Management of intracranial infectious aneurysms: a series of 16 cases

Microsurgical management of a ruptured intracranial mycotic aneurysm in infancy

INTRODUCTION

During infancy, infectious aneurysms are uncommon and potentially fatal lesions with an imminent risk of intracranial hemorrhage development.

CASE PRESENTATION

A 1-month-old infant presented with loss of consciousness and clonic movements of the right superior limb after a work-up for Hirschsprung's disease. His physical exam revealed stupor, miosis, anterior fontanelle swelling, and hyperreflexia of the right superior limb. Blood cultures were positive for Candida albicans. In addition, brain imaging revealed an intraparenchymal hematoma in the left temporal lobe and a saccular aneurysm at the M3 segment of the left middle cerebral artery. Upon careful discussion with the patient's family, he underwent evacuation of the hematoma and aneurysm repair. His postoperative clinical course was uneventful. At the 5-month follow-up, a brain MRI showed encephalomalacia in the area of prior hemorrhage. Furthermore, he had preserved motor function and adequate psychomotor development on subsequent pediatric evaluations.

CONCLUSION

Microsurgical management of ruptured mycotic aneurysms demands a systematic work-up and nuanced appraisal of clinical and aneurysmal factors. Operating in a confined space and considering the fragile nature of aneurysms are of utmost relevance for effectively treating these lesions.

Difficulty of diagnosing a mucor-induced aneurysm arising in segment P4 of the posterior cerebral artery – A case report

Background:

Identification of causative pathogen for fungal aneurysm is frequently difficult. We reported the case of a fungal aneurysm caused by Mucor arising in segment P4 of the posterior cerebral artery (PCA) detected only by histopathological examination.

Case Description:

A 50-year-old female complained of nausea and vomiting. Computed tomography showed an intracranial hemorrhage in the left occipital lobe and acute hydrocephalus due to intraventricular hemorrhaging. Digital subtraction angiography performed after external drainage showed a cerebral aneurysm in segment P4 of the left PCA. Surgical excision of the aneurysm and end-to-end anastomosis of the PCA were performed. A histopathological examination revealed that the aneurysm had been caused by a Mucor infection.

Conclusion:

In fungal aneurysm cases, especially those involving Mucor infections, it is difficult to identify the causative fungal infection based on cultures, imaging, and serological tests. Therefore, surgical excision and histopathological diagnosis are important for diagnosing such cases if possible.

Cerebrovascular Complication and Valve Surgery in Infective Endocarditis

Infective endocarditis (IE) with neurologic complications is common in patients with active IE. The most common and feared neurological complication of left-sided IE is cerebrovascular, from septic emboli causing ischemic stroke, intracranial hemorrhage (ICH), or an infectious intracranial aneurysm with or without rupture. In patients with cerebrovascular complications, valve replacement surgery is often delayed for concern of further neurological worsening. However, in circumstances when an indication for valve surgery to treat IE is present, the benefits of early surgical treatment may outweigh the potential neurologic deterioration. Furthermore, valve surgery has been associated with lower in-hospital mortality than medical therapy with intravenous antibiotics alone. Early valve surgery can be performed within 7 days of transient ischemic attack or asymptomatic stroke when medically indicated. Timing of valve surgery for IE after symptomatic medium or large symptomatic ischemic stroke or ICH remains challenging, and current data in the literature are conflicting about the risks and benefits. A delay of 2 to 4 weeks from the time of the cerebrovascular event is often recommended, balancing the risks and benefits of surgery. The range of timing of valve surgery varies depending on the clinical scenario, and is best determined by a multidisciplinary decision between cardiothoracic surgeons, cardiologists, infectious disease experts, and vascular neurologists in an experienced referral center.

Neurologic complications of infective endocarditis

Infective endocarditis (IE) is an infection primarily affecting the endocardium of heart valves that can embolize systemically and to the brain. Neurologic manifestations include strokes, intracerebral hemorrhages, mycotic aneurysms, meningitis, cerebral abscesses, and infections of the spine. Neurologic involvement is associated with worse mortality, though it does not always portend a poor functional prognosis. Neuroimaging is indicated in patients who have neurologic symptoms, including cerebral vessel imaging in patients who have subarachnoid hemorrhage. In the case of acute ischemic stroke (IS), IV thrombolysis is contraindicated but endovascular thrombectomy may be a consideration. Neurologic findings understandably raise concern about valve surgery when indicated due to the risk of hemorrhage with perioperative anticoagulation. However, most neurologic complications do not preclude valve surgery and valve surgery may in fact be indispensable in some cases to prevent further neurologic problems. Management decisions in patients with IE and neurologic complications should therefore be multidisciplinary with a major contribution from the neurologist.

