A Deeper Analysis of Volumetric Relightable Faces.

Portrait viewpoint and illumination editing is an important problem with several applications in VR/AR, movies, and photography. Comprehensive knowledge of geometry and illumination is critical for obtaining photorealistic results. Current methods are unable to explicitly model in 3D while handling both viewpoint and illumination editing from a single image. In this paper, we propose VoRF, a novel approach that can take even a single portrait image as input and relight human heads under novel illuminations that can be viewed from arbitrary viewpoints. VoRF represents a human head as a continuous volumetric field and learns a prior model of human heads using a coordinate-based MLP with individual latent spaces for identity and illumination. The prior model is learned in an auto-decoder manner over a diverse class of head shapes and appearances, allowing VoRF to generalize to novel test identities from a single input image. Additionally, VoRF has a reflectance MLP that uses the intermediate features of the prior model for rendering One-Light-at-A-Time (OLAT) images under novel views. We synthesize novel illuminations by combining these OLAT images with target environment maps. Qualitative and quantitative evaluations demonstrate the effectiveness of VoRF for relighting and novel view synthesis, even when applied to unseen subjects under uncontrolled illumination. This work is an extension of Rao et al. (VoRF: Volumetric Relightable Faces 2022). We provide extensive evaluation and ablative studies of our model and also provide an application, where any face can be relighted using textual input.

Percutaneous vertebroplasty of the cervical spine performed via a posterior trans-pedicular approach.

OBJECTIVES: Percutaneous vertebroplasty (PV) of the cervical spine has been traditionally performed with a trans-oral or antero-lateral approach. The posterior trans-pedicular approach (PTPA) has been sporadically reported. Therefore, the aim of this study is to retrospectively assess the technical feasibility, safety, and clinical outcomes of cervical PV performed with a PTPA. METHODS: All consecutive patients undergoing PV in cervical levels with PTPA (under general anesthesia and computed tomography [CT] guidance) from January 2008 to November 2019 were identified. The following data were collected: patients' demographics; indication for PV; vertebral level features; procedure-related variables; and clinical outcomes including complications and pain relief. RESULTS: Thirty-two patients (18 females, 14 males; mean age 61.1 ± 13.2 years, range 36-88) were included accounting for 36 vertebrae. Three vertebrae (3/36, 8%) were referred due to an underlying traumatic fracture, the remaining (33/36, 92%) due to a painful lytic tumor. Technical success was 97% (35/36 levels). Mean time required to deploy the trocar was 23 ± 11 min (range 7-60). Extra-vertebral asymptomatic cement leakage was observed in 3/35 (9%) vertebral levels. One patient (1/32, 3%) developed an acute cardiogenic pulmonary edema requiring admission in the intensive care unit; another patient (1/32, 3%) developed localized infection to the skin entry site, which was managed conservatively. At 1-month follow-up, the mean pain in the study population was 1.0 ± 1.1 (range 0-4/10) vs 6.2 ± 1.4 (range 4-9/10) at baseline (p < 0.05). CONCLUSIONS: Cervical PV performed via a CT-guided PTPA is technically feasible, safe, and results in effective pain relief. KEY POINTS: • Percutaneous vertebroplasty (PV) is a well-established technique for the treatment of benign and malignant compression fractures. • Common PV approaches used for cervical vertebrae include the trans-oral, antero-lateral, lateral, and sporadically the posterior trans-pedicular approach. • Retrospective analysis of our 11-year experience with the posterior trans-pedicular approach used for cervical vertebrae proved that such approach was safe and effective.

Large nearly spherical ablation zones are achieved with simultaneous multi-antenna microwave ablation applied to treat liver tumours.

