Journey of frontalis muscle advancement in severe blepharoptosis: Review of the techniques, modifications, and outcomes

Abstract

We aimed to review the degree of standardization of frontalis muscle (FM)–orbicularis muscle advancement techniques in the management of severe congenital blepharoptosis and also study the evidence which supports the procedure correcting blepharoptosis. The undisputed rationale of all types of brow suspension in the management of severe blepharoptosis is based on the concept that slings are the conventional way to simultaneously suspend a ptotic eyelid and transmit the contractile action of the FM to the tarsal plate. Traditionally, frontalis suspension using sling has been used to treat patients with severe congenital blepharoptosis with poor levator function; however, postoperative lagophthalmos, forehead scarring, and recurrence remain major concerns. Since the early 80s, a significant number of consecutive articles have suggested that the eyelid can be effectively suspended by directly suturing FM to the tarsal plate. This review article intends to evaluate the level of standardization of FM advancement techniques in the management of severe blepharoptosis. 'In addition, to determine if the procedure should be performed in a standard manner, and is there enough evidence available to recommend FM advancement as a useful surgical technique.

A multitude of surgical techniques for the correction of blepharoptosis have been developed, and the modality of choice depends on the extent of eyelid excursion. Severe upper eyelid blepharoptosis associated with poor or absent levator palpebrae superioris muscle function has been managed traditionally with “frontalis suspension” using different slings connecting the tarsal plate to the frontalis muscle (FM). Frontalis slings work well; however, postoperative lagophthalmos with its sequelae of complications and recurrence of ptosis in the long term remains a major concern.

In 1992, Song and Song[1] innovated the concept of “frontalis transfer” via direct transplantation of FM to the tarsal plate for severe blepharoptosis. Later, in 1996, Knize[2] first described interdigitation of the fibers of the orbital portion of the orbicularis oculi (OO) muscle and FM. Based on this, in 1998, Park et al.[3] studied and introduced three kinds of superior-based muscle flaps for different degrees of blepharoptosis, including interdigitated OO–FM flaps. Later, Lai et al.[4] put forward the concept of “frontal orbicularis oculi muscle (FOOM) flap” to denote the interdigitation and crosslinkage of the horizontally oriented orbital OO muscle (OOM) fibers and longitudinally oriented FM. In comparison to the FOOM flap, the FM transfer technique directly connects the FM flap with the tarsus without disturbing OOM.

This review article intends to describe the evolution of FM transfer techniques in the correction of severe blepharoptosis and evaluate if there is enough evidence to recommend FM advancement as a useful surgical modality.

Methods

A literature review was performed in PubMed, MedlinePlus, and Scopus databases using the following keywords: “frontalis muscle flap,” “frontalis muscle transposition,” “frontalis muscle advancement,” “frontalis transfer surgery,” “frontalis muscle and ptosis correction,” “fronto-orbicularis muscle surgery,” “orbicularis muscle flap,” “frontalis muscle flap in severe ptosis,” and “ptosis.” One keyword/phrase from each cluster was used, unless repeated. All articles consisting of ≥ 10 patients, published before October 2023, were screened and evaluated, and then relevant studies were included. Data retrieved included number of patients and eyelids operated, characteristics of ptosis, type and variation of the flaps used, time of follow-up, outcomes, and complications [Fig. 1 and Table 1].[5,6,7,8,9,10,11,12,13,14,15,16]

Figure 1.

Flowchart of the articles reviewed and analyzed

Table 1.

