Acute Treatment of Isolated Posterior Cerebral Artery Occlusion: Single Center Experience.

BACKGROUND AND OBJECTIVES: Randomized trials for mechanical thrombectomy (MT) excluded patients with ischemic strokes due to isolated posterior cerebral artery occlusion (IPCAO), and there is no evidence for best acute treatment strategy in these patients. We aimed to assess the effectiveness and safety of MT in acute IPCAO. METHODS: We retrospectively analyzed consecutive patients with acute stroke due to IPCAO submitted to MT and/or intravenous thrombolysis (IVT), between 2015-2019. Effectiveness outcomes (recanalization rate, first-pass effect, NIHSS 24h improvement and 3-month Modified Ranking Scale - mRS) and safety outcomes (complications, symptomatic intracranial hemorrhage (SICH) and 3-month mortality) were described and compared between groups. RESULTS: A total of 38 patients were included, 25 underwent MT and 13 had IVT alone. Successful and complete recanalization were achieved in 68% and 52% of MT patients, respectively. NIHSS improvement at 24h was found in 56% of MT patients versus 30.8% of patients submitted to IVT alone (OR [95% CI]=2.86 [0.69-11.82]) and excellent functional outcome at 3 months (mRS≤1) was achieved in 54.2% of MT patients versus 38.5% in the IVT group (OR [95% CI]=1.60 [0.41-6.32]). Complications occurred in 3 (12%) procedures and there were no SICH. Mortality at 3 months was 20% in the MT group and 15.4% in patients submitted to IVT alone. CONCLUSIONS: Our results reflect a real-world scenario in a single center and seem to support the recently growing literature showing that MT is a feasible and safe treatment in IPCAO, with favorable effectiveness.

Mechanical thrombectomy in stroke in nonagenarians: useful or futile?

BACKGROUND: Mechanical thrombectomy is the standard treatment in acute ischemic stroke due to large vessel occlusion, but there is limited evidence about its efficacy in very old patients. We sought to analyse safety and effectiveness of mechanical thrombectomy in nonagenarian versus octagenarian patients. METHODS: We included consecutive patients with acute ischemic stroke due to large vessel occlusion subjected to mechanical thrombectomy, during 29 months in a tertiary center. Patients were divided into two sub-groups, according to age: 80-89 and >90 years old. Recanalization, complications, functional outcome and mortality at discharge and at 3 months were compared. Multivariable analysis was performed to identify independent predictors of functional outcome at 3 months of follow-up, assessed by the modified Rankin Scale. RESULTS: A total of 128 octogenarians (88.9%) and 16 nonagenarians (11.1%) met the inclusion criteria. Successful revascularization was achieved in 87.5% of octagenarians and in 81.3% of nonagenarians (p = 0.486). Symptomatic hemorrhage occurred in 3.1% and 6.3% of younger and older patients, respectively (p = 0.520). Cerebral edema occured in 35.2% of octagenarians versus 25.0% of nonagenarians (p = 0.419). Functional independence (mRS ≤ 2) at 3 months was achieved in 28 (22.6%) and 5 (31.3%) of octagenarians and nonagenarians, respectively (p = 0.445). Mortality at 3 months was not significantly higher in nonagenarians (37.5%) versus octagenarians (33.9%, p = 0.773). CONCLUSIONS: No significant diferences were found in functional outcome, mortality, recanalization and complication rates between octagenarians and nonagenarians submitted to mechanical thrombectomy, underlining that patients should not be excluded from mechanical thrombectomy based on age alone.

Analysis of metal artifact reduction tools for dental hardware in CT scans of the oral cavity: kVp, iterative reconstruction, dual-energy CT, metal artifact reduction software: does it make a difference?

