Primary angiitis of the central nervous system at conventional angiography

Subarachnoid Hemorrhaging with Multiple Cerebral Artery Stenoses after Initiating Remission Induction Therapy for Eosinophilic Granulomatosis with Polyangiitis

We encountered a 64-year-old Japanese woman who developed subarachnoid hemorrhaging (SAH) with multiple cerebral artery stenoses during remission induction therapy for eosinophilic granulomatosis and polyangiitis (EGPA). The treatment involved intensified steroid pulse therapy and continued intravenous cyclophosphamide pulse therapy, which led to beneficial effects. Given the rarity of multiple EGPA-associated cerebral artery stenoses and SAH, it is crucial to differentiate them from other diseases. The mortality rate of EGPA complicated by intracranial hemorrhagic lesions, including SAH, is high. When headache is present at the onset of EGPA, the possibility of SAH must be considered.

The role of susceptibility-weighted imaging & contrast-enhanced MRI in the diagnosis of primary CNS vasculitis: a large case series

Primary CNS Vasculitis (PCNSV) is a rare, diverse, and polymorphic CNS blood vessel inflammatory condition. Due to its rarity, clinical variability, heterogeneous imaging results, and lack of definitive laboratory markers, PCNSV diagnosis is challenging. This retrospective cohort analysis identified patients with histological diagnosis of PCNSV. Demographic data, clinical presentation, neuroimaging studies, and histopathologic findings were recorded. We enrolled 56 patients with a positive biopsy of CNS vasculitis. Most patients had cerebral hemisphere or brainstem symptoms. Most brain MRI lesions were bilateral, diffuse discrete to confluent white matter lesions. Frontal lobe lesions predominated, followed by inferior cerebellar lesions. Susceptibility-weighted imaging (SWI) hemorrhages in 96.4% (54/56) of patients, either solitary microhemorrhages or a combination of micro and macrohemorrhages. Contrast-enhanced T1-WIs revealed parenchymal enhancement in 96.3% (52/54 patients). The most prevalent pattern of enhancement observed was dot-linear (87%), followed by nodular (61.1%), perivascular (25.9%), and patchy (16.7%). Venulitis was found in 19 of 20 individuals in cerebral DSA. Hemorrhages in SWI and dot-linear enhancement pattern should be incorporated as MINOR diagnostic criteria to diagnose PCNSV accurately within an appropriate clinical context. Microhemorrhages in SWI and venulitis in DSA, should be regarded as a potential marker for PCNSV.

Pathology of Primary Angiitis of the Central Nervous System

Primary angiitis of the central nervous system (PACNS) is a rare and potentially severe form of vasculitis that is limited to the brain, spinal cord, and meninges. Despite extensive research, the etiology and underlying immunologic mechanisms of PACNS remain largely unknown. PACNS presents with a variety of clinical, radiological, and pathologic features, but it is generally characterized by inflammation and destruction of the walls of blood vessels in the CNS, which can lead to tissue ischemia and/or hemorrhage. Three main histopathologic patterns have been identified, namely granulomatous, lymphocytic, and necrotizing vasculitis.

European Stroke Organisation (ESO) guidelines on Primary Angiitis of the Central Nervous System (PACNS)

The European Stroke Organisation (ESO) guideline on Primary Angiitis of the Central Nervous System (PACNS), developed according to ESO standard operating procedures (SOP) and Grading of Recommendations, Assessment, Development and Evaluation (GRADE) methodology, was elaborated to assist clinicians in the diagnostic and treatment pathway of patients with PACNS in their decision making. A working group involving vascular neurologists, neuroradiologists, rheumatologists, a neuropathologist and a methodologist identified 17 relevant clinical questions; these were addressed according to the patient/population, intervention, comparison and outcomes (PICO) framework and systematic literature reviews were performed. Notably, each PICO was addressed with respect to large vessel (LV)-PACNS and small vessel (SV)-PACNS. Data to answer many questions were scarce or lacking and the quality of evidence was very low overall, so, for some PICOs, the recommendations reflect the ongoing uncertainty. When the absence of sufficient evidence precluded recommendations, Expert Consensus Statements were formulated. In some cases, this applied to interventions in the diagnosis and treatment of PACNS which are embedded widely in clinical practice, for example patterns of cerebrospinal fluid (CSF) and Magnetic Resonance Imaging (MRI) abnormalities. CSF analysis for hyperproteinorrachia and pleocytosis does not have evidence supporting their use as diagnostic tools. The working group recommended that caution is employed in the interpretation of non-invasive vascular imaging due to lack of validation and the different sensitivities in comparison with digital subtraction angiography (DSA) and histopathological analyses. Moreover, there is not a neuroimaging pattern specific for PACNS and neurovascular issues are largely underreported in PACNS patients. The group's recommendations on induction and maintenance of treatment and for primary or secondary prevention of vascular events also reflect uncertainty due to lack of evidence. Being uncertain the role and practical usefulness of current diagnostic criteria and being not comparable the main treatment strategies, it is suggested to have a multidisciplinary team approach in an expert center during both work up and management of patients with suspected PACNS. Highlighting the limitations of the currently accepted diagnostic criteria, we hope to facilitate the design of multicenter, prospective clinical studies and trials. A standardization of neuroimaging techniques and reporting to improve the level of evidence underpinning interventions employed in the diagnosis and management of PACNS. We anticipate that this guideline, the first comprehensive European guideline on PACNS management using GRADE methodology, will assist clinicians to choose the most effective management strategy for PACNS.

Why Would a Child Have a Stroke?

