Introduction

Keratoconus is a progressive disorder where central or paracentral thinning of the cornea leads to changes in vision and symptoms of pain and photophobia [1,2,3]. Visual changes occur from steepening of the cornea which leads to progressive, typically irregular astigmatism [2, 4]. Early treatment is through the prescribing of glasses and/or contact lenses and management of associated risk factors such as atopy, sleep apnoea and eye rubbing [4,5,6]. Surgery such as cross linking (CXL), intrastromal corneal ring segments (ICRS) or keratoplasty may be indicated [7,8,9].

Quality of life (QoL) is an important outcome in research in keratoconus treatment and is assessed through standardized questionnaires [10,11,12]. Keratoconus patients have been shown to score lower on the Impact of Vision Impairment (IVI) questionnaire, which measures activity limitation and emotional impact, when compared to other conditions such as diabetic macular oedema and age-related macular degeneration [13]. The Keratoconus Outcomes Research Questionnaire (KORQ), has content on two domains of QoL (symptoms and activity limitation) and has been externally validated for keratoconus [14].

Current literature reporting qualitative analysis of keratoconus patient experience is sparse, to our knowledge there has been only one recent publication [15] Data was reported in this study on patients receiving a single type of treatment for their keratoconus [15]. Knowledge of the patient experience of keratoconus in everyday practice with management utilizing a range of treatments, is needed to ensure current treatment approaches address patient needs [16] and to inform the development of new questionnaires and treatments.

To address the knowledge gaps on QoL impacts of keratoconus in the real-world, this study aimed to evaluate the patient experience of a broad range of keratoconus patients; that is patients treated in a variety of ways such as by rigid gas permeable contact lens, ICRS, CXL, and/or keratoplasty.

Methods

Semi-structured phone and face-to-face interviews were conducted with patients diagnosed with keratoconus. Baseline sociodemographic and medical data was obtained through survey and chart review. The study received ethics approval from the Royal Prince Alfred Hospital Research Ethics and Governance Office (Project Number: 2023/ETH00410) and adhered to the principles of the National Statement on Ethical Conduct in Human Research (2023). Standards for reporting qualitative research were followed during the conduct of the study [17].

Inclusion criteria were patients aged >18 years, diagnosed in at least one eye with keratoconus who provided informed consent to participate in an interview. Keratoconus was diagnosed by the treating clinicians utilizing Pentacam topography. Patients were excluded if they had other ocular pathology and comorbidities that investigators considered would affect QoL (e.g., macular degeneration, retinal detachment), or had psychiatric disorders, other medical conditions or cognitive/linguistic limitations making them incapable of participating in an interview in English. Participants were recruited from corneal clinics at the Sydney Eye Hospital, a quaternary referral eye hospital in Sydney, New South Wales, Australia.

Semi-structured interviews lasting approximately 25 min were conducted within 2 weeks of recruitment. Interviews included broad and open-ended questions exploring different aspects of QoL and were conducted in English. Identifiable data was censored in interviews. An interview guide used to assess the experience of refractive error [18] was adapted for this study. Interviews were transcribed verbatim and transcripts were analysed qualitatively using NVivo Software, Version 12 (QSR International Pty Ltd.). Demographic and clinical data collection were collected at time of recruitment from the patient’s medical record.

Phenomenological analysis was performed where discrete concepts were identified through inductive and deductive processes [19]. Discrete concepts which described the relationship between keratoconus and a participant’s QoL were given a code, consisting of a short descriptor of the concept identified. Codes were grouped into categories through their semantic relationship. Categories were grouped into broader themes. Codes, categories, and themes were discussed by investigators on a weekly basis to ensure a consensus view on emerging data [20] Data collection occurred until thematic saturation was reached, that is where new categories of codes were not identified in subsequent interviews.

Statistical analysis

Descriptive statistics were used for demographic data with analysis in Microsoft Excel.

Results

Participants

Thirty-three patients were interviewed of median age was 37 (range 18 to 65) years with most patients male (n = 25; 75.8%) and single (n = 24; 72.7%). Socio-demographic data and baseline-medical data are reported in Table 1. The most common highest level of educational attainment reported was a Bachelor’s degree (n = 11; 33%). Educational attainment ranged from incomplete finishing of high school to a Master’s degree. Patients resided in regions ranging in remoteness from Modified Monash Model categories MM1 (Metropolitan Areas) to MM5 (Small Rural Towns) [21]. There were 7 distinct self-identified racial backgrounds reported, with Caucasian being the most common (n = 18; 54.5%).

