Infectious Intracranial Aneurysms Research Articles

Newly formed and ruptured infectious intracranial aneurysm in few days following first intracranial aneurysm embolization concurrent with middle cerebral artery occlusion: A regrettable case in a baby child

AbstractInfectious intracranial aneurysm (IIA) and embolic cerebral infarction are well‐known devastating complications of children suffering infective endocarditis. In this report, we describe a successfully embolized IIA concurrent with bilateral middle cerebral artery (MCA) occlusion. Unfortunately, a newly formed IIA located in the contralateral MCA bifurcation ruptured at the seventh day following embolization. A 6‐month‐old female child was admitted to hospital 3 days following acute right limb mobility disorder. An interventional surgery history of congenital heart disease was confirmed. She was immediately started on antibiotic therapy and the computed tomography agiography (CTA) scan showed occlusion of the upper branch of the left MCA. Unfortunately an IIA was located in the distal artery region (DAR) of the ipsilateral anterior cerebral artery. Angiography (digital subtraction angiography) was performed and the DAR IIA was embolized by OnyX‐18 with Magic 1.2 Fr. microcatheter. On the sixth day, magnetic resonance imaging during the hospital stay showed reduced infarction area with no other special sign. Desperately, a major seizure with opisthotonos attacked the baby on the seventh day after embolization. An immediate CTA scan showed massive hematoma in the right basal ganglia and a ruptured bifurcate aneurysm of the right MCA. The parents refused positive treatment and discharged in considering the critical situation. It should be noted that IIA can be fast formed anywhere in cerebral artery and dynamic angio‐image should be performed as supervision.

Abstract 147: Utilization and Application of Transcranial Doppler Emboli Monitoring for Infective Endocarditis

Introduction The rapid growth of the elderly population, an increase in cardiac disease, and notable use of intracardiac prosthetic devices has led to an increased prevalence of infective endocarditis (IE). Among the sequelae observed with an IE diagnosis, acute ischemic stroke (AIS), subarachnoid hemorrhage (SAH), intracerebral hemorrhage (ICH), vasculitis, septic emboli, cerebral abscess, and infectious intracranial aneurysms (IIA) continue to complicate overall management of this disease. Current literature on neurological complications of IE includes limited data on the defined role of neuroimaging in dictating inpatient management. Transcranial doppler (TCD) emboli monitoring with high intensity signals (HITS) offers a real time, radiation‐free, relatively low cost, non‐invasive imaging option to potentially risk stratify and identify candidates for earlier intervention to prevent further cerebrovascular (CV) complications. Methods We conducted an observational study of infective endocarditis cases admitted to our institution from April 2022 to May 2023 who had TCD with HITS completed. Baseline clinical characteristics (age, sex, date and timing of TCD with HITS study, date of last positive blood culture, organism of infection, other neuroimaging utilized) were recorded. Observations recorded included the results of the TCD with HITS studies, the overall incidence and timing of neurological complications (AIS, SAH, ICH, IIA, septic emboli, cerebral abscess), timing of valve surgery, and inpatient mortality rates. A positive HITS was defined as detection of cerebral microembolism during ultrasound monitoring of bilateral middle cerebral arteries (MCA) for 30 minutes using a TCD machine (VIASONIX Dolphin IQ). Results Between April 2022 to July 2023, we identified 22 patients with confirmed left‐sided infective endocarditis who underwent TCD with HITS. Mean age was 66 years (SD, 10), and 82% were men. Leading pathogen types were Enterococcus Faecalis (27%) and Staphylococcus Epidermidis (18%). CV complications were noted in 19/22 patients (86%), the most common being AIS (82%) and IPH (18%). Two patients (9%) were found to have a positive HITS study, both of which developed septic emboli that caused ischemic stroke in one case, and hemorrhagic stroke in the other case. Average days from admission to timing of TCD with HITS study was 8.5 days. 14/22 patients underwent valve surgery (64%) during the admission on average 9.2 days after TCD with HITS study in the negative HITS group versus 5 days in the positive HITS group. Of the positive HITS cases, one of them died inpatient. Conclusion The association between neurological complications in patients with IE and cerebral microemboli detected with TCD monitoring has yet to be elucidated. While our observational study was limited by our sample size, both of our IE patients who had positive TCD with HITS studies developed more severe CV complications, and aggressive care was sought out more urgently to further minimize complications. Future directions include pursuing a prospective study incorporating TCD with HITS monitoring for patients with IE in order to risk‐stratify neurological complications and safety of valve surgery.

