摘要
Background: Recent reports postulate that the concomitant vertical deviation f ound in congenital superior oblique palsy is due to mechanical abnormalities rat her than a congenitally paretic muscle, and is overcome in most patients by fusi on. On the basis of the clinical characteristics alone a primary paresis is inde ed unlikely. Although intraoperatively a different elasticity of the superior ob lique tendon exists in congenital versus acquired cases of superior oblique pals y, preoperatively performed MR imaging shows that the clinical findings in conge nital superior oblique muscle malfunction could nevertheless be of paretic origi n. Materials andMethods: Seventeen consecutive patients (males: n=13; females: n =4) were examined. The vertical deviation in adduction was concomitant in vertic al versions, the excyclotropia was small and concomitant in all directions of ga ze and was less than 10°even after diagnostic occlusion. All patients showed a positive Bielschowsky head tilt phenomenon and large fusional ability. We perfor med preoperative MR imaging of both orbits in high resolution 3 mm sections in c oronal and axial orientationswith and without contrast enhancement. Results: In sixteen patients we found a significant reduction in muscle volume or even total aplasia of the superior oblique muscle of the affected side in comparison to th e sound muscle on the other side. In contrast, two patients had a full blown cli nical picture of a congenital superior oblique palsy but showed symmetrical musc le volumes on both sides in all coronal sections. Conclusions: Hypoplasia or apl asia of the superior oblique muscle on magnetic resonance imaging provides evide nce for a primary paretic cause for the vertical squint found with congenital su perior oblique dysfunction. It is not clear, however, whether this is caused by a primary hypoplasia or is of neurogenic origin. Our data together with the cons istent difference in tendon morphology of the congenital and acquired forms of s uperior oblique palsy seem to exclude a purely neurogenic cause for the affectio n.
Background: Recent reports postulate that the concomitant vertical deviation f ound in congenital superior oblique palsy is due to mechanical abnormalities rat her than a congenitally paretic muscle, and is overcome in most patients by fusi on. On the basis of the clinical characteristics alone a primary paresis is inde ed unlikely. Although intraoperatively a different elasticity of the superior ob lique tendon exists in congenital versus acquired cases of superior oblique pals y, preoperatively performed MR imaging shows that the clinical findings in conge nital superior oblique muscle malfunction could nevertheless be of paretic origi n. Materials andMethods: Seventeen consecutive patients (males: n=13; females: n =4) were examined. The vertical deviation in adduction was concomitant in vertic al versions, the excyclotropia was small and concomitant in all directions of ga ze and was less than 10°even after diagnostic occlusion. All patients showed a positive Bielschowsky head tilt phenomenon and large fusional ability. We perfor med preoperative MR imaging of both orbits in high resolution 3 mm sections in c oronal and axial orientationswith and without contrast enhancement. Results: In sixteen patients we found a significant reduction in muscle volume or even total aplasia of the superior oblique muscle of the affected side in comparison to th e sound muscle on the other side. In contrast, two patients had a full blown cli nical picture of a congenital superior oblique palsy but showed symmetrical musc le volumes on both sides in all coronal sections. Conclusions: Hypoplasia or apl asia of the superior oblique muscle on magnetic resonance imaging provides evide nce for a primary paretic cause for the vertical squint found with congenital su perior oblique dysfunction. It is not clear, however, whether this is caused by a primary hypoplasia or is of neurogenic origin. Our data together with the cons istent difference in tendon morphology of the congenital and acquired forms of s uperior oblique palsy seem to exclude a purely neurogenic cause for the affectio n.
出处
《世界核心医学期刊文摘(眼科学分册)》
2005年第10期56-56,共1页
Digest of the World Core Medical Journals:Ophthalmology