Long-term efficacy and safety of brolucizumab in neovascular age-related macular degeneration: A multicentre retrospective real-world study.

PURPOSE: To investigate the long-term efficacy and safety of intravitreal brolucizumab (BRZ) injections in patients with typical neovascular age-related macular degeneration (typical nAMD) and polypoidal choroidal vasculopathy (PCV). METHODS: This multicentre retrospective study included 401 eyes of 398 patients with nAMD who received BRZ injection(s), with a follow-up duration of ≥12 months. Changes in best-corrected visual acuity (BCVA), retinal fluid evaluation and central subfield thickness (CST) on optical coherence tomography were assessed. The efficacy of BRZ was compared between typical nAMD and PCV groups. RESULTS: Analyses were conducted with 280 eyes of 278 patients with typical nAMD and 121 eyes of 120 patients with PCV (mean age, 71.1 ± 8.6 years). 29 eyes (7.2%) were treatment naïve. The mean follow-up period was 15.3 ± 2.8 months; the mean number of BRZ injections within 1 year was 4.5 ± 1.7. BCVA was maintained during the follow-up period, and CST significantly improved from the first injection month and was maintained for 12 months in both the typical nAMD and PCV groups. The dry macula proportion increased from 2.7% at baseline to 56.1% at 1 month and 42.9% at 12 months. Among the 18 eyes that underwent indocyanine green angiography both before and after treatment, 10 (55.6%) showed polyp regression. Overall, the incidence of intraocular inflammation (IOI), retinal vasculitis and occlusive retinal vasculitis was 9.4% (38 eyes), 1.2% (5 eyes) and 0.5% (2 eyes), respectively. IOI occurred from the first to the sixth injections, with an average IOI onset of 28.5 ± 1.4 days. All eyes achieved IOI resolution, although the two eyes with occlusive retinal vasculitis showed a severe visual decline after IOI resolution. CONCLUSION: Brolucizumab was effective in maintaining BCVA and managing fluid in eyes with nAMD for up to 1 year, exhibiting a high polyp regression rate. However, the not uncommon incidence of IOI and the severe visual decline caused by the rare occlusive retinal vasculitis following BRZ treatment underscore the importance of careful monitoring and timely management.

Changes in intraocular pressure following intravitreal dexamethasone implant in patients with history of glaucoma filtration surgery.

PURPOSE: This study aimed to evaluate changes in intraocular pressure following intravitreal dexamethasone implant injection, specifically in patients undergoing glaucoma filtration surgery. METHODS: The degree of increase in intraocular pressure was compared retrospectively among three groups. Group 1 comprised patients who underwent prior glaucoma filtration surgery (54 eyes). Group 2 included patients with or suspected glaucoma without such surgical history (20 eyes). Group 3 included patients without glaucoma (33 eyes). Pressure measurements were taken before the injection and at 1, 2, 3, and 6 months post-injection. A subgroup analysis was performed for pressure > 35 mmHg, > 30 mmHg, > 25 mmHg, and a difference > 10 mmHg between the peak and baseline pressure. RESULTS: Group 1 consistently displayed lower pressures compared with Group 2, with significant difference at both 1- and 6-month post-injections (15.09 mmHg vs. 18.10 mmHg, P = 0.042 and 13.91 mg vs. 17.25 mmHg, P = 0.040). The proportion of patients in Group 1 and Group 3 with pressures > 25 mmHg, > 30 mmHg, and a difference > 10 mmHg did not significantly differ (15.6% vs. 9.5%, P = 0.231; 3.1% vs. 2.3%, P = 0.867; and 17.1% vs. 7.1%, P = 0.231). Notably, Group 2 exhibited a significantly higher proportion within each category (> 25 mmHg, 24.0%; > 30 mmHg, 20.0%; > 10 mmHg difference, 28.0%). CONCLUSION: Intravitreal dexamethasone implant did not increase the risk of elevated intraocular pressure in patients with a history of glaucoma filtration surgery compared with patients with suspected glaucoma; the risk was similar to those without glaucoma.

Spontaneous resolution of long-standing choroidal effusion after glaucoma drainage implant surgery without significant visual deterioration : a case report.