AIM: To investigate the shape and the volume of ablation zones obtained with microwave ablation (MWA) performed with multiple antennas in liver tumours. MATERIALS AND METHODS: Tumour volume, number of antennas, size (long diameter (Dl), along the antenna axis; short diameter (Ds), perpendicular to the antenna axis; vertical diameter (Dv), vertical to both Dl and Ds) and shape (roundness index (RI); 1 corresponds to a sphere) of the ablation zone, ablation volume, and complications were evaluated. RESULTS: Mean Dl, Ds, and Dv were 4.7 ± 1.4 cm, 3.9 ± 1.4 cm, and 3.8 ± 1.0 cm, respectively. Mean RIs (Ds/Dl, Dv/Dl, and Dv/Ds) were 0.83 ± 0.13, 0.83 ± 0.17, and 1.02 ± 0.23, respectively, without any difference between the mean RI obtained with the double (0.84 ± 0.01) and that with the triple-antenna (0.93 ± 0.13) approach (p = 0.25). Mean ablation volume was 41 ± 32 cm3 (vs. mean tumour volume 13 ± 10 cm3; range 1-40; p < 0.001). No complications were noted. CONCLUSIONS: Simultaneous multi-antenna MWA of liver tumours results in large nearly spherical ablation zones. KEY POINTS: • Simultaneous multi-antenna microwave ablation of liver tumours results in nearly spherical ablation zones. • The multi-antenna approach generates oversized ablation volumes compared with the target tumour volume. • The multi-antenna approach is safe.

Complications of Percutaneous Bone Tumor Cryoablation: A 10-year Experience.

Background Percutaneous cryoablation has been shown to be effective in the management of painful bone tumors. However, knowledge of the complication rate and risk factors for complication is currently lacking. Purpose To report the complication rate and associated risk factors for bone tumor cryoablation. Materials and Methods This retrospective study reviewed complications in 239 consecutive patients (131 men and 108 women; median age, 64 years; age range, 6-86 years) who underwent cryoablation of 320 primary or metastatic bone tumors between January 2008 and November 2017. Common Terminology Criteria for Adverse Events was used to categorize complications as major (grade 3-4) or minor (grade 1-2). Multivariable analysis was performed for variables with P values less than .20, including age, tumor location, adjacent critical structures, number of cryoprobes, and Eastern Cooperative Oncology Group performance status (ECOG-PS). Results Among the 320 tumors, the total complication rate was 9.1% (29 of 320; 95% confidence interval [CI]: 6%, 12.2%). The major complication rate was 2.5% (eight of 320; 95% CI: 0.8%, 4.2%), with secondary fracture the most frequent complication (1.2% [four of 320]; mean delay, 71 days); cryoablation site infection, tumor seeding, bleeding, and severe hypotension were each observed in 0.3% (one of 320) of procedures. Minor complications included postprocedural pain (2.2% [seven of 320]), peripheral neuropathy (0.9% [three of 320]), and temporary paresthesia (0.9% [three of 320]). For all complications, associated risk factors included ECOG-PS greater than 2 (odds ratio [OR], 3.1 [95% CI: 3, 7.6]; P = .01), long-bone cryoablation (OR, 17.8 [95% CI: 2.3, 136.3]; P = .01), and use of more than three cryoprobes (OR, 2.5 [95% CI: 1.0, 6.0]; P = .04); for major complications, associated risk factors included age greater than 70 years (OR, 7.1 [95% CI: 1.6, 31.7]; P = .01) and use of more than three cryoprobes (OR, 23.6 [95% CI: 2.8, 199.0]; P = .01). Conclusion Bone tumor cryoablation is safe, with a 2.5% rate of major complications, most commonly secondary fracture (1.2%). Major complications are associated with age greater than 70 years and use of more than three cryoprobes. © RSNA, 2019 Online supplemental material is available for this article. See also the editorial by Jennings in this issue.

Percutaneous radiofrequency ablation of painful spinal metastasis: a systematic literature assessment of analgesia and safety.

