Interventional neuroradiology of stroke, still not dead

Since the National Institute of Neurological Disorders and Stroke trial,intravenous thrombolysis has been gaining wide acceptance as the modality of treatment for acute embolic stroke,with a current therapeutic window of up to 4.5 h.Both imaging[with either magnetic resonance imaging(MRI)or computed tomography(CT)]and interventional techniques(thrombolysis and/or thrombectomy)have since improved and provided us with additional imaging of the penumbra using CT or MRI and more advanced thrombolysis or thrombectomy strategies that have been embraced in many centers dealing with patients with acute cerebral ischemia.These techniques,however,have come under scrutiny due to their accrued healthcare costs and have been questioned following major recent studies.These studies basically showed that interventional techniques were not superior to the traditional intravenous thrombolysis techniques and that penumbra imaging could not determine what patients would benefit from more aggressive(i.e.,interventional)treatment.We discuss this in the light of the latest developments in both diagnostic and interventional neuroradiology and point out why further studies are needed in order to define the right choices for patients with acute stroke.Indeed,these studies were in part conducted with suboptimal patient recruitment strategies and did not always use the latest interventional techniques available today.So,while these studies may have raised some relevant questions,at the same time,definitive answers have not been given,in our opinion.

Acute coalescent mastoiditis in a 16-month-old child due to Streptococcus pneumoniae infection

Rationale:Acute otitis media is a common disease in early childhood,and is usually caused by Streptococcus pneumoniae(S.pneumoniae).Acute mastoiditis is a complication of acute otitis media and can involve not only the mucoperiosteum of the middle ear but can also spread to the periosteum by destroying the mastoid bone(acute coalescent mastoiditis).In addition,the infection can extend through the surrounding bones or the emissary veins beyond the mastoid’s air cells,leading to subperiosteal abscesses.Patient’s Concern:A 16-month-old female patient was hospitalized due to the purulent discharge of the left ear and the symptoms of right mastoiditis(swelling and redness of the skin).Diagnosis:Bilateral acute coalescent mastoiditis caused by S.pneumoniae infection.The computer tomography revealed bilateral bone destruction of the mastoid and abscesses found behind the auricle on both sides.Interventions:The patient underwent intravenous antibiotic therapy and surgical treatment.Outcomes:The patient was discharged 14 days after hospitalization with an improved condition.Lessons:Improperly treated acute coalescent mastoiditis can lead to extracranial and intracranial complications,sometimes serious and even life-threatening.Complications are prevalent in children under 2 years,in whom the disease progresses more rapidly and severely.The vaccination with a 13-valent vaccine may not result in sufficient immunity against S.pneumoniae,a predominant pathogen in children affected by acute coalescent mastoiditis.

Recurrent Transient Ischemic Attacks Revealing Cerebral Amyloid Angiopathy: A Comprehensive Case

This case report investigates the manifestation of cerebral amyloid angiopathy (CAA) through recurrent Transient Ischemic Attacks (TIAs) in an 82-year-old patient. Despite initial diagnostic complexities, cerebral angiography-MRI revealed features indicative of CAA. Symptomatic treatment resulted in improvement, but the patient later developed a fatal hematoma. The discussion navigates the intricate therapeutic landscape of repetitive TIAs in the elderly with cardiovascular risk factors, emphasizing the pivotal role of cerebral MRI and meticulous bleeding risk management. The conclusion stresses the importance of incorporating SWI sequences, specifically when suspecting a cardioembolic TIA, as a diagnostic measure to explore and exclude CAA in the differential diagnosis. This case report provides valuable insights into these challenges, highlighting the need to consider CAA in relevant cases.

