High-Resolution Vessel Wall MRI: Appearance of Intravascular Lymphoma Mimics Central Nervous System Vasculitis

Intravascular large cell B lymphoma presenting as central nervous system pseudo-vasculitis: A rare diagnostic challenge

Intravascular large B cell lymphoma (IVLBCL) is a very rare subtype of aggressive non-Hodgkin B cell lymphoma characterized by intravascular proliferation of clonal B lymphocytes, classically associated with pulmonary and cutaneous disease and, less frequently, with central nervous system (CNS) involvement. Brain imaging findings are usually non-specific, with evidence of multiple vascular occlusions and stroke as non-specific multifocal abnormalities. We present an exceptionally rare case of IVLBCL in a patient with unexplained inflammatory syndrome with B symptoms and rapidly progressive neurological impairment, with multifocal hemorrhagic and tumefactive brain lesions seen on MRI. We suggest that in this clinical setting, the presence of tumefactive and hemorrhagic lesions should raise suspicion for IVLBCL and lead to the decision to perform a biopsy, which, nonetheless, remains the diagnostic gold standard.

Isolated middle cerebral artery stenosis caused by syphilitic vasculitis

BACKGROUND

Syphilitic vasculitis (SV) is rare and difficult to be diagnosed. High-resolution vessel wall magnetic resonance imaging (HR-VWI) might be valuable in the diagnosis by differentiating SV from other vessel wall pathologies.

METHODS

We report a rare case with severe isolated middle cerebral artery (MCA) stenosis and cerebral infarction, which was evaluated by serial HR-VWI.

RESULTS

A 46-year-old woman presented with an acute infarct in the left basal ganglia and severe isolated stenosis in left middle cerebral artery (MCA). Cerebrospinal fluid (CSF) analysis was performed and the findings were consistent with neurosyphilis diagnosis. The MCA stenosis was also suspected to be the result of SV. HR-VWI revealed the evidence of concentric thickening and circular uniform enhancement of the arterial wall. After two cycles of anti-syphilis treatment, subsequent HR-VWI showed that the MCA stenosis was reduced significantly except slight enhancement of the arterial wall, which confirmed that the SV caused the isolated MCA stenosis.

CONCLUSIONS

HR-VWI could be an important diagnostic tool for isolated middle cerebral artery stenosis caused by SV, which could serve as a biomarker for assessing the response to anti-syphilis treatment in the future.

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.

Ischemic Optic Neuropathy Secondary to Intravascular Lymphoma

BACKGROUND

To describe a case of optic neuropathy associated with intravascular lymphoma (IVL).

METHODS

Case report and review of the literature.

RESULTS

A case of asymmetric binocular vision loss is described, preceded by transient vision loss. Associated optic perineural enhancement and enhancing and diffusion-positive cortical lesions were observed on magnetic resonance imaging. Biopsy of the cerebellum revealed exclusively intraluminal neoplastic B-cells consistent with IVL.

CONCLUSIONS

Patients with IVL may rarely present with optic nerve involvement, presumably due to small vessel occlusion. The presentation may mimic features of anterior ischemic optic neuropathy including an acute onset and disc edema. Although optic nerve enhancement and associated white matter lesions may suggest optic neuritis, enhancement of the optic nerve sheath, as in this case, has a wide differential diagnosis, which includes giant cell arteritis. IVL should be considered in atypical cases of optic neuropathy accompanied by enhancing, diffusion-positive brain lesions that are not within a specific vascular territory.

[Vasculitis mimics]

Vasculitis mimics need to be differentiated from primary and secondary vasculitides as described in the Chapel Hill nomenclature. The clinical symptomatology resembles that of vasculitis of small and medium, rarely also large vessels and hence imitates the classical vasculitic disorders. Pathogenetically, the causes are partly genetic mutations, embolization syndromes, infections and substance abuse. Also, B‑cell lymphomas can mimic vasculitis. The present manuscript summarizes the vasculitis mimics.

[Misleading cerebral arterial wall gadolinium-enhancement in malignant lymphoma]

A previously healthy, 77-year-old woman presented with gradual cognitive decline and acute gait imbalance. On admission, despite no obvious paralysis, she tilted to the right. Her Mini-Mental State Examination score was slightly low (23/30). Gadolinium-enhanced, high-resolution T₁-weighted MRI showed abnormal arterial wall enhancement at the bilateral middle cerebral and right internal carotid arteries. The combination of arterial and parenchymal enhancement limited to the central nervous system (CNS), normal laboratory data including soluble interleukin-2 receptor, and random skin and bone-marrow biopsies was suggested of primary angiitis of the CNS (PACNS). However, a biopsy specimen from the right insula showed CD20-positive lymphoma cells indicative of diffuse large B-cell lymphoma. After receiving chemotherapy, above-mentioned abnormal findings were significantly improved. Considering the increasing clinical application of high resolution MRI, there is a risk that patients may receive a presumptive diagnosis of PACNS and immunosuppressive treatment without biopsy confirmation. It should be noted that a combination of abnormal arterial wall and linear parenchymal enhancement similar to that found for PACNS on high-resolution MRI may occur in patients with primary central nervous system lymphoma.

Cav-1 promotes atherosclerosis by activating JNK-associated signaling

The objective of the study is to calculate the role and underlying the molecular mechanisms of caveolin-1 (Cav-1) in atherosclerosis (AS). Cav-1 was mainly expressed in the endothelial cells of atherosclerotic lesions in both human patients and apolipoprotein E deficient (ApoE^-/-) mice. Cav-1 deficiency (Cav-1^-/-) attenuated high-fat diet (HFD)-induced atherosclerotic lesions in ApoE^-/- mice, supported by the reduced aortic plaques. Cav-1^-/- reduced the macrophage content and decreased the release of inflammation-related cytokines or chemokine in serum or abdominal aortas, accompanied with the inactivation of inhibitor κB kinase κ (IKKβ)/p65/IκBα signaling pathway. Also, the activity of mitogen-activated protein kinases 7/c-Jun-N-terminal kinase (MKK7/JNK) signaling was decreased by Cav-1^-/-. In addition, oxidative stress induced by HFD in ApoE^-/- mice was alleviated by Cav-1^-/-. In response to HFD, Cav-1^-/- markedly reduced triglyceride (TG), total cholesterol (TC), low-density lipoprotein-cholesterol (LDLC) and very low-density lipoprotein-cholesterol (VLDLC) in serum of HFD-fed ApoE^-/- mice, whereas enhanced high-density lipoprotein-cholesterol (HDLC) contents. Consistent with these findings, haematoxylin and eosin (H&E) and Oil Red O staining showed fewer lipid droplets in the liver of Cav-1-deficient mice. Further, real time-quantitative PCR (RT-qPCR) analysis indicated that Cav-1^-/- alleviated dyslipidemia both in liver and abdominal aortas of ApoE^-/- mice fed with HFD. Cav-1 inhibition-induced attenuation of inflammatory response, oxidative stress and dyslipidemia were confirmed in vitro using mouse vascular smooth muscle cells (VSMCs) treated with ox-LDL. Surprisingly, the processes regulated by Cav-1-knockdown could be abolished through promoting JNK activation in ox-LDL-treated VSMCs. In conclusion, Cav-1 expression could promote HFD-induced AS in a JNK-dependent manner.

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.