Lamina Papyrecea

The lamina papyracea is a paper thin portion of the ethmoid bone that constitutes the weakest portion of the medial orbital wall. Fractures of the lamina papyracea can be of the blow-in or blow-out variety. Both types can result in orbital emphysema and medial rectus entrapment resulting in diplopia. Blowout fractures result in herniation of intraorbital contents into the ethmoid sinus and occur frequently with orbital floor fractures.

Scrollable Stack Images

Images show a defect in the lamina papyrecea with herniation of intraorbital fat into the left ethmoid sinus. A portion of the left medial rectus muscle herniates into the defect, resulting in bowing of the muscle. Preseptal emphysema can be appreciated. The globe is intact and no other fractures are seen.

Static 2D


Click to enlarge

Static 3D


Click to enlarge

Rotating 3D

Return to top

Coronal image demonstrates fat and a portion of the left medial rectus muscle herniating into the ethmoid sinus.

Return to top

A slightly more anterior coronal image demonstrates the bony defect in the left lamina papyrecea with herniation of intraorbital fat into the left ethmoid sinus.

Return to top

Axial image demonstrates displacement of the left lamina papyrecea into the ethmoid sinus. Extensive preseptal emphysema can be appreciated.