US Patent 11445901 One-time use expandable speculum

Expandable specula devices and methods are disclosed. In one aspect, a speculum includes inner and outer balloon layers configured to expand circumferentially. The inner and outer balloon layers form a sealed cavity configured to hold a liquid. The speculum further includes an access tube for injecting the liquid into the cavity. The speculum further includes a shape memory alloy layer within the outer balloon layer. The shape memory alloy layer is configured to transition to a first shape when heated above a transition temperature.