Central corneal thickness and corneal volume changes in eyes with and without pseudoexfoliation after uneventful phacoemulsification

Corneal Clarity and Tomographic Patterns in Pseudoexfoliation Syndrome: A Severity-Based Investigation

PURPOSE

The aim of the study was to investigate the corneal and anterior segment characteristics in pseudoexfoliation syndrome (PXS), depending on the severity of the disease.

MATERIALS AND METHODS

This cross-sectional study was conducted at a tertiary care hospital, in the ophthalmology department, in Turkey. Pseudoexfoliation syndrome group was classified into three groups. Pseudoexfoliative material on the part of the pupillary border was classified as group 1, on the entire pupillary border was classified as group 2, and pseudoexfoliative material on the entire pupillary border and iris surface was classified as group 3. The control group was composed of age and gender-matched individuals who had undergone a completely normal ophthalmologic examination. Scheimpflug tomography was performed to record tomographical data.

RESULTS

The PXS groups 1, 2, and 3, along with the control group, consist of 29, 32, 33, and 42 participants, respectively. There was no significant difference in age-gender distribution between patients and the control group ( P >0.05). Group 3 showed significant differences in central corneal thickness compared with the control group ( P =0.001). In addition, anterior chamber angle was found to be significantly lower in group 3 than the control group ( P <0.001). In corneal densitometry (CD) values, significant increases compared with the control group were observed in groups 2 and 3 across all anterior annuli ( P <0.001). In group 1, significant increases observed in the anterior 6-10 mm and 10-12 mm annuli ( P <0.001). In the middle 6-10 mm annuluses, only group 3 showed a significant increase compared with the control group ( P <0.001). In the posterior 0-2, 2-6, and 6-10 mm annuli, significant increases compared with the control were observed only in groups 2 and 3 ( P =0.001, P =0.001, P <0.001, respectively).

CONCLUSIONS

Corneal densitometry values, even without an increase in intraocular pressure, have a tendency to increase in PXS depending on the severity of the disease. While minimal changes were observed in the middle layer, it was particularly noted that the effects of the disease were more prominent in the peripheral cornea.

Exploring association between pseudoexfoliation syndrome and ocular aging

PURPOSE

Within a population-based follow-up study, to examine the 10-year incidence of pseudoexfoliation syndrome (PEX), possible risk factors for PEX and its association with ocular aging of the cornea, lens and retina.

METHODS

The baseline examination was conducted in 2006 on a random sample of 1,033 adult participants from Kaunas city (Lithuania) population of whom 631 had ophthalmic examination data at attendance of the 10-year follow-up in 2016. Detailed examination of the anterior and posterior segment of the eye was carried out. After diagnostic mydriasis PEX was diagnosed by the presence of typical grayish-white exfoliation material on the anterior capsule surface of the lens. The participants were divided to PEX and non-PEX groups.

RESULTS

PEX prevalence increased from 9.8 to 34.2% from baseline to 10-year follow-up. Nuclear cataract was common both in the PEX group (66.7%) and in those without PEX (72.2%), but this difference did not reach statistically significantly increased risk of developing cataract in those with PEX (OR 1.2; p = 0.61). Central corneal thickness (CCT) was thinner in the PEX group (529 ± 34 μm) and in the oldest group (525 ± 36 μm) (p < 0.001). Compared to baseline, corneal curvature (CC) became flatter in both groups (7.6 ± 0.27 vs 7.7 ± 0.26 mm; p < 0.001) during the follow-up, but the difference did not reach significance between groups. Corneal astigmatism was most commonly with-the-rule in both groups (37 (50.0%) vs 148 (68.5%); p > 0.05). Age, sex and PEX had no influence on age-related macular degeneration distribution.

CONCLUSION

The prevalence of PEX increased significantly with age in our population, with those with PEX having thinner and flatter corneae, but no difference in cataract and age-related macular degeneration characteristics.

Evaluation of Corneal Endothelium after Myopic Laser-Assisted In Situ Keratomileusis (LASIK) with Accelerated Cross-Linking (CXL) in Diabetic Patients

Purpose:

To study the effect of LASIK with accelerated CXL on corneal endothelium in myopic diabetic patients.

Methods:

A prospective comparative interventional case series study on 120 eyes of 60 myopic patients treated with LASIK with accelerated CXL. They were divided into two groups; group A included 60 eyes of diabetic patients, group B included 60 eyes of non-diabetic patients. Corneal endothelium was evaluated by specular microscope preoperatively and after 3 and 6 months postoperatively.

Results:

The endothelial cells density (ECD) showed statistically significant changes after 3 and 6 months postoperatively (p-value <0.001) in group A while group B showed statistically significant changes after 3 months without significant change after 6 months (p-value= 0.103), both groups had improved to near preoperative levels, with no significant differences between them at the end of 6 months follow-up (p-value = 0.219). Regarding pleomorphism, there was a significant change in group A during 6 months follow-up (p-value <0.001) with no significant change in group B (p-value= 0.884), and in comparing both groups, there was a significant change at the end of 6 months follow-up (p-value <0.001). Regarding polymegathism, there was a significant change in group A during 6 months follow-up (p-value <0.001) with no significant change in group B after 3 (p-value= 0.178) and 6 (p-value= 0.866) months follow-up, and in comparing both groups, there was a significant change at the end of 6 months follow-up (p-value <0.001).

