Change in the Foveal Avascular Zone and Macular Capillary Network Density after Hyperbaric Oxygen Therapy in Healthy Retina.

PURPOSE: This study aimed to evaluate responses in retinal tissue by swept source OCT angiography (OCT-A) to hyperoxia after hyperbaric oxygen (HBO2) therapy. METHODS: The study was conducted in volunteers who received HBO2 treatment but did not have any eye disease. Patients underwent detailed eye examinations including dilated fundus examination, visual acuity, and refraction before being admitted for HBO2 therapy. Measurements were made before and immediately after HBO2 therapy. Enface images of the retinal vasculature were obtained from the superficial and deep retinal plexus (SP/DP). Quantitative analysis of the vessel density (VD) and foveal avascular zone (FAZ) area was performed. RESULTS: In total, 31 patients (15 female) with healthy retina were included in the study. The mean age was 42.8 years. The mean SP vascular density measurements before HBO2 therapy for the right and left eyes were 15.18 ± 1.2 mm - 1 and 15.01 ± 1.3 mm - 1 , respectively; the measurements after HBO2 therapy for the right and left eyes were 14.34 ± 1.4 mm - 1 and 14.48 ± 1.19 mm - 1 . The mean DP vascular density measurements before HBO2 therapy for the right and left eyes were 16.03 ± 1.69 mm - 1 and 16.1 ± 1.45 mm - 1 , respectively; the measurements after HBO2 therapy for the right and left eyes were 15.02 ± 1.65 mm - 1 and 15.12 ± 2.16 mm - 1 , respectively. Reduction of mean VD in superficial and deep plexus after HBO2 was statistically significant (P = 0.001 and P = 0.000, respectively). Changes in mean FAZ area before and after HBO2 therapy were not statistically significant (P = 0.719). CONCLUSION: The healthy retina responds to oxygen supersaturation with HBO2 therapy by eventually decreasing vascular density in all layers. These findings may be important for further studies especially related to retina and choroidal oxygenation.

Hyperbaric oxygen treatment results in a group of Turkish central retinal artery occlusion patients with a combined presence of thrombophilic mutations.

Background: Central retinal artery occlusion (CRAO) is a rare ocular-ischemic syndrome causing irreversible blindness. Its pathophysiology has not been clarified, and no targeted therapies are available yet. Hyperbaric oxygen (HBO2) therapy is already an approved therapy for CRAO and has been shown to improve the visual acuity of CRAO patients safely. However, further clinical data are required to classify HBO2 therapy as a type-I general agreement for CRAO. Materials and Methods: Eleven patients with non-arteritic CRAO were enrolled. Patient demographics, medical history, detailed eye examinations, HBO2 therapy results, pre-/post HBO2 therapy visual acuity measurements and genotypes for common thrombophilic mutations (Factor V G1691A Leiden, Factor II G20210A, MTHFR A1298C, MTHFR C677T, and PAI-1-675 4G/5G) were obtained. Result: Six patients (54%) responded to HBO2 therapy compared to five non-responders (46%). Patients admitted before 12 hours responded well to HBO2 therapy. No systemic diseases nor advanced age were statistically correlated to CRAO. A combination of mutations rather than single mutations for each patient could be seen as responsible for CRAO. No Factor V G1691A Leiden mutations and only one FII G20210A mutation were observed. Eight patients (72%) had MTHFR 677T allele, five patients (45%) had MTHFR 1298C allele, and 10 patients (91%) had the PAI-1-675 4G allele. Conclusion: Not a single mutation but a combination of mutations and other unknown factors probably lead to CRAO, and if intervention is timely, HBO2 therapy offers improvement in visual acuity safely.

Ocular and Systemic Results of Intravitreal Bevacizumab Injection in Retinopathy of Prematurity Treatment.