Mycotic (Infected) Pseudoaneurysm, a Diagnostic Challenge - Case Series

Mycotic pseudoaneurysm (or infected pseudoaneurysm) is an infectious arteritis, leading to the destruction of the arterial wall with the formation of a blind, saccular outpouching contiguous with the arterial lumen. Delayed management or non-management of mycotic pseudoaneurysms is associated with high morbidity and mortality due to complications such as arterial rupture, hemorrhage, and fulminant sepsis. Earlier diagnosis of mycotic pseudoaneurysm is essential for time management. Multidetector computed tomography (MDCT) is a widely used imaging modality for detecting the mycotic pseudoaneurysm, its characterization, and vascular mapping. MDCT findings of mycotic pseudoaneurysm are blind, saccular outpouching of an artery with irregular arterial wall, perivascular soft-tissue mass, or edema. Uncommon results of MDCT include arterial lumen thrombosis, arterial wall calcification, and perivascular gas. Management of mycotic pseudoaneurysm includes endovascular stenting with graft repair, endovascular embolization, open surgery, medical therapy (intravenous antibiotics), or a combination of these. We report three cases of mycotic pseudoaneurysm affecting aortic isthmus, a segmental branch of the pulmonary artery, and the internal mammary artery. All cases posed a diagnostic challenge, which only on subsequent imaging revealed to be a mycotic pseudoaneurysm.

The Use of Real-Time 3D Intraoperative Ultrasound "Angiography" in Localization and Occlusion Control of a Ruptured Mycotic Aneurysm: A Case Report

BACKGROUND

 Infectious (mycotic) aneurysms are rare with high mortality and are most commonly found at the distal branches of the middle cerebral artery (MCA). Because aneurysms of the distal MCA are located deep in the Sylvian fissure and are small in size, intraoperative identification and safe clip occlusion of these aneurysms are challenging. Thus, the use of intraoperative imaging and navigation can be beneficial. We describe the use of intraoperative real-time 3D ultrasound "angiography" (3D-iUS) in localizing and occlusion control of a ruptured MCA M3 segment mycotic aneurysm. To our knowledge, its application in the surgery of a ruptured mycotic distal MCA aneurysm is not yet reported.

CLINICAL PRESENTATION

 A 54-year-old woman with a history of septic thrombophlebitis treated with long-term antibiotic therapy presented with sudden onset of headaches, dysphasia, and seizures. Computed tomography (CT) revealed subarachnoid hemorrhage in the distal portion of the left Sylvian fissure. Digital subtraction angiography (DSA) showed an aneurysm at the peripheral branch of the M3 segment of the MCA with characteristics of an infectious aneurysm. A microsurgical treatment was decided. 3D-iUS scan showed an aneurysm within the Sylvian fissure at a depth of 5 cm. The aneurysm was clipped and a repeated 3D-iUS scan showed total occlusion of the aneurysm and patency of the parent artery. The intraoperative findings were confirmed with a postoperative DSA.

CONCLUSION

 Our case report shows that real-time 3D-iUS, despite its limitations, is an important tool to locate and ascertain the successful clip occlusion of an aneurysm, especially when intraoperative angiography (IA) and indocyanine green (ICG) videoangiography are not available due to low-income settings.

Malignant clinical course of mycotic intracranial aneurysms in children: A review

Background:

Mycotic aneurysms are a rare in the pediatric population. The natural history of these lesions and their appropriate management strategies is controversial.

Case Description:

A 13-year-old male presented with the sudden onset of a headache, vomiting, and fever. Inflammatory markers were elevated, and the blood culture was positive for Streptococcus viridans. When the computed tomography angiography (CTA) showed a ruptured mycotic aneurysm accompanied by multiple small unruptured aneurysms, he was started on antibiotics and underwent an urgent craniotomy. Despite negative blood cultures, the follow-up CTA showed further enlargement of the previously diagnosed aneurysms and a new right frontal aneurysm. The second and third craniotomies were, respectively, performed to resect the additional aneurysms. Pathologically, both aneurysmal walls were markedly inflamed and attenuated, suggesting the imminent risk of aneurysmal rupture. Following the total of three craniotomies, the patient had an uneventful postoperative course. Within 2 weeks, he regained baseline neurological function.

Conclusion:

Mycotic aneurysms in children may follow a very malignant course. Aneurysms may grow, new ones may form, and repeated CTAs are required to direct further follow-up treatment.

