No Abstract Available.
Retinal Detachment* ; Retinaldehyde*

PURPOSE: We compared the clinicopathologic effects of TTT between pigmented and albino rabbits. METHODS: TTT was delivered using infrared diode laser at 810 nm(Iris Medical Instrument, Mountain Veiw, CA, USA) and applied with spot size of 3 mm, duration of 60 seconds. At 1 week and 4 weeks after TTT, fundus photographs and simultaneous FAG/ICG angiogram were taken with SLO(Scanning Laser Ophthalmolscopy, Rodenstock, Munish, Germany). Light and electron microscopic examination were performed. RESULTS: In pigmented rabbits, visible funduscopic change was visible even with minimal power setting(100 mW). Obliteration of choroidal vessels was observed on ICG angiogram. In microscopic examination, entire layers of neural retina, retinal pigment epithelial cells, and deep choroid were severely damaged at the center of treated fields. Whereas, in albino rabbits fundus changes were not observed at any power setting. However, focal thrombosis at margin of lesion was identified on ICG angiogram after power of 300 mW. In microscopic examination, tissue damage was developed up to 600 mW and the lesion extended into the superficial choroid posteriorly and outer neural retina anterioly. CONCLUSIONS: The effect of TTT was increased with fundus pigmentation. Clinically we should adjust TTT power setting according to the amount of melanin pigmentation in the fundus.
Choroid ; Epithelial Cells ; Lasers, Semiconductor ; Melanins ; Pigmentation ; Rabbits ; Retina* ; Retinaldehyde ; Thrombosis

PURPOSE: There were many studies on the distributions of the retinal ganglion cells(RGC) in the experimental model of the retinal ischemia. RGC was known to be more sensitive to the ischemic injury than the other types of the retinal cells. So, we would identify the changes of the retinal ganglion cell morphologies and distribution after the iatrogenic retinal ischemia induced by intraocular pressure(IOP) elevation. METHODS: Eight pigmented and six white rabbits were used and retinal ischemia was induced by increasing IOP higher than 120 mmHg for 60 minutes. Electroretinogram were recorded at 6 days or 13 days, and histologic findings were observed at 7 or 14 days. RESULTS: After 7 days, RGC densities decreased, cytoplasmic staining disappeared, and the intranuclear hyperpigmentation was noted. RGC densities decreased significantly at 14 days. In the vertical retinal section, some flattening of retinal ganglion cell layer and inner plexiform layer was observed. Changes in the cellular morphologies were prominent. CONCLUSIONS: It may be more appropriate to examine both the retinal whole-mount and the vertical tissue section for the estimatation of the changes of retinal ganglion cell layer in the pressure-induced retinal ischemia.
Cytoplasm ; Ganglion Cysts* ; Hyperpigmentation ; Ischemia ; Models, Theoretical ; Rabbits ; Retina* ; Retinal Ganglion Cells ; Retinaldehyde*

PURPOSE: To present a case of leukemic infiltration of the optic nerve head as the initial manifestation of leukemic relapse. CASE SUMMARY: A 65-year-old woman was diagnosed with acute myeloid leukemia. Complete remission was achieved after 4 complete courses of chemotherapy. She complained of a sudden decrease in visual acuity in her left eye. Fundus examination showed severe optic disc edema with peripapillary hemorrhage and serous retinal detachment. Visual acuity and fundus continued to aggravate and high-dose intravenous steroid therapy was instituted. Visual acuity and fundus deteriorated more after treatment. Brain magnetic resonance imaging and CSF study were normal but intrathecal chemotherapy and focal irradiation were performed on account of the suspected CNS involvement of leukemia. Morphologic improvement in the retinal structure was achieved, however, optic atrophy remained and her vision did not recover. CONCLUSIONS: The present case shows the involvement of the optic nerve head as the initial isolated manifestation for the relapse in a patient with complete remission. CNS involvement is rare in acute myeloid leukemia and in particular, the optic nerve is rarely reported as the initial isolated presentation for the relapse. Moreover, the disease progression relatively aggravated after treatment. In the atypical aspects of leukemic relapse, the present case was noticeable.
Aged ; Brain ; Disease Progression ; Edema ; Eye ; Female ; Hemorrhage ; Humans ; Leukemia ; Leukemia, Myeloid, Acute ; Leukemic Infiltration ; Magnetic Resonance Imaging ; Optic Atrophy ; Optic Disk ; Optic Nerve ; Recurrence ; Retinal Detachment ; Retinaldehyde ; Vision, Ocular ; Visual Acuity