Patients’ demographics, type of study, number of patients, complications

Reference number	Year	Eyes operated		Type of ptosis		Flap		Results assessed	Satisfactory outcomes	Unsatisfactory results? Complications/ corrective surgeries	F/U
		Total	U/B	Congenital	Acquired
5	1988	133	111/22	126	7	Frontalis myofascial flap		1) Normal opening and closing of the palpebral fissure 2) No more than 1 mm of asymmetry in the height of the upper eyelid margin 3) Symmetrical eyebrows, angles of the cilia, arches of the upper eyelid margin, as well as width of the upper eyelid fold of both eyes
6	1992	36	18/18	33	3	Tripartite FMF transposition		1) Berke's criteria 2) Forehead sensations		Entropion (1) Lagophthalmos (1) Lid lag >3 mm (4) Overcorrected cases were repaired by frontalis myotomy
8						FMF (3)	FMF + OOM interdigitated portion of OO–frontalis muscle (5)	Souther et al. • No >1 mm of asymmetry in the height of the eyelid margin • <2 mm below the upper border of limbus in the primary position with normal opening and closing of palpebral fissure	6/8	Undercorrection (2/8)
9	1999	109	46/63	100	9	Forked frontalis muscle aponeurosis		Southern et al. Movement of the eyelid, upper palpebral fold, different height of upper palpebral rim, arc of upper palpebral rim, lagophthalmos	Good in 95% of cases
14	2002	13	5/3	All recurrent ptosis		FMF (8)	OOM (5)	Souther, Jordan, and Anderson	7/8	Undercorrection (2/8) To correct the undercorrection, the caudal portion of the flap was resected and reattached under tension
21	2007	130*	NS	All	-	FMT (80)	LPSR (50)	Improvement in degree of ptosis		Undercorrection (16/80) Overcorrection (4/80) Entropion (4/80)
22	2008	19*	18/4	All	-	Frontal muscle flap overlapped with an inferiorly based orbital septum flap		Souther, Jordan, and Anderson	15/17	Reduced eyelid excursion in extreme upward and downward gaze (transient)	6–18 months
24	2009	38	29/9	25 Severe ptosis and four recurrent ptosis		Frontalis- orbicularis Oculi muscle flap shortening		(1) Less than 1 mm of asymmetry in the height of the upper lid margin in unilateral cases; (2) no >2 mm below the upper border of the limbus of the primary position in bilateral cases, and (3) normal opening and closing of the palpebral tissue and a symmetrical eyebrow	82%	Transient undercorrection	10–12 months
26	2008	35	NS	NS	NS	FOOM flap-shortening technique		Souther et al.	30/35	Undercorrection (5)	5–55 months
27	2011	26	18/4	Recurrent ptosis (12) Congenital (9) Acquired (3)		Direct tarsus to frontalis muscle without flap creation		Upper lid margin to central corneal reflex distance of at least 3 mm in bilateral cases and a difference of less than 1 mm in unilateral cases, while the patient relaxed the frontalis power	86.4% (at 1 month)	Undercorrection (3/26) Overcorrection (1/26) Entropion (1/26) Entropion cases were corrected by displacing the suture lower on the tarsus Both under- and overcorrection cases underwent readjustment of suture	6–28 months
29	2012	83	39/22	All	-	FMF suspension		Correction of blepharoptosis, healing, complications, and lagophthalmos	Satisfactory	Undercorrection (11/83) Unnatural lid curvature (4/83)	3–60 months
30	2013	81	51/15	Congenital (65%) Acquired (35%)		FOOM flap (65)	Double- breasted FOOM flap advancement (16)	Souther and Vistnes A good result is defined as follows: (1) >1 mm asymmetry of the upper lid margin in unilateral cases and (2) not <2 mm below the upper border of the limbus in bilateral cases	Good results in 81.8%	Undercorrection or recurrence rate (14.8%)	6–60 months
31	2014	30	14/8	All	-	Direct frontalis muscle advancement		These included: palpebral FW, MRD1, ptosis, Bell's reflex, levator, and orbicularis function The presence of complications, flap function, and palpebral contour were evaluated on the follow-up visits		Anterior displacement of the upper eyelid in extreme upgaze (pop eyelid) (7/30)	6–97 months (mean 27 months)
32	2014	217	NS	126	17	FMT	Müller–aponeurosis composite flap advancement		Equivocal results	Undercorrection (7.4%) Asymmetry (7.4%)

FMF=Frontalis muscle flap, FOOM=Frontal orbicularis oculi muscle, F/U=Follow-up, FW=Fissure width, MRD1=Margin–reflex distance 1, OOM=Orbicularis oculi muscle, U/B=Unilateral/bilateral, FMT=Frontalis muscle transfer, LPSR=Levtor palpebrae superioris resection

