Impact of the COVID-19 pandemic on interventional radiology services across the world

AIM

To review data on the impact of the COVID-19 pandemic on interventional radiology (IR) services.

MATERIALS AND METHODS

A systematic review of the available studies was performed according to the PRISMA guidelines.

RESULTS

A total of 14 studies met the inclusion criteria. IR caseload reduced between 16.8-80%, with elective activity affected more than emergency work. Trainees also experienced a 11-51.9% reduction in case volumes and many were redeployed to critical care. IR departments re-organised operations and personnel, and many continued to offer 24/7 services and support critical care areas through redeployment of staff. The majority of studies report no significant issues with the availability of personal protective equipment and that local or national governing body or radiology society guidelines were followed.

CONCLUSION

The COVID-19 pandemic reduced case volumes and training opportunities. IR departments showed flexibility in service delivery. The lessons learned offer novel insights into how services and training can be reorganised to ensure that IR continues to thrive.

Systematic review and meta-analysis of thermal ablation versus surgical nephrectomy for small renal tumours

PURPOSE

A systematic review was undertaken to provide a meta-analysis of clinical trials comparing thermal ablation with surgical nephrectomy for small renal tumours.

METHODS

PubMed (MEDLINE), EMBASE, AMED, and Scopus were searched in August 2013 for eligible prospective or retrospective comparative trials following the PRISMA selection process. Thermal ablation was compared with surgical nephrectomy. Quality of included studies was assessed on the Newcastle-Ottawa Scale (NOS). The primary endpoint was disease-free survival and was analyzed on the log-hazard scale. Secondary outcome measures included complications, local recurrence, and decline of renal function. Hazard ratios (HR) and risk ratios (RR) were calculated with a random effects model, and meta-regression analysis was performed to explore clinical heterogeneity.

RESULTS

Six clinical trials (1 randomized and 5 cohort; 6-8 stars on the NOS scale) involving 587 patients with small renal tumors (mean size 2.5 cm) treated with either thermal ablation (percutaneous or laparoscopic application of radiofrequency or microwave) or surgical nephrectomy (open or laparoscopic) were analyzed. Overall complication rate was significantly lower in the ablation group (7.4 vs. 11%; RR: 0.55, 95% confidence interval [CI]: 0.31-0.97, p = 0.04). Postoperative decline of eGFR was higher in case of nephrectomy (mean difference: -14.6 ml/min/1.73 m(2), 95% CI: -27.96 to -1.23, p = 0.03). Local recurrence rate was the same in both groups (3.6 vs. 3.6%; RR: 0.92, 95% CI: 0.4-2.14, p = 0.79) and disease-free survival also was similar up to 5 years (HR: 1.04, 95% CI: 0.48-2.24, p = 0.92).

CONCLUSIONS

Thermal ablation of small renal masses produces oncologic outcomes similar to surgical nephrectomy and is associated with significantly lower overall complication rates and a significantly less decline of renal function. More randomized, controlled trials are necessary.

Fluoroscopically guided balloon dilatation for the treatment of achalasia: long-term outcomes

