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Laser photocoagulation has become the standard for treatment of retinopathy of prematurity. In general, it has been found to be a safe and effective means of retinal ablation. We report a case of angle-closure glaucoma in an infant after diode laser treatment for retinopathy of prematurity, which required bilateral surgical peripheral iridectomies.
A 41-year-old man had suffered trauma to the right eye 30 years ago. In March 1996, he underwent trabeculectomy and peripheral iridectomy under the diagnosis of open angle glaucoma in the right eye. Autoperimetry at that time revealed visual field constriction. In addition, ocular examination showed that the cup/disc ratio of his right eye was increased. Cataract was diagnosed in September 2002 and cataract extraction was performed on October 22, 2002. Aplastic intravitreal foreign body was detected during the operation. However, preoperative B-scan ultrasonography had failed to detect an intraocular foreign body (IOFB), and the previous fluorescein angiography had shown only retinal pigment epithelium changes. This case reminded us that we should be alert to an occult IOFB in the event of ocular trauma, even if none had been detected during prior imaging examinations.
PURPOSE: To report the treatment of exudative retinal detachment in a patient with nanophthalmos. METHODS: A 46-year-old man with bilateral nanophthalmos suffered from acute angle-closure glaucoma in his left eye. The first day after a peripheral iridectomy an exudative retinal detachment was observed. Two months later a partial thickness sclerectomy with a central sclerostomy, covered by a thin film of absorbable gelatine, was performed in each quadrant of the left eye. RESULTS: The retinal detachment gradually resolved and after eight months the retina was completely reattached. Vision, which had been limited to hand movements, improved to 6/18 with correction. CONCLUSION: Scleral resections are effective in the treatment of nanophthalmic retinal detachment. The use of absorbable gelatine film to cover the sclerectomized area may prevent regeneration of scleral tissue and recurrence of the exudative retinal detachment.
PURPOSE: To investigate the cellular morphology in the subretinal space following transplantation of iris pigment epithelial (IPE) cells from the same eye. METHODS: Following an iridectomy, fresh IPE cells were prepared and no culturing performed. After pars plana vitrectomy, a suspension of autologous IPE cells was injected into the subretinal space in 37 rabbits. The grafts were monitored by ophthalmoscopy and colour fundus photography. Rabbits were sacrificed at 1, 2, 3 and 6 months, respectively, and the eyes examined with light and electron microscopy. RESULTS: The grafted area retained the same configuration over 6 months but then appeared less pigmented. At 1-3 months, the IPE formed one or more contiguous layers on top of native RPE. At 6 months, cells compatible with grafted IPE were present in the subretinal space, often forming monolayer-like chains integrating with the native RPE. Depigmented cells of presumed IPE origin were seen and frequently in association with abundant melanin granules located in the apical portion of adjacent RPE cells. In such areas, large macrophage-like cells were observed. CONCLUSION: Transplanted IPE cells survived for up to 6 months in the subretinal space. Our observations suggest a scenario of remodelling of the cellular layers in the subretinal space over time where grafted IPE cells formed a compound layer with the native RPE. Transplantation of autologous IPE cells may have a potential as a treatment modality in selected cases of age-related macular degeneration.
PURPOSE: To investigate photoreceptor survival in transplantation of non-cultured iris pigment epithelial (IPE) cells to the subretinal space in a prospective experimental study. METHODS: Upper iridectomies were carried out in the right eyes of 37 pigmented rabbits. Suspensions of freshly harvested autologous IPE cells (without culturing) were prepared and injected into the subretinal space of the same eye. Follow-up examinations were carried out using ophthalmoscopy and colour fundus photography. The rabbits were killed at 1, 2, 3 and 6 months, respectively, and the eyes examined with light and electron microscopy. RESULTS: On histological examination, the photoreceptor cells were found to be well-preserved in grafted areas at 1-3 months. At 6 months, the photoreceptors generally disclosed a normal nuclear layer and long outer segments when overlying areas with single cells or clusters of transplanted IPE cells. Multilayers of cells in abundance, including native RPE cells and macrophages (stained with RAM 11), particularly under microfolds of the neural retina, were occasionally associated with photoreceptor damage and nuclear drop out from the outer retinal layer. There was no inflammatory response in the choroid and the choriocapillaris remained patent. CONCLUSION: The experiments show that grafting freshly harvested autologous IPE cells to the subretinal space is feasible and that the photoreceptors generally survive for at least 6 months when overlying the transplanted areas. Multilayers of abundant cells in the subretinal space may induce adverse focal effects on adjacent photoreceptors.