PURPOSE: To describe the results and complications of combined pars plana vitrectomy and phacoemulsification with intraocular lens implantation in patients with proliferative diabetic retinopathy, and to analysis the factors to be associated with visual outcome. METHODS: Retrospective study was performed on 70 eyes of 58 patients who had undergone combined pars plana vitrecotmy and phacoemulsification with intraocular lens implantation because of proliferative diabetic retinopathy. Preoperative, intraoperative, and postoperative complicated factors to be associated with visual outcome were analyzed. RESULTS: The changes of visual acuity were classified into "improved" 57eyes (81%), "stationary" 7eyes (10%), and "decreased" 6eyes (9%). Posterior capsule rupture during operation was occurred in 2 eyes (2.9%). After cataract, macular edema and neovascular glaucoma were developed in order of incidence of postoperative complications. The factors to be associated with visual outcome were diabetic nephropathy, posterior capsule rupture, macular edema, neovascular glaucoma, and retinal detachment. (P<0.05) CONCLUSIONS: Combined pars plana vitrectomy and phacoemulsification with intraocular lens implantation may be relatively safe for the patients with proliferative diabetic retinopathy.
Cataract ; Diabetic Nephropathies ; Diabetic Retinopathy* ; Glaucoma, Neovascular ; Humans ; Incidence ; Lens Implantation, Intraocular* ; Lenses, Intraocular* ; Macular Edema ; Phacoemulsification* ; Postoperative Complications ; Retinal Detachment ; Retrospective Studies ; Rupture ; Visual Acuity ; Vitrectomy*

PURPOSE: To report on the classification of congenital stationary night blindness (CSNB) and multifocal ERG findings. METHODS: We studied three patients (case 1-3) with night blindness but normal fundus and one patient (case 4) with decreased vision after trauma with respect to the patients' medical history, familial history, refraction, slit lamp examination, fundus examination, FAG, ERG, and multifocal ERG. RESULTS: The ERG in case 1 showed a decreased rod response, and this patient was diagnosed with Riggs-type CSNB. The typical "negative ERG" was found in all three cases of ERG (except case 1), and these cases were diagnosed with Schubert-Bornschein-type CSNB. Based on Miyake's classification, case 2 was incomplete, and cases 3 and 4 were complete. The mfERG of the cases with complete Schubert-Bornschein type had delayed implicit times of the first-order kernel and decreased amplitudes of the second-order kernel. The delayed implicit times and the decreased amplitudes of the first- and second-order kernels were found in the cases of Riggs- type and incomplete Schubert-Bornschein-type.
Classification* ; Humans ; Night Blindness*

PURPOSE: To evaluate the early ERG (electroretinogram) changes in N-methyl-N-nitrosourea (MNU)-induced retinal degeneration in rats. METHODS: Thirty-six 6-week-old male rats were injected intraperitoneally with 60mg/kg MNU and divided into 6 groups. Histology and ERG were recorded for the rats of each group before treatment and at 3, 6, 12, 18, and 24 hours after MNU injection. Promptly after the ERG recording, rats were sacrificed and the eyeballs prepared for histologic sectioning. The Tdt-mediated dUTP-digoxigenin nick end labeling (TUNEL) method was used to detect photoreceptor cell death. RESULTS: The first decreases of ERG responses were noticed maximally at 3 hours after the treatment. Thereafter, the amplitude of the responses was partially recovered at 12 hours post-treatment. The second decrease of ERG amplitudes was observed in the 18-hour recordings, and those changes progressed to 24 hours after the treatment. In the histologic findings, TUNEL (+) cells in the Outer Nuclear Layer (ONL) were not detected at 3 hours after MNU injection, but were initially noticed at 6 hours post-injection. CONCLUSIONS: The first decreases of ERG amplitudes proceeded the appearance of TUNEL (+) cells in ONL, and these electrophysiological changes seemed to not be related to photoreceptor cell death. We propose that electrophysiological changes observed might be related to the MNU-induced activity enhancement of guanylate cyclase in the phototransduction pathway. We also show that photoreceptor cell death in the MNU-induced retinal degeneration model occurs at 6 hours after the treatment, which is earlier than the results of previous reports.
Animals ; Guanylate Cyclase ; Humans ; In Situ Nick-End Labeling ; Light Signal Transduction ; Male ; Methylnitrosourea ; Photoreceptor Cells ; Rats* ; Retinal Degeneration* ; Retinaldehyde*