Pseudoaneurysm formation following transarterial embolization of traumatic carotid-cavernous fistula with detachable balloon:An institutional cohort long-term study

BACKGROUND The goal of therapy for traumatic carotid-cavernous fistula(TCCF)is the elimination of fistula while maintaining patency of the parent artery.The treatment for TCCF has evolved from surgery to endovascular management using detachable balloons,coils,liquid embolic agents,covered stents,or flow-diverter stent through arterial or venous approaches.Despite the withdrawal of detachable balloons from the market in the United States since 2004,transarterial embolization with detachable balloons has currently remained the best initial treatment for TCCF in several countries.However,the pseudoaneurysm formation following transarterial detachable balloon embolization has rarely been observed in long-term follow-up.AIM To determine the occurrence and long-term follow-up of pseudoaneurysm after transarterial detachable balloon for TCCF.METHODS Between January 2009 and December 2019,79 patients diagnosed with TCCF were treated using detachable latex balloons(GOLDBAL)of four sizes.Pseudoaneurysm sizes were stratified into five grades for analysis.Initial and follow-up assessments involved computed tomography angiography at 1 month,6 month,1 year,and longer intervals for significant cases.Clinical follow-ups occurred semi-annually for 2 years,then annually.Factors analyzed included sex,age,fistula size and location,and balloon size.RESULTS In our cohort of 79 patients treated for TCCF,pseudoaneurysms formed in 67.1%,with classifications ranging from grade 0 to grade 3;no grade 4 or giant pseudoaneurysms were observed.The majority of pseudoaneurysms did not progress in size,and some regressed spontaneously.Calcifications developed in most large pseudoaneurysms over 5-10 years.Parent artery occlusion occurred in 7.6%and recurrent fistulas in 16.5%.The primary risk factors for pseudoaneurysm formation were identified as the use of specific balloon sizes,with balloon SP and No.6 significantly associated with its occurrence(P=0.005 and P=0.002,respectively),whereas sex,age,fistula size,location,and the number of balloons used were not significant predictors.CONCLUSION Pseudoaneurysm formation following detachable balloon embolization for TCCF is common,primarily influenced by the size of the balloon used.Despite this,all patients with pseudoaneurysms remained asymptomatic during long-term follow-up.

From strength to precision: A systematic review exploring the clinical utility of 7-Tesla magnetic resonance imaging in abdominal imaging

BACKGROUND After approval for clinical use in 2017 early investigations of ultra-high-field abdominal magnetic resonance imaging(MRI)have demonstrated the feasibility as well as diagnostic capabilities of liver,kidney,and prostate MRI at 7-Tesla.However,the elevation of the field strength to 7-Tesla not only brought advantages to abdominal MRI but also presented considerable challenges and drawbacks,primarily stemming from heightened artifacts and limitations in Specific Absorption Rate,etc.Furthermore,evidence in the literature is relatively scarce concerning human studies in comparison to phantom/animal studies which necessitates an investigation into the evidence so far in humans and summarizing all relevant evidence.AIM To offer a comprehensive overview of current literature on clinical abdominal 7T MRI that emphasizes current trends,details relevant challenges,and provides a concise set of potential solutions.METHODS This systematic review adheres to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.A PubMed search,utilizing Medical Subject Headings terms such as"7-Tesla"and organ-specific terms,was conducted for articles published between January 1,1985,and July 25,2023.Eligibility criteria included studies exploring 7T MRI for imaging human abdominal organs,encompassing various study types(in-vivo/ex-vivo,method development,reviews/meta-analyses).Exclusion criteria involved animal studies and those lacking extractable data.Study selection involved initial identification via title/abstract,followed by a full-text review by two researchers,with discrepancies resolved through discussion.Data extraction covered publication details,study design,population,sample size,7T MRI protocol,image characteristics,endpoints,and conclusions.RESULTS The systematic review included a total of 21 studies.The distribution of clinical 7T abdominal imaging studies revealed a predominant focus on the prostate(n=8),followed by the kidney(n=6)and the hepatobiliary system(n=5).Studies on these organs,and in the pancreas,demonstrated clear advantages at 7T.However,small bowel studies showed no significant improvements compared to traditional MRI at 1.5T.The majority of studies evaluated originated from Germany(n=10),followed by the Netherlands(n=5),the United States(n=5),Austria(n=2),the United Kingdom(n=1),and Italy(n=1).CONCLUSION Further increase of abdominal clinical MRI field strength to 7T demonstrated high imaging potential,yet also limitations mainly due to the inhomogeneous radiofrequency(RF)excitation field relative to lower field strengths.Hence,further optimization of dedicated RF coil elements and pulse sequences are expected to better optimize clinical imaging at high magnetic field strength.