Table 1 Socio-demographic characteristics of patients with keratoconus (n = 33).
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Clinical characteristics of the included patients are reported in Table 2. Time since diagnosis of keratoconus had a median duration of 13 (range: 1 to 41) years and the median age at diagnosis was 22 (range 10 to 9) years. All stages of keratoconus, as classified by the Amsler–Krumeich scale, were represented within the patient cohort (33.3% Stage I, 29.6% Stage II, 7.4% Stage III, 29.6% Stage IV) [22]. Habitual visual acuity (logMAR) ranged from 0.0 to 0.80 in the better eye (median 0.2). Most patients reported using corrective devices (spectacles, contact lenses) (n = 23; 69.7%) and 10 patients reported not using vision correction devices. Reliance on corrective devices varied from constant use to intermittent. Different modalities of contact lenses (soft, rigid gas permeable, scleral, piggyback) were reported. The history of ophthalmic surgery ranged from surgery naïve (n = 13; 39.4%) to multiple surgeries (n = 11, 33.3%). Procedures reported by the patients included corneal crosslinking (CXL) (n = 8; 24.2%), keratoplasty (n = 13; 39.4%), and intrastromal corneal ring segments (ICRS) (n = 1; 3.0%).

Table 2 Baseline clinical characteristics of patients with keratoconus (n = 33).
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Saturation

Phenomenological saturation was reached at 31 participants, with 2 subsequent interviews not revealing new codes. Initial incidence of new phenomena was rapid for the first 10 interviews, where 51% of total unique codes were recorded (Fig. 1).

Fig. 1: Description: Graph of total unique codes over the duration of the study.
figure 1

50% of total codes were reached with the first 10 interviews, and saturation was reached with no new codes after the 31st interview.

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Coding

Phenomenological analysis of quotes (references) and codes revealed 7 distinct themes in the relationship between keratoconus and QoL. (Table 3) They are described further with reference to the specific codes and quotes below and summarized in Table 4. A list of all the unique QoL issues identified is available as supplementary material (Appendix 1).

Table 3 Identified themes and related codes and references for patients with keratoconus (n = 33).
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Table 4 Themes and quotes reported by patients with keratoconus (n = 33).
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Theme 1: Healthcare

Several patients reported negative experiences with availability and quality of treatment; issues included poor access and conflict with practitioners (Table 4, H1,H2). Appointments were frustrating and patient’s first experience with a depressing hospital setting (Table 4, H3,H4). Diagnosis had emotional effects, with recounts of futility, fear, and dismay (Table 4, H5,H6,H7). Treatments, both medical and surgical, were described as limited in effectiveness, and the side effects and recovery were a burden. (Table 4, H8, H9). Personal image was affected by treatment. Contact lenses were described as inconvenient, fragile, and frequently fell out of patient’s eyes (Table 4, H9). Overall, there was expressed frustration with treatment.

Surgery was described as scary and had a challenging recovery period (Table 4, H10, H11). Fears and inconveniences were described during and after surgical treatment (Table 4, H12). Multiple patients expressed their fears when having surgery without general anaesthesia. Patient’s expressed sadness at a perceived lack of cure for keratoconus. (Table 4, H13)

While many negative aspects of treatment were described, patients also described positive aspects, such as excitement at undergoing keratoplasty and improvement in their QoL afterwards (Table 4, H14, H15). Crosslinking provided reassurance to the patients. (Table 4, H16). Both contact lenses and glasses improved vision and QoL (Table 4, H17, H18).

Theme 2: Symptom

Patients described a direct and indirect burden of symptoms. Symptoms were both acute and chronic and included blurred vision, pain, headaches, dryness, irritation, starburst patterns of light, photophobia, watery eyes, sensitivity, poor depth perception, diplopia, loss of peripheral vision, and swollen, red eyes (Table 4, S1, S2, S3, S4, S5, S6). These symptoms occurred in combinations and during acute episodes (infections, hydrops, and graft rejection) as well as chronically.

Visual symptoms inconvenienced patients and impacted daily activities such as computer usage, reading, and self-care routines (Table 4, S7). Non-visual symptoms caused physical discomfort and self-consciousness due to the appearance of their eyes (Table 4, S8). Patients were emotionally impacted due to these symptoms and described annoyance and futility (Table 4, S9). Symptoms were noticed before a formal diagnosis and were often ignored by the patient. Coping mechanisms to avoid symptoms were described by the patients (Table 4, S10).

Theme 3: Career

Impacts on the participants education and early working life were recounted. Education was affected early on in life; patients reported being disengaged as students (Table 4, C1, C2). Schoolwork was affected due to visual symptoms which reduced class participation (Table 4, C3) and support from teachers was limited. (Table 4, C4). Delayed recovery following surgery and associated symptoms were described as causing withdrawal from studies (Table 4, C5). Multiple participants described an inability (both perceived and experienced) to meet vision standards for their ideal career (Table 4, C6); these effects caused frustration, sadness, and regret (Table 4, C7).

