Comparison of Ranibizumab and Bevacizumab for Macular Edema Associated with Branch Retinal Vein Occlusion

PURPOSE: To assess the effectiveness and safety of intravitreal ranibizumab compared with bevacizumab for the treatment of macular edema associated with branch retinal vein occlusion (BRVO). METHODS: This was a retrospective study of 80 eyes with macular edema associated with BRVO. Patients received either 0.5 mg of ranibizumab (n = 24) or 1.25 mg of bevacizumab (n = 56) intravitreally. Both groups received three initial monthly injections followed by as-needed injections. The best-corrected visual acuity, central subfield thickness, mean number of injections, and retreatment rate were evaluated monthly for 6 months after the initial injection. RESULTS: The best-corrected visual acuity significantly improved from logarithm of the minimal angle of resolution (logMAR) 0.55 ± 0.26 at baseline to 0.24 ± 0.26 at 6 months in the ranibizumab group (p < 0.001) and from logMAR 0.58 ± 0.21 at baseline to 0.29 ± 0.25 at 6 months in the bevacizumab group (p < 0.001), which is not a statistically significant difference (p = 0.770). The mean reduction in central subfield thickness at 6 months was 236 ± 164 µm in the ranibizumab group (p < 0.001) and 219 ± 161 µm in the bevacizumab group (p < 0.001), which is not also a statistically significant difference (p = 0.698). The mean numbers of ranibizumab and bevacizumab injections were 3.25 ± 0.53 and 3.30 ± 0.53, respectively (p = 0.602). In addition, after the three initial monthly injections, the retreatment rates for ranibizumab and bevacizumab injections were 20.8% and 26.7%, respectively (p = 0.573). CONCLUSIONS: Both ranibizumab and bevacizumab were effective for the treatment of BRVO and produced similar visual and anatomic outcomes. In addition, the mean number of injections and the retreatment rates were not significantly different between the groups.

A Case of Repeated Dexamethasone Implantation in a Suspected Patient with IRVAN Syndrome

PURPOSE: In the present study, a case of repeated intravitreal dexamethasone implantation for a suspected idiopathic retinal vasculitis, aneurysms and neuroretinitis (IRVAN) syndrome associated with recurrent exudative retinal detachment and macular edema is reported. CASE SUMMARY: A 39-year-old female who underwent steroid pulse therapy due to Vogt-Koyanagi-Harada disease in the left eye was referred for exudative retinal detachment and macular edema. Best corrected visual acuity (BCVA) was 1.0 in the right eye and 0.5 in the left eye. Cystoid macular edema combined with serous retinal detachment was observed on spectral-domain optical coherence tomography. Fluorescein angiography revealed neovascularization and multiple macroaneurysms with fluorescein leakage in the left peripapillary area. Severe peripheral capillary non-perfusion and fluorescein leakage were also observed in both eyes. Intravitreal dexamethasone implantation was performed in the left eye and macular edema showed wax-and-wane pattern. No edema was observed after 4 additional dexamethasone implantations, however, preretinal hemorrhage occurred in the peripapillary area during treatment. Seventeen months after initiation of treatment, BCVA was 0.6 in the left eye and dry macula was maintained. CONCLUSIONS: Repeated intravitreal dexamethasone implantation was effective for recurrent macular edema in a patient suspected with IRVAN syndrome.

The Repeatability of Retinal Layer Thickness Measurements with Spectral-Domain Optical Coherence Tomography in Normal Eyes

PURPOSE: To evaluate the repeatability of retinal layer thickness measurements in normal eyes imaged using spectral domain optical coherence tomography (SD-OCT). METHODS: Sixty-eight eyes of 34 healthy subjects were enrolled in this study. Imaging was performed 4 times using 9 × 9 mm macular scans with SD-OCT (RS 3000 Advance HD OCT, NIDEK, Gamagori, Japan) at the same visit by an experienced examiner. After automatic retinal segmentation (layering) in 5 layers, the thickness of each layer was calculated. Macular thickness of 9 Early Treatment of Diabetic Retinopathy Study (ETDRS)-like regions was obtained. Repeatability for each of the 9 subfield areas was calculated by their repeatability coefficients and intraclass correlation coefficients (ICCs). RESULTS: There was no significant difference in average retinal thickness and each retinal layer thickness between all measurements acquired by the experienced examiner. The ICCs of retinal layer thickness ranged from 0.826 to 0.847 for the ganglion cell layer + inner plexiform layer, inner nuclear layer + outer plexiform layer and outer nuclear layer + external limiting membrane in the fovea. The ICCs were greater than 0.909 for the other intra-retinal layers in all 9 ETDRS subfield thickness between all measurement pairs. CONCLUSIONS: Excellent repeatability was observed for SD-OCT retinal segmented layer thickness measurements in healthy subjects.

