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Revista Brasileira de Oftalmologia

Print version ISSN 0034-7280

Rev. bras.oftalmol. vol.72 no.3 Rio de Janeiro May/June 2013 



Knowledge in refractive surgery among medical students State University of Londrina



Aluisio Rosa Gameiro FilhoI; Nathalia Mayumi Thomaz de AquinoII; Eliana Barreiros de Arruda PachecoIII; Ana Paula Miyagusko Taba OguidoIII; Antonio Marcelo Barbante CasellaIII

ISixth Year Medical Student at the State University of Londrina (UEL), Londrina/PR, Brazil
IIProfessor of Ophthalmology at the State University of Londrina (UEL), Londrina/PR, Brazil




OBJECTIVE: Evaluate the knowledge of medical students from Universidade Estadual de Londrina (UEL), about refractive surgery, as well as analyzing the percentage of students that presents refractive errors, their correction methods and their interest (or not) in the surgical procedure.
METHODS: We conducted a survey using self-evaluation questionnaire (previously tested) among 154 medical students from first to fourth year, between september and november 2011.
RESULTS: It was reported that 70.8% of students had some type of refractive error, and myopia was the most prevalent,with 72.5% of students with refractive erros presenting it, with or without other refractive errors associated. The glasses were the most used method of visual correction . About refractive surgery, 85.7% of students had already heard about, but only 42.9% knew how the procedure is performed, and the ophthalmologist was the main source of information on the subject, to 23.5% of students. Only 43.2% of students have an interest in surgery, and only 3 (1.9%) students have been undergoing the procedure.
CONCLUSION: There has been little information and knowledge about refractive surgery among medical students,which affects their interest in undergoing the procedure, which maybe due the fact that many of them do not have the most adequate source of information to obtain knowledge about the subject.

Keywords: Students, medical; Myopia; Visual acuity; Refractive errors; Knowledge




Refractive surgery consists of the entire surgical procedure intended to correct a refractive error. It is a relatively recent surgical procedure dating back to 1898, when Dr Lendeer Jans Lans published his results on keratectomies and thermokeratoplasties performed on rabbits to treat astigmatism(1). In 1933, the Japanese ophthalmologist Sato began a study on a patient with acute keratoconus associated with rupture of Descemet's membrane, which lead to a flattening of the cornea and a reduced degree of myopia. This lead him to carry out the first anterior and posterior keratotomies in 1939 to treat astigmatism and keratoconus. However, it was only after the PERK (Prospective Evaluation of Radial Keratotomy) study, published by the National Eye Institute in 1981, that radial keratotomy began to gain global significance. Since then, procedures have evolved at an impressive pace given the considerable interest by patients, doctors and researchers in finding a definitive alternative to wearing glasses.

There are a number of surgical procedures which can be performed in order to correct ametropic eyes, such as intraocular lenses and intracorneal implants. However, the most commonly used methods, such as PRK (Photorefractive Keratectomy) and Lasik (Laser Assisted in Situ Keratomileusis), employ the excimer laser(2). Such procedures are fast and safe and have a lower rate of complications than the procedures more commonly used in the past.

This study analyses the prevalence of refractive errors in medical students at the State University of Londrina (UEL) as well as the most commonly used methods of visual correction. It also analyses the number of students who have already undergone refractive surgery and assesses the students' knowledge of and interest in refractive surgery, based on a study by Kara José(3) on students from ABC's Medical School.



The study was conducted from September to November 2011 at the Centre for Health Science (CCS) of the State University of Londrina and included 320 first- to fourth-year medical students.A standardised self-administered questionnaire (Annex 1) with 30 questions, 26 of which were multiple choice, was completed by the students. The questionnaire had previously been tested on first year physiotherapy students at the State University of Londrina. The students were asked about their epidemiological characteristics, whether they had myopia or other refractive errors (astigmatism, hyperopia, presbyopia), the correction methods they used, their knowledge of and interest in refractive surgery, their expectations regarding the procedure, and their sources of information. This was done on the basis of a similar study conducted at ABC's Medical School(3).