FM: Surgical innovations

Treatment of severe blepharoptosis with poor levator function presents a therapeutic challenge. The frontalis suspension technique, introduced by Wright[17] and later popularized by Crawford,[18] is the most widely used surgical technique worldwide for the management of severe blepharoptosis with poor levator function. Various modifications have been made in the technique and material; however, the common shortcomings remain. In comparison, frontalis transposition techniques offer definitive advantages over frontalis suspension in the management of severe blepharoptosis [Table 2]. Studies have shown that the better the FM function is, the more satisfactory the outcome is. Hence, Liu et al.[19] concluded that the outcome of the correction depends on the function of FM preoperatively in the patient.

Table 2.

Superiority of “frontalis muscle transposition” techniques over “frontalis sling suspension”

A) Unavoidable complications after “frontalis suspension”

• Ptosis in superior gaze

• Moderate to severe lid lag on downgaze

• Lagophthalmos

B) “Frontalis muscle transposition” has the following advantages over “frontalis sling suspension”:

• Mild or no ptosis in superior gaze

• Mild lid lag on downgaze

• Minimal early transient lagophthalmos

• No notching deformity of the lid margin

• No impediment of wrinkling or blinking

• No need to overcorrect intraoperatively

• No donor site morbidity

C) “Frontalis muscle transposition” flaws

• Risk of transient mild hypoesthesia from injury to the supraorbital nerve during vertical incision of the frontalis muscle. To decrease the chances of this injury, more the transacted flap is elevated laterally, more obvious will be tenting of the lid margin

• Incomplete wrinkling of forehead occurs after frontalis transposition, making it relatively contraindicated for cases with unilateral ptosis and deep forehead wrinkles

• Slightly lower position of eyebrow in superior gaze in unilateral cases

• Unreasonable to expect symmetrical and synchronous movement of the upper lid in unilateral cases as not being a pure eyelid elevator, frontalis acts like a window blind that tugs the eyelid straight up as opposed to up and back pull of levator

Fergus[20] was the first one to utilize FM transfer in 1901 to treat a case of bilateral severe congenital ptosis. Using a brow incision, a large FM flap was created and attached to the lower portion of the tarsus.[20] However, in 1982, Song and Song[1] described in detail the use of an L-shaped, medial-based FM flap to correct severe ptosis. Since their pioneer description, the use and various modifications of the FM flap transfer in the management of severe ptosis have been extensively studied and reported. The major shortcomings with the pioneer method of FM transfer described by Song and Song[1] were loss of wrinkle, depression on the forehead, intraoperative bleeding, poor visibility of the dissection plane, requirement of two incisions, a considerably longer distance of FM to the tarsal plate, and chances of trauma to supraorbital neurovascular bundles. To address these deficiencies, FM flap without vertical incision, tripartite FM technique,[6] and myofascial techniques[5,21] were tried, however, with no definitive superior advantages.

Few fibers of the FM and its fascia have connections and interdigitations with the orbital fibers of the OO in the brow region.[22] This interdigitated network of fibers is relatively mobile over the periosteum due to the presence of areolar tissue between the FM and the periosteum. Based on these anatomic observations, in 1998, Park et al.[3] put forward the idea that a superiorly based OOM flap or interdigitated OO–FM flap, when advanced and attached to the tarsus, can elevate the severely ptotic eyelid more dynamically.

For the superiorly based OOM flap, the authors have performed a biplanar dissection in the subcutaneous and sub-orbicularis plane.[3] Subcutaneous dissection is continued till the inferior margin of the eyebrow, whereas in a plane between the orbicularis and the septum, dissection is continued till the supraorbital rim. Two parallel medial and lateral cuts were given over the dissected orbicularis to form a superiorly based OOM flap. Whereas for creating interdigitated OO–FM flap, subcutaneous dissection is carried out further as far as 0.5 cm above the superior margin of the brow and dissection between the orbicularis and the septum is carried out till the supraorbital rim. The muscle flap between the two planes is elevated, and two parallel medial and lateral cuts are given to create a rectangular interdigitated OO–FM flap.[3] Care must be taken to prevent injury to the orbital septum (OS), and a medial cut must be given 5 mm lateral to the supraorbital notch to prevent injury to supraorbital neurovascular bundles. Both techniques offer the advantage of not injuring the temporal branch of the facial nerve because the operative field is limited to the brow region. In addition, the technique offers the advantages of a single incision on the supratarsal fold, no depression on the forehead, and preservation of function of the FM.

