Which condition should be suspected if a patient presents with involuntary eye movements?

Involuntary eye movements are typically characteristic of nystagmus, which refers to a condition where the eyes make repetitive, uncontrolled movements. This can manifest as either horizontal, vertical, or rotational movements and may occur during certain head positions or in response to changes in visual stimuli.

Nystagmus can be an indicator of various underlying conditions such as vestibular disorders, neurological issues, or even side effects from medications. Recognizing nystagmus is crucial in clinical settings as it guides further diagnostic evaluation and treatment options.

While exophthalmos relates to the protrusion of the eyeball and strabismus involves the misalignment of the eyes, these conditions do not primarily present with the lack of control over eye movements. Diplopia, or double vision, can occur due to a variety of reasons, but it does not specifically describe involuntary movements of the eyes like nystagmus does. Therefore, the presence of involuntary eye movements directly points to nystagmus as the condition to suspect.