title: Adult with Middle Interhemispheric Variant of Holoprosencephaly: Neuropsychological, Clinical, and Radiological Findings.
abstract: OBJECTIVE
  The middle interhemispheric variant of holoprosencephaly (MIHV) is a mild, rare variant of holoprosencephaly. Only a few cases of children with MIHV have been reported. Here we report in detail an adult case.
  
  
  METHODS
  The patient is a female in her 30s. The patient underwent an extensive neuropsychological examination, a neurological examination and a magnetic resonance imaging.
  
  
  RESULTS
  Neuroradiologically, the patient had a typical finding of MIHV, with the absence of the central corpus callosum and union of posterior frontal and anterior parietal gyri. In neuropsychological examination, the patient had average or above average performance in verbal comprehension, naming, reading and writing, and below average performance in perceptual reasoning, visuospatial abilities, processing speed and memory. Also difficulties in mathematical abilities, psychomotor skills, and executive functions were found. No gross neurological involvement was noted. She was diagnosed with atypical depression, post-traumatic stress disorder and a dissociative disorder in early adulthood. Despite cognitive deficits, she was able to achieve a tertiary level education.
  
  
  CONCLUSIONS
  This is the first adult case of MIHV described in detail. Our case emphasizes the possibility of a missed diagnosis of marked brain malformations in patients with craniofacial abnormalities. More cases and prospective follow-up studies are needed to understand the evolvement of both neuropsychological and psychiatric symptoms in these patients.
authors.affiliation: Division of Cognitive and Neuropsychology, Institute of Behavioural Sciences, University of Helsinki, Helsinki, Finland maarit.virta@helsinki.fi.
authors.forename: Maarit
authors.initials: M
authors.lastname: Virta
authors.affiliation: Division of Cognitive and Neuropsychology, Institute of Behavioural Sciences, University of Helsinki, Helsinki, Finland.
authors.forename: Jyrki
authors.initials: J
authors.lastname: Launes
authors.affiliation: Helsinki Medical Imaging Center, University of Helsinki, Helsinki, Finland.
authors.forename: Leena
authors.initials: L
authors.lastname: Valanne
authors.affiliation: Division of Cognitive and Neuropsychology, Institute of Behavioural Sciences, University of Helsinki, Helsinki, Finland.
authors.forename: Laura
authors.initials: L
authors.lastname: Hokkanen
mesh_terms: D000328:Adult; D003072:Cognition Disorders / Q000175:diagnosis* / Q000209:etiology*; D003337:Corpus Callosum / Q000000981:diagnostic imaging*; D003863:Depression / Q000175:diagnosis / Q000209:etiology; D005260:Female; D016142:Holoprosencephaly / Q000150:complications*; D006801:Humans; D008279:Magnetic Resonance Imaging; D001523:Mental Disorders / Q000175:diagnosis; D009460:Neurologic Examination; D009483:Neuropsychological Tests
keywords: Cognition; Holoprosencephaly; MIHV; Neuropsychology; Syntelencephaly