Intravenous Drug Use‐Associated Endocarditis Leads to Increased Intracranial Hemorrhage and Neurological Comorbidities

Background The United States is experiencing a rapidly increasing rate of opioid drug abuse. Intravenous drug use (IVDU)‐related endocarditis can lead to significant neurological complications with high morbidity and mortality. When patient care necessitates anticoagulation, the standards for radiographic screening and the risk for intracranial hemorrhage are not clearly elucidated. Methods We conducted a retrospective cohort study involving patients treated for infective endocarditis at a single institution from 2014 to 2018. Patients were grouped based in history of IVDU and their demographics and clinical predictors for intracranial hemorrhage were analyzed. Results A total of 351 patients met inclusion criteria for this study, of whom 170 patients (48%) had a history of IVDU‐associated endocarditis. IVDU was associated with an increased prevalence of intracranial hemorrhage (25.9% versus 13.9%; P =0.005), including intraparenchymal hemorrhage (12.4% versus 5.1%; P =0.012), subarachnoid hemorrhage (17.6 versus 4.4%; P =0.001), and cerebral microbleeds (14.1% versus 7.2%; P =0.022). IVDU was also associated with an increased incidence of infectious intracranial aneurysm (10.6% versus 1.8%; P =0.001) and brain abscesses (4.7% versus 1.1%; P =0.025). Multivariate analysis showed that the presence of intracranial septic emboli (odds ratio [OR], 18.47 [8.4–40.250]; P =0.001) and infectious intracranial aneurysm (OR, 12.38 [3.24–47.28]; P =0.001) as significant predictive factors for intracranial hemorrhage after presenting with endocarditis. Conclusion The opioid epidemic has increased the incidence of infective endocarditis and resultant neurovascular complications. IVDU‐associated endocarditis is associated with increased hemorrhagic stroke and more frequent neurodiagnostic imaging.

Rapid development of an intracranial infectious aneurysm secondary to Streptococcus constellatus infection.

Rapid development of an intracranial infectious aneurysm secondary to Streptococcus constellatus infection.

MRI of unruptured infectious intracranial aneurysms in infective endocarditis. A case-control study

PurposeTo evaluate the usefulness of T2* and FLAIR sequences in the detection of unruptured infectious intracranial aneurysms (UIIAs) in infective endocarditis (IE) including the relationships between the lesion patterns within subarachnoid spaces and the presence of UIIA. MethodsRetrospective review of 15 consecutive patients with definite IE undergoing MR imaging (FLAIR, T2*, DWI, CE-MRA, 3D-T1, CE-3DT1 sequences), in whom DSA detected infectious intracranial aneurysms (IIA). Aneurysmal features (diameter, location, morphology on DSA) and signal patterns onT2*, FLAIR and conventional MR sequences at the site of the UIIA, follow-up MRI and IE background, were analyzed.A control-group of 15 IE-patients without IIA at DSA served for comparison. ResultsAmong 17 UIIAs studied, T2* sequence displayed a susceptibility vessel sign in 15/17 (88.2%), both distal and proximal, which matched with the IIA visualized on DSA. Three patterns of hyposignal areas were identified: (a) signet-ring or target-sign appearance (n = 7), (b) homogeneous, round-, oval- or pear-shaped area (n = 4), and (c) heterogeneous area (n = 4). A FLAIR hyperintensity of the lumen and of the adjacent cortex was present in 6 (35.3%) and 9 (53%) UIIAs, respectively. On T1 (12 UIIAs) a rounded hyposignal (n = 2), within the UIIA lumen matched with the FLAIR hypersignal.Using both T2* and FLAIR had an incremental value with 100% sensitivity and specificity. ConclusionThe susceptibility vessel sign is an MR imaging pattern frequently observed at the site of UIIAs in IE-patients.Both T2* and FLAIR may have the potential to depict UIIAs, regardless of their location and shape.