Systematic Review of Endovascular, Surgical, and Conservative Options for Infectious Intracranial Aneurysms and Cardiac Considerations

INTRODUCTION

With rising rates of intravenous drug use, Infectious Intracranial aneurysms (IIAs) are a relevant topic for investigation. We performed a systematic review to better understand current practice patterns and limits of current published literature.

METHOD

131 publications with a total of 499 patients (665 aneurysms) were included. Of the 499 patients, 83 were single case reports, and 20.5% of the total had multiple aneurysms. 35.8% of all aneurysms were ruptured. Of those reporting treatment, options included conservative antibiotic therapy (30.0%), open surgical intervention (31.1%), and endovascular occlusion (31.8%). Chronologically, publication of IIAs has increased. Usage of endovascular therapies has grown, while conservative and surgical management have declined in the literature. Overall, 56.2% of aneurysms for which conservative therapy was initiated eventually either underwent intervention or death of patient occurred.

RESULTS

The issue of cardiac valve surgery in relationship to aneurysm therapy was discussed in 20.8% (80 patients) of all 384 infectious endocarditis patients; of which 15.0% (12) underwent valve surgery before aneurysm treatment and 85.0 patients (68)% underwent valve surgery after aneurysm treatment. For 51 of the patients where valve surgery followed aneurysm management, the corresponding aneurysm treatment modality could be determined; 58.8% (30) of whom were managed endovascularly. 32.7% (26) of all cases reporting cardiac surgery details underwent cardiac surgery during their admission with the IIA.

CONCLUSIONS

Overall, increasing trend of endovascular management of IIAs is evident, and a strong temporal preference exhibited by providers to perform cardiac surgery subsequently to IIA management.

Ruptured mycotic aneurysms: Report and outcomes of two surgically managed patients

Background:

Mycotic aneurysm is a rare potentially life-threatening complication of infective endocarditis (IE). Little data is available on the management and outcomes of ruptured mycotic aneurysms with large intracerebral hematoma. Few cases have been described on the management of mycotic aneurysm in the presence of life-threatening hematoma and mass effect.

Case Description:

We are presenting two cases of ruptured mycotic aneurysm with intracerebral hematoma and impending brain herniation. Both patients had signs of high intracranial pressure and required urgent surgical evacuation of clot. One patient survived while the other patient expired soon after surgery.

Conclusion:

Mycotic aneurysm of middle cerebral artery (MCA) in IE with intracranial hemorrhage is rare and urgent surgical decompression, and aneurysmal clipping can be lifesaving.

Current Treatment Strategies for Intracranial Aneurysms: An Overview

Intracranial aneurysm is a leading cause of stroke. Its treatment has evolved over the past 2 decades. This review summarizes the treatment strategies for intracranial aneurysms from 3 different perspectives: open surgery approach, transluminal treatment approach, and new technologies being used or trialed. We introduce most of the available treatment techniques in detail, including contralateral clipping, wrapping and clipping, double catheters assisting coiling and waffle-cone technique, and so on. Data from major trials such as Analysis of Treatment by Endovascular approach of Non-ruptured Aneurysms (ATENA), Internal Subarachnoid Trial (ISAT), Clinical and Anatomical Results in the Treatment of Ruptured Intracranial Aneurysms (CLARITY), and Barrow Ruptured Aneurysm Trial (BRAT) as well as information from other clinical reports and local experience are reviewed to suggest a clinical pathway for treating different types of intracranial aneurysms. It will be a valuable supplement to the current existing guidelines. We hope it could help assisting real-time decision-making in clinical practices and also encourage advancements in managing the disease.

The anterior temporal artery: an underutilized but robust donor for revascularization of the distal middle cerebral artery