Long-term Outcomes of Diabetic Macular Edema Following Initial Intravitreal Ranibizumab Injection Based on Morphologic Pattern

PURPOSE: To evaluate the 3-year visual and morphological outcomes of diabetic macular edema (DME) based on the morphological pattern observed on optical coherence tomography (OCT) after intravitreal ranibizumab injections. METHODS: Thirty-two eyes of 32 patients with DME were classified according to the following OCT features: diffuse retinal thickening (DRT), cystoid macular edema (CME), and serous retinal detachment (SRD). All patients received 3 consecutive monthly intravitreal injections of 0.5 mg ranibizumab. After 3 injections, patients received ranibizumab or dexamethasone implantation as needed. The primary outcome was the number of treatments received based on the DME type over 36 months. Best-corrected visual acuity (BCVA), central subfoveal thickness, and macular volume changes were also evaluated. RESULTS: The eyes were classified as DRT (n = 16), CME (6), or SRD (10). The mean number of injections over 3 years was significantly different among the groups: DRT (4.25), CME (7.5), SRD (7.6; p = 0.048). The number of patients who did not need additional treatment after the initial 3 injections was 13 with DRT (81.3%), 2 with CME (33.3%), and 5 with SRD (50%; p = 0.045). BCVA at 36 months significantly improved from baseline in the DRT group (p = 0.003). The CME group showed the worst BCVA among the groups (p = 0.023). Six patients who received intravitreal dexamethasone implantation showed no significant improvement of BCVA but significant decrease in macular volume from 12 to 36 months. CONCLUSIONS: Clinical courses varied according to the morphological pattern of DME after intravitreal ranibizumab injection, and patients with DRT maintained visual and anatomical improvement with fewer injections over 36 months. Additional dexamethasone implantation showed limited effect in reducing macular edema with persistent macular cystic change, but no significant improvement in visual acuity.

Cytoprotective Effect of Polyphenolic Compounds against Oxidative Stress in Cultured Retinal Pigment Epithelial Cells

PURPOSE: Grape seed-derived polyphenols (GSPs) provide a concentrated source of polyphenols having antioxidant capacity. In this study we investigated the cytoprotective effect of GSP against oxidative stress-induced cell damage in cultured human retinal pigment epithelial (RPE) cells. METHODS: Cultured adult retinal pigment epithelium (ARPE)-19 cells were incubated with GSP from Vitis vinifera (0.1, 0.5, 1, 5 or 10 microg/mL) for 24 hours and treated with hydrogen peroxide (H2O2, 0.4 mM) for 24 hours to induce oxidative stress. Cell viability was measured using 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. Intracellular reactive oxygen species (ROS) was quantified using 2',7'-dichlorofluorescein diacetate (DCF-DA) fluorescence. RESULTS: The percentage of viable RPE cells was significantly lower in cultures treated with H2O2 0.4 mM than in control cultures. GSP significantly reduced H2O2-induced cell death in a dose dependent manner. GSP at 0.1, 0.5, 1, 5 and 10 microg/mL significantly reduced cell mortality due to the treatment with H2O2. Intracellular ROS production increased significantly in cultures treated with H2O2 0.4 mM compared with control. There was a significant dose-dependent decrease in intracellular ROS levels after treatment of RPE with GSP. CONCLUSIONS: GSP, a natural polyphenolic compound, can protect RPE cells from H2O2-induced oxidative stress and reduce intracellular ROS production by scavenging free radicals. This suggests potential effects of polyphenolic compounds against retinal diseases associated with oxidative stress.