INTRODUCTION: Metal artifacts may negatively affect radiologic assessment in the oral cavity. The aim of this study was to evaluate different metal artifact reduction techniques for metal artifacts induced by dental hardware in CT scans of the oral cavity. METHODS: Clinical image quality was assessed using a Thiel-embalmed cadaver. A Catphan phantom and a polymethylmethacrylate (PMMA) phantom were used to evaluate physical-technical image quality parameters such as artifact area, artifact index (AI), and contrast detail (IQFinv). Metal cylinders were inserted in each phantom to create metal artifacts. CT images of both phantoms and the Thiel-embalmed cadaver were acquired on a multislice CT scanner using 80, 100, 120, and 140 kVp; model-based iterative reconstruction (Veo); and synthesized monochromatic keV images with and without metal artifact reduction software (MARs). Four radiologists assessed the clinical image quality, using an image criteria score (ICS). RESULTS: Significant influence of increasing kVp and the use of Veo was found on clinical image quality (p = 0.007 and p = 0.014, respectively). Application of MARs resulted in a smaller artifact area (p < 0.05). However, MARs reconstructed images resulted in lower ICS. CONCLUSION: Of all investigated techniques, Veo shows to be most promising, with a significant improvement of both the clinical and physical-technical image quality without adversely affecting contrast detail. MARs reconstruction in CT images of the oral cavity to reduce dental hardware metallic artifacts is not sufficient and may even adversely influence the image quality.

Subdural Empyema as a Complication of Sinusitis: A Diagnosis to Keep in Mind.

Subdural empyema (SDE) is a rare form of intracranial infection associated with a high morbidity and mortality rate. Infections of the middle ear and paranasal sinuses are the most common predisposing factors that can lead to bacterial proliferation in the subdural space, usually by direct extension in young patients. Clinicians must have a high level of suspicion for patients presenting with concomitant neurological deficits and signs of sinus pathology. Cross-sectional imaging is mandatory for the diagnosis, preferably contrast-enhanced magnetic resonance imaging. Treatment requires a prolonged course of intravenous antibiotherapy and prompt neurosurgical drainage intervention. Here, we present the case of a 20-year-old patient with long-term neurological sequelae following a left paranasal infection complicated by an SDE. This case report highlights the rapid progression and devastating consequences of SDE, an ominous neurosurgical emergency.

Cerebral cavernous malformations: Typical and atypical imaging characteristics.

Cavernous malformations (CMs) are benign vascular malformations that maybe seen anywhere in the central nervous system. They are dynamic lesions, growing or shrinking over time and only rarely remaining stable. Size varies from a few millimeters to a few centimeters. CMs can be sporadic or familial, and while most of them are congenital, de novo and acquired lesions may also be seen. Etiology is still unknown. A genetic molecular mechanism has been proposed since a cerebral cavernous malformation gene loss of function was found in both familial and sporadic lesions. Additionally, recent studies suggest that formation of CMs in humans may be associated with a distinctive bacterial gut composition (microbioma). Imaging is fairly typical but may vary according to age, location, and etiology. Follow-up is not well established because CMs patients have a highly unpredictable clinical course. Angiogenic and inflammatory mechanisms have been implicated in disease activity, as well as lesional hyperpermeability and iron deposition. Imaging and serum biomarkers of these mechanisms are under current investigation. Treatment options, including surgery or radiosurgery, are not well defined and are dependent upon multiple factors, including clinical presentation, lesion location, number of hemorrhagic events, and medical comorbidities. Our purpose is to review the imaging features of CMs based on their size, location, and etiology, as well as their differential diagnosis and best imaging approach. New insights in etiology will be briefly considered. Follow-up strategies, including serum and imaging biomarkers, and treatment options will also be discussed.

Endovascular Treatment of Brain Arteriovenous Malformations in Pediatric Patients: A Single Center Experience and Review of the Literature.