OBJECTIVES: The aim of this study was to evaluate the effectiveness and safety of an intravitreal bevacizumab injection (IVB) in the treatment of retinopathy of prematurity (ROP). METHODS: The medical records of patients who had received IVB treatment for ROP between January 2014 and October 2018. Anatomical and functional outcomes were evaluated. The Denver II Developmental Screening Test was administered and fluorescein angiography (FA) was performed in some cases. RESULTS: Thirty-eight eyes of 19 infants were included in the study. An IVB injection was administered to 9 infants with aggressive posterior ROP (APROP) disease (Group 1), 6 infants with any stage ROP with plus disease in zone I (Group 2), and 4 infants with stage 2-3 ROP with plus disease in zone II (Group 3). Complete retinal vascularization was observed in 24 eyes of 12 infants who received a single dose of bevacizumab without any additional treatment. Recurrence of the disease was observed in 12 eyes of 6 infants diagnosed with APROP and laser photocoagulation was performed. FA was performed to 5 IVB patients whose parents approved the procedure. The Denver II Developmental Screening Test was administered to all of the participants, and the test outcomes were consistent with the corrected age of the children, though 2 infants demonstrated a developmental delay in gross motor development tasks. Overall, good anatomical and functional results were obtained. CONCLUSION: IVB is an effective and relatively safe treatment modality for infants with ROP; however, prospective studies are required to provide more detailed information about systemic side effects.

The safety and effectiveness of 0.16 mg bevacizumab plus or minus additional laser photocoagulation in the treatment of retinopathy of prematurity.

Purpose: Retinopathy of prematurity (ROP) is the leading cause of preventable blindness in premature infants. Antivascular endothelial growth factor (anti-VEGF) therapy has been used increasingly in treatment as a pharmacological alternative to laser therapy. In this study, we evaluate the results of low-dose anti-VEGF treatments. Methods: Design: Retrospective--observational study. Infants who had been evaluated for ROP disease between February 2016 and February 2017 were assessed. We retrospectively reviewed the ROP stages, treatment results, and complications. Laser photocoagulation (LPC) and intravitreal bevacizumab (0.16 mg IVB) were used for treatment and fundus fluorescein angiography (FFA) was also performed in some of the cases. Results: IVB was applied to 43 infants. A macular hole was seen in one infant's eye after IVB. LPC was applied to avascular areas in 21 infants. In three patients, persistence of the disease was observed after administration of a low dose of IVB. Additional LFK was performed in these patients. None of the infants who received LPC had any complications. Conclusion: IVB is increasingly becoming the first-line treatment for ROP. For severe ROP, 0.16 mg IVB is effective. Using LPC to treat avascular areas after 70 weeks' gestational age (GA) may decrease the risk of late recurrence and appears to be a safe treatment to use.

Effects of Common Thrombophilia Factor Mutations in Central Retinal Vein Occlusion.

OBJECTIVES: Central retinal vein occlusion (CRVO) is a severe eye disease that impairs vision. Although numerous systemic conditions have been reported to be a contributor, its exact pathophysiology has not yet been resolved. The purpose of this study was to study the role of some common thrombophilic polymorphisms in CRVO patients. METHODS: A total of 33 CRVO patients (25 non-ischemic CRVO and 8 ischemic CRVO) and 30 controls were recruited. Factor V Leiden (G1691A), prothrombin (Factor II G20210A), MTHFR (C677T), MTHFR (A1298C), and PAI-1 5G/4G polymorphisms in venous blood DNA samples were examined, as well as the presence of hypertension, diabetes mellitus, glaucoma, smoking, and history of thrombosis. RESULTS: It was determined that MTHFR C677T polymorphisms, either in heterozygous or homozygous form, might be a risk factor for CRVO and systemic thrombosis. No differences were detected between the CRVO and control groups in terms of diabetes mellitus (p=0.058>0.05), hypertension (p=0.3>0.05), smoking (p=0.923>0.05), glaucoma (p=0.06>0.05) or use of anticoagulant drugs (p=0.4>0.05). Analysis of patient history revealed a statistically significant difference regarding a thrombotic event in the medical history of the CRVO group (p=0.001<0.05; n=4) versus the control group. The ischemic CRVO group had a significantly higher incidence of diabetes mellitus (p=0.002<0.05) and hypertension (p=0.031<0.05) than the non-ischemic CRVO group. CONCLUSION: The MTHFR C677T mutation appears to be a risk factor for CRVO but factor V Leiden (G1691A), prothrombin (Factor II G20210A), MTHFR (A1298C), and PAI-1 5G/4G mutations were not determined to be specifically related to CRVO in this study. The presence of diabetes mellitus and hypertension was significant in the ischemic CRVO group. Further studies with larger sample sizes should be conducted.

Effect of hyperbaric oxygen treatment in central retinal artery occlusion.