To report the immediate and long-term outcomes following the fluoroscopically guided balloon dilatations performed in our department for the treatment of achalasia. We reviewed retrospectively all patients that underwent a fluoroscopically guided balloon dilatation because of achalasia in our department between April 2007 and September 2010. The follow-up was performed by interviews and/or investigation of the patient's medical and imaging records. The primary endpoints of the study were technical success, clinical success, major complication rates, and repeat dilatation rates because of recurrence of clinical symptomatology. Secondary endpoints were the rate of minor complications and the dilatation-free interval. Various parameters that could affect the clinical outcome were also analyzed. Thirty-nine consecutive patients (20 female) with a mean age 44 ± 17 years underwent 69 dilatations, while 10/39 (25.6%) patients had a history of a previous laparoscopic myotomy. The most common symptom was dysphagia (64/69, 92.7%), while regurgitation and/or retrosternal pain were present in 12/39 (30.7%) and 9/39 (23%) of the cases, respectively. Technical success was achieved in 98.5% (68/69). There were no procedure-related major complications. The mean balloon diameter used was 30 ± 3.9 mm, and the mean period of follow-up was 27.7 ± 16.0 months. Excellent or good initial responses were noted in 54/66 cases (81.8%). A repeated dilatation to deal with recurrence of symptoms was performed in 69.4% of the cases (25/36). In the majority of the cases, two dilatations were needed in order to achieve long-term relief from symptoms. A dilatation-free interval of 4 years was observed in 26.4%. Clinical success was achieved in 30/36 patients (83.3%). Subgroup analysis did not detect significantly different recurrence rates in patients with and without previous laparoscopic myotomy (50% vs. 69% respectively), those of young age (75% < 21 years vs. 68.8% > 21 years), and male gender (71.4% male vs. 55.0% females). The high redilatation rate was attributed to the utilization of smaller balloons by less experienced operators. Fluoroscopically guided balloon dilatation is a safe and effective method for the treatment of achalasia. Young age and prior Heller's laparoscopic myotomy were not associated with increased rates of recurrence rate or clinical failure.

Endovascular treatment of isolated iliac artery aneurysms using a custom-made stent graft with proximal barb fixation: early outcome

Current endovascular treatments for isolated iliac artery aneurysms (IIAAs) include the use of aortoiliac stent grafts with coverage of the distal aorta or stent grafts confined to the iliac artery without active proximal fixation. We report our experience in the use of custom-made Cook Zenith™ iliac limb stent grafts with proximal barb fixation. Patients treated from July 2009 to February 2011 were included. All imaging and patient records were assessed for perioperative and early outcomes. Nine IIAAs (seven patients) were treated. The mean patient age was 80 years (range 58-91 years). The mean aneurysm size was 48 mm (35-80 mm), and the mean length of the proximal landing zone (PLZ) was 29 mm (10-50 mm). The distal landing zone was in the external iliac artery after coil embolization of the internal iliac artery. The Mean diameter of the PLZ was 21 mm (20-24 mm). Technical success was achieved in eight cases. Perioperative complications included reoperation in one patient for groin bleeding and ischemia. On follow-up (mean 12 months, range 1-26), all aneurysms were successfully excluded from the circulation and there was no stent graft migration or thrombosis. Use of custom-made stent grafts with proximal barb fixation in treatment of IIAAs is a feasible option which may reduce the risk of migration when compared with stent grafts with lack of proximal fixation.

Percutaneous balloon venoplasty of pacemaker-associated superior vena cava obstruction to facilitate upgrade to a biventricular pacing system

Superior vena cava (SVC) obstruction is an uncommon, but serious, complication of transvenous device implantation. We present a case of a 52-year-old lady admitted for upgrade to a biventricular pacemaker with significant SVC stenosis. Percutaneous balloon venoplasty of the SVC followed by insertion of biventricular pacing leads was carried out as a single procedure with no complications.

Percutaneous biliary internal decompression in a patient with simultaneous malignant biliary and duodenal obstruction and surgically modified anatomy

Simultaneous involvement and obstruction of the common bile duct and the duodenum presents a difficult and challenging problem to the surgeon, the endoscopist and the interventional radiologist. In the case report we present here, the patient had had duodenal and biliary obstruction secondary to hepatic flexure adenocarcinoma and presented with recurrent obstructive jaundice. As the surgically modified anatomy precluded all conventional endoscopic and percutaneous approaches, it was necessary to use an improvised method of achieving biliary decompression.

Neurological Complications Following Endoluminal Repair of Thoracic Aortic Disease

