title: Laron syndrome abnormalities: spinal stenosis, os odontoideum, degenerative changes of the atlanto-odontoid joint, and small oropharynx.
abstract: OBJECTIVE
  Patients with Laron syndrome have an inborn growth hormone resistance. We investigated abnormalities in the upper airways and cervical spine in patients with Laron syndrome.
  
  
  METHODS
  We prospectively examined 11 patients (one child aged 9 years and 10 adults aged 36-68 years), 10 of whom underwent MR imaging of the spine or head; nine, radiography of the cervical spine; and four, CT of C1-C2. The width of the spinal canal was evaluated visually and quantitatively and compared with reference values. The smallest diameter of the oropharynx and the thickness of the palate were measured and compared with reference values. Nine age-matched female patients referred for MR imaging for unrelated reasons served as control subjects.
  
  
  RESULTS
  Cervical spinal stenosis was present in seven of the adult patients, within a confidence interval of 95%. Anomaly of the dens compatible with os odontoideum was present in three patients, causing focal myelomalacia in two. The atlanto-odontoid joint showed osteoarthritic changes in six of the adult patients. The mediolateral diameter of the oropharynx was significantly smaller in the patients with Laron syndrome than in the control subjects (P <.005). There was no difference in the thickness of the soft palate.
  
  
  CONCLUSIONS
  Patients with Laron syndrome develop significant narrowing of the cervical spinal canal and early degenerative changes of the atlanto-odontoid joint. Laron syndrome is associated with os odontoideum causing myelomalacia. The dimensions of the oropharynx are small. Patients may be prone to neurologic morbidity and sleep disturbances. Routine MR imaging of the cervical spine is recommended in these patients.
authors.affiliation: Department of Imaging, Schneider Children's Medical Center of Israel, Petah Tiqva.
authors.forename: Liora
authors.initials: L
authors.lastname: Kornreich
authors.forename: Gadi
authors.initials: G
authors.lastname: Horev
authors.forename: Michael
authors.initials: M
authors.lastname: Schwarz
authors.forename: Boaz
authors.initials: B
authors.lastname: Karmazyn
authors.forename: Zvi
authors.initials: Z
authors.lastname: Laron
mesh_terms: D000328:Adult; D000368:Aged; D001268:Atlanto-Axial Joint / Q000000981:diagnostic imaging / Q000473:pathology; D002574:Cervical Vertebrae / Q000000981:diagnostic imaging / Q000473:pathology; D002648:Child; D004392:Dwarfism / Q000473:pathology*; D005260:Female; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000172:deficiency; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009809:Odontoid Process; D009960:Oropharynx / Q000002:abnormalities*; D010003:Osteoarthritis / Q000150:complications / Q000175:diagnosis; D011446:Prospective Studies; D013115:Spinal Canal / Q000473:pathology; D013130:Spinal Stenosis / Q000150:complications / Q000175:diagnosis* / Q000000981:diagnostic imaging; D014057:Tomography, X-Ray Computed
chemical_list: D007334:Insulin-Like Growth Factor I