RESUMEN
Aortic arch (AA) anomalies occur in approximately 3-5% of cadavers, but these atypical branches remain a point of discussion in cervical region surgery. This case report describes a 73-year-old Caucasian female who died of renal failure following a complicated urinary tract infection whose left vertebral artery (LVA) originated from the AA between the left common carotid and subclavian arteries. The preforaminal part of the LVA was 5 mm in diameter and entered the C6 transverse foramen while the right vertebral artery (RVA) arose from the right subclavian was 6.5 mm in diameter and entered the C5. Embryologically, VAs are formed during weeks four through eight by development of longitudinal anastomoses linking the cervical intersegmental arteries (ISA). The ISA regress except the seventh, which becomes the proximal subclavian artery, the point of origin of the adult VA. Persons with LVA that arises from the AA may be asymptomatic; however, secondary dilatation of the RVA may be implicated in the development of cerebrovascular disorders and atherosclerotic changes due to increased blood flow. Additionally, the anatomical positioning of a left vertebral artery is important when considering an anterior approach for cervical spine surgery and other head-neck procedures when soft structures arteries, veins and muscles are retracted to reach the cervical spine.
RESUMEN
We report a very rare case of cervical compressive myelopathy by an anomalous bilateral vertebral artery (VA) entering the spinal canal at the C1 level and compressing the spinal cord. A 70-year-old woman had been suffering from progressive gait disturbance. Magnetic resonance imaging revealed that a bilateral VA at the V4 segment had abnormal courses and caused compression to the high cervical cord. VA repositioning was performed by anchoring a suture between the artery and around the arachnoid membrane and dentate ligament, and then, microvascular decompression using a Teflon sponge was done between the VA and the spinal cord. The weakness in the patient improved in the lower extremity after the operation. Anomalous VA could be one of the rare causes of cervical compressive myelopathy. Additionally, an anchoring suture and microvascular decompression around the VA could be a sufficient and safe method to indirectly decompress the spinal canal.