**5. Conclusions**

Stem cell therapy is going to change the natural history of various ophthalmologic conditions. For example, several studies have highlighted the chance to repair corneal damage through the implantation of conjunctival cells grown on the amniotic membrane with a good clinical outcome. In addition, an improvement in clinical parameters was observed in patients with limbal stem cell deficiency through the implantation of autologous conjunctival stem cells. This is evidenced by an increase in the visual acuity and a reduction of irritation. Despite biochemical evidences of the existence of stem cell populations in the remaining portions of the anterior segment (trabecular, iris, and crystalline), their clinical use is still under study.

Pioneering studies conducted on animal models have provided hopeful evidence for the hypothesis that stem cell therapy is a valid approach to sight-threatening degenerative retinal diseases, including retinitis pigmentosa, Stargardt's disease, dry age-related macular degeneration, and vascular occlusions. A number of phase I/II clinical trials on humans seem to have confirmed the effectiveness

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**Figure 8.**

*P. Limoli-Milan Low Vision Center.*

**Figure 7.**

*Image courtesy of P. Limoli-Milan Low Vision Center.*

*Another case of dry AMD with saving of the foveal area (above) and T0. Six months after LRRT, despite the progression of the scotoma within the paracentral atrophic areas, the fovea has maintained its sensitivity, and visual performance has been preserved (T180). ERG activity (bottom left) showed an increase (bottom right).* 

*Patient with molecular diagnosis of Stargardt's maculopathy. In 2014, a suprachoroidal graft of autologous mesenchymal cells was performed. Visual performance after 5 years appears unchanged. Image courtesy of* 

*Regenerative Medicine and Eye Diseases DOI: http://dx.doi.org/10.5772/intechopen.92749*

#### **Figure 7.**

*Regenerative Medicine*

surgery. Knowledge of the overall amount of retinal cells is of particular importance: the rehabilitator and surgeon should be aware of this as a precise predictor of

*Patient suffering from dry AMD with a peripheral areolar evolution (blue arrows at the top left). Sensitivity appears to be compromised by a paracentral scotoma, but survival of the fovea allows for good visual ability (bottom left). After autologous suprachoroidal graft of mesenchymal cells (T180), we observed an increase in the thickness of the choroid (top right and center right). Despite the increase in the paracentral scotoma which has become more profound as an expression of a now dying area, the improvement of the choroidal circulation has contributed to the maintenance of the foveal area and the stabilization of visual performance. Image* 

Stem cell therapy is going to change the natural history of various ophthalmologic conditions. For example, several studies have highlighted the chance to repair corneal damage through the implantation of conjunctival cells grown on the amniotic membrane with a good clinical outcome. In addition, an improvement in clinical parameters was observed in patients with limbal stem cell deficiency through the implantation of autologous conjunctival stem cells. This is evidenced by an increase in the visual acuity and a reduction of irritation. Despite biochemical evidences of the existence of stem cell populations in the remaining portions of the anterior segment (trabecular, iris, and crystalline), their clinical use is still under

Pioneering studies conducted on animal models have provided hopeful evidence for the hypothesis that stem cell therapy is a valid approach to sight-threatening degenerative retinal diseases, including retinitis pigmentosa, Stargardt's disease, dry age-related macular degeneration, and vascular occlusions. A number of phase I/II clinical trials on humans seem to have confirmed the effectiveness

outcome for patients treated with cell therapy.

*courtesy of P. Limoli-Milan Low Vision Center.*

**5. Conclusions**

**Figure 6.**

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study.

*Another case of dry AMD with saving of the foveal area (above) and T0. Six months after LRRT, despite the progression of the scotoma within the paracentral atrophic areas, the fovea has maintained its sensitivity, and visual performance has been preserved (T180). ERG activity (bottom left) showed an increase (bottom right). Image courtesy of P. Limoli-Milan Low Vision Center.*

#### **Figure 8.**

*Patient with molecular diagnosis of Stargardt's maculopathy. In 2014, a suprachoroidal graft of autologous mesenchymal cells was performed. Visual performance after 5 years appears unchanged. Image courtesy of P. Limoli-Milan Low Vision Center.*

of this method. We now know for sure that when placed in an appropriate tissue niche stem cells not only survive and proliferate but are capable of differentiating into proper retinal cells which exhibit functional characteristics of real photoreceptors, resulting in the development of a retina-like structure. Further studies are needed to put such promising experimental data into clinical practice and establish standardized procedures for the application of stem cell therapy in the ophthalmological field.
