Combined Vertebral Augmentation and Radiofrequency Ablation in the Management of Spinal Metastases: an Update.

OPINION STATEMENT: Spinal metastases are the most commonly encountered tumour of the spine, occurring in up to 40% of patients with cancer. Each year, approximately 5% of cancer patients will develop spinal metastases. This number is expected to increase as the life expectancy of cancer patients increases. Patients with spinal metastases experience severe and frequently debilitating pain, which often decreases their remaining quality of life. With a median survival of less than 1 year, the goals of treatment in spinal metastases are reducing pain, improving or maintaining level of function and providing mechanical stability. Currently, conventional treatment strategies involve a combination of analgesics, bisphosphonates, radiotherapy and/or relatively extensive surgery. Despite these measures, pain management in patients with spinal metastases is often suboptimal. In the last two decades, minimally invasive percutaneous interventional radiology techniques such as vertebral augmentation and radiofrequency ablation (RFA) have shown progressive success in reducing pain and improving function in many patients with symptomatic spinal metastases. Both vertebral augmentation and RFA are increasingly being recognised as excellent alternative to medical and surgical management in carefully selected patients with spinal metastases, namely those with severe refractory pain limiting daily activities and stable pathological vertebral compression fractures. In addition, for more complicated lesions such as spinal metastasis with soft tissue extension, combined treatments such as vertebral augmentation in conjunction with RFA may be helpful. While combined RFA and vertebral augmentation have theoretical benefits, comparative trials have not been performed to establish superiority of combined therapy. We believe that a multidisciplinary approach as well as careful pre-procedure evaluation and imaging will be necessary for effective and safe management of spinal metastases. RFA and vertebral augmentation should be considered during early stages of the disease so as to maintain the remaining quality of life in this patient population group.

Multidetector (64+) Computed Tomography Angiography of the Lower Limb in Symptomatic Peripheral Arterial Disease: Assessment of Image Quality and Accuracy in a Tertiary Care Setting.

OBJECTIVE: The aim of this study was to evaluate image quality and accuracy of 64+ detector multidetector computed tomography angiography (MDCTA) for hemodynamically significant (≥50%) stenosis in patients with symptomatic peripheral arterial disease (PAD) using digital subtraction angiography as the reference standard. METHODS: This is a retrospective study of 29 patients with PAD (19 men, 10 women) who underwent lower limb MDCTA (64- or 80-detector) and digital subtraction angiography. Image quality and accuracy of MDCTA for hemodynamically significant stenosis were assessed in the infrarenal aorta and 15 lower extremity segments. RESULTS: Four hundred fifty-three segments were adequately visualized at both modalities. Multidetector CTA had 84.8% sensitivity, 87.7% specificity, and 86.3% accuracy for significant stenosis. Accuracy was decreased in the calf when compromising arterial wall calcifications were present versus absent (55.9% vs 82.4%, P < 0.0001). CONCLUSIONS: 64+ MDCTA is accurate in patients with symptomatic PAD. However, diagnostic accuracy in below-knee vessels remains relatively poorer. Alternative imaging modalities should be considered where below-knee disease is suspected.

Evaluating treatment response following locoregional therapy for hepatocellular carcinoma: A review of the available serological and radiological tools for assessment.

Hepatocellular carcinoma (HCC) is an aggressive primary malignancy of the liver and is the third most common cause of cancer-related global mortality. There has been a steady increase in treatment options for HCC in recent years, including innovations in both curative and non-curative therapies. These advances have brought new challenges and necessary improvements in strategies of disease monitoring, to allow early detection of HCC recurrence. Current serological and radiological strategies for post-treatment monitoring and prognostication and their limitations will be discussed and evaluated in this review.

Ultrasound-guided portal vein puncture during Transjugular Intrahepatic Portosystemic Shunt: Technique and experience of a quaternary liver transplant hospital.