Potential applications of 7 Tesla magnetic resonance imaging in paediatric neuroimaging:Feasibility and challenges

The integration of 7 Tesla magnetic resonance imaging(7 T MRI)in adult patients has marked a revolutionary stride in radiology.In this article we explore the feasibility of 7 T MRI in paediatric practice,emphasizing its feasibility,applications,challenges,and safety considerations.The heightened resolution and tissue contrast of 7 T MRI offer unprecedented diagnostic accuracy,particularly in neuroimaging.Applications range from neuro-oncology to neonatal brain imaging,showcasing its efficacy in detecting subtle structural abnormalities and providing enhanced insights into neurological conditions.Despite the promise,challenges such as high cost,discomfort,and safety concerns necessitate careful consideration.Research suggests that,with precautions,7 T MRI is feasible in paediatrics,yet ongoing studies and safety assessments are imperative.

Intracochlear schwannoma: Imaging diagnosis

Intralabyrinthine schwannomas(ILS)are rare benign tumors,often responsible for hearing loss.MRI is important in establishing the diagnosis.We present the example of a 48-year-old lady who reported a 3-years history of right-sided sensorineural deafness.MRI demonstrated a loss of the normal hypersignal of the second turn of the right cochlea compatible with intracochlear schwannoma.

Acute isolated vertigo with vertical up-beating nystagmus: A rare case of nucleus intercalatus of Staderini ischemia

The role of intercalatus nucleus of Staderini(INS),the most caudal of the perihypoglossal nuclei,is much debated.Last research seems to suggest that this nucleus plays a role as a vertical eyes movements integrator.The few clinical reports present in the literature that describe isolated lesions of the INS have described patients presenting in acute with up-beating vertical spontaneous nystagmus.Isolated acute lesion of INS is,in fact,much rare,and,without other neurological signs,is exceptional.We present a case of acute isolated vertigo with no other neurological signs or symptoms,due to INS ischemia provoked by vertebral artery stenosis.The patient presented with spontaneous vertical up-beating nystagmus that showed at videonystagmographic recording,a clear exponential decay of angular slow-phase velocity,that is considered a typical sign of neural integrator impairment.This case seems to represent a further confirm that INS is part,as a vertical-to-position neural integrator,of the neural circuit controlling the vertical eyes movements.

Choroid plexus imaging to track neuroinflammation—a translational model for mouse and human studies

The choroid plexus(ChP)is a highly vascularized and secretory tissue in each of the brain ventricles that represents the key structure between the blood and the cerebrospinal fluid(CSF).Besides its essential role in CSF production and brain waste clearance pathways,the ChP also contributes to the regulation of central nervous system(CNS)immunosurveillance(Ghersi-Egea et al.,2018).Indeed,the ChP forming the blood-CSF barrier(BCSFB)regulates the entry of immune cells and solute molecules into the brain and vice versa.When antigen-specific,autoreactive immune activation occurs in the periphery,inflammatory cells migrate through the brain barriers towards the CNS(Strominger et al.,2018),initiating neuroinflammatory diseases such as multiple sclerosis(MS).

Challenges and limitations of synthetic minority oversampling techniques in machine learning

Oversampling is the most utilized approach to deal with class-imbalanced datasets,as seen by the plethora of oversampling methods developed in the last two decades.We argue in the following editorial the issues with oversampling that stem from the possibility of overfitting and the generation of synthetic cases that might not accurately represent the minority class.These limitations should be considered when using oversampling techniques.We also propose several alternate strategies for dealing with imbalanced data,as well as a future work perspective.

