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Abstract Background Visual dysfunction is a common but underrecognized contributor to disability in Parkinson’s disease (PD), particularly deficits in binocular vision and vergence that impair reading, near work, and quality of life. The relationship between objective oculomotor abnormalities and patient⍰reported visual disability remains incompletely understood. Methods We studied 25 individuals with PD and 11 age⍰matched controls who completed the National Eye Institute Visual Function Questionnaire⍰25 (VFQ⍰25) and the Convergence Insufficiency Symptom Survey (CISS). Participants underwent comprehensive clinical ophthalmologic assessment and high⍰resolution binocular eye tracking to quantify vergence latency, gain, fixation dynamics, and drift variability. Associations between objective measures and patient⍰reported outcomes were examined, and predictive models were developed using clinic⍰only and combined clinic + eye⍰tracking approaches. Results Compared with controls, PD participants demonstrated significantly worse VFQ⍰25 composite scores and higher CISS scores, driven primarily by impairments in near activities and mental health. Clinically, PD was characterized by convergence insufficiency rather than generalized visual loss. Objective eye tracking revealed delayed vergence initiation, reduced gain, and increased instability. In PD, both clinical convergence measures (notably near⍰point convergence) and dynamic eye⍰tracking metrics strongly correlated with VFQ⍰25 and CISS scores, whereas such relationships were absent in controls. Predictive models showed limited performance using clinic measures alone, but improved with inclusion of eye⍰tracking variables. Conclusions Visual disability in PD is tightly linked to convergence insufficiency and dynamic oculomotor instability. Simple clinical measures such as near⍰point convergence, augmented by eye tracking when available, provide meaningful insight into patient⍰reported visual quality of life.