Brow and Eyelid Rejuvenation: Trends from the 100 Most Cited Articles over 30 Years

Background and Objective: Various periorbital rejuvenation techniques have been introduced over the last 3 decades. This study highlights important milestones in the evolution of periorbital rejuvenation surgery by identifying the 100 most-cited articles in this field. Material and Methods: The Web of Science citation index was used to identify the 100 most-cited articles concerning periorbital rejuvenation. Articles published in English from January 1989–April 2020 describing periorbital rejuvenation-related surgical techniques, facial aging, and anatomy were included. The terms “lower blepharoplasty”, “upper blepharoplasty”, “browlift”, “browplasty”, “endobrow lift”, “endoscopic brow”, “Foreheadplasty”, “lower eyelid anatomy”, “upper eyelid anatomy”, “forehead lift”, “eyelid rejuvenation”, “canthopexy”, “canthoplasty”, “eyelid fat pad”, “orbital fat pad”, “tear trough”, and “eyelid bags” were entered into the citation search. Web of Science Core Collection was the database used for the search. A manual review of the initial 159 studies was performed. Articles describing reconstructive or non-invasive techniques, injectable fillers, lasers, and neurotoxins were excluded. Of the 100 most-cited articles, the publication year, specialty journal, the corresponding author’s primary specialty, the focus of the article, the corresponding author’s country of residence, the type of study, and the level of evidence were analyzed. Results: The mean number of citations per article was 75 ± 42. There were more articles published from 1989–1999 (n = 53) than later decades. Most articles originated from the USA (n = 82) and were published in plastic surgery journals (n = 81). Plastic surgery was the primary specialty of the corresponding authors (n = 71), followed by oculoplastic surgery (n = 22). Most articles (n = 69) reported on surgical techniques. Of the clinical studies (n = 69), 45 (79%) provided level IV evidence. Conclusions: Of the 100 most-cited studies on periorbital rejuvenation, studies focusing on periorbital anatomy, aging, and surgical techniques comprised the most-cited publications. An anatomically based approach accounting for age-related changes in the periorbital structures is paramount in the field of contemporary periorbital rejuvenation.


Introduction
The human face is composed of layers that play a role in facial appearance and aging. These layers are arranged in five lamellar components that are clearly defined in the scalp and range from superficial to deep, as follows: skin, subcutaneous tissue, the musculoaponeurotic layer (superficial musculoaponeurotic system-SMAS), loose areolar tissue, and the deep fascia or periosteum. Facial rejuvenation is based on the manipulation and redraping of these tissue layers as well as specific anatomic attachments including ligaments, adhesions, and septa.
Rejuvenation, a word originating from the Latin words "re" and "juvenis", meaning "young again", has always been a historic interest in various cultures and civilizations.

Results
The initial search was limited to 159 articles. Then, the abstracts of the most-cited 159 articles were individually reviewed. The 100 most-cited articles on periorbital rejuvenation are listed in this study ( Table 1). The 100 most-cited articles were published between 1989 and 2020, spanning a 30-year period. The mean number of citations per article was 75 (standard deviation-SD: 42). There was a higher prevalence of articles published between 1989 and 1999 (n = 53) than later decades ( Figure 2). Most articles (81%) were published in plastic surgery journals, of which 78% were published in the Plastic and Reconstructive Surgery Journal (n = 63) and originated from the United States (n = 82, 82%) (Figures 3 and 4). Plastic and reconstructive surgery was the primary specialty of the corresponding authors in 71% of articles (n = 71), followed by oculoplastic surgery (n = 22) ( Figure 5).

Results
The initial search was limited to 159 articles. Then, the abstracts of the most-cited 159 articles were individually reviewed. The 100 most-cited articles on periorbital rejuvenation are listed in this study ( Table 1). The 100 most-cited articles were published between 1989 and 2020, spanning a 30-year period. The mean number of citations per article was 75 (standard deviation-SD: 42). There was a higher prevalence of articles published between 1989 and 1999 (n = 53) than later decades ( Figure 2). Most articles (81%) were published in plastic surgery journals, of which 78% were published in the Plastic and Reconstructive Surgery Journal (n = 63) and originated from the United States (n = 82, 82%) (Figures 3 and 4). Plastic and reconstructive surgery was the primary specialty of the corresponding authors in 71% of articles (n = 71), followed by oculoplastic surgery (n = 22) ( Figure 5).