A Case of Aspergillus Endophthalmitis as a Preceding Symptom of Central Nervous System Lymphoma

PURPOSE: To report a rare case of Aspergillus endophthalmitis as a preceding symptom of central nervous system (CNS) lymphoma. CASE SUMMARY: A 66-year-old female was admitted to our clinic with mental change for 3 days. Seven months earlier, she had been diagnosed with retinal vasculitis in an ophthalmology clinic because of blurred vision in both eyes and was administered steroid therapy. Three months earlier, because of progressive symptoms, vitreous fluid culture had been performed and showed Aspergillus endophthalmitis. She was treated with intravitreous voriconazole injection and oral voriconazole. Initial brain magnetic resonance imaging (MRI) and cerebrospinal fluid study was normal. Two months later, a second MRI showed multiple enhancing lesions, which were aggravated on the third MRI at admission to our clinic. Although brain biopsy was not performed due to the poor condition of the patient, CNS lymphoma was suspected based on the neuroimaging. After steroid pulse therapy and whole brain radiation, follow-up neurologic examination showed improved mental state, and follow-up MRI showed remarkable shrinkage of multiple lesions. CONCLUSIONS: As Aspergillus endophthalmitis is an opportunistic infection in those with an immune-compromised state and the orbit is near the central nervous system, the clinician should be alert to concomitant disorders in CNS. For a prompt and accurate diagnosis of CNS disorder, early evaluation of neurologic symptoms beyond symptoms of endophthalmitis and neuroimaging is essential.

Non-human Immunodeficiency Virus-related Ocular Syphilis in a Korean Population: Clinical Manifestations and Treatment Outcomes

PURPOSE: To describe the clinical manifestations and treatment outcomes of ocular syphilis in patients without human immunodeficiency virus (HIV) infection. METHODS: A total of 45 eyes from 39 patients with ocular syphilis confirmed by serologic tests were reviewed retrospectively. The included cases were all non-HIV-infected patients presenting with intraocular inflammation from 2002 to 2014 at Kyung Hee University Hospital. Medical records of 45 eyes were analyzed and included best-corrected visual acuity and ophthalmologic examination findings of the anterior and posterior segments to determine the focus of inflammation. Optical coherence tomography and fluorescein angiography findings as well as both medical and surgical management were also analyzed. RESULTS: The mean patient age was 61.0 years (range, 37 to 89 years). Bilateral ocular involvement occurred in 6 patients (15.4%), and diagnoses at presentation were most frequently related to posterior uveitis (38%), followed by panuveitis (29%) and optic neuritis (11%). Isolated interstitial keratitis and intermediate uveitis were uncommon (4%, both). Twenty-eight eyes (62.2%) were treated with penicillin, and 11 eyes (24.4%) underwent surgical treatment. The mean baseline best corrected visual acuity was 0.79 ± 0.59 (mean ± standard deviation, logarithm of the minimum angle of resolution) and significantly improved to 0.60 ± 0.63 at the final follow-up after treatment (p = 0.019). Mean visual improvement was significantly greater in the penicillin-treated group (p = 0.001). Visual impairment at the final visit occurred in 11 eyes (24.4%). Among the visual impairment group, 10 eyes (90.1%) had posterior segment-involving uveitis. CONCLUSIONS: Visual outcomes of treated, non-HIV-related ocular syphilis were favorable regardless of time to presentation. Posterior segment-involving uveitis at presentation was associated with poor visual outcome.

Macular Hole Formation after Pars Plana Vitrectomy for the Treatment of Valsalva Retinopathy: A Case Report

We report a case of complete surgical resolution of Valsalva retinopathy that manifested as a premacular hemorrhage involving a membrane followed by a macular hole (MH) resulting from the first vitrectomy. A 20-year-old female patient was referred to our hospital due to sudden vision loss in the left eye. Her best-corrected visual acuity (BCVA) in the left eye was hand motion. Fundus photographs and optical coherence tomography (OCT) revealed a premacular hemorrhage. Nine weeks later, the BCVA in the left eye had returned to 20 / 100 and the premacular hemorrhage had completely resolved, but residual sub-internal limiting membrane deposits and a preretinal membrane were present. The preretinal membrane was removed by core vitrectomy and preretinal membrane peeling, but the foveal deposits could not be excised. Two weeks after the first vitrectomy, the deposits resolved spontaneously, but a full-thickness MH was present. Six months after a second vitrectomy with fluid-gas exchange, the BCVA in the left eye had improved to 20 / 25 and OCT showed that the MH had closed. This case illustrates the possibility of MH formation following vitrectomy for Valsalva retinopathy.

