A new technique to prevent conjunctival prolapse in Asian patients for correcting severe blepharoptosis

A total of 70 patients (77 eyes) with severe blepharoptosis in the Medical Beauty Center of our hospital from January 2019 to December 2021 were collected. the patients with bilateral or unilateral severe blepharoptosis were selected. According to the method of operation, the patients were divided into two groups: the experimental group (34 cases, 38 eyes) and the control group (36 cases, 39 eyes). There was no significant difference in general data between the two groups (P > 0.05) (Table 1).

MRD1 (Margin Reflex Distance1,MRD1),MRD1 is the distance from the light reflex on the patient's cornea to the central portion of the upper eyelid margin with the patient gazing in the primary position. Normal MRD1 is 4–5 mm [4]. Those with MRD1 of 1 mm or less were defined to have severe ptosis [5, 6].

The patient had no prior history of blepharoptosis surgery, and no history of eyelid trauma, facial nerve dysfunction, mandibula-blink syndrome, blepharospasm, Horner syndrome or myasthenia gravis. All operations were performed by the same experienced surgeon, and all patients signed informed consent.

According to the MRD1 and the strength of the levator palpebral muscle of the patient, The amount of levator aponeurosis shortening needs to be evaluated. In patients with bilateral severe blepharoptosis, the double eyelid width is designed to be 4~5mm,the width of the double eyelid line is designed to be 4-5 mm, and the heavier the degree of ptosis, the narrower the design width of the double eyelid.In unilateral patients, the incision is designed according to the shape of the healthy eyelid or according to the requirements of the patients.

Fifteen minutes before surgery, obucaine eye drops were dropped into the eyeball for conjunctival surface anesthesia.The incision subcutaneous and pretasal infiltration anesthesia was performed by injecting the 2% lidocaine with 1:100,000 adrenaline.The skin was incised, excess orbicularis oculi were excised. and then,the superior edge of the tarsal plate was exposed. (Fig. 2a white arrow) The orbital septum was completely opened upward, the levator aponeurosis was cut at the superior edge of the tarsal plate. (Fig. 1b thin arrow) Then,the upper eyelid was turned over, and the 2% lidocaine was injected under the conjunctiva,which is also called ”the water separation”.The muller’s muscle was incised 8~10mm above the superior margin of the tarsus. (Fig. 1b thick arrow; Fig. 2a blue arrow) The structure between the muller’s muscle and conjunctiva was loose after the water separation. We separated into the fornix along the space between the conjunctiva and muller’s muscle until the white thickened fibrous connective tissue(CFS) was exposed.The upper 1/3 of the tarsal plate,muller’s muscle and conjunctival complex, CFS, levator aponeurosis and muller’s muscle complex (LM complex)are sutured together in the middle position of the upper eyelid using 5-0 silk thread (Fig. 2b-d).If the position of the middle fixation suture was appropriate, additional 4 fixation sutures were added on each side of the first fixation suture.In this way, the upper 1/3 of the tarsal plate, Müller's muscle and conjunctival complex, CFS and LM complex form a double "Ω" -shaped parallel double-loop structure,constituting a double-layered folded suspensory conjunctiva. (Fig. 1a-e). The double eyelid was made with 6 stitches of 7-0 nylon between orbicularis oculi muscleand the pretarsal fascial tissue, and then reinforced with the final skin-orbicularis oculi muscle-pretarsal fascia-orbicularis oculi muscle-skin closure with interrupted 7-0 protein sutures.

After anesthesia in the upper eyelid surgical area, the skin and orbicularis oculi muscle are carefully incised,The LM complex is then cut at the superior edge of the tarsal plate and separate into the conjunctival fornix until the CFS is exposed. According to the height of eyelid correction, the upper 1/3 of the tarsal plate, CFS and LM complex are sutured with 5-0 silk thread. Unlike the experimental group, no conjunctival tissue is included here. Finally, the incision is sutured layer by layer with 7-0 nylon thread and 7-0 prolene suture.

In addition, during the first week after surgery, a 3-0 silk suture is placed in the lower eyelid to close the palpebral fissure in both the experimental group and the control group After surgery, eye drops and ointment should be used until the eyelids are completely closed or until no signs of pupil are visible.

