Development and validation of quality of life questionnaire in pseudophakic patients in portuguese

1Doutor pela Faculdade de Medicina da Universidade de São Paulo, São Paulo (SP), Brasil; chefe do setor de catarata do Hospital oftalmológico de Brasília, Brasília (DF), Brasil; 2Pesquisador do setor de catarata do Hospital Oftalmológico de Brasília, Brasília (DF), Brasil; 3Doutora do setor de refrativa da Faculdade de Medicina da Universidade de São Paulo, São Paulo (SP), Brasil; 4Doutor do setor de Córnea do Hospital Oftalmológico de Brasília, Brasília (DF), Brasil; 5Doutora do setor de glaucoma da Faculdade de Medicina da Universidade de São Paulo, São Paulo (SP), Brasil; chefe do setor de Glaucoma do Hospital Oftalmológico de Brasília (HOB), Brasília (DF), Brasil; 6Professor livre-docente do Instituto de Psicologia da Faculdade de Medicina da Universidade de São Paulo, São Paulo (SP), Brasil. 7Professor doutor da Faculdade de Medicina da Universidade de São Paulo, São Paulo (SP), Brasil. RESUMO


P
hacoemulsification and IOL implantation using increasingly smaller incisions have allowed rapid visual recovery with low rates of complications in the hands of experienced surgeons, as well as good quality of vision in the postoperative period.Assessment of the quality of vision can be done through various tests, such as those assessing contrast sensitivity, which is the ability to distinguish the details of images and depends on ambient brightness (1)(2)(3)(4) .
In order to provide additional benefits to the visual quality of pseudophakic patients, intraocular lenses (IOLs) have been refined using an aspherical lens design to correct positive spherical aberrations of the cornea (5)(6)(7)(8) .One such aspherical lens is the SN60WF lens, developed from the SN60AT lens, both produced by Alcon Laboratories (Fort Worth, Texas, USA).The former provides greater reduction in spherical aberrations with better vision in low light conditions and increased contrast sensitivity in the postoperative period compared to the latter (5,6,9) .
Monofocal IOLs are traditionally used for intraocular implants in cataract surgery.Do to their lack of optical correction, they do not provide a satisfactory depth of focus at varying distances.Despite the potential benefits of multifocal IOLs, their indications are still limited (10,11) .
More advanced multifocal IOLs aim to provide contrast sensitivity similar that accepted for monofocal IOLs and to induce minimal optical aberrations.However, the scientific literature reports a loss of contrast sensitivity and functional vision associated with photic phenomena that affect patient satisfaction (12,13) .
The aim of this study was to develop and evaluate a quality of life questionnaire for patients undergoing phacoemulsification with implantation of the following IOLs: Tecnis™ MF ZM900 aspherical multifocal lens; Restor™ SN60D3 spherical multifocal lens; SN60WF aspherical monofocal lens; and SN60AT spherical monofocal lens.Inclusion criteria were: Age between 45 and 65 years; literate patients; bilateral senile cataract; corneal astigmatism under 1.00 D in both eyes; pupil diameter of at least 3.5 mm under mesopic conditions, measured using a Colvard pupillometer (Oasis Corporation, Glendora, CA, USA); and absence of any other eye disorders, eye surgery, use of topical hypotensive medications, or other systemic diseases that might affect postoperative vision with decreased contrast sensitivity, such as diabetic retinopathy.Exclusion criteria were: Intra-or postoperative complications; doubts regarding implantation of the IOL in the capsular bag; and IOL decentration greater than 0.5 mm as measured by slit lamp examination.