Open surgery for thoracic aortic disease is associated with significant morbidity and the reported rates for paraplegia and stroke are 3%-19% and 6%-11%, respectively. Spinal cord ischemia and stroke have also been reported following endoluminal repair. This study reviews the incidence of paraplegia and stroke in a series of 186 patients treated with thoracic stent grafts. From July 1997 to September 2006, 186 patients (125 men) underwent endoluminal repair of thoracic aortic pathology. Mean age was 71 years (range, 17-90 years). One hundred twenty-eight patients were treated electively and 58 patients had urgent procedures. Anesthesia was epidural in 131, general in 50, and local in 5 patients. Seven patients developed paraplegia (3.8%; two urgent and five elective). All occurred in-hospital apart from one associated with severe hypotension after a myocardial infarction at 3 weeks. Four of these recovered with cerebrospinal fluid (CSF) drainage. One patient with paraplegia died and two had permanent neurological deficit. The rate of permanent paraplegia and death was 1.6%. There were seven strokes (3.8%; four urgent and three elective). Three patients made a complete recovery, one had permanent expressive dysphasia, and three died. The rate of permanent stroke and death was 2.1%. Endoluminal treatment of thoracic aortic disease is an attractive alternative to open surgery; however, there is still a risk of paraplegia and stroke. Permanent neurological deficits and death occurred in 3.7% of the patients in this series. We conclude that prompt recognition of paraplegia and immediate insertion of a CSF drain can be an effective way of recovering spinal cord function and improving the prognosis.

Large infra-renal abdominal aortic aneurysms: endovascular vs. open repair--single centre experience

Endovascular aneurysm repair (EVAR) has become an established alternative to open repair (OR). We present a consecutive series of 486 elective patients with large infra-renal aortic abdominal aneurysm, comparing OR with EVAR. Prospective data collected during an 8-year period from January 1997 to October 2005 was reviewed. Statistical analysis performed using SPSS data editor with chi(2) tests and Mann-Whitney U-tests. There were 486 patients with 329 OR (293 males, 36 females) with median age of 72 years with median diameter 6.3 cm and 157 EVAR (148 males, 9 females) with median age 75 years with median diameter 6.1 cm. Mortality was 13 (4%) for OR and 5 (3.2%) for EVAR (three of whom were in the UK EVAR 2 trial). Blood loss was significantly less for EVAR 500 ml vs. 1500 ml for OR. Sixty-five (19.8%) patients with OR had significantly more peri-operative complications compared with 14 (8.9%) with EVAR. The length of stay in hospital was significantly less for EVAR. This non-randomised study shows that although EVAR does not have a statistically significantly lower mortality, it does have statistically significantly lower complication rates compared with OR. EVAR can be achieved with good primary success, but long-term follow-up is essential to assess durability.

Successful stent-graft placement for the treatment of a superior gluteal artery pseudoaneurysm in a patient following complex pelvic surgery

Aneurysms of the gluteal arteries are rare and were previously managed with open surgical procedures. Recently percutaneous embolisation techniques have helped reduce morbidity and mortality. A case is presented of a 63-year-old man who presented with haemorrhage and had developed a superior gluteal artery aneurysm following treatment for an invasive squamous cell carcinoma in the sacral area. There was concern that embolisation of the aneurysm might compromise the survival of the myocutaneous buttock rotation flaps that had been used for reconstruction. To overcome this, an endovascular stent was deployed to successfully close off the aneurysm whilst at the same time maintaining blood flow through the superior gluteal artery. Aneurysms in larger peripheral vessels have been managed with stents. However, this is the first reported case of this method of treatment being used in the management of gluteal artery aneurysms.

Endocarditis and ulnar artery aneurysm as presenting features of antiphospholipid syndrome and polyarteritis nodosa

Antiphospholipid syndrome in association with vasculitis is highlighted in this report. The combination of thrombotic and inflammatory processes resulted in endocarditis, aneurysm formation and thrombosis. To our knowledge this is the first presentation of a large vessel aneurysm in these conditions. Anticoagulation and immunosuppression are the treatment modalities of choice.

Sequential cohort study of Dacron patch closure following carotid endarterectomy

BACKGROUND

Carotid endarterectomy reduces the risk of stroke and death in patients with severe carotid artery stenosis. This study examined whether the technique used to close the arteriotomy influenced the rate of perioperative transient ischaemic attack (TIA), stroke or death.

METHODS

A cohort of 236 patients undergoing carotid endarterectomy at a single centre was studied; 117 patients had primary closure of the arteriotomy and 119 patients in a sequential series had closure with a Dacron patch. A standard endarterectomy with completion intraoperative duplex imaging and digital subtraction angiography was used throughout.

