The diploic venous system: surgical anatomy and neurosurgical implications.
OBJECTIVE
There are few systematic investigations of the dissected surgical anatomy of the diploic venous system (DVS) in the neuroanatomical literature. The authors describe the DVS relative to different common neurosurgical approaches. Knowledge of this system can help avoid potential sources of unacceptable bleeding and may impact healing of the cranium.


METHODS
Using a high-speed drill with a 2-mm bit, the authors removed the outer layer of the compact bone in the skull to expose the DVS in 12 formalin-fixed cadaver heads. Pterional, supraorbital, and modified orbitozygomatic craniotomies were performed to delineate the relationship of the DVS.


RESULTS
The draining point of the frontal diploic vein (FDV) was located near the supraorbital notch. The draining point of the anterior temporal diploic vein (ATDV) was located in all pterional areas; the draining point of the posterior temporal diploic vein (PTDV) was located in all asterional areas. The PTDV was the dominant diploic vessel in all sides. The FDV and ATDV could be damaged during supraorbital, modified orbitozygomatic, and pterional craniotomies. The anterior DVS connected with the sphenoparietal and superior sagittal sinus (SSS). The posterior DVS connected with the transverse and sigmoid sinuses and was the dominant diploic vessel in all 24 sides. Of all the major diploic vessels, the location and pattern of distribution of the FDV were the most constant. The parietal bone contained the most diploic vessels. No diploic veins were found in the area delimited by the temporal squama.


CONCLUSIONS
The pterional, orbitozygomatic, and supraorbital approaches place the FDV and ATDV at risk. The major anterior diploic system connects the SSS with the sphenoparietal sinus. The posterior diploic system connects the SSS with the transverse and sigmoid sinuses.
García-González
Ulises
U
Divisions of Neurological Surgery, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, Arizona, USA.
Cavalcanti
Daniel D
DD
Agrawal
Abhishek
A
Gonzalez
L Fernando
LF
Wallace
Robert C
RC
Spetzler
Robert F
RF
Preul
Mark C
MC
D002102:Cadaver; D002426:Cavernous Sinus / Q000033:anatomy & histology; D002550:Cerebral Veins / Q000033:anatomy & histology; D003399:Craniotomy / Q000379:methods; D004388:Dura Mater / Q000033:anatomy & histology / Q000098:blood supply; D006801:Humans; D019635:Neurosurgical Procedures / Q000379:methods*; D010294:Parietal Bone / Q000098:blood supply; D012886:Skull / Q000033:anatomy & histology / Q000098:blood supply*; D054063:Superior Sagittal Sinus / Q000033:anatomy & histology; D013701:Temporal Bone / Q000098:blood supply; D014680:Veins / Q000033:anatomy & histology* / Q000601:surgery