BACKGROUND: Choroidal effusion is a common complication of glaucoma surgery. Although most cases of choroidal effusions resolve spontaneously with observation or medical management alone as intraocular pressure normalizes, surgical drainage might be needed in severe or persistent cases. Herein, we report a case of spontaneous resolution of long-standing severe choroidal effusion after Ahmed glaucoma valve implantation. CASE PRESENTATION: An 85-year-old man with uncontrolled primary open-angle glaucoma and medical history of chronic kidney disease underwent uneventful Ahmed glaucoma valve implantation. On postoperative day 8, transient hypotony occurred, and large 360° peripheral choroidal detachments developed. Although the intraocular pressure increased to normal levels on postoperative day 15, choroidal effusion did not resolve. Fundus examination over 8 months showed that the large choroidal effusion persisted despite a well-controlled intraocular pressure. Laboratory test performed at preoperatively and follow-up period revealed persistently elevated potassium and creatinine levels. On postoperative 9 months, the lesion resolved spontaneously without any surgical intervention. We found that the patient's creatinine level was normalized, pre-existing hyperkalemia was corrected, and accordingly his general condition was improved. CONCLUSIONS: Considering the underlying medical condition may be helpful in patients with persistent choroidal effusion of an unclear etiology following glaucoma filtering surgery.

Predictors of treatment outcomes following treat-and-extend regimen with aflibercept for branch retinal vein occlusion: post-hoc analysis of the PLATON trial.

We investigated predictors of visual outcomes and injection interval in macular edema (ME) secondary to branch retinal vein occlusion (BRVO) treated with a treat-and-extend (TAE) regimen. All 48 patients in a multicenter study were followed for 52 weeks and received three monthly intravitreal aflibercept injections before the TAE regimen, with treatment intervals adjusted by 4 weeks, up to a maximum of 16 weeks. Various laboratory biomarkers and optical coherence tomography parameters were evaluated. Patients were classified into the extension failure group if they had ≥ 1 treatment interval decreased due to an increase in the central macular thickness compared to the previous visit and 18 patients were assigned to this group. In multivariate logistic analyses, presence of microaneurysms and prominent middle limiting membrane (p-MLM) sign, increased initial external limiting membrane (ELM) disruption, and higher total cholesterol were correlated with inhibiting a sustained extension in the injection interval (P = 0.015, P = 0.032, P = 0.037, P = 0.009, respectively). Therefore, in the patients with ME secondary to BRVO with these risk factors, early consideration of frequent injection may improve treatment outcome.

Case Report: A case of ultra-late recurrence of KIF13A-RET fusion non-small cell lung cancer response to selpercatinib.

Background: Cancer recurrence remains a significant problem, and most postoperative recurrences of non-small cell lung cancer (NSCLC) develop within 5 years after resection. We present a rare case of ultra-late recurrence of NSCLC accompanying choroidal metastasis with KIF13A-RET fusion 14 years after the definitive surgery. Case description: A 48-year-old female patient who had never-smoked presented with decreased visual acuity. She had been treated with right upper lobe lobectomy followed by adjuvant chemotherapy 14 years prior. Fundus photographs revealed bilateral choroidal metastatic lesions. Positron emission tomography-computed tomography (PET-CT) scans showed extensive bone metastases and focal hypermetabolism in the left uterine cervix. An excision biopsy of the uterus showed primary lung adenocarcinoma with immunohistochemistry of TTF-1+. Plasma next-generation sequencing (NGS) identified the presence of KIF13A-RET fusion. After 6 months of selpercatinib therapy, PET-CT revealed a partial response for bone and uterine metastasis and stable disease for choroidal lesions. Conclusion: In this case report, we are reporting a rare case of ultra-late recurrence of NSCLC in a patient with choroidal metastasis. Furthermore, the diagnosis of NSCLC with RET fusion was based on liquid-based NGS rather than tissue-based biopsy. The patient showed a good response to selpercatinib, which supports the efficacy of selpercatinib as a treatment for RET-fusion-positive NSCLC with choroidal metastasis.

Prospective trial of treat-and-extend regimen with aflibercept for branch retinal vein occlusion: 1-year results of the PLATON trial.

