Axial section of the medulla at the level of the olive and the fourth ventricle, just rostral to the central canal

An area of infarction is evident in the left lateral medulla. This section contains the largest transverse diameter of the lateral medullary infarction. The softening focus has the shape of an irregular ellipse with the largest axis in the ventrolateral-dorsomedial direction. Among the involved areas mentioned by Wallenberg were the lateral half of the left dorsal accessory olivary nucleus; lateral reticular nucleus (nucleus lateralis medullae); cells of the reticular formation (formatio reticularis grisea); the nucleus ambiguus; internal arcuate fibers (fibrae arcuatae internae) from the nucleus cuneatus (Burdach nucleus); the ventral two-thirds of the spinal trigeminal tract and nucleus; vagus nerve fibers passing through the spinal trigeminal tract and nucleus; dorsal spinocerebellar fibers to the restiform body (corpus restiforme; inferior cerebellar peduncle); anterior spinocerebellar tract (ventral spinocerebellar tract; tractus spinocerebellaris ventralis; Gowers’ bundle); spinotectal fibers (spinomesencephalic fibers; fibrae spinotectales) and spinothalamic tract (spinothalamicae, tract of Edinger); rubrospinal tract (Monakow’s bundle); fibers descending from Deiters’ nucleus to the anterior column of the spinal cord; and anterior external arcuate fibers (ventral external arcuate fibers; fibrae arcuatae externae ventrales) from the right dorsal column nuclei (especially Goll’s) to the left restiform body (corpus restiforme; inferior cerebellar peduncle). (Source: Wallenberg A. Anatomischer Befund in einem als “acute Bulbär-aVection [Embolie der Art. cerebellar. post. inf. sinistr?]” bescreidenen Falle. Archiv für Psychiatrie und Nervenkrankheiten 1901;34:923-59. Edited by Dr. Douglas J Lanska.)