Nobuchika Ogino

Vitrectomy for diffuse macular edema in cases of diabetic retinopathy

PURPOSE To ascertain the effects of posterior vitreous detachment for diffuse diabetic macular edema. METHODS We performed vitrectomy on 58 eyes of 41 consecutive patients with diabetic macular edema without posterior vitreous detachment. Follow-up was done at 12 months postoperatively. RESULTS In 57 of 58 eyes after vitrectomy and posterior vitreous detachment, macular edema resolved, and diffuse fluorescein leakage disappeared in 35 of 36 eyes examined at the 12th month. Visual improvement was statistically significant (P < .0001, paired t test). CONCLUSION In eyes with diffuse diabetic macular edema and without posterior vitreous detachment, vitrectomy with posterior vitreous detachment may be effective.

Vitreous surgery with and without internal limiting membrane peeling for macular hole repair.

Purpose: To compare surgical results for idiopathic macular holes with and without internal limiting membrane (ILM) peeling in a series of consecutive patients during an 8-year period. Methods: A retrospective, nonrandomized, comparative trial. Four hundred seventeen eyes with macular holes without ILM peeling were compared with 175 eyes with ILM peeling. All eyes underwent pars plana vitrectomy with intravitreous gas, followed by head-down positioning. No adjunctive therapies were used. Comparison of closure and reopening rates and visual acuity with and without ILM peeling was analyzed. Results: Initial success rate significantly improved from 81% to 92% with ILM peeling. ILM peeling significantly improved the initial success rates in all categories of preoperative features. Reopening rates significantly decreased from 7% to 0.6% with ILM peeling. Among successful cases, line improvement was 6.0 in ILM-reserved eyes and 5.8 in ILM-peeled eyes. Among all cases, line improvement was 5.4 in ILM-reserved eyes and 5.7 in ILM-peeled eyes. Initial success rate of holes measuring more than 400 &mgr;m was significantly less than that of holes measuring less than 400 &mgr;m with or without ILM peeling. Initial success rate of holes older than 6 months old was significantly less than that for holes less than 6 months old without ILM peeling. Conclusions: Internal limiting membrane peeling shows high closure and low reopening rates in macular hole surgery. ILM peeling is beneficial in older holes but is limited in larger holes. ILM peeling does not significantly improve visual acuity.

Müller cells in detached human retina express glial fibrillary acidic protein and vimentin

We investigated the expression of vimentin and glial fibrillary acidic protein (GFAP) within Müller cells in normal human retinas and in detached human retinas of proliferative vitreoretinopathy (PVR) cases using the immunogold method. Muller cells in normal retinas showed vimentin immunoreactivity and faint GFAP immunoreactivity; however, in detached retinas they showed distinct GFAP immunoreactivity as well as vimentin immunoreactivity. Immunoelectron microscopic observation revealed that intermediate filaments (IF) within Müller cells in normal retinas showed vimentin immunoreactivity and that those within Müller cells in detached retinas showed both vimentin and GFAP immunoreactivity. Double staining for vimentin and GFAP showed that in detached retinas, these two protein immunoreactivities were observed in the same filaments. These results indicate that IF of human Müller cells consist of vimentin under normal conditions and that Müller cells in detached retinas contain different IF, which consist of vimentin and GFAP.

Phagocytic Activity of Cultured Retinal Pigment Epithelial Cells from Chick Embryo: Inhibition by Melatonin and Cyclic AMP, and Its Reversal by Taurine and Cyclic GMP