OBJECTIVE The anterior temporal artery (ATA) supplies an area of the brain that, if sacrificed, does not cause a noticeable loss of function. Therefore, the ATA may be used as a donor in intracranial-intracranial (IC-IC) bypass procedures. The capacities of the ATA as a donor have not been studied previously. In this study, the authors assessed the feasibility of using the ATA as a donor for revascularization of different segments of the distal middle cerebral artery (MCA). METHODS The ATA was studied in 15 cadaveric specimens (8 heads, excluding 1 side). First, the cisternal segment of the artery was untethered from arachnoid adhesions and small branches feeding the anterior temporal lobe and insular cortex, to evaluate its capacity for a side-to-side bypass to insular, opercular, and cortical segments of the MCA. Any branch entering the anterior perforated substance was preserved. Then, the ATA was cut at the opercular-cortical junction and the capacity for an end-to-side bypass was assessed. RESULTS From a total of 17 ATAs, 4 (23.5%) arose as an early MCA branch. The anterior insular zone and the frontal parasylvian cortical arteries were the best targets (in terms of mobility and caliber match) for a side-to-side bypass. Most of the insula was accessible for end-to-side bypass, but anterior zones of the insula were more accessible than posterior zones. End-to-side bypass was feasible for most recipient cortical arteries along the opercula, except for posterior temporal and parietal regions. Early ATAs reached significantly farther on the insular MCA recipients than non-early ATAs for both side-to-side and end-to-side bypasses. CONCLUSIONS The ATA is a robust arterial donor for IC-IC bypass procedures, including side-to-side and end-to-side techniques. The evidence provided in this work supports the use of the ATA as a donor for distal MCA revascularization in well-selected patients.

Interdisciplinary Treatment of Intracranial Infectious Aneurysms

OBJECTIVE

Intracranial infectious aneurysms (IIAs) are a rare clinical entity without a definitive treatment guideline. In this study, we evaluate the treatment options of these lesions based on our own clinical experience and review the current knowledge of therapy as portrayed in the literature.

METHODS

We conducted a single-center retrospective analysis of all patients with an IIA and performed a systematic review of the literature using the MEDLINE database. We undertook a comprehensive literature search using the OVID gateway of the MEDLINE database (1950-October 2015) using the following keywords (in combination): 'infectious', 'mycotic', 'cerebral aneurysm', 'intracranial aneurysm'. 1,721 potentially relevant abstracts were identified and 63 studies were selected for full review. The studies were analysed regarding ruptured versus unruptured aneurysms, aneurysm localization and treatment, as well as clinical and radiological outcome.

RESULTS

Our institutional series consisted of 6 patients (median age 57 [32-76]) treated between 2011 and 2015. All patients presented with ruptured IIAs located on the middle cerebral artery (MCA, 5 patients) and anterior cerebral artery (ACA, 1 patient). Five patients were treated by clipping and resecting the aneurysm, 1 patient underwent coiling. All patients received antibiotic therapy and 1 patient died. We further identified 814 patients (median age 35.5 [0-81]) in 63 studies. Locations of the aneurysms were mentioned in 55 studies. The most frequent locations of the aneurysms were: MCA (63.5%), posterior cerebral artery (14%), ACA (9.0%) and others (13.5%). Treatment for IIAs was described in 62 studies: antibiotic treatment (56.1%), a combination of antibiotics and surgery (20.9%) or antibiotics and endovascular treatment (23.0%). Outcome was mentioned in 82.4% of the patients with a mortality rate of 16.8%. An evaluation of treatment outcome was limited due to the heterogeneity of patients in the published case series.

CONCLUSION

Antibiotic therapy of patients with IIA is mandatory. However, due to the complexity of the disease and its accompanying comorbidities, a general treatment algorithm could not be defined. Analogous to non-mycotic aneurysms, further treatment decisions require an interdisciplinary approach involving neurosurgeons, interventionists and infectious disease specialists.

A case of ruptured infectious anterior cerebral artery aneurysm treated by interposition graft bypass using the superficial temporal artery

Background:

To describe the application of an interposition graft bypass using superficial temporal artery (STA) for the treatment of a ruptured anterior cerebral artery (ACA) infectious aneurysm.

Case Description:

A 30-year-old male suffered from severe headache with high fever. The patient's diagnosis was ruptured infectious ACA aneurysm at the A3 segment with a maximum diameter of 4.5 mm, caused by infectious endocarditis. The patient was initially treated with high-dose intravenous antibiotics. Follow-up digital subtraction angiography (DSA) revealed that the fusiform aneurysm had enlarged to a maximum diameter of 14.0 mm. A left paracentral artery, supplying the motor area of the left lower extremity, originated from the body of this aneurysm. Because the angiographic findings suggested a risk of recurrent bleeding, the patient underwent open surgery. Interposition graft bypass using the STA was performed to reconstruct the left A3 segment in an end-to-side manner (left proximal callosomarginal artery – STA graft – left distal pericallosal artery). Then, the origin of the left paracentral artery was cut and anastomosed to the STA graft in an end-to-side manner. The affected parent artery was trapped, and the aneurysm was resected. Postoperative magnetic resonance imaging showed no ischemic or hemorrhagic complications, and postoperative DSA revealed the patency of the interposition graft. Pathological diagnosis of the resected aneurysm revealed features corresponding to infectious cerebral aneurysm. The postoperative course was uneventful, and the patient was discharged without any neurological deficits.

