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ObjectiveSutureless cataract surgery has been growing in popularity over the last decade. These clear corneal incisions allow for rapid visual recovery after phacoemulsification, but may be associated with an increased risk of endophthalmitis. The purpose of this study was to evaluate the effect of intraocular pressure (IOP), location, and angle of cataract incisions on wound apposition and sealing in postmortem globes.MethodsThis was an ex vivo laboratory investigation of 20 rabbit eyes and 14 human eyes. Self-sealing clear corneal, limbal, and scleral incisions were created and IOP was controlled with an infusion cannula. Incisions were made at a variety of angles. Optical coherence tomography was used to image the incisions in real time as the IOP was varied by raising and lowering the infusion bottle, so as to simulate the variation in IOP occurring with blinking or squeezing of the eye.ResultsWith each type of incision, optical coherence tomography demonstrated the dynamic nature of cataract wound morphology as IOP was varied. Higher IOPs, in general, were associated with more tightly sealed wounds than lower IOPs, but this varied according to the location and angle of the incisions. More perpendicular incisions, relative to the surface tangent, sealed less well than incisions created at smaller angles at higher levels of IOP; At lower IOPs, the reverse relationship was observed such that more perpendicular incisions sealed less well than smaller incision angles.ConclusionChanges in IOP may result in variable and sometime poor wound apposition in sutureless cataract incisions. The type of incision and angle of the incision may affect the likelihood of inoculation of the aqueous humor with potentially pathogenic bacteria. For each type of incision, there may be a critical angle at which the incision is better able to withstand fluctuations in IOP.

OBJECTIVE:To estimate the psychometric properties of a vision-targeted measure of health-related quality of life, the National Eye Institute-Refractive Error Quality of Life survey (NEI-RQL), which includes 13 scales designed to assess the impact of refractive error and its correction on day-to-day life. DESIGN:Cross-sectional survey. PARTICIPANTS:The NEI-RQL was self-administered by 667 myopes, 380 hyperopes, and 114 emmetropes recruited from the practices of 6 medical centers. All participants had near and distance visual acuity of 20/32 or better in the worse eye while benefiting from their current method for correction of refractive error (glasses, contact lens, refractive surgery). METHODS:Mean scores, standard deviations, internal consistency reliability, and test-retest intraclass correlations were estimated for the NEI-RQL scales. Item discrimination was assessed by item-scale correlations. Construct validity was evaluated by assessing the sensitivity of scale scores to type of refractive error, type of refractive error correction, and spherical equivalent. Construct validity of the NEI-RQL was compared to those of the Medical Outcomes Study 36-item short-form health survey (SF-36) and the National Eye Institute Vision Functioning Questionnaire (NEI VFQ-25) in a random subsample of respondents. MAIN OUTCOME MEASURES:The 13 NEI-RQL scales-clarity of vision, expectations, near vision, far vision, diurnal fluctuations, activity limitations, glare, symptoms, dependence on correction, worry, suboptimal correction, appearance, and satisfaction with correction. RESULTS:Emmetropes tended to score significantly better on the NEI-RQL scales than myopes and hyperopes. The method of refractive error correction was also associated with NEI-RQL scores. In addition, the NEI-RQL multi-item scales accounted for 29% of the variance in the NEI-RQL satisfaction with correction item beyond that explained by the SF-36 and the NEI VFQ-25. CONCLUSION:These results support the reliability and construct validity of the NEI-RQL. The instrument appears to be useful for comparisons of people with different types of correction for refractive error.

ObjectiveClear corneal cataract incisions without sutures allow for rapid visual rehabilitation after phacoemulsification but might be associated with an increased risk of postoperative infection. The goal of this study was to examine in vitro dynamic changes in unhealed clear corneal cataract incisions that might adversely affect the risk of intraocular infection.DesignLaboratory investigation.MethodsSelf-sealing clear corneal incisions were created in cadaveric human and rabbit eyes, and intraocular pressure was controlled with an infusion cannula. Incisions were imaged in real time using optical coherence tomography as intraocular pressure was varied. Using an artificial anterior chamber, India ink was applied to the surface of cadaveric human corneas with clear corneal incisions to detect possible flow of surface fluid along the incision. Intraocular pressure was varied by raising and lowering the infusion bottle so as to simulate the variation in intraocular pressure that would occur with successive blinks.ResultsOptical coherence tomography demonstrated variation of corneal wound morphology in response to changes in intraocular pressure. Higher intraocular pressures were associated with close apposition of the wound edges, with no tendency for wound leakage. At low intraocular pressures, however, wound edges tended to gape, starting at the internal aspect of the wound. One incision opened along the entire length, allowing fluid flow across the cornea. Histologic examination revealed India ink particles in all incisions for up to three fourths of the length of the wound.ConclusionsTransient reduction of intraocular pressure might result in poor wound apposition in clear corneal incisions, with the potential for fluid flow across the cornea and into the anterior chamber, with the attendant risk of endophthalmitis.

ObjectiveTo identify the content area for a questionnaire designed to measure the vision-targeted, health-related quality of life for persons with well-corrected refractive error.DesignCross-sectional study.ParticipantsFifty-two focus groups were conducted with 414 patients from 5 geographically diverse ophthalmic and optometric sites to identify the content area of a questionnaire for use among persons with myopia and hyperopia.MethodsA standard protocol was used to structure each focus group discussion, and groups were led by centrally trained moderators at each participating site. Results were summarized and analyzed using a standard set of codes. Qualitative and quantitative analyses were conducted.Main outcome measureSelf-reported observations or comments about vision, vision correction, and other aspects of quality of life.ResultsAmong the 414 participants, 9262 mentions of comments were recorded. The most frequent comments reported by participants were about types of vision correction, followed by comments with their own vision and vision-related symptoms. The distribution of comments by topic domain was generally similar across types of correction and type of refractive error. The most frequent specific comments about glasses concerned problems with reading, adjustment between near and far vision, and appearance. The most frequent comments about contact lenses included those on symptoms such as dry eyes, itching and tired eyes, and headaches, and negative comments about ease of use. The most frequent comments among patients with surgical correction concerned fewer driving problems; fewer symptoms; and improvement in vision, recreation, and comfort. Participants provided equal numbers of positive and negative comments about glasses. Twice as many positive as negative comments were given by contact lens wearers, and 4 times as many positive comments were provided by patients who had undergone surgical correction.ConclusionsUsing focus groups, we were able to identify content areas and aspects of visual functioning in persons with refractive error that are not measured by standard visual acuity testing in the clinic or by other vision-targeted, health-related quality of life instruments such as the 25- or 51-item National Eye Institute-Visual Functioning Questionnaire. The similarity of problems mentioned across refractive error type and correction method suggests it will be possible to develop a single questionnaire with adequate content validity to compare the impact of different modes of correction in vision-targeted, health-related quality of life.