First case of successful usage of a low-profile flow-diverting stent for treatment of intracranial infectious aneurysm in patient with a mechanical heart valve. Clinical case and literature review

Infectious aneurysms (IA) are cerebral aneurysms that are formed due to the infectious inflammation of the arterial wall. They are a rather rare pathology and in most cases prove to be a complication of infectious (bacterial) endocarditis of the left heart chambers. Timely diagnosis of IA in the pre-hemorrhagic period is problematic due to the variability of the clinical picture of IA, frequent blurred or low-symptomatic clinical course, the possibility of IA formation in the remote period after septic embolism, even despite the background of antibiotic therapy. The presented clinical case illustrates the first successful use of a low-profile flow-diverting stent for the treatment of a young patient with a mechanical heart valve and an infectious aneurysm of the left middle cerebral artery, developed at the site of septic embolism in the acute period of septic bacterial endocarditis accompanied by ischemic stroke. This observation demonstrates the effectiveness of the chosen method of treatment, peculiarities of adequate preoperative preparation, possible postoperative complications and detailed correction of anticoagulant and antiplatelet therapy.

Management and Long-Term Outcomes of Patients With Infectious Intracranial Aneurysms.

Infectious intracranial aneurysms (IIAs) are rare complications of infective endocarditis (IE). Data on management and long-term outcomes remain limited. To retrospectively study long-term outcomes of IIAs in patients treated medically or surgically. Adult cases of IE and/or IIAs admitted to Emory or Grady Healthcare Systems between May 2015 and May 2020 were reviewed for demographic, clinical, and radiographic variables for up to 2 years. Primary outcome measure was 2-year survival. Among 1714 cases of IE, intracerebral hemorrhage occurred in 322 patients and IIAs in 17 patients. The presence of IIAs in IE was associated with higher odds of disposition to hospice/death (odds ratio = 6.9). Including non-IE patients, 24 patients had 38 IIAs mainly involving the distal middle cerebral artery and 16 were ruptured on admission. IIAs were predominantly treated with antibiotics as the primary approach. Open microsurgery was the primary approach for 5 aneurysms and was used as salvage in 7 IIAs. Endovascular management was the primary approach for 2 IIAs and used as salvage for 5 IIAs with antibiotic failure. Medical management had high rate of treatment failure (15/31) which predominantly occurred within 2 weeks of onset. The 2-year survival in this cohort was 70% (17/24). IIAs are rare complications of IE with a poor prognosis. Patients treated with antibiotics have higher risk of treatment failure requiring salvage surgical or endovascular intervention. Medical treatment failure occurred mostly within 2 weeks of onset and had a negative prognostic value emphasizing the need for close follow-up and early surgical or endovascular management.

Intracranial infectious aneurysm caused by infective endocarditis resulting in intracerebral rebleeding following previous surgery for intracerebral hemorrhage: A case report and literature review.