Following this first description and the integration of orbicularis, different variants of the original Song's flap and OO–FM complex were reported. Various important aspects are described below.

Anatomy and related surgical aspects

The occipitofrontalis (epicranius) muscle is the only muscle capable of elevating the eyebrow and critically determines the anatomy, functionality, and aesthetics of the forehead, eyebrow, and eyelid. It has two bellies, anterior (frontalis) and posterior (occipitalis), referred to as separate muscles, which function independently. The frontalis belly is described as a thin and quadrilateral muscle, adherent to the superficial fascia with no bony attachments. It attaches to the eyebrow, where its medial fibers interdigitate with the fibers of the procerus, intermediate fibers blend with corrugator supercilii and OOM, and lateral fibers blend with OO over the zygomatic process of the frontal bone. Superiorly, FM invests within the galea aponeurotica, whereas laterally, FM attenuates near the temporal ridge, where the galea blends with the temporoparietal fascia at the conjoined tendon.[22]

Among the important neurovascular structures, the frontal branch of the facial nerve innervates FM. It enters the muscle from the lateral and deep aspect at the level of the temporal line of fusion of the forehead. The supraorbital neurovascular bundle rises at about 2.5–3.0 cm from the midline and all the branches of supraorbital nerves are usually located within 2.0–3.2 cm from the midline at the level of the orbital rim, while the transverse supraorbital vein usually courses at the level of the orbital rim.

• Plane of dissection

• • OOM

Typically, an eyelid crease incision is used to dissect and separate OOM from OS and reach up to the superior orbital rim. Technically, the dissection of the OOM up to the superior orbital rim is easy. Alternatively, dissection can be performed after opening OS and maintaining the plane of dissection below the septum. In further modifications, when OO is used as an extension of the flap or as a component of the frontalis OO complex, the orbicularis also needs to be dissected on the subcutaneous plane from the overlying delicate preseptal skin.

• • FM

A more challenging dissection is encountered in the brow area and above the superior orbital rim. First, a transaction of the orbicularis muscle is needed at the level of the superior orbital rim. Further, to create the FM flap, a biplanar dissection is required to be performed in subcutaneous and subgaleal planes. Dissection in this area carries the risk of bleeding from rich vascular plexuses in a subcutaneous plane or from trauma to the transverse supraorbital vein above the level of the superior orbital rim.[23]

Ramirez and Peña[24] insisted a clear and definitive surgical plane can be created that divides FM from the orbicularis, which is apparent with greater magnification than that possible with the naked eye. However, Hwang et al.,[25] in a cadaveric study, performed the histopathological evaluation of the OO–FM complex and contended that it is not easy to separate both the muscles because of tight interdigitations between the fibers of orbicularis and frontalis.

• Width and shape of the flap

The width of the flap is determined by multiple parameters such as age of the patient, horizontal palpebral fissure length, severity of ptosis, and surgeons’ preference. Usually, the width of the flap should be less than the width of the horizontal palpebral fissure.

The shape of the flap, specifically the distal portion, needs to be designed in a way to match the normal arch-shaped curvature of the attachment of levator aponeurosis with the tarsal plate.[26]

• Role of OS

Various surgeons have handled OS in different ways. The majority of surgeons do not prefer to violate the integrity of OS and keep their plane of dissection above OS.[5,9,26] Others have incised OS as a part of modification in their technique either with[6] or without[9,27] removal of the preaponeurotic fat pads. This plane of dissection below OS provides a clearer bloodless field till the superior orbital rim. Moreover, few techniques have utilized OS as a part of the frontalis orbicularis muscle flap component to reinforce it.[10,11,28] Some authors used it as a pulley to change the direction of movement tangentially to prevent ectropion or entropion.[29]