METHODS
In total, 46 eyes of 23 patients underwent conventional phacoemulsification with implantation of Tecnis MF aspherical multifocal IOLs, and 32 eyes of 16 patients received Acrysof Restor apodised spherical multifocal IOLs.The control group comprised 64 eyes of 32 patients who underwent surgery with implantation of the Acrysof SN60WF spherical monofocal IOL in one eye and the AcrySof SN60AT spherical monofocal IOL in the other eye (Alcon Laboratories, Fort Worth, TX, USA).All procedures were performed by a single experienced surgeon (CTN) using a standardised surgical technique.
The Tecnis ZM900 multifocal IOL features 20 diffractive zones for near and far vision, with an adding power of +4.00 D in its flat refraction, corresponding to +3.20 D in the flat refraction of eye glasses.Therefore, the IOL is completely diffractive, i.e., visual performance does not depend on the pupil.The AcrySof Restor™ IOL has refractive zones for far vision and, in the centre, diffractive zones for near and far vision.It is a pupildependent lens.It has rings of different heights, starting with 1.4 mm in the centre and ending with 0.2 mm in the periphery, when the lens becomes refractive only.The lens has an optical adding power of + 4.00 D in the central 3.6 mm with and +4.00 D in its flat refraction (12,13) .
A significance level of 5% was adopted, using comparison tests such as the Tukey, Kruskal-Wallis, Mann-Whitney, and Chisquare (two-tailed) tests and adjusting the significance level when needed.

RESULTS
The mean age of patients was 60.7 ± 6.6 years in the aspherical multifocal group, 63.1 ± 4.4 years in the spherical multifocal group, and 63.7 ± 4.2 years in the monofocal group.There were no statistically-significant differences between groups for uncorrected far visual acuity and best corrected visual acuity (p = 0.144).There were also no significant differences between groups with regard to the sex of patients.No intraoperative complications occurred.
There was no statistically-significant difference in mean uncorrected monocular far visual acuity in the monofocal group compared to the multifocal groups.Intermediate (50 to 70 cm) and near (30 to 40 cm) visual acuity without optical correction was evaluated using the ETDRS™ chart (Table 1); a statisticallysignificant difference between lenses was found only for intermediate vision, favouring the Tecnis™ MF group (p < 0.001).No patient required optical correction for near or far vision after surgery in any everyday situation.
Mean satisfaction for near visual acuity was statistically higher in the monofocal group (Tecnis™ MF; Restor™) than the multifocal group (SN60AT; SN60WF); there was no difference between the two multifocal groups.Mean satisfaction for near visual acuity was 3.75 (±1.3) in the monofocal group; 8.70 (±0.63) in the Restor™ group; and 9.30 (±0.69) in the Tecnis™ MF group.
Mean satisfaction for intermediate visual acuity was statistically higher in the Tecnis™ group than in the Restor™ and monofocal (SN60AT; SN60WF) groups; there was no difference between the Restor™ and the monofocal group.Mean satisfaction for near visual acuity was 4.00 (± 1.87) in the monofocal group; 5.60 (± 1.05) in the Restor™ group; and 7.80 (± 0.84) in Tecnis™ MF (Table 2).
There was no difference among the three groups in terms of whether patients would recommend this type of surgery.Mean satisfaction for near visual acuity was 9.29 (± 0.   3).
The satisfaction rate for night halos was statistically higher in the multifocal group (Tecnis™ MF; Restor™) than in the monofocal group (SN60AT; SN60WF); there was no difference between the two multifocal groups.The satisfaction rate for glare was 18.8% in the Restor™ group; 21.7% in the Tecnis™ MF group; and none in the monofocal group.The satisfaction rate for day halos did not differ between the three groups (Table 3).
The rate of independence from glasses when using a computer was statistically higher in the Tecnis™ MF group than in the Restor™ and monofocal (SN60AT; SN60WF) groups; there was no difference between the two multifocal groups.The utilisation rate of glasses was 43.8% in the Restor™ group; 62.5% in the monofocal group; and 17.4% in Tecnis™ MF group (Table 4).
The rate of independence from glasses when reading the newspaper, medicine bottles, books, menus, watching pictures, driving, and looking at the watch was statistically higher in the multifocal groups (Tecnis™ MF; Restor™) than in the monofocal group (SN60AT; SN60WF); there was no difference between the two multifocal groups (Table 4).

