Rectal Venous Malformation Treated by Superior Rectal Artery Embolization.

A 25-year-old female was referred to the Interventional Radiology Department for investigation and treatment of a rectal venous malformation (RVM) causing large recurrent episodes of rectal bleeding and chronic anaemia. Magnetic resonance imaging (MRI) demonstrated a large venous malformation affecting the rectum, lower pelvis and left thigh. After three failed attempts at injection foam sclerotherapy using fluoroscopic colonoscopy, a multidisciplinary team proposed an embolization procedure of the arterial inflow to the venous malformation. Following discussion with the patient, embolization of the superior rectal arteries was undertaken with immediate on-table fluoroscopic improvement in the RVM. Post-treatment, a significant reduction in bleeding, was reported by day 10 with subsequent return to activities of daily living and full employment. Follow-up MRI at 1 year demonstrated significant reduction in bowel-wall thickening.

Technical and Clinical Outcomes Following Colonic Stenting: A Seven-Year Analysis of 268 Procedures.

AIMS: To assess the factors contributing to the technical and clinical success of colorectal stenting for large bowel obstruction. METHODOLOGY: 268 cases of colonic stenting for large bowel obstruction were performed in 249 patients of mean age of 72 years (28-98) between 2006 and 2013. The majority of strictures were due to malignant disease, 244/268 (91 %). Diverticular strictures accounted for 24/268 (9 %). RESULTS: Overall technical success rate was 81 % (217/268), with a clinical success rate of 65 % (174/268). Duration of symptoms ranged from 0 to 180 days (mean 8 days). Technical success rate was seen to decrease with increasing symptom duration. For symptom duration of less than 1 week, technical success was 85.4 % (181/212) versus 69.6 % (39/56) for those with symptoms of greater than a week (p < 0.05). Clinical success rates fell from 71.3 % (107/150) to 59.3 % (70/118) (p < 0.05) when attempting to stent lesions of greater than 5 cm. There was also a significant reduction in clinical success when stenting lesions on a bend rather than a straight segment of colon 75.7 % (109/144) versus 59.7 % (74/124) (p < 0.05). A total of 20 (7.46 %) perforations were identified during the study. Stent migration occurred in 6.6 % of cases. In-stent stenosis occurred in 3.3 %. The overall 30-day all cause mortality rate was 9 %. CONCLUSION: Lesion size, location and duration of obstructive symptoms are statistically significant determinants of patient outcome. These factors could be used to advise patient selection for colonic stenting or direct progression to surgical intervention.

Radiology and mesenteric ischaemia.

This review focuses on the radiology of mesenteric ischaemia. Covering the acute and chronic presentations, both of which result from impaired vascularisation of the gastrointestinal tract, we evaluate the role of radiographs, ultrasound, CT, MRI, and catheter angiography in the diagnosis of these conditions. Looking to the future, we also assess some of the emerging imaging techniques. Across medicine and surgery there has been a significant shift towards minimally invasive interventions. Although percutaneous revascularisation of chronic mesenteric ischaemia has been performed for some time, there has been a developing trend for the use of such techniques in acute mesenteric ischaemia. We evaluate the available evidence for the use of these percutaneous interventions and assess how they compare with or in some instances compliment traditional surgical alternatives.

Antibiotics in interventional radiology.

The range and number of interventional procedures is rapidly increasing each year. A major complication associated with many procedures is infection, which can result in serious adverse outcomes for the patient. Consequently, antibiotics are amongst the most common pharmaceuticals used by the interventionist, particularly for non-vascular procedures, yet almost no randomized controlled trial data exist to inform our decision when formulating appropriate antibiotic prophylaxis regimens. The purpose of this review is to provide an update on the utilization of antibiotics for common interventional radiology procedures, focusing on timing and duration of antibiotic prophylaxis.

Modelling the influence of endothelial heterogeneity on the progression of arterial disease: application to abdominal aortic aneurysm evolution.