Two senior plastic surgeons jointly evaluated the correction of upper eyelid ptosis and the occurrence rate of complications such as conjunctival prolapse in two groups of patients. Patient satisfaction was assessed through self-evaluation scores, with a follow-up period of 3 to 12 months. Evaluation criteria for the correction of ptosis: Good correction: the upper eyelid of both eyes are highly symmetrical, the curve is smooth and natural, the upper eyelid covers the upper margin of cornea 1-2mm.General correction: the height of the upper eyelid is basically symmetrical, the radian is natural, the difference between MRD1 and normal value is less than 2mm, and the degree of ptosis is better than that before operation. Insufficient correction: the upper eyelid margin was covered to the upper margin of the pupil, and the difference between MRD1 and normal value was more than 2mm. Over correction: the upper eyelid margin was more than 1 mm above the corneal limbus [4]. Good correction and general correction are effective correction, correction efficiency = (good correction + general correction) / total number of cases × 100%.

In the evaluation of patient satisfaction, the subjective improvement degree of patients was > 70%, 50%~70% was general, and the patient satisfaction rate was = (satisfaction + general) / total number of cases × 100%.

The data of this study were analyzed by SPSS 26.0 statistical software. the measurement data were expressed by (X ±s), the counting data were expressed by T test, the counting data were expressed by (%), and the difference was statistically significant by χ 2 test.

Ptosis, a common eye disease, can have varying degrees of impact on individuals.Mild ptosis mainly affects one’s appearance, while moderate and severe blepharoptosis can partially or completely obstruct the visual field, significantly impacting the development of vision in patients. Over time, this condition can lead to other issues such as strabismus, amblyopia, head tilting and forehead lifting, and even spinal deformity and scoliosis [6, 7]. According to the literature, the incidence of amblyopia is approximately 2.8% ~ 3.2%.Among patients with ptosis, the incidence of amblyopia ranges from 23.9% to 56%, and the risk increases with the severity of ptosis [7‐9].

At present, there are many surgical approaches available for the treatment of blepharoptosis, These include the upper eyelid skin resection as well as more commonly used improved techniques such as frontalis muscle flap suspension, levator aponeurosis advancement, folding and shortening.By use of the muller’s muscle, tarsal resection, CFS and other surgical methods to correct ptosis, each of the above surgical methods has its own indications , advantages and disadvantages [10‐14]. In view of the severe ptosis discussed in this paper (The difference of MRD1 between the affected eye and normal eye was > 4mm) [4‐6], we used CFS+LM complex suspension operation to correct ptosis.

Currently, the use of levator palpebrae superioris muscle for ptosis correction is the most consistent with the physiological structure of the eye. This method is relatively simple, provides natural postoperative results,and has fewer complications [15]. However, in cases of severe ptosis where the functionality of the levator palpebrae superioris muscle is greatly impaired or non-existent, the correction effect of levator muscle alone can not be achieved. In such scenarios, the CFS suspension operation should be chosen as the preferred method for ptosis correction.The conjoint fascial sheath (CFS) was located in the intermuscular space between the anterior third of the superior rectus and the levator .Posteriorly, it extended from the fascia of the levator and superior rectus. Anteriorly, superficial and deep extensions of CFS continued approximately 2 mm to the superiorconjunctival fornix and then 2–3 mm distally along and beneath the palpebral and bulbar conjunctiva [16]. It was first applied to correct ptosis in 2002, and since then, this technique of CFS suspension has become increasingly popular for severe blepharoptosis [17, 18]. The CFS+LM complex suspension operation uses not only the dynamic strengthening principle of levator muscle shortening, but also the static suspension of tough CFS. This surgical technique ensures a coordinated connection between the initial static suspension height and the long-term muscle strength height, resulting in a relatively consistent upper eyelid margin height. Moreover, the suspension direction aligns with the movement direction of the levator muscle [15‐19], which is in accordance with the physiological characteristics of the human body.This approach has the advantage of minimal postoperative complications.

