Intradiscal Gelified Ethanol Nucleolysis versus Endoscopic Surgery for Lumbar Disc Herniation Radiculopathy

The purpose of this study was to retrospectively compare efficacy and safety between intradiscal injection of a gelified ethanol product and tubular discectomy in the treatment of intervertebral disk herniation. A bi-central institutional database research identified forty (40) patients suffering from symptomatic contained disc herniation. Nucleolysis Group included 20 patients [mean 50.05 ± 9.27 years-of-age (male/female 14/6-70/30%)] and Surgery Group included 20 patients [mean 48.45 ± 14.53 years-of-age, (male/female 12/8-60/40%)]. Primary outcome was overall 12-month improvement over baseline in leg pain (NVS units). Procedural technical outcomes were recorded, and adverse events were evaluated at all follow-up intervals. CIRSE classification system was used for complications' reporting. Mean pre-operative pain score in Nucleolysis Group was 7.95 ± 0.94 reduced to 1.25 ± 1.11 at month 1 and 0.45 ± 0.75 NVS units at year 1. Mean pre-operative pain score in Surgery Group was 7.65 ± 1.13 reduced to 1.55 ± 1.79 at month 1 and 0.70 ± 1.38 NVS units at year 1. Pain decrease was statistically significant after both procedures (p < 0.001). There was no statistically significant difference between pain reduction in both groups (p = 0.347). The decrease differences of the pain effect upon general activities, sleeping, socializing, walking, and enjoying life in the follow-up period between the two groups were not statistically significant. No complications were noted in both groups. Results from the current study report that intradiscal injection of a gelified ethanol and tubular discectomy were equally effective on terms of efficacy and safety for the treatment of symptomatic lumbar intervertebral disc herniation regarding the 12-month mean leg pain improvement. Both achieved similar rapid significant clinical improvement persisting throughout follow-up period.

Role of Percutaneous Ablation in the Management of Intrahepatic Cholangiocarcinoma

Cholangiocarcinoma (CCA) is an invasive cancer accounting for <1% of all cancers and 10-15% of primary liver cancers. Intrahepatic CCA (iCCA) is associated with poor survival rates and high post-surgical recurrence rates whilst most diagnosed patients are not surgical candidates. There is a growing literature suggesting percutaneous ablative techniques for the management of patients with iCCA measuring ≤3 cm with contraindications to surgery as well as for recurrent or residual tumors aiming to provide local cancer treatment and control. Most used ablative therapies for iCCA include radiofrequency and microwave ablation with irreversible electroporation, cryoablation and reversible electroporation (electrochemotherapy) being less commonly encountered techniques. Due to the infiltrative margins of the lesion, there is a need for larger safety margins and ablation zone; multi-apparatus ablation or other variations of the technique such as balloon-assisted approaches can be utilized aiming to increase size of the zone of necrosis. The present review paper focuses upon the current role of percutaneous ablative techniques for the therapeutic management of iCCA. The purpose of this review is to present the current minimally invasive ablative techniques in the treatment of iCCA, including local control and survival rates.

Emerging Indications for Interventional Oncology: Expert Discussion on New Locoregional Treatments

Interventional oncology (IO) employs image-guided techniques to perform minimally invasive procedures, providing lower-risk alternatives to many traditional medical and surgical therapies for cancer patients. Since its advent, due to rapidly evolving research development, its role has expanded to encompass the diagnosis and treatment of diseases across multiple body systems. In detail, interventional oncology is expanding its role across a wide spectrum of disease sites, offering a potential cure, control, or palliative care for many types of cancer patients. Due to its widespread use, a comprehensive review of the new indications for locoregional procedures is mandatory. This article summarizes the expert discussion and report from the "MIOLive Meet SIO" (Society of Interventional Oncology) session during the last MIOLive 2022 (Mediterranean Interventional Oncology Live) congress held in Rome, Italy, integrating evidence-reported literature and experience-based perceptions. The aim of this paper is to provide an updated review of the new techniques and devices available for innovative indications not only to residents and fellows but also to colleagues approaching locoregional treatments.

Vertebral Augmentation: Is It Time to Get Past the Pain? A Consensus Statement from the Sardinia Spine and Stroke Congress

Vertebral augmentation has been used to treat painful vertebral compression fractures and metastatic lesions in millions of patients around the world. An international group of subject matter experts have considered the evidence, including but not limited to mortality. These considerations led them to ask whether it is appropriate to allow the subjective measure of pain to so dominate the clinical decision of whether to proceed with augmentation. The discussions that ensued are related below.

Navigation Guidance for Percutaneous Splanchnic Nerve Radiofrequency Neurolysis: Preliminary Results

Background and Objectives: To describe preliminary results upon the application of the “Cube Navigation System” (CNS) for computed tomography (CT)-guided splanchnic nerve radiofrequency neurolysis. Materials and Methods: CT-guided splanchnic nerve neurolysis was performed in five patients; in all cases, neurolysis was performed under CT guidance using the CNS. The mean patient age was 71.6 years (range 54–81 years; male/female: 5/0). Technical success, parameters of the neurolysis session and complications were evaluated. Technical success was defined as a needle position on the defined target. Session parameters included procedure time and number of scans. The CIRSE reporting system was used for complications’ classification and grading. Results: Technical success was obtained in all cases; in 1/5 patients, a slight correction in needle orientation was necessary. Mean procedure time was 12.4 min (range 8–19 min); an average of four CT scans was recorded in the five neurolysis sessions. There were no complications or material failures reported in the present study. Conclusions: Preliminary results of the present study show that computed tomography (CT)-guided splanchnic nerve radiofrequency neurolysis using the CNS is an accurate and time-efficient percutaneous procedure. More prospective and comparative studies with larger patient samples are necessary for verification of this system as well as for drawing broader conclusions.

Update on Interventional Radiology of the Spine

Interventional radiologists now perform spinal interventions routinely for diagnostic and therapeutic purposes. New technologies for the management of spine pathologies have emerged with promising results in terms of safety and efficacy. Interventional radiology techniques in the spine include percutaneous biopsy and therapies for intervertebral disk herniation or spinal stenosis, facet and sacroiliac joint pathologies, vertebral and sacral fractures, and metastases. These techniques can also be easily combined one with the other or to further therapeutic approaches including systemic therapies, surgical approaches, and radiotherapy. This review provides a comprehensive overview of current percutaneous imaging-guided interventional radiology techniques in the spine. It will help readers become familiar with the most common indications, learn about different technical considerations during performance, and review the available evidence. Controversies concerning new products and technical approaches are also addressed.

