Anatomical description of the upper tarsal plate for reconstruction

Thickness of the Medial Pretarsal Adipose Tissue in the Upper Eyelid among the Japanese Population

PURPOSE

To investigate the medial pretarsal adipose tissue thickness of the upper eyelid in the Japanese population.

METHODS

Sixty-two whole upper eyelids were harvested from 35 Japanese cadavers and fixed in paraffin. The samples were cut into 5 µm sagittal microsections and stained with hematoxylin and eosin, as well as Masson's trichrome. Data obtained from images and measurements were taken with Aperio ScanScope and ImageScope software and underwent statistical analysis.

RESULTS

The samples were divided into 3 shapes sagittal cross-sections of the eyelid (triangular, rectangular, and flat) corresponding to the shape of the medial pretarsal adipose tissue. Type I (triangular shape, 48.4%) had a ratio of fat thickness at 1⁄2 tarsal height to peak fat thickness of <0.9, and type IIa (rectangular shape, 30.6%) and IIb (flat shape, 21.0%) had pretarsal adipose tissue thickness to tarsal height ratio of ≥0.2 and <0.2, respectively. The mean values of tarsal thickness at 1⁄2 tarsal height were 1021 µm for the type I group, 1100 µm for the type IIa group, and 764.4 µm for the type IIb group ( p = 0.01). The mean values of fat thickness at 1⁄2 tarsal height were 410.6 µm for the type I group, 303.3 µm for the type IIa group, and 242.6 µm for the type IIb group ( p = 0.26).

CONCLUSIONS

The thickness of the medial pretarsal adipose tissue was different according to the shape of the sagittal cross-section of the eyelid. Awareness of the medial pretarsal adipose tissue thickness contributes to effective suture placement and safe suture depth during blepharoptosis surgery.

Bioengineering autologous cartilage grafts for functional posterior lamellar eyelid reconstruction: A preliminary study in rabbits

The reconstruction of posterior lamellar eyelid defects remains a significant challenge in clinical practice due to anatomical complexity, specialized function, and aesthetic concerns. The ideal substitute for the posterior lamellar should replicate the native tarsoconjunctival tissue, providing both mechanical support for the eyelids and a smooth surface for the globe after implantation. In this study, we present an innovative approach utilizing tissue-engineered cartilage (TEC) grafts generated from rabbit auricular chondrocytes and a commercialized type I collagen sponge to reconstruct critical-sized posterior lamellar defects in rabbits. The TEC grafts demonstrated remarkable mechanical strength and maintained a stable cartilaginous phenotype both in vitro and at 6 months post-implantation in immunodeficient mice. When employed as autografts to reconstruct tarsal plate defects in rabbits' upper eyelids, these TEC grafts successfully restored normal eyelid morphology, facilitated smooth eyelid movement, and preserved the histological structure of the conjunctival epithelium. When applied in bilayered tarsoconjunctival defect reconstruction, these TEC grafts not only maintained the normal contour of the upper eyelid but also supported conjunctival epithelial cell migration and growth from the defect margin towards the centre. These findings highlight that auricular chondrocyte-based TEC grafts hold great promise as potential candidates for clinical posterior lamellar reconstruction. STATEMENT OF SIGNIFICANCE: The complex structure and function of the posterior lamellar eyelid continue to be significant challenges for clinical reconstructive surgeries. In this study, we utilized autologous auricular chondrocyte-based TEC grafts for posterior lamellar eyelid reconstruction in a preclinical rabbit model. The TEC grafts exhibited native cartilaginous histomorphology and comparable mechanical strength to those of the native human tarsal plate. In rabbit models with either tarsal plate defects alone or bilayered tarsoconjunctival defects, TEC grafts successfully restored the normal eyelid contour and movement, as well as supported preservation and growth of conjunctival epithelium. This is the first study to demonstrate autologous TEC grafts can be employed for repairing tarsal plate defects, thereby offering an alternative therapeutic approach for treating posterior lamellar defects in clinic settings.

