Generation of Retinal Pigmented Epithelium-Like Cells from Pigmented Spheres Differentiated from Bone Marrow Stromal Cell-Derived Neurospheres

BACKGROUND: Retinal degeneration causes blindness, and cell replacement is a potential therapy. The purpose of this study is to formation of pigmented neurospheres in a simple medium, low-cost, high-performance manner over a short period of time while expressing markers of RPE cells and the activation of specific genes of the pigment cells. Also, these neurospheres have the ability to produce a monolayer of retinal pigment epithelium-like cells (RPELC) with the ability of photoreceptor outer segment phagocytosis. METHODS: BMSC were isolated from pigmented hooded male rats and were immunoreactive to BMSC markers, then converted into neurospheres, differentiated into pigmented spheres (PS), and characterized using Retinal pigment epithelium-specific 65 kDa protein (RPE65), Retinaldehyde-binding protein 1 (CRALBP) and orthodenticle homeobox 2 (OTX2) markers by immunocytochemistry, RT-PCR and RT-qPCR. The PS were harvested into RPELC. The functionality of RPELC was evaluated by phagocytosis of fluorescein-labeled photoreceptor outer segment. RESULTS: The BMSC immunophenotype was confirmed by immunostained for fibronectin, CD90, CD166 and CD44. These cells differentiated into osteogenic and lipogenic cells. The generated neurospheres were immunoreactive to nestin and stemness genes. The PS after 7–14 days were positive for RPE65 (92.76–100%), CRALBP (95.21–100%) and OTX2 (94.88–100%), and after 30 days RT-PCR, qPCR revealed increasing in gene expression. The PS formed a single layer of RPELC after cultivation and phagocyte photoreceptor outer segments. CONCLUSION: Bone marrow stromal stem cells can differentiate into functional retinal pigmented epithelium cells in a simple, low-cost, high-performancemanner over a short period of time. These cells due to expressing theRPELCgenes andmarkers can be used in cell replacement therapy for degenerative diseases including age-relatedmacular degeneration as well as retinitis pigmentosa.

Predictors and Outcomes of Vitrectomy and Silicone Oil Injection in Advanced Diabetic Retinopathy

PURPOSE: To evaluate visual and anatomical results and identify factors that influence vitrectomy and silicone oil (SO) injection outcomes in proliferative diabetic retinopathy (PDR). METHODS: This retrospective study included 236 eyes with PDR that were undergoing vitrectomy and SO injection with >3-month follow-up. The primary outcomes were final best-corrected visual acuity (BCVA) and retinal attachment rate. RESULTS: At the final visit (mean, 88 ± 58 weeks), complete, partial, and no retinal attachment were observed in 86.9%, 10.6%, and 2.5% of patients, respectively. A total of 155 eyes had experienced SO removal, while 81 had SO in place. The mean initial BCVA was 1.9 ± 0.7 logarithm of the minimum angle of resolution (logMAR) and significantly improved to 1.7 ± 0.8 logMAR (p = 0.001). Initial macular detachment (adjusted odds ratio [AOR], 0.25), development of iatrogenic break (AOR, 0.25), and use of heavy SO (AOR, 0.13) were independently associated with a lower risk of final retinal attachment, and SO removal was associated with a higher incidence (AOR, 7.55). Better baseline BCVA was associated with a higher risk of final BCVA ≥20 / 200. CONCLUSIONS: Despite an encouraging outcome based on anatomical data in advanced PDR treated with vitrectomy and SO, the functional prognosis was not satisfying for patients. Eyes with better vision at baseline had a more favorable prognosis, whereas eyes with initial macular detachment, intraoperative iatrogenic break, or heavy SO showed more unfavorable outcomes. In selected cases, extending the time of SO use did not worsen the prognosis.