Percutaneous Ablation of Metastatic Lymph Nodes: An Insight from the Comparison of Efficacy and Safety Between Cryoablation and Radiofrequency Ablation

PURPOSE

To retrospectively compare efficacy and safety of computed tomography (CT)-guided percutaneous ablation of metastatic lymph nodes (LN) between cryoablation (CA) and radiofrequency ablation (RFA).

MATERIALS AND METHODS

A bi-central institutional database research identified 28 patients (42 metastatic LNs) who underwent percutaneous CT-guided ablation. RFA group included 18 patients/26 tumors; CA group included 10 patients/16 tumors. Contrast-enhanced CT or MRI was used for post-ablation follow-up. Patient and tumor characteristics, technical and clinical success on a per tumor and a per patient basis and complication rates were recorded, evaluated and compared between the 2 groups.

RESULTS

Both RFA and CA groups had the same median tumor size (2.00 vs. 2.20 cm, p = 0.257), the same median follow-up time (20.50 vs. 20.00 months, p = 0.923) and the same median length of hospital stay (1.00 vs. 1.00 days, p = 0.283). CA group had a higher median procedure time (110.50 vs. 52.00 min, p = 0.001). On a per lesion basis, the overall complete response post-ablation was 88.46% (23/26 lesions) in the RFA and 93.75% (15/16 lesions) in the CA group; no association was revealed between local tumor control and ablation technique (p = 0.709). No complications were recorded in both Groups. On a per patient basis, CA had a longer disease-free interval (24.00 vs. 14.50, p = 0.012) which, however, did not affect the overall survival between the two techniques (26.0 vs. 22.0, p = 0.099 for CA and RFA respectively).

CONCLUSION

Our limited data suggest that CT-guided RFA and CA are equally effective on terms of efficacy and safety for the treatment of metastatic lymph nodes.

Intradiscal oxygen-ozone chemonucleolysis versus microdiscectomy for lumbar disc herniation radiculopathy: a non-inferiority randomized control trial

BACKGROUND CONTEXT

Low back pain with or without radicular leg pain is an extremely common health condition significantly impacting patient's activities and quality of life. When conservative management fails, epidural injections providing only temporary relief, are frequently utilized. Intradiscal oxygen-ozone may offer an alternative to epidural injections and further reduce the need for microdiscectomy.

PURPOSE

To compare the non-inferiority treatment status and clinical outcomes of intradiscal oxygen-ozone with microdiscectomy in patients with refractory radicular leg pain due to single-level contained lumbar disc herniations.

STUDY DESIGN / SETTING

Multicenter pilot prospective non-inferiority blocked randomized control trial conducted in three European hospital spine centers.

PATIENT SAMPLE

Forty-nine patients (mean 40 years of age, 17 females/32 males) with a single-level contained lumbar disc herniation, radicular leg pain for more than six weeks, and resistant to medical management were randomized, 25 to intradiscal oxygen-ozone and 24 to microdiscectomy. 88% (43 of 49) received their assigned treatment and constituted the AS-Treated (AT) population.

OUTCOME MEASURES

Primary outcome was overall 6-month improvement over baseline in leg pain. Other validated clinical outcomes, including back numerical rating pain scores (NRS), Roland Morris Disability Index (RMDI) and EQ-5D, were collected at baseline, 1 week, 1-, 3-, and 6-months. Procedural technical outcomes were recorded and adverse events were evaluated at all follow-up intervals.

METHODS

Oxygen-ozone treatment performed as outpatient day surgeries, included a one-time intradiscal injection delivered at a concentration of 35±3 μg/cc of oxygen-ozone by a calibrated delivery system. Discectomies performed as open microdiscectomy inpatient surgeries, were without spinal instrumentation, and not as subtotal microdiscectomies. Primary analyses with a non-inferiority margin of -1.94-point difference in 6-month cumulative weighted mean leg pain NRS scores were conducted using As-Treated (AT) and Intent-to-Treat (ITT) populations. In post hoc analyses, differences between treatment groups in improvement over baseline were compared at each follow-up visit, using baseline leg pain as a covariate.

RESULTS

In the primary analysis, the overall 6-month difference between treatment groups in leg pain improvement using the AT population was -0.31 (SE, 0.84) points in favor of microdiscectomy and using the ITT population, the difference was 0.32 (SE, 0.88) points in favor of oxygen-ozone. The difference between oxygen-ozone and microdiscectomy did not exceed the non-inferiority 95% confidence lower limit of treatment difference in either the AT (95% lower limit, -1.72) or ITT (95% lower limit, -1.13) populations. Both treatments resulted in rapid and statistically significant improvements over baseline in leg pain, back pain, RMDI, and EQ-5D that persisted in follow-up. Between group differences were not significant for any outcomes. During 6-month follow-up, 71% (17 of 24) of patients receiving oxygen-ozone, avoided microdiscectomy. The mean procedure time for oxygen-ozone was significantly faster than microdiscectomy by 58 minutes (p<.0010) and the mean discharge time from procedure was significantly shorter for the oxygen-ozone procedure (4.3±2.9 hours vs. 44.2±29.9 hours, p<.001). No major adverse events occurred in either treatment group.

CONCLUSIONS

Intradiscal oxygen-ozone chemonucleolysis for single-level lumbar disc herniations unresponsive to medical management, met the non-inferiority criteria to microdiscectomy on 6-month mean leg pain improvement. Both treatment groups achieved similar rapid significant clinical improvements that persisted and overall, 71% undergoing intradiscal oxygen-ozone were able to avoid surgery.

Computed tomography guided radiofrequency ablation of osteoid osteoma in children: a single center's experience

OBJECTIVE

To report a single center's experience evaluating the efficacy and safety of computed tomography-guided radiofrequency ablation for the treatment of osteoid osteoma in children.

MATERIALS AND METHODS

Institutional database research identified 33 symptomatic patients (≤ 18 years of age; male/female ratio: 21/12, mean age 13.09 ± 3.66) with osteoid osteoma who were treated by CT-guided RFA. Technical and clinical success as well as complication rates were recorded. The duration of the procedure, the number of computed tomography scans and the results of the biopsy were assessed. Pain, prior, the following morning and 1 week, 1/6/12 months after the procedure were compared by means of a numeric visual scale (NVS) questionnaire.

RESULTS

Mean lesion size was 8.28 ± 4.24 mm. Mean follow-up was 23.33 ± 17.61 months (range 12-62). Mean pain score prior to radiofrequency ablation was 9.06 ± 0.80 NVS units. On week 1 and 1/6/12 months, all patients were pain-free reporting 0 NVS units (p < 0.05). The mean procedure time was 54 min (range 51-59) and a mean of 7 CT scans were performed during the ablation session. RF electrode was successfully placed in the center of the nidus in all cases. In our study, none of our patient experienced recurrence of the pain, nor complications.

