Introduction

Pseudoexfoliation is a gray-white, fibrogranular material that accumulates in the anterior lens surface, pupillary edge, iris and angle in the eye, and in the walls of vessels and tissues in the body (1-3).

An area where pseudoexfoliation accumulates in the eye is the corneal endothelial region. The pseudoexfoliation material deposited in this region causes alterations firstly in the functions of corneal endothelial cells, and changes the shape and number in later periods (4). In addition, pseudoexfoliation material deposited on the surface of the cornea may cause corneal curvature changes in cases with increased intraocular pressure (5). The other accumulation area of exfoliative material in the eye is the anterior chamber angle and lens zonules (4,6,7). The material deposited at the anterior chamber angle can cause resistance to the passage of the aqueous humor to the trabecular network, causing open-angle glaucoma (8). Exfoliative material accumulated in the zonules may damage the lens zonules and cause the development of zonular weakness (9). This situation may cause many complications such as loss of zonules, development of aphakia and loss of vitreous in cataract surgery (10,11). In the event that exfoliative material accumulates in the iris, pupillary dilatation occurs less during surgery and an increase in the complications of cataract surgery can be observed (12,13). Another site of pseudoexfoliation in the eye is the lens anterior capsule (14).

The primary accumulation of pseudoexfoliation material outside the eye is the arterial vessel walls. As a result of this accumulation, the probability of cardiovascular and cerebrovascular diseases increases (15,16).

Methods

Ethics committee approval was obtained from Pamukkale University Faculty of Medicine Medical Ethics Committee (decision no: 05, date: 05.03.2019). The study was conducted in accordance with the Declaration of Helsinki. Written and oral consent was obtained from the patients included in the study and their data were evaluated within the scope of the study.

Patients who presented to our ophthalmology outpatient clinic with low vision complaints between 01.03.2016 and 01.04.2019 and in whom the cause of vision loss was due to cataract were included in our study. Age, gender, preoperative maximum dilated pupillary diameters, preoperative and postoperative visual acuities, anterior chamber depths and intraocular pressures were recorded. Patients with eye disease other than pseudoexfoliation and cataract, patients with zonular dialysis, and patients with previous ocular trauma and surgery were not included in the study.

Anterior chamber depth measurements were performed before and one month after the surgery with the A-Scan ultrasonography under dim light when the pupil was in its natural state. Dilated pupillary measurements of all patients before and one month after the surgery with biomicroscope following 30 minutes after instillation with one drop of tropicamide (Tropamid 1%, Bilim), cyclopentalate hydrochloride (Cycloplegine 1%, Abdi İbrahim) and phenylephrine hydrochloride (Mydfrin 2.5%, Alcon) at intervals of 10 minutes. Visual acuity and intraocular pressure levels of all patients were measured before and one month after the surgery. Visual acuity level was recorded according to Snellen chart and intraocular pressure level was recorded according to applanation tonometer. All eyes were operated by the same surgeon with experience of over 1000 phacoemulsification surgeries with the same microscope, instruments and surgical instruments. As a surgical method, divide and eat method was used for the nucleus removal in all eyes. In the cases whose posterior capsule integrity was impaired during surgery, vitreous viscoelastic material was removed and the remaining nucleus and cortex were removed by aspiration. In these cases, a 3-part lens was implanted in the sulcus. At the end of the operation, corneoscleral sutures with 10/0 nylon sutures were placed in the patients with posterior capsule opening in the area near the main entrance. The side inlets were inflated with balanced salt solution and the operation was terminated.

Patients were divided into two groups as maximum pupillary dilatation diameter of above or below 5 mm. Preoperative and postoperative anterior chamber depths, visual acuity levels and intraocular pressures and intraoperative complications of the eyes in both groups were recorded.

Statistical Analysis

Statistical analysis was performed using SPSS 25.00 for Windows (SPSS Inc., Chicago, Illinois, USA) software using a paired t-test. Descriptive statistics were given as numbers and percentages for categorical variables. Pearson tests were performed for normally-distributed variables and Spearman tests were used for non-normally-distributed variables. P<0.005 was considered statistically significant.

Results

Sixty eyes of 60 patients, including 31 male (51.7%) and 29 female (48.3%) patients, with a mean age of 70.2±7.1 (range: 57-82) years, were included. Nineteen (31.7%) patients had hypertension. There was no history of diabetes mellitus and alpha-blocker drug use in the patients included in the study. Patients with pupillary diameter above 5 mm were included in group 1, and those below 5 mm were included in group 2. The reference pupillary diameters for grouping were made according to the narrow and normal pupillary width specified in the referenced studies (17-19). Group 1 included 30 eyes of 30 patients, 15 men (50%) and 15 women (50%), with a mean age of 69.3±6.9 (range: 58-82) years and group 2 included 30 eyes of 30 patients, 16 men (53.3%) and 14 women (46.7%), with a mean age of 71.2±7.2 (range: 57-79) years. There was no statistically significant difference between two groups in terms of mean age, gender, hypertension, development of floppy iris syndrome, complications, corneoscleral suturing, preoperative and postoperative visual acuity, intraocular pressure and anterior chamber depths (p=0.304, p=0.508 for male, p=0.509 for female, p=0.478, p=0.500, p=0.447, p=0.500, p=0.304, p=0.904, p=0.644, p=0.025, p=0.437, p=0.150, respectively) (Table 1).