Cultured chick retinal pigment epithelial cells phagocytosed polystyrene latex particles. The phagocytosis was inhibited very specifically by melatonin, which attained 50% inhibition at about 10(-16) M. Other indole compounds such as 5-methoxytryptophol, 5-hydroxytryptophol, 6-hydroxymelatonin, N-acetylserotonin, 5-methoxytryptamine and serotonin were also inhibitory although their effects were less than 1/10,000 that of melatonin. Possible retinal neurotransmitters, acetylcholine, gamma-aminobutyric acid, glycine, dopamine, aspartic acid and glutamic acid, had no or only a minimum inhibitory effect, and was also the case for prostaglandin D2, E2, F2 alpha, and I2. Taurine was not inhibitory at all. Among nucleotides, cyclic AMP specifically inhibited phagocytosis, giving 50% inhibition at about 10(-11) M. Melatonin inhibition was increased by copresence of isobutylmethylxanthine. Inhibition by either melatonin or cyclic AMP was reversed by dibutyryl cyclic GMP. The reversal was observed also with compounds which were expected to increase intracellular cyclic GMP. Prostaglandin D2 reversed inhibition in both cases, but its effect was incomplete and per se it had an inhibitory effect. Melatonin derivatives reversed inhibition by melatonin alone but not inhibition by cyclic AMP. Taurine efficiently reversed both kinds of inhibition. Other possible neurotransmitters were ineffective. Taurine was thus the most effective of these compounds. We suggest the following hypothetic control mechanism of phagocytic activity of the pigment epithelial cells: melatonin and cyclic AMP are intercellular and intracellular signals, respectively, of stopping phagocytosis, while taurine and cyclic GMP are intercellular and intracellular signals, respectively of cancelling this stop signal. Phagocytic activity of chick retinal pigment epithelial cells might be regulated by the concentration ratio of melatonin to taurine in the interphotoreceptor space.

Quantitative Analysis of Lens Changes After Vitrectomy by Fluorophotometry

We measured the amount of autofluorescence in the lens to evaluate quantitatively lens changes after vitrectomy. Thirteen phakic patients, ranging in age from 12 to 75 years, were studied after unilateral vitrectomy, with a follow-up period of more than two years (range, 26 to 55 months). Autofluorescence in the lens was measured at the center along the ocular axis by fluorophotometry. Lens autofluorescence in the eyes that underwent vitrectomy was significantly higher than in the contralateral eyes that were not operated on (P = .0003). The increase of autofluorescence was correlated significantly with the age at time of vitrectomy (P = .0008). There was no correlation between the increase in autofluorescence and the length of postoperative follow-up or the use of air during vitrectomy. Based on these results, we believe that oxidation of lens proteins intraoperatively may be one of the causes of development of nuclear cataract after vitrectomy.

Long-term follow-up of vitrectomy for diffuse nontractional diabetic macular edema.

Purpose: To report the long-term results of pars plana vitrectomy for diffuse nontractional diabetic macular edema. Design: Interventional, retrospective, consecutive case series. Methods: Clinical records of 332 consecutive patients (496 eyes) with diabetic macular edema without a thickened and taut posterior hyaloid on contact lens examination were reviewed. Four hundred eighty-six eyes of 326 consecutive patients were included in this study. All patients underwent pars plana vitrectomy with the creation of a posterior vitreous detachment by one surgeon. Simultaneous phacoemulsification with intraocular lens implantation was performed on 456 phakic eyes. Internal limiting membrane peeling was performed on 178 (36.6%) of 486 eyes. The main outcome measured was best-corrected visual acuity results during follow-up periods. Results: Postoperative follow-up ranged from 12 to 170 months (mean, 74.0 months). Five year follow-up data were available for 356 (71.8%) of 496 eyes. Mean preoperative best-corrected visual acuity significantly increased from 0.19 (20/105) to 0.32 (20/63) at 1 year after surgery (P < 0.0001), and 0.30 (20/67) at the final visit (P < 0.0001). The final best-corrected visual acuity improved in 256 (52.7%) of the 486 eyes, remained unchanged in 152 eyes (31.3%), and worsened in 78 eyes (16.0%). Postoperative major complications included neovascular glaucoma in 19 eyes (3.9%), recurrent vitreous hemorrhage in 10 eyes (2.1%), hard exudate deposits in the center of the macula in 21 eyes (4.2%), and glaucoma in 22 eyes (4.5%). Conclusions: Pars plana vitrectomy with and without internal limiting membrane peeling appears to be beneficial in eyes with diffuse nontractional diabetic macular edema, and its effectiveness is maintained long term.