BACKGROUND: Brain arteriovenous malformations (bAVMs) are abnormal vascular connections with direct arteriovenous shunts, generally symptomatic in the adult life. However, a small number of bAVMs may manifest in pediatric patients, with higher bleeding risk and mortality rates when compared to adults. The purpose of this study is to review our experience with endovascular treatment of bAVMs in pediatric patients. METHODS: This is a retrospective analysis of all bAVMs in pediatric patients (0-18 years) who underwent diagnostic digital subtraction angiography (DSA) at our institution from January 2010 to June 2021. RESULTS: Twenty-six patients met the inclusion criteria, of which 12 underwent endovascular treatment. Treated patients had a mean age of 10.25 years and 58% were females. Complete angiographic exclusion was achieved in five (42%) patients with endovascular treatment. Five patients with residual bAVM after embolization needed adjuvant therapy with surgery (n = 3) or stereotactic radiosurgery (SRS; n = 2). Two patients are still undergoing embolization sessions. Procedure-related complications occurred in two patients (17%) and included small vessel perforation and an occipital ischemic stroke. Two patients showed bAVM recurrence on follow-up (17%) and subsequently underwent SRS (n = 1) or surgery (n = 1), both resulting in complete bAVM exclusion. All patients had a modified Rankin scale (mRS) score of 0 to 2 on follow-up. CONCLUSION: Our experience supports the effectiveness and safety of endovascular treatment of bAVM in selected pediatric patients. A multidisciplinary approach combining surgery and SRS is warranted to achieve higher complete bAVM obliteration rates. Long-term follow-up is important as these lesions may show recurrence over time, especially in the pediatric population.

Reversible contrast-induced encephalopathy after coil embolization of epistaxis. / Encefalopatia reversível induzida por contraste após embolização com espiras por epistaxe.

A 37-year-old woman (35 weeks pregnant) was admitted to a local hospital due to severe epistaxis resulting in shock and the need for emergency cesarean section. After failure to tamponade the bleeding, angiographic treatment was provided. After the procedure, she was admitted to the neurocritical intensive care unit and was confused and agitated, requiring sedation and endotracheal intubation. In the intensive care unit, diagnostic investigations included brain magnetic resonance imaging, lumbar puncture with viral panel, electroencephalogram, tests for autoimmunity, and hydroelectrolytic and metabolic evaluations. Magnetic resonance imaging showed a puntiform restricted diffusion area on the left corona radiata on diffusion weighted imaging and mild cortical posterior edema (without restricted diffusion), and an electroencephalogram showed moderate diffuse slow activity and fronto-temporal slow activity of the left hemisphere with associated scarce paroxysmal components. The other exams did not show any relevant alterations. Due to the temporal relationship, the clinical history and the magnetic resonance imaging results, a diagnosis of contrast-induced encephalopathy was made. After 2 days in the intensive care unit, sedation was withdrawn, the patient was extubated, and total neurological recovery was verified within the next 24 hours.

Uma mulher com 37 anos de idade, gestante de 35 semanas, foi admitida em um hospital local em razão de epistaxe grave, que resultou em choque e em necessidade de realização de cesárea emergencial. Após falha do tamponamento para controlar a hemorragia, decidiu-se por tratamento angiográfico. Após o procedimento, ela foi admitida à unidade de terapia intensiva neurocrítica, encontrando-se confusa e agitada, com necessidade de sedação e intubação orotraqueal. Na unidade de terapia intensiva, as investigações incluíram exames de ressonância magnética, punção lombar com painel viral, eletroencefalograma, testes para autoimunidade e avaliações hidroeletrolítica e metabólica. O exame de ressonância magnética mostrou área puntiforme restrita na corona radiata esquerda nas sequências de imagens pesadas em difusão, além de leve edema cortical posterior (sem restrição à difusão), e o eletroencefalograma mostrou atividade lenta difusa moderada, atividade frontoparietal lenta e escassos componentes paroxísticos associados no hemisfério esquerdo. Outros exames não mostraram alterações relevantes. Por causa da relação temporal e da história clínica, assim como imagens de ressonância magnética, formulou-se o diagnóstico de encefalopatia induzida por contraste. A sedação foi retirada após 2 dias na unidade de terapia intensiva, e a paciente foi extubada, verificando-se completa recuperação neurológica dentro das 24 horas seguintes.