Stent-assisted coiling of intracranial carotid ophthalmic segment aneurysm segment aneurysms:Long-term follow-up from a single center

Background:To evaluate the efficacy of stent-assisted coiling(SAC)for the treatment of carotid ophthalmic segment aneurysm segment aneurysms(OSAs)of the internal carotid artery(ICA)through detailed long-term follow-up of a large patient cohort.Methods:We retrospectively analyzed 88 consecutive patients with OSAs between January 2009 and January 2020 at our center.Angiographic results were evaluated using the modified Raymond grading system and clinical outcomes were evaluated using the mRS scale.The primary endpoints were major aneurysm recurrence and poor clinical outcomes for at least 18 months of follow-up.The patients were asked to attend clinical follow-up assessments and possibly undergo DSA or MR via telephone.Results:We enrolled 88 patients with 99 OSAs treated with coiling,of whom 76 were treated with SAC.The coiling procedures were successful in all 88 patients.Overall,complications occurred in 8 patients(9.1%).No procedure-related mortality was observed.67(76.1%)experienced immediate aneurysm occlusion at the end of the procedure.Long-term angiographic follow-up(18 months)was available in 45/88 aneurysms(51%)(average 18.7±5.2 months).Four patients continued their follow-up for 5 years after initial aneurysm treatment.After a clinical follow-up time of 28.7 months(range,12-51 months),85 patients(95.5%)achieved favorable clinical outcomes(mRS scores of 0-2).Conclusions:This study indicates that SAC treatment is a safe and effective therapeutic alternative for ruptured and unruptured OSAs.The procedural risks are low with relatively long-term effectiveness.

动脉瘤性蛛网膜下腔出血患者在血管内弹簧圈治疗中动脉瘤破裂的原因、处理和预后

目的探讨动脉瘤性蛛网膜下腔出血(SAH)患者在血管内弹簧圈治疗中动脉瘤被穿破的原因、处理和预后。方法回顾性研究1992～2003年在弗莱堡大学医院神经中心的202例急性动脉瘤性SAH接受血管内弹簧圈介入治疗患者,系统研究病例记录和由2名神经放射科医生重新阅片。结果6例患者发生介入术中动脉瘤被穿破,男1例,女5例,年龄33～87岁。5例囊性动脉瘤,1例右颈内动脉夹层动脉瘤。4例被弹簧圈穿破,1例被微导丝穿破,1例被微导管穿破。4例临床预后好,出院时没有新的神经功能缺损(mRS0分和2分各2例),1例临床状况无改变(治疗前H&HV级,出院时mRS5分),1例死于严重的SAH(治疗前H&HV级)。结论在动脉瘤性SAH患者的血管内弹簧圈治疗中,总的术中穿破率为3%,死亡率为0.5%;造影剂外渗或弹簧圈的头端突出动脉瘤外提示术中动脉瘤被穿破,发生穿破后应尽可能快的用弹簧圈封堵动脉瘤的破裂部位;患者的预后可能与治疗前病情轻重直接相关。

多发性硬化早期胼胝体的DTI改变

目的:探讨多发性硬化(MS)早期常规MR扫描表现正常的胼胝体的磁共振弥散张量成像(DTI)的改变。方法:20例病程相对较短(平均2.3年)的MS患者和20个年龄性别相匹配的健康志愿者为对照进行MR扫描,获取高分辨常规MRI(T1WI、T2WI、FLAIR)图像及DTI图像,获得表现正常胼胝体(NACC)和额、枕部表现正常白质(NAWM)的部分各向异性指数(FA)值和平均扩散系数(MD)值。结果:早期MS患者的NACC与正常对照比较,其FA值显著下降(P<0.001)、MD值显著增加(P<0.001);早期MS患者额、枕部的NAWM和正常对照比较,其FA值(P=0.216)、MD值(P=0.673)差异均无统计学意义。NACC的平均MD值和反映脑实质中央性萎缩的Evans指数间存在相关性(r=0.648,P=0.043)。结论:定量磁共振弥散张量值(FA值和MD值)的变化表明MS疾病早期损害优先出现在胼胝体,胼胝体的结构特点可能是其在MS早期易受损害的重要原因。定量DTI可用于监控和评估早期MS患者NACC的改变和预后。

