The diagnosis of nonparaneoplastic AIR is usually made based on the presence of antiretinal antibodies and a combination of certain clinical features, in the absence of another specific cause. Recently, criteria and tests for the diagnosis of nonparaneoplastic autoimmune retinopathy including clinical criteria and a standardized assay system for antiretinal antibody detection were suggested by expert panel consensus (Table 15.1) (Fox et al. 2016). The diagnostic criteria include five essential and three supportive criteria. This consensus report mentioned that experts agreed that in order to make the diagnosis of AIR, all essential diagnostic criteria needed to be present. However, the significance of supportive criteria in making the diagnosis was not explored. In this report, consensus was also reached on the six core diagnostic tests to be performed at the initial diagnostic examination (Table 15.1). The core diagnostic tests do not include visual field test or color vision test. Table 15.2 shows basic laboratory survey summary on the detection of antiretinal antibodies for diagnosis of AIR from the expert panel consensus (Fox et al. 2016). Experts agreed that a diagnostic assay system should have a 2-tier design to maximize sensitivity and specificity (i.e. Western blot or immunohistochemistry can be performed initially and subsequently followed by a different diagnostic method among the three methods listed in Table 15.2) (Fox et al. 2016). An example of Western blot in a patient with nonparaneoplastic AIR is shown in Fig. 15.3 (Eo et al. 2015). However, consensus was not reached on the ideal tissue type to use for fixation and detection of serum antiretinal antibodies: three experts selected human tissue and three selected monkey tissue as the ideal tissue type (Fox et al. 2016). This report also mentioned that a simple majority consensus agreed that the number of positive antiretinal antibody subtypes should have more weight toward the diagnosis of AIR (Table 15.2); however, multiple experts stated that more evidence and studies are needed before developing a more complex, weighted assay system (Fox et al. 2016). The MAR and CAR can be diagnosed with similar approaches but with the presence of skin melanoma or other types of cancer, respectively.