NODI parameters ODI and V-ISO differentiate gliomas from brain metastases in contrast-enhancing regions

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AJNR. American journal of neuroradiology Published June 9, 2026 Medically reviewed June 9, 2026 Study authors: Ahmadzadeh Amir Mahmoud, Lomer Nima Broomand, Ghaderi Sadegh, Sani Mahdi Afarideh, Bathla Girish, Tu… PubMed ↗ DOI ↗ By Dr. Lars van Dijk, PhD · Surgical, Procedural & Diagnostic

Key Takeaway

Note that NODI parameters ODI and V-ISO can help differentiate gliomas from brain metastases in contrast-enhancing regions.

This meta-analysis evaluates the utility of Neurite orientation dispersion and density imaging (NODDI) parameters, specifically V-IC, V-ISO, and ODI, for differentiating gliomas from brain metastases (BMs). The analysis synthesized data from 10 studies to compare these metrics across different tumor types.

The results indicate significant differences in the contrast-enhancing regions. Specifically, the orientation dispersion index (ODI) was significantly lower in gliomas compared to BMs (effect size -1.43; 95% CI [-2.02, -0.85]). Additionally, the isotropic volume fraction (V-ISO) was significantly lower in gliomas than in BMs (effect size -0.98; 95% CI [-1.60, -0.37]). In a glioblastoma subgroup, V-ISO of the peritumoral edema area was also significantly lower in gliomas compared to BMs (effect size -0.73; 95% CI [-0.96, -0.50]).

The authors note that the study is limited by a small number of included studies. Despite these limitations, the findings suggest that NODDI parameters, particularly ODI and V-ISO, may be useful tools for clinical differentiation between gliomas and brain metastases. Clinical application should consider the current evidence base and the specific characteristics of the imaging cohort.

Study Details

Study typeMeta analysis

EvidenceLevel 1

PublishedJun 2026

PMID41412743

View Original Abstract ↓

BACKGROUND: Differentiation between gliomas and brain metastases (BMs) remains a diagnostic challenge. Noninvasive imaging biomarkers could be advantageous in brain tumor discrimination. PURPOSE: We aimed to systematically review the studies that measured neurite orientation dispersion and density imaging (NODDI) parameters in patients with gliomas and BMs. DATA SOURCES: A literature search was conducted in 4 databases, including PubMed, Web of Science, EMBASE, and Scopus. STUDY SELECTION: Studies that measured NODDI parameters, such as intracellular volume fraction (V-IC), isotropic volume fraction (V-ISO), and orientation dispersion index (ODI) in both patients with glioma and patients with BM were included. DATA ANALYSIS: Quality was assessed using the modified Newcastle-Ottawa Scale checklist. Pooled standardized mean differences (SMDs) with corresponding 95% CIs were calculated using a random-effects model. Heterogeneity was evaluated using the statistic. Subgroup analysis was performed to explore sources of heterogeneity. Funnel plots, along with Begg and Egger tests were applied to investigate publication bias. DATA SYNTHESIS: Ten studies were ultimately included in the systematic review. We found significant SMDs for ODI (SMD = -1.43 [-2.02, -0.85]) and V-ISO (SMD = -0.98 [-1.60, -0.37]) between gliomas and BMs in the contrast-enhancing region. Also, for the glioblastoma subgroup, V-ISO of the peritumoral edema area showed a significant SMD (SMD = -0.73 [-0.96, -0.50]). No significant differences were found for other parameters. The heterogeneity turned from high to low in specific subgroups, including the glioblastoma subgroup. LIMITATIONS: Our meta-analysis is limited by small number of studies. CONCLUSIONS: NODDI parameters, particularly ODI and V-ISO, can be considered useful tools for differentiating gliomas from BMs. These findings highlight the potential of NODDI as a noninvasive imaging biomarker to improve the differential diagnosis of intracranial tumors.