2.1 Study design and patients
Forty-six out of 712 congenital blepharoptosis patients were found to have poor BP in the Shanghai Ninth People’s Hospital from November 2015 to December 2020. Four patients were lost to follow up, and the rest 42 patients were retrospectively reviewed in this study. Levator palpebrae complex (LPSC) suspension were performed by an experienced surgeon for all patients at a single center. Signed informed consent was obtained from all patients in accordance with the Declaration of Helsinki. Patients were aged 2-7 years with a mean age of 4.38±1.36 years. Fourteen patients were females and 28 patients were males. Twenty patients had bilateral blepharoptosis and 22 patients had unilateral blepharoptosis. Patients with a history of eyelid surgery, ocular deformity, jaw-winking phenomenon, congenital fibrosis of extraocular muscles and myasthenia gravis were excluded. Patients with a follow up of less than 3 months were also excluded. Ethical clearance was obtained from the Institutes Ethics Committee. Institutional review board approval and signed informed consent was obtained from all participants, in accordance with the Declaration of Helsinki.
2.2 Data collection and evaluation criteria
2.2.1 Patients’ data
The data of patients collected in this study included gender, laterality of blepharoptosis, age at the time of surgery, levator function (LF), severity of blepharoptosis, palpebral aperture height (PFH), visual acuity, marginal reflex distance 1 (MRD1), marginal reflex distance 2 (MRD2), presence or absence of lagophthalmos, BP, family history of blepharoptosis, ocular motor movements and associated ophthalmic or systemic problems. For postoperative evaluation, best-corrected visual acuity, postoperative refractive errors, PFH, MRD1, MRD2, lagophthalmos, symmetry of eyelid height, upper eyelid contour, length of follow-up, and complications such as dry eye, ecchymosis, exposure keratitis and lagophthalmos were recorded.
2.2.2 Blepharoptosis evaluation
LF was considered excellent if eyelid excursion was > 12 mm, good if 8–12 mm, fair if 5–7 mm, and poor if < 5 mm, respectively [10]. LF was evaluated by the excursion of the upper eyelid margin from extreme downgaze to extreme upgaze when patient’s eyebrow was pressed to eliminate the interference of frontalis muscle [11]. The severity of blepharoptosis was classified as mild (1-2 mm), moderate (3-4 mm) or severe (> 4 mm), which were associated with good, fair, and poor LF, respectively [12]. In this study, the mean preoperative LF was 2.55±1.09 mm and the mean severity of blepharoptosis was 5.48±1.36 mm.
2.2.3 BP evaluation
An ocular deviation of > 4 mm was previously considered a normal response [1]. However, we observed that individuals with normal palpebral-oculogyric reflex had positive BP during shallow sleep (5 min after falling asleep), but poor and sometimes even negative BP during deep sleep (30 min after falling asleep). A small ocular deviation was observed in individuals with poor BP during both shallow and deep sleep.(Fig.1,2) Based on previous studies and our observations, BP was considered normal if the ocular deviation was > 4 mm during volitional eyelid closure or shallow sleep, and poor if < 4 mm. At the preliminary screening, BP was checked on attempted light closure of the eyelid after elevating patient’s upper eyelids using the finger and thumb of one hand, and 46 out of 712 consecutive pediatric blepharoptosis patients were found to have poor BP. In order to minimize biases (such as pseudo-reflex and lack of cooperation), a second examination was performed on patients with negative BP at 5 and 30 min of falling asleep using the same procedures, respectively. Negative responses were also observed in these 46 patients.
2.2.4 Surgical outcomes
The surgical outcomes were evaluated by postoperative MRD1, which was defined as excellent if it was ≥ 3 mm, good if 2-3 mm, and poor if < 2 mm, respectively. Recurrence was defined as a decrease in MRD1 to less than 50% of initial postoperative MRD1 [13]. To evaluate postoperative eye blinking status, LipiView interferometer which is able to measure the incomplete blink ratio was applied [14].
2.3 Surgical methods
Surgical design: We have designed levator palpebrae superioris complex (LPSC) suspension, which applies the levator muscle and the fascia sheath complex above the level of the whitnall ligament to suspense the drooping eyelids. (Fig.3,4,5)
Surgical procedure: Levator palpebrae superioris complex (LPSC) suspension were performed under general anesthesia. After marking the desired upper eyelid crease line, the skin was incised to the superior border of the tarsus through the orbicularis muscle and extended medially and laterally. The orbicularis muscle was dissected to identify the orbital septum. The inferior skin and pretarsal orbicularis muscle flap were dissected from the tarsal plate. The orbital septum was incised horizontally with a cautery device or scissors and preaponeurotic fat was identified. Excessive preaponeurotic fat was removed with electrocauterization. The levator aponeurosis and Muller’s muscle were dissected from the upper border of the tarsal plate and conjunctiva until the Whitnall ligament could be identified. Upward detach the levator aponeurosis from the Müller muscle until over the fornix about 5 mm, to expose appropriate region of the conjoint facial sheath(CFS). Keep the connection between Levator muscle and Conjoint facial sheath intact. Then fully dissociate the LM complex from the ligament level and pulled down to the tarsal plate. Suspend and suture the upper margin of the tarsal plate to the LM complex at 1 mm to 2 mm below the limbus. Sutures were adjusted if the eyelid height was unsatisfactory. The skin incision was closed incorporating 3 or 4 deep bites through aponeurosis. A lower eyelid traction suture and topical antibiotic ointment were used. (Fig.6,7)
2.4 Postoperational treatment
All patients received Levofloxacin and Prednisolone acetate eye drops 4 times/day and Sodium Hyaluronate eye drops 6 times/day for 7 days after surgery. Eye ointment containing Recombinant bovine basic fibroblast growth factor (bFGF) was administrated 3 times daily, and Eryphilin was administrated once daily at night. One week later, Sodium Hyaluronate eye drops, bFGF-containing eye ointment and Eryphilin were administrated 4 times, 3 times and once at night per day for 3 months.
2.5 Statistical analyses
Descriptive statistics were expressed as mean ± standard deviation. χ2 test was performed for discrete and categorical data. Paired t test was performed to evaluate changes in surgical outcomes (PFH, MRD1, etc.). P values less than 0.05 were considered statistically significant.