Can sinusitis cause blurred vision and sensitivity to light?

Sinusitis: No. You may have one of the major but rare complications of sinusitis with extension of infection into the central nervous system, either as a brain abscess or other infection of the spaces created by the linings of the brain. You should be seen immediately by a doctor and will probably undergo emergency imaging studies and consultation with an ophthalmologist and possibly an infect dis expert.

Unlikely: Typically sinusitis does not cause blurry vision or sensitivity to light. There are other things that can cause these symptoms such as inflammation in the eye (uveitis), dry eyes, or eye infection. You should see your eye doctor for evaluation. In the mean time, use artificial tears to lubricate the eyes.