Results
The initial search was limited to 159 articles. Then, the abstracts of the most-cited 159 articles were individually reviewed. The 100 most-cited articles on periorbital rejuvenation are listed in this study ( Table 1). The 100 most-cited articles were published between 1989 and 2020, spanning a 30-year period. The mean number of citations per article was 75 (standard deviation-SD: 42). There was a higher prevalence of articles published between 1989 and 1999 (n = 53) than later decades ( Figure 2). Most articles (81%) were published in plastic surgery journals, of which 78% were published in the Plastic and Reconstructive Surgery Journal (n = 63) and originated from the United States (n = 82, 82%) (Figures 3 and 4). Plastic and reconstructive surgery was the primary specialty of the corresponding authors in 71% of articles (n = 71), followed by oculoplastic surgery (n = 22) ( Figure 5).     Of the 100 articles, 69 described surgical techniques, followed by anatomy (n = 22) and aging (n = 9). Clinical studies encompassed 57% of the top 100 most-cited articles, followed by review articles (n = 29) and basic science studies (n = 14). Clinical articles were classified according to their Level of Evidence. None of the studies provided level I evidence. Two studies [18] qualified as providing level II evidence, and two articles [19,20]    Of the 100 articles, 69 described surgical techniques, followed by anatomy (n = 22) and aging (n = 9). Clinical studies encompassed 57% of the top 100 most-cited articles, followed by review articles (n = 29) and basic science studies (n = 14). Clinical articles were classified according to their Level of Evidence. None of the studies provided level I evidence. Two studies [18] qualified as providing level II evidence, and two articles [19,20]    Of the 100 articles, 69 described surgical techniques, followed by anatomy (n = 22) and aging (n = 9). Clinical studies encompassed 57% of the top 100 most-cited articles, followed by review articles (n = 29) and basic science studies (n = 14). Clinical articles were classified according to their Level of Evidence. None of the studies provided level I evidence. Two studies [18] qualified as providing level II evidence, and two articles [19,20]  Of the 100 articles, 69 described surgical techniques, followed by anatomy (n = 22) and aging (n = 9). Clinical studies encompassed 57% of the top 100 most-cited articles, followed by review articles (n = 29) and basic science studies (n = 14). Clinical articles were classified according to their Level of Evidence. None of the studies provided level I evidence. Two studies [18] qualified as providing level II evidence, and two articles [19,20] provided level III evidence. Of the remaining 57 most-cited clinical studies, 45 studies (79%) provided level IV and 8 provided level V evidence (14%) ( Figure 6). provided level III evidence. Of the remaining 57 most-cited clinical studies, 45 studies (79%) provided level IV and 8 provided level V evidence (14%) ( Figure 6).   A timeline of the articles was created to better visualize the evolution of periorbital rejuvenation surgery techniques (Figures 7-12). The most clinically relevant articles within each 5-year period are featured in the timeline.  (Figure 6). A timeline of the articles was created to better visualize the evolution of periorbital rejuvenation surgery techniques (Figures 7-12). The most clinically relevant articles within each 5-year period are featured in the timeline.

Discussion
Facial aging is a result of changes in the five lamellar structures of the face and the underlying facial bony skeleton. Throughout life, there is apparent descent, atrophy, or hypertrophy of certain compartments within the face that make it appear more aged [23,34,117]. Aging is manifested in the lateral translation of the orbits, glabellar protrusion, the expansion of the supraorbital ridges, the deepening and lateral expansion of the cheeks, the three-dimensional enlargement of the nose, and an increase in chin prominence, as described by Enlow [118] and Mendelson and Wong [119]. The interplay between the bony skeleton, supporting ligaments, fat compartments, and facial mimetic muscles is influenced by physiological, genetic, and environmental factors [120]. These factors involve bone remodeling and functional effects of the surrounding muscles' action (i.e., the effects of chronic orbicularis oculi contraction on lateral brow position). The youthful eye is characterized by an almond-shaped palpebral fissure with a slight upward slope from the medial to lateral canthus. Concerning periorbital aging, Lambros [23,121] noted "the eyes seem to get smaller as one ages, the entire lid aperture gets smaller because the lower lid rises, the upper lid falls, the lid gets shorter from the side, and the fat pads enlarge" [26,122]. Therefore, surgeons treating periorbital aging should consider all of these structures and the accompanying changes to achieve optimal rejuvenation. The improvement in the anatomical understanding of periorbital structures over the last 3 decades has contributed to a better understanding of the aging process and has enhanced the surgical strategies used to achieve more youthful and attractive eyes [10,21,47,55,117,[123][124][125][126].

