Evaluation of retinal vascular structure after epiretinal membrane surgery by optical coherence tomography angiography.

PURPOSE: To evaluate the retinal vascular structure before and after the epiretinal membrane (ERM) surgery by optical coherence tomography angiography (OCTA). METHODS: Twenty-two eyes with ERM (study eyes) had been evaluated by OCTA for superficial capillary plexus (SCP) and deep capillary plexus (DCP) vessel density (VD) at foveal and parafoveal regions and foveal avascular zone (FAZ) before and after ERM removal surgery. Twenty-two fellow eyes were selected as control group. RESULTS: Preoperative VD of SCP and DCP were significantly lower in ERM eyes than in controls in both foveal and parafoveal areas (p < 0.05, for all). The difference regressed in SCP (fovea: 18.04 ± 3.1 vs 19.98 ± 18 p = 0.002 and parafovea: 47.33 ± 3.54 vs 49.71 ± 28 p = 0.001), but persisted in DCP (fovea: 17.25 ± 3.52 vs 17.57 ± 4.01 p = 0.856 and parafovea: 50.12 ± 4.35 vs 50.93 ± 3.24 p = 0.791) in study eyes, postoperatively. Superficial and deep FAZ areas were significantly smaller in study eyes than controls. Postoperatively, superficial FAZ area enlarged (0.288 ± 0.10 vs 0.307 ± 0.08 p = 0.012), whereas deep FAZ area did not (0.324 ± 0.09 vs 0.338 ± 0.07 p = 0.435). FAZ area was correlated with the best-corrected visual acuity in ERM eyes. CONCLUSION: Vascular damage in SCP and DCP was demonstrated by OCTA in eyes with ERM. ERM removal surgery mainly improves superficial changes caused by ERM. Changes in deep retinal flow may be associated with visual outcomes after ERM removal surgery.

INTRAVITREAL DEXAMETHASONE IMPLANT IN RETINITIS PIGMENTOSA-RELATED CYSTOID MACULAR EDEMA.

PURPOSE: To report the clinical outcome after intravitreal dexamethasone implant in patients with retinitis pigmentosa and cystoid macular edema. METHODS: Multicenter retrospective case series of eyes with retinitis pigmentosa and cystoid macular edema that underwent intravitreal dexamethasone implant. Primary outcome measures were best-corrected visual acuity in LogMAR and central macular thickness. Statistical analyses used two-tailed comparison with Wilcoxon signed-rank test. RESULTS: There were a total of 45 eyes from 34 patients with a mean age of 32.7 years (range 16-57) and mean follow-up of 15.5 ± 13.0 months. At Month 3 after the first injection, mean initial best-corrected visual acuity improved from 0.61 ± 0.38 (20/81) to 0.37 ± 0.16 (20/47) (P = 0.012), whereas mean central macular thickness (µm) decreased from 506 ± 288 µm to 311.7 ± 71.6 µm (P < 0.001) and mean intraocular pressure increased from 15.7 ± 2.3 mmHg to 19.8 ± 11.0 mmHg (P = 0.01). Fourteen eyes had multiple injections (1-7 reinjections) at a mean interval of 6 months. Treatment effect was durable with multiple injections, but with seven eyes developing visually significant cataracts. CONCLUSION: Best-corrected visual acuity improved up to 4 months in around half of the eyes. Eyes that benefited the most were pseudophakic, steroid nonresponsive, with large initial central macular thickness, and profuse fluorescein dye leakage.

The effect of caffeine on choroidal thickness in young healthy subjects.

