Within the last three decades, the ophthalmic field has made great strides in refractive surgery. Laser in situ keratomileusis (LASIK), for example, accounted for approximately 600,000 surgeries in 2015, with most patients reporting satisfaction following the procedure.1
While this surgical intervention generally improves vision, we at the US Food and Drug Administration (FDA) have received reports of some patients experiencing debilitating ocular and visual symptoms—such as dryness and glare—that significantly interfered with their daily functioning following LASIK. In response, the FDA formed a collaborative effort with the National Eye Institute (NEI) to develop a questionnaire to better measure patient symptoms following LASIK. The LASIK Quality of Life Collaboration Project (LQOLCP) enlisted the clinical expertise of the Navy Medical Center San Diego and five civilian clinical sites across the United States to evaluate the tool.2
|Table 1. Overview of LASIK Quality of Life Collaboration Project|
|Pilot||Compare patient-reported outcomes (PROs) of subjects using web-based questionnaires vs. paper versions of the same validated questions||NEI|
|Phase I||Design a web-based instrument for assessing PROs appropriate for the evaluation of healthcare-related quality of life issues in LASIK patients||Emmes (NEI contract research organization)|
|Phase Ia||Conduct cognitive interviews to ensure ease of question understandability, user-friendly format, and comprehensive coverage of issues related to LASIK||Rand through Emmes|
|Phase II (PROWL-1)||Determine an initial estimate of the prevalence of post-LASIK PROs in a select patient population of naval LASIK patients as well as a step in the validation of the questionnaire||Naval Medical Center San Diego|
|Phase III (PROWL-2)||Further validate the newly developed questionnaire in the general population||National multicenter NEI Intramural clinical study|
Based on findings from LQOLCP pilot work showing the equivalence of paper and web-based ocular surface symptom questionnaires, the group developed a questionnaire that addressed many of the concerns mentioned in the literature following LASIK surgery, including: expectations prior to surgery, visual disturbances and satisfaction with vision and surgery.
In addition, we incorporated portions of legacy questionnaires such as the NEI Visual Function Questionnaire and Refractive Error Quality of Life Instrument, the Ocular Surface Disease Index and questionnaires assessing work productivity, depressive and anxiety symptoms, optimism, health proneness and social desirability responses.3
We then used the resultant multi-domain questionnaire in the Patient-Reported Outcomes with LASIK (PROWL) studies to evaluate the measurement properties of these scales (i.e., glare, halos, double images, starbursts, satisfaction with vision and satisfaction with surgery).
The PROWL-1 study was conducted at the Navy Medical Center San Diego, and the PROWL-2 at five private practice and academic clinical centers across the United States. Both studies were designed to determine how well the scales measured the concept of symptom burden on patients and to provide preliminary estimates of the prevalence of these symptoms in the pre- and post-LASIK patient population. We administered the questionnaires prior to LASIK surgery and following surgery for up to three months (PROWL-2) and six months (PROWL-1).
|Table 2. Administrative Groups Involved in the Conduct of the PROWL Studies|
|Study Group and Administration Operational Group (subset of Study Group)||Designed the protocols and questionnaire; Monitored study conduct||FDA (n=8 members) NEI (n=5 members) |
Department of Defense (n=2 members)
|Steering Committee||Independently reviewed the protocols and study results, providing feedback and edits||Two patient representatives|
One member from each of the following: American Academy of Ophthalmology; American Optometric Association; American Society of Cataract and Refractive Surgery; Department of Defense; International Society for Quality of Life Research; NEI; Society for Clinical Trials
|Clinical Sites||PROWL-1||Naval Medical Center San Diego|
|PROWL-2||Durrie Vision; 20/20 Vision Indianapolis; Stanford University School of Medicine; The Johns Hopkins University Wilmer Eye Institute; Vance Thompson Vision|
Our studies found that the scales measured the concepts of interest and were responsive to a change in the clinical state.3,4 Notably, we found that patients are more reluctant to report negative symptoms to their eye care provider than on questionnaires, possibly due in part to social desirability, because the responses to the questionnaire were “anonymous.”4 This underscores the importance of administering standardized questionnaires, which measure concepts of interest to patients and providers, both before and after refractive procedures.
These results suggest the newly developed scales are a useful adjunct to the clinical examination to help elicit unspoken symptoms that can impact patients’ satisfaction with their surgical outcomes.
We hope these publicly available scales will be used not only by device manufacturers in clinical trials, but also in a host of other health care contexts, including assessment of long-term LASIK outcomes.2 Only by listening to the patient’s perspective during the development, evaluation and use of medical devices will we ensure the devices address patients’ needs.
Dr. Tarver is a medical officer in the Division of Ophthalmic and Ear, Nose and Throat Devices, Office of Device Evaluation, Center for Devices and Radiological Health (CDRH), FDA, in Silver Spring, Md.
Dr. Hilmantel is an expert optometrist in the Division of Ophthalmic and Ear, Nose and Throat Devices, Office of Device Evaluation, CDRH, FDA.
Dr. Eydelman is the director for the Division of Ophthalmic and Ear, Nose and Throat Devices, Office of Device Evaluation, CDRH, FDA.
1. Statista. Number of LASIK surgeries in the United States from 1996-2020 (in thousands). www.statista.com/statistics/271478/number-of-lasik-surgeries-in-the-us. Accessed April 19, 2017.
About the Project