Migraine with Aura: This condition is characterized by visual disturbances such as spotty vision, loss of vision, and other neurological symptoms like dizziness. The visual symptoms can include blind spots, zigzag patterns, and temporary loss of vision, which align with the described symptoms.

Optic Neuritis: An inflammation of the optic nerve that can cause loss of vision, blind spots, and pain with eye movement. It might not directly cause dizziness but can lead to visual disturbances that could contribute to a feeling of instability.
Vitreous Detachment: A condition where the vitreous gel in the eye separates from the retina, causing floaters and flashes of light, which could be perceived as spotty vision. It might not directly cause dizziness but can lead to significant visual disturbances.
Macular Degeneration: A condition that affects the macula, the part of the eye responsible for central vision, leading to loss of central vision and difficulty with tasks like reading. While it doesn't typically cause dizziness, the significant visual disturbance could contribute to feelings of unsteadiness.

Stroke or Transient Ischemic Attack (TIA): Although less common, a stroke or TIA can present with sudden loss of vision, dizziness, and other neurological deficits. It's critical to rule out these conditions due to their high morbidity and mortality.
Giant Cell Arteritis: An inflammation of the blood vessels that can lead to sudden loss of vision and other systemic symptoms. It's a medical emergency that requires prompt treatment to prevent further vision loss.
Retinal Detachment: A condition where the retina separates from the back of the eye, causing sudden loss of vision, flashes of light, and floaters. It's an emergency that requires immediate medical attention to save vision.

Multiple Sclerosis: An autoimmune disease that can affect the optic nerve and brain, leading to a wide range of neurological symptoms including vision loss, dizziness, and difficulty with coordination and balance.
Occipital Lobe Seizures: Seizures that originate in the occipital lobe of the brain can cause visual disturbances, including loss of vision, blind spots, and formed visual hallucinations, along with other neurological symptoms.
Charles Bonnet Syndrome: A condition that occurs in people with significant vision loss, characterized by complex visual hallucinations. While it doesn't cause dizziness, it could be considered in the differential for spotty or altered vision in the context of existing visual impairment.