PURPOSE: Radiofrequency ablation (RFA) is the most common percutaneous technique applied to treat painful spinal metastasis; however, experience in this field is somehow still limited. A systematic literature research was performed to understand the effects of RFA in terms of analgesia and safety. MATERIALS AND METHODS: Inclusion criteria for the studies were as follows: (1) randomised controlled or non-randomised studies with a prospective or retrospective design; (2) population made up of adults with spinal metastasis; (3) spinal metastasis treated with RFA alone or in combination/comparison with other treatments; (4) studies reporting about patients' pain before and at least one time-point following RFA; and (5) English-language studies. RESULTS: Seven hundred and thirty-three articles were screened and 8 (4 prospective, 4 retrospective) matched the inclusion criteria. Study population ranged between 10 and 92 patients across studies. Five out of eight studies reported a highly effective pain management (≥4 points of pain reduction between baseline and the last time-point available); 2/8 studies reported moderate results (≥2 points of pain reduction between baseline and the last time-point available). All studies combined RFA with cement augmentation in the vast majority of patients (40-100%) or metastasis (94-95.8%). Grade I-IIIa neural complications were reported in up to 16% of the cases and were always managed conservatively or with steroids. CONCLUSIONS: RFA, combined with vertebral augmentation in most of the cases, is effective and safe in achieving short- to mid-term (from 1 week to 6 months) analgesia in patients affected by painful spinal metastasis.

Low-power bipolar radiofrequency ablation and vertebral augmentation for the palliative treatment of spinal malignancies.

AIM: To investigate the analgesic properties and the safety of low power bipolar radiofrequency ablation (RFA) performed with internally cooled electrodes and vertebral augmentation for the treatment of painful spinal malignancies. MATERIALS AND METHODS: Consent was waived for retrospective study participation. Review of electronic records identified 11 consecutive patients (6 females; 5 males; mean age 61.3 ± 11.6 years) with one-index painful spinal tumour, who were treated between June 2016 and October 2017 with bipolar RFA and vertebral augmentation. Patients were treated if they presented with focal pain (≥4/10 on a 0-10 visual analogic scale in the 24-h period) corresponding to a metastatic vertebral level on cross sectional imaging. The Wilcoxon test was used to evaluate the significance of the post-operative pain. RESULTS: Lumbar levels were treated in 72.7% cases; metastatic epidural involvement was noted in 81.8% cases; 54.5% patients received associated treatments in addition to RFA, which was coupled to vertebral augmentation in all cases. Two (18.2%) complications were noted. Mean pain score measured at last clinical follow-up available (mean 1.9 ± 1.4 months) was 3.5 ± 2 (versus 7.8 ± 1.1 at baseline; p <0.01). CONCLUSIONS: Low-power bipolar RFA performed with internally cooled electrodes and coupled to vertebral augmentation provides safe and effective early analgesia in patients affected by painful spinal malignancies.

Percutaneous image-guided ablation of bone metastases: local tumor control in oligometastatic patients.

INTRODUCTION: Percutaneous image-guided cryo- (CA) and radiofrequency- (RFA) ablations have been widely used in the treatment of painful bone metastases (BM). However, paucity of data is available for the performance of these treatments when used with a curative intent. The aim of this study is to investigate the local progression free-survival (LPFS) after radical percutaneous image-guided ablation of BM in oligometastatic patients, and to identify predictive factors associated with local tumor progression. MATERIALS AND METHODS: This is a retrospective review of all patients who underwent percutaneous image-guided CA or RFA of BM with a radical intent between 2007 and 2018. RESULTS: Forty-six patients with a total of forty-nine BM underwent percutaneous image-guided CA (N = 37; 75,5%) or RFA (N = 12; 24,5%). Primary malignancies included thyroid (N = 11, 22.5%), breast (N = 21; 42.9%), lung (N = 8; 16.3%) and other (N = 9; 18,3%) cancers. Additional consolidation was performed after ablation in 20.4% cases (N = 10). Mean follow-up was 34.1 ± 22 months. Local progression at the treated site was observed in 28.5% cases (N = 14); 1- and 2-year LPFS was 76.8% and 71.7%, respectively. Size of BM (>2 cm) predicted local tumor progression (p = .002). CONCLUSIONS: Percutaneous image-guided locoregional therapies used in the radical treatment of BM in oligometastatic patients demonstrate significant rates of LPFS providing the size of BM ≤2 cm.

Evaluation of 70-150-µm doxorubicin-eluting beads for transcatheter arterial chemoembolization in the rabbit liver VX2 tumour model.

