How to conditionally hide field in Salesforce?

Hello all,

Need help for below requirement.

In Case object I have one custom field(Text) say Description and have another field say Private(Checkbox).

When user create any case and mark Private as Checked (Checkbox) then Description field should be visible to only the Owner of the case (creator of  the cecord) and the users who are upward in the role hierarchy, and other users won't be able to see this field.

How we can achieve this? any idea?

PS: I have already checked using Record type and different page layout.

Thanks in advance, every help is appreciated.