Safety and efficacy of wiping lid margins with lid hygiene shampoo using the “eye brush”, a novel lid hygiene item, in healthy subjects: a pilot study

There is a need for a tool that allows for the simple and efficient cleaning of the eyelid margin and specifically, a tool that can be used to prevent or treat meibomian gland dysfunction (MGD). The eyelid margin cleaning tool includes a wiping material with a surface capable of cleaning the user’s eyelid margin, a support to which the wiping material is attached, and a gripper attached to the support. The support is equipped with two abutting parts that make contact with the surfaces of the user’s upper (1st part) and lower (2nd) eyelids through the wiping material. These two abutting parts are arranged apart from each other to form a space that can accept the deflected wiping material. The eyeball can be moderately moved backward, and either the upper or lower eyelid can be everted to expose the eyelid margin surface to the surface of the wiping material by placing the abutting parts of the support to which the wiping material is attached on the user’s upper and lower eyelid surfaces and pressing the surfaces with the abutting parts. Accordingly, the surface of the eyelid margin can be efficiently cleaned without touching the eyeball with the wiping material. The support contains curved sections connecting at least one side of the longitudinal ends of the two abutting parts, and the wiping material is attached to the curved section. The region around the eyelid margin, including the inner and outer canthi, can be easily cleaned with the surface of the wiping material attached to the curved section. The support is oval in shape along the contour of the eyeball, and the surface of the eyelid margin can be easily everted along this contour. The gripper is attached to the longitudinal end of the support, and the plane demarcated by the two abutting parts is substantially deviated from the longitudinal axis of the gripper in parallel with it. Because of this design, users can easily repeat lateral movements of the gripper attached to the support in the longitudinal direction and clean the surfaces of their eyelid margins. Since the plane demarcated by the two abutting parts is substantially deviated from the longitudinal axis of the gripper and parallel to it, the user’s nose does not interfere with the repeated lateral movement of the eyelid margin cleaning tool (Fig. 1a and b).

We used Eye Shampoo (MediProduct Co., Ltd., Tokyo, Japan) as a lid hygiene product in this pilot study, and its characteristics and ingredients are shown in Table 1.

Twelve eyes of 6 subjects (6 males aged 32–56 [39.8 ± 9.62] years) with normal meibomian glands were evaluated before and after wiping the lid margins in the following ways: using tap water alone, using Eye Shampoo, using the Eye Brush, or using both Eye Shampoo and the Eye Brush. Each procedure was performed during a different week, and the evaluation was performed just after the procedure. The results after using both Eye Shampoo and the Eye Brush twice daily for 1 month were also evaluated. Scores related to ocular condition, i.e., the tear break-up time (TBUT) (graded on a scale of 0–10), corneal and conjunctival fluorescein/lissamine green/rose bengal staining scores (graded 0–9), lid-margin lissamine green staining scores (graded 0–3), subjective symptoms (graded 0–100, as assessed via a visual analog scale [VAS]), and tear lipid layer interference (graded 1–5, as assessed via a DR-1 tear interference camera [Kowa Co., Nagoya, Japan] according to the grading proposed by Yokoi et al. [8]), were evaluated.

The efficacy of each method was determined based on the washout rate of fluorescein-stained 0.3% Tarivid ophthalmic ointment (Ofloxacin ointment), which was fully applied to the eyelids, including the lid margins (Fig. 2a, b1 and b2). Post-wiping scores were determined for the ointment remaining on the eyelids under microscopic view illuminated by blue light (graded 0–6 based on Table 2, Fig. 2c1 and c2) just after performing each of the four lid hygiene methods described above.

We used Wilcoxon signed-rank tests to analyze all items evaluated in this study. When the efficacies of the 4 lid hygiene methods (water alone, Eye Shampoo, Eye Brush, and both Eye Shampoo and the Eye Brush) were compared, the results were interpreted by taking the multiple tests for significance into account since there were 6 comparison pairs. The Bonferroni method [9, 10] was used to correct for multiple comparisons, and a difference was considered significant when the P-value was less than 0.05/6 = 0.0083. When the efficacy of 3 lid hygiene methods, i.e., water alone, Eye Shampoo, and Eye Shampoo with the Eye Brush, was compared in one-tailed hypothesis (water < Eye Shampoo < Eye Shampoo and Eye Brush) tests, there were 2 comparison pairs, and according to the Bonferroni correction, a difference was considered significant when the P-value was less than 0.05/2 = 0.025. Similarly, when comparing the efficacy of water alone, the Eye Brush, and Eye Shampoo with the Eye Brush in one-tailed hypothesis (water < Eye Brush < Eye Shampoo and Eye Brush) tests, there were 2 comparison pairs, and according to the Bonferroni correction, a difference was considered significant when the P-value was less than 0.05/2 = 0.025. We did not combine the scores from all tests to arrive at one composite score and calculate significant differences. Scores from different investigative modalities were not combined in this study.

This prospective clinical pilot comparative study was registered with the University Hospital Medical Information Network Clinical Trial Registry in Japan (UMIN000016905). We adhered to the tenets of the Declaration of Helsinki, and the ethics committee of the Keio University School of Medicine approved the protocol.

There was no significant deterioration in TBUT, corneal and conjunctival staining scores, lid-margin staining scores or DR-1 scores after any method (Figs. 3, 4, 5, 6 and 7, Additional file 1, 2, 3 and 4). Eyestrain VAS scores significantly decreased with tap water (23.5 (0–25) to 0 (0–0), P = 0.020) (Fig. 3, Additional file 1), eye discharge significantly decreased with Eye Shampoo use (3 (0–9) to 0 (0–1.25), P = 0.036) (Fig. 4, Additional file 2), and dryness decreased with Eye Brush use (12.25 (0–21.25) to 0 (0–5), P = 0.014) (Fig. 5, Additional file 3). Sensations of eye discharge significantly increased after 1 month of using both the Eye Brush and Eye Shampoo (0 (0–5.25) to 5.5 (0–9), P = 0.042) (Fig. 6, Additional file 4).

Wiping efficacy when using Eye Shampoo, the Eye Brush, or both Eye Shampoo and the Eye Brush was significantly greater than that when using tap water alone (two-tailed hypothesis tests and no-correction, P = 0.00319, 0.00319, 0.00213, respectively) (Fig. 8a, Additional file 5). Using both products showed a significantly higher efficacy than using Eye Shampoo alone (one-tailed hypothesis tests and no-correction, P = 0.00883) (Fig. 8b, Additional file 6), but efficacy was not significantly greater than that when using the Eye Brush alone (one-tailed hypothesis tests and no-correction, P = 0.03593) (Fig. 8c, Additional file 7).