Diffusion Restriction in Wilson's Disease: A Radiological Pointer Toward Clinically Severe Disease

Wilson's disease (WD) is a rare autosomal recessive disorder due to abnormal hepatic copper transport, leading to copper accumulation in the liver, brain, and other tissues. Although conventional magnetic resonance imaging (MRI) features are valuable for diagnosis, the role of diffusion-weighted imaging (DWI) remains underexplored in WD. The study aims to assess the prevalence and clinical correlates of diffusion restriction on MRI in WD.

A single-center, retrospective study was conducted. Clinicodemographic and MRI findings of patients diagnosed with WD based on a modified Leipzig score cut-off of 4 were analyzed. Characteristics of patients with diffusion restriction (WD DR+ ) and without diffusion restriction (WD DR- ) were compared using statistical tests.

Of 91 patients with WD, 17 (18.7%) demonstrated MRI diffusion restriction. WD DR+ were noted to have a lower median age at symptom onset (14 [9-17] versus 15 [14-23] years; P = 0.020) and presentation (15 [13-20] years versus 19 [15-25.5] years; P = 0.022) compared to WD DR- . WD DR+ had a higher modified Leipzig score compared to WD DR- (5 [4-5] versus 7 [5-8]; P ≤ 0.001). They also had significantly higher Global Assessment Scale (GAS) for WD (32.5 [30-37]) compared to WD DR- (19 [13-22]) ( P < 0.001). WD DR+ had significantly higher proportions of patients with dysphagia (10/17, 58.8% versus 6/74, 8.1%; P < 0.001) and portal hypertension (8/17, 47.1% versus 6/74, 8.1%; P < 0.001). WD DR+ also experienced significantly higher rates of early neurological deterioration (END) (23.5% versus 6.6%, P = 0.04).

Diffusion restriction may hence serve as a pointer toward more severe neurological and hepatic involvement in WD, indicating the need for close supervision in this group of patients.