Endovascular treatment of pediatric ischemic stroke: A single center experience and review of the literature.

INTRODUCTION: Mechanical thrombectomy is standard treatment for large vessel occlusion (LVO) in adults. There are no randomized controlled trials for the pediatric population. We report our single-center experience with thrombectomy of LVO in a series of pediatric patients, and perform a review of the literature. METHODS: Retrospective review of consecutive pediatric thrombectomy cases between 2011 and 2018. Demographic variables, imaging data, technical aspects and clinical outcome were recorded. RESULTS: In a period of 7 years, 7 children were treated for LVO at our center. Median age was 13 (2-17), and median Ped-NIHSS was 15 (3-24), and the median ASPECTS was 8 (2-10). Five patients had cardiac disease, and 2 of them were under external cardiac assistance. Median time from onset of symptoms to beginning of treatment was 7h06m (2h58m-21h38m). Five patients had middle cerebral artery occlusions. Thrombectomy was performed using a stentriever in 3 patients, aspiration in 3 patients, and combined technique in 1 patient. Six patients had good recanalization (TICI 2 b/3). There were no immediate periprocedural complications. At 3 months, 4 patients (57%) were independent (mRS score <3). Two patients died, one after haemorrhagic transformation of an extensive MCA infarct, and one due to extensive brainstem ischemia in the setting of varicella vasculitis. DISCUSSION: Selected pediatric patients with LVO may be treated with mechanical thrombectomy safely. In patients under external cardiac assistance and under anticoagulation, thrombectomy is the only alternative for treatment of LVO. A multidisciplinary approach in specialized pediatric stroke centers with trained neurointerventionalists are essential for good results.

Low prevalence of fetal-type posterior cerebral artery in patients with basilar tip aneurysms.

BACKGROUND: Basilar tip aneurysms (BTA) are multifactorial in origin, with luminal forces playing a major role in their formation. Considering the reduced hemodynamic stress on the basilar apex in the fetal-type posterior cerebral artery (fPCA), we hypothesize that BTA should be less common in patients with this variant. OBJECTIVE: To investigate, in a retrospective case-control study, the frequency of fPCA in patients with and without BTA. MATERIALS AND METHODS: We collected clinical and imaging data from consecutive patients with BTA undergoing catheter angiography between July 2010 and July 2015, and from a randomly selected, age- and sex-matched non-BTA control population from our prospective database. Anatomical variants of the distal basilar artery region were assessed in the two groups and compared using parametric and non-parametric tests. RESULTS: Fifty-nine BTA cases and 337 controls were included. fPCA was present in 3% of patients with BTA and 23% in the control group (p<0.001; OR=0.11, 95% CI 0.03 to 0.48). Basilar tip disposition was cranial in 49% of BTA and 63% of non-BTA cases (p=0.04; OR=0.57, 95% CI 0.33 to 0.99); a caudal disposition was found in 24% and 6% of cases, respectively (p<0.001; OR=4.65, 95% CI 2.21 to 9.80). CONCLUSIONS: We found a statistically significant association between the absence of fPCA and BTA. Our findings underline the importance of hemodynamic stress in the formation of intracranial aneurysms, and suggest that fPCA is a protective variant for formation of BTA.

Encefalopatia reversível induzida por contraste após embolização com espiras por epistaxe / Reversible contrast-induced encephalopathy after coil embolization of epistaxis