磁共振弥散张量成像定量分析复发-缓解型多发性硬化患者表现正常的脑干白质纤维束

目的应用磁共振弥散张量成像(DTI)定量分析复发-缓解型多发性硬化(RRMS)患者表现正常的脑干白质纤维束的改变。方法对50例RRMS患者(RRMS组)及25名年龄和性别相匹配的健康志愿者(对照组)行磁共振扫描,获取常规MR图像和DTI图像。比较两组脑干主要纤维束(皮质脊髓束/皮质脑桥束、小脑上、中、下脚纤维束和内侧丘系纤维束)的部分各向异性分数(FA)和平均弥散系数(MD)的变化。结果排除年龄、性别等因素影响后,经ANCOVA协方差分析,RRMS组患者皮质脊髓束/皮质脑桥束(L:P=0.030;R:P=0.020)、小脑下脚(L:P=0.030;R:P=0.037)、小脑上脚(L:P=0.036;R:P=0.041)、内侧丘系(L:P=0.014;R:P=0.035)的FA值较对照组明显降低。RRMS组患者皮质脊髓束/皮质脑桥束(L:P=0.004;R:P=0.046)、小脑下脚(L:P=0.047;R:P=0.011)、小脑上脚(L:P=0.021;R:P=0.011)、内侧丘系(L:P=0.002;R:P=0.044)的MD值较对照组明显增高。小脑中脚的MD值及FA值两组间差异均无统计学意义(P>0.05)。RRMS患者表现正常脑干白质纤维束的MD值及FA值与脑实质分数(BPF)、T2病灶容积之间均无相关性。结论RRMS患者表现正常脑干白质纤维束DTI的异常发现,提示上述纤维束存在微观病变,推测病变可能是局部隐匿性病灶导致的髓鞘脱失、轴突破坏。

Magnetic resonance imaging differential diagnosis of brainstem lesions in children

Differential diagnosis of brainstem lesions,either isolated or in association with cerebellar and supra-tentorial lesions,can be challenging. Knowledge of the structural organization is crucial for the differential diagnosis and establishment of prognosis of pathologies with involvement of the brainstem. Familiarity with the location of the lesions in the brainstem is essential,especially in the pediatric population. Magnetic resonance imaging(MRI) is the most sensitive and specific imaging technique for diagnosing disorders of the posterior fossa and,particularly,the brainstem. High magnetic static field MRI allows detailed visualization of the morphology,signal intensity and metabolic content of the brainstem nuclei,together with visualization of the normal development and myelination. In this pictorial essay we review the brainstem pathology in pediatric patients and consider the MR imaging patterns that may help the radiologist to differentiate among vascular,toxico-metabolic,infectiveinflammatory,degenerative and neoplastic processes. Helpful MR tips can guide the differential diagnosis: These include the location and morphology of lesions,the brainstem vascularization territories,gray and white matter distribution and tissue selective vulnerability.