Childhood pars planitis; clinical features and outcomes

To evaluate the demographic and clinical features of childhood pars planitis, and to determine the therapeutic and visual outcomes of the disease. Medical records of pediatric patients [less than 16 years of age at diagnosis] with pars planitis and at least 6 months of follow-up who were referred to Labbafinejad Medical Center, Tehran, Iran over a 22 year period were reviewed. Overall, 117 eyes of 61 patients including 51 [83.6%] male subjects were included. Mean age at the time of diagnosis was 7.8 +/- 3.2 [range, 3-16] years. Mean best corrected visual acuity [BCVA] was 0.88 +/- 0.76 logMAR at presentation which improved to 0.39 +/- 0.51 logMAR at final visit [P<0.001]. Endotheliitis was present in 23 [19.6%] eyes and was significantly more prevalent in subjects younger than 9 years [P=0.025]. Cataract formation [41.9%] and cystoid macular edema [19.7%] were the most prevalent complications. Univariate regression analysis showed that better baseline visual acuity [OR=0.38, 95%CI 0.21-0.70, P=0.002], age older than 5 years at disease onset [OR=0.36, 95%CI 0.14-0.9, P=0.029], absence of endotheliitis [OR=0.39, 95%CI 0.15-0.99, P-0.047] and female gender [OR=3.77, 95%CI 1.03-13.93, P=0.046] were significantly associated with final BCVA of 20/40 or better. Childhood pars planitis was much more common among male subjects. Endotheliitis may be a sign of inflammation spillover and is more prevalent in younger patients. Visual prognosis is favorable in most patients with appropriate treatment

Retinal pigment epithelium culture; a potential source of retinal stem cells

To establish human retinal pigment epithelial [RPE] cell culture as a source for cell replacement therapy in ocular diseases Human cadaver globes were used to isolate RPE cells. Each globe was cut into several pieces of a few millimeters in size. After removing the sclera and choroid, remaining tissues were washed in phosphate buffer saline and RPE cells were isolated using dispase enzyme solution and cultured in Dulbecco's Modified Eagle's Medium: Nutrient Mixture F-12 supplemented with 10% fetal calf serum. Primary cultures of RPE cells were established and spheroid colonies related to progenitor/stem cells developed in a number of cultures. The colonies included purely pigmented or mixed pigmented and non-pigmented cells. After multiple cellular passages, several types of photoreceptors and neural-like cells were detected morphologically. Cellular plasticity in RPE cell cultures revealed promising results in terms of generation of stem/progenitor cells from human RPE cells. Whether the spheroids and neural-like retinal cells were directly derived from retinal stem cells or offspring of trans-differentiating or de-differentiating RPE cells remains to be answered

Characteristics and surgical outcomes of rhegmatogenous retinal detachment following myopic LASIK

To describe the clinical features and surgical outcomes of rhegmatogenous retinal detachment [RRD] following myopic laser in situ keratomileusis [LASIK]. In a retrospective, non-comparative case series, 46 eyes that had undergone vitreoretinal surgery for management of RRD following myopic LASIK were identified. Data was reviewed with emphasis on characteristics of the RRD, employed surgical techniques, and anatomic and visual outcomes. Mean pre-LASIK myopia was -9.7 +/- 3.9 [range -4.00 to -18.00] diopters [D]. Mean interval between LASIK and development of RRD was 11.6 +/- 11.2 months. Posterior vitreous detachment was present in 44 eyes [95.6%]. The retinal breaks included flap tears in 36 [78.3%] eyes, giant tears in 8 [17.4%] eyes and atrophic holes in 2 [4.3%] eyes. In eyes with flap tears, the breaks were multiple, large or posterior to the equator in 24 [66.7%] eyes. Retinal breaks were related to lattice degeneration in 20 [43.5%] eyes of which, three had history of prophylactic barrier laser photocoagulation. Scleral buckling was performed as the initial procedure in 32 [69.6%] eyes and primary vitrectomy was undertaken in 14 [30.4%] eyes. The initial surgical procedure failed in 14 [30.4%] eyes due to proliferative vitreoretinopathy [PVR]. Retinal reattachment was finally achieved in 43 [93.4%] eyes. Postoperative visual acuity >/= 20/40 and >/= 20/200 was achieved in 16 [34.8%] and 25 [54.3%] eyes, respectively. Post-LASIK retinal detachment has a complex nature in eyes with moderate to high myopia. The retinal detachment is complex in terms of size, number and location of retinal breaks, is associated with a high rate of PVR and entails unfavorable visual outcomes

