Tumefactive Primary Central Nervous System Vasculitis: Imaging Findings of a Rare and Underrecognized Neuroinflammatory Disease

Pearls & Oy-sters: Tumour-Like Mass Lesion Secondary to Primary CNS Vasculitis

Primary CNS vasculitis (PCNSV) is uncommonly considered in the differential diagnosis of tumor-like lesions. This case report of tumefactive PCNSV highlights imaging features that should increase clinical suspicion for CNS vasculitis, potentially lending to earlier diagnosis and treatment. A 62-year-old man presented with a 1-month history of focal motor seizures and cortical sensory loss localizing to the right frontoparietal lobe. Noncontrast head CT was suggestive of glioma, resulting in intravenous dexamethasone administration and admission to neurosurgery. MRI appearance was atypical for glioma, with relative preservation of regional anatomy, intralesional microhemorrhage, and patchy peripheral enhancement. Despite normal CT angiogram, CSF, and serum inflammatory markers, brain biopsy was suggestive of lymphocytic vasculitis. Extensive workup for secondary causes was negative, and he was diagnosed with tumefactive PCNSV. Treatment with corticosteroids and cyclophosphamide resulted in sustained clinical and radiologic improvement. Tumefactive PCNSV is an angiogram-negative small-vessel vasculitis that has a lymphocytic histologic pattern. Tumefactive PCNSV constitutes over 10% of PCNSV cases and can be recognized by the presence of intralesional microhemorrhages, absence of diffusion restriction, and a patchy or nodular enhancement pattern. The most important mimicker is CNS lymphoma, which has a similar imaging and histologic pattern. If individuals with tumefactive PCNSV do not have a sustained immunotherapy response, repeat biopsy should be promptly performed.

Vasculitis in the Central Nervous System: Etiology, Characteristics, and Outcomes in a Large Single-Center Cohort

Background and Purpose

For the management of central nervous system (CNS) vasculitis, it is crucial to differentiate between primary and secondary CNS vasculitis and to understand the respective etiologies. We assessed the etiology, characteristics, and outcomes of patients with CNS vasculitis.

Methods

A single-center retrospective chart review was conducted at the University of Utah, Department of Neurology, between February 2011 and October 2022.

Results

The median age of the 44 included patients at diagnosis was 54 years; 25.0% were men. Compared to primary CNS vasculitis, secondary CNS vasculitis exhibits higher fever incidence (observed in infectious and connective tissue disorder [CTD]-associated vasculitis), low glucose levels (mostly in infectious vasculitis) and unique cerebrospinal fluid oligoclonal bands (observed in infectious and CTD-associated vasculitis). Patients with inflammatory cerebral amyloid angiopathy (CAA) were older and more commonly had microhemorrhage than primary angiitis of the CNS (PACNS). All patients with CTD-associated vasculitis had a known history of CTD at presentation. Brain biopsies were performed on 10 of 17 PACNS patients and 4 of 8 inflammatory CAA patients, confirming vasculitis in 7 and 4 patients, respectively. Intravenous methylprednisolone was the predominant induction therapy (63.6%), and cyclophosphamide was the most used adjunctive therapy. Cyclophosphamide, rituximab, azathioprine, and mycophenolate mofetil were utilized as maintenance therapy, often with concurrent prednisone. Patients with inflammatory CAA had a higher tendency for relapse rates than PACNS.

Conclusions

This study highlights the variations in patients' characteristics, symptoms, and treatment for CNS vasculitis. Understanding these differences can lead to more efficient diagnostic and management strategies.

Usefulness of Different Imaging Methods in the Diagnosis of Cerebral Vasculopathy

Assessment of cerebral vasculopathies is challenging and requires understanding the utility of different imaging methods. Various techniques are available to image the vessel lumen, each with unique advantages and disadvantages. Bolus-based CT and MR angiography requires careful timing of a contrast bolus to provide optimal luminal enhancement. Non-contrast MRA techniques do not require a contrast agent and can provide images with little venous contamination. Digital subtraction angiography remains the gold standard but is invasive, while VW-MRI provides a non-invasive way of assessing vessel wall pathology. Conventional brain MRI has high sensitivity in the diagnosis of vasculitis but findings are nonspecific.

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.

Tumefactive brain parenchymal neurosarcoidosis

BACKGROUND

Enhancing brain parenchymal disease, and especially tumefactive lesions, are an uncommon manifestation of neurosarcoidosis. Little is known about the clinical features of tumefactive lesions and their impact on management and outcomes, which this study aims to characterize.

