What Causes Temporary Loss Of Peripheral Vision?

My inquiry is regarding my 18yr old daughter. Yesterday she experienced a temporary loss of her peripheral vision. Her only medical history is related to malabsorption due to what I believe is a gluten sensitivity, although she denies having problems with gluten. She will say milk hurts her stomach, but an elimination diet revealed at least a sensitivity to foods containing gluten, milk, HFCS and GMOs. She has worn corrective lenses since she was about 9 or 10. She phoned an eye doctor yesterday which referred her to a retina specialist. I guess my question is, is there any way of eliminating the possibility of retina detachment without spending $300 at the retina specialist? I don t have health insurance, and just became unemployed less than two weeks ago. I need to NOT spend hundreds of dollars figuring this out, but at the same time I do not want to put her eyesight in jeopardy.