352 (100%) patients with involutional eyelid deformities aged 47.0 ± 9.6 years were examined. 87 (24.7%) had hyperextensible eyelids (HES) with blepharochalasis in 40 (11.4%) cases, hyperelastosis in 28 (7.9%) patients, and a combination of these features in 19 (5.4%) cases. The control group consisted of 53 (15.1%) patients without HES. Patients with HES had: hypotonia of the lower eyelids, thinning dry skin in the form of folds and wrinkles with free displacement of tissues, ptosis of eyebrows, lacrimal glands, hypoplasia of natural folds, etc.

The diagnosis of HES was performed using four tests: 1) vertical distraction of the upper eyelids (McNab A.A., 1997); 2) vertical distraction of the lower eyelids (McNab A.A., 1997); 3) horizontal distraction of the upper eyelids (Iyengar S.S., Khan J.A., 2007) and 4) dystopia of the external eye angle (Grishchenko S.V., 2013). Thus, in the control group the maximum linear values were: vertical distraction of the upper eyelids 6.31 ± 0.47mm, lower eyelids 5.21 ± 0.58mm; horizontal distraction of the upper eyelids 4.62 ± 0.55mm and dystopia of the outer corners of the eyes 5.23 ± 0.5mm, while in patients with HES the minimum values in similar tests were: 7.90 ± 0.79, 7.72 ± 0.73, 6.27 ± 0.55 and 5.41 ± 0.50mm, respectively, which may be an objective diagnostic algorithm for HES. Surgical biopsies of eyelid tissues of 29 patients with HES and control group were studied.

Typical pathomorphological tissue changes in hyperextensible eyelids were revealed: collagen and elastin degradation in the eyelid skin, circular eye muscle, tarsal plate, meibomian glands, palpebral conjunctiva, hemomicrocirculatory vascular lesions with signs of chronic aseptic inflammation, the marker of which is elastolytic metalloproteinase 9 (MMP-9). Thus, patients with HES require accurate diagnosis at the planning stage of blepharoplasty with the use of low-traumatic and eyelid-strengthening techniques.