BACKGROUND: Central retinal artery occlusion (CRAO) is a rare and serious ophthalmologic emergency with a bad prognosis. Hyperbaric oxygen (HBO2) treatment has been reported to improve visual acuity of CRAO patients. However, there are unknown variables for HBO2 treatment such as initiation period, number of sessions and efficacy. In this study, we aimed to investigate efficacy of HBO2 treatment in CRAO patients. METHODS: Patients who had been diagnosed with CRAO and referred to our Hyperbaric Oxygen Treatment Unit with the indication of HBO2 treatment were included in the study. Patient demographics, their systemic diseases, best-corrected visual acuity (BCVA) and the time of visual loss were recorded. Oral acetazolamide and topical beta blocker treatments as well as HBO2 treatments were administered to patients as soon as possible. Patients received 20 treatments as standard. Visual acuity was examined and recorded following each HBO2 treatment administration. RESULTS: 10 eyes (five right, five left) of 10 patients) were included in the study. While average visual acuity was LogMAR 3 before the treatment, it was measured as LogMAR 1.8 on average after treatment (P ⟨ 0.05). None of the patients were observed to have neovascular glaucoma. CONCLUSIONS: HBO2 treatment is an efficacious method with few side effects and can be used in the treatment of CRAO patients. During acute and subacute periods a certain number of HBO2 treatment sessions may be beneficial. Stopping treatments before eight completed HBO2 sessions for a patient who did not show improvement until that time may miss a patient who would have benefited from HBO2 treatment.

Comparison of the Effect of Intravitreal Dexamethasone Implant in Vitrectomized and Nonvitrectomized Eyes for the Treatment of Diabetic Macular Edema.

PURPOSE: To compare the effectiveness of sustained-release dexamethasone (DEX) intravitreal implant in nonvitrectomized eyes and vitrectomized eyes with diabetic macular edema (DME). METHODS: A retrospective review of the medical records of 40 eyes of 30 consecutive patients with diabetic macular edema who underwent intravitreal DEX implant injection. Patients were divided into 2 subgroups: 31 eyes that were nonvitrectomized (group 1) and 9 eyes that had previously undergone standard pars plana vitrectomy (group 2). The main outcome measures were BCVA and foveal thickness (FT). RESULTS: A significant improvement was seen in BCVA in both group 1 and group 2 at the 1st, 2nd, and 6th months after treatment with DEX implant (p < 0.05). In group 1, a significant reduction in FT was observed at the 1st, 2nd, and 6th months (p < 0.05). In group 2, a significant reduction in FT was seen at the 1st and 2nd months (p < 0.05), but the reduction rate at the 6th month after the injection was not statistically significant (p = 0.06). CONCLUSION: DEX implant is effective for the treatment of diabetic macular edema, and the effectiveness of the drug is similar in vitrectomized and nonvitrectomized eyes.

Iris-claw intraocular lens implantation in children with ectopia lentis.

PURPOSE:: Artisan iris-claw lens implantation (AICLI) is a surgical technique for treating ectopia lentis. We aimed to compare visual outcomes and possible long-term complications of AICLI surgery in pediatric patients with ectopia lentis with or without a diagnosable hereditary disease. METHODS:: Seventeen children with non-traumatic ectopia lentis were retros pectively classified into two groups: group 1 included children with a diagnosable hereditary disease (11 patients, 65%), and group 2 included children without any definable hereditary disease (six patients, 35%). Patients were evaluated for post-surgical refraction, best-corrected visual acuity, and clinical follow-up complications. RESULTS:: The average follow-up time was 38 months, and the average age of the patients was 103 ± 53 months (30-196 months). Best-corrected visual acuity values were significantly increased in both groups after surgery (p<0.05). Target refraction values were achieved at a rate of 47% in group 1 and 22% in group 2. Post-surgery complications, such as lens dislocation (36%, 11 eyes of 10 patients) and hypotonia (10%, three eyes of three patients) were observed in both groups, and retinal detachments (10%, three eyes of three patients) were observed in three patients from group 1. CONCLUSIONS:: Compared with previous similar studies, this study utilized the largest pediatric patient group and had the longest post-surgery follow-up time. Moreover, it is advisable that pediatric patients with non-traumatic ectopia lentis be carefully screened for any underlying hereditary disease, especially diseases related to connective tissue metabolism.