Conclusion:

In the treatment of infectious cerebral aneurysms, revascularization should be considered when the affected artery supplies the eloquent area. Interposition graft bypass using the STA is one of the options for revascularization surgery for the treatment of infectious ACA aneurysms.

Results and current trends of multimodality treatment for infectious intracranial aneurysms

The authors retrospectively reviewed their cases of infectious intracranial aneurysms and discuss results and trends of current treatment modalities including medical, neurosurgical, and endovascular. Twenty patients (10 males and 10 females; mean age 46 years) with 23 infectious aneurysms were treated by various treatment modalities during a 15-year period. Fifteen cases (75.0%) were caused by infective endocarditis. Eleven aneurysms (47.8%) were ruptured. Two aneurysms (8.7%) presented a mass effect and 7 (30.4%) were unruptured and asymptomatic. The average aneurysm size was 6.5 ± 4.8 mm (range 1–22 mm). The aneurysms were located in proximal cerebral circulation in 7 (30.4%) and distal in 16 (69.6%). Six (26.1%) aneurysms were treated surgically (5: trapping, 1: neck clipping), 10 (43.5%) endovascularly (7: trapping, 2: proximal occlusion, 1: saccular coiling), and the remaining 7 (30.4%) medically. Endovascular treatment was gradually increased with time. Medical and surgical treatments were continuously performed during the study period. Surgery was preferred for the patient with intraparenchymal hematoma or treated by bypass surgery. Three periprocedural minor complications occurred in endovascular treatment. There was one postoperative infarction with permanent deficit developed from surgical treatment. During the follow-up period (mean 28.8 months), none of the aneurysms presented a recurrence or rebleeding. Thirteen patients (65.0%) had favorable clinical outcomes (modified Rankin Scale: 0–2), although four (20.0%) had poor outcomes (modified Rankin Score: 5–6). A multimodal approach for the management of infectious aneurysms achieved satisfactory results. Endovascular intervention is a feasible and efficacious treatment option and surgical intervention is still an indispensable procedure.

Mycotic aneurysm detection rates with cerebral angiography in patients with infective endocarditis

BACKGROUND

Cerebral angiography remains the gold standard for the detection of mycotic aneurysms, and it has been estimated that ruptured mycotic aneurysms result in 5% of the neurological complications of patients with infective endocarditis (IE).

OBJECTIVE

To determine the diagnostic yield of cerebral angiography in the above patient population and to assess patient factors that might suggest greater or lesser utility.

METHODS

We retrospectively reviewed 168 patients who underwent cerebral angiography with a diagnosis of IE or infected left ventricular assist device at the Cleveland Clinic between January 2003 and March 2010 in accordance with institutional review board guidelines. Chart and imaging review was performed.

RESULTS

15/168 patients (8.9%) had mycotic aneurysms; 93.3% (14/15) of the patients with mycotic aneurysms presented with CNS hemorrhage and 66.7% (10/15) had acute ischemic findings. Of the 15 patients with mycotic aneurysms on angiography, seven underwent CT angiography and six underwent MR angiography, which showed mycotic aneurysms in three (42.9%) and two cases (one of which was questionable; 33.3%), respectively.

CONCLUSIONS

Patients with IE or similar sources of central bacterial emboli are prone to neurovascular complications. Approximately 9% of patients with IE at our institution who undergo cerebral angiography have mycotic aneurysms. Presentation with hemorrhage appears to be more predictive of aneurysm, as approximately 22% of patients with IE and hemorrhage were found to have an aneurysm compared with only 1% when hemorrhage was absent. Thus, patients with IE presenting with intracranial hemorrhage should undergo vascular imaging, preferably with cerebral angiography.

Symptomatic peripheral mycotic aneurysms due to infective endocarditis: a contemporary profile