Intracranial infectious aneurysm (IIA) is one of the most severe complications of infective endocarditis (IE). Approximately 2-9% of patients with IE have IIA, which possibly results in severe neurological deficits. Currently, the most common treatment for IIA is endovascular treatment, while excision surgery is less common. The present study describes the case of a 33-year-old male patient who underwent a primary evacuation of an intracerebral hemorrhage (ICH) in the right temporal lobe. The patient was diagnosed with IE and IIA by examinations with an enhanced computed tomography scan, echocardiography and blood culture. In the recovery period after surgery, the patient suffered intracerebral rebleeding and underwent a surgery of IIA excision. The patient finally achieved a good prognosis without severe neurological dysfunction. In summary, IIAs are extremely rare entities, and a rare cause of spontaneous ICH. Previous research has demonstrated that the majority of ruptured IIAs receive endovascular treatment rather than conventional surgery. In the case presented herein, IIA surgical excision was successfully performed and complete pathological results were obtained, which has rarely been reported in the literature. The present case report reinforces the validity of traditional craniotomy according to the characteristics of IIAs.

Cerebral Blood Vessels and Infection

Infectious intracranial aneurysms(IIAs)are rare cerebrovascular complications of systemic infections induced by microbial infiltration and degradation of the arterial vessel wall. Prospective or population-wide studies of the epidemiology, natural history, or management of IIAs have not been conducted. In this study, we present the epidemiological and angiographical features, management, and outcomes of IIAs based on published case series and retrospective studies. Most IIAs were small in size(< 5 mm), with aneurysms located in the middle cerebral artery followed by the posterior cerebral artery. Endovascular interventions for IIAs have increased since coils, liquid embolic materials, and microcatheter became more sophisticated, allowing them to reach more distal branches. Open surgery is still required in cases with large clots or in cases involving branches feeding the eloquent areas, which cannot be sacrificed. These multimodal approaches for managing IIAs have achieved satisfactory results. Septic cavernous sinus thrombosis is also a rare, life-threatening complication of head and neck infections. Several antibiotics and antivirals are used in combination with anticoagulants. However, no consensus has been reached because of a lack of randomized controlled trials and large population-based studies.

P.121 Ruptured intracranial infectious aneurysms: single Canadian center experience

Background: Ruptured Intracranial Infected Aneurysms (IIAs) are relatively rare, but they portend high mortality. To our knowledge, there are no Canadian case-series on IIA, as well there is a relative paucity of international published experiences. Our purpose is to share the experience of a single Canadian tertiary centre in managing ruptured IIA and to conduct a systematic review. Methods: We did a retrospective case review series of adult patients with ruptured IIA treated at our institution. Secondly, we conducted a systematic review of literature on ruptured IIA between 2011-2021 inclusive. Results: At our institution, of a total 8 cases with ruptured IIA, 4 were treated endovascularly and 2 by surgical bypass. For the systematic review, we included 9 non-comparative studies with a total of 509 patients (318 males) and at least 437 ruptured IIA aneurysms. Favourable outcome was specified for 63.3% of patients (n=57). Regarding ruptured IIA, favourable clinical outcome was described in 59.3% (n=16). Conclusions: This study highlights a single Canadian tertiary centre experience in the management of IIA and compares it to the global trends of the last 10 years in a systematic review.

Ruptured intracranial infectious aneurysms: Single Canadian center experience.

Background: Ruptured intracranial infected aneurysms (IIAs) are relatively rare, but they portend high mortality. To the best of our knowledge, there is no Canadian case series on IIA, as well there is a relative paucity of international published experiences. Our purpose is to share the experience of a single Canadian tertiary center in managing ruptured IIA and to conduct a systematic review.Methods: We did a retrospective case review series of adult patients with ruptured IIA treated at our institution. Second, we conducted a systematic review of the literature on ruptured IIA between 2011 and 2021 inclusive.Results: At our institution, of a total eight cases with ruptured IIA, four were treated endovascularly and two by surgical bypass. For the systematic review, we included nine noncomparative studies with a total of 509 patients (318 males) and at least 437 ruptured IIA aneurysms. Favorable outcome was specified for 63.3% of patients (n = 57). Regarding ruptured IIA, favorable clinical outcome was described in 59.3% (n = 16).Conclusion: This study highlights a single Canadian tertiary center experience in the management of IIA and compares it to the global trends of the past 10 years in a systematic review.

