title: Central Trochlear Palsy: Report of Two Patients With Ipsilesional Palsy and Review of the Literature.
abstract: The trochlear (fourth) nerve is the only cranial nerve that decussates before emerging from the posterior aspect of the brainstem. Lesions involving the trochlear nucleus or fascicles mostly give rise to contralesional superior oblique palsy (SOP).
  
  
  
  We report 2 patients with SOP on the side of intraaxial lesions with a literature review on central trochlear palsy.
  
  
  
  The lesions are more commonly located posterior to the cerebral aqueduct in patients with ipsilesional SOP than in those with contralesional SOP.
  
  
  
  Intraaxial lesions may cause ipsilesional or contralesional SOP depending on the lesion location along the course of trochlear fascicle in the brainstem.
authors.affiliation: Department of Neurology (S-HJ), Chungnam National University Hospital, Daejeon, Korea; Department of Neurology (S-HK, S-HP, J-SK), Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam, Korea; Department of Neurology (S-HL), Chonnam National University Medical School, Gwangju, Korea; and Department of Biomedical Laboratory Science (H-JK), Kyungdong University, Goseong-gun, South Korea.
authors.forename: Seong-Hae
authors.initials: SH
authors.lastname: Jeong
authors.forename: Sung-Hee
authors.initials: SH
authors.lastname: Kim
authors.forename: Seung-Han
authors.initials: SH
authors.lastname: Lee
authors.forename: Seong-Ho
authors.initials: SH
authors.lastname: Park
authors.forename: Hyo-Jung
authors.initials: HJ
authors.lastname: Kim
authors.forename: Ji-Soo
authors.initials: JS
authors.lastname: Kim
mesh_terms: D000369:Aged, 80 and over; D005133:Eye Movements / Q000502:physiology*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D009801:Oculomotor Muscles / Q000000981:diagnostic imaging / Q000503:physiopathology*; D014321:Trochlear Nerve / Q000473:pathology*; D020432:Trochlear Nerve Diseases / Q000175:diagnosis* / Q000503:physiopathology