INTRODUCTION: Portal hypertension (PH) is associated with complications including refractory ascites and variceal haemorrhage and can be treated endovascularly with a Transjugular Intrahepatic Portosystemic Shunt (TIPS). Portal vein puncture during TIPS using real-time transabdominal ultrasound guidance is one of many portal vein puncture techniques and is seldom used compared with other methods. The purpose of this manuscript is to describe this technique and its associated procedural outcomes at a quaternary liver transplant hospital. METHODS: Clinical data of all patients who underwent ultrasound-guided TIPS at our institution between 1 January 2009 and 1 January 2019 were retrospectively obtained from electronic medical records and reviewed. Patient demographics, indications, procedural outcomes and complications were recorded. RESULTS: Forty-four ultrasound-guided TIPS procedures were performed during the study period. The most common indication for TIPS was refractory ascites (n = 26; 57%) and variceal haemorrhage (n = 12; 26%). Technical success rate was 100%. No intraprocedural complications occurred. Periprocedural complication rate was 35% (n = 16) with encephalopathy (n = 8; 17%) and sepsis (n = 5; 11%) the most common. One patient with sepsis died. No other TIPS-related deaths occurred. Median fluoroscopy time, contrast volume, air kerma and dose area product values for all procedures were 35 minutes (IQR 24-51), 100 ml (IQR 70-160), 0.95 Gy (IQR 0.50-1.53) and 127 Gycm2 (IQR 68.75-206), respectively. CONCLUSION: Transabdominal ultrasound-guided portal vein puncture during TIPS is safe and technically feasible. When compared to fluoroscopically guided methods, it is associated with lower intraprocedural complication rates, fluoroscopy times, contrast volumes and radiation doses in our experience. Radiation doses, FTs and contrast volumes were also considerably lower than recommended limits.

STABILISE; treatment of aortic dissection, a single Centre experience.

PURPOSE: To outline the process of the STABILISE technique and its use; reporting patient outcomes and midterm follow up for complicated aortic dissection. MATERIALS AND METHODS: Single centre retrospective analysis from January 2011 to January 2021 using the STABILISE technique which utilises balloon assistance to facilitate intimal disruption and promote aortic relamination. RESULTS: Sixteen patients underwent endovascular aortic repair with the STABILISE technique for aortic dissection over the study period. Fourteen patients (14/16; 88%) had acute dissection. Two of 16 (12%) were chronic. The median age of the patient cohort was 61 years (range 32-80 years) and consisted of a male majority (n = 11; 69%). The median time from diagnosis to intervention was 5 days (1-115 days; IQR 1-17.3). More than half (56%) had surgical repair of a acute type A aortic dissection prior to radiological intervention. The procedure was technically successful with no procedural mortality. Two patients were lost to follow up and two died in the post-operative period. Twelve patients had ongoing follow up with an average number of 2.9 ± 1.6 scans performed. Follow up was available in thirteen patients (81%) with a median follow up period of 1097 days (IQR 707-1657). The rate of re-intervention (n = 2/16; 13%) requiring additional stenting was in line with published re-intervention data (15%). Follow up showed a reduction in false lumen size following treatment with total luminal dimensions remaining stable over the follow-up period. CONCLUSION: The STABILISE technique as a procedure for complicated aortic dissection, either acute or chronic, appears safe with stable mid-term aortic remodelling and patient outcomes. LEVEL OF EVIDENCE: Level 3, Retrospective cohort study.

Endovascular balloon-assisted liquid embolisation of soft tissue vascular malformations: technical feasibility and safety.

PURPOSE: Arteriovenous malformations (AVMs) are abnormal communications between arteries and veins without an intervening capillary system. The best endovascular treatment option for these is unclear and may involve multiple staged procedures using a variety of embolic materials. We report our initial experience using a modified version of a previously published neurointerventional technique to treat soft tissue AVMs with single-stage curative intent. MATERIALS AND METHODS: Soft tissue AVMs treated endovascularly using either sole arterial or combined arterial and venous balloon-assisted techniques with liquid embolic agents were retrospectively identified over a 3.5 year period (January 2017 to June 2020)) at two centres. Clinical, pre-operative radiological, procedural technical and post treatment details were recorded. RESULTS: Seven patients were treated for symptomatic soft tissue arteriovenous malformations. These AVMs were located in the peripheral limbs (five), tongue (one) and uterus (one). Curative treatment was achieved in 6/7 patients with one patient requiring a second treatment approximately 1 year later. A variety of liquid embolisation agents (LEAs) including sclerosants and polymers were used. Clinical success rate was 100% following treatment. One patient experienced expected temporary post-operative tongue swelling requiring tracheostomy occurred following embolisation of the lingual AVM. A minor complication in a second patient was due to an access site haematoma developed following treatment of the hand AVM requiring surgical intervention. No long-term sequelae or additional complications were observed. CONCLUSION: Endovascular arterial and venous balloon assisted LEA embolization of soft tissue AVMs with curative intent is feasible. This technique may provide an alternative treatment option for achieving durable occlusion for complex soft tissue AVMs.