Intravitreal bevacizumab versus combined bevacizumab and triamcinolone acetonide for neovascular age-related macular degeneration

To compare the short-term outcomes of intravitreal bevacizumab [IVB] with the combination of IVB and intravitreal triamcinolone acetonide [IVB/IVT] for treatment of neovascular age-related macular degeneration [AMD]. This randomized clinical trial was performed on 92 eyes of 90 patients with subfoveal and juxtafoveal choroidal neovascularization [CNV] secondary to AMD. The eyes were randomly assigned to receive IVB 1.25 mg alone [53 eyes] or in combination with IVT 2 mg [39 eyes]. Best-corrected visual acuity [BCVA] and fundus autofluorescence were assessed, and fluorescein angiography [FA] and optical coherence tomography [OCT] were performed at baseline and repeated 6 weeks after treatment. Mean age was 70.6 +/- 8.7 [range 50-89] years and 57.7% of the patients were male. BCVA improved from 1.03 +/- 0.40 to 0.93 +/- 0.38 logMAR [P=0.001] in the IVB group and from 1.08 +/- 0.33 to 0.91 +/- 0.38 logMAR [P=0.008] in the IVB/IVT group. There was a trend toward greater visual improvement with combined therapy [P=0.06]. BCVA improvement was greater in eyes with +1 versus those with +2 [P=0.049] and +3 [P < 0.001] fundus autofluorescence at baseline. Mean decrease in central macular thickness was 113 +/- 115 micro m [P < 0.001] in the IVB group versus 53.96 +/- 125 micro m [P=0.008] in the IVB/IVT group with no intergroup difference [P=0.38]. FA showed decreased leakage in 57.4%, increased leakage in 12.8% and no change in 29.8% of patients in the IVB group. Corresponding figures were 60.0%, 5.7% and 34.3% in the IVB/IVT group [P=0.556]. Addition of triamcinolone acetonide to bevacizumab for treatment of neovascular AMD does not seem to significantly increase its short-term efficacy. More severe fundus autofluorescence appears to be predictive of poorer response to treatment

Early onset optic neuritis following measles-rubella vaccination

To report two cases of optic neuritis with onset less than 24 hours following measles-rubella [MR] vaccination. Two teenage patients developed acute optic neuritis 6 to 7 hours after MR booster vaccination. The first patient demonstrated bilateral papillitis and severe visual loss but improved significantly with pulse intravenous steroid therapy with methylprednisolone 500 mg/day. The second patient had unilateral retrobulbar optic neuritis and demonstrated excellent visual recovery without intervention. Acute optic neuritis is a rare complication of MR vaccination and may occur early after immunization

Diabetic Macular Edema Before and After Intravitreal Triamcinolone Injection

PURPOSE: To compare intravitreal triamcinolone acetonide (IVT) versus natural course in refractory diabetic macular edema. METHODS: In a prospective interventional case series, twenty five eyes with refractory DME which had been allocated to the sham group of a previous clinical trial underwent new examination and optical coherence tomography about 9 months after their first enrollment. Twenty eyes that met the inclusion criteria, visual acuity (VA) 200 micrometer, were treated by 4 mg IVT. Evaluations were repeated at 2 and 4 months post-injection to imitate the similar examination intervals after sham injection. Corrected visual acuity and macular thickness changes following IVT were compared to the corresponding changes after sham injection (the natural course). RESULTS: Visual acuity changes within and between each period were not statistically significant. Visual acuity decreased 0.08 & 0.09 logMAR by 2 months and 0.06 & 0.04 logMAR by 4 months after sham and IVT injections, respectively. The changes of macular thickness after IVT and sham intervention were not meaningful either. However, the difference between thickness changes by 4 months (52+/-50 micrometer increase after sham vs. 262+/-115 micrometer reduction after IVT) was significant (P=0.014). CONCLUSIONS: Concerning macular thickness, IVT has beneficial effect on refractory diabetic macular edema as opposed to observation. However, considering visual acuity, it does not induce significant difference in comparison to the natural course of the disease.