Peripheral mycotic aneurysms (PMAs) are a relatively rare but serious complication of infective endocarditis (IE). We conducted the current study to describe and compare the current epidemiologic, microbiologic, clinical, diagnostic, therapeutic, and prognostic characteristics of patients with symptomatic PMAs (SPMAs). A descriptive, comparative, retrospective observational study was performed in 3 tertiary hospitals, which are reference centers for cardiac surgery. From 922 definite IE episodes collected from 1996 to 2011, 18 patients (1.9%) had SPMAs. Because all SPMAs developed in left-sided IE, we performed a comparative study between 719 episodes of left-sided IE without SPMAs and 18 episodes with SPMAs. We found a higher frequency of intravenous drug abuse, native valve IE, intracranial bleeding, septic emboli, multiple embolisms, and IE diagnostic delay >30 days in patients with SPMAs than in patients without SPMAs. The causal microorganisms were gram-positive cocci (n =10), gram-negative bacilli (n = 2), gram-positive bacilli (n = 3), Bartonella henselae (n = 1), Candida albicans (n = 1), and negative culture (n = 1). The median IE diagnosis delay was 15 days (interquartile range [IQR], 13-33 d) in the case of high-virulence microorganisms versus 45 days (IQR, 30-240 d) in the case of low- to medium-virulence microorganisms. Twelve SPMAs were intracranial and 6 were extracranial. In 10 cases (8 intracranial and 2 extracranial), SPMAs were the initial presentation of IE; the remaining cases developed symptoms during or after finishing parenteral antibiotic treatment. The initial diagnosis of intracranial SPMAs was made by computed tomography (CT) or magnetic resonance imaging in 6 unruptured aneurysms and by angiography in 6 ruptured aneurysms. The initial test in extracranial SPMAs was Doppler ultrasonography in limbs, CT in liver, and coronary angiography in heart. Four (3 intracranial, 1 extracranial) of 7 (6 intracranial, 1 extracranial) patients treated only with antibiotics died. Surgical resection was performed in 7 (3 intracranial, 4 extracranial) and endovascular repair in 4 (3 intracranial, 1 extracranial) patients; all of them survived. In conclusion, we found that SPMAs were a rare complication of IE that developed only in left-sided IE, and especially in native valves. Intracranial hemorrhage, embolism, multiple embolisms, and diagnostic delay of IE were more common in patients with SPMAs. The microbiologic profile was diverse, but microorganisms of low-medium virulence were predominant, and had a greater delayed diagnosis of IE than those caused by microorganisms of high virulence. SPMAs were often the initial presentation of IE. The most common location of SPMAs was intracranial. Noninvasive radiologic imaging techniques were the initial imaging test in intracranial unruptured SPMAs and in most extracranial SPMAs. Surgical and endovascular treatments were safe and effective. Endovascular treatment could be the first line of treatment in selected cases. Mortality was high in those cases treated only with antibiotics.

Endovascular treatment of cerebral mycotic aneurysm: a review of the literature and single center experience

The management of mycotic aneurysm has always been subject to controversy. The aim of this paper is to review the literature on the intracranial infected aneurysm from pathogenesis till management while focusing mainly on the endovascular interventions. This novel solution seems to provide additional benefits and long-term favorable outcomes.

Cerebral hyperperfusion syndrome following the excision of a mycotic aneurysm with superficial temporal artery-to-middle cerebral artery bypass: case report

The authors report a rare case of cerebral hyperperfusion syndrome (HPS) following the excision of a mycotic aneurysm with superficial temporal artery-to-middle cerebral artery (STA-MCA) bypass. A 74-year-old woman with infective endocarditis presented with progressive cerebral infarction and subarachnoid hemorrhage due to a mycotic aneurysm, which was excised with a STA-MCA bypass. Postoperatively, the patient developed HPS that was considered to be exacerbated by a previous ischemic event. Therefore, cerebral hemodynamics should be evaluated before bypass surgery to prevent subsequent hyperperfusion.

Ruptured mycotic cerebral aneurysm development from pseudoocclusion due to septic embolism

Background:

Cerebral mycotic aneurysms are rare sequelae of systemic infections that can cause profound morbidity and mortality with rupture. Direct bacterial extension and vessel integrity compromise from septic emboli have been implicated as mechanisms for formation of these lesions. We report the 5-day development of a ruptured mycotic aneurysm arising from a septic embolism that caused a focal M1 pseudoocclusion.

Case Description:

A 14-year-old girl developed acute left-sided hemiparesis while hospitalized for subacute bacterial endocarditis that was found after she presented with a 2-week history of fever, myalgia, shortness of breath, and lethargy. Mitral valve vegetations were confirmed in the setting of hemophilus bacteremia. Brain magnetic resonance (MR) imaging and angiography confirmed middle cerebral artery infarct with focal pseudoocclusion of the distal M1 segment. Given that further middle cerebral artery territory was at risk, a trial of heparin was attempted for revascularization but required discontinuation owing to hemorrhagic conversion. Decline of the patient's mental status necessitated craniectomy for decompression. Postoperatively, her mental status improved with residual left hemiparesis. On the third postoperative day (5 days after MR angiography), the patient's neurologic condition acutely declined, with development of right-sided mydriasis. Computed tomography (CT) angiography revealed a ruptured 19 × 16 mm pseudoaneurysm arising from the M1 site of the previous occlusion. Emergent coiling of aneurysm and parent vessel followed by hematoma evacuation ensued. At discharge, the patient had residual left hemiparesis but intact speech and cognition.

