How long do oscillopsia and ataxia secondary to thiamine deficiency last after completing repletion?

I treated a patient with severe thiamine deficiency following bariatric surgery. I administered parenteral thiamine at a dose of 100 mg weekly. The diplopia resolved with the first infusion, but returned 5-6 days. She was continued on thiamine infusions weekly and her diplopia eventually resolved. It took several months to get her controlled on oral thiamine replenishment.