Pseudotumoral presentation of primary central nervous system vasculitis

Primary Angiitis of the Central Nervous System in Adults: A Comprehensive Review of 76 Biopsy-Proven Case Reports

Purpose

Primary angiitis of the adult central nervous system (PACNS) is an increasingly recognized but limited disease. Using previous case reports, we sought to summarize the clinical symptoms, imaging manifestations, treatment, and prognosis of patients with biopsy-confirmed PACNS to guide clinical diagnosis and management.

Methods

We searched the Web of Science database for studies published from January 2000 to April 2023, with the language set to English and the document type limited to [Article or Review or Letter or Editorial Material]. A systematic review of all case reports met the inclusion and exclusion criteria was performed. These patients' clinical, pathological, and imaging characteristics were analyzed, and treatment and prognostic data were summarized.

Results

We analyzed 69 articles, including 76 patients with biopsy-confirmed PACNS. And 57.9% of the patients were male, the median age at presentation was 47.0 years, and focal neurological deficits were the most common symptom in patients (78.9%), followed by headache (52.6%). The median duration of biopsy was 1.1 months, of which 49 (64.5%) patients were lymphocytic, 13 (17.1%) were granulomatous, 11 (14.5%) were amyloidotic, and 3 (3.9%) were necrotizing PACNS. Relapse events occurred in 41 (53.9%) patients, including 34 (44.2%) relapses and 8 (10.5%) deaths. Univariate logistic regression analysis revealed that symptomatic epilepsy, prolonged biopsy time window, and CD20 expression in pathological tissues might be independent risk factors for recurrent events in patients (HR=4.69, 95% CI: 1.51-14.54, p=0.007; HR=1.11, 95% CI: 1.00-1.22, p=0.043; HR=5.33, 95% CI: 1.07-26.61, p=0.041).

Conclusion

Adult PACNS is associated with frequent relapses and high mortality. Symptomatic epilepsy, prolonged biopsy time window, and CD20 expression in pathological tissue may be associated with recurrent events.

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

Primary central nervous system vasculitis (PCNSV) is a poorly understood neuroinflammatory disease of the CNS affecting the intracranial vasculature. Although PCNSV classically manifests as a multifocal beaded narrowing of the intracranial vessels, some patients may not have angiographic abnormalities. A rare subset of patients with PCNSV present with masslike brain lesions mimicking a neoplasm. In this article, we retrospectively review 10 biopsy-confirmed cases of tumefactive PCNSV (t-PCNSV). All cases of t-PCNSV in our series that underwent CTA or MRA were found to have normal large and medium-sized vessels. T-PCNSV had a variable MR imaging appearance with most cases showing cortical/subcortical enhancing masslike lesion (70%), often with microhemorrhages (80%). Diffusion restriction was absent in all lesions. In summary, normal vascular imaging does not exclude the diagnosis of t-PCNSV. Advanced imaging techniques including MR perfusion and MR spectroscopy failed to demonstrate specific findings for t-PCNSV but assisted in excluding neoplasm in the differential diagnosis. Biopsy remains mandatory for definitive diagnosis.

Glial and neuronal antibodies in patients with idiopathic intracranial hypertension

Headache and visual disturbances are the main presenting symptoms of idiopathic intracranial hypertension (IIH) characterized by increased intracranial pressure (ICP) with an unknown cause. We aimed to investigate the antibodies against optic neuritis-associated glial antigens, aquaporin-4 (AQP4) and myelin oligodendrocyte glycoprotein (MOG) and uncharacterized neuronal membrane antigens in IIH patients. Consecutive patients diagnosed according to Friedman revised diagnostic criteria and control subjects were included after their consent. All serum samples were analyzed for antibodies against AQP4 and MOG using cell-based immunofluorescent assays and for uncharacterized neuronal membrane antigens by indirect immunocytochemistry utilizing live neurons. Sera of 34 patients with IIH and 40 control subjects were investigated but none of the patients showed AQP4 and MOG antibodies. However, serum IgG of five IIH patients showed reactivity against membrane antigens of rat hippocampal and cortical neurons. Interestingly, three out of these five patients had nonspecific white matter lesions on MRI, whereas only four of all other patients had these lesions (p = 0.048). AQP4 and MOG antibodies do not seem to have a role in the pathophysiology of IIH. However, association of immunocytochemistry findings with the presence of white matter lesions may suggest that immunological factors contribute to the pathogenesis of IIH in at least some of the patients.

Pseudotumoral brain lesions: MRI review

Single or multiple space-occupying lesions on brain MRI, with or without contrast enhancement and/or perilesional oedema, evoke a neoplastic origin. However, a multitude of non-neoplastic disorders can simulate cerebral neoplasia. In this review, we will discuss the MRI characteristics of non-neoplastic disorders that can mimic cerebral neoplasia. Distinguishing MRI characteristics are discussed for each of these non-neoplastic disorders.