Conclusion:

LASIK with accelerated CXL is safe on corneal endothelium in diabetic myopic patients but needs to follow up for a long period.

Simultaneously Monitoring Whole Corneal Injury with Corneal Optical Density and Thickness in Patients Undergoing Cataract Surgery

To pursue the least corneal implication during cataract surgery, this study aimed to monitor corneal wound injury after cataract surgery with a novel method. The prospective cohort study involved thirty-two patients, who were assessed by a Scheimpflug tomography AxL^® (Oculus GmbH, Wetzlar, Germany) via the following two kinds of indices: whole corneal optical density (COD) and corneal thickness (CT), two weeks before and one month after cataract surgery. The results of the COD revealed that corneal annuli 0.0–2.0 mm and 2.0–6.0 mm, and the average and maximal values at the incisional site significantly increased postoperatively. Also, the anterior and central stroma of 0.0–2.0 mm, and all three depths of 2.0–6.0 mm, increased remarkably after the operation. For the CT, all ranges of diameters plus incisional sites showed significant increases postoperatively. Furthermore, we analyzed the differences (delta) of COD and CT between pre- and post-operation, and found significant correlations between the delta of COD and the delta of CT, regarding annuli 0.0–2.0 mm, 2.0–6.0 mm, and 6.0–10.0 mm, but no correlation at the incisional site, with either average density or maximal density, was detected. We concluded that whole COD and CT, especially at the central zones of the cornea (annulus < 6 mm), are both valuable parameters in the assessment of corneal damage post-cataract surgery, and are independent indices at the incisional site.

Comparative Analysis of One-Handed and Two-Handed Coaxial Phacoemulsification with 2.4-mm Clear Corneal Incision

PURPOSE

To compare the efficiency and safety of one-handed and two-handed coaxial phacoemulsification Material and Methods: Patients with cataracts underwent one-handed (one-handed group) or two-handed coaxial phacoemulsification (two-handed group) with a 2.4-mm clear corneal incision. Intraoperative phaco parameters, total surgical time, postoperative visual acuity, surgically induced astigmatism (SIA), corneal volume (CV), central corneal thickness (CCT) and corneal endothelial cell counts/size were compared between the two groups.

RESULTS

Each group comprised 105 eyes. There were no significant differences in the intraoperative phaco parameters and total surgical time between the two groups (all p > 0.05). Visual outcomes were significantly better in the one-handed group than in the two-handed group 1 week postoperatively (all p< 0.05) but not 1 month postoperatively. There was no significant difference in SIA between the two groups 1 week (p = 0.695) or 1 month postoperatively (p = 0.772). CV, CCT and endothelial cell loss were significantly lower in the one-handed group than in the two-handed group 1 week postoperatively (CV: p = 0.004; CCT: p = 0.046; endothelial cell loss: p = 0.021), but the above differences were absent 1 month postoperatively except for endothelial cell loss (endothelial cell loss: p = 0.038).

CONCLUSIONS

Both one-handed and two-handed coaxial phacoemulsification were effective and safe surgical techniques. However, the one-handed technique had the advantages of less trauma to the cornea and better early clinical outcomes than the two-handed technique for cataract patients within nuclear opalescence (NO) 3 grade ≤ 3.

Effect of Proparacaine 0.375%-Sodium Fluorescein 0.25% Eye Drop Mixture and Fluorescein Strip on Anterior Segment Parameters

Purpose

To determine the effect of proparacaine 0.375%-sodium fluorescein 0.25% eye drop mixture and fluorescein strip on anterior segment parameters commonly used in routine ophthalmology practice.

Methods

115 healthy volunteers without any systemic or ocular disease were divided into two groups. 57 volunteers were in the proparacaine 0.375%-sodium fluorescein 0.25% eye drop mixture group, and 58 volunteers were in the fluorescein strip group. Measurements (CCT (central corneal thickness), topographic pupil diameter, AD (aqueous depth), ACV (anterior chamber volume), ICA (iridocorneal angle), LLD (limbus-limbus distance), and CV (corneal volume)) were taken before and at 1, 5, 15, and 30 minutes after application.

Results

59 (51.3%) participants were female, and 56 (48.7%) were male. The mean age of the drop application group was 26.88 ± 8.03, and the mean age of the strip application group was 26.33 ± 7.28. The mean CCT was 556 ± 32 μm before drop application and 569 ± 30 μm in the 1st minute, 560 ± 32 μm in the 5th minute, and 559 ± 31 μm in the 15th minute. The change was statistically significant (p < 0.001, p=0.005, and p=0.013, resp.). Before the strip application, mean CCT was 552 ± 36 μm, while it increased to 556 ± 36 μm at the 1st minute, and this change was statistically significant (p=0.002). The mean CV before dropping was 59.29 ± 3.53 mm³ and 60.62 ± 3.53 mm³ at the 1st minute and 59.66 ± 3.70 mm³ at the 5th minute, which was statistically significant (p < 0.001 and p=0.034). Mean topographic pupil diameters at the 1st, 5th, 15th, and 30th minute after application of drops and strips were not significantly changed compared to the preapplication values in the AD, ACV, ICA, and LLD measurements.

Conclusions

Proparacaine 0.375%-sodium fluorescein 0.25% eye drop mixture and fluorescein strip application lead to a temporary change in CCT and CV of the anterior segment parameters. Anterior segment measurements with the Scheimpflug camera have to be done before topical fluorescein application.