Evolution of Periorbital Rejuvenation over the Last 3 Decades
Periorbital rejuvenation has evolved to include a multitude of approaches to addressing aging-related changes of the orbit such as skin excision, SMAS re-draping, orbicularis oculi muscle repositioning, fat pad reduction or transposition, the release of the orbicularisretaining ligament (ORL), and micro/nano fat grafting [26,31,43,47,127]. A comprehensive approach to upper eyelid rejuvenation includes the brow and forehead. Similarly, for lower lid rejuvenation, the midface is involved [128].
In 1989, Cook et al. [107] reported their experience in extending the indications of the midforehead brow lift beyond functional lifts in men with receding hairlines to include aesthetic brow lifting in women. The authors described their surgical technique, which included staggering midforehead elliptical excisions, the undermining of the inferior forehead skin, and the placement of suspension sutures in the mid and lateral brow. Good results among 52 female patients were reported. This study was ranked 90th among the top 100 most-cited articles. In the same year, Connell et al. [83] reported their approach to forehead lifting and emphasized proper diagnosis and planning with respect to forehead rejuvenation by considering the degree of brow ptosis associated with the upper eyelid skin's laxity. They advocated for the proper placement of forehead lift incisions, selective frontalis muscle thinning, and procerus and corrugator supercilii debulking to improve medial brow and upper nasal aesthetics. In 1994, Isse [25] described his endoscopic "endoforehead lift" technique in a total of 61 cases, and his article became the 5th most-cited article. The author reported that he was able to achieve satisfactory cosmetic results with minimal and fewer complications when compared to the conventional coronal incision forehead lift. That same year, Ramirez [28] reviewed different endoscopic forehead and facelift options (the 10th most-cited article). These included endoscopic corrugator-procerus muscle resection without a lift, a browlift with slit incisions, a standard facelift combined with endoscopic corrugator-procerus laser ablation, an endoscopic subperiosteal browlift with precapillary skin excision and the preservation of the scalp's innervation, an endoscopic browlift combined with an excisional subperiosteal or composite facelift, and an endoscopic full facelift. In 1996, Knize [63] described his limited-incision forehead lift technique to achieve eyebrow elevation for an enhanced upper blepharoplasty. In this technique, the author used temporal scalp incisions of only 4.5 to 5 cm in length while also performing a transpalpebral resection of the corrugator supercilii muscles and a transection of the procerus muscle. This created a more acceptable aesthetic result compared to the coronal scalp incision, thus minimizing the risk of injuring the supraorbital nerve branches and being comparable to the endoscopic techniques in this regard. This article has become the 45th most-cited article related to periorbital rejuvenation. By the early 2000s, the endoscopic brow/forehead lift had gained significant popularity [19,35,75,76]. In 2004, Jones and Grover [76] reported their experience with 538 endoscopic brow lift cases and compared the outcomes of two different fixation techniques: fibrin glue versus polydioxanone sutures tied through bone tunnels. The authors found that the endoscopic brow lift provided a significant increase in the pupil to brow height while fixation with polydioxanone sutures tied through bone tunnels produced a significantly more stable result than fibrin glue.
In 1995, Hamra [22] described arcus marginalis release and the advancement of lower eyelid fat as an alternative to its excision to avoid the resulting hollow contour deformity, which is now synonymous with "the operated appearance". In his study of 152 cases, which is the second most-cited article, Hamra reported satisfactory results with a minimal rate of complication. In 2000, Goldberg [31] described the transposition of orbital fat pedicles into a subperiosteal pocket through a transconjunctival approach. That same year, Hester et al. [26] published a retrospective review of 757 patients who underwent direct trans-lower eyelid blepharoplasty to correct midfacial aging. In this sixth most-cited paper (n = 128), the authors described a sub-periosteal approach to the lower eyelid and midface as opposed to traditional lateral vector techniques. Two years later, Muzaffar et al. [16] described the ORL, which became an important structure to release while performing orbicularis oculi suspension (re-draping) and canthopexy. In 2012, Mendelson et al. [55] described the tear trough ligament, a true osteocutaneous ligament, and its contribution to tear trough (nasojugal groove) deformity due to the ligament's tethering effect. The authors proposed a complete release of this ligament, especially in patients with moderate to severe deformity.
