Table 2.

Cost, treatment/limitations for the three most prevalent causes of vision loss

Condition	Cost	Treatment	Limitations
Glaucoma	US: $8157/patient/year (no vision loss) up to $18.670 (with vision impairment) (Feldman et al., 2020); Europe: €969/person/year (Traverso et al. 2005)	Topic beta-blockers (Mantravadi and Vadhar 2015; Foundation 2017)	All treatments target IOP, although it is estimated that half of glaucoma patients do not have an increase in IOP (Shields 2008); Direct medical costs as medication, laser and surgical interventions can not be afforded by a significant part of the population, especially in developing countries (Zhao et al. 2018)
		Cholinergic, alpha-adrenergic, carbonic anhydrase inhibitors (Mantravadi and Vadhar 2015; Foundation 2017)
		Prostaglandin analogs (Mantravadi and Vadhar 2015; Foundation 2017)
		Laser therapy (Garg and Gazzard 2018)
		Surgical procedures (Razeghinejad and Spaeth 2011; Aref et al. 2017)
Diabetic retinopathy	US: $493 million (medical costs in 2004) (Rein et al. 2006) Sweden: €433/patient/year (Heintz et al. 2010); Germany: €671–2933/patient/year (Kähm et al. 2018)	Laser photocoagulation (Stewart 2016)	Target an advanced stage of the disease, uncomfortable administration, high costs, long-term side effects, and ultimately do not cure the disease (Al-Shabrawey et al. 2013; Wong et al. 2016); Clinical studies with pharmacological candidates are still inconclusive or were discontinued due to side effects
		Intravitreal injections of anti-VEGF (Stewart 2016)
		Control of glycemia diet or medication (Stewart 2016)
		Candidates for the treatment of DR: aldose reductase inhibitors, anti-inflammatory drugs, carbonic anhydrase inhibitors, fenofibrate, hyaluronidase, PKCβ1/2 inhibitors, and renin-angiotensin system blockers (Tarr et al. 2012; Ebneter and Zinkernagel 2016)
Age-related macular degeneration	US: $7.133/patient/year (direct medical costs); $30.000/patient/year (additional indirect costs) (Brown et al. 2016)	Intravitreal injection of agents that indirectly block VEGF actions (Amoaku et al. 2015; Khanna et al. 2019);	Anti-VEGF drugs have been less beneficial than expected (Schlottmann et al. 2017); Corticosteroid treatment increases risk for cataract and ocular hypertension (Kuppermann et al. 2015; Rezar-Dreindl et al. 2017)
		Corticosteroid implants as an adjunctive therapy (Campochiaro et al. 2012; Bailey et al. 2017; Vakalis et al. 2015; Bonfiglio et al. 2017)
		Combination of anti-VEGF, corticosteroids and photodynamic therapy with the use of verteporfin (Kawczyk-Krupka et al. 2015)