1. A method for detecting and monitoring an optic neuropathy of a retina, comprising: determining for at least a portion of the retina, a set of ratio values (R) between a total backscattered signal intensity from one or more target layers of the retina and a total backscattered signal intensity from one or more reference layers of the retina; and determining for at least the portion of the retina, a set of integrated attenuation values (μ ATT d) related to the set of ratio values, wherein each ratio value is used as a proxy measurement for determining a corresponding integrated attenuation value, wherein μ ATT ⁢ d = log ⁡ ( R ⁢ / ⁢ β + 1 ) 2 , where β is modeled as a substantially constant value, R is the ratio value, and μ ATT d represents a total attenuation of light over a depth d of the retina.