As a topic of continued debate, it is also worth discussing the popularity and preference for the transcutaneous and transconjunctival approaches to lower blepharoplasty. Both techniques have been represented in the top 100 cited article list but there was a greater number of articles advocating the transconjunctival approach (n = 5 versus n = 1). In their study in 2008, Codner et al. [33] reviewed their experience with primary lower transcutaneous blepharoplasty via a subciliary skin incision in 264 patients over 10 years, which was the 15th most-cited article included in our study. The authors reported that nine (3.5%) patients had eyelid malposition that required operative correction while one (0.4%) patient had an orbital hematoma. They concluded that lateral canthal support should be considered a routine component of lower transcutaneous blepharoplasty. In 2010, Pacella et al. [91] reviewed the anatomy, indications, and outcomes of lower transconjunctival blepharoplasty in their article (the 74th most-cited article). In their senior author's personal experience (Dr. Foad Nahai) with 300 lower lid blepharoplasties between 1992 and 1995, the complication rate for the transconjunctival group was 5% (6 out of 120 patients) versus 13% (24 out of 180 patients) for the transcutaneous group. In the transconjunctival group, there was no lid retraction, which was a complication experienced by 3.3% (n = 6) in the transcutaneous group. The authors concluded that the transconjunctival lower blepharoplasty was a safe and effective procedure for periorbital rejuvenation. They also noted that in cases of excessive skin laxity, a transcutaneous approach compared to the transconjunctival blepharoplasty may achieve better results with the addition of lateral canthoplasty and/or lateral canthal anchoring procedure to minimize the risk of lower-lid malposition. The importance of the proper assessment and diagnosis of factors that may contribute to lower-lid malposition was highlighted by Jelks et al. [40,87,129]. As such, lateral canthoplasty for managing potential lower-lid malposition after blepharoplasty has become routine practice in contemporary lower blepharoplasty.
As emphasized in this article, the studies on facial aging and anatomy have impacted periorbital rejuvenation strategies significantly. In 1992, Hykin and Bron [18] studied the age-related changes in the eyelid margin in 80 subjects, and this article has become the ninth most-cited article (n = 121). In the study, it was reported that with aging, the lid margin became thicker after childhood, lid margin vascularity and cutaneous hyperkeratinization increased in both lids, and telangiectasia increased in the lower lid. The description of suborbicularis orbital fat (SOOF) by Aiache and Ramirez [47] in 1995 also influenced the correction strategies for deformities in the lower eyelids, just as retroorbicularis oculus fat (ROOF) influenced the upper eyelid rejuvenation technique pioneered by Owsley [130] and May [77]. In the following year, Knize's [24] anatomical study on 20 (40 half-head) fresh cadavers was published and has since become the 4th most-cited article (n = 175). The author reported that eyebrow ptosis occurs more profoundly on the brow's lateral segment, and this was promoted by the changes in the galeal fat pad, the preseptal fat pad, and the subgaleal fat pad glide plane space. In addition, he described the impact of the dynamic interactions between the frontalis muscle's resting tone and gravity, and the corrugator supercilii and the lateral orbicularis oculi muscles' hyperactivity on lateral eyebrow position. In 2007, the cadaveric study by Rohrich and Pessa [21] described the subcutaneous fat pad compartments, constituting another important contribution to a more in-depth understanding of facial anatomy. This is the most-cited article of the articles related to periorbital rejuvenation within the last 3 decades. Another important publication that impacted rejuvenation strategies was Lambros' [23] observational study published in the same year, which has become the third most-cited article (n = 204). He compared the 10to 50-year-old photographs of 130 subjects with their recently taken follow-up photographs to assess the effects of aging on the face. The interesting findings from this study included the lateral movement of the arc peak, the apparent decrease in eye size, and the relative stability of the position of the lid-cheek junction over time.
