Lower eyelid position after ptosis repair in patients with blepharoptosis

To determine the changes in the lower eyelid position, following ptosis surgery of the upper eyelid of the same eye in blepharoptosis patients.

Upper eyelid ptosis can indeed impact the lower eyelid position in both congenital and acquired subgroups, leading to a dynamic scleral show.This concern is often addressed during preoperative counseling for blepharoptosis repair.[14][15] There is a belief that weakening the levator muscle may result in an additional contraction of the levator muscle, accompanied by traction of the superior rectus muscle, causing an upward rotation of the globe.This, in turn, leads to an additional contraction of the inferior rectus muscle to maintain the horizontal visual axis, which also pulls on the inferior suspensory ligament of Lockwood. 137][18] Upper eyelid ptosis has a notable impact on the lower eyelid site, resulting in the lower scleral show.In this study, we assessed the changes in the lower eyelid position following ptosis surgery of the upper eyelid of the same eye.REC.1399.876)that had been defined in full accordance with the declaration of Helsinki.Written consent was obtained from all participants in the study before enrolling in the study.Inclusion criteria were as follows, patients age more than 5 years of age with a diagnosis of congenital or acquired blepharoptosis.Patients with a history of eyelid surgery, extraocular myopathies such as myasthenia gravis, oculopharyngeal dystrophy, myotonic dystrophy, chronic progressive external ophthalmoplegia (CPEO), third nerve palsy or strabismus surgery were excluded from the study.Also, the cases with a lack of marginal reflex distance one (MRD-1) increase after surgery were excluded.

| Surgical technique
The surgical procedure was based on the small-incision levator resection for the correction of congenital ptosis that the first author (BE) has introduced previously. 19The procedure began by marking the desired upper eyelid crease with a length of 10-12 mm.A skin incision was made, and dissection was carried out underneath the orbicularis oculi muscle to expose the upper surface of the tarsal plate.Two partial thickness 5-0 mersilene sutures were placed on the tarsus at a specific location on the plate.Next, further dissection allowed access to the levator aponeurosis beneath the preaponeurotic fat pad after opening the orbital septum.Suturing was done on the levator muscle, and the amount of resection was adjusted based on MRD-1 to achieve the desired eyelid height while considering the patient's position during the procedure.A section of redundant levator muscle was removed, and bleeding was controlled with bipolar cautery.The skin incision was then closed using three separate 6-0 prolene sutures, ensuring an aesthetically pleasing eyelid crease. 19

| Outcome assessment
MRD-1 and MRD two (MRD-2) were measured before and the 6 to months after the surgery and LF was measured before surgery.To measure the LF, we measure the distance between the eyelids with a ruler while the patient sits and looks at the lowest and highest point.
LF was assessed by measuring upper eyelid excursion from extreme down to upgaze while pressing over the patient's eyebrow to cancel the action of the frontalis muscle. 20,21D-1 and MRD-2 were defined as the distance between the upper and lower eyelid margins to the corneal reflex when the patient is fixating on the light source, respectively.p < 0.05 was considered statistically significant.1).
Both the congenital and acquired groups showed a decrease in MRD-1 after treatment (p < 0.001 for both groups) (Table 2).

| DISCUSS ION
The present study demonstrated a significant postoperative reduction of MRD-2, which is consistent with previous research.Matsuo ptosis surgery and found that 56.8% of myogenic and 80% of aponeurotic cases exhibited local changes in the lower eyelid before surgery, which improved in 75% of aponeurotic and 57% of myogenic cases in the postoperative phase.The asymmetry of the lower eyelid was significantly improved as well.They also reported a significant increase in MRD-1 and a notable improvement in MRD-2 both before and after the surgical procedure. 17Additionally, they found that the severity of preoperative ptosis was significantly associated with a higher degree of scleral show (MRD-2) in this group, which is consistent with our study findings. 15,17rgical intervention is one of the approaches used to correct the position of the lower eyelid, which can be accompanied by complications such as scarring, lagophthalmos, undercorrection, and overcorrection. 19,22Noninterference with the lower eyelid and focusing on F I G U R E 1 Comparing preoperative versus postoperative MRD-1 and MRD-2.
This prospective interventional before and after the study was performed on a patient with congenital and acquired blepharoptosis who underwent surgery at a university-based hospital (Feiz Hospital, Isfahan, Iran) and private clinic from September 2019 to 2021.The institutional review board of Isfahan University of Medical Sciences approved the trial protocol (IR.MUI.MED.
et al. conducted a study with 100 consecutive patients presenting various degrees and stages of aponeurotic blepharoptosis to investigate whether dynamic lower scleral show is caused by aponeurosis disinsertion from the tarsus and whether it can be surgically corrected through aponeurotic advancement.Their findings revealed that the postoperative area enclosed by the lower lid margin was significantly lower than the preoperative measurement. 12Similar to the present study, Bahmani et al. conducted a clinical study to evaluate the change in lower eyelid position after ptosis repair in patients with unilateral myogenic and aponeurotic blepharoptosis.They examined 78 patients who underwent upper eyelid In contrast,Kim et al. found that postoperative improvement of the lower scleral show was only significant after the frontalis sling procedure and not with levator resection.However, our study demonstrated a significant improvement in the lower scleral show after the levator procedure.Moreover, Teo et al. reported a significant improvement in the lower scleral show following the levator procedure, resulting in final symmetry of MRD-2 in 91.4% of patients with myogenic ptosis.
Demographic and clinical characteristics of patients enrolled in the study.
*Resulted from independent t-test.**Resulted from chi-squared test.
Sixty patients with blepharoptosis, comprising 33 with congenital and 27 with acquired ptosis, were enrolled in this study.The mean age for congenital ptosis patients was 21.61 ± 10.82 years, while it was 59.8 ± 13.73 years for those with acquired ptosis (Table1).