Conclusion:

Focal occlusions due to septic emboli should be considered high-risk for mycotic aneurysm formation, prompting aggressive monitoring with neuroimaging and treatment when indicated.

Ruptured mycotic aneurysm of the distal middle cerebral artery manifesting as subacute subdural hematoma

Mycotic aneurysms are rare inflammatory neurovascular lesions. Ruptured mycotic aneurysm manifesting as subdural hematoma is extremely rare. A 72-year-old male patient was admitted to our hospital with headache and drowsiness. Computer tomography (CT) of brain and CT angiography revealed subdural hematoma and an aneurysm located at the M4 segment of the left middle cerebral artery (MCA). Cerebral angiogram revealed 2 aneurysms; one located at the left distal MCA and the other at the bifurcation of left MCA. Laboratory studies showed leukocytosis and elevated inflammatory factors. The patent was treated with antibiotic therapy for 4 weeks. The follow-up CT and cerebral angiography showed that the mycotic aneurysm was completely resolved, and the patient was nearly free of symptoms.

Endovascular treatment of a mycotic intracavernous carotid artery aneurysm using a stent graft

Intracavernous carotid artery mycotic aneurysms are rare and management is determined by clinical presentation. We describe the first documented proximal intracranial mycotic aneurysm treated by a balloon expandable Aneugraft PCS covered stent. An 11-year-old female child presented with acute onset fever, headache, chemosis followed by diplopia, right-sided ptosis with ophthalmoplegia. Magnetic resonance imaging revealed bilateral cavernous sinus thrombosis. Subsequent work-up included serial computed tomographic arteriography and digital subtraction angiography which revealed a progressively enlarging intracavernous carotid aneurysm. An Aneugraft PCS covered stent was successfully deployed endovascularly, and complete exclusion of the aneurysm was achieved while maintaining the patency of the parent artery. The use of covered stents in intracranial vasculature can be an effective and safe treatment modality for exclusion of the mycotic aneurysm in selected cases.

Current treatment of active infective endocarditis with brain complications

We describe the optimal timing of surgery in active infective endocarditis patients with brain complications. (1) Non-hemorrhagic infarction: elective surgery has been recommended in patients with non-hemorrhagic infarction. However, the timing is changing to an earlier phase. Recent studies have shown that silent brain embolism and small-size infarction (15-20 mm) without coma can be operated safely without delay. On the other hand, in patients with large non-hemorrhagic infarction with impaired consciousness, early surgery is not recommended. (2) Non-ruptured infectious intracranial aneurysm: treatment strategies for patients with infectious aneurysms without rupture remain controversial. However, the treatments are generally as follows. If the intracranial aneurysm without rupture decreases in size by administration of effective antibiotics, neurosurgery will not be required and cardiac surgery can be prioritized without delay. When the aneurysm without rupture enlarges and changes its morphology, neurosurgery or endovascular surgery should be prioritized to prevent its rupture. (3) Hemorrhagic stroke: this type is classified into primary intra-cerebral hemorrhage due to simple necrotic arteritis, hemorrhagic transformation of ischemic infarcts, and rupture of intracranial infectious aneurysms. Among these, primary intracerebral hemorrhage is the most frequently observed. In patients with the primary intracerebral hemorrhage, surgery must be postponed for at least 4 weeks to prevent exacerbation of bleeding. In patients with ruptured infectious aneurysm, neurosurgery or endovascular surgery is performed initially and cardiac surgery should be postponed at least 2-3 weeks.

Fatal mycotic aneurysms due to Scedosporium and Pseudallescheria infection

Angioinvasive complications of Scedosporium infections are rare. We report two cases of mycotic aneurysm, following apparent localized infection, due to Scedosporium apiospermum and Pseudallescheria boydii. The thoracoabdominal aorta was affected in one patient, and cerebral vessels were affected in the other. Despite voriconazole therapy and surgical resection, the patients died. Previously reported cases are reviewed.

Significance of the T2*-weighted gradient echo brain imaging in patients with infective endocarditis

BACKGROUND

Although aneurysm formation accompanying parenchymal hemorrhage is one of devastating complications in the central nerves system (CNS), imaging studies of the brain are not routinely warranted in patients with infective endocarditis (IE). To assess the clinical importance for detecting silent lesions in the central nervous system, we investigated hypointense signal spots detected on the brain T2*-weighted MR imaging in patients with IE.