Identifying the etiology of childhood arterial ischemic stroke helps prevent stroke recurrence. In addition, stroke may herald a serious underlying condition requiring treatment, such as acquired heart disease, malignancy, or autoimmune disorder. Evidence-based guidelines exist for adults to identify and treat common risk factors for primary and secondary stroke, including hypertension, diabetes, elevated lipids, atrial fibrillation, and sleep apnea, which are rarely relevant in children. However, guidelines do not exist in pediatrics. Identifying the cause of childhood stroke may be straightforward or may require extensive clinical and neuroimaging expertise, serial evaluations, and reassessment based on the evolving clinical picture. Risk factors may be present but not necessarily causative, or not causative until a triggering event such as infection or anemia occurs. Herein, we describe strategies to determine stroke etiology, including challenges and potential pitfalls.

Primary angiitis of the central nervous system and reversible cerebral vasoconstriction syndrome: analysis of the National Inpatient Sample

INTRODUCTION

Primary angiitis of the central nervous system (PACNS) and reversible cerebral vasoconstriction syndrome (RCVS) are two rare syndromes that affect the cerebral vasculature. Both conditions have been shown to cause severe neurologic complications. Distinguishing these two conditions in clinical practice is often challenging. Here, we compare the clinical features and outcomes of RCVS and PACNS hospitalizations against the general adult inpatient population.

MATERIALS AND METHODS

We conducted a retrospective review of hospitalizations with a diagnosis of PACNS or RCVS from 2016 to 2018 in the National Inpatient Sample (NIS) database. Multivariate analysis was performed to calculate adjusted odds ratios (OR_adj) for hospital outcomes.

RESULTS

In the NIS, 3305 hospitalizations had a diagnosis of RCVS and 6035 hospitalizations had a diagnosis of PACNS. RCVS hospitalizations had a significantly greater association with cerebral aneurysms (OR_adj 23.80), hemiplegia/hemiparesis following subarachnoid hemorrhage (SAH) (OR_adj 324.09), ischemic stroke (OR_adj 7.59), and nontraumatic SAH (OR_adj 253.61). PACNS hospitalizations had a significantly greater association with hemiplegia/hemiparesis following cerebrovascular accident (CVA) (OR_adj 6.16), ischemic stroke (OR_adj 11.55), nontraumatic SAH (OR_adj 7.29), seizure (OR_adj 2.49), and in-hospital mortality (OR_adj 2.85).

CONCLUSIONS

We performed an analysis of the NIS to better understand RCVS and PACNS hospitalizations. Severe neurologic events including CVA and SAH were elevated in both, but SAH and related hemiplegia/hemiparesis were extremely common among RCVS hospitalizations. In-hospital mortality was elevated in PACNS but not RCVS. This information can be used to help clinicians better understand, distinguish, and diagnose these conditions. Key Points • Despite clear description of RCVS and PACNS in the medical literature, there remains a scarcity of national population-based studies comparing these two entities against the general adult inpatient population. • This study aims to fill knowledge gaps in this area. • Here, we compare the clinical features and outcomes of RCVS and PACNS hospitalizations against the general adult inpatient population.

Challenging presentation of primary vasculitis of the central nervous system

OBJECTIVE

To show a patient with a diagnosis of primary vasculitis of the nervous system and review this entity's literature.

CLINICAL CASE

Male 32 years, with two events; first, with a transient monoparesis of the right upper extremity, improve with steroids in days. Now, with a motor Jacksonian progression from the upper to the lower right extremities and generalized seizures. After; aphasia, right hemiparesis, and delirium. In the antiresonance, the finding of multiple arterial cerebral "beading." With an in-depth study, the diagnosis of primary cerebral vasculitis was made. The management with levetiracetam, steroids, and Azathioprine offers a satisfactory evolution.

DISCUSSION

The primary CNS vasculitis is an exclusion diagnosis, with angio-MRI is possible to suspect it, but it is always obligate to discard a secondary etiology by infection, systemic diseases, neoplasia, and drugs.

CONCLUSION

Although this problem is infrequent, we must consider this possibility. Opportune treatment can restore the quality of life.

Diagnosis and follow-up evaluation of central nervous system vasculitis: an evaluation of vessel-wall MRI findings

Objective

To approach the clinical value of MRI with vessel wall imaging (VWI) in patients with central nervous system vasculitis (CNSV), we analyzed patterns of VWI findings both at the time of initial presentation and during follow-up.

Methods

Stenoocclusive lesions, vessel-wall contrast enhancement (VW-CE) and diffusion-restricted lesions were analyzed in patients with a diagnosis of CNSV. On available VWI follow-up, progression, regression or stability of VW-CE were evaluated and correlated with the clinical status.

Results

Of the 45 patients included, 28 exhibited stenoses visible on MR angiography (MRA-positive) while 17 had no stenosis (MRA-negative). VW-CE was found in 2/17 MRA-negative and all MRA-positive patients (p < 0.05). 79.1% (53/67) of stenoses showed VW-CE. VW-CE was concentric in 88.3% and eccentric in 11.7% of cases. Diffusion-restricted lesions were found more frequently in relation to stenoses with VW-CE than without VW-CE (p < 0.05). 48 VW-CE lesions in 23 patients were followed over a median time of 239.5 days. 13 VW-CE lesions (27.1%) resolved completely, 14 (29.2%) showed partial regression, 17 (35.4%) remained stable and 4 (8.3%) progressed. 22/23 patients received immunosuppressive therapy for the duration of follow-up. Patients with stable or progressive VW-CE were more likely (p < 0.05) to have a relapse (14/30 cases) than patients with partial or complete regression of VW-CE (5/25 cases).

Conclusion

Concentric VW-CE is a common finding in medium/large-sized vessel CNSV. VW-CE might represent active inflammation in certain situations. However, follow-up VWI findings proved ambiguous as persisting VW-CE despite immunosuppressive therapy and clinical remission was a frequent finding.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00415-021-10683-7.