• Incisions

Depending upon the type of flap, the number of incisions has been decided. In the technique, like tripartite FM flap transposition, an additional forehead incision along with lid crease incision has to be marked, affecting the forehead sensation in the post-op period. Usually, a lid crease is marked across the upper eyelid at a height symmetrical to that of the opposite upper eyelid in unilateral ptosis. In bilateral ptosis, the proper lid crease incision is drawn 5–8 mm from the lash line according to the width of the tarsal plate, as a double-eyelid plasty for the Asian eyelid.[30]

• Eyelid Position

The aesthetic result of surgical correction for ptosis post-FM transfer procedures is determined by the symmetry of the curvature of the two lid folds, which in turn is decided by the intraoperative position of the upper eyelid fixation. The standard guidelines followed by nearly every surgeon for correcting severe ptosis involve maintaining the central portion of the upper eyelid 1mm higher than that of the normal side in unilateral cases. While for bilateral cases, the central portion of the upper eyelid should be at the upper border of the limbus in the primary position. However, as the globe position deviates under general anesthesia, for most orthophoric patients, a combination of exotropia and hypertropia is reported.[31] Therefore, while performing surgery under general anesthesia, there remains a concern about the ideal fixation point and it might not be appropriate to fix the position of the upper eyelid margin at this unified level. Some studies stated that for children with severe upper eyelid ptosis, precise preoperative marking and individualized design of the fixation level of the upper lid margin are crucial for achieving better surgical outcomes.[32,33] This concern requires further future prospective studies to compare the ideal position for patients operated under general anesthesia.

• Role of levator aponeurosis

Although the role of levator aponeurosis alone in correction of severe blepharoptosis is insignificant, Medel et al.,[34] in their modified FM flap (FMF)-pulley technique, used levator aponeurosis as a pulley to change the vector of FM and showed more stable outcomes with the technique. Vasquez et al.[35] also concluded that a good functional and aesthetic long-term result was achieved in the FMF-pulley group compared to the FMF-direct group. Some authors also investigated the use of a transposed distal levator aponeurosis flap as a frontalis sling for patients with Marcus-Gunn jaw winking phenomena requiring levator excision or for those with poor levator function.[36]

Discussion

The role of the FM as a dynamic muscular pulley in correcting severe blepharoptosis has undergone significant evolution over time. While the FM suspension technique remains the oldest practiced method, it has not been without its challenges, including persistent lagophthalmos, lid lag in down gaze, recurrent ptosis, and visible forehead scarring. In response to these complications, numerous studies have sought to utilize the mimetic muscle in innovative ways to address these issues.

Many studies have explored modifications to the existing FM flap advancement technique, highlighting the advantages and shortcomings, along with modifications and innovations. Herein, the authors discuss the following evolution and modifications of different surgical techniques of FM flap advancement for repair of severe ptosis.

• 1.Tripartite FM flap[6]

A supero-laterally based L-shaped frontalis flap is designed on the forehead in a sub-dermal plain. The horizontal limb is extended 5 mm horizontally and the vertical limb is designed according to the degree of ptosis and the height of the forehead. For the exposure of tarsal plate, a strip of pre-tarsal OO is excised. In addition, a portion of OS is incised and preaponeurotic fat removed. After bringing the frontal flap down to the tarsal plate, two vertical cuts were made to divide FMF into three parts [Fig. 2a].

Figure 2.

(a) Tripartite frontalis flap – the figure illustrates the FM flap divided into three segments and sutured to three different portions of the tarsus, ensuring redistributed upward pull. (b) FFMA – the figure illustrates vertical transaction of FM aponeurosis to form forked flap of the aponeurosis. FFMA = forked FM aponeurosis, FM = frontalis muscle, OOM = orbicularis oculi muscle, OS = orbital septum

Highlights: Direct transposition of the FM to the tarsus is an effective technique for correction of blepharoptosis with poor levator function; however, it often results in “tenting” deformity of the lid margin. “Lid tenting” in primary gaze, which is accentuated further in superior gaze, is because of the upward pull by FM. In an effort to prevent tenting, caudal portion of the frontalis flap is divided into three portions and then sutured at the medial, middle, and lateral portion of the tarsus to distribute frontalis upward pull in a more evenly manner.