Endovascular therapy for intracranial infectious aneurysms associated with a left ventricular assist device: illustrative case.

BACKGROUNDCerebrovascular events and infection are among the most common complications of left ventricular assist device (LVAD) therapy. The authors reported on a patient with an infectious intracranial aneurysm (IIA) associated with LVAD infection that was successfully occluded by endovascular therapy.OBSERVATIONSA 37-year-old man with severe heart failure received an implantable LVAD. He was diagnosed with candidemia due to driveline infection 44 months after LVAD implantation, and empirical antibiotic therapy was started. After 4 days of antibiotic treatment, the patient experienced sudden dizziness. Computed tomography (CT) revealed subarachnoid hemorrhage in the right frontal lobe, and CT angiography revealed multiple aneurysms in the peripheral lesion of the anterior cerebral artery (ACA) and middle cerebral artery. Two weeks and 4 days after the first bleeding, aneurysms on the ACA reruptured. Each aneurysm was treated with endovascular embolization using n-butyl cyanoacrylate. Subsequently, the patient had no rebleeding of IIAs. The LVAD was replaced, and bloodstream infection was controlled. He received a heart transplant and was independent 2 years after the heart transplant.LESSONSLVAD-associated IIAs have high mortality and an increased risk of surgical complications. However, endovascular obliteration may be safe and thus improve prognosis.

Simultaneous intracerebral and subarachnoid hemorrhages caused by multiple infectious intracranial aneurysms treated endovascularly and by microsurgical clipping: illustrative case.

BACKGROUNDInfected intracranial aneurysms are relatively rare but tend to occur in multiple locations. Establishing an optimal treatment strategy for multiple ruptured aneurysms is often challenging, especially when simultaneous ruptures occur in different locations. We report a case of simultaneous intracerebral and subarachnoid hemorrhages caused by the rupture of multiple infected intracranial aneurysms.OBSERVATIONSA 23-year-old male with a 2-week history of chronic fever presented with sudden onset of severe headache and visual disturbance. Computed tomography showed intracerebral hemorrhage in the right occipital lobe and subarachnoid hemorrhage in the area of the left Sylvian fissure. Further investigation documented Staphylococcus bacteremia, verrucae on the mitral valve, and aneurysms arising from the right posterior cerebral artery (PCA) and the left middle cerebral artery (MCA). A larger aneurysm arising from the PCA was successfully occluded endovascularly, but subsequent endovascular occlusion of the MCA aneurysm was unsuccessful because some important branches were observed extending from the aneurysm. The left MCA aneurysm was then obliterated by angioplastic clipping via left pterional craniotomy. The patient showed a favorable neurological recovery after treatment.LESSONSIn such complex cases of infectious aneurysms, the method and timing of treatment need to be carefully determined based on the medical condition.

Timing surgery and hemorrhagic complications in endocarditis with concomitant cerebral complications

BackgroundTo date, limited studies have been conducted regarding the safe timing of valvular repair for infectious endocarditis (IE) in patients with radiographic findings consistent with embolic stroke or infectious intracranial aneurysm (IIA). MethodsA single-center, retrospective review of valvular surgeries for IE was performed (2011–2019). Outcomes for patients who underwent cranial image screening and those who did not were subsequently compared. Results276 patients underwent valvular repair for IE; 186 (67.4%) were male. The mean age was 51.0 (17.4) years. Mean time from imaging to surgery was 7.5 days. 124 (44.9%) underwent baseline cranial imaging. Of these, 22 (17.7%) had findings concerning for ischemic stroke from embolic origin. 65 patients underwent baseline diagnostic cerebral angiography. 10 (15%) of these patients harbored an IIA. Four out of these 10 (40%) underwent intervention for an IIA. Two of the four who underwent intervention (50.0%) had ruptured IIAs. The remaining six (60%) patients with IIAs received treatment with antibiotics alone. None of the patients with IIAs suffered from symptomatic hemorrhage after valvular surgery. No significant difference in symptomatic hemorrhage after valvular surgery between those with ischemic embolic stroke compared to those without (ischemic stroke-4.5% vs. no ischemic stroke-1.0%; p = 0.32). ConclusionsPatients with radiographic evidence of ischemic stroke from septic emboli can safely undergo valvular surgery for IE without increased risk of symptomatic hemorrhage. We advocate for baseline CTA screening to evaluate for IIA in patients who present with a primary diagnosis of IE and propose a management algorithm.