CONCLUSION

The present study demonstrates that percutaneous CT-guided radiofrequency ablation constitutes a safe and effective technique for osteoid osteoma treatment in children.

Consensus Guidelines for the Definition of Time-to-Event End Points in Image-guided Tumor Ablation: Results of the SIO and DATECAN Initiative

There is currently no consensus regarding preferred clinical outcome measures following image-guided tumor ablation or clear definitions of oncologic end points. This consensus document proposes standardized definitions for a broad range of oncologic outcome measures with recommendations on how to uniformly document, analyze, and report outcomes. The initiative was coordinated by the Society of Interventional Oncology in collaboration with the Definition for the Assessment of Time-to-Event End Points in Cancer Trials, or DATECAN, group. According to predefined criteria, based on experience with clinical trials, an international panel of 62 experts convened. Recommendations were developed using the validated three-step modified Delphi consensus method. Consensus was reached on when to assess outcomes per patient, per session, or per tumor; on starting and ending time and survival time definitions; and on time-to-event end points. Although no consensus was reached on the preferred classification system to report complications, quality of life, and health economics issues, the panel did agree on using the most recent version of a validated patient-reported outcome questionnaire. This article provides a framework of key opinion leader recommendations with the intent to facilitate a clear interpretation of results and standardize worldwide communication. Widespread adoption will improve reproducibility, allow for accurate comparisons, and avoid misinterpretations in the field of interventional oncology research. Published under a CC BY 4.0 license. Online supplemental material is available for this article. See also the editorial by Liddell in this issue.

Percutaneous computed tomography-guided radiofrequency ablation of a spinal osteoid osteoma abutting the dura: a case report and review of the literature

PURPOSE

Osteoid osteomas in the spine constitute a challenging group for both surgical and percutaneous approaches. Purpose of the present study is to report a case report of a spinal osteoid osteoma in a challenging spinal location and review literature for safety and efficacy of the technique.

METHODS

We report a case of spinal osteoid osteoma extending in the epidural space and abutting the dura in a pediatric patient treated by percutaneous computed tomography-guided radiofrequency ablation. This is not a systematic review of the literature. A number of separate literature searches were performed. Non-English studies and case reports were excluded from the study. All references of the obtained articles were also evaluated for any additional information.

RESULTS

Although all prophylactic measures were taken (hydrodissection, thermocouples and neurophysiologic monitoring) and the procedure was uneventful, patient within three hours, was unable to raise or bend the unilateral lower extremity below the knee. Pain reduction was significant from the first morning post-ablation and during the follow-up period of 18 months. MR scan was within normal limits. Dexamethasone was iv injected for 24 h and prescribed per os for 7 days. At follow-up 1 week later mobility of the lower extremity had returned to normal.

CONCLUSION

As far as spine ablation is concerned, all prophylactic measures should be taken; neurophysiologic monitoring seems to be more sensitive than temperature measurement. Intravenous and per os corticosteroids are extremely useful in case of nerve damage.

Percutaneous Navigation under Local Anesthesia for Computed Tomography-Guided Microwave Ablation of Malignant Liver Lesions Located in the Hepatic Dome

Background and Objectives: The aim of the present study was to report the safety and efficacy of percutaneous navigation under local anesthesia for computed tomography-guided microwave ablation of malignant liver lesions located in the hepatic dome. Patients with primary and secondary malignant liver lesions located in the hepatic dome who underwent percutaneous computed tomography-guided microwave ablation using a computer-assisted navigation system under local anesthesia were prospectively evaluated. The primary objective was technical success. Materials and Methods: The sample consisted of 10 participants (16 lesions) with a mean age of 60.60 years (SD = 9.25 years) and a mean size of 20.37 ± 7.29 cm, and the mean follow-up time was 3.4 months (SD = 1.41) months. Results: Primary technical success was 93.75%. Tumor remnant was noticed at one month follow-up in a single metastatic lesion, which was re-treated with an ablation session, and no tumor remnant was depicted in the subsequent imaging follow-up (secondary technical success 100%). Grade I self-limited complications (according to the CIRSE classification system) included small pleural effusion (n = 1) and minor bleeding post antenna removal (n = 1) requiring nothing but observation. Conclusions: the findings of the present study indicate that percutaneous navigation under local anesthesia is a safe and efficacious approach for computed tomography-guided microwave ablation of malignant liver lesions located in the hepatic dome. Large randomized controlled studies are warranted to observe treatment effectiveness and compare the results with those of other options.

Computed Tomography-Guided Percutaneous Microwave Ablation for Renal Cell Carcinoma: Impact of Tumor Size on the Progression Survival Rates

The aim of the present study was to evaluate the safety and efficacy of computed tomography (CT)-guided percutaneous microwave ablation (MWA) of renal cell carcinoma (RCC) along with identifying prognostic factors affecting the progression survival rate. Institutional database retrospective research identified 69 patients with a biopsy proven solitary T1a (82.6%) or TIb (17.4%) RCC who have underwent percutaneous CT-guided MWA. Kaplan–Meier survival estimates for events were graphed and Cox regression analysis was conducted. Mean patient age was 70.4 ± 11.5 years. Mean size of the lesions was 3 ± 1.3 cm. Mean follow up time was 35.6 months (SD = 21.1). The mean progression free survival time from last ablation was 84.2 months. For T1a tumors, the cumulative progression free survival rate for 1, 6, 12 and 36 months were 100% (SE = 0%), 91.2% (SE = 3.7%), 91.2% (SE = 3.7%) and 87.5% (SE = 4.4%); the recurrence free survival rate for T1a RCC was 94.9%. For T1b tumors, the cumulative progression free survival rate for 1, 6, 12 and 36 months were 100% (SE = 0%), 63.6% (SE = 14.5%), 63.6% (SE = 14.5%) and 63.6% (SE = 14.5%). Grade 1 complications were recorded in 5 (7.2%) patients. Significantly greater hazard for progression was found in cases with a tumor size > 4 cm (HR = 9.09, p = 0.048). No statistically important difference regarding tumor progression was recorded between T1a tumors with a diameter ≤3 cm and >3 cm. In summary, the results of the present study show that CT guided percutaneous MWA is an effective technique for treatment of T1a renal cell carcinomas, irrespective of tumor size. T1b tumors were associated with higher progression rates.

A Bicentric Propensity Score Matched Study Comparing Percutaneous Computed Tomography-Guided Radiofrequency Ablation to Magnetic Resonance-Guided Focused Ultrasound for the Treatment of Osteoid Osteoma

PURPOSE

To assess the safety and efficacy of computed tomography-guided radiofrequency (RF) ablation and magnetic resonance-guided focused ultrasound (MRgFUS) in the treatment of osteoid osteoma with a long-term follow-up study.