Macular Hole Formation after Pars Plana Vitrectomy for the Treatment of Valsalva Retinopathy: A Case Report

We report a case of complete surgical resolution of Valsalva retinopathy that manifested as a premacular hemorrhage involving a membrane followed by a macular hole (MH) resulting from the first vitrectomy. A 20-year-old female patient was referred to our hospital due to sudden vision loss in the left eye. Her best-corrected visual acuity (BCVA) in the left eye was hand motion. Fundus photographs and optical coherence tomography (OCT) revealed a premacular hemorrhage. Nine weeks later, the BCVA in the left eye had returned to 20 / 100 and the premacular hemorrhage had completely resolved, but residual sub-internal limiting membrane deposits and a preretinal membrane were present. The preretinal membrane was removed by core vitrectomy and preretinal membrane peeling, but the foveal deposits could not be excised. Two weeks after the first vitrectomy, the deposits resolved spontaneously, but a full-thickness MH was present. Six months after a second vitrectomy with fluid-gas exchange, the BCVA in the left eye had improved to 20 / 25 and OCT showed that the MH had closed. This case illustrates the possibility of MH formation following vitrectomy for Valsalva retinopathy.

Effects of Macular Ischemia and Early Treatment on Visual Outcome in Branch Retinal Vein Occlusion

PURPOSE: To evaluate the effects of macular ischemia and early treatment on the visual outcomes of patients with branch retinal vein occlusion (BRVO). METHODS: This study retrospectively reviewed the records of 42 patients who were treated with an intravitreal bevacizumab injection for BRVO, repeated 3 times at 6-week intervals and were whose data available for a follow-up period of at least 4 years. Best-corrected visual acuity (BCVA) and optical coherence tomography (OCT) results before treatment and at 6, 12, 24, 36 and 48 months after the 3 serial injections, were measured. We assessed macular ischemia, time to the first treatment, and the relationship of these with BCVA. RESULTS: Mean BCVA (log MAR) was significantly improved from 0.67 +/- 0.43 at baseline to 0.30 +/- 0.30 at 48 months (p 6 weeks) treatment groups in BCVA and mean change in BCVA after 48 months. There was statistically significant (p 6 weeks) treatment groups with macular ischemia in BCVA after 48 months. CONCLUSIONS: In patients with BRVO, a significant visual improvement was maintained after intravitreal bevacizumab injections, despite the presence of macular ischemia. Early treatment (within 6 weeks) is more effective for maintaining and improving visual acuity. Similar results in the macular ischemia group confirmed the importance of early treatment.

Two Cases of Intravitreal Ganciclovir Injection for Cytomegalovirus Retinitis

PURPOSE: To report 2 cases of cytomegalovirus retinitis treated with intravitreal ganciclovir. CASE SUMMARY: A 29-year-old female (Case 1) who received immunosuppressive therapy with tacrolimus and mycophenolate mofetil for 3 months after pancreatic transplantation, was given an intravitreal Bevacizumab injection 4 times in each eye under the suspicion of bilateral central retinal vein occlusion. During follow-up, a new lesion with white opacification and multiple snowballs appeared in the left eye. Suspecting cytomegalovirus retinitis, we administered an intravitreal ganciclovir injection resulting in a decrease of white opacification and improvement of visual acuity. A 66-year-old male (Case 2) who was receiving treatment for general weakness and heart failure, presented with visual disturbance in both eyes. Fundoscopic examination revealed white opacification, multiple snowballs and retinal hemorrhage in the left eye; diagnostic vitrectomy was performed. Macular edema and subretinal fluid continued after the vitrectomy and the serologic testing revealed an IgG titer positive for cytomegalovirus, therefore, an intravitreal injection of ganciclovir was given. Macular edema and subretinal fluid decreased and visual acuity improved. CONCLUSIONS: Intravitreal ganciclovir can be an effective treatment option for the management of CMV retinitis.

