Novel Inferior Oblique Muscle Y Splitting Procedure to Minimize the Anti-Elevation Syndrome: A Pilot Study

Abstract

Amar Pujari, Sujeeth Modaboyina, Rajeswari Thangavel, Monika Yadav, Swati Phuljhele, Rohit Saxena Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, IndiaCorrespondence: Amar Pujari, Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, Room No. 212, RPC-1, AIIMS, New Delhi, India, Email [email protected]: To describe novel Y splitting procedure of inferior oblique muscle to mitigate the anti-elevation syndrome.Methods: A pilot, prospective interventional study was undertaken to assess the effect of inferior oblique muscle Y-splitting in patients with unilateral 3+ or more overaction. To correct primary gaze hypertropia and the excyclotorsion, a Y-splitting procedure was performed (along with routine horizontal muscle surgery as per the deviation) in 14 subjects. The effect of surgery was assessed at baseline and at 6 months post-intervention.Results: The mean age of 14 subjects was 25.14± 7.70 years. The mean pre-operative hypertropia, excyclotorsion and inferior oblique muscle over-action was 18.42± 3.50 PD, 14.14± 2.65 degrees, and +3.21± 0.42 respectively. Following surgery, this was reduced to 1.57± 1.74 PD of residual hypertropia (a net correction of 16.85± 2.31 PD, p = 0.005), 3.85± 1.46 degrees of residual excyclotorsion (a net correction of 10.28± 1.72 degrees, p < 0.05), and +0.28± 0.46 of residual inferior oblique over-action (a net correction ∼+3) at the end of 6 months. Amongst fourteen patients, three patients still experienced residual/variable anti-elevation effect, and during the study period none of them experienced any adverse event and none of them required any additional surgeries.Conclusion: While anteriorizing the inferior oblique muscle to correct primary gaze hypertropia and the excyclotorsion, a novel “Y splitting” procedure can be followed to achieve the desired results with mitigated anti-elevation effect.Keywords: inferior oblique muscle surgery, anti-elevation syndrome, Y-splitting of the inferior oblique

Keywords

• inferior oblique muscle surgery
• anti-elevation syndrome
• y-splitting of the inferior oblique.