MATERIALS AND METHODS

Database research was performed at 2 different centers with experience in musculoskeletal interventions. Both centers, one performing RF ablation and the other MRgFUS, identified 116 patients who underwent either RF ablation or MRgFUS procedures for the treatment of symptomatic osteoid osteoma and retrospectively evaluated data regarding pain scores using a visual analog scale (VAS). Complications were recorded according to the Cardiovascular and Interventional Radiological Society of Europe classification system. Propensity score matching for multiple variables was performed. Pain scores before and after therapy were compared.

RESULTS

Of 116 patients treated, 61 and 55 underwent RF ablation and MRgFUS, respectively. Before treatment, the mean reported pain in the 2 groups were 9.1 ± 0.88 (RF ablation) and 8.7 ± 0.73 (MRgFUS) VAS units. After treatment, a statistically significant (P < .00001) overall reduction in pain symptomatology was recorded. No statistically significant difference was observed between the mean values of pain after treatment in both groups (P = .256). Over a mean of >2 years of follow-up, 4 cases of relapse (RF ablation, 1; MRgFUS, 3) and 1 complication (RF ablation) were observed. The analysis from propensity score matching that identified a matched cohort of 48 patients showed similar results.

CONCLUSIONS

The 2 techniques for the treatment of osteoid osteoma resulted in profound and similar pain relief. The presence of thick cortical bone over the nidus can reduce the effectiveness of MRgFUS.

Musculoskeletal Oncologic Interventions: Proceedings from the Society of Interventional Radiology and Society of Interventional Oncology Research Consensus Panel

Musculoskeletal interventions are increasingly used with palliative and curative intent in the multidisciplinary treatment of oncology patients with bone and soft-tissue tumors. There is an unmet need for high-quality evidence to guide broader application and adoption of minimally invasive interventional technologies to treat these patients. Therefore, the Society of Interventional Radiology Foundation and the Society of Interventional Oncology collaborated to convene a research consensus panel to prioritize a research agenda addressing the gaps in the current evidence. This article summarizes the panel's proceedings and recommendations for future basic science and clinical investigation to chart the course for interventional oncology within the musculoskeletal system. Key questions that emerged addressed the effectiveness of ablation within specific patient populations, the effect of combination of ablation with radiotherapy and/or immunotherapy, and the potential of standardization of techniques, including modeling and monitoring, to improve the consistency and predictability of treatment outcomes.

A Technical Report on the Performance of Percutaneous Cryoneurolysis of Splanchnic Nerves for the Treatment of Refractory Abdominal Pain in Patients with Pancreatic Cancer: Initial Experience

PURPOSE

To report our preliminary results upon feasibility, efficacy and safety of percutaneous splanchnic nerves cryoneurolysis for the treatment of abdominal pain refractory to conservative medication in patients with pancreatic cancer MATERIALS METHODS: Institutional database research (retrospective review of prospectively collected data from April 2019 till August 2020) identified 5 patients with pancreatic cancer and pain refractory to conservative medication who underwent percutaneous cryoneurolysis of splanchnic nerves. In all patients, percutaneous cryoneurolysis was performed with posterolateral paravertebral approach using a 17 Gauge cryoprobe under computed tomography guidance and local anesthesia. Self-reported pain scores were assessed before and at the last follow-up using a pain inventory with visual analog scale (VAS) units.

RESULTS

Mean patient age was 63.81 years (male-female: 3-2). Mean pain score prior to cryoanalgesia of splanchnic nerves was 9.4 VAS units. This score was reduced to a mean value of 2.6, 2.6 and 3 VAS units at 1, 3 and 6 months of follow-up, respectively. All patients reported significantly reduced analgesic usage. No complication was reported according to the CIRSE classification system. The mean procedure time was 44.4 min (range 39-50 min), including local anesthesia, cryoprobe(s) placement, ablation and post-procedural CT evaluation.

CONCLUSION

Percutaneous cryoanalgesia of the splanchnic nerves is a minimally invasive, safe and effective procedure for pancreatic cancer pain relief. A larger, randomized trial is justified to substantiate these findings.

Percutaneous Microwave Ablation of Liver Lesions: Differences on the Sphericity Index of the Ablation Zone between Cirrhotic and Healthy Liver Parenchyma

To compare different parameters of the sphericity index of the ablation zone following microwave ablation (MWA) on cirrhotic- and healthy-liver parenchyma in a series of patients treated with the same MWA system. Institutional database research identified 46 patients (77 lesions) who underwent MWA. “Cirrhotic liver group” (CLG) included 35 hepatocellular carcinoma lesions; “healthy liver group” (HLG) included 42 metastatic lesions. The long axis (LAD), short axis 1 (SAD-1) and 2 (SAD-2), the mean SAD-1 and SAD-2 (mSAD) diameter (in mm) and the mean sphericity (mSPH) index of the ablation zones were evaluated for each treated lesion in both groups from baseline to follow-up. A mixed model analysis of variance reported significant main effect of group on SAD-1 (p = 0.023), SAD-2 (p = 0.010) and mSAD (p = 0.010), with HLG showing lower values compared to CLG. No differences were detected on the LAD (p_FDR = 0.089; d = 0.45), and mSPH (p_FDR = 0.148, d = 0.40) between the two groups. However, a significant main effect of time was found on LAD (p < 0.001), SAD-1 (p < 0.001), SAD-2 (p < 0.001) and mSAD (p < 0.001), with decreased values in all indices at follow-up compared to baseline. A significant group by time interaction was observed on mSPH (p = 0.044); HLG had significantly lower mSPH at follow-up where CLG did not show any significant change. Our findings indicate that although in cirrhotic liver short axis diameter of the MWA zone seems to be significantly longer, this has no effect on the sphericity index which showed no significant difference between cirrhotic vs. healthy liver lesions. On the contrary, on one month follow-up ablation zones tend to become significant more ellipsoid in healthy whilst remains stable in cirrhotic liver.

Percutaneous bipolar radiofrequency ablation for spine metastatic lesions

PURPOSE

The purpose of this review is to become familiar with the most common indications for imaging guided percutaneous bipolar radiofrequency ablation, to learn about different technical considerations during performance providing the current evidence. Controversies concerning products will be addressed.

METHODS

We performed a literature review excluding non-English studies and case reports. All references of the obtained articles were also evaluated for any additional information.

RESULTS

RFA achieves cytotoxicity by raising target area temperatures above 60 °C, and may be used to achieve total necrosis of lesions smaller than 3 cm in diameter, to debulk and reduce the pain associated with larger lesions, to prevent pathological fractures due to progressive osteolysis or for cavity creation aiming for targeted cement delivery in case of posterior vertebral wall breaching. Protective ancillary techniques should be used in order to increase safety and augment efficacy of RFA in the spine.