We sophisticate a fluid-solid growth computational framework for modelling aneurysm evolution. A realistic structural model of the arterial wall is integrated into a patient-specific geometry of the vasculature. This enables physiologically representative distributions of haemodynamic stimuli, obtained from a rigid-wall computational fluid dynamics analysis, to be linked to growth and remodelling algorithms. Additionally, a quasistatic structural analysis quantifies the cyclic deformation of the arterial wall so that collagen growth and remodelling can be explicitly linked to the cyclic deformation of vascular cells. To simulate aneurysm evolution, degradation of elastin is driven by reductions in wall shear stress (WSS) below homeostatic thresholds. Given that the endothelium exhibits spatial and temporal heterogeneity, we propose a novel approach to define the homeostatic WSS thresholds: We allow them to be spatially and temporally heterogeneous. We illustrate the application of this novel fluid-solid growth framework to model abdominal aortic aneurysm (AAA) evolution and to examine how the influence of the definition of the WSS homeostatic threshold influences AAA progression. We conclude that improved understanding and modelling of the endothelial heterogeneity is important for modelling aneurysm evolution and, more generally, other vascular diseases where haemodynamic stimuli play an important role.

Percutaneous cholecystostomy: the radiologist's role in treating acute cholecystitis.

Acute cholecystitis is a common condition, with laparoscopic cholecystectomy considered the gold-standard for surgical management. However, surgical options are often unfavourable in patients who are very unwell, or have numerous medical co-morbidities, in which the mortality rates are significant. Percutaneous cholecystostomy (PC) is an image-guided intervention, used to decompress the gallbladder, reducing patient's symptoms and the systemic inflammatory response. PC has been shown to be beneficial in high-risk patient groups, predominantly as a bridging therapy; allowing safer elective cholecystectomy once the patient has recovered from the acute illness; or, in the minority, as a definitive treatment in patients deemed unfit for surgery. This review aims to develop a broader understanding of PC, discussing its specific indications, patient management, technical factors, imaging guidance, and outcomes following the procedure.

Prospective study evaluating technical and clinical outcomes from the use of low profile angioplasty (LOPA) systems.

AIM: To compare the success and complication associated with 4 and 5 F access systems prospectively in the treatment of infra-inguinal vascular disease. MATERIALS AND METHODS: One hundred and twenty consecutive patients were treated for lower limb vascular disease via a 4 F (n = 60) or 5 F (n = 60) access sheath over a 12 month period. All common femoral arteries were punctured in an antegrade direction with ultrasound guidance. Seven minutes of manual compression was applied and the groin assessed with ultrasound to document complications. Repeated manual compression was applied until haemostasis was achieved in all cases. Time to haemostasis, equipment used, patient biochemical data, and demographics were recorded. Patients were followed-up at a mean of 12 weeks post-procedure. RESULTS: Antegrade access and sheath insertion was achieved in all cases. The technical success of the procedure was 56/60 (93%) cases using 4 F access and 57 (95%) cases using 5 F access. The time to haemostasis was reduced to a mean of 8.2 min (range 7-12 min) with a 4 F system compared to a mean of 12 min (range 7-30 minutes) with a 5 F system (p = 0.045). Overall there were 12 complications (10%; 11 <2 cm haematomas and one pseudoaneurysm) noted on ultrasound post-haemostasis, although there was no statistically significance difference between the two groups. Hypertension and renal dysfunction were associated with complications (p < 0.05). A 4 F system used an additional average of 5.1 (range 3-8) wires and catheters compared to an additional average of 3.5 (range 2-6) wires and catheters when using a 5 F system (p = 0.002). A 4 F technique cost three-times that of a 5 F technique. CONCLUSION: Four and 5 F access sheaths allow safe and successful infra-inguinal angioplasty with a low complication rate. Hypertensive patients and those with impaired renal function are at increased risk of complications. There are increasing costs using a 4 F system offset by a decrease in time to haemostasis following manual compression but no reduction in complication rate.

The role of interventional radiology and imaging in pancreatic islet cell transplantation.

Pancreatic islet cell transplantation (PICT) is a novel treatment for patients with insulin-dependent diabetes who have inadequate glycaemic control or hypoglycaemic unawareness, and who suffer from the microvascular/macrovascular complications of diabetes despite aggressive medical management. Islet transplantation primarily aims to improve the quality of life for type 1 diabetic patients by achieving insulin independence, preventing hypoglycaemic episodes, and reversing hypoglycaemic unawareness. The islet cells for transplantation are extracted and purified from the pancreas of brain-stem dead, heart-beating donors. They are infused into the recipient's portal vein, where they engraft into the liver to release insulin in order to restore euglycaemia. Initial strategies using surgical access to the portal vein have been superseded by percutaneous access using interventional radiology techniques, which are relatively straightforward to perform. It is important to be vigilant during the procedure in order to prevent major complications, such as haemorrhage, which can be potentially life-threatening. In this article we review the history of islet cell transplantation, present an illustrated review of our experience with islet cell transplantation by describing the role of imaging and interventional radiology, and discuss current research into imaging techniques for monitoring graft function.