Diabetic Macular Edema Before and After Intravitreal Triamcinolone Injection

PURPOSE: To compare intravitreal triamcinolone acetonide (IVT) versus natural course in refractory diabetic macular edema. METHODS: In a prospective interventional case series, twenty five eyes with refractory DME which had been allocated to the sham group of a previous clinical trial underwent new examination and optical coherence tomography about 9 months after their first enrollment. Twenty eyes that met the inclusion criteria, visual acuity (VA) 200 micrometer, were treated by 4 mg IVT. Evaluations were repeated at 2 and 4 months post-injection to imitate the similar examination intervals after sham injection. Corrected visual acuity and macular thickness changes following IVT were compared to the corresponding changes after sham injection (the natural course). RESULTS: Visual acuity changes within and between each period were not statistically significant. Visual acuity decreased 0.08 & 0.09 logMAR by 2 months and 0.06 & 0.04 logMAR by 4 months after sham and IVT injections, respectively. The changes of macular thickness after IVT and sham intervention were not meaningful either. However, the difference between thickness changes by 4 months (52+/-50 micrometer increase after sham vs. 262+/-115 micrometer reduction after IVT) was significant (P=0.014). CONCLUSIONS: Concerning macular thickness, IVT has beneficial effect on refractory diabetic macular edema as opposed to observation. However, considering visual acuity, it does not induce significant difference in comparison to the natural course of the disease.

Intravitreal Triamcinolone Reinjection for Refractory Diabetic Macular Edema

PURPOSE: To evaluate the effect of intravitreal triamcinolone acetonide (IVT) reinjection on clinical and optical coherence tomographic features in refractory diabetic macular edema. METHODS: In a prospective interventional case series, all IVT treated patients enrolled in a previous clinical trial were recalled to have a new ophthalmologic examination and optical coherence tomography (OCT) performed. Eyes found suitable for reinjection received 4 mg IVT. Complete clinical examination and OCT were repeated at 2 and 4 months post-injection. The changes were statistically analyzed using a paired t test and were compared to the results of the first injections. RESULTS: Of all returning patients, 12 cases with complete records were considered candidates for reinjection. Visual acuity (VA) changes were not significant after the first and second interventions, although there was a relative improvement (0.14 logMAR) 2 months after the first injection. Reductions of central macular thickness (CMT) were 43+/-69 micrometer, and 40+/-69 micrometer after the first injection and 27+/-48 micrometer, 49+/-58 micrometer after the reinjection at 2 and 4 months, respectively. None of the mentioned changes was significant. After the second injection, however, intraocular pressure was elevated at both 2 and 4 months (3.6 and 2.4 mmHg respectively, P<0.05). Two months after the first administration, intraocular pressure was found to be raised significantly (5.58 mmHg, P=0.001). CONCLUSIONS: The transient beneficial effects of IVT on diabetic macular edema are not repeated with second injections. However, IVT-related ocular hypertension is more persistent after reinjection.

Outcomes of surgical treatment for retinal detachment in highly myopic eyes with macular hole

To determine the type and outcome of surgery for retinal detachment resulting from macular hole in highly myopic eyes. This retrospective analysis was performed on the medical records of highly myopic patients who underwent surgery for retinal detachment [RD] resulting from macular hole at Labbafinejad Hospital, Tehran-Iran from 1992 to 2001. Variables included age, gender number and type of operations, visual acuity before and after the procedures and surgical success rate. Overall, 28 eyes of 27 patients [26 female and one male] with mean age of 59.8 +/- 11 years were included. Main follow-up was 17.3 [range 3-72] months. Mean axial length was 29 +/- 2.74mm [range: 24 to 35mm] and mean degree of myopia was -16.4 +/- 3.1 D [range -10 to -22 D]. Posterior staphyloma was present in 20 eyes [71%]. Seven eyes had undergone failed scleral buckling as the primary procedure prior to referral. lntravitreal SF[6] injection was the primary procedure in 12 eyes with localized detachments; the retina became attached in 5 [41.6%] of these eyes, however redetachment occurred in 7 [584%] eyes. Overall, 23 eyes [including 7 failed scleral buckling cases, 7 redetachments following SF[6] injection and 9 cases of primary surgery] underwent vitrectomy with use of high viscosity silicone oil. No major complications occurred during the operations. Overall, final anatomical success was 92.9% and visual improvement occurred in 85.7% of the eyes. In highly myopic eyes with RD due to macular hole, less invasive procedures such as SF[6] injection seem to be appropriate for eyes with localized detachment. In cases of total or subtotal RD and posterior staphyloma, pars plana vitrectomy and silicone oil tamponade seem to be the preferred procedure

