# Unilateral Hemispheric Hyperperfusion in Intravascular Large B-cell Lymphoma

## TL;DR

A rare case of intravascular large B-cell lymphoma presented with seizures and was detected via MRI showing unusual brain blood flow.

## Contribution

Highlights ASL MRI as a potential diagnostic tool for IVLBCL in patients with refractory seizures.

## Key findings

- Unilateral hemispheric hyperperfusion on ASL was the only abnormal MRI finding in a patient with IVLBCL.
- IVLBCL was diagnosed via elevated LDH and sIL-2R levels, confirmed by skin and bone marrow biopsy.
- The case emphasizes the importance of considering IVLBCL in patients with refractory seizures and atypical MRI findings.

## Abstract

The diagnosis of intravascular large B-cell lymphoma (IVLBCL) is often challenging owing to its nonspecific clinical manifestations and imaging findings. Herein, we present a rare case of IVLBCL in which seizure was the initial symptom, and unilateral hemispheric hyperperfusion on arterial spin labeling (ASL) was the only abnormal finding observed on brain magnetic resonance imaging (MRI). A 68-year-old male with a history of hypertension and type 2 diabetes was transferred to the emergency room owing to the sudden onset of altered consciousness and abnormal behavior. Upon arrival, the patient was disoriented and confused, and cerebrospinal fluid analysis revealed pleocytosis and elevated protein level. Even after the administration of acyclovir and antiepileptic drugs, his consciousness remained impaired, with repeated transient right hemiparesis indicating a focal seizure. The initial and follow-up MRI scans showed no obvious abnormalities in diffusion-weighted imaging (DWI), T2-weighted imaging, or susceptibility-weighted imaging (SWI); however, ASL revealed markedly increased blood flow to the left hemisphere. Subsequently, the rapid elevation of serum lactate dehydrogenase (LDH) and soluble interleukin-2 receptor (sIL-2R) levels after admission led to the diagnosis of IVLBCL by random skin biopsy and bone marrow examination. Despite the initiation of chemotherapy, the patient developed tumor lysis syndrome and succumbed to multiple organ failure. This case underscores the importance of considering IVLBCL in adult patients with refractory seizures and highlights the potential utility of ASL on MRI for early diagnosis.