A prospective trial of argon laser trabeculoplasty (ALT) in narrow angle glaucoma (NAG) was undertaken. In eyes with NAG the mechanism of the glaucoma could be a combination of pupil block with subsequent irido-trabecular adhesion and trabecular damage with an increase in outflow resistance. To achieve relief of pupil block, eyes were randomly assigned to treatment with short pulsed laser iridotomy (LI) with the YAG or Dye lasers, or surgical peripheral iridectomy (PI). Alternatively, argon laser iridoplasty (IP) was performed to widen the anterior chamber angle sufficiently to permit ALT. Fifty-two eyes were treated and follow-up was from 12 to 22 months. A high rate of failure to control IOP with topical medication and progression of visual field loss occurred in all treatment groups. Iridoplasty followed by ALT was particularly unsuccessful as, in 50 per cent of cases, progressive synechial closure of the anterior chamber angle occurred following treatment. In eyes treated with PI/LI and ALT, the IOP control was improved in 12 per cent, unchanged in 30 per cent and remained uncontrolled in 58 per cent. By 15 months follow-up, a satisfactory outcome (IOP less than 21 mmHg on topical medication, visual field and acuity stable) was obtained in 24 per cent of the 33 eyes treated with PI/LI and ALT. Thirty-one of these eyes showed visual field loss. Of the 10 eyes that did not receive ALT following PI or LI, 90 per cent had a satisfactory outcome. Eight of these eyes showed little or no visual field loss. The authors conclude that iridoplasty followed by ALT is an unsuitable treatment for eyes with NAG. We further conclude that ALT is unlikely to be of benefit in eyes with NAG and visual field loss, even after pupil block has been relieved. Relief of pupil block alone may help eyes with early NAG without visual field loss.
The eagle retina is bifoveal. The temporal fovea, which can resolve targets subtending half a minute or less must depend upon its peripheral cornea for such sharp resolution. Our studies showed the eagle cornea to be thinner, scatter less light and be more spherical than the human cornea. Further experimental studies determined the resolving power of the human peripheral cornea. Using, normal subjects, pinholes placed at the edge 8 mm dilated pupils yielded 20/30 visual acuity and normal contrast sensitivity measurements. Thus it is recommended that optical iridectomy be considered, in appropriate cases of corneal blindness with patches of clear peripheral cornea when no donor corneal material is available.
We compared 15 patients who had undergone Holmium laser sclerostomy ab externo with 15 who had had trabeculectomy. In the short term, laser sclerostomy led to adequate control of intraocular pressure, but in the longer term it compared unfavourably with trabeculectomy in terms of efficacy, complications and reoperation rate. At 1 year follow-up, 8 patients in the laser group had had to undergo a second operation compared with none in the control trabeculectomy group, and 7 were still on glaucoma medication compared with 2 in the control group. Iris prolapse into the internal sclerostomy ostium within 2 months accounted for most failures, and was only partially amenable to Nd:YAG peripheral iridectomy. This common complication seems to be related to anterior chamber depth. There also appears to be a tendency for blockage of the sclerostomy with cellular or fibrinous debris. Recent literature is reviewed and modifying strategies discussed.
Varix of the iris as a solitary primary lesion is rare. We report a 31-year-old Indian man with an iris varix who developed recurrent haemorrhages into the anterior chamber which led to secondary glaucoma. An iridectomy was performed and the diagnosis was confirmed histologically. There has been no recurrence of the lesion 3 years after surgery.
Evaluation of 4-month-old girl who presented with congenital cataracts revealed heterochromia iridis, fundus hypopigmentation, residual white forelock and sensory neural hearing loss--findings consistent with Waardenburg syndrome type II. Bilateral peripheral iridectomies performed at lensectomy provided tissue for evaluation. Light microscopy revealed fewer melanocytes in the blue iris than in the brown. Electron microscopic examination showed a significant (p = 0.0001) reduction in melanosome size in the blue iris, and the nerve endings contained fewer vesicles. A defect in neural crest cell migration and melanin synthesis may be responsible for the heterochromia iridis seen in Waardenburg syndrome type II.
We show that iris tissue in the adult rat eye, which is embryonically related to the neural retina, can generate cells expressing differentiated neuronal antigens. In addition, the Crx gene transfer induced the specific antigens for rod photoreceptors in the iris-derived cells, which was not seen in the adult hippocampus-derived neural stem cells. Our findings demonstrate a remarkable plasticity of adult iris tissue with potential clinical applications, as autologous iris tissue can be feasibly obtained with peripheral iridectomy.