Early career opportunities were also reported as limited due to issues with education, perceived liability as well as limited independence (Table 4, C2). Keratoconus patients recounted forced career changes as their condition progressed and their aptitude at work decreased (Table 4, C8, C9). Career progression was affected; patients were terminated from their employment due to their condition or felt unable to seek a promotion (Table 4, C10, C11).

Screen usage and tasks requiring fine detail were two salient aspects of work that were recounted as difficult. Patients described errors they had made with their work and resultant feelings of frustration and incompetence (Table 4, C12). Coping mechanisms included multiple monitors, enlarged font, higher contrast screens, magnification devices and support from coworkers (Table 4, C13). Patients were embarrassed by needing to utilize such coping mechanisms (Table 4, C14).

Theme 4: Enjoyment

A reduced ability to enjoy life was reported. Direct symptoms of the condition or indirect effects due to treatment reduced the patients’ ability to participate in, perform and enjoy pursuits. Activities affected included going to concerts, playing sports, swimming, gaming, and creative pursuits (Table 4, E1). Participants wished for better sight to enable them to enjoy such activities and experiences (Table 4, E2). Sports were mentioned often, with patients reported limited participation in sports and issues with glasses or contact lenses during sporting activities (Table 4, E3).

Patients lost confidence in competitive hobbies (Table 4, E4) and lost passion in their interests (Table 4 E5) had emotional impacts on patients (Table 4, E6). Travel was restricted due to the constraints of hospital appointments. Patients were under stress due to being reliant on treatments (Table 4, E7). Visual enjoyment of experiences such as sight-seeing, attending concerts, or family time was reduced (Table 4, E8, E9, E10). Reading was another issue which affected the enjoyment of movies, musicianship, device usage and television (Table 4, E11).

Theme 5: Relationships

Keratoconus patients described impacts on their relationships with family, friends, and romantic partners. Patients felt poorly understood and isolated (Table 4, R1, R2); isolation occurred due to symptom burden, an inability to socialize and self-consciousness (Table 4, R3,R4). There were image concerns due to symptoms as well as due to the appearance of corneal grafts (Table 4, R5, R6). These concerns were reinforced by discrimination in different social environments (Table 4, R7). Patients expressed wishes to appear ‘normal’ at an early age, particularly in school and work environments. Difficulty recognizing others led to awkward social situations (Table 4, R8). Participants did not to discuss their condition as they worried it would bore or burden others (Table 4, R9). Conflict occurred in social settings due to feelings of frustration, poor ability perceived by colleagues and burden placed on others (Table 4, R10). Patients expressed both feelings of guilt and shame from burdening others as well as appreciation for support from friends and family (Table 4, R11, R12).

Theme 6: Driving

Many patients reported impacts on driving due to poor vision, especially when driving at night, in the rain, or in unfamiliar places (Table 4, D1,D2). This affected the patients’ confidence, driving ability, and their overall life, including relationships, career, and hobbies (Table 4, D3,D4,D5). Coping mechanisms and negative emotions that related to driving were also prevalent (Table 4, D6, D7). Challenges included difficulty reading signs, glare from headlights, and reliance on visual aids (Table 4, D8, D9). Car accidents and fear of crashing were common concerns. Surgery recovery worsened vision and impacted driving safety. Depth perception issues made parking challenging (Table 4, D10).

Acquiring a license, meeting vision standards, and fears of license loss were recurrent sub-themes (Table 4, D11, D12). Discomfort, poor object recognition, and obscured vision characterized driving (Table 4, D13, D14). Shame and judgment were associated with the inability to drive. Driving was reported as crucial for careers and social life. Emotions associated with driving included fear, discomfort, annoyance, and sadness. Concerns for safety led to driving slower or alternative routes (Table 4, D15, D16). Patients reported relying on public transport which was inefficient and unreliable (Table 4, D17).

Theme 7: Financial

Participants described both direct and indirect costs associated with keratoconus. Large one-off financial costs were associated with surgical or contact lens treatment, and smaller ongoing costs with the chronic nature of the condition (Table 4, F1, F2). Ongoing costs included replacement of contact lens solution, medications, nutritional supplements, and visual aids (Table 4, F3, F4). Direct costs were described as expensive and sometimes delayed treatment (Table 4, F5). High-cost items such as glasses and rigid contact lenses were frequently replaced due to damage, loss, or reduced efficacy (Table 4, F4, F6). Indirect costs included treatment due to injuries sustained from poor vision, increased insurance premiums or payment for services to assist with activities of daily living (Table 4, F7, F8).

Due to the early onset of the condition, costs were borne not just by patients, but by their families leading to feelings of guilt, shame or worries of being a burden (Table 4, F9). The younger age at which costs occurred made treatment less affordable relative to patient income (Table 4, F10). The career impacts of keratoconus also limited potential income, and participants described difficulty accessing financial aid. (Table 4, F11, F12)

Other findings

Some phenomena described by patients did not fit under the broad themes described above. Multiple participants reported a reliance on their less-affected eye (Table 4, O1). For multiple participants, the unilateral or asymmetric presentation of their condition resulted in QoL being minimally affected. For most patients interviewed, there was a reported acceptance of the condition and overall emotional impact of their experience. (Table 4, O2, O3).