Quantifying Intra-Arterial Verapamil Response as a Diagnostic Tool for Reversible Cerebral Vasoconstriction Syndrome

BACKGROUND AND PURPOSE

There is mounting evidence supporting the benefit of intra-arterial administration of vasodilators in diagnosing reversible cerebral vasoconstriction syndrome. We prospectively quantified the degree of luminal diameter dilation after intra-arterial administration of verapamil and its accuracy in diagnosing reversible cerebral vasoconstriction syndrome.

MATERIALS AND METHODS

Patients suspected of having intracranial arteriopathy on noninvasive imaging and referred for digital subtraction angiography were enrolled in a prospective registry. Intra-arterial verapamil was administered in vascular territories with segmental irregularities. The caliber difference (Caliber_post - Caliber_pre) and the proportion of caliber change ([(Caliber_post - Caliber_pre)/Caliber_pre] × 100%) were used to determine the response to verapamil. The diagnosis of reversible cerebral vasoconstriction syndrome was made on the basis of clinical and imaging features at a follow-up appointment, independent of the reversibility of verapamil. Receiver operating characteristic curve analysis was performed to determine the best threshold.

RESULTS

Twenty-six patients were included, and 9 (34.6%) were diagnosed with reversible cerebral vasoconstriction syndrome. A total of 213 vascular segments were assessed on diagnostic angiography. Every patient with a final diagnosis of reversible cerebral vasoconstriction syndrome responded to intra-arterial verapamil. The maximal proportion of change (P < .001), mean proportion of change (P = .002), maximal caliber difference (P = .004), and mean caliber difference (P = .001) were statistically different between patients with reversible cerebral vasoconstriction syndrome and other vasculopathies. A maximal proportion of change  ≥32% showed a sensitivity of 100% and a specificity of 88.2% to detect reversible cerebral vasoconstriction syndrome (area under the curve = 0.951). The Reversible Cerebral Vasoconstriction Syndrome-2 score of  ≥5 points achieved a lower area under the curve (0.908), with a sensitivity of 77.8% and a specificity of 94.1%.

CONCLUSIONS

Objective measurement of the change in the arterial calibers after intra-arterial verapamil is accurate in distinguishing reversible cerebral vasoconstriction syndrome from other vasculopathies. A proportion of change  ≥32% has the best diagnostic performance.

Primary Angiitis of the Central Nervous System Presenting as a Cerebral Mass Lesion: A Case Report and Literature Review

Primary angiitis of the central nervous system (PACNS) is a rare form of vasculitis and is confined entirely to the central nervous system (CNS)without systemic involvement. We report a rare case of PACNS in a 39-year-old female with new onset seizures and a right frontal enhancing mass. Initially the patient was thought to have a high-grade glioma and thus underwent a right frontal craniotomy for resection of right frontal mass. Intraoperatively, two fresh tissue samples were sent for intraoperative consultation. Sample 1 showed predominantly necrotic tissue and scant glial cells while sample 2 revealed glial tissue favoring gliosis versus low-grade neoplasm with necrosis and a few acute inflammatory cells. Final pathological diagnosis was consistent with PACNS. Postoperatively, the patient recovered well from surgery with no neurological deficits and was discharged on postoperative day 3. Two weeks after surgery the patient was started on cyclophosphamide and prednisone by Rheumatology. At one month follow up, the patient remained asymptomatic and seizure free.

Intra-Arterial Verapamil Treatment in Oral Therapy-Refractory Reversible Cerebral Vasoconstriction Syndrome

Reversible vasoconstriction syndrome is a complex of clinical symptoms and angiographic findings, which, while having a mostly benign clinical course, has clinical and imaging overlap with more serious disorders such as vasculitis and aneurysmal SAH and itself includes a minority of patients with fulminant vasoconstriction resulting in severe intracranial complications. Endovascular options for patients with refractory reversible cerebral vasoconstriction syndrome include intra-arterial vasodilator infusion similar to therapy for patients with vasospasm after SAH. To date, only case reports and 1 small series have discussed the utility of intra-arterial vasodilators for the treatment of reversible cerebral vasoconstriction syndrome. We report an additional series of 11 medically refractory cases of presumed or proved reversible cerebral vasoconstriction syndrome successfully treated with intra-arterial verapamil infusion. Furthermore, we propose that the reversal of vasoconstriction, as seen on angiography, could fulfill a diagnostic criterion.

The diagnosis of primary central nervous system vasculitis

The diagnosis of primary central nervous system (CNS) vasculitis is often difficult. There are neither specific clinical features nor a classical clinical course, and no blood or imaging investigations that can confirm the diagnosis. Contrast catheter cerebral angiography is neither specific nor sensitive, yet still underpins the diagnosis in many published studies. Here we describe an approach to its diagnosis, emphasising the importance of obtaining tissue, and present for discussion a new, binary set of diagnostic criteria, dividing cases into only ‘definite’ primary CNS vasculitis, where tissue proof is available, and ‘possible,’ where it is not. We hope that these criteria will be modified and improved by discussion among experts, and that these (improved) criteria may then be adopted and used as the basis for future prospective studies of the clinical features and diagnosis of this difficult and dangerous disorder, particularly for coordinated multicentre therapeutic trials.

Concordance of angiography and cerebral biopsy results for suspected primary central nervous system vasculitis: A multi-center retrospective review

OBJECTIVE

Primary CNS Vasculitis (PCNSV) is a rare disease that is often challenging to diagnose. Cerebral angiography and biopsy have been utilized in the diagnostic workup for several decades but limited literature reports on the concordance of findings of angiography and biopsy. The primary objective of this work was to examine how cerebral angiography corresponded with biopsy findings in patients with suspected PCNSV.