PURPOSE: To evaluate the safety and efficacy of surgical implantation of prosthetic iris devices in patients with iris deficiency. METHODS: Nine patients with traumatic iris defects, congenital aniridia or iris coloboma, and surgical or optical iridectomies were included in a noncomparative case series. Cataract surgery with intraocular lens and prosthetic iris implantation was performed in 10 eyes. The visual acuity, subjective degree of glare disability, postoperative anatomic results, and intraoperative and postoperative complications were evaluated. RESULTS: The mean follow-up was 17.75 months (range 4-48 months). Best-corrected visual acuity improved in nine of 10 eyes (90%) and remained unchanged in one eye. Glare subjectively improved in four of five eyes (80%) of patients complaining of glare preoperatively. All eyes achieved the desired anatomic result. Intraoperative complications included one anterior capsular tear. Postoperative complications included a short period of mild postoperative anterior uveitis in four eyes. Secondary glaucoma was absent. CONCLUSION: In patients with iris deficiency, implantation of prosthetic iris device, and intraocular lens implant following cataract surgery appears to be safe and effective in reducing glare disability and improving visual outcomes.
PURPOSE: Glaucoma is the second cause, after cataract, of world blindness. Approximately half is thought to be primary angle-closure glaucoma (ACG). This review asks whether ACG can be prevented on a population basis. METHODS AND POPULATIONS: Review of published information from the Inuit of Greenland, Canada and Alaska, and descriptions of recent studies in Asian populations in Mongolia, China and South-East Asia. RESULTS: The Greenland Inuit have the shallowest anterior chamber depths (ACDs) so far recorded. The proportion of blindness due to ACG was reduced from 64% to 9% over 37 years by systematic optical measurement of central ACD and the van Herick test in the older Inuit, followed by gonioscopy and prophylactic iridectomy or laser iridotomy when indicated. In Mongolia, ultrasound measurement of central ACD had good sensitivity and specificity as a screening test. A randomized controlled trial of screening and prophylactic laser is being completed. In China and South-East Asia, the mechanism of angle closure appears to be more varied and complex and its detection may require more elaborate imaging. CONCLUSIONS: The mechanism of angle closure and potential for prevention by screening are likely to have to be determined specifically for each population at risk.
PURPOSE: To investigate the causes of glaucoma in children following removal of cataracts. METHODS: In total, 24 patients (37 eyes) with uncomplicated congenital cataracts who developed glaucoma following cataract removal were studied retrospectively. Cataract morphology, surgical technique, postoperative complications, time to glaucoma onset, gonioscopic findings, the presence of microcornea, and the histopathologic characteristics of the filtration angle in one case were the studied parameters. RESULTS: We found a bimodal onset of glaucoma. Early-onset glaucoma occurred at a mean age of 6 months in 15 eyes and delayed-onset glaucoma at a mean age of 12 years in 22 eyes. Early-onset glaucoma was significantly (P=0.018) more likely to be due to angle closure. With delayed-onset glaucoma, the filtration angle is open in 86% of eyes and significantly (P=0.006) more eyes in the delayed-onset group had microcornea. CONCLUSIONS: Performing cataract surgery very early in life in microphthalmic eyes and leaving residual lens material increases the risk for glaucoma. We recommend a prophylactic iridectomy in eyes at risk for pupillary block. Eyes with delayed-onset glaucoma have open filtration angles but with findings consistent with incomplete development of filtration structures. Early age at cataract extraction and microcornea are risk factors for delayed-onset glaucoma.
BACKGROUND: A number of authors have documented the decrease in the rate of glaucoma drainage surgery, felt to be owing to increased medical therapy options. There has also been an increase in cataract extraction. The aim of this study was, using the NHS Hospital Episode Statistics (HES), to attempt to confirm these trends and to examine the possibility that these trends are not necessarily independent. METHODS: The HES was accessed for the main glaucoma procedures between 1998 and 2004 and for cataract operations performed over the same time period. Diagnostic data were also extracted from the HES data for glaucoma. Figures for the changes in glaucoma medications were obtained from pharmaceutical data. RESULTS: Over the period that the data are available, trabeculectomy numbers have reduced by 51%, laser trabeculoplasty by 60%, and laser peripheral iridectomy (PI) by 30%. Cataract extractions have increased by 52%. Medical treatments, especially prostaglandin use, have increased. The number of admissions for acute glaucoma did not increase. CONCLUSIONS: The figures indicated a decrease in glaucoma drainage surgery and an increase in cataract extraction-consistent with other studies. More surprisingly, there was no increase in diagnosis of angle closure glaucoma or laser PIs within the figures and we suggest this may in part be related to the increase in cataract extraction. We speculate that this may also partly be responsible for the reduction in trabeculectomies. Although the HES data are a potentially rich source of information, there are potential inaccuracies in the data, which means interpretations must be made with caution.
