title: The Medial and Lateral Lemnisci: Anatomically Adjoined But Functionally Distinct Fiber Tracts.
abstract: OBJECTIVE
  The dense and complex distribution of neural structures in the brainstem makes it challenging to understand their real configuration. We used the fiber microdissection technique to show the course of the medial and lateral lemnisci within the brainstem. Although these structures seem anatomically alike, they are functionally distinct.
  
  
  METHODS
  Fifteen human brainstems and 8 brain hemispheres (formalin-fixed and previously frozen) were dissected and studied under the operating microscope by applying the fiber microdissection technique.
  
  
  RESULTS
  We delineated and described the medial and lateral lemnisci, noting their gross elaborate arrangement. These structures are intimately compact and closely related to one another in their common trajectory through the tegmenta of the pons and midbrain. However, we were not able to identify the exact origin and termination of their fibers or the accurate delimitation between the medial lemniscus, spinothalamic tract, and lateral lemniscus along their course in the brainstem.
  
  
  CONCLUSIONS
  Using the fiber microdissection technique, we were able to define a general perspective of the topography and architecture of the medial and lateral lemnisci in the brainstem. This perspective should be incorporated into interpretations of magnetic resonance imaging techniques, recognizing both their benefits and limitations. It should also be applied to surgical planning and strategies to achieve a safer and more precise microsurgical procedure.
authors.affiliation: Department of Neurosurgery, Yeditepe University School of Medicine, Kozyatagi Kadikoy, Istanbul, Turkey.
authors.forename: Ruben
authors.initials: R
authors.lastname: Rodríguez-Mena
authors.affiliation: Department of Neurosurgery, Yeditepe University School of Medicine, Kozyatagi Kadikoy, Istanbul, Turkey. Electronic address: drture@yahoo.com.
authors.forename: Uğur
authors.initials: U
authors.lastname: Türe
mesh_terms: D001933:Brain Stem / Q000033:anatomy & histology* / Q000000981:diagnostic imaging* / Q000601:surgery; D002102:Cadaver; D006801:Humans; D042282:Microdissection; D066127:White Matter / Q000033:anatomy & histology* / Q000000981:diagnostic imaging* / Q000601:surgery
keywords: Brainstem; Fiber microdissection technique; Lateral lemniscus; Medial lemniscus; White matter anatomy