PATIENTS AND METHODS

A total of 128 patients who underwent workup for PCNSV between years 2005-2016 were identified by query of existing neurological surgery and angiography databases at University Hospitals Cleveland Medical Center (UHCMC) and the Cleveland Clinic Foundation (CCF). The primary outcome was to examine the concordance of results between angiography and cerebral biopsy. Secondary outcomes included examining concordance between results of biopsy and other commonly performed tests for diagnosis of PCNSV including Magnetic Resonance Imaging (MRI), cerebrospinal fluid white blood cell count (CSF WBC), Erythrocyte Sedimentation Rate (ESR), C-reactive protein (CRP).

RESULTS

128 patients underwent cerebral biopsy for diagnosis of suspected PCNSV. 93 (73%) of these patients also underwent angiography. Of the 34 patients with positive biopsy findings, only 5 also had positive angiography. Positive angiography was not found to be correlated with positive biopsy in our analysis. The only test that was significantly associated with biopsy proven vasculitis was increased CSF WBC count (P = 0.0114).

CONCLUSIONS

PCNSV is a rare disease and often requires multiple tests or procedures to obtain definitive diagnosis. These results suggest that cerebral angiography findings are not associated with biopsy findings and should be used cautiously in the diagnostic work-up of PCNSV.

Vessel Wall MRI for Targeting Biopsies of Intracranial Vasculitis

Central nervous system vasculitides are elusive diseases that are challenging to diagnose because brain biopsies have high false-negative rates. We sought to test the ability of contrast-enhanced, high-resolution 3D vessel wall MR imaging to identify vascular inflammation and direct open biopsies of intracranial target vessels and adjacent brain parenchyma. Eight of 9 specimens revealed vascular inflammation. We conclude that vessel wall MR imaging can identify inflamed intracranial vessels, enabling precise localization of biopsy targets.

Primary angiitis of the central nervous system: diagnosis and treatment

Primary angiitis of the central nervous system (PACNS) represents a rare inflammatory disease affecting the brain and spinal cord. Stroke, encephalopathy, headache and seizures are major clinical manifestations. The diagnosis of PACNS is based on the combination of clinical presentation, imaging findings (magnetic resonance imaging and angiography), brain biopsy, and laboratory and cerebral spinal fluid (CSF) values. PACNS can either be confirmed by magnetic resonance angiography (MRA)/conventional angiography or tissue biopsy showing the presence of typical histopathological patterns. Identification of PACNS mimics is often challenging in clinical practice, but crucial to avoid far-reaching treatment decisions. In view of the severity of the disease, with considerable morbidity and mortality, early recognition and treatment initiation is necessary. Due to the rareness and heterogeneity of the disease, there is a lack of randomized data on treatment strategies. Retrospective studies suggest the combined administration of cyclophosphamide and glucocorticoids as induction therapy. Immunosuppressants such as azathioprine, methotrexate or mycophenolate mofetil are often applied for maintenance therapy. In addition, the beneficial effects of two biological agents (anti-CD20 monoclonal antibody rituximab and tumour necrosis factor-α blocker) have been reported. Nevertheless, diagnosis and treatment is still a clinical challenge, and further insights into the immunopathogenesis of PACNS are required to improve the diagnosis and management of patients. The present review provides a comprehensive overview of diagnostics, differential diagnoses, and therapeutic approaches of adult PACNS.

New onset refractory status epilepticus due to primary angiitis of the central nervous system

Primary Angiitis of the central nervous system is a rare and poorly understood variant of vasculitis. We narrate a case of a 46-year-old male who presented with new onset refractory status epilepticus mimicking autoimmune encephalitis. In this case we are reporting clues that could be useful for diagnosis and extensive literature review on the topic.

Subtypes of primary angiitis of the CNS identified by MRI patterns reflect the size of affected vessels

OBJECTIVE

To describe patterns of diagnostic findings, and identify subgroups of primary angiitis of the central nervous system (PACNS).

METHODS

We retrospectively analysed 31 patients with PACNS. Cases were selected by predetermined diagnostic criteria and stratified into biopsy-proven and imaging-based PACNS. We compared clinical characteristics, cerebrospinal fluid (CSF) findings and imaging results including high-resolution vessel wall MRI between groups.

RESULTS

There were 31 cases of PACNS (mean age 45.6 years, 58.1% female), of whom 17 (55%) were biopsy-proven, 14 (45%) were based on imaging findings. Patients with a positive biopsy had fewer infarcts (29.4% vs 85.7%, p=0.003), were more likely to have meningeal and parenchymal contrast enhancement (76.5% vs 28.6%, p=0.012), were less likely to have abnormal MR angiography (11.8% vs 100%, p<0.001) and did not show vessel wall enhancement at the time of diagnosis (0% vs 76.9%, p<0.001). In contrast, patients with imaging-based diagnosis showed more frequently multiple infarcts and vessel abnormalities, with vessel wall enhancement in most of the cases. Clinical characteristics and CSF analysis did not reveal marked differences between groups.

INTERPRETATION

Multi-parametric MRI distinguishes two subtypes of PACNS that most likely differ concerning the affected vessel size. Biopsy-proven PACNS primarily involves smaller vessels beyond the resolution of vascular imaging, while imaging-based PACNS affects predominantly medium-sized vessels leading to false-negative biopsy results. Using distinct MRI patterns may be helpful for selecting patients for appropriate invasive diagnostic modalities.

Concordance of Time-of-Flight MRA and Digital Subtraction Angiography in Adult Primary Central Nervous System Vasculitis

BACKGROUND AND PURPOSE

3D-TOF-MRA and DSA are 2 available tools to demonstrate neurovascular involvement in primary central nervous system vasculitis. We aimed to compare the diagnostic concordance of vessel imaging using 3D-TOF-MRA and DSA in patients with primary central nervous system vasculitis.

