## 4 Discussion and Conclusions  
Blue light (400-480 nm) has been shown to affect flavin and cytochrome constituents associated with mitochondria, and to decrease the rate of ATP formation, with a related production of ROS and cell death [25]. On the contrary, red light (650-800 nm) has been shown to affect mitochondrial complex IV or cytochrome oxidase, and to increase the rate of formation of ATP, with a related generation of a number of beneficial factors [25].  
The thermodynamic approach highlights that external stimuli can induce continuous metabolic generation, characterised by a relation between the ion fluxes and heat power density generated. Indeed, it has been shown a relation between photobiomodulation and nerve regeneration, with a related increase in the number of myelinated fibres and an improvement of electrophysiological function, leading to the conclusion that beneficial effects occur in relation to the recovery of nerve lesions [16].  
So, a possible approach could be related to visible light stimulation. In order to generate the appropriate stimuli, we referred to the results obtained in the analysis of optimal  
Figure 2: Example of the effect of the experimental light stimulation, as designed by the thermophysical approach. The patient is a 54-year-old man with glaucoma since he was 45, without any other pathology. The patient has been treated for 5 months, ten minutes per day everyday during any month, for each eye. The optical tomography of a patient before the treatment (**A**) and after the treatment (**B**). It is possible to highlight an improvement in the Nerve Fibre Layer. OS means Left Eye. OD means Right Eye. The colour scheme in the OCT is defined as follows: green colour code represents normality, yellow represents the suffering state and red represents the damaged state. The OCT system used has been the Zeiss CIRRUS 5000.  
vision perception [54, 57], which lead to the frequencies summarised in Table 2. Indeed, they appear the frequencies related to the spontaneous optimisation of the biological processes for vision, as discussed in Ref. [58]. These experimental results follow the same approach as our theoretical one, which is based on optimisation theory in engineering thermodynamics [43, 59]. In this paper, we summarise the results obtained by a first experimental proof in order to point out the effect of the visible light, if used in subsequent monochromatic stimulations.  
The results obtained open the way to future trials in order to design a therapeutical device for the glaucoma treatment to be considered in addition to the pharmacological treatments, in order to improve the quality of life of the patients.  
This paper is a communication, so it represents a starting point for future deeper analyses of the present experimental evidence, which represent preliminary results that must be improved on considering a larger set of patients. So, we think that, after an improvement of this evidence by a more detailed experimental analysis which will be developed in the next future six months, and the results will be statistically significant and will point out improvement in clinical examinations, then this approach could be considered for possible use in the clinical treatments for glaucomatous patients, in order to support the drug therapies for an improvement of the vision restoration of the patients, and a consequent their well-being.