Photo Credit: robertprzybysz
The following is a summary of “Surgical Management of Masquerading Superior Oblique Palsy,” published in the February 2025 issue of American Journal of Ophthalmology by Meng et al.
Researchers conducted a retrospective study comparing surgical outcomes between superior oblique (SO) palsy (SOP) and masquerading SO palsy (mSOP).
They reviewed medical records of individuals with SOP and mSOP from 1991 to 2024. The SOP cases had a maximum SO cross-section in the hypertropic eye of no more than 80% of that in the fellow eye, while mSOP cases had bilaterally symmetrical SO muscles on magnetic resonance imaging. Surgical procedures and the effects on hypertropia (HT) were compared between groups.
The results showed that 39 individuals with SOP had a mean age of 38±20 years, while 18 with mSOP had a mean age of 36±17 years. The maximum palsied SO cross-section measured 10.6±3.8mm2, significantly smaller than 18.9±4.0mm2 in the contralateral eye (P <0.0001), whereas mSOP cases had bilaterally symmetrical SO muscles. Mean preoperative central gaze HT was similar between SOP (14.7±9.8Δ) and mSOP (11.0±6.9Δ) (P=0.2). The most common procedure was ipsilateral inferior oblique (IO) weakening with contralateral inferior rectus (IR) recession, followed by IO weakening alone and IR recession alone. After a follow-up of 41±65 months for SOP and 22±41 months for mSOP, central gaze HT improved from 14.7±9.8Δ to 1.7±4.1Δ in SOP and from 11.0±6.9Δ to -2.9±5.4Δ in mSOP (both P <0.0001). The surgical effect was comparable, with HT reductions of 13.2±10.3Δ in SOP and 14.1±10.0Δ in mSOP. Re-operation rates remained low and similar across both groups.
Investigators concluded that mSOP and SOP yielded similar clinical characteristics and surgical effects, suggesting that factors other than SO muscle function influence head-tilt dependent cyclovertical strabismus.
Source: ajo.com/article/S0002-9394(25)00075-3/abstract