DISCUSSION
The four groups were compared with regard to age and sex, two variables that might influence patient satisfaction.Mean age was over 60, i.e. patients were possibly economically active.Socioeconomic status and daily/professional activities were not evaluated but are important in selecting patients for multifocal IOL implantation, because patients who perform night activities, such as driving and playing sports, among others, may not have the same level of satisfaction as those who do not perform these activities, due to the influence of photic phenomena such as halo and glare triggered by such lenses.Patients who require a more accurate intermediate vision, especially computer users, may not have the same level of satisfaction as patients who need to read at an average distance of 40 cm.There is a widespread yet undemonstrated notion that women tend to accept photic Night Halos   Assessing satisfaction with regard to independence from glasses among patients submitted to cataract surgery with implantation of Tecnis™ MF, Restor™, SN60AT, and SN60WF lenses phenomena better in exchange for being independent from glasses.Likewise, elderly individuals would tend to be more tolerant of visual quality.We applied the TyPE questionnaire, a satisfaction questionnaire developed to assess quality of life after multifocal IOL implantation, not available in this study.
This is an important method to assess and compare the satisfaction of subjects included in the four groups (17,18) .It is also in agreement with the idea that hyperopic patients would have milder symptoms than myopic patients, although this comparison was not done in this study (19) .
There was no difference in spherical equivalent between study groups.The refractive outcome was very close to emmetropia, which was our goal.This reaffirms the importance of biometry performed by an experienced examiner using the immersion method or interferometry, which are highly accurate.This is important because inducing a negative refractive result would favour uncorrected near vision, but would also worsen far vision.Anyway, this effect would be eliminated when measuring near vision with correction for far vision.Another important point is the fact that no patients had a refractive outcome greater than 1 D, which could lead to increased frequency and severity of photic phenomena (20) .
Our results for uncorrected visual acuity and visual acuity corrected for far vision among patients who received the Tecnis™ MF and Restor™ lenses are in agreement with the literature.In a European multicentre study, Kohnen et al. (21) found that all patients who received Restor™ lenses achieved an uncorrected far visual acuity of 20/40 or better, and 97.5% of patients achieved an uncorrected near vision of 20/40 or better.
Sallet et al. (12) reported uncorrected far visual acuity better than 20/30 in all eyes and uncorrected near visual acuity of Jagger 3 or better in all patients.
These findings are supported by data in the literature showing that multifocal intraocular lenses provide better uncorrected near visual acuity than monofocal lenses (22,23) .
All measures of binocular near visual acuity were better than monocular measures.This has also been observed in previous studies on multifocal lenses (23,24) .
Uncorrected near vision in the Restor™ group was comparable to best corrected near vision in the monofocal group, allowing most daily short-distance activities to be performed without the need for optical correction.Despite the formation of two images, there is only one effective focus, chosen by the patient, which will depend on the distance of the object to be focused on.The good uncorrected near vision obtained in the Restor™ group can be explained by the fact that this lens has an addition power of +4.0 D in its diffractive structure (+3.5 diopters in the glasses plane).This may also explain the fact that corrected near vision was better in the Restor™ group, as the adding power in the monofocal group was limited to +3.0 D.
In our study, uncorrected intermediate visual acuity and best corrected far visual acuity among patients in the Restor™ group was in agreement with the results of Blaylock et al. (25) , where mean visual acuity was 20/36 and 20/38 respectively.However, the same study found better intermediate visual acuity with monofocal SA60AT lenses compared to Restor™ lenses, which was not observed in our study for the assessed distances.Another study that assessed intermediate visual acuity with Restor™ lenses found worse visual acuity for distances of 50, 60 and 70 cm compared to 33 cm.Although these studies found a worse intermediate visual acuity, the average intermediate visual acuity at 70 cm was comparable with that found in our study.
We found a better monocular intermediate visual acuity corrected for far vision in the multifocal groups (Restor™, Tecnis™ MF) compared to the monofocal group (SN60AT; SN60AT) for distances of 40-50 cm.At 50-60 cm corrected for far vision, the Tecnis™ MF group was statistically superior to all other groups.With respect to distances 40-60 cm, the Tecnis™ MF group was superior.For 50-70 cm, an improvement in the mean and median was found in the monofocal group.If intermediate vision was assessed at distances greater than 70 cm, a statistically significant difference in visual acuity favouring the monofocal group (SN60AT; SN60AT) would probably be found.There was no disagreement between our results and the literature on near and intermediate visual acuity favouring multifocal lenses over monofocal lenses (22,(28)(29)(30) .Hutz et al. (28)  Hida WT, Nakano CT, Yamane I, Motta AFP, Tzeliks PF, Guimaraes AS, Alencar LM, Ventura DSF, Alves MR, Kara José Júnior N Leyland et al. (22) did a meta-analysis of studies comparing multifocal and monofocal lenses and reported a better uncorrected far visual acuity in patients with monofocal lenses, while other studies found no difference (29,30) .This can be explained by the fact that part of the light is split to a focus anterior to the retina in near vision, while with monofocal lenses all energy is concentrated in the far focus.
The assessment of quality of life is based on the patient satisfaction questionnaire and it is one of the most important subjective evaluations on the outcome of cataract surgery.In our study, all patients who completed the questionnaire had undergone cataract surgery with implantation of monofocal or multifocal lenses.Thus, our data reflect the satisfaction of patients undergoing cataract surgery only.It is worth noting that our results reflect a high level of satisfaction with visual recovery as well as independence from glasses (17,31,32) .
The multifocal Tecnis™ and Restor™ MF groups showed a higher level of satisfaction with near vision and a lower need for glasses than the monofocal group, as well as a higher incidence of halo and glare.Several studies showed results similar to ours using the same satisfaction questionnaire on patients submitted to cataract surgery with implantation of different types of multifocal and monofocal intraocular lenses (17,(32)(33)(34)(35) .Berdeaux et al. (33) found similar results when comparing Restor™ (MA60D3) and AcrySof™ Monofocal (MA60BM) lenses.
However, it should be noted this is a subjective assessment based on data collected with patients in the postoperative period.It aims to quantify ophthalmic results among patients, but it reflects the impression of surgeons as to the results.Despite its design and scope limitations, our assessment has accomplished his goal.

