Unusual Intracranial Manifestation of Infective Endocarditis

Objective: The mycotic aneurysm is a rare intracranial pathology seen with pre-existing infective endocarditis. It has a high mortality rate due to its risk of rupture and needs early diagnosis and treatment. Methods: A 23-year male patient who presented with infective endocarditis subsequently developed a left parietal-temporal intracranial haemorrhage with suspicion of aneurysm after the course of antibiotic treatment as seen on Computed Tomography (CT) scan. Digital Subtraction Angiography (DSA) revealed a ruptured fusosaccular aneurysm in the distal parietal branches of the left Middle Cerebral Artery (MCA), for which glue embolization of the distal parent artery and aneurysm was done. Result: The interventional endovascular procedure was done with complete obliteration of the distal parent artery, mycotic aneurysm, and normal filling of the left internal cerebral artery (ICA) branches. Conclusion: Mycotic intracranial aneurysms (MIA) are a rare form of cerebrovascular pathology which needs early diagnosis with endovascular intervention when rupture occurs.

Percutaneous Translymphocele Embolization of Retroperitoneal Lymphatic Leak

Iodized oil-based lymphangiography (LAG) is a well-established diagnostic exam during the workup of postoperative lymphatic leaks. Computed tomography (CT) has been shown to be a useful complement to optimize treatment planning and can easily be performed after conventional LAG. The treatment options for lymphatic leaks include conservative dietary modification, sclerotherapy, embolization, and surgery. We present a case of a 48-year-old man who developed a symptomatic left retroperitoneal lymphatic fluid collection after left nephrectomy, complicated by postoperative retroperitoneal abscess. Retroperitoneal duct leak was confirmed via ultrasound-guided intranodal LAG and post-LAG CT. This leak was successfully managed with N-butyl cyanoacrylate glue embolization of the leaking lymphatics via fluoroscopic-guided catheterization of the leak via percutaneous access through the lymphatic fluid collection.

Abstract 1122‐000052: Endovascular Management of Infectious PICA Aneurysm in the Setting of Recent Dental Work

Introduction : Infectious intracranial aneurysms (IIA) of the posterior inferior cerebellar artery (PICA) are exceedingly rare and have been infrequently reported. IIAs are typically distal and located in the anterior circulation, particularly the middle cerebral artery and its distal branches. Etiology is secondary to hematogenous spread of septic emboli from a proximal source such as infective endocarditis. Few cases have documented an association between IIA and dental disease or procedures. We describe a rare case of an infectious PICA aneurysm in the setting of recent dental work and successfully treated with endovascular intervention. Methods : An 88‐year‐old male with medical history of atrial fibrillation on anticoagulation presented with one month duration of recurrent falls and progressive generalized weakness. CT head demonstrated left cerebral hemorrhage with scattered subarachnoid hemorrhage. MRI brain noted a rounded enhancing intra‐axial lesion located at the left paramedian cerebellum measuring 7 mm in maximal dimension. Further investigation with cerebral angiography demonstrated an infectious intracranial aneurysm of the left PICA. He underwent workup with an echocardiogram that noted a mobile echo density on the aortic valve consistent with a vegetation. Blood cultures were positive for Streptococcus salivarius and viridans. Investigation revealed that he had recent dental work performed and missed taking his prophylactic amoxicillin. Infectious disease was consulted and etiology was determined to be seeding of aortic valve from recent dental procedure that ultimately led to IIA formation. Results : Patient was treated with 6‐week course of intravenous ceftriaxone and underwent glue embolization for his left PICA aneurysm. Post embolization angiogram did not reveal any evidence of contrast filling within the aneurysm. He tolerated the procedure well with no complications and was subsequently discharged to inpatient rehabilitation with a modified Rankin scale (mRS) score of 3. Conclusions : IIAs of PICA in the setting of recent dental procedures are exceptionally rare and challenging to diagnose. They may be clinically silent until rupture and are usually identified incidentally on imaging or during autopsy. Physicians should maintain vigilance for this unique entity as prompt recognition and timely intervention may prevent severe morbidity and mortality.