BACKGROUND: To investigate the effect of oral caffeine intake on choroidal thickness using optical coherence tomography (OCT). METHODS: Eighteen otherwise healthy caffeine users and 18 controls were enrolled. All participants underwent OCT scanning with high-speed and resolution spectral-domain OCT device (3D OCT 2000, Topcon, Japan) at baseline, and 1 and 3 h following 200-mg oral caffeine intake in the study and after oral placebo in the control group. The measurements were taken in the morning (10-12 am) to avoid diurnal fluctuation. RESULTS: The median choroidal thickness at the fovea prior to oral caffeine intake was 337.00 (IQR 83.75) µm, which decreased to 311.00 (IQR 79.25) µm at 1 h and 311.00 (IQR 75.00) µm at 3 h following oral caffeine intake (p = 0.001, 0.002, respectively). The median choroidal thickness was also significantly decreased following oral caffeine intake at other five extrafoveal points (p < 0.05 for all). The difference in choroidal thickness was not statistically significant between 1 and 3 h of caffeine intake at all six points. In the control group, the median baseline choroidal thickness at the fovea was 330.00 (IQR 88.75) µm, which was 330.50 (IQR 80.75) µm at 1 h and 330.50 (IQR 90.75) µm at 3 h (p = 0.552, 0.704, respectively). CONCLUSIONS: Caffeine causes a significant decrease in choroidal thickness following oral intake. This decrease might be a result of reduced ocular blood flow due to its vasoconstrictive effect.

Choroidal thickness changes in patients with pseudoexfoliation syndrome.

To evaluate the choroidal thickness using spectral-domain optical coherence tomography (OCT) in patients with pseudoexfoliation syndrome (PXS) and to compare them with healthy controls. This observational comparative study consisted of 35 PXS patients and 35 age- and sex-matched control cases. The control cases had neither systemic nor ocular disease. All 70 patients underwent a complete ophthalmic examination as well as choroidal thickness measurement using a high speed and high resolution SD-OCT device (Topcon 3D OCT-2000, Japan). There was no significant difference with respect to mean refractive error and intraocular pressure measurement between patients with PXS and controls (p = 0.237 and 0.433, respectively). The mean choroidal thickness was found as 206.6 ± 37.6 µm in the PXS group and 215.9 ± 47.3 µm in controls, respectively. The mean choroidal thickness was not significant between the PXS patients and the control cases (p = 0.362). Although PXS patients had lower mean choroidal thickness than controls, our results did not reach any statistical significance.

Subconjunctival bevacizumab in the impending recurrent pterygia.

The aim of this study is to evaluate the efficacy and safety of subconjunctival bevacizumab injection(s) in the treatment of impending recurrent pterygia. Twenty-three eyes of 23 patients who developed impending recurrence after pterygium surgery with conjunctival autografting and were treated with subconjunctival bevacizumab injection(s) (2.5 mg/0.1 mL) were included in the study. Anterior segment photographs were taken prior to and at 1 week, 1, 3 and 6 months after the injection, and at the end of the follow-up period. Image analysis was performed using an image processing and analysis software program. Recurrence rate and complications were recorded. The mean age and follow-up time of the patients were 51.2 ± 6.2 (31-60 years) and 16.8 ± 3.1 (12-22 months), respectively. The average number of injections was 2 ± 0.78 (1-3). Sixteen eyes required re-injection (two injections in nine eyes, three injections in seven eyes), due to progression of vascularization. There were significant differences between size percentage of lesions before injection and at 1 week, 1, 3 and 6 months after the injection (p < 0.05 for all). Corneal recurrence developed in only one patient and no ocular or systemic side-effects of bevacizumab were observed. Repeated injections of bevacizumab may help to prevent the high recurrence rate of residual impending pterygium, due to its adjuvant role in decreasing lesion size, especially in the first year after surgery.

Topical and subconjunctival bevacizumab for corneal neovascularization in an experimental rat model.

AIMS: To evaluate and compare the inhibitory effects of topical and subconjunctival bevacizumab on corneal neovascularization in a rat model. METHODS: Twenty corneas of 20 rats were chemically cauterized with silver nitrate sticks. Animals were randomized into four groups: a control group that received only topical artificial tear drops twice daily, a subconjunctival injection group that received 1.25 mg (0.05 ml) of bevacizumab on the 1st, 4th, and 7th day, and two topical bevacizumab groups that received instillation of 4 or 12.5 mg/ml bevacizumab twice daily. Digital photographs of the cornea were taken and analyzed using an image analysis software program. On the 10th day, corneas were excised and examined histologically. RESULTS: The mean percentage of the vascularized corneal area (%) in the control group was 63.32 ± 13.10 (mean ± SD), compared with 30.22 ± 15.73 in the subconjunctival injection group, 26.76 ± 10.23 in the 4-mg/ml topical group, and 25.52 ± 12.45 in the 12.5-mg/ml group. The differences between the control and each treatment group were significant (all p < 0.01). Further, histological examination revealed that each treatment group had fewer vessels than the control group (all p < 0.01). CONCLUSIONS: Both subconjunctival injection and topical use of bevacizumab are effective and safe in controlling corneal neovascularization.