Endovascular flow-diversion of visceral and renal artery aneurysms using dual-layer braided nitinol carotid stents.

BACKGROUND: Visceral and renal artery aneurysms (VRAAs) are uncommon but are associated with a high mortality rate in the event of rupture. Endovascular treatment is now first line in many centres, but preservation of arterial flow may be difficult in unfavourable anatomy including wide necked aneurysms, parent artery tortuosity and proximity to arterial bifurcations. Endovascular stenting, and in particular flow-diversion, is used in neurovascular intervention to treat intracranial aneurysms but is less often utilised in the treatment of VRAAs. The CASPER stent is a low profile dual-layer braided nitinol stent designed for carotid stenting with embolic protection and flow-diversion properties. We report the novel use of the CASPER stent for the treatment of VRAAs. We present a case series describing the treatment of six patients with VRAAs using the CASPER stent. RESULTS: Six patients with unruptured VRAAs were treated electively. There were three splenic artery aneurysms and three renalartery aneurysms. Aneurysms were treated with the CASPER stent, with or without loose aneurysm coil packing or liquid embolic depending on size and morphology. All stents were successfully deployed with no immediate or periprocedural complications. Four aneurysms completely occluded after serial imaging follow up with one case requiring repeat CASPER stenting for complete occlusion. In one patient a single aneurysm remained patent at last follow up, A single case was complicated by delated splenic infarction and surgical splenectomy. CONCLUSION: Preliminary experience with the CASPER stent suggests it is technically feasible and effective for use in the treatment of VRAAs.

Accuracy of non-contrast quiescent-interval single-shot and quiescent-interval single-shot arterial spin-labelled magnetic resonance angiography in assessment of peripheral arterial disease in a diabetic population.

INTRODUCTION: Diabetic patients with peripheral arterial disease (PAD) are challenging to assess. Non-contrast magnetic resonance angiography (MRA) offers a safe alternative in patients with renal impairment. The study objective is to evaluate accuracy of lower limb quiescent-interval single-shot (QISS) MRA and pedal QISS-arterial spin-labelled (ASL) MRA for detection of significant stenosis in diabetic patients with PAD. METHODS: Combined QISS and QISS-ASL MRA was performed in 32 diabetic PAD patients (20 male, 12 female; mean 69 years; 8 with critical ischaemia). Two readers assessed haemodynamically significant (>50%) stenosis and diagnostic confidence on MRA, against digital subtraction angiography (DSA) as the reference standard, with subgroup analysis of patients with severe renal impairment (n = 7). Inter-reader agreement of stenosis and diagnostic confidence were evaluated. Test-retest reproducibility was evaluated in 10 subjects who underwent repeat MRA on a different day. RESULTS: At DSA, 262/645 segments (40.6%) had haemodynamically significant stenoses. MRA accuracy was 78.1% (478/612) and 75.6% (464/614), sensitivity 64.7% (161/249) and 77.5% (193/249), and specificity 87.3% (317/363) and 74.2% (271/365) for 2 readers. MRA accuracy was 80.9% and 80.7% for readers 1 and 2, respectively, in patients with severe renal impairment. QISS MRA but not pedal QISS-ASL MRA was considered of diagnostic image quality. Inter-reader agreement was moderate for stenosis (ĸ = 0.60) and diagnostic confidence (ĸ = 0.41). Test-retest reproducibility was high (ĸ = 0.87) and moderate (ĸ = 0.54) for individual readers. CONCLUSIONS: Quiescent-interval single-shot MRA has reasonable accuracy in a diabetic PAD population with high burden of disease, providing a non-contrast option in patients with renal impairment. QISS-ASL MRA requires further optimisation to be clinically feasible.

Percutaneous transhepatic laser lithotripsy for intrahepatic cholelithiasis: A technical report.