AIM: To evaluate the pharmacokinetic profile (PK) and embolization effect of 70-150-µm doxorubicin eluting beads (DEBs) following intra-arterial injection (i.a.) in the rabbit liver VX2 tumour model. MATERIALS AND METHODS: In this ACUC-approved study, 25 white New Zealand rabbits were randomly assigned into a small DEB group (SDB, n = 7, 70-150-µm DEBs), large DEB group (LDB, n = 7, 100-300-µm DEBs), untreated controls (n = 7), and doxorubicin controls (n = 4, without tumour, received i.a. 12.5 mg doxorubicin). Plasma PK was assessed up to 180 min post-injection. Drug tissue and liver enzyme levels, radiologic tumor response and histopathologic tumour necrosis were assessed at 7 days. RESULTS: Mean tumour doxorubicin concentrations were 922.83 nM (SD = 722.05) and 361.48 nM (SD = 473.23) for the SDB and LDB, respectively (p = 0.005). There was no statistically significant difference in tumour doxorubicinol, plasma doxorubicin and doxorubicinol PK values. More beads were observed in the SDB tumours (p = 0.01). Liver enzymes increased and gradually declined over the observation period, with significantly higher values in the SDB. CONCLUSION: In this preclinical study, plasma PK of i.a.-injected 70-150-µm DEBs was not different than that of 100-300-µm DEBs. More beads and higher tissue doxorubicin levels were observed in the SDB tumours. KEY POINTS: • Small and large doxorubicin-eluting beads show similar plasma pharmacokinetic profiles. • Higher tissue doxorubicin levels were observed in the small bead group. • Liver enzymes were overall significantly higher in the small bead group.

Intraprocedural C-arm dual-phase cone-beam CT: can it be used to predict short-term response to TACE with drug-eluting beads in patients with hepatocellular carcinoma?

PURPOSE: To investigate whether C-arm dual-phase cone-beam computed tomography (CT) performed during transcatheter arterial chemoembolization (TACE) with doxorubicin-eluting beads can help predict tumor response at 1-month follow-up in patients with hepatocellular carcinoma (HCC). MATERIALS AND METHODS: This prospective study was compliant with HIPAA and approved by the institutional review board and animal care and use committee. Analysis was performed retrospectively on 50 targeted HCC lesions in 29 patients (16 men, 13 women; mean age, 61.9 years ± 10.7) treated with TACE with drug-eluting beads. Magnetic resonance (MR) imaging was performed at baseline and 1 month after TACE. Dual-phase cone-beam CT was performed before and after TACE. Tumor enhancement at dual-phase cone-beam CT in early arterial and delayed venous phases was assessed retrospectively with blinding to MR findings. Tumor response at MR imaging was assessed according to European Association for the Study of the Liver (EASL) guidelines. Two patients were excluded from analysis because dual-phase cone-beam CT scans were not interpretable. Logistic regression models for correlated data were used to compare changes in tumor enhancement between modalities. The radiation dose with dual-phase cone-beam CT was measured in one pig. RESULTS: At 1-month MR imaging follow-up, complete and/or partial tumor response was seen in 74% and 76% of lesions in the arterial and venous phases, respectively. Paired t tests used to compare images obtained before and after TACE showed a significant reduction in tumor enhancement with both modalities (P < .0001). The decrease in tumor enhancement seen with dual-phase cone-beam CT after TACE showed a linear correlation with MR findings. Estimated correlation coefficients were excellent for first (R = 0.89) and second (R = 0.82) phases. A significant relationship between tumor enhancement at cone-beam CT after TACE and complete and/or partial tumor response at MR imaging was found for arterial (odds ratio, 0.95; 95% confidence interval [CI]: 0.91, 0.99; P = .023) and venous (odds ratio, 0.96; 95% CI: 0.93, 0.99; P = .035) phases with the multivariate logistic regression model. Radiation dose for two dual-phase cone-beam CT scans was 3.08 mSv. CONCLUSION: Intraprocedural C-arm dual-phase cone-beam CT can be used immediately after TACE with doxorubicin-eluting beads to predict HCC tumor response at 1-month MR imaging follow-up.