Subretinal Coapplication of Tissue Plasminogen Activator and Bevacizumab with Concurrent Pneumatic Displacement for Submacular Hemorrhages Secondary to Neovascular Age-Related Macular Degeneration.

Objectives: To evaluate the functional and morphological outcomes of vitrectomy in combination with intravitreal 5% C3F8 tamponade and subretinal injections of tissue plasminogen activator (tPA) and anti-vascular endothelial growth factor (anti-VEGF) in patients with submacular hemorrhage (SMH) and to investigate the preoperative prognostic factors. Materials and Methods: This retrospective study included 30 patients (16 women, 14 men) diagnosed with SMH secondary to neovascular age-related macular degeneration (AMD). Preoperative SMH thickness and area, ellipsoid zone integrity, and postoperative reduction in the amount of subfoveal blood on optical coherence tomography and fundus photographs were assessed. Furthermore, visual acuity (VA), hemorrhage duration, and the need for additional intravitreal anti-VEGF injections were recorded. Results: The patients' mean age was 73.33±8.23 years. Mean VA improved from logMAR 2.11±0.84 at baseline to logMAR 1.32±0.91, 0.94±0.66, 1.13±0.84, and 1.00±0.70 at postoperative month 1, 2, 3, and 6, respectively. A significant negative correlation was found between hemorrhage duration and postoperative VA at month 2 (p=0.005), month 3 (p=0.019), and month 6 (p=0.012). The mean preoperative SMH duration was significantly shorter in patients who achieved total resolution of the hemorrhage compared with the subtotal resolution group (p<0.001). The mean SMH area was smaller in the patients with continuous ellipsoid zone. Conclusion: Vitrectomy and submacular tPA and anti-VEGF injections with concurrent C3F8 tamponade appears to provide adequate displacement of the hemorrhage, resulting in significant VA improvement in patients with hemorrhagic neovascular AMD. Timing of the surgery appears to be the most important factor determining the final VA.

Successful treatment of necrotizing scleritis after conjunctival autografting for pterygium with amniotic membrane transplantation.

PURPOSE: To report a case of necrotizing scleritis after pterygium surgery with conjunctival autografting (CA) and intraoperative Mitomycin C (MMC) and its treatment with amniotic membrane transplantation (AMT) and systemic steroid. METHODS: A 41-year-old woman who had recurrent nasal pterygium underwent pterygium excision with CA and intraoperative MMC. Two weeks after surgery, graft necrosis and necrotizing scleritis associated with severe pain and irritation were observed on her operated eye. RESULTS: Pulse steroid treatment (intravenous 1 g methylprednisolone for 3 days) was initiated and AMT was performed for ocular surface reconstruction. Over the next 2 weeks, the graft vascularization was complete and there was no complication which required further treatment. CONCLUSIONS: Necrotizing scleritis is a rare complication of CA with MMC. Systemic steroid therapy is necessary for subsiding ocular inflammation and AMT can be performed for ocular surface reconstruction.

Intraocular lens tilt and decentration after Nd:YAG laser posterior capsulotomy: Femtosecond laser capsulorhexis versus manual capsulorhexis.