Imported Intraocular Gnathostomiasis with Subretinal Tracks Confirmed by Western Blot Assay

We report a case of intraocular gnathostomiasis diagnosed by western blot assay in a patient with subretinal tracks. A 15-year-old male patient complained of blurred vision in the right eye, lasting for 2 weeks. Eight months earlier, he had traveled to Vietnam for 1 week and ate raw wild boar meat and lobster. His best-corrected visual acuity was 20/20 in both eyes and anterior chamber examination revealed no abnormalities. Fundus examination showed subretinal tracks in the right eye. Fluorescein angiography and indocyanine green angiography showed linear hyperfluorescence of the subretinal lesion observed on fundus in the right eye. Ultrasound examination revealed no abnormalities. Blood tests indicated mild eosinophilia (7.5%), and there was no abnormality found by systemic examinations. Two years later, the patient visited our department again for ophthalmologic evaluation. Visual acuity remained 20/20 in both eyes and the subretinal tracks in the right eye had not changed since the previous examination. Serologic examination was performed to provide a more accurate diagnosis, and the patient's serum reacted strongly to the Gnathostoma nipponicum antigen by western blot assay, which led to a diagnosis of intraocular gnathostomiasis. This is the first reported case of intraocular gnathostomiasis with subretinal tracks confirmed serologically using western blot in Korea.

Prognostic Factors in Vitrectomy for Macular Epiretinal Membrane

PURPOSE: To identify prognostic factors associated with a favorable outcome after vitrectomy for patients with macular epiretinal membrane (ERM). METHODS: The authors retrospectively reviewed the records of 63 patients (64 eyes) with macular ERM, who were treated by vitrectomy between 2003 and 2008, and followed for more than 6 months. RESULTS: The mean follow-up period was 13.21 +/- 9.11 months and the mean best corrected visual acuity after vitrectomy was log MAR 0.32 +/- 0.34. Univariate analysis revealed the patients in the group with a postoperative log MAR of 0.3 or better had better preoperative visual acuity and shorter symptom duration; multivariate analysis revealed the same results. In 24 eyes, intraretinal structures which contained pseudoholes, intraretinal cysts, retinal folds and vitreoretinal traction were analyzed with Cirrus HD-OCT, however, there was no correlation with visual acuity after vitrectomy. CONCLUSIONS: The present study demonstrated vitrectomy for macular ERM resulted in favorable visual improvement. The preoperative visual acuity and symptom duration were a significant prognostic factor.

Two-Year Results of Intravitreal Bevacizumab Injection in Retinal Vein Occlusion

PURPOSE: The authors evaluated the 2-year clinical results of intravitreal bevacizumab injection in retinal vein occlusion (RVO). METHODS: Thirty-two eyes of 32 patients treated with an intravitreal bevacizumab injection of 1.25 mg (0.05 ml) for RVO (branch RVO: 22 eyes, central RVO: 10 eyes), repeated 3 times at a 6-week interval and were available for a follow-up period of at least 2 years were retrospectively reviewed. Best-corrected visual acuity (BCVA) before treatment and 6, 12, and 24 months after 3 serial injections, was recorded. The optical coherence tomography (OCT) results were analyzed to identify prognostic factors for recurrent macular edema that needed reinjection. RESULTS: Two years after the treatment, mean BCVA was significantly improved (p = 0.000). Out of 32 eyes, 16 (branch RVO: 8 eyes; central RVO: 8 eyes) needed reinjection because of recurrent macular edema. In central RVO, a significantly high reinjection rate was shown in serous retinal detachment (SRD) compared with cystoid macular edema (CME) as identified in OCT findings (p = 0.049). Additionally, in branch RVO, a high reinjection rate was shown in SRD, although statistically not significant (p = 0.375). CONCLUSIONS: In patients with RVO, a significant visual improvement was maintained for at least 2 years after intravitreal bevacizumab injection. Based on OCT results, SRD showed a high reinjection rate compared with CME in CRVO.

