Patient satisfaction during follow-up care is a key indicator of the success of a surgical procedure. It also serves as a gauge of quality and as the basis for optimization of the postoperative treatment. We use a standardized questionnaire to gauge patient satisfaction after multifocal IOL implantation. All patients give their consent to a follow-up telephone survey when they sign the informed consent form before surgery. The telephone interview, based on the questionnaire and conducted exclusively by a trained staff member, takes place 3 months after IOL implantation.
Patients are asked about their subjective eyesight in the near, distance, and intermediate fields. Optical phenomena such as halos (double images/light effects) and glare sensitivity (while driving under poor visibility) using their binocular vision in everyday activities are graded subjectively by the patients according to their subjective sense of impairment. Additionally, they are asked about impairment of their subjective contrast sensitivity in low light conditions and about their general satisfaction with the results.
The patient must answer the questions on a scale of 0% to 100%, in 10% steps. Because the survey is conducted exclusively by telephone, the scale is precisely explained to patients verbally; the questions on the list are then read aloud to the patient, and the answers given are registered accordingly. The total score is determined according to Table 1.
QUALITY OF BINOCULAR VISION
In the course of this process, the quality of a patient’s binocular vision is assessed. In order to simplify the answering process for patients, the different distances of vision are defined as follows: Near distance is defined as reading distance; patients are therefore asked whether they can read a newspaper without glasses. For the intermediate field, the distance to the computer is chosen as the reference point, and patients are therefore asked whether using a computer without glasses is possible. The distance field is defined as the distance to the television and far distance during car driving, and patients are asked whether they can watch TV and drive a car without glasses.
Naturally, however, there are practical limitations to the questionnaire. For example, we sometimes have null values in the intermediate or distance field because a respondent does not possess a computer or does not drive a car for nonvisual reasons and therefore cannot answer the question.
Following are some examples to clarify the meaning of different percentage answers:
- If the patient replies with 0% to the question about seeing double images/light effects, it means that, by day, he or she either perceives these as not disturbing or does not see them at all.
- If, in response to the question about whether he or she can drive in fog, the patient answers 70%, this means that his or her driving under poor visibility is good.
- If the patient answers 100% to the question about overall satisfaction, this means that he or she is satisfied after implantation of the multifocal IOL and would recommended the lens to others.
CAUSES OF DISSATISFACTION
Whether a given lens is suitable for a patient’s everyday use depends on multiple factors. Dissatisfaction may arise when a patient’s expectations before surgery were unrealistically high. A certain degree of acceptance of, and familiarization with, the concomitant optical phenomena and other side effects can also influence subjective satisfaction after surgery.
In some cases, the result of the implantation leads directly to dissatisfaction, as for example in the case of complications during or shortly after the operation that affect postoperative vision. Detailed preoperative explanations and careful patient selection are therefore necessary in order to give patients a realistic attitude toward expectations.
Another potential source of dissatisfaction is the period of neural adaptation that takes place after multifocal IOL implantation. It is well known that a perceptual adaptation process slowly decreases the symptoms of halos and light sensitivity and that patients gradually find the correct new distance for the sharpest near or intermediate visual acuity. There is no known cut-off time point for this process; however, we believe that 3 months of perceptual adaptation is enough. It is wise to inform patients of this process preoperatively.
There are numerous methods for determining patient satisfaction. In the patient benefit index (PBI) method, for example, patient-relevant benefits are determined preoperatively by having patients assess specified therapeutic aims according to their importance. Retrospectively, after treatment, they then gauge the achievement of these aims.
In our setting, however, patients answer only with regard to the achievement of aims. For instance: Have your expectations been fulfilled? Can you now live everyday life without glasses following the implantation of the multifocal IOL?
Our experience shows that patients who have undergone a refractive lens exchange and multifocal IOL implantation with preoperative hyperopia are, as a rule, more satisfied after surgery than patients with preoperative low myopia, even though their hyperopic preoperative corrected vision was worse by comparison to low myopes. A possible reason for this is that the expectations of hyperopic patients with regard to the results consequently tended not to be as high, and that they were more dissatisfied with their vision before the operation than a low myopic patient.
We frequently observe that, in most everyday situations, patients rely on a good image quality in the distance field or a specific reading distance in the near field, despite their complete independence from glasses. Follow-up care, therefore, already begins with preoperative patient selection and should be carried out conscientiously in order to guarantee the best possible refractive results for the individual patient, even if that would mean forgoing multifocal IOL implantation.
Andreas Frings, MD, practices in the University Hospital Eppendorf, Hamburg, Germany. Dr. Frings states that he has no financial interest in the products or companies mentioned. He may be reached at e-mail: firstname.lastname@example.org.
Toam Katz, MD, is the Medical Manager of Care Vision Eye Clinics in Germany and Austria, and a Senior Ophthalmologist in the University Hospital Eppendorf, Hamburg, Germany. Dr. Katz states that he has no financial interest in the products or companies mentioned. He may be reached at tel: +49 40 74 105 43 75; e-mail: email@example.com.