Related Experiment Video
Updated: Dec 23, 2025

Author Spotlight: A Reproducible and Efficient Method for Accessing Porcine Brain via Craniectomy
Published on: July 5, 2024
Massive Ossification with Hematopoietic Marrow on Both Surfaces of the Expanded Polytetrafluoroethylene Artificial
Naoki Maehara1, Takato Morioka2, Takafumi Shimogawa3
1Department of Neurosurgery, Kyushu Rosai Hospital, Kitakyushu, Japan; Department of Neurosurgery, Graduate School of Medical Sciences, Kyusyu University, Fukuoka, Japan.
Background:
Artificial dural substitute made from an expanded polytetrafluoroethylene (ePTFE) sheet has been widely used in surgical application.
Case Description:
We describe a 19-year-old woman in whom massive ossification with hematopoietic marrow was noted on both surfaces of an ePTFE sheet during epilepsy surgery. At age 8, she underwent decompressive craniectomy for a ruptured arteriovenous malformation in the right frontal lobe, followed by duraplasty with an ePTFE sheet and autologous cranioplasty fixed with titanium miniplates.
Conclusions:
Since the ossification was prominent in the wrinkle dents of the ePTFE sheet and fibrotic membrane with repetitive hemorrhagic events was noted under the ePTFE sheet, the most plausible mechanism of ossification development is the organization of epiartificial and subartificial dural hematoma. Surgeons should be aware of the possibility of ossification development when working with ePTFE sheets for duraplasty.
Related Concept Videos
Cranial and Spinal Meninges
Cranial Meninges
These meningeal layers cover the cranium. The dura mater is the outermost layer of cranial meninges. It is a thick and durable membrane of dense...
Sutures of the Skull
Sutures are immobile joints between adjacent bones of the skull. The narrow gap between the bones is filled with dense, fibrous connective tissue that unites the bones. The long sutures located between the skull bones are not straight but instead follow irregular, tightly twisting paths. These twisting lines tightly...
Bone Formation by Intramembranous Ossification
The process begins when mesenchymal cells in the embryonic skeleton gather together and differentiate into osteogenic cells, which then develop into ...
Cranial Bones: Superior and Posterior View
The frontal bone is the single bone that forms the forehead. At its anterior midline, between the eyebrows, there is a slight depression called the glabella. The frontal bone also forms the supraorbital margin of the orbit. Near the middle of this margin is the supraorbital foramen, the opening that provides passage for a sensory nerve to the forehead. The frontal bone is thickened just above each supraorbital margin,...
Bone Formation by Endochondral Ossification