MATERIALS AND METHODS

We retrospectively identified all patients included in the French primary central nervous system vasculitis cohort of 85 patients who underwent, at baseline, both intracranial 3D-TOF-MRA and DSA in an interval of no more than 2 weeks and before treatment initiation. Two neuroradiologists independently reviewed all 3D-TOF-MRA and DSA imaging. Brain vasculature was divided into 25 arterial segments. Concordance between 3D-TOF-MRA and DSA for the identification of arterial stenosis was assessed by the Cohen κ Index.

RESULTS

Thirty-one patients met the inclusion criteria, including 20 imaged with a 1.5T MR unit and 11 with a 3T MR unit. Among the 25 patients (81%) with abnormal DSA findings, 24 demonstrated abnormal 3D-TOF-MRA findings, whereas all 6 remaining patients with normal DSA findings had normal 3D-TOF-MRA findings. In the per-segment analysis, concordance between 1.5T 3D-TOF-MRA and DSA was 0.82 (95% CI, 0.75-0.93), and between 3T 3D-TOF-MRA and DSA, it was 0.87 (95% CI, 0.78-0.91).

CONCLUSIONS

3D-TOF-MRA shows a high concordance with DSA in diagnostic performance when analyzing brain vasculature in patients with primary central nervous system vasculitis. In patients with negative 3T 3D-TOF-MRA findings, the added diagnostic value of DSA is limited.

Role of magnetic resonance imaging in the diagnosis of primary central nervous system angiitis

The present study reported on the use of magnetic resonance imaging (MRI) in the diagnosis of primary angiitis of the central nervous system (PACNS). A total of 19 consecutive patients with a clinical diagnosis of PACNS confirmed by clinical follow-up were enrolled in the present study. All patients underwent unenhanced and enhanced MRI prior to and after steroids or steroids plus immunosuppressive therapy. At baseline, all patients showed lesions on MRI in the grey and white matter. Lesions presented as slightly hypointense on T1-weighted images (T1WI), slightly hyperintense on T2WI, hyperintense on fluid-attenuated inversion recovery, iso- or slightly hyperintense on diffusion-weighted images (DWI) and hyperintense on apparent diffusion coefficient (ADC) mapping. After contrast injection, the lesions showed patchy, cord-like or goral enhancement. Seven cases had unilateral lesions and the other 12 cases had bilateral lesions. On all sequences, indistinct margins characterised most of the lesions, and certain lesions were oedematous. Treatment with steroids or steroids plus immunosuppressive agents resulted in improvement or disappearance of symptoms, and seventeen patients had evidently improved according to MRI. In conclusion, PACNS has unique characteristics on MRI; DWI, ADC mapping and enhanced images are of great importance for the diagnosis and clinical management of early-stage PACNS.

Diagnostic test results in primary CNS vasculitis: A systematic review of published cases

Background

Primary CNS vasculitis (PCNSV) can be diagnosed using cerebral angiography or histopathology combined with clinical features. The original diagnostic criteria, which weigh each test equally, have not been validated. Limited sensitivity and specificity for biopsy and angiography are recognized. We systematically reviewed results of diagnostic tests performed in patients with an ultimate diagnosis of PCNSV.

Methods

We searched the OVID Medline database and bibliographies for original cases of PCNSV. We recorded demographics, diagnostic tests used, and assessed agreement between angiography and biopsy when both tests were performed. We also recorded MRI and CSF results.

Results

We found 701 original cases with PCNSV diagnosed with angiography or pathology. A total of 269 patients (38.4%) had both cerebral angiography and histopathologic testing (biopsy/postmortem). Classic angiographic features of vasculitis were associated with pathologic confirmation in just 32 patients (4.6%). Seventy-four patients (10.6%) with any abnormality on angiography had a normal biopsy, and 99 patients (14.1%) with abnormal biopsies had normal angiography. Brain MRI was abnormal in 505/541 patients (93.3%) and CSF was abnormal in 360/484 patients (74.4%). Increasing use of angiography and decreasing histopathologic testing were found over time.

Conclusions

Cerebral angiography and pathologic tissue examination were undertaken in a minority of published cases with a diagnosis of PCNSV. When both diagnostic tests were performed, disagreement between them was more than 5 times more likely than agreement. Diagnostic criteria for PCNSV may require revision to classify the clinical, pathologic, and radiologic features of this condition more accurately.

Other cerebrovascular occlusive disease

In this chapter we review the optimal imaging modalities for subacute and chronic stroke. We discuss the utility of computed tomography (CT) and multimodal CT imaging. Further, we analyze the importance of specific magnetic resonance imaging sequences, such as diffusion-weighted imaging for acute ischemic stroke, T2/fluid-attenuated inversion recovery for subacute and chronic stroke, and susceptibility imaging for detection of intracranial hemorrhages. Different ischemic stroke mechanisms are reviewed, and how these imaging modalities may aid in the determination of such. Further, we analyze how topographic patterns in ischemic stroke may provide important clues to the diagnosis, in addition to the temporal evolution of the stroke. Lastly, specific cerebrovascular occlusive diseases are reviewed, with emphasis on the optimal imaging modalities and their findings in each condition.

Central nervous system vasculitis in adults: An update

Primary central nervous system vasculitis (PCNSV) is a challenging diagnosis due to broad clinical manifestations and variable specificity and sensitivity of laboratory and imaging diagnostic tools. Differential diagnosis includes reversible cerebral vasoconstriction syndrome (RCVS), secondary vasculitis of the CNS and other noninflammatory vasculopathies. Brain biopsy is essential for definitive diagnosis and to exclude mimickers. Recent data show that data large-vessel PCNSV present worse prognosis when compared to small-vessel PCNSV. Herein we review diagnosis and management of PCNSV, secondary vasculitis of CNS and RCVS.