Successful recanalization of a longstanding right common iliac artery occlusion with a radiofrequency guidewire.

We describe a case of successful recanalization of a longstanding right common iliac occlusion with a radiofrequency (RF) guidewire. The patient had been symptomatic with claudication for 3 years, and a preliminary attempt to cross the lesion using conventional techniques proved unsuccessful. Using low and medium intensity RF pulses and a PowerWire, a tract through the occlusion was established, which allowed subsequent stenting with an excellent angiographic result and a good immediate clinical response. We propose this as a useful technique in the peripheral arterial system for occlusive lesions not amenable to traditional recanalization techniques.

Uterine artery embolisation for symptomatic adenomyosis--mid-term results.

PURPOSE: To evaluate the role of uterine artery embolisation (UAE) in the treatment of adenomyosis. MATERIALS AND METHODS: 27 women with symptomatic adenomyosis diagnosed on magnetic resonance imaging (MRI) underwent UAE between 1998 and 2004. Clinical evaluation using a standardised questionnaire was made at regular intervals after embolisation to assess patient outcome. RESULTS: The diagnosis of adenomyosis was confirmed histologically by transvaginal biopsy in 5 women. There were 14 women with associated uterine fibroids. Diffuse adenomyosis was identified in 18 women. A focal adenomyoma was present in another 8 women. In 1 patient adenomyosis was not classified. All patients except one underwent bilateral uterine artery embolisation. There was an initial favourable clinical response, with improvement of menorrhagia in 79% (13/16) of patients at 12 months. Follow-up data was available on a total of 14 patients at 2 and 3 years after embolisation. 45.5% (5/11) reported a deterioration in menorrhagia symptoms at 2 years. CONCLUSION: UAE for symptomatic adenomyosis is effective in the short-term but there is a high rate of recurrence of clinical symptoms 2 year following treatment.

Device-specific outcomes following endovascular aortic aneurysm repair.

OBJECTIVE: To compare aneurysm morphology, initial outcomes and mid-term results in patients receiving Talent or Zenith grafts for elective endovascular aneurysm repair (EVR). METHODS: Over a 6-year time period ending in 2007, 286 patients underwent elective EVR of infra-renal abdominal aortic aneurysms using Talent or Zenith devices. Patient demographics, aneurysm morphology and initial outcomes (primary-assisted technical success rates, 30-day limb occlusion, re-intervention and mortality) were compared using chi-squared tests or Student's t-tests. Kaplan-Meier curves were calculated to compare cumulative rates of freedom from type I or III endoleak, re-intervention, endograft patency and overall survival over mid-term follow-up. RESULTS: Adverse aneurysm morphology was more common in patients receiving Zenith stent grafts, with a greater proportion of shorter neck lengths (<10mm, 12.9% vs 0%; p60 degrees , 25.0% vs 10.3%; p=0.002). Equivalent primary-assisted technical success rates were achieved with both Talent and Zenith grafts (94.0% vs 96.1%; p=0.41). A significant number of adjunctive procedures were required in both groups to obtain a proximal endograft seal, with relatively more procedures performed in the Talent group (28.6% vs 12.4%; p=0.003). Early outcomes were similar for 30-day re-intervention (5.3% vs 3.9%; p=0.91), 30-day limb occlusion (1.5% vs 2.6%; p=0.51), 30-day morbidity (6.8% vs 11.8%; p=0.15) and 30-day mortality (4.5% vs 3.9%; p=0.80). The cumulative incidence of freedom from re-intervention was 88.3+/-2.9%, 86.1+/-3.3% and 84.1+/-3.9% at 1, 2 and 3 years respectively. There were no significant differences between Talent and Zenith groups for re-intervention, type I or III endoleak or limb occlusion rates over the same time period. Overall patient survival was 88.4+/-2.85% at 1 year, 83.7+/-4.0% at 2 years and 78.9+/-5.5% at 3 years. CONCLUSIONS: Equivalent primary-assisted technical success rates can be achieved using either Talent or Zenith endografts for endovascular aneurysm repair, but operating teams should be prepared to perform additional adjunctive procedures to obtain a primary proximal seal with either stent. The Zenith endograft performed well in the context of less favourable pre-operative aneurysm morphology. Both Talent and Zenith endografts appeared equally durable in the medium term.

Aortic morphology following endovascular repair of acute and chronic type B aortic dissection: implications for management.