Visual acuity, intraocular pressure and anterior chamber depths were evaluated in both groups before and after surgery. Visual acuity and anterior chamber depth were significantly increased in both groups (p=0.000 and p=0.000 for group 1 and p=0.000 and p=0.000 for group 2, respectively), and intraocular pressure decreased significantly (p=0.000 for group 1 and p=0.013 for group 2) (Table 2).

Floppy iris syndrome developed in three eyes (10%) in group 1 and in one eye (3.3%) in group 2. Posterior capsule integrity was observed to be impaired in four eyes (13.3%) in group 1 and in one eye (3.3%) in group 2. In these five eyes, the nucleus material was not dislocated to the vitreous and the intraocular lens was implanted into the sulcus. Regarding eyes with impaired posterior capsule integrity, corneoscleral sutures were placed in three eyes in group 1 and in one eye in group 2. No statistically significant difference was found between two groups regarding the development of floppy iris syndrome and complications and corneoscleral suturing (p=0.500, p=0447, p=0.500, respectively).

Discussion

Cataract surgery is a necessary method to increase vision in patients with low vision due to cataract (20,21). In pseudoexfoliation cases, cataract causes a decrease in vision and surgical intervention is necessary to increase vision (22,23). Many studies have shown that pupillary dilatation in eyes with pseudoexfoliation is insufficient (24,25). In our study, 30 eyes with preoperative insufficient pupillary dilatation were evaluated. It has also been reported in many studies that the complications that can be observed in cataract surgery may increase in eyes with pseudoexfoliation. The reason for the increase in complications was reported to be insufficient pupillary dilatation and accompanying zonular damage to pseudoexfoliation (12,26). It has also been shown in some studies that the use of capsular tension ring and iris hook during cataract surgery is higher in these eyes than in normal eyes (27-29).

The rate of deterioration of posterior capsule integrity during cataract surgery in the general population was reported as 1.9% by Chakrabarti and Singh (30), as 0.68 by Chen et al. (31) and as 7.9% by Zare et al. (32). In our study, posterior capsule integrity was impaired during surgery in five eyes, including four eyes in group 1 and one eye in group 2. Thanigasalam et al. (33) reported that the incidence of posterior capsule rupture in eyes with pseudoexfoliation was 2.833 times higher than normal eyes. The incidence of posterior capsule rupture observed in our study was found to be 8.3%. This result seems to be compatible with the results of other studies. In studies evaluating populations that did not use any medication and had no additional disease, the rate of development of floppy iris syndrome was reported as 0.018% by Goyal et al. (34) and as 1.18% by Özer et al. (35). The rate of development of floppy iris syndrome in general populations was stated as 9.09% by Kaczmarek et al. (36) and as 4.1% by Neff et al. (37). Tzamalis et al. (38) reported the rate of development of floppy iris syndrome in the general population as 1.29% in women and 5.17% in men. In the literature, there is no study on the rate of development of floppy iris syndrome in patients with pseudoexfoliation. In our study, this rate was found to be 6.6%. This rate was found to be higher than that of Goyal et al. (34), Özer et al. (35), Neff et al. (37), and Tzamalis et al. (38)

Increased visual acuity after cataract surgery has been shown in many studies (39-41). In our study, the postoperative visual acuity level was found to be significantly increased compared to the preoperative visual acuity level. Various studies have shown that postoperative intraocular pressure is lower than preoperative values ​​after cataract surgery (42-44). In our study, intraocular pressure values ​​measured postoperatively were found to be statistically lower than preoperative intraocular pressure values. Several studies have shown that anterior chamber depth is increased after cataract surgery in eyes with and without pseudoexfoliation (45-48). In our study, anterior chamber depth was increased after cataract surgery similar to other studies.

Conclusion

There is an increased risk of complications in cataract surgeries in eyes with pseudoexfoliation. Increased surgical risk in cases where pupillary dilatation is insufficient has been shown to increase in many studies, but this risk increase can be reduced by increasing surgical experience.

Ethics Committee Approval: Ethics committee approval was obtained from Pamukkale University Faculty of Medicine Medical Ethics Committee (decision no: 05, date: 05.03.2019).

Informed Consent: Written and oral consent was obtained from the patients included in the study.

Peer-review: Externally peer-reviewed.

Author Contributions: Surgical and Medical Practices - M.S.A.; Concept - M.S.A., E.Ü.; Design - M.S.A.; S.Z.; Data Collection and/or Processing - M.S.A.; Analysis and/or Interpretation - M.S.A.; Literature Search - M.S.A.; Writing Manuscript - M.S.A.

Conflict of Interest: No conflict of interest was declared by the authors.

Financial Disclosure: The authors declared that this study received no financial support.