What are the mechanisms of blurred vision which was part of his initial symptoms?

Read the following case study and answer the posed questions: Case 1: History: A 65 year old housewife complains of progressive weight gain of 40 pounds in 1 year, fatigue, dizziness, sluggish memory, slow speech, deepening of her voice, dry skin, constipation, and cold intolerance. Physical examination: Vital signs: temperature 96.4oF, pulse 68/minute and regular, […]