Safety Profile and Factors Associated With Good Outcome for Endovascularly Treated Infectious Intracranial Aneurysms.

Infectious intracranial aneurysms (IIAs), or mycotic aneurysms, are infectious inflammatory lesions that can cause devastating neurological damage or death. Recent systemic reviews have suggested endovascular treatment to be efficacious for IIA management. To compare the safety profile of different endovascular methods for treating ruptured and unruptured IIAs and factors associated with good clinical and radiographic outcomes. We conducted a retrospective single study of endovascularly treated ruptured and unruptured IIAs between 2003 and 2019. Univariate and multivariate analyses were used to study patient presentation, endovascular treatments used, and clinical and radiographic outcomes. Thirty-eight patients with ruptured (n = 20) and unruptured (n = 18) IIAs treated with endovascular methods were included. One patient required retreatment after aneurysm recanalization, and 2 patients demonstrated new infarcts after embolization. There was no postprocedural radiographic hemorrhage or infarct and no difference in clinical and radiographic outcomes comparing treatment modality. Hypertension was associated with ruptured IIA status and worse clinical outcome at 6 mo (odds ratio: 0.03 [95% confidence interval: 0.002-0.52]). In this study, the largest single-center series to date, we showed that endovascular intervention is a safe and effective strategy for both ruptured and unruptured IIAs. Hypertension was associated with ruptured status and worse clinical outcome. Procedures are generally well-tolerated and safe, with good outcomes for patients.

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 1122‐000053: Trends in Intervention Modality for Patients with Mycotic Aneurysms: A Nationwide Analysis

Introduction : Mycotic aneurysms, also known as infectious intracranial aneurysms, are sometimes responsible for intracranial hemorrhage in patients with infective endocarditis. Data regarding when and how to treat mycotic aneurysms most effectively are sparse. Given the widespread adoption of endovascular treatments for non‐infectious intracranial aneurysms and acute stroke, we hypothesized that endovascular treatment is increasingly utilized for patients with mycotic aneurysms. We examined trends in endovascular versus open neurosurgical treatment of mycotic aneurysms in patients with infective endocarditis. Methods : We performed a trends analysis using data from 2000–2015 from the National Inpatient Sample. The National Inpatient Sample is an all‐payer database that includes data for a representative sample of hospitalizations to non‐federal hospitals in the United States. We included all hospitalizations for patients with ruptured (on the basis of subarachnoid hemorrhage) or unruptured cerebral aneurysms alongside a diagnosis of infective endocarditis; diagnoses were ascertained using ICD‐9‐CM codes. Treatment modalities were categorized as endovascular versus open neurosurgical repair based on ICD‐9‐CM procedure codes. National Inpatient Sample survey weights were used to calculate nationally representative estimates. Logistic regression was used to evaluate the association between calendar year and intervention rate, presented as an odds ratio for each additional year. Results : We identified 1,015 hospitalizations for patients with a ruptured or unruptured cerebral aneurysm in the setting of infective endocarditis. Their mean age was 54.6 years (SD, 16.6), and 60.1% were male. The overall rate of intervention was 11.9% (95% CI, 9.6‐14.2%), and this rate did not change appreciably over time (p = 0.772). In comparing intervention modalities over time, there was a decrease in open neurosurgical repair (OR, 0.89; 95% CI, 0.84‐0.95; p = 0.001), offset by an increase in endovascular repair (OR, 1.07; 95% CI, 1.01‐1.14; p = 0.023) (Figure). Conclusions : Rates of mycotic aneurysm intervention during hospitalizations for infective endocarditis have not changed. However, the use of endovascular treatment has become more commonplace while the use of open neurosurgical treatments has decreased. Further directions include understanding whether this shift has improved patients’ outcomes and ultimately enumerating best practices for patients with mycotic aneurysms.