Abstract 1122‐000064: Modern Brain Arteriovenous Malformation Models

Introduction : Research of William Hunter’s hypothesized (then discovered) arteriovenous varix (now arteriovenous malformation/AVM) has developed exponentially over the previous quarter‐millennium. 1 Virchow and Luschka’s subsequent contributions (nearly 100 years later) by identifying an AVM of the brain and its congenital nature were two of the first significant developments made in the field. 2,3 AVMs present as an erroneous connection (known as a fistula) between an artery and a vein that bypasses the capillary circulation. 4 The arteries and arterioles contributing to the malformation are known as feeders which connect to the draining veins via a plexiform vascular network known as a nidus. Prior to the design of a synthetic anastomosis coupled with vessel ligation by Spetzler et al, animal models were largely based on embolization or study of the normal anatomy. The animal and early genetic models have been reported on at length and numerous times across the literature, but novel developments spanning the previous decade have ushered in a technological revolution of vascular modeling that warrants discussion and analysis. Methods : Parameterization of a PubMed query to include all literature including the words “brain,” “arteriovenous malformation,” and “model,” yielded 489 articles. Results : After extraction of relevant literature and full‐text screening, 41 articles were chosen for detailed review. Conclusions : While centuries of treatment efforts have progressed from reliance on surgical resection to endovascular approaches (E.g. glue embolization or coiling) and stereotactic radiosurgery (SRS), it was only 43 years ago that the pathology was first modeled in the laboratory. 6 AVM modeling began with an outgrowth of highly specialized, yet not standardized, simulations of feline, canine, murine, primate, swine, ovine, and even leporine origin. These models were motivated by advancements in microsurgical techniques that permitted their creation, development of new technologies to investigate within them, and theories that these AVM representations could support or refute. The first functional model of AVM by anastomosis of the left rostral CCA and caudal JV was developed to study normal perfusion pressure breakthrough theory: its configuration is still employed by animal AVM models in the modern day (though largely in sheep and pigs). The elegance of the CCA‐JV fistula became a component of the now oft‐used RM AVM model which relies on retrograde flow through the RMs via CCA‐JV anastomosis. Similarly, the use of this functional AVM animal model has informed the molecular underpinnings of such lesions as well. Technological innovations outside of neurosurgery have greatly impacted the development of novel AVM models in the form of three‐dimensional flow models printed into silicon models and combined with advanced imaging technology such as 4D flow MRI. Technological developments in preservation solutions, catheterization tools, and imaging technologies have also allowed for advent of the cerebrovascular placental model for testing of treatments such as radiosurgery, glue embolization, coiling, as well as histological assessment of tissue directly after intervention.

Percutaneous Lymphatic Maceration and Glue Embolization for High-output Chylous Ascites after Robot-assisted Laparoscopic Nephrectomy and Lymphadenectomy

To propose minimally invasive percutaneous techniques in the management of high output chylous ascites, a known potential complication of retroperitoneal surgery associated with significant morbidity and mortality. Management has traditionally been based on successful treatment reported in the literature. However, refractory or high-output leaks often prove difficult to treat and there is little evidence on superior management. We report percutaneous maceration and embolization for the management of high-volume abdominal chyle leak after robot-assisted laparoscopic (RAL) radical nephrectomy and lymph node dissection for renal cell carcinoma. A 68-year-old male with incidentally found renal cell carcinoma underwent RAL radical nephrectomy with paraaortic lymph node dissection. He initially improved after surgery but developed significant abdominal pain and distension approximately 7 weeks postoperative. This proved to be chyloperitoneum. Conservative management was initiated, but after continued high-output (>1 L) fluid drainage, we pursued adjunct intervention involving Interventional Radiological percutaneous procedures. This included lymphatic maceration and glue embolization of leaking lymphatics. The patient tolerated the percutaneous procedures well with significant improvement in drain output ultimately leading to complete resolution of ascites without further complication. Similar interventions have previously been reported in the literature for cases of chylothorax with success. However, there is a lack of reports on utilizing this minimally invasive procedure for chyloperitoneum after retroperitoneal urologic surgery. We report our successful experience with percutaneous lymphatic maceration and embolization for high output chylous ascites after RAL radical nephrectomy with lymphadenectomy. We believe that early initiation utilizing these percutaneous techniques can achieve timely resolution and should be considered in the management of these patients.

