Changes in choroidal and foveal retinal thickness after cataract surgery: Our results.

INTRODUCTION: Cataract surgery is the most common ophthalmic surgical procedure worldwide. In addition, the retina and choroid are the tissues most susceptible to damage during cataract surgery. However, conflicting results have been found about the relationship between choroidal thickness (CT), retinal thickness (RT), and cataract surgery. AIM: To evaluate the changes in CT and foveal retinal thickness (FT) following cataract surgery in standardized conditions. METHODS: Twenty eyes from 20 patients who experienced uneventful cataract surgery and twenty eyes from 20 age- and sex-matched healthy volunteers were recruited in the study. Optical coherence tomography measurements were obtained for 1 day, 1 week, and 1 month postoperatively and compared with the preoperative and control values. The main outcome measure was through the mean change in CT and FT. RESULTS: The FT values did not change throughout the follow-up. A statistically significant increase in CT at the macular (P = 0.003) and temporal 1 mm region (P = 0.04) was observed at 1 week following the surgery. However, it decreased to nearly preoperative values at 1 month postoperatively. CONCLUSION: Although the FT remains stable following uneventful phacoemulsification, the CT changes minimally in the early postoperative period. However, this effect is transient and does not appear to be clinically significant in routine conditions.

Accelerated epithelium-on or accelerated epithelium-off corneal collagen cross-linking: Contralateral comparison study.

PURPOSE: The aim of the study is to compare the accelerated epithelial-on corneal collagen cross-linking (epi-on CXL) and accelerated epithelial-off corneal collagen cross-linking (epi-off CXL) in terms of clinical and confocal microscopy results. MATERIALS AND METHODS: Forty-two eyes of 21 patients with progressive keratoconus and simultaneously undergoing accelerated epi-on CXL in one eye and accelerated epi-off CXL in other eye were evaluated. Uncorrected visual acuity (UCVA) and best-corrected visual acuity (BCVA) with spectacle in logMAR and topographic findings (mean keratometry [K mean] and maximum keratometry [Kmax]) were recorded at 1, 3, 6, 12, 18, 24, and 30 months. Eyes were compared in terms of subjective pain scores after the procedures. Furthermore, anterior segment optical coherence tomography and confocal microscopy were performed at 1 month. RESULTS: Kmean and Kmax were less than baseline in both the groups; however, the reduction was significantly higher in epi-off CXL than epi-on CXL eyes at 18 and 30 months. The UCVA and BCVA increased approximately 1 Snellen line at the end of mean follow-up in epi-off CXL and in epi-on CXL. Stromal demarcation line for epi-off CXL is 276.4 ± 58.9 while 148.3 ± 24.8 for epi-on CXL (P = 0.001). Furthermore, subepithelial nerves were observed in any eye in epi-off CXL; however, subepithelial nerves were observed in 12 eyes (80%), in epi-on CXL (P = 0.01). CONCLUSION: Both techniques were able to stop progression; however, in contrast to expectations, the pain was felt more in epi-on CXL than epi-off CXL.

The Relationship Between Macular Cyst Formation and Ischemia in Diabetic Macular Edema

Objectives: To evaluate the relationship between cyst characteristics and macular and peripheral ischemia in diabetic macular edema (DME). Materials and Methods: We retrospectively reviewed eyes with DME and included those with clinically significant macular edema as defined by ETDRS (Early Treatment Diabetic Retinopathy Study) and cystoid spaces in optical coherence tomography scans in this study. Central subfield thickness (CSFT), horizontal and vertical diameters of the largest cyst, cyst area, and the remaining retinal thickness outside the cyst were determined. The presence and number of hyperreflective foci in the cyst wall and the internal reflectivity of the cyst were analyzed. Outer retinal damage was graded. Fluorescein angiography was used to determine the areas of macular and peripheral ischemia, which were graded as mild or severe. Correlations between macular and peripheral ischemia and cyst-related measurements and structural changes in the retina were evaluated. Results: This retrospective study included 250 eyes of 186 patients with DME. Mean CSFT was significantly greater in eyes with macular ischemia (510.4±144.7 µm) compared to eyes without macular ischemia (452.1±114.6 µm) (p=0.001). Horizontal and vertical diameter of the largest cyst increased with the presence and severity of macular ischemia (p=0.045 and p=0.016, respectively). Remaining retinal thickness increased with the presence and severity of peripheral ischemia (p=0.009). There was a statistically significant relationship between the number of the hyperreflective foci in the cyst wall and internal reflectivity of the cyst (p=0.007). Patients with greater CSFT had a 1.04-times higher odds of having macular ischemia and 0.25-times higher odds of having outer retinal damage. Conclusion: The likelihood of macular ischemia increases with larger cyst diameter, CSFT, and extent of outer retinal damage. Thickness of the noncystic area is increased in the presence of peripheral ischemia.

