Ultrasound biomicroscopic features of the normal lower eyelid

Lower Eyelid Surgical Anatomy and the Implications for Blepharoplasty Surgery: A Systematic Review of Anatomic Studies in the Literature

Lower eyelid blepharoplasty is a procedure to address issues arising from age-related anatomic changes of the lower eyelid. These include excess skin, fat herniation, tear trough hollowing, and midface descent. Unlike the well-defined structures of the upper eyelid, the lower eyelid's anatomy, including the retractors and surrounding ligaments, is less distinct and understudied. In addition, lower eyelid blepharoplasty has an unfavorable complication profile compared with that of the upper eyelid. This review examines relevant studies on lower eyelid anatomy, focusing on age-related structural changes and the variability of key structures involved in blepharoplasty surgery to minimize the risk of complications and achieve desirable outcomes. A literature search for relevant publications on the topic was performed through Medline and PubMed, with the appropriate data extracted, identifying 54 relevant studies. These studies demonstrate how degenerative changes to the supporting structures of the lower eyelid contribute to prolapse of the orbital fat pads, and highlight the relevant ligamentous structures, blood supply, and innervation to avoid complications during transcutaneous or transconjunctival orbital fat repositioning. With detailed knowledge of the anatomy of the lower eyelid as outlined in our review, surgeons can improve and optimize outcomes whilst minimizing complications.

Dynamic Measurement and Analysis of Upper Eyelid Changes Using Ultrasound Biomicroscopy

PURPOSE

To define the regular upper eyelid anatomy and their changes during dynamic motion using ultrasonographically depicted structures.

DESIGN

A cross-sectional study.

METHODS

High-resolution ultrasound biomicroscopy (50MHz) was performed on 84 upper eyelids of 42 healthy volunteers without evidence of eyelid conditions. The skin-orbicularis oculi complex (SOOC), levator aponeurosis, and Müller's muscle-conjunctival complex were imaged. The thickness of these structures was measured in primary gaze and downgaze positions.

RESULTS

SOOC and levator aponeurosis thickness was bigger with eyes open than with eyes closed (p < 0.01). With eyes closed, the thickness of SOOC on the pupillary midline and levator aponeurosis was positively correlated with age (p < 0.05, p < 0.01, respectively), and the thickness of levator aponeurosis and SOOC on the pupil midline was also positively correlated with BMI index (p < 0.05). Similarly, SOOC thickness on the medial and lateral canthus line is also positively correlated with BMI index and age (p < 0.05, p < 0.01, respectively). As for the differences between genders, the mean thickness of SOOC and levator aponeurosis was statistically different (p < 0.05, respectively). The magnitude of levator aponeurosis thickness in men varied more than in women in different ocular positions (p < 0.05). All measurements had an intramethod between 0.624 and 0.792, and inter-rater ICC and intrarater ICC between 0.748 and 0.850.

CONCLUSIONS

Ultrasound biomicroscopy represents a noninvasive tool for the visualization of upper eyelid morphology. Expanding its application can help to understand the dynamics of upper eyelid physiological movement, aging, and disease research in different populations and evaluate surgical outcomes.

Lower eyelid entropion in thyroid eye disease

Purpose: To report the clinical features, ultrasound biomicroscopic features, and management outcome in patients presenting with thyroid eye disease (TED) and lower eyelid entropion. Methods: Retrospective interventional case review of patients with TED presenting with lower eyelid entropion over a 12-year period.Results: Five patients (eight eyes) of a total of 1211 presented with lower eyelid entropion as one of the presenting signs of TED (0.41%). The average age was 28.8 years (18-39 years), and three patients were males. Three had systemic hyperthyroidism, and two were euthyroid. Four (80%) had bilateral TED, three had inactive disease, and two were active. The average Hertel exophthalmometry reading was 24.6 mm. All patients had upper lid retraction. Four (80%) had concomitant lower eyelid retraction. Entropion was medial in five and complete in three eyes. Symptomatic corneal epitheliopathy was noted in four eyes. UBM was performed in four eyes which showed a thickened middle lamella. In four eyes (three patients), the entropion was managed conservatively as the patient was not contemplating surgery for proptosis. In the remaining four eyes (two patients) orbital decompression was performed and the lower eyelid retractor release corrected the symptomatic entropion. The average follow-up was 11.6 months (range 1-30).Conclusion: Lower eyelid entropion is a rare presenting sign in TED. The mechanism is multifactorial and could be caused by the thickened and fibrosed lower lid retractors, as demonstrated by UBM. Young age and globe projection may play a role. Decompression approaches that involve lower lid retractor release correct the entropion.