Questions about possible blindness from high blood pressure

At my 11-year-old cat’s annual exam they noticed her pupils were both huge and asked me if she’s blind. I said no, she’s terrified. She hates going to the vet. She had started not grooming herself recently and her coat wasn’t as nice as usual and she’d lost about a pound in weight. The vet suspected hyperthyroidism. They did a senior blood panel and told me her liver enzymes are high but everything else is normal, including thyroid. I took her back to have blood work done 45 days later and her liver enzymes were still high with everything else normal. They also checked her blood pressure at my request and it was very high at 240-250 range. The vet is not an ophthalmologist but said she thinks my cat has very poor vision. We started her on blood pressure medication and are not treating the liver issue because she has no other symptoms. At home indoors her pupils are often large but outside in brighter light they’re small/tiny. They’re always both the same size. She seems like she can’t see well, but it’s really hard to tell! If a cat loses vision from high blood pressure, do their pupils still get large in low light and small in bright light? And are the pupils always both the same? One day my cat was outside with huge pupils and as I walked closer to her suddenly her pupils were small but she hadn’t moved. Is that normal?