Although not the subject of this article, injectables play an important role in modern periorbital rejuvenation. In 1981, bovine collagen became the first agent that was approved for cosmetic injection by the FDA [131]. The introduction of hyaluronic acid in 2003 initiated a new era for non-surgical peri-orbital and facial rejuvenation. According to statistics released by the American Society of Plastic Surgeons (ASPS), 79.5% of 2,676,970 soft tissue filler procedures performed in 2018 used hyaluronic acid fillers [132]. These fillers are currently used widely by a multitude of practitioners across multiple specialties with satisfactory aesthetic results; however, their relatively short-lived effect is the main drawback compared to these surgical techniques. Another important factor, which is not accounted for in the cited articles but impacts eyelid and brow rejuvenation trends nonetheless, is society's evolving perception of beauty in each era and the influence of pop culture and social media on such trends. What Westmore postulated as the ideal female brow position in the 1980s has now been replaced by the more lateral position of the brow's peak closer to the lateral canthus [133].
As we have summarized, the current surgical techniques of periorbital rejuvenation have evolved as our understanding of facial has anatomy progressed. More conservative fat and muscle excisions with which to prevent the "operated" appearance and post-operative complications dominate our current approaches to peri-orbital rejuvenation [49]. Twentyone percent of the one hundred most-cited articles within the last 31 years focused on periorbital anatomy and its clinical relevance to periorbital aesthetic surgery. This list of articles offers a comprehensive compilation of studies to readers interested in advancing their knowledge of periorbital rejuvenation.
This study is not without limitations. There is potential for citation bias contributing to the citation rankings in this study. Authors may tend to select references that support their conclusions [134]. Self-citation can also play a role in citation bias [135]. Furthermore, the number of citations in the last decade remained the lowest among the 3 decades reported (Figure 2). This does not mean that these articles were of lesser importance or had a lower impact on practice changes; rather, it reflects the time factor required for these articles to be cited. Lastly, as more articles on the same topic are published, the authors have a larger pool of references from which to cite, thus generating a dilution effect concerning the articles published in later years compared to the older citations.

Current Approaches to Brow and Eyelid Rejuvenation
There are three surgical approaches to browlift: trans-blepharoplasty brow lift, direct brow lift, and trans-forehead brow/forehead lift. The latter two have the longest-lasting effect [136]. Direct browlifts are most often used in patients with brow ptosis due to a nerve injury, such as those with Bell's Palsy, but they are also good options for men with a receded hairline and women who desire only a lateral brow lift [137]. It is the most predictable method for browlift, as the incision is placed just above the superior end of the brow or along a rhytid near the brow. In addition, the degree of lift one can expect post-operatively is proportional to the amount of tissue removed [138]. However, scars are a major concern with respect to direct brow lift and there is currently a move towards more minimally invasive approaches [136,139,140].
The endoscopic approach is another technique that was popular in the last 3 decades and may still be practiced by some surgeons. However, other techniques, such as the gliding brow lift, are gaining more popularity. The gliding brow lift can elevate the brow without raising the forehead's height [141]. One advantage of this technique is that it requires only two 3 mm scalp incisions in the frontotemporal area. The surgeon undermines directly above the frontalis and galea down to 1 cm below the eyebrows. A plane of subcutaneous tissue is elevated and then sutured to the frontalis and galea via a hemostatic net to maintain brow elevation. As with any new technique, there are early, middle, and late adopters, resulting in a variable lag time between the introduction of a surgical technique and publications supporting its safety or efficacy. Figure 13 demonstrates a summary of the types of incisions used in the different types of browlift.
brow or along a rhytid near the brow. In addition, the degree of lift one can expect postoperatively is proportional to the amount of tissue removed [138]. However, scars are a major concern with respect to direct brow lift and there is currently a move towards more minimally invasive approaches [136,139,140].
