![]() For postoperative cataract patients, this means that patients may obtain variable visual quality from day to night because of such HOAs’ variations. Previous researches 10, 11, 12 also showed that pupil size has an effect on HOAs. Therefore, choosing HM patients with posterior staphyloma as subjects for internal HOAs’ research and making it clear about the relationship between certain intraocular structure and the HOAs would be of great importance. The intraocular structures of high-myopic eyes are largely different from those in eyes with normal AL. 9 However, in pseudophakic eyes, original structure of the eyes and intraocular lens (IOLs) are the major determinants of internal HOAs, which further affect the ocular HOAs. In phakic eyes, internal HOAs, as part of the ocular HOAs, derive mainly from crystalline lens as well as other internal optic structure. However, most of the previous studies regarding visual quality of high-myopic eyes were concerned with corneal or ocular HOAs, 7, 8 and little was known about internal HOAs. 5 As the morphological characteristics of posterior staphyloma are now well understood after the application of optical coherence tomography, it is worthy to further look at the relationship between posterior staphyloma and visual quality of the high-myopic eyes. 3 Its definition lacks consensus, which is usually defined with the following features: long axial length (≥26 mm) or refractive error of −6 D or above 4 and pathological fundus changes such as posterior staphyloma, lacquer cracks, and chorioretinal atrophy. High myopia (HM) is a leading cause of visual impairment worldwide 2 and its prevalence continues to increase, especially in Asian populations. It can represent part of the optical errors that lower order aberrations such as defocus and astigmatism cannot explain. Therefore, wavefront aberrations have become an important parameter for evaluating visual quality, 1 among which higher-order aberrations (HOAs) are of great significance. The patient’s demand is not only limited to the improvement in visual acuity, but also better visual quality. Nowadays, cataract surgery has changed from a visual rescue treatment to a refractive procedure. High-myopic pseudophakic eyes with posterior staphyloma had significantly lower internal coma and less coma variations during mydriasis. Statistically significant differences were also found for the variation of modulation transfer functions (MTFs) at frequencies of 15, 30, 45, and 60 cycles/degree between the two groups ( P=0.002, 0.002, 0.004, and 0.010, respectively). After mydriasis, Strehl ratio increased significantly in high-myopic eyes, whereas decreased slightly in normal axial length eyes ( P=0.032 when compared with the variation between the two groups). Statistically significant differences were also found in the variation from 4- to 6-mm pupil sizes for internal coma ( P=0.001), internal third-order aberrations ( P=0.009), internal total HOAs ( P=0.007), and ocular coma aberrations ( P=0.006) between two groups. ResultsĬompared with normal axial length eyes, high-myopic pseudophakic eyes with posterior staphyloma had significantly lower values of internal coma both under 4-mm and 6-mm pupil sizes ( P<0.001 and 0.020), as well as internal total HOAs ( P<0.001) and third-order aberrations at 6-mm pupil size ( P=0.018). At 1 month after phacoemulsification and intraocular lens implantation, ocular and internal HOAs as well as the visual quality data in the two groups were evaluated with KR-1W analyzer before and after mydriasis. Methodsįorty eyes of 40 high-myopic cataract patients with posterior staphyloma and 20 eyes of 20 age-related cataract patients with normal axial length were recruited. To evaluate the effect of pupil size on higher-order aberrations (HOAs) in high-myopic pseudophakic eyes with posterior staphyloma using KR-1W aberrometer.
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