Proper pre-operative evaluation of ptosis type and severity, levator function, and concomitant ocular comorbidities are imperative in surgical management of ptosis.(1, 2, 11, 17) Furthermore, various ptosis repair types have been developed that differ based on anatomical approach as well surgical technique.(11) Ultimately, ptosis repair surgery is individualized, and aims to alleviate eyelid drooping and restore a normal visual field while maintaining symmetrical cosmesis.(18) We describe one of the largest cohorts of patients undergoing various ptosis repair techniques from a tertiary referral center over an extended follow up. Overall, while patient demographics, ptosis type and surgical technique differed significantly between the patients, primary outcomes consisting of residual ptosis (Margin-to-Reflex Distance 1 < 2.5 mm) and persistent postoperative ptosis necessitating re-do surgery did not differ between individuals in this cohort. This reinforces the concept that proper surgical selection based on patient demographics and preoperative clinical characteristics will result in good postoperative surgical outcomes.
The most common reason for acquired blepharoptosis in the adult population is dehiscence, stretching or disinsertion of the levator aponeurosis on the tarsal plate, resulting in involutional drooping of the eyelid.(19) In fact, senile changes of the levator aponeurosis result in up to 90% of acquired ptosis in the elderly population.(12, 20) Typically, involutional ptosis can be performed by an anterior aponeurotic advancement, however, posterior approach surgeries have become more recognized over the past decade.(21) Similarly, in this patient cohort, aponeurotic ptosis was the most common reason for surgical correction, with most of these patients undergoing Müller's Muscle-Conjunctival Resection correction with good primary outcomes. Furthermore, non-aponeurotic ptosis correction resulted in more postoperative residual ptosis and high referral rate for re-do corrective surgery. This is especially demonstrated in neurogenic ptosis, which may be attributed to defective innervation of the eyelid retractors, which may present a more challenging case to the operating surgeon.(22) Overall, preoperative Margin-to-Reflex Distance 1 and levator function differed significantly between ptosis type, underlying the pathophysiological mechanisms of each type of ptosis. (2) However, post-operative residual ptosis and referral for re-do surgery did not differ significantly, highlighting the efficacy of ptosis surgical repair regardless of ptosis type.(2)
On sub-analysis by surgical type, age, type and severity of ptosis, as well as preoperative levator function were significantly different between the four surgical groups, with FS patients demonstrating worse preoperative measurements. Furthermore, a majority of these patients had neurogenic or myogenic ptosis. Classically, patients with severe ptosis as well as poor levator function < 5 mm are candidates for frontalis suspension when adequate lid elevation cannot be achieved with standard levator resection or mullerectomy.(2) FS allows for direct elevation of the tarsal plate through contraction of the frontalis muscle, and is the treatment of choice for patients with chronic progressive external ophthalmoplegia (CPEO), muscular dystrophy, myasthenia gravis and nerve palsy.(23) In our patient cohort, FS patients demonstrated relatively more residual ptosis as well as referral for re-do surgery compared to the other surgical groups, however these values were not significant. Ptosis recurrence following FS has been well documented, especially following congenital ptosis correction, and occurs earlier in patients with worse preoperative Margin-to-Reflex Distance 1, due to increased force needed to lift the ptotic eyelid against gravity and tension of the orbicularis oculi muscle.(16, 24) Furthermore, FS can lead to postoperative lagophthalmos leading to exposure keratopathy, which may necessitate correction.(16) Overall, the other surgical techniques exhibited promising outcomes; all groups demonstrated improvement in Margin-to-Reflex Distance 1 levels regardless of ptosis type and preoperative ptosis severity. Furthermore, while postoperative residual ptosis was demonstrated in roughly a fourth of the patients on long term follow up, less than a fifth of patients were clinically significant and were referred for re-do ptosis correction, with no difference in referral rates between the groups. This success can be attributed to proper patient selection, preoperative evaluation and appropriate surgical correction.