OBJECTIVE: The study aimed to define early clinical outcomes, and medium term morphological changes, following endovascular treatment of acute (AAD) and chronic (CAD) Type B aortic dissections. MAIN OUTCOMES: The cohort comprised 78 patients who underwent endovascular repair for AAD (38) and CAD (40). Early and late clinical outcomes were prospectively recorded. All patients underwent serial follow up with CT scanning. False lumen thrombosis rates, true, false and total aortic short axis diameter were recorded at the mid point of the endograft and below this level in the thoracic aorta. The total maximum aortic diameter in the thoracic, abdominal aorta was quantified. RESULTS: The 30-d mortality was 2.6% in AAD and 7.5% in CAD. The 30-d stroke and paraplegia rates were 5.3% and 0% in AAD. There were no cases of stroke or paraplegia in patients with CAD. At 30 months follow up, the cumulative survival for the two groups was 93% for AAD and 66.5% for CAD (P=0.015, Kaplan Meier) and the cumulative re-intervention rate was 62% and 55% in AAD and CAD respectively (P=0.961, Kaplan-Meier). False lumen thrombosis rates were equivalent in the two groups and were higher at the level of the endograft than below this level (P<0.05). Aortic remodelling was greater in AAD, whereas the aortic dimensions after treatment of CAD remained relatively static. Up to 20% of patients in both groups demonstrated enlargement of the thoracic aorta. CONCLUSIONS: The data support the use of endovascular repair of the thoracic aorta in Type B aortic dissection. 30-d outcomes are acceptable. Patients with AAD demonstrate significant aortic remodelling whereas patients with CAD do not. This has significant implications for practice as patients with CAD must rely on maintenance of false lumen thrombosis to preserve the integrity of the endovascular repair.

Radiological treatment of symptomatic uterine fibroids.

Uterine artery embolization (UAE) is a relatively new alternative treatment for symptomatic fibroids. Recent Level 1 evidence from two major randomized controlled trials has established UAE as a safe and effective alternative to hysterectomy. Technical aspects, choice of embolic agent, safety, contra-indications and complications of the procedure will be reviewed. The available data on the effects on ovarian function, fertility and pregnancy outcomes following UAE will be presented.

Outcomes after unilateral uterine artery embolization: a retrospective review.

PURPOSE: Bilateral uterine artery embolization (UAE) is considered necessary to provide effective treatment for symptomatic uterine fibroids. Occasionally, only unilateral embolization is performed, and this study evaluates these outcomes. MATERIALS AND METHODS: As part of a prospective observational study of more than 1600 patients treated with UAE since 1996, there have been 48 patients in whom unilateral embolization has been performed. This study retrospectively reviews clinical response as assessed by our standard questionnaire and radiological response assessed by either magnetic resonance imaging or ultrasound. RESULTS: Two principal groups emerged: the largest, where only the dominant unilateral arterial supply was electively embolized (30 patients); and the second, where there was technical failure to catheterize the second uterine artery as a result of anatomical constraints (12 patients). Favorable clinical response with a reduction in menorrhagia at 1 year was seen in 85.7% (18/21) of those patients with a dominant arterial supply to the fibroid(s). In contrast, in those patients where there was technical failure to embolize one uterine artery, there was a high rate of clinical failure requiring further intervention in 58.3% (7/12). Comparison of the technical failure group with the dominant uterine artery group demonstrated a statistically significant (Fisher's exact test) difference in the proportion of patients with evidence of persistent fibroid vascularity (p < 0.001) and requiring repeat intervention (p < 0.01). CONCLUSION: We conclude that unilateral UAE can achieve a positive clinical result in the group of patients where there is a dominant unilateral artery supplying the fibroid(s), in contrast to the poor results seen following technical failure.

How safe is bilateral internal iliac artery embolization prior to EVAR?