PURPOSE: To compare intraocular lens (IOL) tilt and decentration after Nd:YAG laser posterior capsulotomy in eyes that had femtosecond laser-assisted capsulotomy versus manual capsulorhexis. SETTING: Ekol Eye Hospital, Izmir, Turkey. DESIGN: Retrospective case series. METHODS: Intraocular lens decentration and angle of tilt were measured using a Scheimpflug camera before and 1 month after Nd:YAG capsulotomy. RESULTS: Eighteen eyes had a femtosecond laser-assisted capsulotomy and 25 eyes a manual capsulorhexis. The mean age was 58.2 years ± 10.2 (SD) (range 44 to 69 years) and 60.6 ± 8.3 years (range 45 to 70 years), respectively. Before capsulotomy, the angle of tilt and decentration at both meridians did not differ significantly between the 2 groups (P > .05). After capsulotomy, the angle of tilt was significantly decreased in both groups (femtosecond: vertical 1.5 degrees and horizontal 1.2 degrees; manual: vertical 1.1 degrees and horizontal) and decentration was significantly increased (femtosecond: vertical 0.085 mm and horizontal 0.096 mm; manual: vertical 0.2 mm and horizontal 0.2 mm) at both meridians (P < .05). After capsulotomy, all tilt and decentration parameters were significantly different between the 2 groups (P < .05) except decentration on the horizontal meridian (P = .669). CONCLUSIONS: Nd:YAG posterior capsulotomy performed after femtosecond laser-assisted capsulotomy resulted in better mechanical stability of the IOL. This suggests that a femtosecond laser-created capsulotomy better maintains a proper IOL position. Although the differences were statistically significant, the tilt and decentration values were small and might not be clinically significant.

The Effect of Nicotine on Macular Microcirculation in Healthy Subjects.

BACKGROUND AND OBJECTIVE: To evaluate the acute effects of nicotine on macular microvasculature by optical coherence tomography angiography (OCTA). PATIENTS AND METHODS: Non-smokers who were administered 4 mg nicotine gum (study group) or placebo gum (control group) were enrolled, 18 individuals in each group. All participants underwent OCTA at baseline and 1 hour after gum chewing. Macular flow area, macular vessel density, foveal avascular zone area, central foveal thickness, and subfoveal choroidal thickness were analyzed. RESULTS: Macular flow area, vessel density, and subfoveal choroidal thickness decreased in the nicotine group (P < .05). No statistically significant difference observed in central foveal thickness, when compared with baseline measurement (P > .05). CONCLUSIONS: Nicotine causes a significant decrease in macular microcirculation. Deterioration of macular microcirculation can be quantitatively detected by OCTA noninvasively. [Ophthalmic Surg Lasers Imaging Retina. 2019;50:691-700.].

Unmeasurable small size superficial and deep foveal avascular zone in nanophthalmos: the Collaborative Nanophthalmos OCTA Study.

AIM: To study the macular structure and vasculature in consecutive nanophthalmic eyes using optical coherence tomography angiography. METHODS: This is a prospective, multicentre, cross-sectional study of patients with nanophthalmos (one or both eyes). The superficial and deep foveal avascular zones (FAZ) were measured both manually and with the machine's built-in automated measurement tool. Correlations between best corrected visual acuity (BCVA), central macular thickness (CMT) and subfoveolar choroidal thickness (SFCT) were calculated. RESULTS: Sixty-five eyes of 35 subjects (16 men and 19 women) with a mean age of 37.4 years were analysed. The mean±SD of refractive error was 14.3±3.2 dioptres, axial length was 16.4±1.6 mm, CMT was 410.2±128.3 µm and SFCT was 450.1±108.3 µm. FAZ was unmeasurable small size in both the superficial and deep capillary plexus in all eyes, along with tortuosity of the superficial foveal capillaries and large vessels. Foveal folds were present in 29 eyes. Disc drusen was detected in 27 eyes and was absent in 31 eyes, while fundus autofluorescence was positive in 17 and negative in 24 eyes. BCVA varied from 20/20 to 20/800, with a mean of 20/76. Using Spearman's correlation, logarithm of the minimum angle of resolution BCVA correlated negatively with axial length (r=-0.30; p=0.015). CONCLUSIONS: FAZ attenuation, capillary tortuosity, foveal folds and thickened subfoveal choroid characterise the nanophthalmic macula. These findings may result from a redundant retina and the absence of apoptotic foveolar retraction because of developmental arrest of the optic vesicle after closure of the embryonic fissure.

Retinal detachment in albinism.