A new algorithm for the transconjunctival correction of moderate to severe upper eyelid ptosis in adults

A posterior approach is recommended for the correction of mild to moderate upper eyelid ptosis in adults. The aim of this study is to propose a new algorithm that helps to predict outcomes in the transconjunctival correction of moderate to severe blepharoptosis. This study included adult patients with moderate to severe upper eyelid ptosis treated between 2019 and 2021. Patients meeting inclusion criteria underwent ptosis correction through a posterior approach using an algorithm: 4 mm Mueller's muscle transconjunctival resection to correct 1 mm ptosis (depending on a test with 10% phenylephrine: 3-12 mm) ± tarsal plate resection: 1 mm for every 1 mm of residual ptosis after phenylephrine test, but leaving a minimum of 4 mm upper tarsus intact. Outcomes were ovserved within at least 6-months. Outcomes were assessed based on pre- and postoperative MRD1 changes, inter-eyelid height symmetry, cosmetic effect, and complications. Outcomes of 118 procedures in 81 patients (average age 69, range: 47-87) were analyzed. MRD1 changes were statistically significant, from 0.2 ± 1.6 mm before to 4.1 ± 1 mm after surgery. The function of the levator palpebrae superioris muscle was 10.2 ± 3.4 (range 5-17) mm. Upper eyelid lifted by an average of 1.8 ± 0.7 (range 0-3) mm after the instillation of 10% phenylephrine eyedrops. An average of 8.5 ± 0.8 (range 8-10) mm of conjunctiva and Mueller's muscle and 2.2 ± 0.9 (range 1-5) mm of the tarsal plate were resected during the procedure. Inter-eyelid height symmetry within 1 mm was achieved in 95% of outcomes. The algorithm introduced in this study appears to be useful to achieve repeatable satisfactory outcomes in the transconjunctival correction of moderate to severe upper eyelid ptosis in adults with at least "fair" levator function.

Polymers and Biomaterials for Posterior Lamella of the Eyelid and the Lacrimal System

The application of biopolymers in the reconstruction of the posterior lamella of the eyelid and the lacrimal system marks a significant fusion of biomaterial science with clinical advancements. This review assimilates research spanning 2015 to 2023 to provide a detailed examination of the role of biopolymers in reconstructing the posterior lamella of the eyelid and the lacrimal system. It covers the anatomy and pathophysiology of eyelid structures, the challenges of reconstruction, and the nuances of surgical intervention. This article progresses to evaluate the current gold standards, alternative options, and the desirable properties of biopolymers used in these intricate procedures. It underscores the advancements in the field, from decellularized grafts and acellular matrices to innovative natural and synthetic polymers, and explores their applications in lacrimal gland tissue engineering, including the promise of 3D bioprinting technologies. This review highlights the importance of multidisciplinary collaboration between material scientists and clinicians in enhancing surgical outcomes and patient quality of life, emphasizing that such cooperation is pivotal for translating benchtop research into bedside applications. This collaborative effort is vital for restoring aesthetics and functionality for patients afflicted with disfiguring eyelid diseases, ultimately aiming to bridge the gap between innovative materials and their clinical translation.

Ultrasound-based histological differences of pretarsal fat fascia before and after double eyelid blepharoplasty with the orbital septum method

OBJECTIVE

To observe the changes of pretarsal fat fascia histological structure after double eyelid blepharoplasty with the orbital septum method.

METHODS

From December 2019 to February 2022, the patients with congenital single eyelid who underwent double eyelid blepharoplasty with the orbital septum method at the Plastic and cosmetic surgery department of Hunan provincial people's Hospital and the same number of congenital double eyelid volunteers. Then divided into three groups: preoperative eyelid ultrasound images in Group A, postoperative eyelid ultrasound images in Group B, and congenital double eyelid volunteers in Group C. To study the histological differences of pretarsal fat fascia before and after double eyelid blepharoplasty with the orbital septum method and congenital double eyelid by ultrasound.