PURPOSE: To evaluate the functional and anatomical outcomes of a treat-and-extend (TAE) regimen with aflibercept for treatment-naive macular edema (ME) secondary to branch retinal vein occlusion (BRVO). METHODS: This was a prospective, multicenter, noncomparative, open-label clinical trial. Forty-eight eyes of 48 patients received three monthly intravitreal aflibercept injections prior to the TAE regimen. However, if the best-corrected visual acuity (BCVA) was ≥ 20/20 and the central macular thickness (CMT) was < 250 µm during the loading phase, the patient immediately proceeded to the TAE regimen. The treatment interval was adjusted by 4 weeks based on changes in CMT. The primary outcome was the mean change in BCVA from baseline to 52 weeks. RESULTS: The mean change in BCVA was 23.6 ± 14.2 letters. The proportion of patients with BCVA gain ≥ 15 letters was 77.1% at 24 weeks and 72.9% at 52 weeks. The mean reduction in CMT was 326.2 ± 235.6 µm at 24 weeks and 324.2 ± 238.0 µm at 52 weeks. The mean number of injections was 6.7 ± 1.2 (range: 6-11, all patients received three monthly intravitreal aflibercept injections) over 52 weeks, and 34 patients (70.8%) reached the maximal extension interval of 16 weeks at 52 weeks. CONCLUSIONS: The TAE regimen using aflibercept for ME secondary to BRVO, which has a treatment interval of up to 16 weeks, showed comparable efficacy to the fixed-dosing regimen along with reduced treatment burden.

Long-term outcomes of prediction error after combined phacoemulsification and trabeculectomy in glaucoma patients.

BACKGROUND: To investigate long-term outcomes of prediction error after phacotrabeculectomy and to determine risk factors that may cause unstable prediction error after phacotrabeculectomy in glaucoma patients. METHODS: A total 120 eyes of 120 patients who had underwent uncomplicated phacotrabeculectomy (combined group) or phacoemulsification (phaco-only group) were included. Best-corrected visual acuity (BCVA), intraocular pressure (IOP) were measured before and after surgery, and anterior segment parameters including anterior chamber depth (ACD), lens vault (LV), and anterior vault (AV) measured using anterior-segment optical coherence tomography were compared between the two groups. The mean absolute error (MAE) at 3, 6, 12, and 24 months postoperatively were compared. Risk factors associated with unstable prediction error (MAE ≥ 0.5) were investigated in the combined group. RESULTS: In both groups, BCVA was improved and IOP was decreased significantly. MAE at 3, 6, 12, 24 months postoperatively were not significantly different between two groups. The risk factors for unstable prediction error after 12 months of phacotrabeculectomy were old age and LV. Whereas, the only factor predicting unstable prediction error after 24 months of phacotrabeculectomy was LV. The cut-off value of LV for predicting unstable refractive error analyzed by the ROC curve was 0.855 mm. CONCLUSIONS: Phacotrabeculectomy may be an effective treatment with stable long-term outcomes of prediction error similar to phacoemulsification in patients with glaucoma. However, elderly patients or patients with large LV may be predisposed to unstable prediction error after phacotrabeculectomy.

Effects of Eurya japonica extracts on human corneal epithelial cells and experimental dry eye.

Eurya japonica (EJ) leaves have been indicated to exert anti-oxidative and anti-inflammatory effects. Dry eye disease (DED) is a chronic inflammatory disease and oxidative stress is closely associated with DED. The aim of the present study was to analyze the therapeutic efficacy of EJ in DED using human corneal epithelial (HCE) cells and a mouse model of experimental dry eye (EDE). EJ extracts (0.001, 0.01 and 0.1%) were used to treat HCE cells. Cell viability and mitochondrial function were detected using a EZ-Cytox cell viability assay kit and mitochondrial membrane potential assays. Dichlorofluorescein diacetate (DCF-DA) assay was used to measure cellular reactive oxygen species (ROS) levels. Subsequently, eye drops consisting of BSS or 0.001%, 0.01 and 0.1% EJ extracts were applied for treatment of EDE. At 7 days, conjunctival ROS production was measured using a DCF-DA assay. Tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, 10 kDa interferon gamma-induced protein 10 (IP-10) and monokine induced by interferon-γ (MIG) levels in the conjunctiva were analyzed using a multiplex immunobead assay. Tear film and ocular surface parameters were measured. Treatment with EJ extracts in HCE cells effectively improved cell viability, ROS levels and mitochondrial function. Mice treated with 0.01 and 0.1% EJ extracts indicated a significant decrease in ROS, TNF-α, IL-1ß, IP-10 and MIG levels compared with the EDE or BSS groups. Furthermore, a significant improvement in all clinical parameters was observed in the 0.01 and 0.1% EJ extract groups. EJ extracts could decrease cytotoxicity and ROS production in HCE cells. Additionally, topical EJ extracts reduced oxidative damage and inflammation and improved clinical signs of EDE, suggesting that EJ extracts may be used as an adjunctive therapy for DED.

Simple transscleral fixation of IOL technique without tying up haptics.