RESULTS

Patch closure was associated with a significant reduction in the 30-day combined death, stroke and TIA rate: 10.3 per cent for primary closure versus 2.5 per cent for patch closure (P = 0.017). The risk of any cerebral event (stroke or TIA) was also significantly reduced (7.7 versus 1.7 per cent; P = 0.033). Residual stenosis on completion angiography was more common after primary closure (24.6 versus 7.4 per cent; P = 0.003).

CONCLUSION

Dacron patch closure had a higher technical success rate on completion imaging and was associated with a significant reduction in the risk of perioperative stroke, TIA and death.

Successful treatment of a chronic post-traumatic 5-year-old osteoporotic vertebral compression fracture by percutaneous vertebroplasty

Osteoporotic vertebral compression fracture (VCF) is a frequently encountered clinical problem associated with chronic pain and disability. Conservative treatment in the form of bed rest, pain control and bracing may create a vicious circle, in which reduced activity leads to further reduction in bone density and fracture risk. Percutaneous vertebroplasty (PVP) is an accepted treatment modality for osteoporotic vertebral body collapse present for less than 1 year, vertebral myeloma, haemangioma, metastasis and recent traumatic fractures (between 3 and 12 months). We describe an osteoporotic patient in whom successful PVP was performed, under general anaesthesia using CT and fluoroscopic guidance, in a post-traumatic 5-year-old VCF with complete alleviation of debilitating pain. In the light of our experience, we suggest that PVP should be carried out in a series of similar patients to asses its value as a treatment option in patients with chronic osteoporotic vertebral fractures for pain relief and improvement in mobility, independent of fracture age.

Treatment of Mycotic Aortic Aneurysms with Endoluminal Grafts

PURPOSE

To report the benefit of endoluminal repair of mycotic aortic aneurysms and highlight the need for a registry.

METHODS

Nine patients (five female) were identified over 5 years (1998-2003) as having presumed mycotic aortic aneurysms (12 in total) suitable for endoluminal grafting. A total of nine thoracic and three abdominal were grafted and followed up for a median of 36 months.

RESULTS

Six of the aneurysms have resolved and one was converted to an open repair. There was one early death from rupture of a second undiagnosed aneurysm and two late deaths from rupture due to persistent inflammation. Long-term antibiotics have not been mandatory to ensure survival.

CONCLUSIONS

Mycotic aortic aneurysms of the thoracic and abdominal aorta do benefit from endoluminal repair, particularly when arising in previously normal aortic tissue. Endoluminal grafting also has a role in the palliation of secondarily infected aortas and so to prove its efficacy in the treatment of all these rare cases a registry is required.

Endovascular repair of a ruptured abdominal aortic aneurysm under local anaesthesia

Abdominal aortic aneurysm (AAA) is a common degenerative condition affecting the elderly population. Rupture carries a high overall mortality. Elective endovascular stent graft repair is well described. We describe a patient with ruptured AAA and co-morbid conditions making him unfit for surgery and general or epidural anaesthesia, who was successfully treated by endovascular stent graft under local anaesthesia.

The use of SMARTeR stents in patients with biliary obstruction

AIM

The purpose of the study was to evaluate the percutaneous use of the new nitinol SMARTeR stents in patients with biliary obstruction.

MATERIALS AND METHODS

Four stents were placed in three patients percutaneously under ultrasound and fluoroscopic guidance.

RESULTS

The deployment of the stents was successful in all three patients. All stents maintained their patency and position after short-term follow-up.

CONCLUSION

The nitinol SMARTeR stent is useful in the management of patients with biliary obstruction although accurate placement across the ampulla was found to be technically more difficult than with the Wallstent. Larger, long-term follow-up studies are required to evaluate the long-term patency of these new devices.