Advances in interventional radiology have seen the adaptation of urological endoscopic laser techniques to treat biliary tract calculi. Percutaneous transhepatic biliary laser lithotripsy provides an effective alternative procedure for the management of intrahepatic or conventionally refractory choledocholithiasis which would otherwise require invasive and high-risk surgical intervention. Several small studies have validated the procedure for management in this subset of patients, with most achieving 100% calculi clearance with minimal complications. Most patients are suitable for percutaneous transhepatic biliary laser lithotripsy. Preprocedural imaging is useful for evaluating stone burden and planning percutaneous access. Holmium lasers are commonly used and act by vaporising water particles on and in the calculi, fragmenting the stone via thermal expansion. A series of catheters, wires, sheaths and dilators are used to allow introduction of the choledochoscope and laser so that calculi can be targeted. Percutaneous transhepatic biliary laser lithotripsy is often used in conjunction with balloon dredging and biliary stricture dilatation. Only experienced interventionalists should perform this procedure, and users should be aware of associated hazards. Repeat percutaneous transhepatic cholangiography is routinely performed to confirm eradication of stones. Treatment of biliary calculi and obstruction is important in preventing diseases such as cholangitis and cirrhosis. For patients unsuitable for conventional treatment, percutaneous transhepatic laser lithotripsy is a safe and effective alternative when performed by experienced interventional radiologists. Preprocedural planning is imperative to procedure success.

Vertebroplasty for acute painful osteoporotic vertebral compression fractures: An update.

Vertebral compression fractures (VCFs) are a common cause of back pain and disability and are usually osteoporotic in nature. Therapy aims to adequately control pain and allow early mobilisation and return of function while preventing additional fractures. A proportion of patients do not achieve adequate pain relief using conservative measures alone. Unwanted adverse effects from medications may also ensue. Vertebroplasty represents an alternative treatment option for VCFs. Patients with acute VCFs (≤6 weeks old) may gain the most benefit from vertebroplasty as healed fractures are not as amenable to cement injection. High-quality studies have reported conflicting results regarding the use of vertebroplasty in the treatment of acute VCFs. Despite high-quality evidence, varying study designs and heterogenous patient cohorts make interpretation of this data difficult. Only one sham-controlled randomised controlled trial (RCT) has evaluated vertebroplasty exclusively in patients with acute VCFs, reporting favourable results. Pooled data from RCTs also suggest vertebroplasty to be safe. This article provides a concise and critical review of the current literature regarding vertebroplasty for the treatment of acute VCFs.

Endovascular treatment of visceral artery and renal aneurysms (VRAA) using a constant mesh density flow diverting stent.

BACKGROUND: Flow diverting stents have been used safely and effectively for the treatment of intracranial aneurysms, particularly for large and wide necked aneurysms that are not amenable to conventional endovascular treatment with coiling. The Surpass Streamline device (Stryker Neurovascular, MI, USA) is a relatively new and unique flow diverting stent which maintains constant device mesh density over varying vessel diameters. This may potentially provide advantages compared to other flow diverting stents in achieving aneurysmal occlusion. CASE PRESENTATION: Two patients with VRAA were treated using the Surpass Streamline device. The first patient was a 65-year-old male with an incidental 2.4 cm aneurysm originating from the hepatic artery near the gastroduodenal artery (GDA). The second patient was a 56-year-old male with an incidental 1.9 cm renal aneurysm arising from an anterior inferior segmental branch of the left renal artery. A Surpass flow diverting stent was used to successfully exclude the aneurysm neck in both cases. Reduced flow was achieved in one patient (equivalent to O'Kelly-Marotta [OKM] Grade B1). Preserved flow and stagnation (equivalent to OKM Grade A3) was achieved in the other. There was preserved distal flow in the parent arteries. No immediate complications were encountered in either case. Complete occlusion of both aneurysms was seen on follow up CT angiographic imaging within 8-weeks. CONCLUSIONS: The Surpass flow diverting stent can be used safely and effectively to treat VRAA. It should be considered in unruptured large and giant wide necked VRAAs aneurysms. Additional large prospective studies are required for further validation.

Upper extremity non-contrast magnetic resonance venography (MRV) compared to contrast enhanced MRV and ultrasound.

