[The effect of superior oblique tucking on the Bielschowsky head tilt test]

To investigate the effect of superior oblique tucking on the Bielschowsky head tilt test.

A retrospective analysis of 22 patients with congenital unilateral superior oblique palsy, who underwent tucking of the superior oblique tendon in Tianjin Eye Hospital, depending on vertical deviation in the primary position, ocular motility, objective cyclotorsion and abnormal head posture. Bielschowsky head tilt test was evaluated quantitatively by the prism cover test. Α positive Bielschowsky head tilt test was defined as one in which the vertical deviation when the head tilt to the side of the paresis was at least 5. 0(△) greater than that on tilt to the uninvolved side. The follow-up period ranged from 3 to 12 months (mean 4.6 months). Kolmogorov-Smirnov (K-S), Rank sum test and Spearman correlation analysis statistical methods were used in this study.

All patients had vertical deviation and significant abnormal head posture before operation. After the procedure of superior oblique tucking,vertical deviation and symptom of unacceptable abnormal head posture were ameliorated or disappeared. OBJECTIVE torsion was 15.62°±7.36° before the surgery, 9.91°±10.09°1d after the surgery and 11.25°±9.17°at the last follow-up visit, respectively (P<0.05). We found that there were positive correlations between the objective cyclotorsion and the vertical deviation difference value between the paralyzed side and uninvolved side at 1 d after the surgery and last follow-up visit(P<0.05). The vertical deviation of the paresised eye when the head tilted to the side of paresis side and uninvolved side difference were 5.00(△)-17.00(△), average 8.68(△)±3.23(△), 1.00(△)-8.00(△),average 3.36(△)±2.01(△) and 0.00(△)-14.00(△),average 3.77(△)±3.01(△), preoperatively, 1d after the surgery and at the last follow-up visit respectively. Using Rank sum test, the pre-and postoperative difference was statistically significant (Z=-4.64, P<0.01). A positive Bielschowsky head tilt test was found in all cases preoperatively. The results of Bielschowsky tilt test was still positive in 5 cases and negative in 17 cases (77.3%).

In most cases with unilateral superior oblique paresis, the results of Bielschowsky tilt test became negative after superior oblique tucking. The long-standing results is worthy of observation. (Chin J Ophthalmol, 2016, 52: 589-595).