Contact lenses (CLs) are widely used for vision correction, with more than 140 million users worldwide, owing to their functional and cosmetic benefits (1). The growing demand for comfortable and cosmetically appealing alternatives to spectacles has further increased their popularity. However, this rise in usage has also highlighted a critical challenge: ensuring proper compliance with contact lens care, particularly with storage case hygiene (2).

Compliance in the context of CL use refers to the extent to which wearers adhere to recommended protocols for cleaning, storage, and maintenance, as advised by eye care professionals. Despite receiving instructions, both adult and younger users often exhibit poor adherence due to negligence, misunderstanding of guidelines, or irregular wear patterns (3). This non-compliance substantially elevates the risk of ocular complications such as microbial keratitis (MK), contact lens peripheral ulcers (CLPU), and contact lens-induced acute red eye (CLARE). Importantly, the contact lens storage case (CLSC) itself serves as a major reservoir for microbial contamination, with studies reporting contamination rates between 58% and 85%, even among asymptomatic wearers. Pathogens such as Pseudomonas aeruginosa, Serratia marcescens, Staphylococcus aureus, fungi, and Acanthamoeba are commonly isolated from CLSCs (4).

Previous studies have documented that 40–91% of lens wearers demonstrate non-compliance with care and hygiene practices, depending on factors such as lens type, replacement schedule, and cleaning regimen. Notably, up to 80% of CL-related complications are considered preventable through proper adherence to hygiene and storage practices (5). These findings underscore the importance of consistent patient education and effective communication from practitioners to improve compliance levels.

Against this background, the present study focuses specifically on CLSC hygiene, an area often overlooked despite its critical role in preventing infections. The study evaluates cleaning routines, replacement frequency, and storage methods among CL wearers visiting a tertiary eye care hospital. Furthermore, it examines the type of instructions provided by eye care professionals and assesses the level of awareness and perceived risk among users. By doing so, this study adds to existing literature by providing insights into real-world compliance patterns in an Indian tertiary care setting, helping to identify gaps that can be targeted through improved patient education and counseling.

Ethical approval for this study was obtained from the Institutional Review Board of Sapthagiri Institute of Medical Sciences and Research Center (Ref No: SIMS & RC/EC-14/Stu-09/2024-25). The study was conducted in the contact lens department of the same institute between August and November 2024. The target population comprised contact lens users attending a tertiary care hospital. A total of 103 participants were enrolled in this cross-sectional study. Individuals using daily disposable CLs were excluded, as they do not require storage cases. Only responses from non-daily disposable lens wearers who owned a storage case were included in the final analysis.

A custom-designed, self-administered questionnaire was developed using Google Forms. The questionnaire was structured into five sections.

The first section gathered demographic information, including age, gender, and educational background. The second section addressed general aspects of CL use, such as lens type, usage patterns, replacement schedules, duration of wear, care products used, and purchase behaviors. Participants using daily disposable lenses were instructed to discontinue the survey and were excluded from the study. The third section focused on CLSC practices, including cleaning methods, drying habits, replacement frequency, solution handling (e.g., topping off), and storage location. The fourth section examined the participant–practitioner relationship, specifically whether oral and/or written instructions on CLSC maintenance were provided and if written guidance was later reviewed. The final section explored participants’ perceptions of the consequences of poor storage case hygiene and their risk assessment of non-compliant behaviors, rated on a scale from 1 (no risk) to 5 (maximum risk).

Participants were informed about the study’s purpose and assured that participation was voluntary, with the option to withdraw at any stage without consequences. A patient information sheet was provided prior to enrollment, and informed consent was obtained online. The questionnaire was distributed via Gmail, WhatsApp, Facebook, and Instagram and was available in both English and Kannada. Participants were requested to complete the form within the Contact Lens Outpatient Department (CL OPD).

Data recorded electronically were transferred to Microsoft Excel for processing. Categorical variables were summarized using frequencies and percentages. Nonparametric analysis was used for statistics, and P-values were calculated using statistical package for social science (SPSS) (version 20). A P-value ≤ 0.05 was considered statistically significant.

A total of 103 participants were included in this study, with a majority being female (69.9%). The age range was 16–32 years (mean: 24.68 ± 3.33 years). A self-reported survey was utilized to assess compliance with hygiene and replacement practices of CLSCs among users attending a tertiary care hospital.

Consistent with findings by Gammoh et al. (6), MPSs were the most commonly used care product in this study, reported by 78.6% of participants. MPS is often preferred for its ease of use, convenience, and cost-effectiveness, as it combines cleaning, rinsing, and disinfection in one solution.

Regarding contact lens case hygiene, 78.6% of respondents reported cleaning their cases; however, only 9.7% cleaned them daily, 21.4% weekly, and 17.5% monthly. Notably, 21.4% never cleaned their cases, a practice known to contribute to microbial contamination, as highlighted in previous studies (6). Similarly, Gammoh et al. (6) reported a 76.5% contamination rate associated with poor cleaning habits.

Unlike Cardona et al. (7), who found that a majority stored their lens cases in bathrooms—environments prone to contamination—this study found that participants commonly stored their cases in cleaner environments, such as cupboards (34%), tables (33%), or bedrooms (8%), with only a small proportion using bathrooms (2%) or washrooms (10%). This suggests a relatively better awareness of hygienic storage practices among our participants.

Compared to a study by Zainodin et al. (8), which reported 52% non-adherence to lens care among young users, our findings show a higher rate of moderate compliance (68%) among participants aged 16–32. Furthermore, it also reported a 48% non-compliance rate; our study found a significantly lower rate (2.9%), reflecting greater awareness of the risks associated with poor hygiene, such as bacterial keratitis, corneal ulcers, fungal or amoebic infections (e.g., Acanthamoeba), and oxygen deprivation-related complications.

All participants owned their own CLSC, suggesting access to appropriate lens care tools. However, lens case replacement practices remained suboptimal. Only 19.4% replaced their cases when damaged, lost, or visibly dirty, and 3.9% never replaced them—supporting prior findings by Madhavendra et al. (9) and Thakur et al. (10) on the role of contaminated cases in MK.

Thakur et al. (10) also reported a higher rate of MK in low-compliance groups (P < 0.05). In our study, moderate awareness of CLSC-related risks was observed. While only 11.7% perceived poor cleaning as high risk, 35.0% rated it as medium and 46.6% as moderate risk (P = 0.527). This highlights the need for reinforced education on the importance of consistent case hygiene to prevent avoidable complications.

In conclusion, the findings indicate moderate awareness among contact lens users regarding the risks of improper lens and storage case care, though gaps in practice persist. While many participants acknowledged the importance of hand hygiene, regular cleaning, and timely case replacement, fewer recognized these behaviors as high-risk, suggesting an underestimation of potential health consequences. Although general knowledge exists, consistent adherence to recommended practices appears limited. These results underscore the need for targeted patient education by eye care professionals, reinforcing the importance of proper hygiene and maintenance to prevent infections and enhance ocular health among contact lens wearers.