A Case of Ciliochoroidal Detachment After Patterned Scanning Laser Photocoagulation With Short Exposure Time

PURPOSE: To report the case of a patient with ciliochoroidal detachment after brief exposure to patterned scanning laser photocoagulation. CASE SUMMARY: We examined a 62-year-old woman with early proliferative diabetic retinopathy and observed neovascularization and macular edema upon fundus examination. The patient underwent patterned scanning laser photocoagulation with an exposure time of 0.03 sec over the entire retina in a single pass. In vivo, the ciliary body and choroid were examined using ultrasound biomicroscopy (UBM), before, immediately after, 3 and 7 days after panretinal photocoagulation. Ciliochoroidal detachment was observed 3 days after panretinal photocoagulation and spontaneously disappeared by 7 days after photocoagulation. The change in IOP coincident with ciliochoroidal detachment were not significant. CONCLUSIONS: Ciliochoroidal detachment after panretinal photocoagulation may lead to complications such as angle-closure glaucoma. Patterned scanning laser photocoagulation with short exposure time should be practiced only with careful attention to the possible development of cilochoroidal detachment.

A Validation and Reliability Study of the Korean Version of National Eye Institute Visual Function Questionnaire 25

PURPOSE: To translate and evaluate the reliability and validity of the Korean version of the National Eye Institute Visual Functioning Questionnaire-25 (NEI-VFQ-25). METHODS: Two bilingual ophthalmologists independently translated the original English version of the NEI-VFQ-25 into written Korean. A panel of the Korean Retina Society reviewed the translations to form a single reconciled forward translation of the Korean version of the NEI-VFQ-25. Another ophthalmologist back-translated this first draft into English. Both the first draft and back-translated draft were edited by a professional translator. To evaluate the correlation and validity, results between the original NEI-VFQ-25 and the Korean version, completed by the bilingual participants, were compared. RESULTS: The Korean version of the National Eye Institute Visual Functioning Questionnaire-25 was developed by translation, back-translation, and expert supervision. Results from 23 bilingual participants between the original NEI-VFQ-25 and the Korean version were compared and showed statistically significant correlation, with a Spearman's correlation coefficient of 0.4 or greater. The Kolmogorov-Smirnov test results showed no statistically significant differences between the two questionnaires. CONCLUSIONS: Translation and validation of the Korean version of the NEI-VFQ-25 was achieved.

Early and Late Intravitreal Bevacizumab Injection in Macular Edema Due to Branch Retinal Vein Occlusion

PURPOSE: To compare the effects of early and late intravitreal injection of bevacizumab in patients with macular edema (ME) due to branch retinal vein occlusion (BRVO). METHODS: The study sample included 56 eyes of 56 patients who received intravitreal bevacizumab injection for ME due to BRVO and were followed up with at least six months of observation. We retrospectively divided eyes into two classes that included 36 eyes with a disease duration of 3 months (late treatment group). We assessed the effects of injection on the best corrected visual acuity (BCVA), central retinal thickness and IOP at one, three, and six months after treatment. RESULTS: There was no statistically significant differences in terms of sex, age, number of injections, ischemia, pre-injection visual acuity and central retinal thickness between the two treatment groups. Improvements in central retinal thickness were observed in both groups but were not significantly different between the groups. Visual acuity improved in both groups after treatment; the improvement was significantly better in the early treatment group observed three and six months after treatment. IOP did not change after treatment in either group. CONCLUSIONS: In cases of ME due to BRVO, early intravitreal bevacizumab injection is more effective than late injection for maintaining and improving visual acuity.