Image quality improvements in C-Arm CT (CACT) for liver oncology applications: preliminary study in rabbits.

INTRODUCTION: C-Arm CT (CACT) is a new imaging modality in liver oncology therapy that allows for the acquisition of 3D images intra-procedurally. CACT has been used to enhance intra-arterial therapies for the liver by improving lesion detection, avoiding non-target embolization, and allowing for more selective delivery of agents. However, one of the limitations of this technology is image artifacts created by respiratory motion. PURPOSE: To determine in this preliminary study improvements in image acquisition, motion compensation, and high resolution 3D reconstruction that can improve CACT image quality (IQ). MATERIAL AND METHODS: Three adult male New Zealand white rabbits were used for this study. First, a control rabbit was used to select the best x-ray acquisition imaging protocol and then two rabbits were implanted with liver tumor to further develop 3D image reconstruction and motion compensation algorithms. RESULTS: The best IQ was obtained using the low 80 kVp protocol with motion compensated reconstruction with high resolution and fast acquisition speed (60 fps, 5 s/scan, and 312 images). CONCLUSION: IQ improved by: (1) decreasing acquisition time, (2) applying motion-compensated reconstruction, and (3) high resolution 3D reconstruction. The findings of this study can be applied to future animal studies and eventually could be translated into the clinical environment.

Human hepatocellular carcinoma in a mouse model: assessment of tumor response to percutaneous ablation by using glyceraldehyde-3-phosphate dehydrogenase antagonists.

PURPOSE: To characterize tumor response to percutaneous injection of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) antagonists in a mouse model of human hepatocellular carcinoma (HCC). MATERIALS AND METHODS: Animal experiments were approved by the Johns Hopkins University Animal Care and Use Committee. Luciferase (luc) gene-expressing Hep3B tumor-bearing athymic nude mice were randomly divided into four groups of six mice each. Tumor-specific GAPDH inhibition was achieved by using percutaneous injection of GAPDH antagonists-3-bromopyruvate (3-BrPA) or GAPDH-specific short hairpin RNA (shRNA). Tumor response to treatment was assessed by using bioluminescence imaging and analysis of GAPDH function and apoptotic markers (caspase-3, caspase-9, and positive staining for terminal deoxynucleotidyl transferase-mediated deoxyuridine 5-triphospate nick end labeling). HCC samples from 34 patients were obtained from the Johns Hopkins tumor bank, as approved by the Institutional Review Board, for GAPDH expression analysis. Statistical analysis was performed by using a two-sample t test or Spearman rank correlation coefficient. RESULTS: In vitro, 3-BrPA affected Hep3B cell viability (half maximal inhibitory concentration = 0.15 mmol/L), and GAPDH shRNA suppressed (45.5%) colony formation. In vivo, percutaneous injection of GAPDH antagonists into luc-Hep3B tumors decreased bioluminescence imaging signal and viability (3-BrPA, P < .0001; GAPDH shRNA, P = .03). The 3-BrPA treatment primarily inhibited GAPDH activity (74.5%) compared with its expression (34.3%), whereas GAPDH shRNA inhibited both activity (60.6%) and expression (44.4%). Targeted inhibition of GAPDH by using 3-BrPA or shRNA induced apoptosis. HCC samples from patients demonstrated a strong correlation between GAPDH upregulation and the proto-oncogene c-jun expression (r = 0.543, P = .003). CONCLUSION: Percutaneous injection of GAPDH antagonists induces apoptosis and blocks Hep3B tumor progression, which demonstrates the therapeutic potential of targeting GAPDH in human HCC.

Quantitative and volumetric European Association for the Study of the Liver and Response Evaluation Criteria in Solid Tumors measurements: feasibility of a semiautomated software method to assess tumor response after transcatheter arterial chemoembolization.

