Ultrastructural study of the superior tarsal Müller muscle in ptosis patients undergoing müllerectomy

Objective Is using transmission electron microscopy to examine the ultrastructure of Müller’s muscle (MM) specimens obtained from Müllerectomy surgery in selected patients with ptosis of various etiologies. Patients and methods During Müllerectomy surgery, MM were resected using the open-sky technique from the conjunctival side. Specimens were then prepared for electron microscopy examination. The resulting electron micrograph images were captured and analyzed. The comparison of the ultrastructural changes in MM in all patients is displayed. Results Most changes in MM are shared among patients with ptosis of various etiologies. The abnormalities in muscle ultrastructure are most pronounced in the neurogenic and the congenital cases. MM in acquired aponeurotic ptosis was more affected in older patients than in younger ones. Conclusion In all studied cases of ptosis, regardless of the cause, there is variable involvement of the ultrastructure of MM. However, the most significant changes in MM ultrastructure were seen in the neurogenic and congenital cases.