RESULTS

Ninety-eight patients who underwent double eyelid blepharoplasty with the orbital septum method met the inclusion criteria. All 98 patients aged 22.88 ± 3.00 years, including 7 males and 91 females, followed up for 6-12 months. Included 98 volunteers with congenital double eyelid, aged 23.58 ± 2.59 years, including 49 males and 49 females. Ultrasound showed that the pretarsal fat fascia was divided into two layers. The dense layer adhered closely to the surface of the tarsus with no statistically significant differences. There was a statistically significant difference in the thickness of the pretarsal loose fat fascia layer between Group A and B. The points a b c in Group A were significantly thicker than those in Group B and C, and there was no significant difference between Group B and C. Postoperative evaluation: 83 cases were satisfied, 11 cases were basically satisfied and 4 cases were unsatisfied.

CONCLUSION

After double eyelid blepharoplasty using orbital septum, the histological structure of pretarsal fat fascia is similar to that of congenital double eyelid, suggesting that double eyelid blepharoplasty with the orbital septum method can change the structure of pretarsal fat fascia and make it similar to congenital double eyelid, which is one of the anatomical bases for its good clinical effect.

Anatomical and Histological Study of the Upper Tarsus in Asian

OBJECTIVE

The aim of this study was to observe and analyze the anatomical and histological characteristics of the upper tarsus in Asian.

METHODS

A total of 15 Asians (14 adults, 1 child) were used. The sagittal sections with thickness of 3 μm in the middle of the upper eyelid were prepared and stained with hematoxylin-eosin, Masson trichrome and anti-smooth muscle actin antibody staining, and then were observed and photographed under light microscopy.

RESULTS

On the sagittal section, the upper end of the tarsus was connected with the Müller muscle and the part of the posterior layer of the levator aponeurosis; the lower end was the inflated part of the palpebral margin; the superficial surface was connected with the pretarsal fascia; and the deep surface was connected with Müller muscle aponeurosis and palpebral conjunctiva. Histologically, the tarsus was similar to the structure between dense fibrous connective tissue and cartilage, and its main structures include meibomian glands and its ducts, accessory lacrimal glands, glands of Moll, glands of Zeis, eyelash hair follicles, Riolan muscle, blood vessels, and collagen fibers. Through the observation of the tarsus of a child, compared with the adult specimen, the meibomian gland tissue was more abundant; the collagen fibers density was significantly lower and arranged orderly; the blood vessel density was significantly higher; α-SMA positive smooth muscle cells could be seen in the upper end of the tarsus and its superficial and deep surfaces.

CONCLUSIONS

In this study, the internal and adjacent anatomical structures of the upper tarsus in Asians were observed under a microscope, and according to the histological characteristics, the tarsus was divided into 3 parts and 3 types. Through the preliminary analysis, the tarsus was likely to show different histological characteristics in different individuals and age groups of Asians. There was a certain correlation between the degree of meibomian gland atrophy, the degree of collagen fibrosis and the density of blood vessel in the tarsus.

Surgical Strategies for Eyelid Defect Reconstruction: A Review on Principles and Techniques

Reconstruction of eyelid defects, especially the posterior lamella, remains challenging because of its anatomical complexity, functional considerations, and aesthetic concerns. The goals of eyelid reconstruction include restoring eyelid structure and function and achieving an aesthetically acceptable appearance. An in-depth understanding of the complex eyelid anatomy and several reconstructive principles are mandatory to achieve these goals. Currently, there are multiple surgical treatment options for eyelid reconstruction, including different flaps, grafts, and combinations of them. This comprehensive review outlines the principles of reconstruction and discusses the indications, advantages, and disadvantages of currently available surgical techniques. We also propose our clinical thinking for solving specific clinical questions in eyelid reconstruction and offer perspectives on new potential methodologies in the future.

Anatomic Trends and Directions in Periorbital Aesthetic Surgery

The anatomy of the eyelids and periorbital region is delicate. The individual anatomic variations determine each person's eyelid appearance and function. It is essential that every surgeon that evaluates and treats the aesthetic conditions of patients desiring periorbital enhancement understands the association of anatomy and diagnosis. Each periorbital aesthetic diagnosis has an anatomic basis, and knowledge of the applied anatomy allows a targeted treatment plan. This article outlines the layered anatomy with its clinical significance for the eyelids and periorbital region. Specific examples are used to illustrate the applied anatomy. A contemporary treatment plan for each anatomic problem is given.