PURPOSE: To evaluate the long-term results of Erbium YAG-laser-assisted deep sclerectomy (DS). In this procedure, the delicate dissection of a deep corneoscleral lamella is greatly simplified by using the Erbium YAG-laser. METHODS: Data of 14 consecutive patients (10 male, four female, age 67.7+/-10.4 years), who underwent surgery from 1999 to 2000 were analysed retrospectively. The procedure was begun as a standard DS. The deep corneoscleral lamella was dissected with a pulsed Erbium YAG-laser (energy: 40-100 mJ, frequency: 5-10 Hz). Schlemm's canal was unroofed and the lamella thinned until aqueous percolated continuously through the membrane. RESULTS: The mean follow-up time was 50.4+/-6.8 months. The mean preoperative intraocular pressure (IOP) was 37.7+/-10.5 mmHg. The mean postoperative IOP was 16.1+/-3.9 mmHg at 1 month, 15.1+/-4.3 mmHg at 3 months, 16.4+/-4.5 mmHg at 12 months, and 17.6+/-8.7 mmHg at 50.5 months. The complete success rates (IOP< or =21 mmHg+IOP reduction > or =20% without glaucoma medication) were 83.3% at 3 months and 50% at 12 and 50.5 months. Rates for qualified success (IOP< or =21 mmHg+IOP reduction > or =20% with glaucoma medication) were 91.7% at 3 months, 92.9% at 12 months, and 78.6% at 50.5 months. The number of glaucoma medications was reduced from 3.07+/-0.92 preoperatively to 1.14+/-1.41 at 50.5 months. A single case of anterior-chamber penetration, requiring iridectomy, was the only intraoperative complication. CONCLUSIONS: Erbium YAG-laser-assisted DS has the advantage of a greatly simplified dissection, while offering a successful long-term IOP control comparable to conventional DS.
BACKGROUND: The records of the University Eye Clinic are almost completely preserved at the historical archive of the University of Tübingen since 1865 and shell now be reduced. MATERIALS AND METHODS: 150 records from the historical archive of the University of Tübingen were selected. We were interested in those patients treated for the first time at the University Eye Clinic between 1895 and 1899. Only diseases of the optic nerve, the uveal tract and the retina were considered. The records were distributed into groups following historical classification and statistics of the same period. These statistics were also used to compare our selection with all patients treated. For information about frequency, diagnostics and therapy a questionnaire was developed. RESULTS: Glaucoma: The data of the subgroup "Glaucoma simplex" showed high correspondence with the historical data regarding the frequency (24.3 vs. 25.5%). The data of the subgroup "Glaucoma secundaria" differed (34.5 vs. 25.5%). Testing the visual acuity was the first step of examination here and in all groups (100%). Measurement of intraocular pressure with digital palpation followed (86.3%). First of all Eserin eye drops were applicated (76.5%). Iritis: The frequency of acute iritis was 16.8 vs. 25.0%, and of chronic iritis 59.6 vs. 52.2%. As typical symptoms ciliar injections, fixed anisocore pupil and exudation were often seen (80.0%). Chronic iritis showed as typical symptom posterior synechia (80.9%). Atropin eye drops were firstly applied in acute iritis (100%), chronical iritis was treated by iridectomy (57.1%). Myopia: In all subgroups our data differed from the historical data. Staphyloma posticum was the characteristic diagnosis (65.8%). Myopia was treated by decision of the lens. Retinal detachment: The frequency 37.2 vs. 28.0%. In nearly all cases retinal detachment was described after ophthalmoscopic examination (92.8%). The first therapeutical step was to keep the patients staying in bed (53.8%). CONCLUSIONS: As expected, diagnostic and therapeutical options were strongly limited in Tübingen 100 years ago. Nevertheless, therapeutic successes were achieved in certain cases.
BACKGROUND: Subretina transplantation of epithelium may be a therapeutic option for surgical treatment of age-related macular degeration (AMD). Various experimental data have demonstrated that homologous transplantation of retinal pigment epithelium (RPE) can prevent photoreceptor deterioration. However, most investigators experienced immunogenic graft rejection when using homologous pigmented cells for grafting. Autologous cells were soon considered as an alternative for subretinal grafting. Particularly iris pigment epithelium (IPE) appeared suitable to replace homologous RPE for it embryogenetic similarity and its simple availability. Recent studies have shown, that IPE is capable of taking over functions of RPE in maintaining retinal metabolism. the purpose of this study was to evaluate if autologous IPE cells would survive when being transplanted subretinally. In addition, immunogenic reponses to the presence of "foreign" iris pigment cells needed to be excluded. MATERIALS AND METHODS: Iris tissue was obtained by peripheral iridectomy in the anesthetized pig. Sheets of pigment iris epithelium were separated from the specimens and transferred into tissue culture. After the cells had been grown to confluency, cell suspensions were injected into the subretinal space of the donor animal's fellow eye. After 4 weeks, the grafted eye was enucleated and examined histologically.. RESULTS: The histological exam revealed that the graft cells had survived in the subretinal space. No evidence of immunogenic rejection was observed. CONCLUSION: Autologous IPE-cells can survive in the host's sub-retinal space without creating inflammatory reactions. Transplanted IPE appears to interact with photoreceptor outer segments.