MRI location of the distal dural ring plane: anatomoradiological study and application to paraclinoid carotid artery aneurysms.
The distal dural ring plane (DDRP) separates the intradural from the extradural paraclinoid internal carotid artery. The purpose of this study was to evaluate its position with MR imaging. The protocol used a T2-weighted sequence in two orthogonal planes: diaphragmatic (DIA-P) and carotid (CAR-P). The DDRP passes through four anatomoradiological reference points (RefP). We developed on a cadaveric model a correlation method supported by correlation lines and angles (CA) projecting the RefP toward the DDRP. RefP were correlated to the DDRP in 65-84% of cases in the DIA-P and 60-76% of cases in the CAR-P. CA were identified and correlated to the DDRP, respectively, in 87% and 60% of cases in the DIA-P, and 60% and 51% of cases in the CAR-P (failure often related to a lack of visibility of just one RefP). A higher tissular contrast in living subjects allowed the identification of CA in 90% and 80% of cases, respectively, in the DIA-P and the CAR-P. We propose that CA, when identified, should be considered as an approximation of the inferior radiological limit of the DDRP curve. In difficult angiographical cases, this MRI protocol could help to locate paraclinoid aneurysms on both sides of the cavernous sinus roof.
Thines
Laurent
L
Department of Neurosurgery, University Hospital, Lille, France. Laurent.Thines@wanadoo.fr
Delmaire
Christine
C
Le Gars
Daniel
D
Pruvo
Jean-Pierre
JP
Lejeune
Jean-Paul
JP
Lehmann
Pierre
P
Francke
Jean-Paul
JP
D000328:Adult; D002343:Carotid Artery, Internal / Q000473:pathology*; D002533:Cerebral Angiography; D004388:Dura Mater / Q000473:pathology*; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D002532:Intracranial Aneurysm / Q000175:diagnosis*; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D008953:Models, Anatomic; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013223:Statistics as Topic