Magnetic resonance imaging of extraocular rectus muscles abnormalities in acute acquired concomitant esotropia

AIM:To investigate the difference of medial rectus(MR)and lateral rectus(LR)between acute acquired concomitant esotropia(AACE)and the healthy controls(HCs)detected by magnetic resonance imaging(MRI).METHODS:A case-control study.Eighteen subjects with AACE and eighteen HCs were enrolled.MRI scanning data were conducted in target-controlled central gaze with a 3-Tesla magnetic resonance scanner.Extraocular muscles(EOMs)were scanned in contiguous image planes 2-mm thick spanning the EOM origins to the globe equator.To form posterior partial volumes(PPVs),the LR and MR cross-sections in the image planes 8,10,12,and 14 mm posterior to the globe were summed and multiplied by the 2-mm slice thickness.The data were classified according to the right eye,left eye,dominant eye,and non-dominant eye,and the differences in mean cross-sectional area,maximum cross-sectional area,and PPVs of the MR and LR muscle in the AACE group and HCs group were compared under the above classifications respectively.RESULTS:There were no significant differences between the two groups of demographic characteristics.The mean cross-sectional area of the LR muscle was significantly greater in the AACE group than that in the HCs group in the non-dominant eyes(P=0.028).The maximum cross-sectional area of the LR muscle both in the dominant and non-dominant eye of the AACE group was significantly greater than the HCs group(P=0.009,P=0.016).For the dominant eye,the PPVs of the LR muscle were significantly greater in the AACE than that in the HCs group(P=0.013),but not in the MR muscle(P=0.698).CONCLUSION:The size and volume of muscles dominant eyes of AACE subjects change significantly to overcome binocular diplopia.The LR muscle become larger to compensate for the enhanced convergence in the AACE.

Acute acquired concomitant esotropia with congenital paralytic strabismus:A case report

BACKGROUND An unusual case of acute acquired concomitant esotropia(AACE)with congenital paralytic strabismus in the right eye is reported.CASE SUMMARY A 23-year-old woman presented with complaints of binocular diplopia and esotropia of the right eye lasting 4 years and head tilt to the left since 1 year after birth.The Bielschowsky head tilt test showed right hypertropia on a right head tilt.She did not report any other intracranial pathology.A diagnosis of AACE and right congenital paralytic strabismus was made.Then,she underwent medial rectus muscle recession and lateral rectus muscle resection combined with inferior oblique muscle myectomy in the right eye.One day after surgery,the patient reported that she had no diplopia at either distance or near fixation and was found to be orthophoric in the primary position;furthermore,her head posture immediately and markedly improved.CONCLUSION In future clinical work,in cases of AACE combined with other types of strabismus,we can perform conventional single surgery for both at the same time,and the two types of strabismus can be solved simultaneously.