[Oculomotor disorders and enlargement of the extraocular muscles]

Aetiologic conditions for enlargement of extra ocular muscles are graves' orbitopathy, acute or subacute myositis as a subgroup of inflammatory orbital pseudotumor, and sometimes lymphoid or metastatic tumor. The distinction of these aetiologies can be made on clinical versus CT Scan or IRM grounds with two different patterns of oculomotor disfunction. Restrictive extensibility, which found expression in the antagonist field, is typical of grave's myopathy, sequelae of subacute myositis or acute myositis of the superior oblique. Deficiency of the enlarged muscle's contractibility is typical of a recent and transient myositis involving a rectus muscle or of a rare tumor of an extraocular muscle.