Background: The aim of the current study was to analyse the extra- and intracerebral course of the recurrent artery of Heubner (RAH) to provide detailed information for neurosurgeons operating in this area.

Materials and methods: The material for this study was obtained from cadavers (ages 31–75 years) during routine autopsies. A total of 70 human brains (39 male and 31 female) were examined. The material was collected not later than 48 h post-mortem. People who died due to neurological disorders were not includedinto the study. Right after dissection the arteries were perfused with either acrylicpaint emulsion, polyvinyl chloride or Mercox CL-2R resin, through the Circle ofWillis or electively through the RAH. The obtained material was analysed usinga stereoscopic light microscope, magnification 2–40´.

Results: The RAH was present in 138 hemispheres with a mean of 1.99 RAH per hemisphere (275 RAH in total). The mean RAH length was 25.2 mm and the mean RAH diameter, in its place of origin, was 1 mm. In 168 (61%) cases the RAH ran superiorly, in 88 (32%) cases anteriorly, in 11 (4%) cases inferiorly and in 8 (3%) cases posteriorlyto the A1 segment. In 70.2% of the cases the course of the RAH was parallel to theanterior communicating artery A1 segment, and in 29.8% of the cases the RAH archedtowards the olfactory tract. As the extracerebral course of the RAH was always tortuous,its length was 1 to 5 times the distance between its place of origin and the most lateralpoint of anterior perforated substance (APS) penetration. The intracerebral course ofthe RAH was almost always univectorial — towards the head of the caudate nucleus.The course of RAH branches depended on their number. When the number of RAH sand their branches was low, they separated immediately after penetrating the APS andformed multiple small branches. When the number of RAHs and branches was high,post-APS branching was less frequent and occurred in distal segments.Conclusions: The origin and course of the RAH is highly variable. The RAH, in itsextra- and intracerebral course, may join with the middle group of the lenticulostriatearteries or directly with the middle cerebral artery. This artery should beroutinely identified during anterior communicating artery aneurysm clipping toprevent postoperative neurological deficits.