Towards understanding ocular motility: III, IV and VI.
The study of the ocular-motor nerves must be exhaustive from their source (nuclei in the brainstem) down to the effector muscles (orbit). Visual disturbances have to be analysed by differentiating between a decrease in visual acuity and ocular-motor disorders. Imaging tests are dominated by MRI, including fine slices and gadolinium injection. A study of the Circle of Willis vessels is often useful, and essential in the case of type III impairment. A further CT scan is essential for analysis of the foramina, base of the skull and orbital walls. Impairment of CN VI requires a CT scan of the apex of petrous. The study of the cavernous sinuses must be in-depth (T2 and T1 after gadolinium and elimination of fats) and always comparative. Impairment of CN III is often complex, difficult to identify precisely (complete or partial, with or without a pupil impairment, associated with other neurological signs) and requires a reasoned study based on anatomical, semiological and pathological knowledge. Other than tumour diseases, it is necessary to consider less well known malformative, ischemic and inflammatory aetiology.
Medical Imaging Department, Adolphe de Rothschild Foundation, 25, rue Manin, 75019 Paris, France. Electronic address: patriciakoskas@free.fr.
P
P
Koskas
F
F
Héran
D000010:Abducens Nerve / Q000473:pathology; D020434:Abducens Nerve Diseases / Q000175:diagnosis* / Q000473:pathology; D002941:Circle of Willis / Q000473:pathology; D003287:Contrast Media; D004172:Diplopia / Q000209:etiology; D005682:Gadolinium; D006801:Humans; D007089:Image Enhancement; D007090:Image Interpretation, Computer-Assisted; D008279:Magnetic Resonance Imaging; D009460:Neurologic Examination; D015835:Ocular Motility Disorders / Q000175:diagnosis*; D009802:Oculomotor Nerve / Q000473:pathology; D015840:Oculomotor Nerve Diseases / Q000175:diagnosis* / Q000473:pathology; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed; D014321:Trochlear Nerve / Q000473:pathology; D020432:Trochlear Nerve Diseases / Q000175:diagnosis* / Q000473:pathology; D014786:Vision Disorders / Q000209:etiology
D003287:Contrast Media; D005682:Gadolinium
Anatomy; CBH; Claude Bernard-Horner; Cranial nerves; Diplopia; ICH; INO; Internuclear ophthalmoplegia; Intracranial hypertension; MLB; MRI; Median longitudinal bundle