METHODS AND RESULTS

Eleven patients with IE were retrospectively reviewed. Seven patients (63.6%) showed hypointense signal spots on T2*-weighted MR images. The number of hypointense signal spots increased within only a few weeks in five patients.

CONCLUSION

The brain T2*-weighted MR imaging in patients with IE may have a potential role to detect CNS lesions with clinical significance of potentially high risk of intracranial hemorrhage. T2*-weighted hypointense signal spots may be specific to brain involvement, and be quite useful in monitoring CNS lesions associated with IE, even if they are asymptomatic.

Early Endovascular Coiling of Posterior Communicating Artery Saccular Aneurysm in the Setting of Staphylococcus Bacteremia

OBJECTIVE

Although infectious complications of endovascular aneurysm treatment are in general rare, platinum coil therapy for patients with ruptured cerebral aneurysms and active bacteremia could be expected to carry increased risk. The literature on the timing and safety of endovascular treatment in this setting, however, is limited. In this report, the authors present a case of aneurysmal subarachnoid hemorrhage and active bacteremia in which intravenous antibiotics and early endovascular therapy were successfully used. A review of the literature is also provided.

CLINICAL PRESENTATION

A 79-year-old woman presented with Hunt-Hess grade 4, Fisher grade 3 + 4 subarachnoid hemorrhage. Blood cultures obtained on admission revealed gram-positive cocci, which later proved to be coagulase-negative Staphylococcus.

INTERVENTION

Intravenous cefepime and vancomycin were begun soon after admission. A right posterior communicating artery saccular aneurysm was identified on diagnostic cerebral angiography and was treated with bare platinum coils 28 hours after antibiotic therapy was initiated. An extended course of vancomycin was completed. No intracranial infectious complications were noted at 34-month clinical and radiographic follow-up.

CONCLUSION

This is the first case report to document the efficacy and safety of early endovascular coil embolization of a ruptured saccular cerebral aneurysm presenting in the context of active bacteremia. Review of the available literature suggests that a similar strategy for ruptured infectious aneurysms may also be safe. Further validation of this approach for both saccular and infectious aneurysms, however, is required.

Endovascular treatment for intracranial infectious aneurysms

OBJECTIVE

To re-enforce an alternative, less aggressive treatment modality in the management of intracranial infectious aneurysms.

METHOD

We present a series of five patients with infectious endocarditis and intracranial infectious aneurysms (mycotic aneurysms) managed by means of endovascular treatment.

RESULTS

Endovascular treatment was executed technically uneventfully in all patients. Three patients had favorable clinical outcome: two were classified as Glasgow Outcome Scale 4/5, and one had total neurological recovery (GOS 5/5). Two patients died (GOS 1/5), one in consequence of the initial intracranial bleeding and the other after cardiac complications from endocarditis and open-heart surgery.

CONCLUSION

Endovascular techniques are an expanding option for the treatment of IIAs. It has been especially useful for infectious endocarditis patients with IIA, who will be submitted to cardiac surgery with cardiopulmonary bypass and anticoagulation, with the risk of intracranial bleeding.

Intracranial infectious aneurysms: a comprehensive review

Intracranial infectious aneurysms, or mycotic aneurysms, are rare infectious cerebrovascular lesions which arise through microbial infection of the cerebral arterial wall. Due to the rarity of these lesions, the variability in their clinical presentations, and the lack of population-based epidemiological data, there is no widely accepted management methodology. We undertook a comprehensive literature search using the OVID gateway of the MEDLINE database (1950-2009) using the following keywords (singly and in combination): "infectious," "mycotic," "cerebral aneurysm," and "intracranial aneurysm." We identified 27 published clinical series describing a total of 287 patients in the English literature that presented demographic and clinical data regarding presentation, treatment, and outcome of patients with mycotic aneurysms. We then synthesized the available data into a combined cohort to more closely estimate the true demographic and clinical characteristics of this disease. We follow by presenting a comprehensive review of mycotic aneurysms, highlighting current treatment paradigms. The literature supports the administration of antibiotics in conjunction with surgical or endovascular intervention depending on the character and location of the aneurysm, as well as the clinical status of the patient. Mycotic aneurysms comprise an important subtype of potentially life-threatening cerebrovascular lesions, and further prospective studies are warranted to define outcome following both conservative and surgical or endovascular treatment.