Brief Answer:
Retinal detachment suspected, emergency condition

Detailed Answer:
Hello dear,

Thanks for your query.

In your post, you have not mentioned about any history of trauma to the eyes, past history of systemic illness like Hypertension, Diabetes, etc. or any history of recent or prolonged medicine intake by your husband.

Under such circumstances, painless and sudden onset of blurring of vision can be attributed to Retinal detachment.
Varying of blurriness with movement of head is characteristic of it.
This is an emergency condition and if proper corrective measures are not taken on time, may lead to permanent loss of vision in the eye.

Clinical examination is important for diagnosis, so I will advise you to consult your Doctor/ Ophthalmologist at the earliest.
Fundoscopic examination will be helpful in clinching the diagnosis and taking appropriate management steps.

There is no need to worry, he will be fine.
Wish your husband good health & a speedy recovery.
Take care.

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