Variations of the aortic arch - a study on the most common branching patterns.

BACKGROUND: Anatomical variants of the aortic arch and its branching patterns often appear as an incidental finding during routine computed tomography (CT) scanning. These variations can be of relevance when performing angiography or endovascular interventions and may cause symptoms such as dysphagia. PURPOSE: To analyze common anatomical variations found within the arteries originating from the aortic arch in patients using contrast CT imaging techniques. MATERIAL AND METHODS: A total of 2033 contrast CT scans were analyzed. To obtain a truly representative sample, cases were chosen from different hospital departments without previous knowledge of the patient history. RESULTS: The total percentage of variations within the analyzed patients was 13.3%. In 8.0% a truncus bicaroticus was found. 4.2% of the patients showed a left vertebral artery originating directly from the aortic arch, mostly proximal, and in 1 case distal to the left subclavian artery. In 1.0% we found an aberrant right subclavian artery. We also found a single case of a right descending aortic arch. CONCLUSION: Variations of the aortic arch and its branching are frequently found, mostly as an incidental finding during routine diagnostic scanning. A contrast-enhanced CT scan is a good method with which to study the aortic arch and its associated branching pattern.

Dynamic visualization of arachnoid adhesions in a patient with idiopathic syringomyelia using high-resolution cine magnetic resonance imaging at 3T.

A 39-year-old female patient with thoracic syringomyelia underwent routine magnetic resonance imaging (MRI) and 3 T MRI to investigate the value of retrospectively cardiac-gated cine steady-state free precession (SSFP) MRI in the preoperative and postoperative diagnosis of arachnoid membranes in the spinal subarachnoid space. Therefore, 3T MRI included sagittal and transverse retrospectively cardiac-gated cine balanced fast-field echo (balanced-FFE) sequences both preoperatively and after microsurgical lysis of arachnoid adhesions and expansive duraplasty. Arachnoid membranes were detected and this result was correlated with intraoperative findings and the results of routine cardiac-gated phase-contrast cerebrospinal fluid (CSF) flow MRI. Retrospectively cardiac-gated cine SSFP MRI enabled imaging of arachnoid membranes with high spatial resolution and sufficient contrast to delineate them from hyperintense CSF preoperatively and postoperatively. The images were largely unaffected by artifacts. Surgery confirmed the presence of arachnoid adhesions in the upper thoracic spine. Not all arachnoid membranes that were seen on cine balanced-FFE sequences caused significant spinal CSF flow blockages in cardiac-gated phase-contrast CSF flow studies. In conclusion, retrospectively cardiac-gated cine SSFP MRI may become a valuable tool for the preoperative detection of arachnoid adhesions and the postoperative evaluation of microsurgical adhesiolysis in patients with idiopathic syringomyelia.