PURPOSE: To report the visual and anatomic outcomes of albino retinal detachment (ARD) repair. METHODS: Collaborative retrospective analysis of ARD. Outcome measures were number of surgical interventions, final retinal reattachment, and best corrected visual acuity (BCVA) at last follow-up. RESULTS: Seventeen eyes of 16 patients (12 males; mean age =37.8 years) had the following complications at presentation: macula off (14), total (7) or inferior detachment (5), proliferative vitreoretinopathy (5), detectable break (16), lattice (5), horseshoe tears (9), and giant tear or dialysis (4). Mean number of interventions was 1.8 (range =1-5) and included cryopexy (15) with scleral buckle (11), and/or vitrectomy (8). Mean initial BCVA was counting finger (CF) 1 m and at last follow-up (mean 77 months) CF4m with mean improvement of 4.5 lines (early treatment diabetic retinopathy study) (P=0.05). Intraoperative choroidal hemorrhage occurred in three eyes. The retina was finally attached in 14 eyes, with residual inferior detachment in three eyes with silicone oil in situ. Silicone oil was kept in six of seven eyes because of residual inferior detachment (3) and removal of silicone oil, which led to redetachment (1) or fear of redetachment (2). CONCLUSION: Repair of ARD may require several interventions, with the need to keep silicone oil in several cases due to nystagmus and reduced melanin pigment.

Vascularization is more delayed in amniotic membrane graft than conjunctival autograft after pterygium excision.

PURPOSE: To monitor the development of graft vascularization by indocyanine green angiography (ICGA) after pterygium excision with limbal-conjunctival autograft transplantation (LCAT) and amniotic membrane transplantation (AMT). DESIGN: Randomized prospective interventional case series. METHODS: Anterior segment ICGA findings at one, seven, and 30 days after surgery were evaluated in eyes with primary pterygium treated by excision and LCAT (14 eyes of 14 patients) or AMT (13 eyes of 13 patients), and the results for graft vascularization were compared. RESULTS: All conjunctival autografts showed early vascularization from underlying episcleral vascular bed as multiple hyperfluorescent foci at the graft margin on postoperative day 7; graft vascularization was complete on postoperative day 30. In contrast, all grafts in AMT group showed no graft vascularization at any stage after pterygium surgery. This delay of vascularization with AMT persisted until one month after surgery. CONCLUSIONS: Anterior segment ICGA is useful to monitor graft vascularization after pterygium surgery. Graft health after LCAT may be demonstrated by early graft vascularization and perfusion; however, there is a delay in graft vascularization after AMT that may be related to the antiangiogenic effects of the membrane. Further study is needed to demonstrate the relationship between this delay of graft perfusion and early postoperative pterygium recurrence.

Regression of neovascular posterior capsule vessels by intravitreal bevacizumab.

We present a 76-year-old woman who developed neovascularization of the posterior capsule 1 year after extracapsular cataract extraction. She had type 2 diabetes for 15 years, with proliferative diabetic retinopathy that had been treated with panretinal photocoagulation. The neovascular vessels on the posterior capsule originated from existing rubeosis iridis and regressed after a single injection of intravitreal bevacizumab (Avastin). The patient's visual acuity increased to 20/40 after an uneventful neodymium:YAG capsulotomy.

Comparison of conjunctival autograft with amniotic membrane transplantation for pterygium surgery: surgical and cosmetic outcome.

PURPOSE: To compare the clinical results of conjunctival autograft and amniotic membrane transplantation (AMT) for primary and recurrent pterygium excision. In an effort to determine whether AMT yields acceptable cosmetic results as conjunctival autografting in pterygium surgery, we compared the final cosmetic outcomes of these 2 techniques. METHODS: We performed a prospective, randomized clinical study of 78 eyes (78 patients) divided into 2 groups. Forty eyes (28 with primary and 12 with recurrent pterygia) received conjunctival limbal autograft (group 1), and 38 eyes (27 with primary and 11 with recurrent pterygia) received AMT (group 2) after extensive removal of pterygium. Mean follow-up time was 16.6 +/- 3.52 months in group 1 and 13.4 +/- 2.08 months in group 2. The results were evaluated by clinical examination and photographing and final appearances were graded from 1 to 4. Grade 4 represented true recurrence, whereas grade 3 indicated unacceptable cosmetic appearance. RESULTS: Recurrence rates of primary, recurrent, and all pterygia in group 1 and group 2 were 3.6%, 16.7%, and 7.5% and 3.7%, 18.2%, and 7.9%, respectively. There was no significant difference in recurrence rates between the 2 groups (P = 1.00 for all). The rates of final appearance as grade 3 were 10.0% in group 1 and 21.1% in group 2, and the difference was statistically significant (P = 0.048). No major complications occurred during the follow-up period. CONCLUSIONS: Although better results in the final appearance were achieved using conjunctival autografting than with AMT, AMT can be a useful alternative in pterygium surgery, especially in those patients who may have a limited amount of conjunctiva for future surgeries.