METHODS

Patients with pathologically-confirmed sarcoidosis were retrospectively reviewed and included if brain lesions were: (1) intraparenchymal, (2) larger than 1 cm in diameter, and (3) associated with edema and/or mass effect.

RESULTS

Nine patients (9/214, 4.2%) were included. Median onset age was 37 years. Diagnosis was confirmed by brain parenchymal biopsies in 5 (55.6%). Median modified Rankin scale (mRS) score was 2 (range 1-4) at initial presentation. Common manifestations included headache (77.8%), cognitive dysfunction (66.7%), and seizures (44.4%). Sixteen lesions were present in 9 patients. The frontal lobe (31.3%) was most affected, followed by the subinsular region (12.5%), basal ganglia (12.5%%), cerebellum (12.5%), and pons (12.5%). MRI characteristics of the dominant lesions included spherical morphology (77.8%), perilesional edema (100.0%), mass effect (55.6%), well-demarcated borders (66.7%), and contrast enhancement (100.0%; 55.6% heterogeneous). Leptomeningitis was frequently present (77.8%). All required corticosteroid-sparing treatments, and most (55.6%) needed at least a third line of treatment (infliximab used in 44.4%). All patients relapsed (median 3 relapses, range 1-9). Median last mRS was 1.0 after median follow-up of 86 months, with significant residual deficits in 55.6%.

CONCLUSION

Tumefactive brain parenchymal lesions are uncommon, usually affect the supratentorial brain along with leptomeningitis, and are refractory to initial treatments with a high risk of relapse. Significant sequelae were encountered despite a favorable median last mRS.

Central and Peripheral Nervous System Complications of Vasculitis Syndromes From Pathology to Bedside: Part 1-Central Nervous System

PURPOSE OF REVIEW

The aim of this review is to provide a comprehensive update on the clinical assessment, diagnosis, complications, and treatment of primary central nervous system vasculitis (PCNSV).

RECENT FINDINGS

The developments in neuroimaging, molecular testing, and cerebral biopsy have enhanced clinical assessment and decision making, providing novel insights to prevent misdiagnosis increasing diagnostic certainty. Advances in imaging techniques visualizing the wall of intracranial vessels have improved the possibility to distinguish inflammatory from non-inflammatory vascular lesions. Large recent studies have revealed a more varied histopathological pictures and disclosed an association with amyloid angiopathy. Unfortunately, therapy remains largely empiric. PCNSV is a heterogeneous group of disorders encompassing different clinical subsets that may differ in terms of prognosis and therapy. Recent evidence has described a more benign course, with good response to therapy. New diagnostic techniques will play soon a pivotal role in the appropriate diagnosis and prompt management of PCNSV.

Novel method using DW-MRI and ADC images to guide stereotactic biopsy for the diagnosis small primary angiitis of the central nervous system: a case report

Objective

To determine the role of diffusion-weighted magnetic resonance imaging (DW-MRI) and apparent diffusion coefficient (ADC) imaging to guide stereotactic biopsy for the diagnosis of intracranial angiitis.

Case presentation

In a 28-year-old woman who had experienced inactive headache and right limbs numbness for 4 days, preoperative magnetic resonance (MR) scanning, enhanced scanning, diffusion tensor imaging, magnetic resonance spectroscopy, diffusion-weighted imaging (DWI), and ADC image scanning were performed. Stereotactic biopsy was performed in one target where the area of edema detected with MR FLAIR, and two targets where the area shown as a high-value and a lower value area in the DWI/ADC image. Pathological examinations together with computed tomographic and enhanced MRI scans were conducted after surgery. A preoperative enhanced MRI scan showed a uniform low-intensity lesion in the patient’s left centrum semiovale, with a volume of 3.1 cm³. The DWI and ADC images showed uneven high-intensity signals and different ADC values in the lesion area, respectively. During surgery, tissues around the lesion and the lesion center were sampled at the three selected targets. The postoperative pathological diagnosis was primary angiitis of the central nervous system, and the patient was given anti-inflammatory medication and hormone therapy. The 3-year follow-up confirmed that the patient had recovered well, with a Glasgow Outcome Scale score of five.

Conclusion

DW-MRI and ADC images can be reliably used to determine the location of small intracranial lesions, and guide stereotactic biopsy to facilitate the diagnosis of primary vasculitis of the central nervous system.