CONCLUSION

Percutaneous radiofrequency ablation of vertebral lesions is a reproducible, successful and safe procedure. Ablation should be combined with vertebral augmentation in all cases. In order to optimize maximum efficacy a patient- and a lesion-tailored approach should both be offered focusing upon clinical and performance status along with life expectancy of the patient as well as upon lesion characteristics.

Feasibility and safety of percutaneous computed tomography guided radiofrequency ablation of lymph nodes in oligometastatic patients: a single center's experience

OBJECTIVES

To retrospectively evaluate feasibility and safety of CT-guided percutaneous radiofrequency ablation (RFA) of metastatic lymph nodes (LN) in terms of achieving local tumor control.

METHODS

Institutional database research identified 16 patients with 24 metastatic LNs who underwent percutaneous CT-guided radiofrequency ablation. Mean patient age was 66.6 ± 15.70 years (range 40-87) and male/female ratio was 8/8. Contrast-enhanced CT or MRI was used for post-ablation follow-up. Patient and tumor characteristics and RFA technique were evaluated. Technical and clinical success on per tumor and per patient basis as well as complication rates were recorded.

RESULTS

Mean size of the treated nodes was 1.78 ± 0.83 cm. The mean number of tumors per patient was 1.5 ± 0.63. The mean procedure time was 56.29 ± 24.27 min including local anesthesia, electrode(s) placement, ablation and post-procedural CT evaluation. Median length of hospital stay was 1.13 ± 0.34 days. On a per lesion basis, the overall complete response post-ablation according to the mRECIST criteria applied was 75% (18/24) of evaluable tumors. Repeat treatment of an index tumor was performed on two patients (three lesions) with complete response achieved in 87.5% (21/24) of evaluable tumors following a second RFA. On a per patient basis, disease progression was noted in 10/16 patients at a mean of 13.9 ± 6.03 months post the ablation procedure.

CONCLUSION

CT-guided percutaneous RFA for oligometastatic LNs is a safe and feasible therapy.

ADVANCES IN KNOWLEDGE

With this percutaneous therapeutic option, metastatic LNs can be eradicated with a very low complication rate.

The Role of Percutaneous Ablation in the Management of Colorectal Cancer Liver Metastatic Disease

Approximately 50% of colorectal cancer patients will develop metastases during the course of the disease. Local or locoregional therapies for the treatment of liver metastases are used in the management of oligometastatic colorectal liver disease, especially in nonsurgical candidates. Thermal ablation (TA) is recommended in the treatment of limited liver metastases as free-standing therapy or in combination with surgery as long as all visible disease can be eradicated. Percutaneous TA has been proven as a safe and efficacious therapy offering sustained local tumor control and improved patient survival. Continuous technological advances in diagnostic imaging and guidance tools, the evolution of devices allowing for optimization of ablation parameters, as well as the ability to perform margin assessment have improved the efficacy of ablation. This allows resectable small volume diseases to be cured with percutaneous ablation. The ongoing detailed information and increasing understanding of tumor biology, genetics, and tissue biomarkers that impact oncologic outcomes as well as their implications on the results of ablation have further allowed for treatment customization and improved oncologic outcomes even in those with more aggressive tumor biology. The purpose of this review is to present the most common indications for image-guided percutaneous ablation in colorectal cancer liver metastases, to describe technical considerations, and to discuss relevant peer-reviewed evidence on this topic. The growing role of imaging and image-guidance as well as controversies regarding several devices are addressed.

Computed Tomography-Guided Percutaneous Radiofrequency Ablation of the Splanchnic Nerves as a Single Treatment for Pain Reduction in Patients with Pancreatic Cancer

The aim of this paper is to prospectively evaluate the efficacy and safety of percutaneous computed tomography (CT)-guided radiofrequency (RF) neurolysis of splanchnic nerves as a single treatment for pain reduction in patients with pancreatic cancer. Patients with pancreatic ductal adenocarcinoma suffering from abdominal pain refractory to conservative medication who underwent CT-guided neurolysis of splanchnic nerves by means of continuous radiofrequency were prospectively evaluated for pain and analgesics reduction as well as for survival. In all patients, percutaneous neurolysis was performed with a bilateral retrocrural paravertebral approach at T12 level using a 20 Gauge RF blunt curved cannula with a 1cm active tip electrode. Self-reported pain scores were assessed before and at the last follow-up using a pain inventory with numeric visual scale (NVS) units. The mean patient age was 65.4 ± 10.8 years (male-female: 19-11). The mean pain score prior to RF neurolysis of splanchnic nerves was 9.0 NVS units; this score was reduced to 2.9, 3.1, 3.6, 3.8, and 3.9 NVS units at 1 week, 1, 3, 6, and 12 months respectively (p < 0.001). Significantly reduced analgesic usage was reported in 28/30 patients. Two grade I complications were reported according to the Cardiovascular and Interventional Radiological Society of Europe (CIRSE) classification system. According to the results of the present study, solely performed computed tomography-guided radiofrequency neurolysis of splanchnic nerves can be considered a safe and efficacious single-session technique for pain palliation in patients with pancreatic ductal adenocarcinoma suffering from abdominal pain refractory to conservative medication. Although effective in pain reduction the technique seems to have no effect upon survival improvement.

Computed Tomography-Guided Percutaneous Infiltrations for Piriformis Syndrome: A Single-Center Retrospective Study

Piriformis syndrome (PS), first described by Yeoman in 1928, is a general term referring to low back pain, sciatica, and instability. PS has a 6% incidence rate worldwide. In this study, we aim to retrospectively evaluate the effectiveness of computed tomography (CT)-guided percutaneous infiltration in a series of consecutive PS patients who have symptoms that are refractory to conservative therapies. An institutional database search identified 20 such consecutive patients who underwent infiltration with a mixture of long-acting corticosteroid and local anesthetic. Preoperational evaluation included physical examination and magnetic resonance imaging. The correct position of the 22-gauge spinal needle was verified with CT scan after contrast medium injection. Pain measured before the procedure and at 1 wk and 1, 6, and 12 mo after the procedure was compared by means of a numeric visual scale (NVS) questionnaire. The mean pain score before CT-guided percutaneous infiltration was 8.95 ± 1.432 NVS units. This score was reduced to a mean value of 0.85 ± 0.933 units at 1 wk, 0.90 ± 0.852 at 1 mo, 1.10 ± 1.165 at 6 mo, and 1.20 ± 1.399 at 12 mo follow-up (p < 0.001). Two patients of 20 (10%) underwent a second infiltration that was performed at 7 and 10 d after the first, respectively. No complications were observed. CT-guided infiltration seems to be a feasible, efficacious, and safe approach for pain reduction and mobility improvement in patients with symptomatic PS.