PURPOSE: To show that hepatic tumor volume and enhancement pattern measurements can be obtained in a time-efficient and reproducible manner on a voxel-by-voxel basis to provide a true three-dimensional (3D) volumetric assessment. MATERIALS AND METHODS: Magnetic resonance (MR) imaging data obtained from 20 patients recruited for a single-institution prospective study were retrospectively evaluated. All patients had a diagnosis of hepatocellular carcinoma (HCC) and underwent drug-eluting beads (DEB) transcatheter arterial chemoembolization for the first time. All patients had undergone contrast-enhanced MR imaging before and after DEB transcatheter arterial chemoembolization; poor image quality excluded 3 patients, resulting in a final count of 17 patients. Volumetric RECIST (vRECIST) and quantitative EASL (qEASL) were measured, and segmentation and processing times were recorded. RESULTS: There were 34 scans analyzed. The time for semiautomatic segmentation was 65 seconds±33 (range, 40-200 seconds). vRECIST and qEASL of each tumor were computed<1 minute for each. CONCLUSIONS: Semiautomatic quantitative tumor enhancement (qEASL) and volume (vRECIST) assessment is feasible in a workflow-efficient time frame. Clinical correlation is necessary, but vRECIST and qEASL could become part of the assessment of intraarterial therapy for interventional radiologists.

Estrogen Receptor-Beta2 (ERß2)-Mutant p53-FOXM1 Axis: A Novel Driver of Proliferation, Chemoresistance, and Disease Progression in High Grade Serous Ovarian Cancer (HGSOC).

High grade serous ovarian cancer (HGSOC) is the most common and lethal subtype of epithelial ovarian cancer. Prevalence (~96%) of mutant p53 is a hallmark of HGSOC. Estrogen receptor-beta (ERß) has been reported to be another important player in HGSOC, although the pro-versus anti-tumorigenic role of its different isoforms remains unsettled. However, whether there is functional interaction between ERß and mutant p53 in HGSOC is unknown. ERß1 and ERß2 mRNA and protein analysis in HGSOC cell lines demonstrated that ERß2 is the predominant isoform in HGSOC. Specificity of ERß2 antibody was ascertained using cells depleted of ERß2 and ERß1 separately with isoform-specific siRNAs. ERß2-mutant p53 interaction in cell lines was confirmed by co-immunoprecipitation and in situ proximity ligation assay (PLA). Expression levels of ERß2, ERα, p53, and FOXM1 proteins and ERß2-mutant p53 interaction in patient tumors were determined by immunohistochemistry (IHC) and PLA, respectively. ERß2 levels correlate positively with FOXM1 levels and negatively with progression-free survival (PFS) and overall survival (OS). Quantitative chromatin immunoprecipitation (qChIP) and mRNA expression analysis revealed that ERß2 and mutant p53 co-dependently regulated FOXM1 gene transcription. The combination of ERß2-specific siRNA and PRIMA-1MET that converts mutant p53 to wild type conformation increased apoptosis. Our work provides the first evidence for a novel ERß2-mutant p53-FOXM1 axis that can be exploited for new therapeutic strategies against HGSOC.

A new versatile MR-guided high-intensity focused ultrasound (HIFU) device for the treatment of musculoskeletal tumors.

Magnetic Resonance (MR) Imaging-guided High Intensity focused Ultrasound (MRgHIFU) is a non-invasive, non-ionizing thermal ablation therapy that is particularly interesting for the palliative or curative treatment of musculoskeletal tumors. We introduce a new modular MRgHIFU device that allows the ultrasound transducer to be positioned precisely and interactively over the body part to be treated. A flexible, MR-compatible supporting structure allows free positioning of the transducer under MRI/optical fusion imaging guidance. The same structure can be rigidified using pneumatic depression, holding the transducer rigidly in place. Targeting accuracy was first evaluated in vitro. The average targeting error of the complete process was found to be equal to 5.4 ± 2.2 mm in terms of focus position, and 4.7° ± 2° in terms of transducer orientation. First-in-man feasibility is demonstrated on a patient suffering from important, uncontrolled pain from a bone metastasis located in the forearm. The 81 × 47 × 34 mm3 lesion was successfully treated using five successive positions of the transducer, under real-time monitoring by MR Thermometry. Significant pain palliation was observed 3 days after the intervention. The system described and characterized in this study is a particularly interesting modular, low-cost MRgHIFU device for musculoskeletal tumor therapy.