The endoscopic approach is another technique that was popular in the last 3 decades and may still be practiced by some surgeons. However, other techniques, such as the gliding brow lift, are gaining more popularity. The gliding brow lift can elevate the brow without raising the forehead's height [141]. One advantage of this technique is that it requires only two 3 mm scalp incisions in the frontotemporal area. The surgeon undermines directly above the frontalis and galea down to 1 cm below the eyebrows. A plane of subcutaneous tissue is elevated and then sutured to the frontalis and galea via a hemostatic net to maintain brow elevation. As with any new technique, there are early, middle, and late adopters, resulting in a variable lag time between the introduction of a surgical technique and publications supporting its safety or efficacy. Figure 13 demonstrates a summary of the types of incisions used in the different types of browlift. Upper blepharoplasty is often combined with browlift surgery. Current methods of upper eyelid blepharoplasty are more conservative and refrain from the removal of the orbicularis oculi and excessive orbital fat resection to prevent a hollowed-out appearance. Modern lower blepharoplasty has shifted from fat resection to volume redistribution or augmentation through fat transposition or micro and nano fat grafting [142,143]. While these techniques may be more popular in current practice, citations supporting their use may underreport their popularity.
There are two main surgical approaches to lower blepharoplasty: a transcutaneous and transconjunctival approach. Based on questionnaires sent out to members of the American Society of Ophthalmic Plastic and Reconstructive Surgery who perform blepharoplasty, more surgeons use the transconjunctival approach [144]. Some advantages of the transconjunctival approach include the absence of scarring following surgery, decreased recurrence of lower-lid bulging, and the avoidance of complications such as vertical lid shortening [145]. Fat repositioning and canthal suspension were frequently performed along with lower blepharoplasty [144]. Regarding fat repositioning, the planes of dissection are subperiosteal, supraperiosteal, and intra-SOOF. The complication rates in these three planes are low when performed by experienced surgeons, but there is a high Upper blepharoplasty is often combined with browlift surgery. Current methods of upper eyelid blepharoplasty are more conservative and refrain from the removal of the orbicularis oculi and excessive orbital fat resection to prevent a hollowed-out appearance. Modern lower blepharoplasty has shifted from fat resection to volume redistribution or augmentation through fat transposition or micro and nano fat grafting [142,143]. While these techniques may be more popular in current practice, citations supporting their use may underreport their popularity.
There are two main surgical approaches to lower blepharoplasty: a transcutaneous and transconjunctival approach. Based on questionnaires sent out to members of the American Society of Ophthalmic Plastic and Reconstructive Surgery who perform blepharoplasty, more surgeons use the transconjunctival approach [144]. Some advantages of the transconjunctival approach include the absence of scarring following surgery, decreased recurrence of lower-lid bulging, and the avoidance of complications such as vertical lid shortening [145]. Fat repositioning and canthal suspension were frequently performed along with lower blepharoplasty [144]. Regarding fat repositioning, the planes of dissection are subperiosteal, supraperiosteal, and intra-SOOF. The complication rates in these three planes are low when performed by experienced surgeons, but there is a high learning curve. Dissecting the supraperiosteal plane runs the risk of injuring the blood vessels, while using the subperiosteal plane does not allow for the release of the ORL, tear trough, and lid-cheek junction. To address this, a new approach using the midcheek spaces for orbital fat repositioning has been proposed, offering improvements in terms of lower-lid fat and herniated orbital fat and a decreased prominence of the lid-cheek junction [146]. Additionally, combining lower eyelid surgery with midface rejuvenation surgery can result in greater cosmetic outcomes, depending on the degree of lower eyelid skin laxity, midface descent, and midface volume [147].
While women accounted for 85% of blepharoplasty procedures in the United States, a transconjunctival approach is preferred in men undergoing lower blepharoplasty, as their primary concern was found to be the formation of the deep palpebromalar groove and tear-trough deformity [148,149]. A transconjunctival approach permits easy access to the periorbital fat compartments for fat excision.

Conclusions
Over the last 3 decades, periorbital rejuvenation techniques have evolved in tandem with our knowledge of periorbital anatomy and aging. Studies focusing on periorbital anatomy, aging, and surgical techniques were the most-cited publications. An anatomically based approach that is customized for each patient and accounts for age-related changes in the periorbital structures is paramount in contemporary periorbital rejuvenation.

Conflicts of Interest:
The authors declare no conflict of interest.
Financial Disclosure: None of the authors have financial interests in any of the products, devices, or drugs mentioned in this manuscript.