title: Clinical correlation of imaging findings in congenital cranial dysinnervation disorders involving abducens nerve.
abstract: OBJECTIVE
  High-resolution magnetic resonance imaging (MRI) of intracranial parts of sixth nerve and seventh nerve and the extraocular muscles (EOMs) in orbit to correlate the clinical characteristics in patients with two special forms of strabismus in congenital cranial dysinnervation disorders which are Duane's retraction syndrome (DRS) and Mobius syndrome.
  
  
  METHODS
  Morphological analysis by 3T MRI of orbit (using surface coils) and brain (using 32 channel head coil) was performed on 6 patients with clinical DRS (1 bilateral), 2 cases with Mobius syndrome, and 1 case with congenital sixth nerve palsy. These were compared with findings in five controls.
  
  
  RESULTS
  We observed absence/hypoplasia of sixth nerve in five out of seven eyes with DRS (71.42%), anomalous course in one eye, sixth and seventh nerve absence/hypoplasia in affected eyes with Mobius syndrome and bilateral absence/hypoplasia of the sixth nerve in congenital sixth nerve palsy. For EOMs we calculated maximum diameter, area, and circumference of muscles using Osirix software, and noticed significant hypoplasia of lateral rectus in comparison to controls (P < 0.001).
  
  
  CONCLUSIONS
  MRI gives useful information regarding confirmation of clinical diagnosis and its neurological anomalies in complex cases and helps to plan tailor made surgical management.
authors.affiliation: Department of Ophthalmology, Dr. Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: Chanchal
authors.initials: C
authors.lastname: Gupta
authors.affiliation: Department of Ophthalmology, Dr. Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: Pradeep
authors.initials: P
authors.lastname: Sharma
authors.affiliation: Department of Ophthalmology, Dr. Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: Rohit
authors.initials: R
authors.lastname: Saxena
authors.affiliation: Department of Neuroradiology, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: Ajay
authors.initials: A
authors.lastname: Garg
authors.affiliation: Department of Radiodiagnosis, Dr. Rajendra Prasad Centre for Ophthalmic Sciences, New Delhi,, India.
authors.forename: Sanjay
authors.initials: S
authors.lastname: Sharma
mesh_terms: D000010:Abducens Nerve / Q000000981:diagnostic imaging; D020434:Abducens Nerve Diseases / Q000151:congenital / Q000175:diagnosis*; D000015:Abnormalities, Multiple; D004370:Duane Retraction Syndrome / Q000175:diagnosis*; D006801:Humans; D021621:Imaging, Three-Dimensional; D008279:Magnetic Resonance Imaging / Q000379:methods*; D020331:Mobius Syndrome / Q000175:diagnosis*; D009801:Oculomotor Muscles / Q000000981:diagnostic imaging / Q000294:innervation*; D009915:Orbit / Q000000981:diagnostic imaging*; D010865:Pilot Projects