AIM: To introduce a novel technique for transscleral fixation of the posterior chamber intraocular lens (PC-IOL) that requires no sutures on the IOL haptics. METHODS: Instead of suturing polypropylene onto the IOL haptics, the method simply winds the thread on the haptics. Fifteen eyes of 15 patients underwent this technique and were followed up for more than 18mo. Surgical outcomes and post-operative complications were evaluated and compared with those of the conventional transscleral fixation method. RESULTS: Postoperative cylinder was significantly lower in the thread winding group than in the conventional transscleral fixation method group (-1.02±0.46 diopters vs -1.57±0.77 diopters; P=0.01). Further, no postoperative complications, such as optic capture, IOL dislocation, and hyphema, were detected in the thread winding group. CONCLUSION: We believe that our thread winding technique is better than previously reported methods because it is simple, mechanically stable, and free from suture-related complications.

Effect of epidermal growth factor ointment on persistent epithelial defects of the cornea.

BACKGROUND: Healthy corneal epithelium acts as a barrier against damage to the deeper structures in the eye. Failure in the mechanisms of corneal epithelization can lead to persistent epithelial defects of the cornea (PEDs) and can compromise its function. Epidermal growth factor (EGF) promotes the proliferation, migration, and differentiation of epithelial cells, endothelial cells, and fibroblasts during wound healing and may be beneficial in treating patients with PEDs. We, therefore, investigated the effect of EGF ointment on patients with PEDs. METHODS: Fifteen patients with PEDs refractory to conventional treatment were treated twice a day with EGF ointment. Patient demographics and comorbidities were noted. The epithelial healing time was determined along with the primary outcome measures in the areas of the epithelial defects, visual acuity, visual analog scale (VAS) scores, and esthesiometer scores 1 month and 2 months after treatment. RESULTS: Five eyes of herpetic keratitis (33.3%), 3 eyes of dry eye disease (20.0%), 3 eyes of bacterial keratitis (20.0%), 2 eyes of limbal stem cell deficiency (13.3%), 1 eye of diabetic neurotrophic keratitis (6.7%), and 1 eye of filamentary keratitis (6.7%) were associated with PEDs, respectively. Two months following treatment with EGF ointment, there was a reduction in the area of the epithelial defects (5.7 ± 3.9 to 0.1 ± 0.3 mm2) as well as a significant improvement in best-corrected visual acuity (0.9 ± 0.8 to 0.6 ± 0.5 LogMAR) and VAS scores (4.5 ± 1.2 to 2.5 ± 0.7) in 12 eyes (80%). Among these cases, the mean epithelial healing time was 5.5 ± 1.8 weeks. Amniotic membrane transplantation was performed on the remaining 3 (20.0%) patients that did not respond to EGF treatment. CONCLUSIONS: EGF ointment could reduce symptoms and promotes corneal epithelialization of refractory PEDs. It may, therefore, be well-tolerated and a potentially beneficial addition in the management of refractory PEDs.

Dll4 Suppresses Transcytosis for Arterial Blood-Retinal Barrier Homeostasis.

RATIONALE: Central nervous system has low vascular permeability by organizing tight junction (TJ) and limiting endothelial transcytosis. While TJ has long been considered to be responsible for vascular barrier in central nervous system, suppressed transcytosis in endothelial cells is now emerging as a complementary mechanism. Whether transcytosis regulation is independent of TJ and its dysregulation dominantly causes diseases associated with edema remain elusive. Dll4 signaling is important for various vascular contexts, but its role in the maintenance of vascular barrier in central nervous system remains unknown. OBJECTIVE: To find a TJ-independent regulatory mechanism selective for transcytosis and identify its dysregulation as a cause of pathological leakage. METHODS AND RESULTS: We studied transcytosis in the adult mouse retina with low vascular permeability and employed a hypertension-induced retinal edema model for its pathological implication. Both antibody-based and genetic inactivation of Dll4 or Notch1 induce hyperpermeability by increasing transcytosis without junctional destabilization in arterial endothelial cells, leading to nonhemorrhagic leakage predominantly in the superficial retinal layer. Endothelial Sox17 deletion represses Dll4 in retinal arteries, phenocopying Dll4 blocking-driven vascular leakage. Ang II (angiotensin II)-induced hypertension represses arterial Sox17 and Dll4, followed by transcytosis-driven retinal edema, which is rescued by a gain of Notch activity. Transcriptomic profiling of retinal endothelial cells suggests that Dll4 blocking activates SREBP1 (sterol regulatory element-binding protein 1)-mediated lipogenic transcription and enriches gene sets favorable for caveolae formation. Profiling also predicts the activation of VEGF (vascular endothelial growth factor) signaling by Dll4 blockade. Inhibition of SREBP1 or VEGF-VEGFR2 (VEGF receptor 2) signaling attenuates both Dll4 blockade-driven and hypertension-induced retinal leakage. CONCLUSIONS: In the retina, Sox17-Dll4-SREBP1 signaling axis controls transcytosis independently of TJ in superficial arteries among heterogeneous regulations for the whole vessels. Uncontrolled transcytosis via dysregulated Dll4 underlies pathological leakage in hypertensive retina and could be a therapeutic target for treating hypertension-associated retinal edema.