Vitreous surgery for traumatic macular holes.

PURPOSE To review the anatomic and visual outcomes of a series of patients with traumatic macular holes who underwent vitreous surgery without adjunctive therapy. METHODS We performed a retrospective chart review of 23 patients who underwent vitrectomy, fluid-gas exchange, and sulfur hexafluoride gas tamponade for traumatic macular holes. Anatomic success rate and final visual improvement after the surgery were studied. RESULTS Medical records of 23 patients (23 eyes) who underwent this procedure were reviewed. Closure of the macular hole was achieved in 16 (70%) eyes with one surgery and in 22 (96%) of the 23 eyes with two surgeries. The mean best-corrected preoperative visual acuity was 20/160, and postoperative visual acuity was 20/60 with a mean (+/- standard deviation) follow-up of 23+/-13 months (range 3-56 months). Fourteen (61 %) of the 23 eyes achieved a best-corrected postoperative visual acuity of 20/60 or better, and 11 (48%) of the 23 eyes achieved 20/40 or better. Twenty (87%) of the 23 eyes achieved at least two lines of visual improvement. CONCLUSIONS Vitreous surgery without adjunctive therapy for traumatic macular holes can lead to anatomic success and visual acuity improvement in most eyes.

Long-term outcomes of internal limiting membrane peeling with and without indocyanine green in macular hole surgery.

Purpose: To compare the long-term anatomic closure rate and visual outcome in patients who underwent internal limiting membrane (ILM) peeling with and without indocyanine green (ICG) dye staining for idiopathic macular hole repair. Design: Retrospective, nonrandomized, comparative study of consecutive case series. Methods: A total of 190 eyes of 182 patients with idiopathic macular holes underwent macular hole repair between March 1998 and June 2003. Surgery consisted of pars plana vitrectomy, lensectomy if phakic, ILM peeling, intravitreal gas tamponade, and 1 week’s face-down positioning. In the initial 94 consecutive eyes, ILM peeling was performed without adjuvants (non-ICG group). The subsequent 96 eyes underwent surgery with ICG-stained ILM peeling (ICG group), in which the ILM was stained with intravitreal application of 0.1 to 0.2 mL of 0.1% ICG solution. Results: Two groups of patients had comparable clinical backgrounds preoperatively. Mean follow-up time was 30.7 months in non-ICG group and 26.2 months in ICG group. Anatomic closure of the macular hole was achieved in 99% of the cases in both groups, with both groups showing statistically significant visual improvement. There was no statistically significant difference in visual acuity between the two groups at each follow-up visit. There were also no intraoperative or postoperative complications attributed to the use of ICG. Conclusions: Long-term follow-up of patients undergoing ILM peeling for idiopathic macular hole repair shows equivalent anatomic and visual outcomes with and without the use of ICG.

Juvenile retinal detachment

The features and prognoses of 802 cases (908 eyes) of retinal detachment from 8 months to 19 years of age were studied with the patients divided into three age groups: 65 eyes in group I (0-9), 259 eyes in group II (10-14), and 584 eyes in group III (15-19). Eyes in group I were different from the others in many respects. In group I, traumatic detachments, preoperative complications, four-quadrant detachments, and eyes with undetected breaks were more frequent, and the prognosis was worse than in the other groups. Holes with lattice degenerations were most frequent in group III eyes having no history of trauma. Group III resembled adult retinal detachment and group II was thought to be the transitional type.

Isolation of an activator for prostaglandin hydroperoxidase from bovine vesicular gland cytosol and its identification as uric acid

Abstract The enzymatic conversion of prostaglandin G 1 to H 1 was stimulated by an activator present in the cytosol of bovine vesicular gland. The activator was purified by Sephadex G-25 gel filtration and Dowex 1 column chromatography. The purified activator was identified to be uric acid by thin layer chromatography, ultraviolet and infrared absorption spectroscopy and combined gas chromatography-mass spectroscopy. Among various purine compounds tested, only uric acid and 2,8-dihydroxyadenine were active.