When levator function is adequate, surgical repair of ptosis can be approached from an anterior or posterior approach depending on surgeon’s preference as well as severity of ptosis and levator function.(1, 17) Typically, patients with mild ptosis and adequate levator function are selected to undergo Müller's Muscle-Conjunctival Resection, with predictable outcomes and optimal cosmesis. However, patients with levator function worse than 12 mm, more severe ptosis, and ocular surface/cicatricial disease, which may be prohibit Müller's Muscle-Conjunctival Resection, may be better candidates for an anterior approach.(17) In our study, more patients underwent posterior approach surgery, with preoperative Margin-to-Reflex Distance 1 values significantly worse in the external approach patients. This was also demonstrated in a retrospective series of 272 procedures by Ben-Simon et al 2005, in which patients who underwent levator advancement had significantly worse preoperative ptosis.(8) Furthermore, both approaches were adequate for surgical correction of involutional ptosis. Chou et al also presented a large retrospective cohort study of 1519 patients that demonstrated worse ptosis in the anterior approach group, with an overall revision rate of 8.7%.(25) Our referral rate for re-do surgery was slightly higher in this cohort, as we included patients who also underwent frontalis suspension, which resulted in a relatively high referral rate of 20%. Overall, in our patient cohort, there was a small difference in postoperative Margin-to-Reflex Distance 1 values between anatomical approaches, however these differences were not significant. Moreover, there were no significantly different rates in residual ptosis or incorrected ptosis requiring re-do surgery, demonstrating the efficacy of both anatomical approaches.
Ptosis following ophthalmic surgery has been documented and is multifactorial in origin, believed to be due to effects of local anesthesia, postoperative swelling of the eyelid from regional edema and hematoma, as well as intraoperative eyelid manipulation or trauma, with the later more likely permanent.(14, 26–29) In our patient cohort, a history of anterior and posterior segment intraocular surgery significantly influenced primary outcomes, with these patients having higher referral rates for re-do ptosis correction. Furthermore, a large percentage of patients in our cohort underwent cataract extraction prior to ptosis correction. Involutional ptosis following cataract surgery has been well documented, and may due to intraoperative traction on levator aponeurosis as a result of speculum placement, which can be attributed to other standard ocular surgeries that utilize speculum placement.(28, 29) Ptosis following cataract surgery was demonstrated in a cohort of 220 patients who were randomly assigned to lid speculum usage during standard cataract surgery; the incidence of ptosis was significantly higher in the lid speculum group (44.4% vs. no speculum 23.3%, p < 0.05).(28) Overall, most patients following cataract surgery underwent Müller's Muscle-Conjunctival Resection with satisfactory postoperative outcomes, demonstrating effective correction of postoperative ptosis following the most common ocular surgery performed. At our center, we aim to reduce the incidence of postoperative ptosis following cataract surgery by avoiding excessive traction of the lid speculum and if it is possible, to perform cataract surgery prior to eyelid surgery.
This study is not without limitation, which stem from its retrospective nature. Furthermore, the data was collected from a large, university-affiliated tertiary referral center and included surgeries that were performed by different oculoplastic surgeons as well as resident physicians. Moreover, the number of patients is each ptosis group, as well as in each surgery group, were not uniform, aligning with the known distributions seen in the general population.
In conclusion, we present one of the largest cohorts of patients that underwent various ptosis corrective techniques. This study underscores the significance of a comprehensive preoperative history and clinical examination for identifying ptosis type as well as evaluating eyelid retractor function, which directs the operating surgeon when choosing the suitable technique.(2, 11, 28) In our patient cohort, overall surgical correction was effective regardless of ptosis type or severity, as well as surgical technique, with satisfactory postoperative Margin-to-Reflex Distance 1 levels and relatively low re-do referral rates, highlighting the importance of surgical technique selection. Furthermore, no significant differences in residual ptosis or referral for re-do surgery between all groups, as well as external vs. posterior surgery were demonstrated. Intraocular surgeries should be performed prior to ptosis correction to prevent residual ptosis from speculum traction on the eyelids. Overall, given the repertoire of surgical techniques available to the oculoplastic surgeon, ptosis corrective surgery can be completed with good success given that surgical candidate as well as operative procedure are chosen appropriately.