CONCLUSION
After analysing the data obtained in this study, we can conclude that the Tecnis™ and Restor™ MF multifocal intraocular lenses led to a visual acuity comparable to monofocal SN60WF and SN60AT lenses for far vision and to a better uncorrected near vision.All lenses caused less spherical high-order and total aberrations than SN60AT monofocal lenses.The Tecnis™ and Restor™ MF lenses provided a higher level of satisfaction with near vision and independence from glasses, as well as a higher incidence of photic phenomena, than the SN60AT and SN60WF monofocal lenses.The modified Type questionnaire significantly influenced the satisfaction of patients submitted to cataract surgery with implantation of different intraocular lenses.
Prospective non-randomized comparative study on 142 eyes of 71 selected patients.Subjects were recruited between March 2006 and September 2007.Evaluations took place from January 1, 2008 to August 25, 2009 at a single centre using a single-blind, prospective, comparative design in the Cataract Unit, Department of Ophthalmology, University Hospital of the São Paulo University.The study was conducted in accordance with ethical standards for clinical and surgical research and was approved by the Ethics Committee for the Analysis of Research Projects (CAPPesq) of the Clinical Board of the University Hospital of the São Paulo University.

Table 4
reported similar data on the superiority of Tecnis™ MF lenses for intermediate vision compared with Restor™ and other monofocal lenses.