Role of FDG PET/CT and chest CT in the follow-up of lung lesions treated with radiofrequency ablation.

PURPOSE: To compare fluorine 18 fluorodeoxyglucose (FDG) positron emission tomography (PET) combined with computed tomography (PET/CT) and chest CT in the evaluation of the effectiveness of lung radiofrequency (RF) ablation. MATERIALS AND METHODS: Institutional review board approved the study, and all patients gave written informed consent. Thirty-four patients (22 men and 12 women; mean age, 64 years) planned to undergo lung RF ablation were prospectively included and underwent FDG PET/CT and chest CT before (pre-RF ablation PET) and 24 hours, 1 month, and 3 months after RF ablation. Persistent equivocal findings up to 3 months were followed up. RESULTS: Pre-RF ablation PET led to changes in the treatment strategy in nine patients (26%) by depicting unexpected metastases. Two patients without FDG uptake in lesions to be treated were excluded. Overall, 28 patients (46 lesions: five primary cancer, 41 metastases) were treated and followed up. Within 3 months after RF ablation, incomplete treatment was diagnosed in four of 28 patients (14%, three at 1 month and one at 3 months). Findings of FDG PET/CT were true-positive in four, false-positive in one, and true-negative in 23 patients. Findings of chest CT were true-positive in one, false-positive in one, false-negative in three, and true-negative in 23 patients. Inflammatory FDG uptake in mediastinal lymph nodes and at the needle path puncture site used for RF ablation was observed in 15%, 21%, and 15% of patients and in 19%, 11%, and 15% of patients at 24 hours, 1 month, and 3 months, respectively. CONCLUSION: FDG PET/CT can be used for the evaluation of the effectiveness of lung RF ablation. Inflammatory FDG uptake in mediastinal lymph nodes or at the needle path site used for RF ablation may occur.

Radiofrequency ablation of lung metastases close to large vessels during vascular occlusion: preliminary experience.

PURPOSE: To report an initial prospective evaluation of the technical feasibility, efficacy, and safety of combining percutaneous temporary balloon occlusion (PBO) of a large pulmonary artery adjacent to a metastatic lung tumor treated with percutaneous radiofrequency (RF) ablation. MATERIALS AND METHODS: In six patients, lung RF ablation with a multitined, expandable electrode with simultaneous PBO via femoral access was attempted with the use of digital angiography and multidetector computed tomography (CT). Follow-up imaging was obtained immediately after treatment, at 1-2 days, and at 2, 6, 9, and 12 months; positron emission tomography/CT was performed at 4 months. RESULTS: Metastases targeted measured 17-37 mm (22 ± 8) and were in contact with a pulmonary artery 3-5 mm. Temporary occlusion of the pulmonary arterial branch in contact with the tumor was technically possible in five of six patients. Postablation CT scans obtained within 2 days of the procedure showed ablation zones measuring 37-57 mm (47 ± 8) in their shortest diameter. Three patients developed lung infarction within 1 month after RF ablation, and two had to be readmitted. At 3 months after the procedure, four patients had persistent occlusion of the balloon-occluded vessel. No uptake was demonstrated 4 months after ablation; at 12 months, all tumors showed complete ablation on CT. CONCLUSIONS: RF ablation of lung tumors with PBO is a feasible technique, but it induces atelectasia and long-lasting vascular occlusion responsible for a high rate of readmission. The results of this small study warrant careful further exploration of the benefits of the technique, compared with RF ablation without PBO or other methods of ablative therapy.

Use of 3.0-Tesla high spatial resolution magnetic resonance imaging for diagnosis and treatment of cystic adventitial disease of the popliteal artery.

