Mid-term Results of Coil Embolization Alone and Stent-assisted Coil Embolization for Renal Artery Aneurysms

Enhancing procedural decision making with cone beam CT in renal artery embolization

Cone-beam computed tomography (CBCT) has proven to be a safe and effective adjunctive imaging tool for interventional radiology. Nevertheless, limited studies have examined the application of CBCT in renal artery embolization (RAE). The objective of this study is to evaluate the role of CBCT in intra-procedural decision-making for RAE. This multicenter retrospective study included 40 consecutive patients (age: 55.9 ± 16.5 years; male, 55%) who underwent CBCT during RAE from January 2019 to January 2023. The additional information provided by CBCT was classified into Category 1 (no additional information), Category 2 (more information without changing the treatment plan), and Category 3 (valuable information that led to a change in the treatment plan). CBCT did not add unique information for four patients (10%) classified as Category 1. CBCT clarified ambiguous angiographic findings and confirmed the existing treatment plan for 19 patients (47.5%) graded as Category 2; complex vascular anatomy was explained (n = 13), and a correlation between vascular territory and target lesion was established (n = 6). CBCT offered valuable information that was not visible on digital subtraction angiography and changed the treatment plan for 17 patients categorized as Category 3; a mismatch between the vascular territory and the target lesion led to the identification of alternative (n = 3) and additional feeders (n = 8); and the extent of embolization was reduced by using automatic feeder detection software (n = 6). CBCT is an efficient tool that aids in the decision-making process during the embolization procedure by providing supplementary imaging information. This additional information enables the confident identification of target vessels, facilitates superselective embolization, prevents non-target embolization, and helps locate missing feeders.

A Qualitative Systematic Review of Endovascular Management of Renal Artery Aneurysms

PURPOSE

To perform a qualitative systematic review of endovascular management of renal artery aneurysms (RAAs).

MATERIALS AND METHODS

A comprehensive electronic search of PubMed, MEDLINE, Embase, Google Scholar, and Cochrane databases from 2000 to 2022 was performed using the search terms "renal artery," "aneurysm," and "endovascular." Means of outcome measures were calculated with a primary end point focused on RAA-related mortality and rupture. Secondary end points included reintervention rate and renal infarction.

RESULTS

Twenty-six, single-center, retrospective, observational studies were included. There were 454 RAAs treated in 427 patients using endovascular techniques. Mean age was 53.8 years, with a female predominance (62%). A variety of endovascular treatments of RAA were used with excellent technical success (96%), renal parenchymal preservation, and a low rate of moderate/severe adverse events (AEs). Primary coil embolization was the most commonly used technique (44.7%). There was an overall AE rate of 22.9%, of which 6.7% were moderate/severe and there was 0% periprocedural mortality. The most common AE was renal infarction (49 patients, 11.5%); however, renal function was preserved in 84% of patients. Nephrectomy rate was 0.4%. Computed tomography (CT) angiography was the most common imaging follow-up modality used in 72% of studies. Only 9 studies (34%) reported anticoagulant use. Although the risk of delayed aneurysm reperfusion warrants clinical and imaging surveillance, relatively few patients (3%) required reintervention in this cohort.

CONCLUSIONS

Endovascular management of RAA is a technically feasible treatment option with low rates of AEs and reintervention. The present study highlights the techniques available for interventional radiologists, a need for standardization of AE reporting, anticoagulation therapy, and follow-up imaging.

Endovascular Strategies and Outcomes for Aberrant Splenic Artery Aneurysms

OBJECTIVES

Aberrant splenic artery aneurysms (ASAAs) located at the splenomesenteric trunk (SMT) and the celiacomesenteric trunk have a close anatomical relationship with the superior mesenteric artery (SMA). The aim of this study was to review our institutional experience of endovascular treatment for ASAAs and evaluate the long-term outcomes.

METHODS

A retrospective review of patients with ASAAs who underwent endovascular treatment between December 2006 and December 2022 was performed. The demographics of the patients, aneurysm characteristics, treatment strategies, perioperative and long-term outcomes, and complications were analyzed.