Intermittent exotropia with a positive Bielschowsky head-tilt test.

AIMS: To investigate the clinical features of patients with intermittent exotropia (IXT) with and without positive Bielschowsky head-tilt test (BHTT), but without superior oblique palsy. METHODS: We retrospectively reviewed the charts of 118 patients with IXT. Patients were divided into two groups according to positive or negative BHTT. Associated risk factors for positive BHTT in patients with IXT were analysed. The changes in the BHTT result after surgery were also analysed. RESULTS: Fifty patients showed a positive BHTT, and 68 patients showed a negative BHTT. There were significant differences between the groups with regard to the elapsed time from the onset of IXT, the angle of distance exodeviation, inferior oblique muscle overaction, vertical deviation at the primary position, suppression and stereoacuity (all for p<0.05). Risk factors for a positive BHTT among patients with IXT were the elapsed period since the onset of IXT (OR, 1.034; 95% CI 1.008 to 1.061, p=0.011), angle of distance exodeviation (OR, 1.087; 95% CI 1.015 to 1.165, p=0.017) and near stereoacuity (OR, 1.006; 95% CI 1.001 to 1.011, p=0.029). Horizontal muscle surgery alone, without cyclovertical muscle surgery, resulted in a significant decrease in the number of patients with positive BHTT (p<0.01). CONCLUSIONS: A positive BHTT was seen in patients with IXT with larger angle exodeviations, longer elapsed time periods since the onset of IXT and worse stereoacuity. The positive BHTT could be eliminated using horizontal muscle surgery only, without complementary inferior oblique muscle weakening surgery.

Comparison of ketorolac 0.45% versus diclofenac 0.1% for macular thickness and volume after uncomplicated cataract surgery.

PURPOSE: To compare the effects of ketorolac 0.45% and diclofenac 0.1% on macular thickness and volume after uncomplicated cataract surgery. METHODS: A total of 76 eyes of 76 patients who underwent uncomplicated cataract surgery were included. Patients were treated with either diclofenac 0.1% (38 eyes) or ketorolac 0.45% (38 eyes) after surgery. The macular thickness and volume were obtained with optical coherence tomography (OCT). Central subfield thickness (CST, OCT 1 mm zone), total foveal thickness (TFT, OCT 3 mm zone), total macular thickness (TMT, OCT 6 mm zone), average macular thickness (AMT) and total macular volume (TMV) were compared between the two study groups. RESULTS: No significant differences between groups were found in macular thickness or volume 1 month after cataract surgery. Two months after surgery, the ketorolac group had significantly lower CST, TFT, TMT and AMT than the diclofenac group (p < 0.05 for all). Additionally, 1 and 2 months after surgery, changes from preoperative values in CST (both p = 0.04), AMT (p = 0.02 and p < 0.01, respectively) and TMV (both p = 0.04) were significantly less in the ketorolac group than in the diclofenac group. CONCLUSIONS: Following uncomplicated cataract surgery, topical ketorolac 0.45% was more effective than diclofenac 0.1% in preventing increases in macular thickness and volume.

ELISA-Confirmed Bilateral Ocular Toxocariasis with Different Features.