Continuous versus pulsed microwave ablation in the liver: any difference in intraoperative pain scores?

Background

This study prospectively compared intraoperative pain scores during percutaneous microwave ablation of the liver in patients randomized between continuous and pulsed energy delivery algorithms.

Methods

During a 12-month period, 20 patients who underwent microwave liver ablation were prospectively randomized between 2 different energy delivery modes: “continuous mode” (CM, n=10) and “pulsed mode” (PM, n=10). All ablation sessions were performed using the same microwave ablation platform under computed tomographic guidance and intravenous analgesia. Within 30 min post ablation, all patients completed a questionnaire assigning a numeric pain intensity score from 0 (no pain) to 10.

Results

Mean pain scores were 8.17±1.850 in the CM group and 4.50±1.567 in the PM group, with a statistically significant difference of 3.667±2.807 pain units (P=0.001). The mean procedure time was 53.5±20.90 min in the PM group vs. 58.5±17.44 min in the CM group (P=0.279). The mean size of the lesions was 2.81±0.95 cm in the PM group and 2.81±0.85 cm in the CM group (P=0.984). On a per-lesion basis, technical success was achieved in all evaluable tumors in both groups. No difference was noted in the local tumor control on the 6-month imaging evaluation. No complications were observed in the CM arm, while small perihepatic hemorrhagic fluid collections were reported in the PM group.

Conclusions

Both algorithms for microwave energy delivery have comparable treatment effects in terms of 6-month local tumor control for liver lesions <3 cm in diameter. PM treatments compared to CM appear to induce significantly less pain in patients undergoing percutaneous liver ablation under intravenous analgesia.

Percutaneous cryoanalgesia for pain palliation: Current status and future trends

Cryoanalgesia, otherwise termed cryoneurolysis, refers to application of extreme cold upon peripheral nerves for palliation of pain associated to nerve lesions or biomechanical syndromes of neoplastic and non-neoplastic substrate. Application of cryoanalgesia initiates a cascade of pathophysiologic events interrupting nerve conduction of painful stimuli without irreversible nerve damage. Cryoanalgesia is considered a safe procedure with minimal risk of complications when performed with percutaneous approaches under imaging guidance. In the era of an opioid overdose crisis, cryoanalgesia can be proposed as an alternative aiming at controlling pain and improving life quality. Imaging guidance has substituted open surgical and nerve stimulation approaches in nerve identification, significantly contributing to the minimally invasive character of percutaneous approaches. Ultrasound or computed tomography can serve as low cost, ideal guiding techniques due to their abilities for precise anatomic delineation, high spatial resolution and good tissue contrast. The purpose of this review is to become familiar with the most common imaging guided percutaneous cryoanalgesia indications, to learn about different technical considerations during performance providing the current evidence. Controversies concerning products will be addressed.

Preliminary Data of a Quantitative Point of Care Test for SARS-CoV-2 Antibodies From Greece

BACKGROUND

Antibody testing is necessary to identify immune individuals in the post-initial wave of the COVID-19 pandemic.

PATIENTS AND METHODS

We prospectively evaluated the performance of a quantitative point-of-care test (POCT) for SARS-CoV-2 antibodies. The patient group (PG) comprised of hospitalized confirmed COVID-19 cases. Asymptomatic healthcare volunteers with negative rRT-PCR were included in the control group (CG). Measurement of IgM and IgG was obtained by dry fluorescence immunoassay.

RESULTS

Twenty-six PG (65.9±15.4 years old, male 57.7%) and 18 CG (45.6±10.1 years old, male 33.3%) were included. By manufacturer's cut-off (≥0.04 mIU/ml), sensitivity and specificity were 73.08% and 88.89% for IgM and 88.46% and 33.33% for IgG, respectively. Estimated areas under the ROC curve were 0.907 and 0.848 for IgM and IgG, respectively. Results were improved using a cut-off of IgM ≥0.05 mIU/ml and IgG ≥0.10 mIU/ml.

CONCLUSION

Using stringent cut-off values, SARS-CoV-2 antibody POCT detects immune people and can be used during socioeconomic normalization of communities.

RADIATION DOSES TO THE EYE LENS AND FOREHEAD OF INTERVENTIONAL RADIOLOGISTS: HOW HIGH AND ON WHAT GROUNDS?

The aim of the study was to measure and evaluate the radiation dose to the eye lens and forehead of interventional radiologists (IRs). The study included 96 procedures (lower-limb percutaneous transluminal angioplasties, embolisations/chemoembolisations and vertebroplasties) performed by 6 IRs. A set of seven thermoluminescence dosemeters was allocated to each physician. The highest dose per procedure was found for the left eye lens of the primary operator in vertebroplasties (1576 μSv). Left and right eye doses were linearly correlated to left and right forehead doses, respectively. A workload-based estimation of the annual dose to participating IRs revealed that the occupational dose limit for the eye lens can be easily exceeded. The left eye dose of ΙRs must be routinely monitored on a personalised basis. Τhe left eye dose measurement provides a reliable assessment of the ipsilateral forehead dose, along with valid estimations for the right eye and right forehead doses.

Computed Tomography-Guided Radiofrequency Thermocoagulation of the Gasserian Ganglion Using an Alternative to Hartel Anterior Approach: A Bicentral Study

BACKGROUND

Trigeminal neuralgia (TN) is associated with multiple mechanisms involving peripheral and central nervous system pathologies. Among percutaneous treatments offered, radiofrequency thermocoagulation (RFT) is associated with longer duration of pain relief. Mostly due to anatomic variation, cannulation of the foramen ovale using the Hartel approach has a failure rate of 5.17%.

OBJECTIVES

To report safety and efficacy of continuous RFT with an alternative to Hartel anterior approach under computed tomography (CT) guidance in patients with classic TN.

STUDY DESIGN

Retrospective institutional database review; bicentral study.

SETTING

Although this was a retrospective database research, institutional review board approval was obtained.

METHODS

Institutional database review identified 10 patients (men 8, women 2) who underwent CT-guided RFT of the Gasserian ganglion. Preoperational evaluation included physical examination and magnetic resonance imaging. Under anesthesiology control and local sterility measures, a radiofrequency needle was advanced, and its approach was evaluated with sequential CT scans. Motor and sensory electrostimulation tests evaluated correct electrode location. Pain prior, 1 week, 1, 3, and 6 months after were compared by means of a numeric visual scale (NVS) questionnaire.

