Learning objectives
Numerous canals and foramina of the skull base are unknown and not familiar to general radiologists
Our objectives is to review the anatomy of the "forgotten" foramina of the skull base and their contents,
demonstrate the visibility of these foramina in high resolution CT images,
study their location and spatial relationships and provide examples of pathological process affecting these structures.
Background
For the study of these structures we have high resolution images from a 16 channel multidetector CT scanner in axial,
sagittal and coronal planes.
0,6 millimeters slices of routine CT head scans,
and an advantage workstation GE 4.4 for post-processing are used to study normal CT anatomy of these foramina.
We view the slices using a high resolution reconstruction algorithm and bone windowing.
We study ten structures: anterior and posterior ethmoidal canals,
foramen venosum,
craniopharyngeal canal,
canalis basilaris medianus,
petromastoidal canal,
posterior condylar canal,
palatovaginal...
Findings and procedure details
Anterior and posterior ethmoidal canals:
The anterior and the posterior ethmoidal canals (AEC and PEC) ( Fig. 1 and Fig. 2 ) are lateral toeither olfactory groove.
The AEC transmits the anterior ethmoidal artery,
vein and nerve.
The PEC transmits the posterior artery,
vein and nerve.
[1,
2,
3,
4]
The anterior ethmoidal artery (AEA) crosses three cavities: the orbit,
the ethmoid labyrinth and the anterior fossa of the skull (Fig. 1) .
This artery irrigates the anterior ethmoidal cells and the frontal sinus; it...
Conclusion
Conclusion:
Knowledge of rare and unfamiliar foramina of the skull base is important in head and neck radiology to recognize the pathologic process affecting these structures and to differentiate canals and fractures.
References
References
1.
Souza SA,
Souza MM,
Gregório LC,
Ajzen S.
Anterior ethmoidal artery evaluation on coronal CT scans.
Braz J Otorhinolaryngol.
2009 Jan-Feb; 75(1):101-6.
2.
Riehm S,
Pénisson L,
Charpiot A,
Schultz P,
Veillon F,
Debry C.
CT imaging of the anterior ethmoidal artery: anatomic correlation.
J Radiol.
2008 Feb;89(2):229-33.
3.
Pandolfo I,
Vinci S,
Salamone I,
Granata F,
Mazziotti S.
Evaluation of the anterior ethmoidal artery by 3D dual volume rotational digital subtraction angiography and native multidetector CT with multiplanar reformations.
Initial findings.
Eur...