[Primary central nervous system vasculitis]

Primary angiitis of the central nervous system (PACNS) is a rare disorder. However, it is often considered in the differential diagnosis of vascular or inflammatory CNS diseases. Diagnosis is challenging, as specific biomarkers are lacking and the clinical presentation can be variable. A definitive diagnosis can only be established by biopsy of the inflammatory changes in the vascular wall. Alternatively, the diagnosis of PACNS can also be based on the synopsis of clinical, radiological, and laboratory findings. Different subtypes of PACNS have been described in recent years, depending on the size of the affected vessels or histopathological patterns. Based on selective literature research in the database PubMed on the subject of CNS vasculitis, this article reviews the diagnostic characteristics and differential diagnosis of the condition. We suggest a diagnostic algorithm customized to the size of the affected vessels. Lastly, therapeutic options and the outcome of PACNS are briefly outlined.

The Role of Catheter Angiography in the Diagnosis of Central Nervous System Vasculitis

BACKGROUND

Central nervous system vasculitis (CNSV) is a rare disorder, the pathophysiology of which is not fully understood. It involves a combination of inflammation and thrombosis. CNSV is most commonly associated with headache, gradual changes in mental status, and focal neurological symptoms. Diagnosis requires the effective use of history, laboratory testing, imaging, and biopsy. Catheter angiography can be a powerful tool in the diagnosis when common and low-frequency angiographic manifestations of CNSV are considered. We review these manifestations and their place in the diagnostic algorithm of CNSV.

SUMMARY

We reviewed the PubMed database for case series of CNSV that included 5 or more patients. Demographic and angiographic findings were collected. Angiographic findings were dichotomized between common and low-frequency findings. A system for incorporating these findings into clinical decision-making is proposed.

KEY MESSAGE

CNSV is a diagnostic challenge due to the absence of a true gold standard test. In the absence of such a test, catheter angiography remains a central piece of the diagnostic puzzle when appropriately employed and interpreted.

Vascular disease

The child presenting with possible sentinel transient ischemic event or stroke requires prompt diagnosis so that strategies to limit injury and prevent recurrent stroke can be instituted. Cerebral arteriopathy is a potent risk factor for arterial ischemic stroke in childhood. Though acute imaging study in the setting of possible stroke is often a head computed tomography, when possible magnetic resonance imaging (MRI) is recommended as the first-line study as confirmation and imaging evaluation of ischemic stroke will typically require MRI. The MRI scanning approach should include diffusion-weighted imaging (DWI) early in the sequence order, since normal DWI excludes acute infarct with rare exception. In most cases, arterial imaging with time-of-flight (TOF) magnetic resonance angiography (MRA) is warranted. Dedicated MRA may not be possible in the acute setting, but should be pursued as promptly as possible, particularly in the child with findings and history suggestive of arteriopathy, given the high risk of recurrent stroke in these children. MRA can overestimate the degree of arterial compromise due to complex/turbulent flow, and be insensitive to subtle vessel irregularity due to resolution and complex flow. In cases with high imaging suspicion for dissection despite normal MRA findings, catheter angiogram is indicated. A thoughtful, stepwise approach to arterial neuroimaging is critical to optimize diagnosis, treatment, and primary and secondary prevention of childhood stroke.

Imaging of Cerebral Vasculitis

Background

In young patients, vasculitic stenoses of cerebral blood vessels are an important cause of cerebral ischaemia. Diagnosis may prove very difficult.

Summary of review

The diagnostic process is usually initiated by the detection of brain lesions consistent with cerebral vasculitis. Multiple infarcts of various ages in more than one vascular territory are thought to be suggestive of a vascular inflammatory disease. The next step in the imaging of patients with suspected vasculitis is the search for an underlying vascular stenosis. Today, magnetic resonance angiography is the principal modality for the investigation of patients thought to have intracranial stenoses. At 1·5 T, only large brain arteries can be imaged with a high diagnostic accuracy. Intraarterial DSA remains an indispensable tool for the investigation of medium and small brain artery stenoses.

Conclusions

However, contrast-enhanced magnetic resonance imaging may be able to demonstrate wall thickening and contrast uptake in large cerebral arteries, obviating biopsy in patients with basal vasculitis.

A rare case of tumor-mimicking primary angiitis of the central nervous system

Primary angiitis of the central nervous system (PACNS) is a rare, but severe vascular disease. The present study reports the case of a 42-year-old male who developed PACNS. Magnetic resonance imaging (MRI) scans initially led to a misleading diagnosis of malignant glioma, and surgery was performed. The mass was resected, and a pathological examination confirmed a cerebral vasculitis. Single therapy with high doses of steroid did not improve the patient's condition, while a subsequent lesion appeared on the opposite side one year later. Combined therapy with methylprednisone and cyclophosphamide resulted in a great improvement for the patient. No relapse occurred during one year's follow-up. Although a tumor-mimicking PACNS has no established imaging features, a diagnosis of tumor-mimicking PACNS should be suspected when the MRI reveals inappropriate presentations of a tumor. Greater awareness of this potential manifestation of PACNS may facilitate more prompt diagnosis and treatment.

Diagnostic Value and Safety of Brain Biopsy in Patients With Cryptogenic Neurological Disease: A Systematic Review and Meta-analysis of 831 Cases

BACKGROUND

The role of brain biopsy in patients with cryptogenic neurological disease is uncertain.

OBJECTIVE

To determine the risks and benefits of diagnostic brain biopsy for nonneoplastic indications in immunocompetent patients.

METHODS

Appropriate studies were identified by searching electronic databases.