RESULTS

Mean self-reported pain NVS score prior to RFT was 9.2 ± 0.919 units. One week after the RFT mean NVS score was 1.10 ± 1.287 units (pain reduction mean value of 8.1 units). At 3 and 6 months after thermocoagulation the mean NVS score was 2.80 ± 1.549 units and 2.90 ± 1.370 units, respectively. There were no postoperative complications. Three patients experienced facial numbness, which gradually resolved over a period of 1 month.

LIMITATIONS

Retrospective nature; small number of patients; lack of a control group undergoing a different treatment of TN.

CONCLUSIONS

Percutaneous CT-guided RFT of the Gasserian ganglion constitutes a safe and efficacious technique for the treatment of TN, with significant pain relief and minimal complication rates improving life quality in this group of patients.

KEY WORDS

Trigeminal nerve, neuralgia, pain, radiofrequency, ablation, percutaneous, computed tomography, imaging.

Percutaneous imaging-guided techniques for the treatment of benign neuropathic pain

To date, conservative management including physical and/or systemic pharmacologic therapy is considered as the first line approach for the management of neuropathic pain syndromes. In the era of an opioid overdose crisis with an increased concern upon the risks and harms arising from the misuse of medicines for pain management, percutaneous minimally invasive techniques such as nerve infiltrations as well as neurolysis or neuromodulation techniques can be proposed to control pain and improve life quality. Computed tomography can serve as an ideal guiding technique due to its specific characteristics including precise anatomic delineation, high spatial resolution and good tissue contrast. The purpose of this review is to make the reader familiar with the most common indications for minimally invasive imaging-guided techniques in patients with neuralgia and provide current evidence regarding technical considerations.

Two-Center Prospective Comparison of the Trocar and Seldinger Techniques for Percutaneous Cholecystostomy

OBJECTIVE. The purpose of this study is to compare the safety and efficacy of the bedside ultrasound (US)-guided trocar technique versus the US- and fluoroscopy-guided Seldinger technique for percutaneous cholecystostomy (PC). SUBJECTS AND METHODS. This prospective noninferiority study compared the bedside US-guided trocar technique for PC (the trocar group; 53 patients [28 men and 25 women]; mean [± SD] age, 74.31 ± 16.19 years) with the US- and fluoroscopy-guided Seldinger technique for PC (the Seldinger group; 52 patients [26 men and 26 women], mean age, 79.92 ± 13.38 years) in consecutive patients undergoing PC at two large tertiary university hospitals. The primary endpoints were technical success and procedure-related complication rates. Secondary endpoints included procedural duration, pain assessment, and clinical success after up to 3 months of follow-up. RESULTS. PC was successfully performed for all 105 patients. The clinical success rate was similar between the two study groups (86.8% in the trocar group vs 76.9% in the Seldinger group; p = 0.09). Mean procedural time was significantly lower in the trocar group than in the Seldinger group (1.77 ± 1.62 vs 4.88 ± 2.68 min; p < 0.0001). Significantly more procedure-related complications were noted in the Seldinger group than in the trocar group (11.5% vs 1.9%; p = 0.02). Among patients in the Seldinger group, bile leak occurred in 7.7%, abscess formation in 1.9%, and gallbladder rupture in 1.9%. No procedure-related death was noted. Minor bleeding occurred in one patient (1.9%) in the trocar group, but the bleeding resolved on its own. The mean pain score during the procedure was significantly lower in the Seldinger group than in the trocar group (3.2 ± 1.77 vs 4.76 ± 2.17; p = 0.01). At 12 hours after the procedure, the mean pain score was significantly lower for patients in the trocar group (0.78 ± 1.0 vs 3.12 ± 1.36; p = 0.0001). CONCLUSION. Use of the bedside US-guided trocar technique for PC was equally effective as the Seldinger technique but was associated with fewer procedure-related complications, required less procedural time, and resulted in decreased postprocedural pain, compared with fluoroscopically guided PC using the Seldinger technique.

Safety and efficacy of percutaneous microwave ablation for post-procedural haemostasis: a bi-central retrospective study focusing on safety and efficacy

OBJECTIVE

To review safety and efficacy of percutaneous microwave ablation (MWA) for post-procedural haemostasis.

METHODS

Institutional databases retrospective research identified 10 cases of iatrogenic bleeding who underwent percutaneous MWA for post-procedural haemostasis. Ultrasound examination with Doppler and contrast enhancement identified a source of active bleeding prior to ablation; additionally they were used as guiding modality for antenna insertion whilst, post-ablation, assessed the lack of active extravasation. Target locations included liver intercostal space spleen and thyroid gland. Technical success was defined as positioning of the antenna on the desired location. Treatment end point was considered the disappearance of active extravasation in both Doppler imaging and contrast-enhanced ultrasound.

RESULTS

Technical success (i.e. positioning of the antenna on the desired location) was achieved in all cases. No complications were noted. All patients post MWA remained haemodynamically stable with no need for transfusion and were discharged from the hospital the next morning. Imaging and clinical follow-up in all patients before exiting the hospital did not depict any sign of active extravasation or bleeding.

CONCLUSION

Our limited experience reports preliminary data showing that MWA could be added in the armamentarium of percutaneous therapies for iatrogenic bleeding. More prospective studies with larger patient samples are necessary for verification of this technique as well as for drawing broader conclusions in order to evaluate the place of percutaneous ablation in the treatment algorithm of haemorrhage.

ADVANCES IN KNOWLEDGE

Percutaneous ablation might have a role in haemostasis in well-selected cases.

Evaluation of pain reduction and height restoration post vertebral augmentation using a polyether ether ketone (PEEK) polymer implant for the treatment of split (Magerl A2) vertebral fractures: a prospective, long-term, non-randomized study

OBJECTIVES

The purposes of the study were to evaluate the safety and long-term efficacy of augmented vertebroplasty using a polyether ether ketone (PEEK) implant, for the treatment of lumbar or thoracic vertebral fractures (A2 according to the Magerl's AO classification) and to analyze pain reduction, height restoration, and complications during a 2-year follow-up period.

METHODS

Prospective non-randomized evaluation was performed for 21 painful split vertebral fractures (20 patients, 14 females, 6 males; mean age 72.80 ± 10.991) treated with percutaneous vertebral augmentation using a PEEK device, under fluoroscopic guidance. Pain before the procedure and after 6, 12, and 24 months was evaluated using a numeric visual scale (NVS) questionnaire. Imaging was performed by CT and X-rays. The minimum craniocaudal diameter at the level of the fracture and the maximum craniocaudal diameter at the middle of the fractured vertebra were measured. Statistical analysis was performed to evaluate pain decrease and height restoration.

RESULTS

Successful implant positioning was achieved in all cases. No major clinical complications were observed. Comparing the mean pain scores at baseline (8.69 ± 1.138) and the first day after the treatment (1.19 ± 1.424), there was a decrease of 7.50 NVS units (p < 0.001). Minimum and maximum vertebral body heights were increased after the procedure 56.58% and 13.7% respectively (p < 0.001). Both pain relief and height restoration remained statistically significant (p < 0.001) during the follow-up period.