The questionnaires were administered during school hours, therefore they were only completed by students who attended their course when the survey was applied and who wanted to take part in it — a total of 154 students.

Only selected data from the questionnaire were used. The remaining data may be used in future studies.

The study was approved by the medical school's Research Ethics Committee through its Opinion 039/2011. All the volunteers were informed about the study's objectives and procedures and provided their informed consent.



Of the 154 participants, 109 (70.8%) stated they had some kind of refractive error, 38 (24.7%) stated they had no visual impairment, 4 (2.6%) could not answer, and only 3 (1.9%) confirmed they had undergone refractive surgery.

As shown in Table 1, out of the 109 students with refractive problems, 44 (40.4%) had myopia alone, 35 (32.1%) had myopia and astigmatism, 21 (19.3%) had astigmatism alone, and 9 (8.3%) had other refractive errors (or a combination of errors)



The average age of participants was 21.88 years (Standard deviation: 3.2). Regarding race, 126 (81.8%) self-identified as white, 17 (11%) as yellow, 10 (6.5%) as brown and only 1 (0.6%) as black.

With regard to gender, 68 (44.2%) were male and 86 (55.8%) were female. Among the male participants, 68.7% had some type of refractive error, while a higher proportion of females (72.4%) had refractive errors.

A total of 143 (92.8%) students stated they had already consulted an ophthalmologist, of which 76 (53.1%) had had their last consultation less than a year ago, 49 (34.3%) between 1-3 years and 18 (12.6%) more than 3 years ago. Among students with refractive errors, 66 (60.5%) had had a consultation less than a year ago, 39 (35.5) between 1-3 years and only 4 (3.7%) more than 3 years ago.

Regarding the methods of visual correction, as shown in Table 2, most students used eyeglasses (including 79.7% of those with myopia and 60% of those with other refractive errors), sometimes associated with contact lenses. In addition, 10.1% of those with myopia declared they did not use any kind of visual correction, despite being advised to. This figure rose to 26.7% among students with refractive errors other than myopia

As shown in Table 3, of the 154 students, 132 (85.7%) said they had heard of refractive surgery, of which only 65 (49.2%) said they knew how the procedure was performed. Of the students who had heard of it, 95 (72%) had refractive errors. As shown in Figure 1, 23.5% stated that they had been informed about the procedure by their ophthalmologist, followed by 17% who were informed by their relatives. Students with refractive errors were also asked how they would feel about undergoing refractive surgery. 43.2% confirmed they would be willing to undergo the procedure, 38.9% said they would not and the remaining 17.9% did not know or did not answer.



Figure 2 shows that the main reason why the students who did want to have refractive surgery had not undergone the procedure was because the doctor had advised them against it, as mentioned by 30.2% of participants, followed by financial reasons, mentioned by 24.5% of participants.



As shown in figure 3, 74.4% of students who did not want to undergo the procedure claimed this was because of their mild visual impairment. Of those who did not know, the aforementioned argument was also the most common, but it corresponded to 35.5% of answers.



As shown in figure 4, 89 (67.4%) of the students who knew about the procedure expected only a reduction of visual dependence after undergoing refractive surgery (Table 5). A larger percentage of students who wanted to undergo refractive surgery expected greater benefits.



Students with myopia were the most likely to consider undergoing the procedure: 69.8% of them wanted to undergo surgery.

Only 3 students, aged 22, 23 and 33, had already undergone refractive surgery, of which two were male and one was female.

All had had a consultation with an ophthalmologist less than a year ago. All three students had been diagnosed with ametropia between the ages of 6 and 12. Also, both parents of all three students had some kind of refractive error. All three students said they had expected a complete cure before undergoing surgery, and none of them had a current visual impairment. Therefore, they expressed satisfaction with the results. With regard to where they obtained information about the procedure, all three said they knew about it from their ophthalmologist, and even after having undergone the procedure, 1 student (33.3%) said he would like to know more about it.