PURPOSE: To assess the outcomes of patients after bilateral internal iliac artery (IIA) embolization prior to endovascular aneurysm repair (EVAR). METHODS: Thirty-nine patients (age range 55-88 years, mean 72.5 years; 2 women) underwent IIA embolization/occlusion before EVAR. There were 28 patients with aorto-biiliac aneurysms and 6 with bilateral common iliac artery (CIA) aneurysms. Five patients with unilateral CIA aneurysms had previous surgical ligation of the contralateral IIA or inadvertent covering by the stent-graft of the contralateral IIA origin. Outcomes were assessed by clinical follow-up. RESULTS: Severe ischemic complications were limited to spinal cord ischemia in 1 patient (3%) who developed paraparesis following EVAR. No other severe ischemic complications such as buttock necrosis, or bowel or bladder ischemia, occurred. Buttock and/or thigh claudication occurred in 12 patients (31%) and persisted beyond 1 year in 3 patients (9%). Sexual dysfunction occurred in 2 patients (5%). Patients who underwent simultaneous embolization had a 25% (3/12) ischemic complication rate versus 41% (11/27) in those with sequential embolization (p = 0.48). Embolization limited to the main trunk of the IIA resulted in a significantly reduced ischemic complication rate of 16% (3/19) versus 55% (11/20) of patients who had a more distal embolization of the IIA (p = 0.019, Fisher's exact test). CONCLUSION: Severe complications after bilateral IIA embolization are uncommon. Although buttock/thigh claudication occurs in around 30% of patients soon after the procedure, this resolves in the majority after 1 year. There is no obvious benefit for sequential versus simultaneous IIA embolization in our series. Occlusion of the proximal IIA trunk is associated with reduced complications compared with occlusion of the distal IIA.

Prospective study of elective bilateral versus unilateral femoral arterial puncture for uterine artery embolization.

The purpose of this study was to assess the effect of elective bilateral femoral arterial punctures for uterine artery embolization (UAE) of symptomatic fibroids on fluoroscopy and procedural time, patient dose, and ease of procedure. We conducted a prospective study of UAE with either the intention to catheterize both uterine arteries using a single femoral puncture (n = 12) or elective bilateral arterial punctures from the outset (n = 12). The same two operators undertook each case. Main outcome measures were total procedure time, fluoroscopy time, dose-area product (DAP), and total skin dose. A simulation was then performed on an anthropomorphic phantom using the mean in vivo fluoroscopy parameters to estimate the ovarian dose. Bilateral UAE was achieved in all patients. None of the patients with initial unilateral arterial puncture required further contralateral arterial puncture. The mean fluoroscopy time in the group with elective bilateral punctures was 12.8 min, compared with a mean of 16.6 min in patients with unilateral puncture (p = 0.046). There was no significant difference in overall procedure time (p = 0.68). No puncture-site complications were found. Additional catheters were required only following unilateral puncture. The simulated dose was 25% higher with unilateral puncture. Although there was no significant difference in measured in vivo patient dose between the two groups (DAP, p = 0.32), this is likely to reflect the wide variation in other patient characteristics. Allowing for the small study size, our results show that the use of elective bilateral arterial punctures reduces fluoroscopy time, requires less catheter manipulation, and, according to the simulation model, has the potential to reduce patient dose. The overall procedure time, however, is not significantly reduced.

Radiological insertion and management of peritoneovenous shunt.

The purpose of the study was to report our experience of the management of complications following the insertion of a peritoneovenous shunt for intractable malignant ascites. From June 1999 to January 2006, 26 patients underwent insertion of a peritoneovenous shunt for ascites by interventional radiologists. We have used ultrasound and shuntography to assist in the diagnosis of the cause of shunt blockage. Successful techniques for the restoration of the shunt function include port- pumping, stripping of any fibrin sheath, and revision of either the venous or peritoneal catheter. The procedure was initially successful in all patients with continued patency until death in 17. A further four patients are still alive with a functioning shunt. There was one rapid postprocedure death resulting from pulmonary edema. Two patients developed pneumothorax, managed successfully with either a chest drain or aspiration. Shunt dysfunction occurred eight times in seven patients. There were five successful revisions in four patients. Overall, shunt patency has been maintained in 80.1% of patients. Shunt dysfunction is seen in a significant number of patients, but successful revision of the shunt can be achieved in the majority.

Endovascular embolization of visceral artery aneurysms with ethylene-vinyl alcohol (Onyx): a case series.

We report the application of the liquid embolic agent ethylene-vinyl alcohol (Onyx; MicroTherapeutics, Irvine, CA, USA) in the management of visceral artery aneurysms. The technique and indications for using Onyx are discussed with emphasis on the management of wide-necked aneurysms and maintenance of patency of the parent vessel. None of the cases was considered suitable for stent-grafting or embolization with conventional agents. Two aneurysms of the renal artery bifurcation and one aneurysm of the inferior pancreaticoduodenal artery were treated. Following treatment there was complete exclusion of all aneurysms. There was no evidence of end-organ infarction. Follow-up with intervals up to 6 months has shown sustained aneurysm exclusion. Onyx is known to be effective in the management of intracranial aneurysms. Our experience demonstrates the efficacy and applicability of the use of Onyx in the treatment of complex visceral artery aneurysms.