P.147 Ruptured Intracranial Infectious Aneurysms: Single Canadian Center Experience

Background: Ruptured Intracranial Infected Aneurysms (IIAs) are a relatively rare phenomenon, but they portend high mortality. To our knowledge, there are no Canadian studies on IIA with paucity of data on experiences as well. Our purpose is to share experience of a single Canadian tertiary centre in managing ruptured IIA and to conduct a systematic review. Methods: Retrospective case series review of adult patients with ruptured IIA treated at our institution. Secondly, we conducted a systematic review of literature on ruptured IIA between 2011-2021 inclusive. Results: At our institution, with a total 8 cases with ruptured IIA, 4 patients were treated endovascularly and 2 by surgical bypass. For the systematic review, we included 12 non-comparative studies with a total of 547 patients with IIA. Median percentage of ruptured IIA was at least 65.2%, cases that required intervention was 23.7% for surgical cases, and 50% for endovascular cases. The overall median percentage of complications was 5.3%. Conclusions: This study highlights a single Canadian tertiary centre experience in the management of IIA and compares it to the global trends of the last 10 years in a systematic review.

Usefulness of contrast-enhanced 3D MR angiography and contrast-enhanced 3D T1 sequence for detecting intracranial infectious aneurysms in infectious endocarditis

ObjectivesTo assess the diagnostic value of contrast-enhanced MRA (CE MRA) and CE 3D-T1 for identifying intracranial infectious aneurysms (IIAs) in infective endocarditis (IE) with digital substraction angiography (DSA) as reference. MethodsTwenty-one IE patients (14 males; mean age: 53 years) with 30 IIAs, diameter ranging 1.5–15 mm (<3mm, n = 14, 46.7%; 3–5 mm, n = 12,40%), underwent CE MRA and CE 3D-T1 at 1.5 T. Two readers evaluated images for aneurysm detection, characterization, quality of visualization. DSA was obtained at a median of 3 days (range 1–15) after MRI. ResultsThe sensitivity, specificity, positive and negative predictive values and accuracy of IIA detection were respectively: 80%, 100%, 100%, 82.3%, 90% for CE MRA and 86.7%, 100%, 100%, 88.2%, 93.3% for CE 3D T1 compared to DSA.No significant difference was observed between CE MRA and CE 3D-T1 for accuracy and quality of visualization. All IIAs of ≥3 mm in diameter (16/30; 53.%) were identified by both sequences, which were also able to detect IIAs ≤ 3 mm (n = 14/30, 46.7%). False negatives were observed with both sequences for 4 IIAs of <2 mm, 3 being compressed by hemorrhagic lesions. Two other IIAs of <2 mm were overlooked by CE MRA. CE 3D-T1 overestimated IIAs luminal diameter by 8% relatively to DSA (P = NS).Intra and inter-observer agreement were good and similar with both methods. ConclusionBoth CE MRA and CE 3D-T1 have good accuracy compared to DSA detection and characterization of IIAs. CE 3D-T1 also evaluates anatomical relationships of IIAs, which could help DSA location and endovascular treatment.

