OBJECTIVE To evaluate Wilson's disease (WD) features in Sardinian patients with Kayser-Fleischer (KF) ring and to evaluate correlations between modifications in KF and anti-copper therapy and systemic WD evolution. METHODS Sixty-seven WD patients (35 m/32 f; mean age 41 years) were retrospectively studied. At diagnosis and during follow up comprehensive ophthalmologic and neurologic examinations, brain RMN and ECD SPECT, detailed objective laboratory studies and hepatic histological examination were performed on all patients for analysis. All patients were given anti-copper therapy with d-Penicillamine in mono-therapy or in combination with Zinc Salts. RESULTS At diagnosis, KF was observed in 27% of patients with equal distribution in all age groups. Significant correlations between KF at diagnosis, neuro-psychiatric manifestations and pathologic features in brain RMN and in brain ECD SPECT were found at diagnosis. During follow up, a decrease in, or regression of KF was seen in 14% of patients. Anti-copper therapy leads to KF regression and prevents the appearance of KF. No significant correlations were observed between KF regression and clinical neurological or neuro-imaging improvement nor between KF modifications and clinical hepatic improvement. CONCLUSIONS Our study highlights the peculiar features of Sardinian WD patients: low representation of KF, its equal distribution in all age groups, significant correlation between KF at diagnosis and clinical neurological manifestations, pathologic brain RMN and brain ECD-SPECT are highlighted by our study. Anti-copper therapy induces KF regression and prevents its onset. Therefore, KF ring does appear to be a predictive factor in the neurological and hepatic evolution of WD.