Surgical outcomes in patients with congenital superior oblique palsy: A comparison between clinical and radiological diagnosis

Purpose

The diagnosis of superior oblique (SO) palsy can be achieved by examining the radiological and clinical characteristics. Despite their usefulness, the radiological and clinical methods are not always aligned to each other. The objective of this research is to analyze the surgical results of eyes with SO palsy, based on whether the diagnosis was made radiologically or clinically.

Design

A prospective study, conducted at a single tertiary hospital.

Methods

Following the diagnosis of SO palsy, either through clinical assessment or radiological imaging, the patients were categorized into three distinct groups according to their clinical measurements and MRI findings. Group 1 exhibited consistent clinical measurements and MRI findings indicating SO palsy, whereas Group 2 displayed clinical measurements without MRI confirmation. In contrast, Group 3 presented inconclusive measurements, but MRI scans revealed signs of atrophy. Patients underwent inferior oblique (IO) myectomy with and without contralateral inferior rectus recession and ocular deviation before and after myectomy were collected.

Results

The study included 49 patients with congenital unilateral SO palsy (average age: 30 years). Out of 35 patients who tested positive across all three stages of the test, 15 did not show notable muscle atrophy in their MRI findings. In contrast, among those who displayed muscle atrophy in their MRI scans, 58.8 % had positive outcomes in all steps of the three-step assessment. Group 1 and 3 displayed a reduced muscle volume measuring 110.988 ± 42.49 mm³ and 91.5 ± 56.8 mm³, respectively, on the affected side. Group 2 showcased a muscle volume of 184.1 ± 44.64 mm³ on the affected side. In all three groups with SO palsy eyes who underwent IO myectomy, there was a reduction in hypertropia in the primary position, with no statistically significant differences observed among the groups (P = 0.1). All five patients with SO palsy who underwent IO myectomy with contralateral inferior rectus recession were classified in group 3, and they exhibited a significant reduction in hypertropia postoperatively.

Conclusion

Comparable results can be attained through IO surgery in patients with SO palsy, regardless of whether they are diagnosed through clinical or radiological means.