RESULTS

A total of 29 patients with ASAAs were endovascularly treated at our institution. The SMT variant occurred in the majority of the patients. All ASAAs were characterized by eccentric growth and extremely short inflow arteries. Only 1 patient's inflow artery of the aneurysm exceeded 1 cm in length. Thirteen patients were treated by coil embolization alone. Four patients received bare stent-assisted coil embolization. A combination of coil embolization and covered stent placement across the orifice of the aberrant splenic artery was performed in the remaining 12 cases. Coil migration into the SMA occurred in 2 patients during the operation. Technical success was achieved in all patients. With a median duration of 63 (34-101) months of follow-up, no intestinal ischemia, aneurysm-related death, aneurysm rupture, or sac enlargement occurred. Three cases of aneurysm sac reperfusion were observed, and 1 patient underwent reintervention with secondary embolization. Asymptomatic occlusion of the covered stent was detected in 1 patient at 2 years.

CONCLUSIONS

Endovascular treatment is a safe, effective, and durable option for ASAAs. Inflow embolization might be difficult to achieve in ASAAs and poses a high risk of coil migration into the SMA. Long-term observation indicates that reasonable use of the covered stent could achieve reliable inflow artery exclusion in ASAAs without intestinal complications.

CLINICAL IMPACT

Aberrant splenic artery aneurysm (ASAA) is an extremely rare entity. This study reported a large sample size of ASAAs treated by endovascular techniques with long-term follow-up. The ASAA was characterized by an extremely short inflow artery and a close anatomical relationship with the superior mesenteric artery (SMA). Endovascular treatment is a safe, effective, and durable option for ASAAs. Inflow embolization might be difficult to achieve in ASAAs and pose a high risk of coil migration into the SMA. Long-term observation indicates that reasonable use of the covered stent could achieve reliable inflow artery exclusion in ASAAs without intestinal complications.

CIRSE Standards of Practice for the Endovascular Treatment of Visceral and Renal Artery Aneurysms and Pseudoaneurysms

BACKGROUND

Endovascular treatment of visceral and renal artery aneurysms and pseudoaneurysms is an effective, minimally invasive treatment that has been successfully used since the early 1990s, with refined and expanded techniques and tools currently offering excellent outcomes. Due to increased detection of such lesions in recent years, many of which are asymptomatic, revision of the indications for intervention and the correct endovascular treatment approaches has become essential.

PURPOSE

This document will presume that the indication for treatment is clear and approved by the multidisciplinary team and will define the standards required for the performance of each intervention, as well as their relative advantages and limitations. CIRSE Standards of Practice documents are not intended to impose a standard of clinical patient care, but recommend a reasonable approach to, and best practices for, the performance of the endovascular treatment of visceral and renal artery aneurysms and pseudoaneurysms.

METHODS

The writing group was established by the CIRSE Standards of Practice Committee and consisted of five clinicians with internationally recognised expertise in endovascular treatments. The writing group reviewed the existing literature on visceral and renal artery aneurysms and pseudoaneurysms, performing an evidence search using PubMed to identify publications in English and relating to human subjects from 1990 to 2022. The final recommendations were formulated through consensus.

RESULTS

Endovascular treatment has an established role in the successful management of visceral and renal artery aneurysms and pseudoaneurysms, and this Standards of Practice document provides up-to-date recommendations for its safe performance.

Visceral Artery Aneurysms Embolization and Other Interventional Options: State of the Art and New Perspectives

Visceral artery aneurysms (VAAs) are rare, usually asymptomatic and incidentally discovered during a routine radiological examination. Shared guidelines suggest their treatment in the following conditions: VAAs with diameter larger than 2 cm, or 3 times exceeding the target artery; VAAs with a progressive growth of at least 0.5 cm per year; symptomatic or ruptured VAAs. Endovascular treatment, less burdened by morbidity and mortality than surgery, is generally the preferred option. Selection of the best strategy depends on the visceral artery involved, aneurysm characteristics, the clinical scenario and the operator's experience. Tortuosity of VAAs almost always makes embolization the only technically feasible option. The present narrative review reports state of the art and new perspectives on the main endovascular and other interventional options in the treatment of VAAs. Embolization techniques and materials, use of covered and flow-diverting stents and percutaneous approaches are accurately analyzed based on the current literature. Visceral artery-related considerations and targeted approaches are also provided and discussed.