Advantages: Tripartite flap evenly redistributes the upward pull from FM, hence resulting in a better eyelid contour with no “lid tenting.”

Shortcomings: Transient lid lag in inferior gaze and limited utility in unilateral cases because of asymmetrical and asynchronus movement of the upper eyelid

• 2.Orbicularis oculi muscle (OOM) and OS flap[10]

FM has a fascial connection to OOM, and OS is a firm fascia that arises from the arcus marginalis and is adhered tightly to the posterior part of OOM in lower two-thirds of the eyelid. Based on this concept, the authors applied the idea of advancing OOM and OS as a single flap to the tarsal plate, hence transmitting the indirect FM action more effectively.

Highlights: The eyelid is supended by the shortened OS, as in fascia lata suspension, and in addition, the shortened OOM has more effective transmission of FM action.

Advantages: Only a single incision is needed along the double fold line. The single unit advancement without separation of OOM–OS provides more tensile strength to the muscle and septum, and hence improves indirect FM action transfer.

Shortcomings: Transient eyelid lag and lagopthalmos is the shortcoming, which is expected to improve over a period of time. Excessive streching of OOM and OS over a period of time might lead to undercorrection.

• 3.Superiorly based, interdigitated OO frontalis-based flap (OOM–FM)[3]

Some fibers of FM and its fascia have connections and interdigitate with the orbital portion of OOM at the eyebrow region. The interdigitated muscle fibers are relatively mobile upon the periosteum because of the presence of loose areolar tissue between the posterior fascia of FM and the periosteum. Hence, a superiorly based, interdigitated OO–FM-based flap, if advanced and attached to the tarsal plate, can elevate the tarsal plate more dynamically.

Highlights: It lifts up the lid dynamically by the natural contraction of FM and statically by the suspension effect of the muscle flap itself, that too without injuring the temporal branch of the facial nerve as the flap creation involves no medial vertical FM incision.

Advantages: A single incision on the supratarsal fold, hence natural-looking supratarsal fold and natural contour of the upper lid postoperatively, preservation of function of FM, and no risk of neurovascular injury

Shortcomings: Bleeding and hematoma formation during subcutaneous dissection are the shortcomings. Other shortcomings are undercorrection and risk of recurrence over a period of time in cases with absent or weak eyelid excursion. In addition, ptosis with upward gaze and lagophthalmos in downward gaze may still occur since the pull exerted by FM for elevating the lid tends to pull the lid away from the globe.

• 4.Forked FM aponeurosis (FFMA) suspension technique[7]

Four lines were drawn including an incision line along the desired palpebral fold, two perpendicular lines through the supraorbital fossa and the lateral part of the eyebrow, and a horizontal line about 10 mm above the eyebrow. A subcutaneous dissection at the forehead and eyebrow and dissection of the orbicularis muscle and OS in the upper eyelid were performed. After retracting the eyelid skin above the incision, FM aponeurosis is drawn down to the upper rim of the tarsus. Finally, a vertical incision about 5–8 mm in length (according to the tightness of FM aponeurosis) is made to form a forked flap of the aponeurosis (FFMA). At last, the central area of the upper rim of the tarsus is sutured to the upper point of the longitudinal incision on FFMA. The lateral parts of the tarsus are fixed respectively to the two lobes of FFMA [Fig. 2b].

Highlights: During frontalis transposition, to minimize injury to FM and preserve its normal function of active contraction, the authors invented FFMA suspension technique.

Advantages: Maintenance of good function and postoperative mobility of FM, protection of supraorbital vessels, averting possible hematoma, and avoidance of loss of frontal skin sensation are the advantages. In addition, FFMA can reduce this arc-like tension on the incision line by lengthening the arc line and delivering the tension along a longer line to three to five fixed stitches, hence reducing the incidence of recurrence of blepharoptosis.

Shortcomings: As with the standard technique of frontalis transposition, there is slow movement of the upper eyelid on downward gaze; eyebrow asymmetry in cases of unilateral blepharoptosis remains another weak point with FFMA.