PURPOSE: To evaluate macular function before and after surgical closure of idiopathic macular hole using multifocal electroretinogram (mfERG). METHODS: The mfERGs were performed on nine patients, who had been diagnosed with idiopathic macular hole, before and after vitrectomy (average 2.9+/-0.6 mo) and gas (C3F8) injection. VERISTMsystem (EDI: San Mateo, CA, USA) was used to record the mfERGs. The central 30 degrees of the ocular fundus were stimulated by an array of 103 hexagonal elements for 4 minutes. The responses of six concentric rings (rings 1 to 6) radiating from the foveal center were averaged. Preoperative and postoperative responses of mfERG were compared. Statistical differences were analyzed with the paired two sample t-test. RESULTS: N1, P1 and N2 amplitudes of rings 1 and 2 increased after surgery significantly (p<0.05). N1, P1 and N2 latencies mostly decreased after surgery, but these results were not significant (p>0.05). The changes of mfERG responses were not correlated with the changes of visual acuities after surgery. Visual acuity was improved in seven patients but deteriorated in the other two, one of whom developed RPE degeneration and another cataract. CONCLUSIONS: The mfERG responses improved after macular hole surgery. These results suggest that mfERG may be a useful method to assess macular function changes after macular hole surgery, although the responses were not correlated with visual acuity.
Cataract ; Humans ; Retinal Perforations* ; Visual Acuity ; Vitrectomy

PURPOSE: To investigate the clinical significance of electroretinographic (ERG) responses, including the photopic negative response parameter, in assessing the progression of diabetic retinopathy. METHODS: Standard flash ERG was tested on 28 normal controls and 143 patients who were diagnosed with diabetes mellitus. Of those, 97 patients had diabetic retinopathy in different stages. Electroretinography was performed according to the International Society for Clinical Electrophysiology of Vision (ISCEV) standards. Amplitudes and implicit times of ERG responses, including the photopic negative response (PhNR), were compared at different stages of diabetic retinopathy. RESULTS: Amplitudes of oscillatory potentials were significantly reduced in mild NPDR. Cone b-wave amplitude, 30--Hz flicker response, and PhNR were significantly reduced in moderate NPDR. CONCLUSIONS: These results suggest that oscillatory potentials are good indicators of retinal function change in the early stage of diabetic retinopathy, and the appropriate results of the cone b-wave, 30-Hz flicker response and PhNR tests are good indicators of moderate NPDR.
Diabetes Mellitus ; Diabetic Retinopathy ; Electrophysiology ; Electroretinography ; Humans ; Retinaldehyde ; Vision, Ocular

PURPOSE: To evaluate the changes in multifocal electroretinogram (mfERG) and optical coherence tomography (OCT) after intravitreal bevacizumab injection in the treatment of age-related macular degeneration (AMD). METHODS: Twenty-one eyes with choroidal neovascularization secondary to AMD were studied before and after intravitreal bevacizumab injection for best corrected visual acuity (BCVA), OCT, and mfERG. RESULTS: The BCVA improved, while central macular thickness and total macular volume in OCT decreased after intravitreal bevacizumab injection (p = 0.03, 0.01, and 0.01, respectively). In mfERG, the amplitude of P1, and implicit time of P1 and N1 indicated a statistically significant improvement of retinal response after intravitreal bevacizumab injection. CONCLUSIONS: There is a potential role for mfERG in evaluating the effect on retinal function of intravitreal bevacizumab injection.
Adult ; Aged ; Angiogenesis Inhibitors/*administration & dosage ; Antibodies, Monoclonal/*administration & dosage ; Choroidal Neovascularization/*drug therapy/*etiology ; Electroretinography/*methods ; Eyeglasses ; Humans ; Intravitreal Injections ; Macular Degeneration/*complications/diagnosis/physiopathology ; Middle Aged ; Retina/drug effects/physiopathology ; Tomography, Optical Coherence ; Visual Acuity