DX: Left Carotid Artery Loop or Coil. Vertebral artery artifact

Though this case is incomplete and had technical deficiencies (such as: 1 Tesla Magnet; TOF sequence; no arteriogram; and lack of showing aortic arch and carotid and subclavian proximal segments). All of this issues makes diagnosis a little difficult.

First of all, TOF sequence itself always has its ups and downs because of low sensitivity. In addition, 3D reconstruction predisposes more artifacts. Many of these artifacts can cause pseudostenosis or segmental blurring. This has to be expected when looking at this sequence. To be assured, lets see the raw data previous 3D reformat.

There is an irregular trajectory of the left carotid artery in the upper cervical portion previous to petrous segment. This makes the diagnosis of a Carotid "Loop" more plausible. Clinical symptoms support this posibility. On the other hand, we did not see an abnormal left vertebral artery, that was shown in the 3D virtual reconstruction.

In this case, and arteriogram had to be done so it was reffered to another institution. (Finantial issues).

Carotid Loop or Coil:

The association between kinking or coiling of the internal carotid artery (ICA) and cerebrovascular insufficiency was first noted in 1951. Since then several reports have dealt with the clinical relationship between carotid elongation and kinking and cerebrovascular disease. Although conclusive evidence linking the two is still lacking, certain inferences can now be drawn.

Looping and kinking of the ICA has been observed in infants and even in fetuses. The cause of these loops is related to embryological development. The vessel is formed from the third aortic arch and from the dorsal aorta; hence, in the embryo it is normally kinked.
Straightening occurs when the fetal heart and large vessels recede in the thoracic cavity. If the embryological state persists, it produces different kinds of undulations, loops, and kinks. This anomaly generally does not become symptomatic until later in life.

There appears to be no relationship between the severity of the kinking and either rising blood pressure or increasing age. The role of degenerative changes in the vessel wall remains uncertain. If this factor were important, then kinks should be more severe in older individuals because degenerative changes increase with age; however, this is not generally the case. At best the cause for looping and kinking of the carotid artery may be ascribed partly to embryological development and partly as secondary to atherosclerotic changes.

http://www.crcnetbase.com/doi/abs/10.1201/9780203912904.ch54
http://stroke.ahajournals.org/content/6/6/649.full.pdf
http://bubbasoft.org/carotid_collaterals/carotid_loops.htm


All coments are welcome...have a nice day.