RESUMO Uma mulher com 37 anos de idade, gestante de 35 semanas, foi admitida em um hospital local em razão de epistaxe grave, que resultou em choque e em necessidade de realização de cesárea emergencial. Após falha do tamponamento para controlar a hemorragia, decidiu-se por tratamento angiográfico. Após o procedimento, ela foi admitida à unidade de terapia intensiva neurocrítica, encontrando-se confusa e agitada, com necessidade de sedação e intubação orotraqueal. Na unidade de terapia intensiva, as investigações incluíram exames de ressonância magnética, punção lombar com painel viral, eletroencefalograma, testes para autoimunidade e avaliações hidroeletrolítica e metabólica. O exame de ressonância magnética mostrou área puntiforme restrita na corona radiata esquerda nas sequências de imagens pesadas em difusão, além de leve edema cortical posterior (sem restrição à difusão), e o eletroencefalograma mostrou atividade lenta difusa moderada, atividade frontoparietal lenta e escassos componentes paroxísticos associados no hemisfério esquerdo. Outros exames não mostraram alterações relevantes. Por causa da relação temporal e da história clínica, assim como imagens de ressonância magnética, formulou-se o diagnóstico de encefalopatia induzida por contraste. A sedação foi retirada após 2 dias na unidade de terapia intensiva, e a paciente foi extubada, verificando-se completa recuperação neurológica dentro das 24 horas seguintes.

ABSTRACT A 37-year-old woman (35 weeks pregnant) was admitted to a local hospital due to severe epistaxis resulting in shock and the need for emergency cesarean section. After failure to tamponade the bleeding, angiographic treatment was provided. After the procedure, she was admitted to the neurocritical intensive care unit and was confused and agitated, requiring sedation and endotracheal intubation. In the intensive care unit, diagnostic investigations included brain magnetic resonance imaging, lumbar puncture with viral panel, electroencephalogram, tests for autoimmunity, and hydroelectrolytic and metabolic evaluations. Magnetic resonance imaging showed a puntiform restricted diffusion area on the left corona radiata on diffusion weighted imaging and mild cortical posterior edema (without restricted diffusion), and an electroencephalogram showed moderate diffuse slow activity and fronto-temporal slow activity of the left hemisphere with associated scarce paroxysmal components. The other exams did not show any relevant alterations. Due to the temporal relationship, the clinical history and the magnetic resonance imaging results, a diagnosis of contrast-induced encephalopathy was made. After 2 days in the intensive care unit, sedation was withdrawn, the patient was extubated, and total neurological recovery was verified within the next 24 hours.

A rare case of racemose neurocysticercosis and its complications. Case report.

Neurocysticercosis is a central nervous system infection caused by the pork tapeworm Taenia solium. The disease is endemic in Central and South America, Asia and Africa. Racemose neurocysticercosis refers to cysts in the subarachnoid space and is characterized by proliferative lobulated cysts without a scolex. We report a case of a 43-year-old woman with an eight-month history of headaches, ataxia and loss of vision. CT and MRI showed an intraventricular cyst, causing entrapment of Monro foramina and hydrocephalus, smaller cysts at subarachnoid space in temporal lobes, Sylvian fissures, supra-selar and perimesencephalic cisterns, and an intra-orbital cyst. Additionally, there were acute ischemic vascular lesions on the left thalamus and corpus callosum splenium and subacute ischemic lesions of both occipital lobes. The diagnosis of racemose cysticercosis was made after biopsy and drainage of the intraventricular cyst. It is important to recognize neurocysticercosis as a differential diagnosis in intra-cranial cysts, not only intraparenchymal cysts.

Bilateral panuveitis associated with Whipple disease - case report.

PURPOSE: To describe a clinical case and literature review of Whipple disease. METHODS: A 65-year-old male with bilateral decreased visual acuity for 3 weeks as well as bilateral hypoacusia, vertigo, disequilibrium, headache and decreased strength in the right upper limb for 4 months. The clinical work-up revealed a bilateral panuveitis and an ischemic cerebellar stroke. RESULT: The diagnosis of Whipple disease was confirmed by histopathological analysis of adenopathy. The patient was treated with cortico-antibiotic therapy with significant clinical improvement. CONCLUSION: Although rare, Whipple disease is potentially fatal if left untreated, it must be always be taken into consideration before any panuveitis of an unknown cause, even in the absence of gastrointestinal symptoms.