In the treatment of visual acuity deficiencies, correction by means of eyeglasses or contact lenses is used by a large percentage of the population. Such visual acuity deficiencies include hyperopia or far-sightedness, myopia or near-sightedness, astigmatisms (caused by asymmetry of the eye) and presbyopia (caused by loss of accommodation by the crystalline lens).
The selection of the correct contact lens by professionals such as optometrists, ophthalmologists, opticians and/or technicians (referred to herein as a “licensed contact lens fitter”) for a patient is important to providing the required level and quality of vision, while simultaneously protecting eye health and delivering appropriate wearing comfort. This relatively “optimal” corrective lens selection is sometimes achieved empirically by determining the most correct lens by utilizing the output from information supplied by instrumentation. In other cases, the “correct” contact lens selection requires patient-specific and/or on-eye diagnosis utilizing a trial lens that has historically been supplied to the licensed contact lens fitter in two fundamental ways.
In the first case, the licensed contact lens fitter provides empirical information to the manufacturer. The manufacturer interprets this supplied data, and provides a trial or diagnostic contact lens to the fitter for on-eye evaluation. Data collected by the licensed contact lens fitter during the patient-specific evaluation process is then supplied to the manufacturer and a different lens is re-supplied to the fitter for the consumer. Sometimes success is achieved with the first lens sent to the fitter by the manufacturer but many times, the “best” lens requires two or more iterations by the manufacturer, and can take weeks or months.
In the second case, and in an effort to speed the diagnostic and dispensing process, the manufacturer will provide the licensed contact lens fitter with a trial or diagnostic set of lenses to be used for all patients. These diagnostic contact lens sets may range in size from 12 to more than 200 lenses, depending on the complexity of the contact lens design and/or the desire of the fitter to improve the probability of having the “correct” lens for the consumer on the premises. The primary intent of trial or diagnostic lens sets is to use the lenses to ascertain or diagnose the “correct” lens for the consumer so that the correct lens can then be ordered from the manufacturer for the consumer. This also means that the diagnostic lenses are used multiple times and with multiple consumers, and disinfected between use. With the larger trial or diagnostic lens sets, it is possible that the “correct” lens may exist within the parameters of the set and, in these cases, some licensed contact lens fitters will dispense or sell the lens from the set. Once this is done, the fitter will then order a replacement trial or diagnostic lens for his set.
In the first case, disadvantages may include the consumer's inconvenience because the licensed contact lens fitter may require the consumer to have multiple visits to the fitting premises to try the various trial lenses ordered from the manufacture. Another drawback may be the time required of the fitter to achieve the correct lens fit. Yet another drawback may be that there is a greater potential for a fitter to accept a marginally good lens for the consumer rather than endure greater inconvenience by ordering a potentially better fitting lens from the manufacturer.
In the second case, drawbacks may include that the trial or diagnostic lens sets can be expensive for the licensed contact lens fitter, thereby inhibiting a large number of fitters from utilizing this method. Another drawback may be that since the lenses are intended to be multi-use, the licensed contact lens fitter must properly disinfect the diagnostic contact lenses in-between use with different consumers to avoid the transmission of disease, or related liabilities. Yet another drawback may include that, despite the fact that larger trial or diagnostic lens sets provide a higher probability of selecting the “correct” lens more effectively and efficiently, the actual procedure of utilizing the set may be confusing.