Clinical results of phacoemulsification in patients with uveitis.

BACKGROUND AND OBJECTIVE: To evaluate the results of phacoemulsification and posterior chamber intraocular lens (IOL) implantation in patients with uveitis. PATIENTS AND METHODS: Review of records of 37 eyes of 31 patients with uveitis (14 men and 17 women; mean age, 49.8 years; age range, 26 to 71 years) who underwent phacoemulsification with IOL implantation. The data recorded were age, gender, IOL type, treatment modalities, final visual outcome, and complications. RESULTS: Panuveitis, anterior uveitis, posterior uveitis, and intermediate uveitis were detected in 16 (51.6%), 9 (29.0%), 5 (16.1%), and 1 (3.3%) of the patients, respectively. At 6 months postoperatively, 32 (86.5%) eyes had achieved a best-corrected visual acuity of 20/40 or better, and 22 (59.5%) eyes had a visual acuity of 20/20. Five (13.5%) eyes showed limited improvement in postoperative visual acuity due to posterior segment problems. Postoperative recurrence of inflammation occurred in 12 eyes (32.4%) of 10 patients and was treated and controlled with medical therapy. CONCLUSION: When inflammation in uveitic eyes is under complete control, phacoemulsification and implantation of a foldable acrylic IOL in the posterior chamber is safe, effective, and tolerated well. To minimize vision-limiting complications, these patients must be observed closely after surgery, and must be treated aggressively if the inflammation recurs.

Evaluation of choroidal and retinal thickness measurements in adult hemodialysis patients using spectral-domain optical coherence tomography.

PURPOSE: To assess the effect of hemodialysis on retinal and choroidal thicknesses using spectral-domain optical coherence tomography (SD-OCT). METHODS: In this prospective interventional study, 25 hemodialysis patients (17 male, 8 female) were enrolled. All participants underwent high-speed, high-resolution SD-OCT (λ=840 mm; 26.000 A-scans/s; 5 µm resolution) before and after hemodialysis. Choroidal thickness was measured perpendicularly from the outer edge of the retinal pigment epithelium to the choroid-sclera boundary at the fovea and at five additional points: 500 µm and 1000 µm nasal to the fovea and 500 µm, 1000 µm, and 1500 µm temporal to the fovea. Two masked physicians performed the measurements. Choroidal and retinal thicknesses before and after hemodialysis were compared. RESULTS: The median choroidal thicknesses before and after hemodialysis were 182 µm (range, 103-374 µm) and 161 µm (range, 90-353 µm), respectively (P<0.001). The median retinal thicknesses were 246 µm (range, 179-296 µm) before and 248 µm (range, 141-299 µm) after hemodialysis (P>0.05). Systolic arterial pressure, diastolic arterial pressure, mean arterial pressure, heart rate, and ocular perfusion pressure significantly decreased after hemodialysis (P<0.001). Intraocular pressure did not vary significantly (P=0.540). CONCLUSION: Hemodialysis seems to cause a significant decrease in choroidal thickness, whereas it has no effect on retinal thickness. This significant decrease in choroidal thickness might be due to the extensive fluid absorption in hemodialysis, which could result in decreased ocular blood flow.

Effect of 1- and 6-Hour-Delayed Corneal Collagen Cross-Linking on Corneal Healing in a Rabbit Alkali-Burn Model: Clinical and Histological Observations.