Retinal Neural and Vascular Structure in Isolated Growth Hormone Deficiency Children and Evaluation of Growth Hormone Treatment Effect

OBJECTIVE: To evaluate neural and vascular retinal morphology of children with isolated growth hormone deficiency (GHD) and to determine any retinal changes due to GH treatment. METHODS: Twenty-eight children with isolated GHD and 53 age-, gender- and body mass index-matched healthy volunteers were enrolled in this prospective study. The retinal nerve fibre layer (RNFL) and macular thickness (MT) were measured, as well as intraocular pressure (IOP). The number of retinal vascular branching points were calculated. Effect of GH treatment on the retina and IOP was evaluated after one year of treatment. Measurements were also made in the control group at baseline and following the initial examination. Pre- and post-treatment changes were compared. The findings were also compared with those of the controls. The correlation between ocular dimensions and insulin-like growth factor-I (IGF-1) levels were also analysed. RESULTS: The number of branching points was significantly lower in GHD patients as compared with control subjects (15.11±2.67 and 19.70±3.37, respectively, p=0.05 for all comparisons). No statistically significant differences were found in mean RNFL, MT and IOP values between GHD patients and control subjects. GH treatment did not create any significant changes in the retinal vascularization or other retinal neural parameters and IOP either within the patient group or when compared with the control group. No correlations were observed between ocular dimensions and IGF-1 levels. CONCLUSION: Our findings suggest that isolated GHD may lead to decreased retinal vascularization. However, retinal neural growth and differentiation were not affected by GHD. These findings may be related to the fetal development process of pituitary somatotropic cells and the retina. Additionally, GH treatment did not cause any changes in retinal neural and vascular tissues.

Safety of Polyacrylamide 1.5% Left in Anterior Chamber in Combined Phacoemulsification and Pars Plana Vitrectomy Surgery.

PURPOSE: To evaluate safety, efficacy and postoperative characteristics of polyacrylamide 1.5% ophthalmic viscosurgical device (OVD) left in anterior chamber during and at the end of combined phacoemulsification and pars plana vitrectomy surgery. MATERIALS AND METHODS: This prospective study comprised 20 eyes that received combined phacoemulsification and pars plana vitrectomy performed by the same surgeon. Polyacrylamide 1.5% was left in anterior chamber at the end of the surgery. Preoperative and postoperative examinations (4, 12 and 24 hours; 14 days; 1 and 3 months) included measurement of intraocular pressure (IOP), central corneal thickness (CCT), endothelial cell density and assessment of any ocular adverse reactions. RESULTS: Four of the 20 patients (20%) showed increased IOP at hours postoperatively and needed medical treatment for IOP control. There was no significant difference in IOP between the preoperative visit and postoperative 3 months (p > 0.05). CCT measurements were similar between preoperative and postoperative visits (p > 0.05). A mean endothelial cell density loss of 6.7% was observed at postoperative day 14, however there was no change after this visit. CONCLUSION: Polyacrylamide 1.5% is safe, well-tolerated and protective in eyes undergoing combined phacoemulsification and pars plana vitrectomy.

