Right vertebral artery entering the third transverse foramen diagnosed by magnetic resonance angiography: a report of two cases

Changes of Short-Term Heart Rate Variability and Vertebral Artery Magnetic Resonance Angiography in Patients with Cervical Vertigo

Cervical vertigo refers to a clinical syndrome with sudden vertigo as the main symptom caused by the hemodynamic disturbance of the extracranial segment of the vertebral artery (VA) affected by cervical vertebral lesions. Small differences in pulse intervals in a patient's continuous sinus rhythm are called heart rate variability (HRV). Heart rate variability refers to the small rise and fall of instantaneous heart rate between consecutive beats and is one of the most important physiological indicators of cardiac function. Small changes between successive beats reflect some information about the heart. So, it can be used to diagnose heart disease; its parameters can be used to identify emotions. Therefore, it is possible to use the characteristics of heart rate variability to find some patterns in the high-stress state and use the computer and ECG signals to describe the high-stress state. Since the ECG signal is a universal and objective model, it is practical and convenient to use it to describe stress states. Magnetic resonance angiography (MR angiography, MRA) is a noninvasive vascular imaging method that does not require intubation and contrast agents. At present, it has been widely used in clinical practice. In order to explore the changes of short-term heart rate variability and vertebral arterial magnetic resonance angiography (MRA) in patients with cervical vertigo and their clinical significance, this paper introduces two basic analysis methods of heart rate variability and commonly used MRA techniques, TOF technology. In the analysis of heart rate variability in patients with cervical vertigo, the statistical values of time and spectrum domain parameters were found to be lower in the experimental group than in the control group1. MRA showed that the abnormal rate of VA in the PCI group and the cervical vertigo group was similar. In the RMSSD index, the male experimental group reached 29, and the control group 1 reached 22.

Right vertebral artery arising from the right common carotid artery without association with an aberrant right subclavian artery and entering the C3 transverse foramen

The right vertebral artery (VA) rarely arises from the right common carotid artery (CCA); however, the majority of anomalous right VAs are seen in combination with an aberrant right subclavian artery (SA). Independent (or isolated) right VA of the right CCA origin is extremely rare, with only a few cases reported previously. We herein report an additional case diagnosed incidentally using computed tomography angiography. This patient had a left VA arising from the aortic arch between the origins of the left CCA and left SA. The bilateral VAs took an anterior course and entered the C3 transverse foramina, at an extremely high level.

Variations of the extracranial segment of vertebral artery as a bleeding risk factor

BACKGROUND

Standart interventional procedures such as screw instrumentation, aortic arch endovascular surgery and cervical nerve blockade may be of fatal risk due to anatomic reason of variations in the proximal part of the vertebral artery (VA). The aim of this study is to study the VA variations of the extracranial segments to evaluate the frequency of the incident to demonstrate the importance of clinical condition strategy.

METHODS

The prevalence of variations and morphometric measurements of the VA in three-dimensional computed tomographic angiography (3D-CTA) scans were studied. Total 400 VA was investigated for the aortic arch origin of the VA, diameter of the VA, its level of entry into the transverse foramen, the dominance sides, and related basilar artery course.

RESULTS

3D-CTA radiographs of 200 Anatolian patients (120 men and 80 women with age range 17-90 years). In most cases (approximately 94%), both sides of VA were the first branch of subclavian artery. While all the right VAs was branched from the subclavian artery, 6% of the left VAs were branched from the aortic arch. 2/3 of them originated from the proximal of the subclavian artery and 1/3 from the distal. The VA which were originating from the proximal of the classical anatomic pattern tended to enter the transverse foramen more distally than C6 level. VAs with a different level of entry than C6 are left-sided and aortic arch originated (out of 8 cases 3 had a level of entry at C5 and 2 at C4). The outer diameter ranges of the prevertebral part of the VA of subclavian origin and left VA of aortic arch origin were 3.2-3.6 mm and 3.2-3.6 mm, respectively. While the diameters of the right and left VAs were almost the same in approximately 20% cases, the left VA was dominant in up to 60% of cases. A significant relationship was found between the side of the dominant VA and in the course of the basilar artery.

CONCLUSIONS

The relationship between the dominant side of VA and the course of the basilar artery of its own vessel has never been reported elsewhere. Such anatomical variations, routine preoperative 3D-CTA evaluation is mandatory to prevent the VA injury when C5-C2 instrumentation, anterior cervical decompression, cervical nerve blockade and aortic arch surgery are planned.