PURPOSE: To study the effect of 1- and 6-hour-delayed corneal collagen cross-linking (CXL) on wound-healing of experimental alkali burns of the cornea. METHODS: Twenty-four albino rabbits were used. Alkali burns were created using 1 M NaOH. The animals were divided randomly into 2 groups: group 1 (control group, n = 6) and group 2 (experimental group, n = 18). The experimental group was further divided into 3 subgroups as follows: group 2A, untreated (non-CXL) subgroup; group 2B, 1-hour-delayed CXL treatment subgroup; and group 2C, 6-hour-delayed CXL treatment subgroup. All rabbits were examined periodically for 21 days after treatment and then killed. The corneas were excised and histologically examined. RESULTS: Corneal ulceration, edema, and opacity scores were 4.0 ± 1.64, 1.6 ± 0.65, and 3.5 ± 1.21 in group 2A, 1.5 ± 1.76, 1.3 ± 0.87, and 3.1 ± 1.12 in group 2B, and 2.0 ± 1.90, 1.5 ± 0.79, and 3.3 ± 1.09 in group 2C, respectively. These scores were significantly less in groups 2B and 2C than in group 2A (P = 0.023, P = 0.043, and P = 0.034, respectively). Corneal epithelialization, evident upon staining, was best in group 2B and worst in group 2A (P = 0.012). Histopathology revealed that destruction of corneal collagen fibers and infiltration of inflammatory cells into corneal tissue were reduced in groups 2B and 2C compared with group 2A. CONCLUSIONS: We found that CXL treatment exerted positive effects on severe alkali-induced corneal burns. However, the effects were more pronounced in the 1-hour treatment group. We believe that CXL treatment may be a possible treatment for corneal alkali burn.

Evaluation of choroidal thickness using spectral-domain optical coherence tomography in patients with migraine: a comparative study.

PURPOSE: To assess choroidal thickness in patients with migraine and compare them with healthy controls, using spectral-domain optical coherence tomography (OCT). METHODS: In this prospective case-control study, choroidal thicknesses of 20 newly diagnosed migraine patients and 20 age- and sex-matched healthy subjects were measured using a high-speed, high-resolution frequency domain (FD) OCT device (λ = 840 nm, 26.000 A-scans/s, 5 µm axial resolution). All patients underwent a complete ophthalmic examination before the measurements. OCT measurements were taken at the same time of day (9:00 AM), in order to minimize the effects of diurnal variation. RESULTS: There was a statistically significant difference in median choroidal thickness between the migraine patients (277.00 [interquartile range (IQR) 85.75] µm) and controls (301.00 [IQR 90.50] µm) (p = 0.012). There were significant differences at all measurement points (p<0.05 for all). CONCLUSIONS: The decreased choroidal thickness of patients with migraine might be related to the vascular pathology of the disease. Further studies are needed to evaluate the etiopathologic relationship between choroidal thickness and migraine.

Choroidal thickness changes in patients with migraine.

This observational study evaluated choroidal thickness using spectral domain optical coherence tomography (SD-OCT) in patients with migraine and compared the results with healthy controls. The study population consisted of 42 migraine patients (36 females and 6 males) who were referred from neurology clinics and 42 controls (36 female and 6 male) with no systemic or ocular disease and no headache of any type. All 84 patients underwent complete ophthalmic examination as well as determination of choroidal thickness using a high-speed, high-resolution SD-OCT device (λ = 840 nm, 27.000 A-scans/s, 5-µm axial resolution). The migraine patients were classified into the migraine with aura group or the migraine without aura group, and a pain score from 1 to 10 was determined for each patient based on the Visual Analogue Scale (VAS). The mean choroidal thicknesses were 276.81 ± 37.76 µm in the migraine group and 300.44 ± 24.93 µm in controls. The difference in choroidal thickness between the migraine patients and the controls was significant (P = 0.001). Choroidal thickness measurements of five patients during an attack showed an acute decrease (mean 45.50 µm) in choroidal thickness from the values in the same patients during the attack-free period. There was no correlation between VAS score and the type of migraine with choroidal thickness (P > 0.05). The decrease in mean choroidal thickness in patients with migraine compared to controls may be related to the vascular pathology of the migraine. The acute decrease in choroidal thickness during an attack also lends support to this hypothesis of reduced ocular blood flow in these patients.