Skull base closure systems and methods

A bioresorbable foam closure device for trans-nasally closing an opening in a base of a skull, the device comprising:

• a stem portion having a proximal end and a distal end, the stem having a first diameter;
• and
• a head portion at the distal end having a second diameter being larger than the first diameter;
• wherein the head portion comprises a film layer and a foam base, wherein a porosity of the film layer is greater than a porosity of the foam base;
• wherein the film layer is disposed at a distal end of the closure device and the foam base of the head portion is disposed between the film layer and the stem portion;
• wherein the head portion and the stem portion individually comprise a phase-separated polymer having an amorphous segment and a crystalline segment, and
• wherein the closure device is deformed from a free shape to a constricted shape, inserted through a nasal cavity and into the opening, and released to at least partially revert back to the free shape such that the stem portion fills the opening and the head portion abuts an inner surface of the skull as well as dura, thereby securing the closure device in position and sealing the opening.