PURPOSE: To report a rare case of bilateral ocular toxocariasis with a different clinical presentation in each eye. CASE REPORT: A 56-year-old man presented with severe ocular pain and acute visual loss in the right eye (RE). His best-corrected visual acuity was hand motion in the RE and 20/30 in the left eye (LE). Slit-lamp examination showed a severe anterior chamber reaction in the RE and a moderate anterior chamber reaction in the LE. The fundus of the LE showed a posterior hemorrhagic granuloma with vascular sheathing whereas the fundus of the RE was not visible because of severe vitreous opacification. Blood laboratory testing disclosed hyperproduction of IgE but no eosinophilia. Serum enzyme-linked immunosorbent assay testing was positive for Toxocara canis IgG (1:38). Toxocara antibody was also detected in the aqueous humor from both eyes (RE, 1:321; LE, 1:254). The patient was treated with topical and oral steroids along with oral albendazole. Additionally, phacoemulsification, a therapeutic vitrectomy, and vitreous cultures were performed in the RE. During the vitrectomy, the fundus of the RE showed diffuse retinal vascular obstruction with sheathing. Toxocara antibodies were detected in the vitreous fluid from the RE (1:679). A laser barrier was placed around the granuloma in the LE. After 1 month of steroid therapy, a tapering schedule was started. At 6 months postoperatively, the fundi of both eyes were stable. The final best-corrected visual acuity was 8/20 in the RE and 20/20 in the LE. CONCLUSIONS: A rare case of bilateral ocular toxocariasis is reported with a different clinical presentation in each eye that was diagnosed using enzyme-linked immunosorbent assay analysis of intraocular fluids. Both eyes were successfully treated medically with a vitrectomy eventually being required in the RE.

Higher order aberrations of the corneal surface after laser subepithelial keratomileusis.

PURPOSE: To evaluate the changes of higher order aberrations (HOAs) before and after laser subepithelial keratomileusis (LASEK) and to analyze the influence of tear film instability on HOAs of the corneal surface after LASEK. METHODS: In this cross-sectional study, 31 patients who underwent LASEK were divided into dry eye (16 patients, 32 eyes) and non-dry eye groups (15 patients, 30 eyes). Uncorrected distance visual acuity, spherical equivalent refraction, ablation depth, tear film parameters and Ocular Surface Disease Index (OSDI) questionnaire scores were evaluated in both groups. Total HOA root mean square (RMS), third-order coma, third-order trefoil and fourth-order spherical aberration (SA) of the corneal surface immediately and at 10 seconds after blinking were measured before and after surgery. RESULTS: The total HOA RMS, coma, trefoil and SA significantly increased after LASEK compared with preoperative values in both groups. In the dry eye group, total HOA RMS, coma and trefoil significantly increased except for SA at 10 seconds after blinking compared with those measured immediately after blinking. In addition, the changes of total HOA RMS, coma and trefoil were negatively correlated with tear film break-up time (R = -0.420, -0.473 and -0.439, respectively), but positively correlated with OSDI score (R = 0.433, 0.499 and 0.532, respectively). In the non-dry eye group, there were no significant differences between HOAs measured at 10 seconds after blinking and those measured immediately after blinking. CONCLUSIONS: The HOAs including coma, trefoil and SA significantly increased after LASEK. The tear film instability in the dry eye can be associated with more deterioration of the optical quality after LASEK, due to more significant increase of total HOA RMS, coma and trefoil.

The neuroprotective effect of carnosine (ß-alanyl-L-histidine) on retinal ganglion cell following ischemia-reperfusion injury.

PURPOSE: To investigate whether carnosine can increase retinal ganglion cell (RGC) survival in ischemic mouse retina. METHODS: Retinal ischemia was induced by constant elevation of intraocular pressure (100-110 mmHg) for 60 min in C57BL/6 J mice pretreated with carnosine (1000 mg/kg) or saline. Hypoxia inducing factor-1 alpha (HIF-1α), glial fibrillary acidic protein (GFAP), and dynamin-related protein-1 (Drp-1) expressions were assessed at 6, 12, and 24 h after retinal ischemia. Bax and Bcl-2 expressions were also analyzed at 12 h after retinal ischemia. RGC survival was assessed by retrograde FluoroGold labeling at 2 weeks after retinal ischemia. RESULTS: The expression of HIF-1α, GFAP, and Drp-1 was increased within 24 h after ischemic injury. Carnosine treatment effectively decreased the elevated expression of HIF-1α, GFAP, and Drp-1 in ischemic mouse retina. In ischemic retina treated with carnosine, Bax expression was decreased, whereas Bcl-2 expression was increased compared with ischemic retina treated with saline. Carnosine treatment also protected against RGC loss in ischemia mouse retina. CONCLUSIONS: Our findings showed that carnosine treatment significantly decreased RGC loss through decreased expression of HIF-1α, GFAP, Drp-1, and Bax, and increased expression of Bcl-2 in ischemic mouse retina. We suggest that carnosine can be an effective endogenous neuroprotective molecule in the prevention of RGC loss in ischemic retina.