ABSTRACT
BACKGROUND@#Different methods have been used to inject stem cells into the eye for research. We previously explored the intravitreal route. Here, we investigate the efficacy of intravenous and subretinal-transplanted human dental pulp stem cells (DPSCs) in rescuing the photoreceptors of a sodium iodate-induced retinal degeneration model. @*METHODS@#Three groups of Sprague Dawley rats were used: intervention, vehicle group and negative control groups (n = 6 in each). Intravenous injection of 60 mg/kg sodium iodate (day 0) induced retinal degeneration. On day 4 postinjection of sodium iodate, the rats in the intervention group received intravenous DPSC and subretinal DPSC in the right eye; rats in the vehicle group received subretinal Hank’s balance salt solution and intravenous normal saline; while negative control group received nothing. Electroretinogram (ERG) was performed to assess the retinal function at day 0 (baseline), day 4, day 11, day 18, day 26, and day 32. By the end of the study at day 32, the rats were euthanized, and both their enucleated eyes were sent for histology. @*RESULTS@#No significant difference in maximal ERG a-wave (p = 0.107) and b-wave, (p= 0.153) amplitude was seen amongst the experimental groups. However, photopic 30 Hz flicker amplitude of the study eye showed significant differences in the 3 groups (p = 0.032). Within the intervention group, there was an improvement in 30 Hz flicker ERG response of all 6 treated right eyes, which was injected with subretinal DPSC; while the 30 Hz flicker ERG of the nontreated left eyes remained flat. Histology showed improved outer nuclear layer thickness in intervention group; however, findings were not significant compared to the negative and vehicle groups. @*CONCLUSION@#Combination of subretinal and intravenous injection of DPSCs may have potential to rescue cone function from a NaIO3 -induced retinal injury model.
ABSTRACT
BACKGROUND@#Different methods have been used to inject stem cells into the eye for research. We previously explored the intravitreal route. Here, we investigate the efficacy of intravenous and subretinal-transplanted human dental pulp stem cells (DPSCs) in rescuing the photoreceptors of a sodium iodate-induced retinal degeneration model. @*METHODS@#Three groups of Sprague Dawley rats were used: intervention, vehicle group and negative control groups (n = 6 in each). Intravenous injection of 60 mg/kg sodium iodate (day 0) induced retinal degeneration. On day 4 postinjection of sodium iodate, the rats in the intervention group received intravenous DPSC and subretinal DPSC in the right eye; rats in the vehicle group received subretinal Hank’s balance salt solution and intravenous normal saline; while negative control group received nothing. Electroretinogram (ERG) was performed to assess the retinal function at day 0 (baseline), day 4, day 11, day 18, day 26, and day 32. By the end of the study at day 32, the rats were euthanized, and both their enucleated eyes were sent for histology. @*RESULTS@#No significant difference in maximal ERG a-wave (p = 0.107) and b-wave, (p= 0.153) amplitude was seen amongst the experimental groups. However, photopic 30 Hz flicker amplitude of the study eye showed significant differences in the 3 groups (p = 0.032). Within the intervention group, there was an improvement in 30 Hz flicker ERG response of all 6 treated right eyes, which was injected with subretinal DPSC; while the 30 Hz flicker ERG of the nontreated left eyes remained flat. Histology showed improved outer nuclear layer thickness in intervention group; however, findings were not significant compared to the negative and vehicle groups. @*CONCLUSION@#Combination of subretinal and intravenous injection of DPSCs may have potential to rescue cone function from a NaIO3 -induced retinal injury model.
ABSTRACT
@#Steroid-induced glaucoma is the most serious complication of the injudicious use of steroids, particularly among children affected by allergic conjunctivitis. This condition is steroid-dependent, and children are commonly being prescribed topical anti-inflammatories, including topical steroids, by general practitioners. Furthermore, topical steroids are also available over the counter, and this availability contributes to overuse without proper monitoring by an ophthalmologist. We present a series of five cases illustrating the devastating effect of unmonitored, long-term use of steroids among children for vernal keratoconjunctivitis. The medications were prescribed initially by general ophthalmologists and were continually bought over the counter by parents. At the presentation to our center, these patients were already compromised visually, exhibiting glaucomatous optic disc changes and high intraocular pressure. The series highlights the optic nerve damage resulting in irreversible visual compromises among children on long-term, topical steroids and the importance of regular monitoring with a low threshold for ophthalmologist referral.
ABSTRACT
A 28-year-old Malay woman presented with severe loss of vision in both eyes associated with periocular pain on eye movement. She was completely blind at presentation and examination showed optic discs swelling. Optic nerve imaging showed ‘doughnut sign’, characteristic of optic perineuritis. Steroid was given over six months. Visual function improved gradually and was maintained at one year follow-up. This case highlights the importance of differentiation between optic neuritis and optic perineuritis as visual recovery depends on prolonged management with corticosteroid in optic perineuritis.
Subject(s)
Optic NeuritisABSTRACT
A 28-year-old Malay woman presented with severe loss of vision in both eyes associated with periocular pain on eye movement. She was completely blind at presentation and examination showed optic discs swelling. Optic nerve imaging showed ‘doughnut sign’, characteristic of optic perineuritis. Steroid was given over six months. Visual function improved gradually and was maintained at one year follow-up. This case highlights the importance of differentiation between optic neuritis and optic perineuritis as visual recovery depends on prolonged management with corticosteroid in optic perineuritis.