria were: cryoablation feasible, localization at least 5 mm from skin and nerves, absence of contra-indication for anesthesia. Safety was evaluated by the common terminology criteria for adverse events (AE). Clinical response was assessed by evaluating pain at day 7, month 2 and 6 using visual analog scale; quality of life before cryoablation and at 2 and 6 months after using questionnaire. Evolution of volume was evaluated by MRI at 6 months. Comparison was performed using the Wilcoxon test. RESULTS: A technical success was observed in all cases. While 11 patients (78.6%) presented AE (13 grade 1-2 and 3 grade 3), only two severe AE (grade 3) related to cryoablation occurred in two patients (14.3%) during the 6-month follow-up: one immediate sciatic paralysis and one delayed paresthesia. A clinical response was observed in 12 patients (85.7%) at 6 months. Pain decreased significantly from 42.5 ± 14.2 mm before the intervention to 11.8 ± 17.9 mm at 6 months (P = 0.002). A significant decrease in the mean volume from 12.8 ± 14.3 to 3 ± 2.7 cm3 was observed at 6 months (P = 0.002). CONCLUSION: Percutaneous cryoablation is a promising alternative treatment for sclerotherapy-resistant venous malformations. However, to improve safety, careful patient selection and treatment planning will be mandatory.

Precision of manual two-dimensional segmentations of lung and liver metastases and its impact on tumour response assessment using RECIST 1.1.

BACKGROUND: Response evaluation criteria in solid tumours (RECIST) has significant limitations in terms of variability and reproducibility, which may not be independent. The aim of the study was to evaluate the precision of manual bi-dimensional segmentation of lung, liver metastases, and to quantify the uncertainty in tumour response assessment. METHODS: A total of 520 segmentations of metastases from six livers and seven lungs were independently performed by ten physicians and ten scientists on CT images, reflecting the variability encountered in clinical practice. Operators manually contoured the tumours, firstly independently according to the RECIST and secondly on a preselected slice. Diameters and areas were extracted from the segmentations. Mean standard deviations were used to build regression models and 95% confidence intervals (95% CI) were calculated for each tumour size and for limits of progressive disease (PD) and partial response (PR) derived from RECIST 1.1. RESULTS: Thirteen aberrant segmentations (2.5%) were observed without significant differences between the physicians and scientists; only the mean area of liver tumours (p = 0.034) and mean diameter of lung tumours (p = 0.021) differed significantly. No difference was observed between the methods. Inter-observer agreement was excellent (intra-class correlation >0.90) for all variables. In liver, overlaps of the 95% CI with the 95% CI of limits of PD or PR were observed for diameters above 22.7 and 37.9 mm, respectively. An overlap of 95% CIs was systematically observed for area. No overlaps were observed in lung. CONCLUSIONS: Although the experience of readers might not affect the precision of segmentation in lung and liver, the results of manual segmentation performed for tumour response assessment remain uncertain for large liver metastases.