Inline skating as a possible cause of consecutive bilateral vertebral artery dissection

Dissection of the vertebral arteries following minor head and neck traumas due to sporting activities such as tennis, yoga and volley ball has been previously reported (1±3). We report on a case of a 41-year-old female patient who was admitted with increasing left-sided neck pain since 4 days. She did not report any fall or other trauma. However, she performed on the day of acute onset of symptoms inline skating for about 2 h. Neurological examination at admission was otherwise unremarkable. MRI of the brain showed no pathological ®ndings. Duplex scan revealed normal frequency spectra and a normal ̄ow velocity in the right vertebral artery and a high resistance ̄ow pro®le in the left vertebral artery. In addition to the clinical features these ®ndings were considered as highly suspicious for a dissection of the left vertebral artery. MR-angiography disclosed a small vessel lumen with severe narrowing proximal to and along the atlas slope of the left vertebral artery, but no evidence of a dissection. With respect to the clinically suggestive presentation conventional supraaortic angiography was performed and disclosed occlusion of the left vertebral artery cranial to the origin of the posterior inferior cerebellar artery. The distal parts of the vertebral artery were ®lled retrograde by the right vertebral artery, which showed no abnormalities. To prevent further thrombus formation treatment with intravenous heparin was established. Follow-up MRangiography 1 week later demonstrated concentric wall thickening of the left vertebral artery characteristic for a dissection of the vessel wall. On day 9 after admission the patient developed horizontal nystagmus and transient right sided homonymous hemianopsy. Five days later the patient complained of severe neck pain on the right side. Duplex scan demonstrated dissection of the right vertebral artery revealing an extending intimal ̄ap in the right vertebral artery. At this time MRI showed small bilateral medullar infarctions whereas an eccentric crescent high signal intensity representing intramural hemorrhage surrounded the left vertebral artery at the mastoid slope and con®rmed the diagnosis of dissection. MR-angiography disclosed patency of the left vertebral artery without residual lumen narrowing or thrombi. However, in the right vertebral artery an extensive dissection with subtotal lumen obstruction was detected. Therapy with intravenous heparin was proceeded. The patient recovered completely and was discharged without any neurological symptoms on oral anticoagulants. MRI performed 4 weeks after the primary event con®rmed persisting dissection of the right vertebral artery with subtotal stenosis and patency of the left vertebral artery without lumen narrowing. Clinical examination 6 months after discharge showed the patient free from neurological symptoms. In this case the ®rst dissection may have been caused by excessive tension of the neck muscles during inline skating. Any fall or macrotrauma as well as abrupt or uncontrolled head movements during skating were denied by the patient. The excessive tension of the neck muscles in the rather untrained woman may have resulted in a small intimal tear which consecutively led to a false lumen of blood within the media. However, the second dissection occurred 2 weeks later during bed rest. It may be speculated that a small tear in the vessel wall was increased by a microtrauma due to coughing or nose blowing and led to the delayed manifestation of the dissection of the right vertebral artery. The interval between the onset of neck pain indicating the initiation of dissection and the ischemic event was 14 days. This is in accordance with reports by Hinse et al. (4) and Mas et al. (5) that pain is preceding neurological symptoms of basilar ischemia for few minutes to 6 weeks. Duplex scan and clinical ®ndings established the diagnosis. The initial dissection was localized in the V3 segment of the left vertebral artery. Diagnosis by color-coded duplex scan was based on indirect signs in the midcervical course showing a high resistance ̄ow pro®le with an increased Acta Neurol Scand 2000: 101: 70±71 Printed in UK. All rights reserved Copyright # Munksgaard 2000