UNEXPECTED OPPORTUNISTIC INFECTION IN PATIENT WITH SEVERE COVID-19 PNEUMONIA

TOPIC: Chest Infections TYPE: Medical Student/Resident Case Reports INTRODUCTION: The pathogenesis of the novel coronavirus, Covid-19, was characterized by an overdrive of the immune system that lead to some patients to a life-threatening cytokine storm with severe lung inflammation and multiorgan failure. Considering this pathogenic pathway, the use of high dose systemic steroids, and other immunomodulatory therapy was part of the main therapy. As management evolves, complications have risen, including cardiac, thromboembolic, neurologic and secondary infections. Multiple clinical reports have described complications with bacteria, and fungal infections in different organ systems, most commonly the respiratory track. However, systemic and multiorgan infections have been reported due to severe immunosuppression after viral infection and the use of anti-inflammatory therapy. CASE PRESENTATION: We present the case of an 86-year-old male with a past medical history of benign prostate hypertrophy, hyperlipidemia and hypertension who developed respiratory failure due to severe COVID-19 pneumonia, managed with antiviral therapy and high dose dexamethasone. After initial improvement from the respiratory standpoint, the patient developed persistent fungemia with Candida parapsilosis. There was no evidence of endocarditis. The patient presented with persistent altered mental status after cessation of sedation. Brain imaging revealed a right posterior parietal parafalcine hematoma with surrounding vasogenic edema. Angiogram revealed a saccular aneurysm measuring approximately 5.7 mm in largest dimension located at midline posterior frontal in location in relation to pericallosal arteries. Cerebral arterial aneurysm secondary to systemic fungal infection, knowns as mycotic aneurysms, have been reported in medical literature. DISCUSSION: Aneurysms are an abnormal arterial focal dilation which can become infected, but also aneurysmal degeneration of the arterial wall can occur due to bacteremia or a septic embolus;as seen in mycotic aneurisms. Despite its name, most mycotic aneurysms are caused by bacteria from associated endocarditis. This is a serious complication associated to an elevated morbidity and mortality. Several risk factors predispose to infected aneurysm, these include arterial injury, infection, immunocompromised status, atherosclerosis and pre-existing aneurysms. Fungal infections tend to be rare but may occur in immune suppressed patients or as sequelae of treatment of disseminated fungal disease. CONCLUSIONS: This is an unexpected complication of immunosuppression with systemic steroids in management of COVID-19 pneumonia. Treatment with systemic steroid and thromboembolic complication prevention have helped improve COVID-19 pneumonia patient prognosis, however physicians should be careful as it predisposes patients, especially those with advanced age, to opportunistic infections in unexpected organ and settings. REFERENCE #1: WHO Rapid Evidence Appraisal for COVID-19 Therapies (REACT) Working Group, Sterne JAC, Murthy S, Diaz JV, Slutsky AS, Villar J, Angus DC, Annane D, Azevedo LCP, Berwanger O, Cavalcanti AB, Dequin PF, Du B, Emberson J, Fisher D, Giraudeau B, Gordon AC, Granholm A, Green C, Haynes R, Heming N, Higgins JPT, Horby P, Juni P, Landray MJ, Le Gouge A, Leclerc M, Lim WS, Machado FR, McArthur C, Meziani F, Moller MH, Perner A, Petersen MW, Savovic J, Tomazini B, Veiga VC, Webb S, Marshall JC. Association Between Administration of Systemic Corticosteroids and Mortality Among Critically Ill Patients With COVID-19: A Meta-analysis. JAMA. 2020 Oct 6;324(13):1330-1341. doi: 10.1001/jama.2020.17023. PMID: 32876694;PMCID: PMC7489434. REFERENCE #2: Wu FZ, Lai PH. Evolution and regression of intracranial infectious aneurysm diagnosed by brain computed tomographic angiography. Arch Neurol. 2010 Sep;67(9):1147. doi: 10.1001/archneurol.2010.216. PMID: 20837863. REFERENCE #3: World Health Organization. Corticosteroids for COVID-19: Living guidance. https://www.who.int/publications/i/item/WHO-2019-nCoV-Cor icosteroids-2020.1 DISCLOSURES: No relevant relationships by Onix Cantres-Fonseca, source=Web Response No relevant relationships by Porfirio Diaz-Rodriguez, source=Web Response No relevant relationships by Hector Nieves, source=Web Response No relevant relationships by Luis Vazquez, source=Web Response