Cystic adventitial disease (CAD) of the popliteal artery is a rare vascular disease of unknown etiology in which a mucin-containing cyst develops in the adventitial layer of the artery. Early recognition and treatment of this condition will prevent progression of the popliteal thrombosis and critical ischemia. However, diagnosis of the condition is difficult. The combination of contrast-enhanced magnetic resonance (MR) angiography and the excellent soft-tissue resolution of MR imaging allow for detailed evaluation of patients with CAD and facilitate appropriate management decisions. We report the 3.0-Tesla MR imaging features of CAD in three patients and discuss the interest for this noninvasive imaging technique in such a setting.

A comparison of the results of arterial embolization for bleeding and non-bleeding gastroduodenal ulcers.

BACKGROUND: Although some authors have advocated the practice of arterial embolization for angiographically negative acute hemorrhage from gastroduodenal ulcers, this technique remains controversial. PURPOSE: To compare the results of arterial embolization for bleeding (BU) and non-bleeding (NBU) gastroduodenal ulcers. MATERIAL AND METHODS: Transcatheter embolization was performed in 57 patients (39 men, 18 women, mean age 69.8 years) who experienced acute bleeding from gastroduodenal ulcers. At the time of embolization active contrast extravasation was seen in 36 of 57 patients, while in the remaining 21 patients embolization was based on endoscopic findings. Patient demographics, clinical success, need for re-intervention secondary to re-bleeding, and 30-day complication and mortality rates were reviewed and compared between the two groups by using statistical analyses. RESULTS: In the BU group, the gastroduodenal artery (GDA) was embolized in 31 patients (86.1%), the left gastric artery (LGA) in three patients (8.3%), and the left gastroepiploic artery (LGEA) in two patients (5.6%). In the NBU group, the GDA was embolized in 18 patients (85.7%), and the LGA in three patients (14.3%). Clinical success (61.9 vs. 75.0%, P = 0.30), need for re-intervention (38.1 vs. 27.8%, P = 0.42), and 30-day complication (9.5 vs. 5.6%, P = 0.57), and mortality (28.6 vs. 25%, P = 0.77) rates were not statistically different between the two groups. Embolization in patients in NBU group did not have impact on clinical success (OR, 0.54; 95%CI, 0.17-1.72; P = 0.30). CONCLUSION: Arterial embolization in patients with angiographically NBU is as safe and effective as embolization in patients with BU.

Interventional Radiology Outpatient Clinics (IROC): Clinical Impact and Patient Satisfaction.

PURPOSE: To retrospectively analyze our interventional radiology outpatient clinics (IROC) for referral patterns, impact on interventional practice, and patient satisfaction. MATERIALS AND METHODS: Consultations performed between 2011 and 2019 were extracted. The two consecutive years with the highest number of consultations (n2018 = 1426; n2019 = 1595) were compared for unattended consultations (i.e., scheduled consultations with patients not showing-up); initial/follow-up consultations; hospital clinician/general practitioner referrals; initial consultations with radiologists not recommending interventions; procedural conversion rate (PCR; i.e., No. initial consultations resulting in interventions over the total number of initial consultations performed for the same clinical indication). A survey was conducted in 159 patients to determine their satisfaction. RESULTS: Consultations increased from 2011 to 2019 by 130%. In 2018-2019, the number of unattended consultations was stable (7.0% vs 6.6%; P = .68). The referrals were for back pain (42.2%), interventional oncology (40.5%), and arteriovenous malformations (9.0%). For back pain, in 2019, there were fewer consultations with radiologists not recommending interventions and increased PCR compared to 2018 (11.9% vs. 17.7%; 88.1% vs. 82.3%; respectively; P = .01). For interventional oncology, follow-up consultations and general practitioner referrals increased in 2019 compared to 2018 (43.0% vs 35.3%; P = .01; 24.4% vs. 12.7%; P < .01; respectively). No other changes were noted. Cumulative 2018-2019 PCR was ≥ 85.4%. 99.2% responders highly appreciated their IROC experience. Quality of secretarial and medical services were the main aspects evaluated to rate the experience with IROC. CONCLUSION: IROC results in high PCR. Recent changes in referral/impact on IR practice were noted with patients referred for back pain and interventional oncology. LEVEL OF EVIDENCE IV: Level 4, Case Series.