RESULTS

We screened 3645 abstracts and included 20 studies with a total of 831 patients. Indications for biopsy were: (1a) severe neurological disease of unknown etiology in adults (n = 7) and (1b) in children (n = 2); (2) suspected primary angiitis of the central nervous system (PACNS) (n = 3); (3) chronic meningitis of unknown cause (n = 3); (4) atypical dementia (n = 4); and (5) nonneoplastic disease (n = 1). Diagnostic success rates calculated for subgroups were 51.3% (34.5-68.1) for 1a, 53.8% (42.9-64.5) for 1b, 74.7% (64.0-84.1) for 2, 30.3% (17.2-45.4) for 3, and 60.8% (41.2-78.8) for 4. Clinical impact rates were 30.5% (13.6-50.6) for 1a (n = 6), 67.1% (42.8-87.3) for 1b (n = 2), 8.3% (2.3-20.0) for 3 (n = 1), and 14.2% (6.5-24.3) for 4 (n = 2). Lymphoma (n = 32) and Creutzfeldt-Jakob disease (n = 30) were the most common diagnoses on the final histopathology reports of positive brain biopsies in 1a. In 1b, encephalitis (n = 7), PACNS (n = 6), and demyelination (n = 6) were the most common. The odds ratio for achieving a diagnostic biopsy when there was a radiological target was 3.70 (P = .014, 95% confidence interval, 1.31-10.42).

CONCLUSION

Brain biopsy in cryptogenic neurological disease was associated with the highest diagnostic yield in patients with suspected PACNS. The greatest clinical impact was seen in children with cryptogenic neurological disease. The presence of a radiological target was associated with a higher diagnostic yield.

Vessel wall imaging for intracranial vascular disease evaluation

Accurate and timely diagnosis of intracranial vasculopathies is important owing to the significant risk of morbidity with delayed and/or incorrect diagnosis both from the disease process and inappropriate therapies. Conventional luminal imaging techniques for analysis of intracranial vasculopathies are limited to evaluation of changes in the vessel lumen. Vessel wall MRI techniques can allow direct characterization of pathologic changes of the vessel wall. These techniques may improve diagnostic accuracy and improve patient outcomes. Extracranial carotid vessel wall imaging has been extensively investigated in patients with atherosclerotic disease and has been shown to accurately assess plaque composition and identify vulnerable plaque characteristics that may predict stroke risk beyond luminal stenosis alone. This review provides a brief history of vessel wall MRI, an overview of the intracranial vessel wall MRI techniques, its applications, and imaging findings of various intracranial vasculopathies pertinent to the neurointerventionalist, neurologist, and neuroradiologist. We searched MEDLINE, PubMed, and Google for English publications containing any of the following terms: 'intracranial vessel wall imaging', 'intracranial vessel wall', and 'intracranial vessel wall MRI'.

Primary angiitis of the central nervous system in adults and children

Primary angiitis of the central nervous system (PACNS) is a rare disease, although it is increasingly recognized both in adults and children. Little is known about pathogenesis, but efforts at classification into subtypes are being made, and the distinction of PACNS from reversible cerebral vasoconstriction syndrome has been a major advance. The prognosis for improvement, or at least stabilization, of neurologic function is good with prompt and aggressive treatment, but the diagnosis continues to be challenging. Refinement of treatment strategies is needed. Multicenter collaboration may be crucial to make additional progress via randomized trials.

An update of the Mayo Clinic cohort of patients with adult primary central nervous system vasculitis: description of 163 patients

Primary central nervous system vasculitis (PCNSV) is an uncommon condition in which lesions are limited to vessels of the brain and spinal cord. Because the clinical manifestations are not specific, the diagnosis is often difficult, and permanent disability and death are frequent outcomes. This study is based on a cohort of 163 consecutive patients with PCNSV who were examined at the Mayo Clinic over a 29-year period from 1983 to 2011. The aim of the study was to define the characteristics of these patients, which represents the largest series in adults reported to date. A total of 105 patients were diagnosed by angiographic findings and 58 by biopsy results. The patients diagnosed by biopsy more frequently had at presentation cognitive dysfunction, greater cerebrospinal fluid total protein concentrations, less frequent cerebral infarcts, and more frequent leptomeningeal gadolinium-enhanced lesions on magnetic resonance imaging (MRI), along with less mortality and disability at last follow-up. The patients diagnosed by angiograms more frequently had at presentation hemiparesis or a persistent neurologic deficit or stroke, more frequent infarcts on MRI and an increased mortality. These differences were mainly related to the different size of the vessels involved in the 2 groups. Although most patients responded to therapy with glucocorticoids alone or in conjunction with cyclophosphamide and tended to improve during the follow-up period, an overall increased mortality rate was observed. Relapses occurred in one-quarter of the patients and were less frequent in patients treated with prednisone and cyclophosphamide compared with those treated with prednisone alone. The mortality rate and degree of disability at last follow-up were greater in those with increasing age, cerebral infarctions on MRI, angiographic large vessel involvement, and diagnosis made by angiography alone, but were lower in those with gadolinium-enhanced lesions on MRI and in those with cerebral amyloid angiopathy. The annual incidence rate of PCNSV was estimated at 2.4 cases per 1,000,000 person-years. PCNSV appears to consist of several subsets defined by the size of the vessels involved, the clinical characteristics at presentation, MRI findings, and histopathological patterns on biopsy. Early recognition and treatment may reduce poor outcomes.

Postpartum reversible cerebral vasoconstriction syndrome: Review and analysis of the current data

Postpartum reversible cerebral vasoconstriction syndrome (PPRCVS) is a rare but serious cause of headache that occurs in the early postpartum period. The rarity of this disorder has limited the current literature to single case reports and small, observational case series. The lack of familiarity with PPRCVS may contribute to mismanagement of these unique patients and lead to poor outcomes. To address current gaps in the understanding of PPRCVS, this review and data analysis characterizes the demographics, presentation, clinical course, management and prognosis of PPRCVS and provides a general review of the epidemiology, pathophysiology and diagnosis to assist clinicians who may care for patients with this rare disorder.