Registration of freehand 3D ultrasound and magnetic resonance liver images

We present a method to register a preoperative MR volume to a sparse set of intraoperative ultrasound slices. Our aim is to allow the transfer of information from preoperative modalities to intraoperative ultrasound images to aid needle placement during thermal ablation of liver metastases. The spatial relationship between ultrasound slices is obtained by tracking the probe using a Polaris optical tracking system. Images are acquired at maximum exhalation and we assume the validity of the rigid body transformation. An initial registration is carried out by picking a single corresponding point in both modalities. Our strategy is to interpret both sets of images in an automated pre-processing step to produce evidence or probabilities of corresponding structure as a pixel or voxel map. The registration algorithm converts the intensity values of the MR and ultrasound images into vessel probability values. The registration is then carried out between the vessel probability images. Results are compared to a "bronze standard" registration which is calculated using a manual point/line picking algorithm and verified using visual inspection. Results show that our starting estimate is within a root mean square target registration error (calculated over the whole liver) of 15.4 mm to the "bronze standard" and this is improved to 3.6 mm after running the intensity-based algorithm.

Bronchogastric fistula successfully treated with the insertion of a covered bronchial stent

We present what we believe to be the first case of a bronchogastric fistula successfully treated with a plastic-covered metallic bronchial stent. This developed 5 years after a transhiatal oesophagectomy with gastric pull-up for carcinoma of the oesophagus. The successful outcome in this case suggests that this method of treatment should be considered in patients in whom this post-operative complication cannot be managed easily by other means.

Mid-term results for second-generation thoracic stent grafts

BACKGROUND

Thoracic stent grafts offer an alternative to open surgery for thoracic aortic disease, but their long-term durability is unknown. This report includes mid-term follow-up for commercially available thoracic devices.

METHODS

Data were collected prospectively for a series of endoluminal grafts used to treat thoracic aortic pathology.

RESULTS

Between July 1997 and October 2002, 67 patients received thoracic stent grafts. Elective procedures incurred a 30-day mortality rate of 2 per cent (one of 42 patients) and urgent repair 16 per cent (four of 25). Paraplegia affected three (4 per cent) of 67 patients and three patients had a stroke. The median follow-up was 17 (range 2-64) months; four patients were lost. There were six late deaths, two from aneurysm rupture (rupture of a mycotic aneurysm at 5 months and stent migration at 28 months). Other device-related complications comprised three proximal endoleaks, one of which required open surgical correction with removal of the stent graft, and two distal endoleaks, which were successfully treated with distal extension cuffs.

CONCLUSION

In the mid term, endoluminal repair of thoracic aortic pathology appears to be a safe alternative to open surgery, but continued surveillance is essential.

A randomised prospective comparison of the Flamingo Wallstent and Ultraflex stent for palliation of dysphagia associated with lower third oesophageal carcinoma

BACKGROUND

Covered metallic oesophageal stents offer effective palliation of malignant oesophageal strictures. However, first generation devices were associated with a high rate of migration, particularly when used in the lower oesophagus.

AIM

To compare the rate of complications and palliative effect of two newer covered metallic oesophageal stents.

PATIENTS AND METHODS

We performed a prospective randomised study using two of these newer stent designs in the treatment of malignant lower third oesophageal tumours. Fifty three patients with dysphagia due to inoperable oesophageal carcinoma involving the lower third of the oesophagus were randomly selected to receive either a Flamingo covered Wallstent (Boston Scientific Inc., Watertown, Massachusetts, USA) or an Ultraflex covered stent (Boston Scientific Inc.). Dysphagia was scored on a five point scale, recorded before stent insertion, the day after, and at least one month later at follow up. Technical success, early and late complications (perforation, migration, severe gastro-oesophageal reflux, haematemesis, and reobstruction due to tumour overgrowth) were also recorded.

RESULTS

In both stent groups, a significant improvement in dysphagia score was seen both the next day post stenting and at late follow up (p<0.05). No significant difference was seen in the improvement in dysphagia between the two groups (p>0.1). The frequency of complications encountered in the two groups was similar. Three patients in the Ultraflex group required two stents at primary stenting.

CONCLUSION

The two types of stent are equally effective in the palliation of dysphagia associated with lower third oesophageal malignancy and the complication rates associated with their use are comparable.