The aforementioned procedures were carried out in the same year the questionnaire was administered. One was covered by a health insurance plan and the other two were paid for privately. Regarding the level of visual impairment before surgery, two students had between -1.25 and -3.00 dioptres and one an impairment greater than -3 dioptres.The household income for all three students was greater than 15 times the minimum wage.



A total of 109 (70.8%) participants stated they had some kind of refractive error. Myopia was the most common refractive error and was present in 40.4% of participants. This is twice the prevalence found in the general population, which is around 25% according to previous studies(4). The figure found in our study is in agreement with the results of previous studies conducted on medical students, which also found a prevalence twice as high as in the general population(5,6). One example came from a study carried out in the Federal University of Paraná, which found that 48.23% of medical students had myopia(7).

Only 82 (85.7%) study participants had heard about refractive surgery. This rate was considered low given that the subjects were medical students and refractive surgery is one of the most well-known procedures in ophthalmology.This rate was lower than that found by Kara José(3) (92.8%) in a study conducted at ABC's Medical School.

On the other hand only 32.6% of students in our study said they expected a complete cure after undergoing the procedure, a false expectation reported by 69% of students in the study by Kara José(3). We also found that the expectation of a complete cure was higher among subjects who wanted to undergo the procedure.

Other relevant data which emerged from the questionnaires were the quality of information about refractive surgery and its relation to the source of information. A higher percentage of students who knew how the procedure is done and its risks had received information from their ophthalmologist. On the other hand, students who had heard about refractive surgery but did not know how it is done had mostly obtained information from the television and friends. These are seen as poor sources as they only provide limited information, which could explain why this group had only partial knowledge about the subject.

The main reasons why the students who wanted to undergo the procedure had not done so was because they had been advised against it by their doctor or because of financial reasons — 30.2% and 24.5% of participants, respectively. This confirms the results from a similar study conducted at ABC's Medical School, which showed that 39.6% were advised against the procedure by their doctor and 24.7%(3) mentioned financial reasons.

The main reason students gave for not wanting to undergo surgery was their low degree of visual impairment, which was also found in the study conducted at ABC's Medical School(3).

Another relevant observation was that the fear of the procedure or its results was a reason given almost exclusively by students who did not know how the procedure was done. This group also showed the least interest in undergoing surgery.

Only 3 students in the sample had already undergone refractive surgery. This is probably due to the participants young age — 21 years old on average. At this age, eyesight usually has not yet stabilised, a prerequisite for surgery.



Brazilian medical training currently prioritises certain areas of medicine to the detriment of others. Ophthalmology is given little importance on the medical curriculum. This is evident from the fact that although a significant number of students said they knew about the procedure, less than half knew how it was performed. As such, there is a clear lack of knowledge about one of the most commonly used and debated procedures in the field — Lasik is one of the most commonly performed operations in the world. The study participants showed a lack of information about the procedure; considering they are medical students, they should know much more about the topic.

Also, the lack of knowledge about the subject affects the interest of participants in undergoing the procedure, as shown by the considerably higher number of participants who did not want to undergo surgery amongst those who did not know how it was performed, compared to out of those who did know.

The main aim of refractive surgery is to reduce the dependence on correction methods. Interestingly, there was a greater number of students with false expectations amongst those who said they wanted to undergo surgery, compared to those who did not. That is to say, they expect the refractive error to be completely corrected. This situation is far from ideal because patients tend to be more satisfied when they have more realistic expectations about the procedure.

Therefore, the general population, and medical students in particular, needs greater clarification on the matter. This is very important given that in the future, these students will become the professionals who will have to answer the doubts their patients might have about the matter.


Marcelo Rosa Gameiro and Leonardo Thomaz de Aquino Filho.



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Received for publication: 19/6/2012
Accepted for publication: 29/1/2013
Os autores declaram não haver conflitos de interesse



Study conducted at the State University of Londrina (UEL), Londrina/PR, Brazil.



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