Cerebral convexity subarachnoid hemorrhage: various causes and role of diagnostic imaging

Computed tomography (CT) and magnetic resonance imaging (MRI) have made it relatively easy to diagnose cortical convexity subarachnoid hemorrhages (cSAH); however, the evaluation of these hemorrhages should not be limited to size and location. It is imperative that possible underlying etiologies be identified so that clinicians may properly treat and prevent this potentially catastrophic event. The goal of this article is to review etiologies of cortical convexity subarachnoid hemorrhages, from common causes such as cerebral amyloid angiopathy to less common causes such as reversible cerebral vasoconstriction syndrome and moyamoya. The specific imaging findings of each etiology that may be responsible for these hemorrhages are described in this article so that the radiologist may properly aid in the diagnosis of the underlying cause.

Biopsy of the superficial cortex: predictors of effectiveness and outcomes

BACKGROUND

Brain biopsies of superficial cortex are performed for diagnosis of neurological diseases, but preoperative predictors of successful diagnosis and risks are lacking.

OBJECTIVE

We evaluated effectiveness and outcomes of superficial cortical biopsies and determined preoperative predictors of diagnosis, outcomes, morbidities, and mortality.

METHODS

A single-institution retrospective analysis of 170 patients who underwent open brain biopsies of superficial cortex was performed. Clinical predictors of effectiveness and outcomes were determined using univariate/multivariate analyses and a system for risk-benefit stratification was created and tested.

RESULTS

Brain biopsies led to successful diagnosis in 122 of 170 (71.8%) and affected management in 97 of 170 (57.1%) cases. Factors increasing the odds of diagnostic pathology included age older than 45 years (odds ratio [OR]: 2.67, 95% confidence interval [CI]: 1.34-5.27, P < .01), previous cancer diagnosis (OR: 3.64, 95% CI: 1.69-7.85, P < .001), focal (OR: 3.90, 95% CI: 1.91-8.00, P < .001) and enhancing (OR: 5.03, 95% CI: 2.41-10.52, P < .001) lesions on magnetic resonance imaging, biopsy of specific lesions on magnetic resonance imaging (OR: 9.34, 95% CI: 4.29-20.33, P < .001), and use of intraoperative navigation (OR: 6.59, 95% CI: 3.04-14.28, P < .001). Brain biopsies led to symptomatic intracranial hemorrhage, seizures, other significant morbidities, and perioperative mortality in 12.4%, 16.2%, 37.1%, and 8% of cases, respectively. Risk of postoperative intracranial hemorrhage was increased by a history of aspirin use (OR: 2.51, 95% CI: 1.23-5.28, P < .05) and age older than 60 years (OR: 2.66, 95% CI: 1.36-5.18, P < .01).

CONCLUSION

Effectiveness and risk of morbidity/mortality can be estimated preoperatively for patients undergoing open brain biopsies of the superficial cortex. Older age and specific imaging characteristics increase the odds of diagnostic biopsy. Conversely, older age and aspirin use increases the risk of postoperative complications.

Multiple sclerosis: diagnosis, differential diagnosis, and clinical presentation

The diagnosis of multiple sclerosis (MS) is based on demonstrating evidence of inflammatory-demyelinating injury within the central nervous system that is disseminated in both time and space. Diagnosis is made through a combination of the clinical history, neurologic examination, magnetic resonance imaging and the exclusion of other diagnostic possibilities. Other so-called "paraclinical" tests, including the examination of the cerebrospinal fluid, the recording of evoked potentials, urodynamic studies of bladder function, and ocular coherence tomography, may be helpful in establishing the diagnosis for individual patients, but are often unnecessary. Differential diagnosis in MS must be guided by clinical presentation and neurologic localization. While the list of conditions that can mimic MS clinically or radiologically is long, in clinical practice there are few conditions that truly mimic MS on both fronts. A positive test for a putative MS "mimic" does not unto itself exclude the diagnosis of MS. Typical symptoms of MS include discrete episodes ("attacks" or "relapses") of numbness, tingling, weakness, vision loss, gait impairment, incoordination, imbalance, and bladder dysfunction. In between attacks, patients tend to be stable, but may experience fatigue and heat sensitivity. Some MS patients go on to experience, or only experience, an insidious worsening of neurologic function and accumulation of disability ("progression") that is not associated with discrete relapse activity. Progression accounts for most of the long-term disability in MS. Diagnostic criteria for MS have evolved over the past several decades, with each revision impacting the apparent prevalence and prognosis of the disorder - the result has been to encourage earlier diagnosis without compromising accuracy.

The activation pattern of macrophages in giant cell (temporal) arteritis and primary angiitis of the central nervous system

To determine if the pattern of macrophage activation reflects differences in the pathogenesis and clinical presentation of giant cell arteritis and primary angiitis of the central nervous system, specimens of 10 patients with giant cell arteritis and five with primary angiitis of the central nervous system were immunohistochemically studied and the expression of the macrophage activation markers 27E10, MRP14, MRP8 and 25F9 was determined in the vasculitic infiltrates. Thus, a partly different expression pattern of macrophage activation markers in giant cell arteritis and primary angiitis of the central nervous system was observed. The group comparison revealed that giant cell arteritis cases had significantly higher numbers of acute activated MRP14-positive macrophages, whereas primary angiitis of the central nervous system is characterized by a tendency toward more MRP8-positive intermediate/late activated macrophages. Furthermore, in giant cell arteritis comparably fewer CD8-positive lymphocytes were observed. These observations suggest, that despite their histopathological similarities, giant cell arteritis and primary angiitis of the central nervous system appear to represent either distinct entities within the spectrum of granulomatous vasculitides or different stages of similar disease processes. Their discrete clinical presentation is reflected by different activation patterns of macrophages, which may characterize giant cell arteritis as a more acute process and primary angiitis of the central nervous system as a more advanced inflammatory process.