N-Butyl Cyanoacrylate Embolization in Management of Iatrogenic Renal Hemorrhages—Single-Center Study Evaluating Safety and Efficacy

Objectives: The aim of the study was to evaluate the efficacy of endovascular N-butyl cyanoacrylate (NBCA)/glue embolization alone in the management of iatrogenic renal injuries and its effect on renal function. Methods: Thirty-one patients who presented with significant iatrogenic renal injuries over a time period ranging from June 2013 to June 2018 were evaluated. The clinical features, lab parameters, and imaging findings were recorded. The embolizing agent used was exclusively NBCA. The success rate was calculated along with the effect of glue embolization on kidney in the form of postembolization ischemia and change in the serum creatinine levels in immediate pre- and postembolization period. The time between the iatrogenic injury and angioembolization as well as the time from angioembolization to discharge was also calculated. Recurrence was evaluated at 1 and 6 months follow-up. Results: NBCA embolization showed 100% technical and clinical success in our study and no recurrence was noted at follow-up. Glue was also able to achieve complete embolization in patients with coagulopathy (n = 14, 45.1%). Percentage area deficit of normal renal blush in the postembolization check angiogram varied from 4 to 15.7% with a mean deficit of 7.65%. No significant difference in the serum creatinine was noted in immediate postembolization period. Conclusions: We conclude that glue is an effective embolizing agent for management of iatrogenic renal injuries even in coagulopathy patients with minimal area of parenchymal loss, no significant effect on renal functions, and no recurrence on 6 months follow-up.

The Minimally Invasive Treatment of Visceral Artery Pseudoaneurysms: A Retrospective Observational Single Centre Cohort Study on Glue Embolization

Objective The objective is to report a single centre experience in the embolization of visceral artery pseudoaneurysms with N-butyl-cyanoacrylate-methacryloxy sulfolane (NBCA-MS). Methods A retrospective observational cohort study was conducted on data about all consecutive patients treated for visceral artery pseudoaneurysms in the Interventional Radiology Unit of SS Annunziata Hospital, in Taranto (Italy) between January 2016 and July 2020. Only patients treated with NBCA-MS embolization were included. Clinical and technical outcomes were evaluated during in-hospital stay and at 3-month follow-up by computed angiotomography (CTA). Results Among 89 patients undergoing treatment for visceral artery pseudoaneurysm, a total of 58 (65.2%) patients (n = 32, 55.2% men; median age 45.8 years, range: 35–81) treated with NBCA-MS only were enrolled. Pseudoaneurysms were located in the renal artery (n = 18 cases, 31%), in the splenic artery (n = 27, 46.6%), in the intra-parenchymal hepatic artery (n = 3, 5.2%), in the common hepatic artery (n = 4, 6.9%) or in the pancreatic artery (n = 6, 10.3%). N-butyl-cyanoacrylate was diluted 1:1 with Lipiodol ultra-fluid, and mean volume injected was 0.6 ± 0.3 mL (range: 0.2–2.8 mL). Embolization was technically and clinically successful in all patients (n = 58, 100%) with an immediate total thrombosis of the pseudoaneurysm at the completion angiography. No systemic complications were noted in all cases. Five cases (8.6%) of non-target vessel embolization occurred without any clinical complication. No pseudoaneurysm recurrence was detected at the CTA control 1 day postoperatively. In one case (1.7%), a recurrence was detected 4 days after the initial treatment and successfully managed by a repeated NBCA-MS embolization. During the hospital stay, 56 patients recovered well but 2 (3.4%) died from multi-organ failure not related to the embolization. No recurrences were detected at the 3-month postoperative CTA in the remaining patients. Conclusions In properly selected patients affected with visceral artery pseudoaneurysms, NBCA-MS represents a definitive and safe embolization agent.