VITREORETINAL SURGERY FOR PATIENTS WITH SEVERE EXUDATIVE AND PROLIFERATIVE MANIFESTATIONS OF RETINAL CAPILLARY HEMANGIOBLASTOMA BECAUSE OF VON HIPPEL-LINDAU DISEASE.

PURPOSE: The evaluation of long-term results of vitreoretinal surgery and retinal capillary hemangioblastoma (RCH) resection in patients with complicated retinal detachment (RD) secondary to RCHs. METHODS: Twelve eyes of 12 patients were operated on with vitreoretinal surgery, including occlusion of afferent and efferent feeder vessels with endodiathermy and endolaser photocoagulation, and subsequent resection of RCHs. The long-term anatomical and visual outcomes were retrospectively evaluated. RESULTS: Total exudative RD was detected in six eyes and subtotal exudative RD was found in the remaining six eyes. A tractional component was present in eight eyes, and four eyes had pure exudative RD. Laser treatment had been previously applied to four eyes but vitreoretinal surgery was the primary treatment in eight eyes. A total of 19 RCHs were resected. The quadrant location of RCHs was superior temporal in six, superior nasal in five, inferior nasal in five, and inferior temporal in three. The dimensions of the RCHs ranged between 1 and 4 disk diameters (DD) (1-DD in 1 eye, 1.5-DD in 3, 2-DD in 10, 2.5-DD in 3, 3-DD in 1, and 4-DD in 1). Preoperative mean logarithm of the minimum angle of resolution visual acuity was 1.9 ± 1.0 (3.0-0.7) (20/1,588 ± 20/200 [20/20,000-20/100]). Silicone oil and C3F8 was applied to four and eight eyes, respectively. The median postoperative follow-up was 30.5 (18-48) months. Single operation and final anatomical success was obtained in 9 and 11 eyes, respectively. Mean logarithm of the minimum angle of resolution visual acuity in the postoperative 18th month and at the final visit were 1.05 ± 0.8 (3.0-0.2) (20/224 ± 20/125 [20/20,000-20/32]) and 0.96 ± 0.8 (3.0-0.2) (20/182 ± 20/125 [20/20,000-20/32]), respectively. New RCHs occurred in eight eyes. Rubeosis iridis was not present in any of the eyes. CONCLUSION: Promising anatomical and visual outcomes were obtained after vitreoretinal surgery and resection of RCHs in eyes with complicated RD secondary to RCH. However, life-long follow-up is needed to recognize recurrent RD seen even in the early period or recurrences of RCHs seen in the long-term period.

Comparison of central corneal thickness estimated by an ultrasonic pachymeter and non-contact specular microscopy.

PURPOSE:: To compare central corneal thickness (CCT) measurements of healthy individuals obtained with ultrasonic pachymetry (UP) and non-contact specular microscopy (NCSM). METHOD:: In total, 148 eyes of 74 subjects with no ocular or systemic diseases were included in the study. Central corneal thickness measurements of all patients performed with UP and NCCM were compared. RESULTS:: A total of 74 subjects (38 females) were included in this study. The mean age was 45.2 ± 18.4 (range 12-85) years. The mean central corneal thickness of all 148 eyes was 546.9 ± 40 µm with UP and 510.8 ± 42 µm with NCSM. The mean central corneal thickness measured with NCSM was 35 µm thinner than that measured with UP (p<0.001). A high degree of agreement was found between the two methods (r=0.942, p<0.001). CONCLUSIONS:: Our results suggest that NCSM measures thinner corneas than UP and that the correction formula we identified should be applied when comparing between these two devices.

Relationship among Corneal Biomechanics, Anterior Segment Parameters, and Geometric Corneal Parameters.

