Comparative Study of a Modified Sub-Tenon’s Capsule Injection of Triamcinolone Acetonide and the Intravenous Infusion of Umbilical Cord Mesenchymal Stem Cells in Retinitis Pigmentosa Combined With Macular Edema

Abstract

Retinitis pigmentosa (RP) is a hereditary retinal degenerative disease leading to eventual blindness. When RP is combined with macular edema (ME), the visual impairment further worsens. We compared a modified sub-Tenon’s capsule injection of triamcinolone acetonide (TA) and the intravenous infusion of umbilical cord mesenchymal stem cells (UCMSCs) in the treatment of RP combined with ME (RP-ME) to assess their safety and efficacy in eliminating ME and restoring visual function. A phase I/II clinical trial enrolled 20 patients was conducted. All patients were followed up for 6 months. There were no severe adverse effects in both groups. In retinal morphological tests, the central macular thickness (CMT) in TA group significantly decreased at first week, first and second month after injection (p < 0.05). The CMT in UCMSCs group significantly decreased at first month after infusion. The rate of reduction of CMT in TA group was significantly greater than that in UCMSCs group at second month (p < 0.05). Reversely, the rate of reduction of CMT in UCMSCs group was significantly greater than that in TA group at sixth month (p < 0.05). In visual functional test, although there were no significant differences in visual acuity or visual fields within each group or between groups, but the amplitude of P2 wave of flash visual evoked potential (FVEP) showed significant increasing in TA group at second month in UCMSCs group at sixth month (p < 0.05). At 6th month, the rate of growth in the amplitude of P2 wave in USMCSs group was significantly greater than that in TA group (p < 0.05). This study suggests both modified sub-Tenon’s capsule injection of TA and intravenous infusion of UCMSCs are safe for RP-ME patients. TA injection is more effective at alleviating ME while improving visual function in a short term. UCMSC intravenous infusion shows slow but persistent action in alleviating ME, and can improve the visual function for a longer time. These approaches can be applied separately or jointly depending on the disease condition for patients to benefit maximumly.Clinical Trial Registration:http://www.chictr.org.cn, identifier ChiCTR-ONC-16008839

Management of Retinitis Pigmentosa Via Wharton’s Jelly-Derived Mesenchymal Stem Cells or Combination With Magnovision: 3-Year Prospective Results

“…The subtenon space is an immunoprotective partially avascular region and is a suitable medium for WJ-MSCs. 55 , 56 There are studies in the literature in which WJ-MSCs are applied more invasively and traumatically as suprachoroidal, subretinal, and intravitreal. Complications such as inflammation, retinal tear, fibrosis, and photoreceptor loss due to surgical trauma have been reported in these invasive applications.…”

“…Complications such as inflammation, retinal tear, fibrosis, and photoreceptor loss due to surgical trauma have been reported in these invasive applications. 56-58 WJ-MSC is effective when administered intravenously, but it was not preferred due to the risk of systemic complications such as thrombosis, embolism and requiring more mesenchymal stem cells. 56 To avoid these complications, we prefer deep subtenon injection that does not enter the globe and can be relatively non-invasive.…”

“… 56-58 WJ-MSC is effective when administered intravenously, but it was not preferred due to the risk of systemic complications such as thrombosis, embolism and requiring more mesenchymal stem cells. 56 To avoid these complications, we prefer deep subtenon injection that does not enter the globe and can be relatively non-invasive. Our goal is to deliver the exosome content to the outer retinal layers.…”