Читать книгу Anatomy for the Royal College of Radiologists Fellowship - Malcolm Sperrin - Страница 13

1 Name the arrowed structure.

2 Name the arrowed structure.

3 Name the arrowed structure.

4 Name the arrowed structure.

5 Name the arrowed structure.

Answers

1 Straight sinus.

2 Posterior arch of C1 (atlas).

3 Tectorial membrane.

4 Basilar artery.

5 Internal cerebral vein.

Comments:

The superior sagittal sinus meets the right and left transverse sinuses at the confluence of the sinuses (torcular herophili). The transverse sinuses become the sigmoid sinuses, which leave the skull base through the jugular foramen to form the internal jugular veins. The sigmoid sinus becomes the internal jugular vein when it is joined by the inferior petrosal sinus in the jugular foramen.

The right and left basal veins of Rosenthal join with the internal cerebral veins to form the vein of Galen, which is short and runs within the quadrigeminal cistern. This then combines with the inferior sagittal sinus to form the straight sinus, which drains into the confluence of the sinuses.

The tectorial membrane is continuous with the posterior longitudinal ligament of the spine, and passes from the posterior body of C2, along the posterior odontoid process, to the clivus.

Exam tips:

 Remember that even though the phase of contrast is venous, arterial structures (such as the basilar artery in this case) may still be discernible, and vice versa.

 In most cases in the exam, if the structure shown is paired, then you should include left or right in your answer. In some cases, however, it isn’t possible to tell (as with the internal cerebral vein here)—in that case, just give the name of the structure without including laterality.