Results of urgent and emergency thoracic procedures treated by endoluminal repair

INTRODUCTION

emergency surgery on the thoracic aorta is associated with a high mortality. Endovascular treatment for these patients may offer a realistic alternative to open surgery.

METHOD

between 1997 and 2002 data was collected prospectively on all patients who underwent urgent or emergency endoluminal repair for thoracic aortic pathology. All patients had ruptured or were at risk of rupture, and had been assessed as high risk for open surgery.

RESULTS

twenty-four patients required urgent/emergency stent grafts. The median age was 74 (range 17-90). Indications included: trauma (transection in 3 and traumatic dissection in 1), acute symptomatic type B dissection (4), symptomatic degenerative aneurysms (7), false aneurysms associated with infection (6), Takayasu's vasculitis causing rupture of the descending thoracic aorta (1), symptomatic aneurysm associated with chronic dissection (1) and a secondary aorto-oesophageal fistula (1). The 30-day survival was 83.3% (20/24) and the survival at 1 year was 70.8% (17/24). The median follow-up was 13.5 months (range 2-57). The complications included: transient paraplegia (1), non-disabling stroke (1), distal endoleak treated with an extension cuff (1) and a proximal endoleak (1) which required removal of the graft at open surgery.

CONCLUSION

endoluminal repair of thoracic aortic disease requiring urgent/emergency treatment has encouraging results with low morbidity and mortality rates compared with open surgery. Long-term follow-up is required to assess the durability of the grafts.

Thoracic stent grafts

Background

The Endovascular Aneurysm Repair trial of infrarenal aortic aneurysm repair requires 20 operations to be performed at each centre to eliminate learning curve errors. An analysis was undertaken of the authors' learning curve experience of commercially made thoracic stent grafts.

Methods

Stent grafting was attempted in 26 patients. Aortic pathology included 13 atheromatous aneurysms, six dissections, one coarctation, three false aneurysms and three transections. Successful deployment was performed in 24 patients (92 per cent), but failed in two women due to small iliac arteries. Stent grafts used were Gore Excluder (16 patients), AneuRx (six), Vanguard (one) and Stenford (one). Four patients required two stents, two needed three stents, and 18 had a single stent.

Results

Thirteen elective procedures were uneventful. Two deaths occurred in 11 urgent procedures, from pulmonary embolism and aortic rupture of an unsuspected false aneurysm. The overall in-hospital mortality rate was 8 per cent (two of 24 patients). One graft with a persistent endoleak was removed at open repair at 6 weeks. The subclavian artery origin was covered in three elderly patients, resulting in minor distal ischaemia. No spinal cord problems were seen. One patient died from pneumonia at 8 weeks, and another died from rupture at 28 months as a result of prolapse of the stent into the aneurysm sac.

Conclusion

Assessment of the diameter of the iliac arteries is important, especially in women, to ensure that they accommodate the size of the sheath. Patients with false aneurysms have a poor outcome, and treatment by stent grafting may not be durable. Covering the origin of the left subclavian artery can be undertaken in elderly patients with transient minor symptoms. The use of stent grafts in acute type B dissection should be the subject of a randomized trial. Continued surveillance is essential.

Treatment of superior vena cava obstruction secondary to pacemaker wires with balloon venoplasty and insertion of metallic stents

AIMS

Pacemaker wires can result in stenosis of the superior vena cava and other central veins. The aim of this study is to demonstrate the safety and effectiveness of treating stenoses of the superior vena cava (SVC) and central veins with balloon venoplasty and metallic stent insertion in the presence of cardiac pacemaker wires.

METHODS AND RESULTS

Three patients were referred to the department after developing symptomatic SVC obstruction following implantation of a cardiac pacemaker several years earlier. They were examined with duplex ultrasound and venography, which revealed significant stenoses of the central veins. These patients subsequently underwent endovascular treatment which involved balloon dilation and stent insertion. The treatment was successful in all three patients, without any complications. Long-term patency of up to 4 years is recorded. No pacemaker function dysfunction was encountered.

CONCLUSION

SVC stenting is safe and effective in patients who develop the SVC obstruction after cardiac pacemaker insertion.