The ELANA technique involves a platinum ring. A 2.6 and a 2.8 mm ring are enclosed in the Elana Surgical Kit. Therefore, the smallest possible recipient artery has a diameter of approximately 2.5 mm. Smaller arteries than this size are more peripheral in the brain. They tolerate temporary occlusion time because of intracerebral and leptomeningeal collaterals (these are ‘natural’ bypasses already existing in the human brain). Therefore on these vessels a conventional anastomosis instead of an ELANA is possible.
This picture indicates the possible ELANA anastomosis locations in the brain.
The ELANA site has to be free of arteriosclerotic plaques or any other vessel wall disease.
Figure: Schematic overview of the proximal arterial vasculature of the brain. Possible area for an ELANA anastomosis is indicated in blue. Abbreviations (left to right, top-down): RMCA, Right Middle Cerebral Artery; RACA, Right Anterior Cerebral Artery; LACA, Left Anterior Cerebral Artery; LMCA, Left Middle Cerebral Artery; PCOMS, Posterior Communicating Arteries; RPCA, Right Posterior Cerebral Artery; LPCA, Left Posterior Cerebral Artery; RICA, Right Internal Carotid Artery; BA, Basilar Artery; LICA, Left Internal Carotid Artery; RCCA, Right Common Carotid Artery; RVA, Right Vertebral Artery; LVA, Left Vertebral Artery; LCCA, Left Common Carotid Artery.
Currently, also other possible recipient places inside and outside the skull are under investigation.