Firstly, what is the relationship between the correction of severe ptosis and conjunctival prolapse with CFS+LM suspension procedure? The study discovered that regardless of the chosen surgical intervention to correct ptosis, it aims to shorten and modify the tissue structure above the conjunctiva, without altering the length of the conjunctival itself.The normal width of the tarsal plate is 8~9mm, whereas the length of the Whitnall ligament from the upper edge of the tarsal plate is approximately 20~22mm [20, 21]. In patients with mild blepharoptosis, only the levator muscle is correctly advanced, folded or shortened, and the fornix conjunctiva overlaps only minimally, typically not extending beyond the upper eyelid margin. In severe blepharoptosis cases, we often advance 15~20mm or even utilize CFS to shorten the levator aponeurosis complex. At this time, the length of the folded conjunctiva in the fornix exceeds the width of the tarsal plate itself. The upper eyelid plate can not fully cover the entire conjunctiva, especially as the lateral side of the tarsal plate is narrower than the middle.This makes the conjunctiva more prone to prolapse,leading to a more notable prolapse of the upper eyelid’s lateral edge post-operation.This constitutes the anatomical basis for conjunctival prolapse in patients with severe ptosis after correction.

Secondly, under normal circumstances, a small fiber connection exists between the CFS and the superior fornix conjunctiva, creating a fornix suspension ligament that maintains the position and stability of the fornix conjunctiva. During severe blepharoptosis correction, the levator aponeurosis, Muller’s muscle and conjunctiva are carefully separated layer by layer, exposing the CFS .In this procedure, the fibrous ligament connecting to the conjunctiva is severed and disrupted, resulting in the loss of upward suspension support for the fornix conjunctiva. Additionally,a potential gap is formed between the levator aponeurosis and the conjunctiva due to the difference in lenth between the shortened levator aponeurosis and the excess conjunctiva [2, 3]. As a consequence of gravity, accumulated tissue fluid and blood graduallycollect in the space, leading to conjunctival prolapse.

Thirdly, the extensive dissection of the levator aponeurosis, muller’s muscle and conjunctiva during the operation,along with the removal of the fornix suspension ligament, increase the release of vascular inflammatory mediators.This, in turn, leads to changes in vascular permeability,a decrease in osmotic pressure, and obstruction of lymphatic reflux function [22, 23]. Consequently, there is continuous fluid exudation, edema, and vasodilation in the subconjunctival space. When the conjunctiva prolapse, it becomes trapped between the upper eyelid and the eyeball, hindering lymph and tissue fluid reflux.This further exacerbates conjunctiva edema, vascular dilatation, and swelling of the prolapsed conjunctiva [24, 23, 25], creating a vicious cycle that worsens conjunctival prolapse.

Based on the author's extensive clinical experience spanning over 20 years, it has been determined that prevention is the key to addressing the issue of conjunctival prolapse following severe ptosis correction. In this study, 70 patients (77 eyes) with severe ptosis were divided into an experimental group and a control group based on the different surgical methods employed. The experimental group underwent treatment with CFS+LM complex+ conjunctival suspension,while the control group received with CFS+LM complex suspension. The following key measures were implemented to prevent conjunctival prolapse during the operation in the experimental group:

The reason for preserving the LM complex at a distance of 8-10 mm above the upper edge of the tarsal plate is based on clinical and anatomical studies,which have demonstrated a gradual transition of the levator aponeurosis from a dense, tough and thick white connective tissue to a translucent thin film structure [20]. During the surgical procedure, the levator aponeurosis undergoes a color change from white to red. Forceful separation of the levator aponeurosis from muller’s muscle can easily lead to rupture or even perforation

The results of the 3 to 12 month follow-up in both the experimenta and the control groups indicated no significant difference in the rate of effective correction between the two groups (P > 0.05).However, the total incidence of complications in the experimental group was significantly lower than that in the control group (P < 0.05),particularly regarding the complication of conjunctival prolapse. The survey on patient satisfaction rates revealed that the experimental group had a significantly higher satisfaction rate compared to the control group (P < 0.05). The questionnaire survey further revealed that all patients with postoperative conjunctival prolapse in the control group were dissatisfied, accounting for 45.45% of the unsatisfied patients in the control group.This suggests that postoperative complications of conjunctival prolapse greatly affect patient satisfaction.

Preventing conjunctival prolapse during the severe blepharoptosis operation is crucial to avoid this complication.In this study, compared to CFS+LM complex suspension,the addition of conjunctival suspension to CFS+LM complex provides a double "Ω" conjunctival foldingtechnique.This methodhas proven effective in preventing postoperative conjunctival prolapse and other complications.Moreover,the procedure has a high feasibility, good corrective effect, and improves patient satisfaction after surgery.