• 5.FM transfer using tunnel[9]

Using two incisions at the inferior margin of the eyebrow and the supratarsal area, FM was elevated and a tunnel linking these two areas was created. Subsequently, FM flap was drawn downward through this small tunnel beneath OS and fixed to the tarsal plate at two to three points [Fig. 3a].

Figure 3.

(a) FM transfer using tunnel – the figure illustrates two incisions, one at the sub-brow region and the other at the lid crease, followed by creating a tunnel. FM drawn downward through this tunnel beneath OS and sutured to the tarsal plate. (b) FM flap overlapping with an inferiorly based OS flap – the figure illustrates a frontal muscle flap overlapping with an inferiorly based OS flap. FM = frontalis muscle, OS = orbital septum

Highlights: A more dynamic pull and elevation can be achieved using a small tunnel beneath OS and transferring FM action on the tarsus.

Advantages: Better functional outcomes in terms of correction of ptosis in comparison to other methods of frontalis transfer

Shortcomings: Undercorrection, transient lagophthalmos, lid fold deformity, and entropion remain points of significant concern.

• 6.Frontal muscle flap overlapped with an inferiorly based OS flap[10]

Above the tarsus, OS has adhesions with the levator aponeurosis. The septal extension, which lies between OOM and the levator–tarsus junction, begins at the adhesion of OS to the levator and extends to the ciliary margin. By suspension of a frontal muscle flap overlapped with an inferiorly based OS flap, the dynamic frontal and levator muscles are connected by OS, which avoids damage to the levator muscle. Therefore, suspension of the upper eyelid by overlapped suturing of an FM flap and an OS flap can give a very firm effect [Fig. 3b].

Highlights: FM flap connected to OS is a powerful motor unit, as it not only corrects the ptosis but also keep the completeness of the eyelid, making it more suitable physiologically and more characteristic biomechanically and maintaining the eyelid posture in both static and dynamic states better. Over a period of time, patients eventually learn to set the eyelid position at the appropriate functional and aesthetic level.

Advantages: This technique avoids injury to the levator muscle of the upper eyelid with a simple learning curve, relatively less trauma, and a better effect.

Shortcomings: Transient lifting of the eyebrow or closing of the eye with substantial force in the early postoperative period

• 7.FOOM[4,11]

In this technique, authors created two perpendicular cuts at the lateral and medial sides of OOM with a width of less than the palpebral fissure, hence creating a superiorly based, rectangular FOOM flap. The preseptal part of OOM, OS, and the distal frontalis fibers as an entity are then advanced downward on the tarsus as a single flap. The distal portion of the flap is fashioned and adjusted to have a natural arch contour like the levator aponeurosis attachment [Fig. 4a].

Figure 4.

(a) FOOM flap – the figure illustrates superiorly based OO–FM flap advanced and sutured to the tarsal plate. (b) Double-breasted technique – the figure illustrates division of OOM flap into superior and inferior flaps. The upper flap is being sutured to the tarsus and the lower flap is sutured over the upper flap, achieving double-breasted closure. FM = frontalis muscle, FOOM = frontal orbicularis oculi muscle, OO = orbicularis oculi, OOM = orbicularis oculi muscle

Highlights: It achieves antagonistic equilibrium with ideal biomechanics by debilitating eye closing power and enhancing eye opening power. The shortened FOOM flap provides an elastic and contractible unit to pull up the eyelid, instead of a rigid frontalis sling. Therefore, the balance of eyelid movement can be achieved with natural look and ideal biomechanics.

Advantages: The FOOM flap-shortening technique is more natural looking and effectively transmits the power of the compensatory hypertrophic FM to the supratarsal area through the junctional lineage of FM and OOM. Rate of undercorrection and rate of recurrence remain less compared to the conventional technique.

Shortcomings: FOOM flap-shortening technique also has a component of temporary lagophthalmos. Long-term follow-up results are not available on the possibility of the weakening FM–OOM linkage.