Microbiologic Examination of Bandage Contact Lenses Used after Corneal Collagen Cross-linking Treatment.

PURPOSE: To investigate the agents of bacterial contamination of contact lenses after corneal collagen cross-linking (CCL), and to present the possible changes of ocular flora after riboflavin/ultraviolet A. METHODS: Seventy-two contact lenses of patients who underwent CCL and 41 contact lenses of patients who underwent photorefractive keratectomy (PRK) as control group were enrolled to the study. After 48 h of incubation, broth culture media was transferred to plates. Samples were accepted as positive if one or more colony-forming units were shown. RESULTS: There were positive cultures in 12 (16.7%) contact lenses in the CCL group and 5 (12.2%) had positive cultures in PRK group. Coagulase-negative staphlycocci (CNS) were the most frequent microorganism. Alpha hemolytic streptococci and Diphteroid spp. were the other isolated microorganisms. CONCLUSIONS: Bacterial colonization can occur during and early after the CCL procedure in epithelial healing. To prevent corneal infections after the treatment, prophylactic antibiotics should be prescribed.

Macular choroidal thickness measurements in patients with obstructive sleep apnea syndrome.

PURPOSE: The purpose of this study is to assess macular choroidal thickness measurements in patients with different severities of obstructive sleep apnea syndrome (OSAS) versus normal controls by using enhanced depth imaging optical coherence tomography (EDI-OCT). DESIGN: This paper is a descriptive study. MATERIALS AND METHODS: In this prospective study, the macular area of 74 patients with OSAS and 33 controls were evaluated. All subjects underwent complete ophthalmic examination and macular choroidal thickness (CT) measurements by enhanced depth imaging method of the Spectralis optical coherence tomography system. Choroidal thickness (CT) was measured at the fovea and at 1,000-µm intervals from the foveal center in both temporal and nasal directions by two masked observers. RESULTS: The mean age was not significantly different between patients with OSAS and controls. Patients were grouped as mild (n = 15), moderate (n = 28), and severe (n = 31) according to apnea-hypopnea index (AHI) scores. The mean subfoveal choroidal thickness (SFCT) was 338.0 ± 85.2 µm in the control group versus 351.3 ± 90, 307.8 ± 65.5, and 325.4 ± 110.2 µm in mild, moderate, and severe groups, respectively (p = 0.416). There was no significant correlation between the severity of OSAS and choroidal thickness. CONCLUSIONS: The patients with OSAS seem to protect the choroidal thickness despite hypoxia. The role of OSAS in the pathophysiology of choroidal blood flow and choroidal structure needs further investigation.

Reproducibility of choroidal thickness measurements in healthy Turkish subjects.

PURPOSE: To assess intraobserver and interobserver reproducibility of the measurement of choroidal thickness by using enhanced depth imaging optical coherence tomography (EDI-OCT). METHODS: A prospective, cross-sectional study was performed at Gazi University Ophthalmology Department. The macular areas of the right eyes of 110 healthy volunteers with no ophthalmic or systemic disease were recruited. Choroidal thickness was measured at the fovea and at 1000-µm intervals from the foveal center in both temporal and nasal directions. Each examiner measured choroidal thickness 30 days after the first measurement to assess intraobserver variability. Interobserver and intraobserver reproducibility were described by intraclass correlation coefficient (ICC) and coefficient of variation (CV). RESULTS: The mean age was 44.0 ± 14.7 years (range 18-70 years). The mean choroidal thickness at the fovea was 315.5 ± 78.6. All the parameters evaluated were highly reproducible. Intraobserver CV of choroidal thickness measurements ranged from 24.76% to 35.74%, and the CV of subfoveal choroidal thickness was 24.92. The intraobserver and interobserver intraclass correlation coefficient was greater than 0.90 for all the parameters. Repeatability was slightly better at locations not exceeding 400 µm. CONCLUSIONS: Choroidal thickness measurements obtained by EDI-OCT showed good repeatability for healthy Turkish subjects; EDI-OCT examinations of choroid are reliable in healthy eyes.