Of these 27 TGA patients, the presence of a vicarious shunt with posterior condylar collateral formation was found in 15 (55.6%) TGA patients in contrast to 8.9% in controls, while in 13 (48.1%) patients the contrast refluxed into the IJV (Fig 1Bd ), or refluxed directly through intrarachidian anastomoses to the contralateral side at a different level (Fig 1Be ).
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