复发-缓解型多发性硬化投射纤维束定量DTI

目的:探讨复发-缓解型多发性硬化(RRMS)患者投射纤维定量扩散张量改变。方法:20例RRMS患者及年龄和性别相匹配的20例健康志愿者(对照组)行MRI扫描,获取常规MRI及DTI图像,分别进行测量分析,比较2组投射纤维的部分各向异性指数(FA)和平均扩散系数(MD)值的变化。主要纤维束包括丘脑前辐射(atr)、丘脑上辐射(str)、丘脑后辐射(ptr)、皮质延髓束(cpt)、皮质脊髓束(cst)等。结果:RRMS组患者与健康对照组的FA值比较:ptr(左侧:0.541±0.141 vs 0.628±0.153;右侧:0.512±0.079 vs 0.560±0.102)、cpt/atr(左侧:0.421±0.118 vs 0.503±0.104;右侧:0.437±0.064 vs 0.512±0.102)、cpt/ptr(左侧:0.405±0.056 vs 0.500±0.078;右侧:0.427±0.057 vs 0.496±0.083)、cpt/cst/str(左侧:0.476±0.115 vs 0.554±0.056;右侧:0.462±0.095 vs 0.520±0.074),RRMS组的FA值均较健康对照组低,2组间差异有统计学意义(P<0.05);RRMS组患者atr的FA值(左侧:0.538±0.103,右侧:0.542±0.092)与对照组(左侧:0.564±0.087;右侧0.568±0.116)比较,差异无统计学意义(P>0.05)。RRMS组患者与健康对照组的MD值比较:cpt/ptr(左侧:0.928±0.102 vs 0.853±0.105;右侧:0.949±0.165 vs 0.859±0.141)、cpt/cst/str(左侧:0.811±0.137 vs 0.772±0.093;右侧:0.868±0.167 vs 0.784±0.128)的MD值差异有统计学意义(P<0.05),RRMS组的MD值较健康对照组增高;RRMS组患者atr(左侧:0.898±0.143 vs 0.868±0.118;右侧:0.850±0.164 vs0.835±0.074)、ptr(左侧:0.874±0.203 vs 0.829±0.103;右侧:0.847±0.172 vs 0.802±0.075)、cpt/atr(左侧:0.856±0.187 vs 0.805±0.161;右侧:0.829±0.246 vs 0.820±0.093)的MD值和健康对照比较差异均无统计学意义(P>0.05)。结论:多发性硬化患者双侧ptr、cpt/atr、cpt/ptr、cpt/cst/str存在FA值减小,双侧cpt/ptr、cpt/cst/str存在MD值的增高,提示在投射纤维中上述白质纤维束存在结构改变,DTI可以作为反映RRMS投射纤维微观病理改变的敏感检查指标。

Nitinol Stenting in Post-Traumatic Pseudo-Aneurysm of Internal Carotid Artery

Background: A pseudoaneurysm of the internal carotid artery (ICA) at its cervicl part, is a rare and often lethal com-plication after cervical trauma. The treatment of choice is anticoagulation. Patients with a contraindication for anticoagulation or those who do not improve with standard treatment, warrant either a surgical repair or stent placement.Stent placement posses both short and long term risks such as immediate ischemic events, in-stent stenosis and stent breakage, thus the choice of stent type is critical. Advances in stent technology have made cervical stent placement a viable option. We report our experience with the LEO + (Balt Extrusion, Montmorency, France) nitinol flexible self expanding stent for post-traumatic ICA aneurysms. Methods: 5 patients suffering a post-traumatic cervical ICA pseudo-aneurysms refractory to standard treatment were treated with nitinol braided flexible self expanding stent. This stent has a shape memory and superelasticity virtues making it suitable. Diagnosis was made with CT angiography and confirmed by catheter angiography. All procedures were preformed under local anesthesia. Time between trauma and treatment ranged six days to over five years. Follow-up was performed by CT angiography or conventional angiography. Results: Five patients, having eight aneurysms were treated using 12 stents. In all cases, appropriate stent placement was achieved. No immediate or late complications, as well as no neurological sequele reported at 6 months. Radiological follow-up exams demonstrated complete pseudoaneurysm closure. Conclusion: Stent placement can be a safe and definitive treatment option for patients to conventional medical treatment.

Susceptibility weighted imaging: Clinical applications and future directions

Susceptibility weighted imaging(SWI) is a recently developed magnetic resonance imaging(MRI) technique that is increasingly being used to narrow the differential diagnosis of many neurologic disorders. It exploits the magnetic susceptibility differences of various compounds including deoxygenated blood, blood products, iron and calcium, thus enabling a new source of contrast in MR. In this review, we illustrate its basic clinical applications in neuroimaging. SWI is based on a fully velocity-compensated, high-resolution, three dimensional gradientecho sequence using magnitude and phase images either separately or in combination with each other, in order to characterize brain tissue. SWI is particularly useful in the setting of trauma and acute neurologic presentations suggestive of stroke, but can also characterize occult low-flow vascular malformations, cerebral microbleeds, intracranial calcifications, neurodegenerative diseases and brain tumors. Furthermore, advanced MRI post-processing technique with quantitative susceptibility mapping, enables detailed anatomical differentiation based on quantification of brain iron from SWI raw data.