CONCLUSION

A2 Magerl thoracic or lumbar fractures could be successfully treated with PEEK implant-assisted vertebral augmentation. Randomized studies with larger sample sizes should be done to confirm the effectiveness of the technique.

KEY POINTS

• Vertebral augmentation using a PEEK implant for the treatment of A2 Magerl lumbar or thoracic vertebral fractures seems to be effective both in terms of pain reduction and height restoration. • Effects on pain reduction and height restoration have a long-term duration. • The technique seems to be safe for the treatment of A2 Magerl fractures, without major complications in our study group.

Five-Years Outcome Analysis of 142 Consecutive Hepatocellular Carcinoma Patients Treated with Doxorubicin Eluting Microspheres 30-60 μm: Results from a Single-Centre Prospective Phase II Trial

PURPOSE

To assess prospectively long-term results of doxorubicin-loaded HepaSphere 30-60 μm in consecutive patients with hepatocellular carcinoma (HCC) not amenable to curative treatments.

PATIENTS AND METHODS

Single-center study from June 2011 to December 2015 in 151 patients treated with 75 mg of doxorubicin per HepaSphere vial. Baseline: Barcelona Clinic Liver Cancer BCLC A/B was 49.3%/50.7%, and median diameter 6.1 cm (mean 6.7 ± 2.0). Liver function, local response (mRECIST), liver time to progression (LTTP), progression-free survival (PFS), overall survival (OS) and adverse events (AEs) were recorded.

RESULTS

Final analysis included 142 patients with median follow-up of 46.8 months (range 4-72) without grade 4/5 AEs, and 30-day mortality was 0%. Mean number of scheduled treatments was 2.6 (range 1-3) and on demand 3 (range 1-8). Complete response for single tumor ≤ 5 cm was 75.0% and 66.7% for Child A and Child B, while for > 5 cm was 28.6% and 11.8%, respectively. OS was 31.0 months (mean 33.3 ± 15.2; range 8-69), notably for BCLC A 41 months (mean 41.1 ± 15.3; range 13-69) and for BCLC B 26.0 (mean 26.0 ± 10.5; range 8-51). OS at 1, 3 and 5 years: 95.8%, 75.7% and 21.4% for BCLC A, and 94.4%, 36.1% and 2.7% for BCLC B. Median LTTP for BCLC A was 11 months (mean 11.9 ± 4.7; range 3-24) and 7.5 for BCLC B (mean 7.9 ± 2.9). Local response was significant for OS and LTTP (p < 0.0001), while size and lesion number affected LPFS and OS (p < 0.001).

CONCLUSIONS

HepaSphere 30-60 μm loaded with doxorubicin provides a safe and effective treatment option for patients with HCC.

Interventional radiology techniques for pain reduction and mobility improvement in patients with knee osteoarthritis

Osteoarthritis of the knee is the most common cause of chronic knee pain being more prevalent in middle-aged and elderly patients. Symptomatic patients complain of pain and mobility impairment. Therapeutic armamentarium includes physical therapy, oral pharmacologic therapy, intra-articular injections, nerve ablation or modulation, trans-catheter arterial embolization, minimally invasive arthroscopic treatment and partial or total knee arthroplasty. Interventional radiology therapies for knee osteoarthritis include intra-articular injections, neurotomy and neuromodulation techniques as well as transcatheter intra-arterial therapies. These therapies aim to control pain and inflammation, improve mobility and function whilst the novel cell-based therapies have the potential for bone and cartilage regenerative repair facilitating the delay to surgery. The purpose of this review is to illustrate the technical aspects, the indications and the methodology of local therapies for knee osteoarthritis performed by interventional radiologists and provide current evidence.

Bone and Soft-Tissue Biopsies: What You Need to Know

Percutaneous, image-guided musculoskeletal biopsy, due to its minimal invasive nature, when compared with open surgical biopsy, is a safe and effective technique which is widely used in many institutions as the primary method to acquire tissue and bone samples. Indications include histopathologic and molecular assessment of a musculoskeletal lesion, exclusion of malignancy in a bone/vertebral fracture, examination of bone marrow, and infection investigation. Preprocedural workup should include both imaging (for lesion assessment and staging) and laboratory (including coagulation tests and platelet count) studies. In selected cases, antibiotic prophylaxis should be administered before the biopsy. Core needle biopsy of musculoskeletal lesions has a diagnostic accuracy that ranges from 66 to 98% with higher diagnostic yield for lytic, large-size, malignant lesions and when multiple and long specimens are obtained. Reported complication rates range between 0 and 10% and usually do not exceed 5%, with a suggested threshold of 2%. The purpose of this review article is to illustrate the technical aspects, the indications, and the methodology of percutaneous image-guided bone biopsy that will assist the interventional radiologist to perform these minimal invasive techniques.

Computed tomography-guided percutaneous microwave ablation of hepatocellular carcinoma in challenging locations: safety and efficacy of high-power microwave platforms

OBJECTIVE

To evaluate the clinical efficacy/safety of CT-guided percutaneous microwave ablation for HCC in challenging locations using high-power microwave platforms.

MATERIALS AND METHODS

A retrospective review was conducted in 26 patients with 36 HCC tumours in challenging locations (hepatic dome, subcapsular, close to the heart/diaphragm/hepatic hilum, exophytic) undergoing CT-guided percutaneous microwave ablation in a single centre since January 2011. Two different microwave platforms were used both operating at 2.45 GHz: AMICA and Acculis MWA System. Patient demographics including age, sex, tumour size and location, as well as technical details were recorded. Technical success, treatment response, patients survival and complication rate were evaluated.

RESULTS

Treated tumours were located in the hepatic dome (n = 14), subcapsularly (n = 16), in proximity to the heart (n = 2) or liver hilum (n = 2), while two were exophytic tumours at segment VI (n = 2). Mean tumour diameter was 3.30 cm (range 1.4-5 cm). In 3/26 patients (diameter >4 cm), an additional session of DEB-TACE was performed due to tumour size. Technical success rate was 100%; complete response rate was recorded in 33/36 tumours (91.6%). According to Kaplan-Meier analysis, survival rate was 92.3% and 72.11% at 24- and 60-month follow-up, respectively. There were no major complications; two cases of minor pneumothorax and two cases of small subcapsular haematoma were resolved only with observation requiring no further treatment.

CONCLUSION

CT-guided percutaneous microwave ablation for hepatocellular carcinoma tumours in challenging locations and up to 5 cm in diameter can be performed with high efficacy and safety rates.