Discussion

In keratoconus, multiple impacts on a patient’s QoL were found. Healthcare experiences were marked by perceived inefficiency and emotional strain. Symptoms, both visual and non-visual, impeded daily life and required coping mechanisms. Education and careers were affected which limited opportunities in life. Enjoyment of life was limited by the condition. Socially, patients felt isolated, misunderstood, and guilty. Limitations on the ability to drive and financial burdens of the condition reduced independence. The varied codes that arose from phenomenological analysis characterized the complexity between the relationship between keratoconus and QoL.

Kennedy et al described keratoconus as having an impact disproportionate to its clinical severity due to the young age at which patients were affected [23]. Similarly, our patients described being affected at a critical stage of their lives when they were unable to bear the financial costs of the condition and its treatment, were beginning their careers and romantic relationships and had no prior experience with surgery. The early onset, chronic and progressive nature of keratoconus as a cause for reduction in QoL in multiple domains has been described [13, 24]. This was also reflected in our results, where patients described early impacts, chronic symptom burden and fear of progression. In ocular conditions such as macular degeneration, patients have described difficulties with aspects of QoL such as self-care; this was not a prominent theme in our interviewed keratoconus patients [25]. In contrast, qualitative research into nystagmus has shown patient concerns with self-image, which was also present in our study [26]. Of interest was the findings in relation to screen-use, as they are becoming an increasing part of modern society, with our patients having difficulty using screens and taking measures such as increasing font size, higher contrast, and larger monitors.

QoL questionnaire scoring has been shown to not always correlate with clinical measurements such as visual acuity [25, 27, 28]. This relationship was reflected qualitatively in our findings, where patients described reduced QoL despite good visual acuity. Tan et al demonstrated a stronger correlation between reading and mobility scores with best corrected visual acuity (BCVA) in the better eye whereas emotional scores correlated more strongly with the BCVA in the worse eye [27]. This complex relationship between vision and QoL effects was reflected in interview responses in our study. Emotional impacts included fear, anxiety and stress due to the healthcare experiences which related to the treated eyes in this study, while a proportion of participants with unilateral presentations of keratoconus described minimal effects on QoL due to reliance on their better eye.

The identified domains of QoL affected in our keratoconus patients will inform the future creation of robust and comprehensive keratoconus specific QoL measures. Questionnaires such as the National Eye Institute 25-Item Visual Function Questionnaire and IVI have been found to be unable to differentiate clinical subgroups of keratoconus [29,30,31]. While questionnaires specific to keratoconus currently exist such as the KORQ and the Keratoconus End-Points Assessment Questionnaire and Keratoconus Symptom and Severity Questionnaire [32], only the KORQ has been externally validated using modern psychometric methods [14]. The KORQ is also limited to two specific domains of QoL, and does not assess psychosocial impacts [14]. This research has investigated psychosocial elements of keratoconus and described specific effects in different contexts; these data may be utilized to update the KORQ.

There were limitations to this study. Recruitment was from clinics of a public eye hospital, this excluded undiagnosed patients or those seeing private ophthalmologists. This may have contributed to an overrepresentation of experiences related to surgery. The exclusion of patients with other ocular conditions also excluded patients who developed glaucoma and/or cataracts secondary to topical steroid usage following keratoplasty for keratoconus. The qualitative nature of this study may have led to bias due to preconceptions of the researchers. Guidelines for qualitative research by Malterud et al were followed to minimize this bias [20]. Furthermore, open ended questions were used, patients were assured of the anonymity of their responses and self-reflection and feedback with other investigators weekly was employed to reduce inherent bias. Most experiences reported in this study were negative, this may be due to the lack of cure for keratoconus and should not undermine the value of treatments and healthcare to improve patient QoL. In a quantitative study using the KORQ, corneal cross-linking was associated with a significant improvement in most areas of visual functioning and symptoms [33].

In conclusion, keratoconus patient’s lives were impacted significantly with affects across multiple domains. Patients had concerns about their healthcare, symptoms, as well as the psychosocial and economic burden from keratoconus. Future tools which measure QoL in keratoconus should consider these factors.

Summary

What was known before

  • Keratoconus is associated with poorer quality of life scores on standardized questionnaires compared to other conditions. Affected quality of life domains have been identified in keratoconus patients with single treatment modalities.

What this study adds

  • This study has identified unique quality of life domains impacted in patients with none, single or multiple treatment modalities. Identified domains can contribute to the development of robust keratoconus-specific quality-of-life questionnaires, improve clinician understanding of patient’s experiences and inform the development of new treatments.