**4.1 Indications and contraindications for intravitreal chemotherapy**

This local therapeutic technique is intended essentially to achieve the highest concentration of the delivered tumoricidal drug into the confined intraocular space adjacent to the tumor. IVitC is used as an adjunctive therapy to chemoreduction with systemic chemotherapy and IAC. The main indications for this treatment modality are the presence of active vitreous seeds that are either refractory to standard therapy or recurrent after pervious standard therapy [7]. The use of IVitC had also expanded lately to include patients with retinal and subretinal tumors where it had been shown to be successful in salvaging the globe of such patients [58].

On the other hands, contraindications preventing the execution of this procedure include tumors involving the ciliary body or extending up to the anterior segment, tumors filling the globe, retinal detachment and vitreous hemorrhage.