Outcomes of lensectomy in hereditary lens subluxation

To evaluate the results of pars plana lensectomy in patients with hereditary lens subluxation. Hospital records of patients with hereditary lens subluxation who had undergone pars plana lensectomy at Labbafinejad Medical Center, Tehran-Iran from 1996 to 2003 were reviewed. Patients with more than 6 months of follow up were included. Underlying disorders, best corrected visual acuity [BCVA] before and after surgery, intraocular pressure [IOP], postoperative refraction and complications were evaluated. Overall, records of 87 eyes of 49 patients including 27 male and 22 female subjects were reviewed. Mean follow up duration was 20 +/- 18 months. Underlying disorders leading to lens subluxation included Marfan syndrome [79.5%], Weill-Marchesani syndrome [82%], simple ectopia lentis [8.2%], and homocystinuria [4.1%]. The most common indication for surgery was non-correctable refractive error [92.1%]. Mean BCVA was 1.13 LogMAR [20/250] preoperatively, which improved to 0.26 LogMAR [20/30-20/40] postoperatively [P<0.001]. BCVA >/= 20/40 was achieved in 82.8% of cases after surgery. Angle-supported anterior chamber intraocular lens [ACIOL] was implanted in 85.1% of the eyes. Prophylactic band was applied in 63 eyes [72.4%]. Retinal detachment developed in four eyes [4.6%] and was successfully treated. Lensectomy/anterior vitrectomy with implantation of an angle-supported ACIOL in patients with hereditary lens subluxation improves vision significantly without considerable complications

Trans-scleral fixation of posterior chamber intraocular lens combined with vitreoretinal surgery

To report the outcomes of trans-scleral fixation of posterior chamber intraocular lens [PCIOL] combined with complete vitrectomy and prophylactic band placement. Hospital records of 18 patients who underwent the procedure were reviewed. Indications for vitreoretinal surgery included previous penetrating ocular trauma, complicated cataract surgery and vitreous incarceration, and chronic cystoid macular edema. All, patients had iris and angle damage with inadequate lens capsular support. Age, sex, surgical technique, follow up duration and pre- and postoperative best corrected visual acuity [BCVA] were evaluated. Overall 18 eyes of 18 patients [14 men and 4 women] with mean age of 34.8 +/- 23 [range 5-76] years were operated. Mean follow up duration was 36 +/- 32.4 [range 6-96] months. Of the 18 operated eyes 7 were aphakic, 6 had complete IOL dislocation into the vitreous cavity, 4 had subluxated cataractous lens and one had a subluxated IOL. The number of eyes with BCVA >/= 20/40 increased from 3 [16.7%] preoperatively to 9 [50%] postoperatively [P < 0.01]. Postoperative complications were encountered in 9 eyes and included uveitis, vitreous hemorrhage, repeat JUL dislocation and retinal detachment. In the absence of adequate capsular support, trans-scleral fixation of a PCIOL combined with vitreoretinal surgery seems to be effective for visual rehabilitation in selected patients with complicated cataracts or previous cataract surgery. Application of this technique in children deserves caution. Larger studies and a randomized clinical trial with long-term follow up are required to confirm these results

Vitrectomy in chronic uveitis

Vitrectomy was performed on 25 eyes in 21 patients with chronic uveitis from various etiologies. Postoperative follow up averaged 22.8 months with visual improvement in 24 of 25 eyes. In this retrospective study, the techniques employed and the beneficial effect of vitrectomy alone or vitrectomy combined with cataract surgery [lensectomy in most cases] on improving vision and decreasing the number and severity of recurrent attacks of uveitis are reviewed. Also, the indications of surgery, the effect of the surgical procedure on intraocular pressure, the prognostic factors and the management of complications are discussed