Comparative Study of Ablation Zone of EMPRINT HP Microwave Device with Contemporary 2.4 GHz Microwave Devices in an Ex Vivo Porcine Liver Model.

(1) Background: Percutaneous microwave ablation (MWA) is an accepted treatment of non-operative liver cancer. This study compares the ablation zones of four commercially available 2.45 GHz MWA systems (Emprint, Eco, Neuwave, and Solero) in an ex vivo porcine liver model. (2) Methods: Ex vivo porcine livers (n = 85) were obtained. Two ablation time setting protocols were evaluated, the manufacturer's recommended maximum time and a 3 min time, performed at the manufacturer-recommended maximum power setting. A total of 236 ablation samples were created with 32 (13.6%) samples rejected. A total of 204 samples were included in the statistical analysis. (3) Results: For single-probe protocols, Emprint achieved ablation zones with the largest SAD. Significant differences were found in all comparisons for the 3 min time setting and for all comparisons at the 10 min time setting except versus Neuwave LK15 and Eco. Emprint produced ablation zones that were also significantly more spherical (highest SI) than the single-probe ablations from all other manufacturers. No statistical differences were found for ablation shape or SAD between the single-probe protocols for Emprint and the three-probe protocols for Neuwave. (4) Conclusions: The new Emprint HP system achieved large and spherical ablation zones relative to other 2.45 GHz MWA systems.

Clinical utility of chest radiography for severe COVID-19.

BACKGROUND: Chest radiography (CXR) is performed more widely and readily than CT for the management of coronavirus disease (COVID-19), but there remains little data on its clinical utility. This study aims to assess the diagnostic performance of CXR, with emphasis on its predictive value, for severe COVID-19 disease. METHODS: A retrospective cohort study was conducted, 358 chest radiographs were performed on 109 COVID-19 patients (median age 44.4 years, 58 males and 30 with comorbidities) admitted between 22 January 2020 and 15 March 2020. Each CXR was reviewed and scored by three radiologists in consensus using a 72-point COVID-19 Radiographic Score (CRS). Disease severity was determined by the need for supplemental oxygen and mechanical ventilation. RESULTS: Patients who needed supplemental oxygen (n=19, 17.4%) were significantly older (P<0.001) and significantly more of them had co-morbidities (P=0.011). They also had higher C-reactive protein (CRP) (P<0.001), higher lactate dehydrogenase (LDH) (P<0.001), lower lymphocyte count (P<0.001) and lower hemoglobin (Hb) (P=0.001). Their initial (CRSinitial) and maximal CRS (CRSmax) were higher (P<0.001). Adjusting for age and baseline hemoglobin, the AUROC of CRSmax (0.983) was as high as CRPmax (0.987) and higher than the AUROC for lymphocyte countmin (0.897), and LDHmax (0.900). The AUROC for CRSinitial was slightly lower (0.930). CRSinitial ≥5 had a sensitivity of 63% and specificity of 92% in predicting the need for oxygen, and 73% sensitivity and 88% specificity in predicting the need for mechanical ventilation. CRS between the 6th and 10th day from the onset of symptoms (CRSD6-10) ≥5 had a sensitivity of 89% and specificity of 95% in predicting the need for oxygen, and 100% sensitivity and 86% specificity in predicting the need for mechanical ventilation. CONCLUSIONS: Adjusting for key confounders of age and baseline Hb, CRSmax performed comparable to or better than laboratory markers in the diagnosis of severe disease. CXR performed between the 6th and 10th days from symptom onset was a better predictor of severe disease than CXR performed earlier at presentation. A benign clinical course was seen in CXR that were normal or had very mild abnormalities.

The use of cone beam CT in achieving unipedicular spinal augmentation.

OBJECTIVE: To assess the feasibility of cone beam CT (CBCT) in achieving unipedicular access during spinal cement augmentation. METHODS: A retrospective review of all patients who underwent CBCT-guided unipedicular spinal augmentation procedures between 1 January 2012 and 15 June 2015 was performed. 59 patients (43 females 16 males; mean-age, 74.0 years; range, 52-90 years) underwent unipedicular spinal augmentation in 78 vertebral levels (T5-T9, n = 14; T10-L2, n = 42; L3-L5, n = 22). Degree of cross-over in contralateral hemivertebral body, complications and 30-day mortality were recorded. RESULTS: 97% (76/78) of procedures were technically successful. Two procedures failed owing to vertebral sclerosis. For vertebroplasty, all cases (6/6) demonstrated cross-over filling of cement and 50% (3/6) showed cement cross-over >50% of contralateral half of the vertebral body. For kyphoplasty, 13 out of 15 procedures demonstrated balloon and cement cross-over >50% of contralateral half of the vertebral body. Two kyphoplasty procedures required the second pedicle after midline cross-over of cement failed. Of the kyphoplasty procedures that were successfully performed with the unipedicular approach, 76.9% (10/13) showed cement cross-over >50% of contralateral half of the vertebral body. For stentoplasty, all cases (55/55) showed midline stent-cement complex cross-over and 78.2% (43/55) exhibited stent-cement complex cross-over >50% of contralateral half of the vertebral body. There was no major complication or mortality. Minor complications included asymptomatic cement extravasation (6.4%, n = 5) and self-limiting haematoma (1.3%, n = 1). CONCLUSION: Unipedicular access for spinal augmentation procedures is achieved at a high success rate with the use of CBCT. ADVANCES IN KNOWLEDGE: This article describes the novel use of CBCT to achieve unipedicular spinal augmentation. Unipedicular spinal augmentation has the potential to reduce risk, duration, radiation and cost while achieving similar results.

Arterial portography during transarterial chemoembolization: still a necessity in the age of contrast-enhanced cross-sectional imaging?

PURPOSE: To evaluate the necessity of arterial portography (AP) if a patent portal vein is seen on imaging before transarterial chemoembolization. MATERIALS AND METHODS: All patients who underwent transarterial chemoembolization between January 2004 and July 2011 were retrospectively recruited. The study included 131 patients (100 men, 31 women) undergoing 243 transarterial chemoembolization procedures. AP was performed during 93 procedures. The mean time interval between imaging performed before transarterial chemoembolization and the transarterial chemoembolization procedure was 46.5 days (range, 0-161 d). RESULTS: AP did not detect any new cases of portal vein thrombosis (PVT) when imaging performed transarterial chemoembolization showed a patent portal vein. Imaging performed after transarterial chemoembolization revealed one main PVT, one left PVT extending into the main portal vein, two left PVT, and one right PVT. When imaging performed before transarterial chemoembolization showed a patent portal vein and AP was omitted, imaging performed after transarterial chemoembolization showed one case of main PVT, two right PVT, and two left PVT. In both groups, there was no significant difference in mortality (P = .673) or morbidity (P = .581) related to transarterial chemoembolization. CONCLUSIONS: AP is unnecessary if transarterial chemoembolization is performed within a reasonable time frame following computed tomography or magnetic resonance imaging that showed a patent portal vein. Omitting AP potentially reduces contrast material and radiation burden to both the patient and the operator.