Purpose. To investigate the relationship between corneal biomechanical parameters, anterior segment parameters, and geometric corneal parameters in a healthy Caucasian group. Methods. This retrospective study included the healthy eyes with best corrected visual acuity of at least 20/40 of 122 Caucasian subjects. The anterior segment parameters and geometric corneal parameters such as corneal volume, central corneal thickness, horizontal and vertical corneal radii, anterior and posterior steep, and flat keratometric values were measured with a Scheimpflug camera. The biomechanical properties were measured with Ocular Response Analyzer. Results. One hundred and twenty-two healthy Caucasian subjects (67 males, 55 females) with a mean age of 45.32 ± 20.23 were enrolled. Both corneal hysteresis and corneal resistance factor were positively correlated with CCT (r = 0.529, p < 0.001; r = 0.638, p < 0.001) and CV (r = 0.635, p < 0.001; r = 0.579, p < 0.001) and negatively correlated with age (r = -0.373, p < 0.001; r = -0.249, p < 0.001). Both in age-gender and multivariate models, CH and CRF had statistically significant negative association with the posterior steep K value. Conclusions. CH and CRF are negatively correlated with posterior steep and average posterior K values.

An Important Cause of Blindness in Children: Open Globe Injuries.

Objective. Our aim was to present and evaluate the predictive factors of visual impairment and blindness according to WHO criteria in pediatric open globe injuries. Methods. The medical records of 94 patients younger than 18 years who underwent primary repair surgery were reviewed retrospectively. The initial and final visual acuity, anterior and posterior segment findings, and zone of injury were noted. The patients were classified as blindness in one eye or visual impairment in one eye. Results. Of 412 patients who presented with open globe injury, 94 (23%) were under 18 years old. Fifty-four (16 females, 38 males) children were included. The mean age of the children was 7.1 ± 4.1 years. According to WHO criteria, 19 of 54 patients (35%) had unilateral blindness and 8 had unilateral visual impairment (15%). There was no significant relationship between final visual acuity and gender and injured eye. In visually impaired and blind patients, presence of preoperative hyphema, retinal detachment, and zone 2 and zone 3 injuries was significantly higher. Conclusion. Presence of hyphema and zone 2 and zone 3 injuries and retinal detachment may end up with visual impairment and/or blindness in children.

Sociodemographic status of severely disabled and visually impaired elderly people in Turkey.

PURPOSE: To identify the prevalence of ophthalmologic diseases in elderly patients who had been classified as severely disabled and to identify the ophthalmologic conditions leading to visual impairment and blindness. METHODS: The medical records of 2806 patients who had applied to the Health Board of the Erzurum Region Training and Research Hospital between January 2011 and December 2012 were reviewed. One hundred ninety-nine patients aged >64 years who were classified as severely disabled with disability rates of over 50%, and who were unable to care for themselves or to move and/or communicate without help were included in the study. RESULTS: The most frequently seen disabilities were neurological (47.2%) and those resulting from eye diseases (17.1%). The most common ophthalmologic diseases were cataract, glaucoma, and age-related macular degeneration. The mean right and left eye visual acuities were 1.17 ± 1.10 logMAR and 1.13 ± 1.0 logMAR, respectively. Of the 60 patients with ophthalmologic diseases or conditions, 33 were blind (visual acuity worse than 20/400) and 10 were visually impaired (visual acuity worse than 20/70 but better than 20/400). Cataracts were the main cause of blindness. The mean age of the patients who were still being followed up at the time of application to the disability board was significantly lower than that of the others (p =0.015). Seventy-nine percent of the blind patients were from rural areas, and 88% of these had no regular follow-up. Among the blind and visually impaired, significantly more patients from urban areas had social security insurance (SSI) than those from rural areas (p =0.043). Nearly 64% of the blind patients were women. The follow-up rate was significantly lower in women (p =0.025). According to multinomial logistic regression analysis, the visually impaired and blind patients were more likely to have lower follow-up rates than the other types of severely disabled patients (OR: 0.231, 95% Cl: 0.077-0.688, p=0.009). CONCLUSIONS: Blindness gives rise to severe disability, and the most common ophthalmologic diseases that cause severe disabilities in elderly patients are cataract, glaucoma, and age-related macular degeneration. Sociodemographic factors that may affect the accessibility of visually impaired and blind people to health services include their place of residence and gender.

Unilateral uveitis, cataract and retinal detachment following low-voltage electrical injury.

A 39-year-old woman presented with a gradual worsening of vision in the right eye 1 month after a low-voltage household electrical injury. A slit-lamp examination showed non-granulomatous anterior uveitis with nuclear cataract and an ultrasound examination also showed total retinal detachment. In this letter, we present a rare complication of electrical injury demonstrated as unilateral uveitis, cataract and retinal detachment in a 39-year-old woman.