• 8.Double-breasted technique[37]

In this technique, the author has modified the FOOM flap by dividing it into an upper muscle flap and a lower muscle flap. The upper flap including the OS has been elevated, such that its base extends to the upper orbital rim and its distal width matches that of the tarsal plate. This upper flap is then sutured to the tarsal plate, such that it form an arc. The remaining lower muscle flap is sutured over the upper flap in a position of slight tension to achieve double-breasted closure [Fig. 4b].

Highlights: Formation of two OOM flaps, superior and inferior, results in immediate complete eyelid closure in the early postoperative period. The technique also allows dynamic, powerful eyelid opening action, hence preventing the most common and concerned complication of lagophthalmos.

Advantages: Patients with double-breasted flap show immediate closure of the eyelids in the postoperative period, avoiding the need of Frost suture and artificial tears. In this technique, the patient is able to move the ptotic eyelid with the help of a superiorly based OOM flap that is continuous with OS and FM, thus preventing lagophthalmos.

Shortcomings: As a result of excessive stretching of OOM, there might be some amount of undercorrection over the period.

In this systematic review article which focuses solely on the use of FM advancement in correction of severe ptosis, the authors found significant variability in the number of incisions, plane of dissection, position of eyelid, and different locations of FM flap attachment. Furthermore, this article provides the relative comparison of different surgical techniques utilizing the action of FM for lifting of the eyelid.

We also observed that most of the studies have not explained the need for revision surgery. Exciting publication on this topic has emphasized more on the surgical techniques rather than the longer follow-ups. This review was limited by the nature of different studies – case reports, large case series, retrospective studies, and very few prospective comparative studies. However, the hypotheses generated from these different techniques have provided useful parameters for future prospective studies and potential modifications in clinical practice for management of severe blepharoptosis.

Thus, the authors of this review advocate for standardizing frontalis–orbicularis muscle advancement techniques in the management of severe congenital blepharoptosis and to create clarity for further studies with longer follow-ups. Herein, the authors describe the surgical steps and highlight the surgical results of some of their patients in both the adult and pediatric age groups after obtaining appropriate informed consent from the patients/guardians [Figs. 5–7].

Figure 5.

(a) A middle-aged patient presented with bilateral ptosis (LPS- Levator palpebreae superioris, OD (Right eye), OS (Left eye)) action OD <7 mm, OS <4 mm, along with good frontalis action. (b) On-table correction with frontalis muscle flap advancement performed for OS and levator palpebrae superioris resection performed for OD, which resulted in symmetric upper lid position. (c, d) One month postsurgery image showing symmetrical eyelid height and absence of lagophthalmos

Figure 7.

(a, b) Lid crease marking and incision with exposure of the tarsus. (c, d) Dissection done in the sub-orbicularis preseptal plane superiorly up to the supraorbital margin to expose arcus marginalis. (e, f) Dissection carried out superior to arcus marginalis up to 2 cm above the eyebrow in the subcutaneous forehead region for fashioning the frontalis flap. (g, h) The frontalis muscle flap mobilized and further advanced to be secured to the upper one-third of the tarsal plate with two fixation sutures using 5-0 polypropylene. (i) On-table correction with the eyelid margin kept at the level of superior limbus

Figure 6.

(a) A pediatric case with unilateral congenital ptosis and poor LPS function. (b, c) Immediate post-op correction with frontalis muscle flap advancement, showing normal eye closure without any lagophthalmos. (d) Another pediatric case with unilateral congenital ptosis along with poor LPS action. (e, f) One month postsurgery figures showing adequate correction with very minimal lagophthalmos

Conclusion

After reviewing all the techniques, we found that each technique demonstrates its unique advantages and shortcomings, indicating that there is no universally superior or correct approach that addresses severe blepharoptosis. A prerequisite for achieving satisfactory results lies in possessing appropriate knowledge of current surgical trends and understanding the patient's expectations. Adopting a standardization may help facilitate more comprehensive review studies in future and provide new insights regarding the long-term outcomes of surgical correction of severe blepharoptosis. Despite the extensive use of FM flap advancement for correcting severe blepharoptosis, a consensus on the most suitable procedure has not been reached due to the lack of long-term follow-up. Further studies, encompassing long-term results and incorporating current trends, are essential for establishing more robust conclusions in the field.

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Conflicts of interest

There are no conflicts of interest.