title: Early Dorsal Midbrain Syndrome Mimicking an Adie's Tonic Pupil.
abstract: BACKGROUND
  While tonic pupils have been attributed to various diseases, including syphilis, herpes zoster, orbital trauma, temporal arteritis, endometriosis, and paraneoplastic syndromes, obstructive hydrocephalus has not been implicated.
  
  
  METHODS
  A 36-year-old woman visited a neurology department with a 7-day history of throbbing headache and blurred vision in both eyes. She had early dorsal midbrain syndrome mimicking an Adie's tonic pupil, and cholinergic supersensitivity was demonstrated using topical 0.125% pilocarpine. Brain MRI revealed obstructive hydrocephalus at the level of the aqueduct of Sylvius, and her symptoms resolved 4 days after surgery.
  
  
  CONCLUSIONS
  We report a patient with early dorsal midbrain syndrome that was initially believed to represent a tonic pupil on the basis of pharmacologic testing. The findings in our patient suggested that early dorsal midbrain syndrome mimicking an Adie's tonic pupil can be caused by obstructive hydrocephalus compressing the Edinger-Westphal nucleus.
authors.affiliation: Department of Neurology, Sanggye Paik Hospital, Inje University College of Medicine, Seoul, Korea.
authors.forename: Sang Won
authors.initials: SW
authors.lastname: Han
authors.forename: Jung Ho
authors.initials: JH
authors.lastname: Ryu
authors.forename: Jong Sam
authors.initials: JS
authors.lastname: Baik
authors.forename: Jeong Yeon
authors.initials: JY
authors.lastname: Kim
authors.forename: Yong Soon
authors.initials: YS
authors.lastname: Hwang
authors.forename: Jae Hyeon
authors.initials: JH
authors.lastname: Park
references.citation: Ophthalmologica. 2004 Mar-Apr;218(2):141-3
references.pmid: 15004505
references.citation: J Pediatr Ophthalmol Strabismus. 2005 May-Jun;42(3):176-9
references.pmid: 15977871
references.citation: Rev Neurol (Paris). 2005 Oct;161(10):963-6
references.pmid: 16365626
references.citation: Br J Ophthalmol. 1984 Feb;68(2):135-8
references.pmid: 6691957