Long-Term Results of Intravitreal Bevacizumab Injection for Macular Edema: Retinal Vein Obstruction and Diabetic Retinopathy

PURPOSE: To evaluate the long-term results of intravitreal bevacizumab injection for macular edema (ME) due to retinal vein obstruction (RVO) and diabetic retinopathy (DR). METHODS: The objects of study were patients with decreased visual acuity due to ME with RVO and DR for whom intravitreal injections of 1.25 mg (0.05 ml) bevacizumab were repeated three times with an interval of six weeks and who were available for a follow-up period of more than 12 months. The patients underwent additional bevacizumab injections if ME increased as assessed by optical coherence tomography (OCT). Best-corrected visual acuity (BCVA) and central macular thickness (CMT) were measured at baseline and follow-up visits. RESULTS: There were 16 patients with RVO and 18 patients with DR. In the RVO group, the mean length of follow-up was 12.4+/-1.1 months, the mean baseline BCVA was 0.75+/-0.32 and the final BCVA was 0.42+/-0.25, a difference that was statistically significant (p0.05). The mean CMT at baseline was 462.0+/-195.0 microm and decreased to a mean of 282.2+/-177.3 microm at the end of the follow-up period (p<0.05). CONCLUSIONS: In RVO and DR, three injections of intravitreal bevacizumab with an interval of six weeks and additional injections as indicated were effective in reducing ME and showed especially good results in improvement of visual acuity for ME due to RVO.

The Comparison of Macular Thickness Measurements and Repeatabilities Between Time Domain and Spectral Domain OCT

PURPOSE: To compare macular thickness measurements obtained from time domain optical coherence tomography (TD-OCT) and 2 spectral domain (SD) OCTs and to evaluate their repeatability and agreement in normal subjects and diabetic macular edema patients. METHODS: Fifty-four healthy, normal subjects and 26 diabetic macular edema patients were participated in this study. In a randomly selected eye from each subject, two serial macular measurements were obtained from TD-OCT (Stratus OCT) and SD-OCTs (Cirrus HD-OCT, Spectralis HRA+OCT) by an experienced technician in random order. Nine areas of macular thickness map and repeatabilities obtained by the 3 OCTs were compared. RESULTS: In relative repeatability, SD-OCT showed better results overall compared to TD-OCT. Macular thickness was greatest in the Spectralis HRA+OCT in both normal subjects and diabetic macular edema patients, followed by Cirrus HD-OCT and Stratus OCT. In normal subjects, regardless of the type of comparison between the machines there was a statistically significant difference in all 9 areas. CONCLUSIONS: While the TD-OCT and the 2 SD-OCTs are reliable for macular thickness measurement, SD-OCT has better measurement repeatability compared with TD-OCT. Because macular measurements obtained from the 3 OCT systems cannot be interchanged, an effort should be made to standardize the measurement of each system.

Comparison of Vitreolytic Effect in Rabbit Eyes: Plasmin, Hyaluronidase, and Their Mixtures

PURPOSE: The aim of the present study was to quantify and compare the vitreolytic effect of plasmin, hyaluronidase, and a combination of the two. METHODS: Thirty-six rabbits were randomized into 3 groups: (A) twelve rabbits had an intravitreal injection of plasmin 1 U with hyaluronidase 10 U/0.1 mL into the right eye, (B) twelve rabbits had an injection of plasmin alone (1 U/0.1 mL), and (C) twelve rabbits had an injection of hyaluronidase alone (10 U/0.1 mL). The left eye of each rabbit was used as control, which was injected with 0.1 mL phosphate buffered saline (PBS). The eyes were enucleated 1 hour and 24 hours after injection. The volume of fluid-type vitreous and gel-type vitreous was measured with a micropipette using the melting point as the difference. Statistical analysis was performed and light microscopy was used to assess potential damage to the retinal tissue. RESULTS: The volume of remaining gel-type vitreous was measured as 52.5%, 60.3%, 59.2%, and 76.5% after 1 hour enucleation and as 44.6%, 56.7%, 56.1%, and 74.7%, after 24 hours enucleation in group A, B, C, and control group, respectively. Group A, B, and C showed statistically significant differences against the control group. Group A (plasmin with hyaluronidase) showed less remaining gel-type vitreous volume than a single injection of plasmin or hyaluronidase alone. CONCLUSIONS: Intravitreal injection of plasmin with hyaluronidase showed more vitreolytic effect than a single injection of plasmin or hyaluronidase alone. The enzyme may be useful in liquefying the vitreous, and may be a useful biochemical adjunct to vitrectomy.