PURPOSE: To assess feasibility, image quality and measured venous caliber of non-contrast MRV (NC-MRV) of central and upper extremity veins, compared to contrast-enhanced MRV (CE-MRV) and ultrasound (US) in healthy volunteers. MATERIALS AND METHODS: 10 subjects underwent NC-MRV and CE-MRV at 1.5 T, with comparison to US. Two radiologists evaluated MRI for image quality (IQ) and venous caliber. RESULTS AND CONCLUSIONS: NC-MRV is feasible, with inferior IQ but comparable venous caliber measurements CE-MRV (mean 7.9±4.58 mm vs. 7.83±4.62, p=0.13). Slightly larger upper limb caliber measurements were derived for NC-MRV and CE-MRV compared to US (NC-MRV 5.2±1.8 mm, CE-MRV 4.9±1.6 mm, US 4.5±1.8 mm, both p<0.001).

The future of interventional and neurointerventional radiology: learning lessons from the past.

The rapid progression of medical imaging technology and the ability to leverage knowledge from non-invasive imaging means that Interventional Radiologists (IRs) and Interventional Neuroradiologists are optimally placed to incorporate minimally invasive interventional paradigms into clinical management to advance patient care. There is ample opportunity to radically change the management options for patients with a variety of diseases through the use of minimally invasive interventional procedures. However, this will need to be accompanied by an increased clinical role of IRs to become active partners in the clinical management of patients. Unfortunately, the development of IR clinical presence has lagged behind and is reflected by declining rates of IR involvement in certain areas of practice such as vascular interventions. Current and future IRs must be willing to take on clinical responsibilities; reviewing patients in clinic to determine suitability for a procedure and potential contraindications, rounding on hospital inpatients and be willing to manage procedure related complications, which are all important parts of a successful IR practice. Increasing our clinical presence has several advantages over the procedure-driven model including enhanced patient knowledge and informed consent for IR procedures, improved rapport with patients and other clinical colleagues through active participation and engagement in patient care, visibility as a means to facilitate referrals and consistency of follow-up with opportunities for further learning. Many of the solutions to these problems are already in progress and the use of IR as a "hired gun" or "technician" is a concept that should be relegated to the past, and replaced with recognition of IRs as clinicians and partners in delivering modern high quality multidisciplinary team-based patient care. The following article will review the history of IR, the challenges facing this rapidly evolving profession and discuss recent developments occurring globally that are essential in maintaining expertise, securing future growth and improving patient outcomes in the modern multidisciplinary practice of medicine.

Endovascular Treatment of Wide-Necked Visceral Artery Aneurysms Using the Neurovascular Comaneci Neck-Bridging Device: A Technical Report.

INTRODUCTION: Visceral and renal artery aneurysms (VRAAs) are an uncommon clinical entity but carry a risk of rupture with associated morbidity and mortality. The rupture risk is particularly high when the aneurysms are large, of unfavourable morphology or in the setting of pregnancy and perioperative period. Endovascular approaches are now first line in the treatment of VRAA, but conventional techniques may be ineffective in excluding aneurysms with unfavourable anatomy such as those with wide necks or at arterial bifurcation points. The neurovascular Comaneci neck-bridging device is used to temporarily cover the neck of intracranial aneurysms without occluding forward arterial flow during endovascular coiling. We report the novel use of the Comaneci neck-bridging device for the treatment of complex peripheral VRAAs. MATERIALS AND METHODS: We describe the treatment of two patients with renal and splenic artery aneurysms demonstrating unfavourable anatomic morphology for conventional endovascular approaches. RESULTS: In the first patient, the renal artery aneurysm was situated at the intrarenal bifurcation of the main renal artery in the setting of a solitary kidney. In the second patient, the splenic artery aneurysm was situated close to the splenic hilum at the distal splenic arterial bifurcation. The Comaneci neck-bridging device was successfully used in both cases to assist coil embolisation with visceral preservation. CONCLUSIONS: The Comaneci neck-bridging device is potentially safe and effective for the treatment of peripheral VRAA with unfavourable anatomic characteristics that would have been deemed unsuitable for treatment using conventional techniques. LEVEL OF EVIDENCE: Level 4, Technical Report.