Figure 10. Saturation-Value Scale for Quantifying Leukocoria in Photographs of Children with Retinoblastoma.

A) Sectioning the Saturation-Value plane of HSV color space into a useful scale for classifying pupillary reflexes in recreational photographs. In this proposed scale, leukocoria is divided into differing degrees of brightness and color concentration (1° being the brightest, least colored; 3° is the least bright and most colored); areas that likely represent a typical “red” or “black” pupillary reflex are indicated. Each data point labeled “Rb” refers to the average H, S, or V of all leukocoric images of one of nine patients; the superscript of each label refers to the patient number (beginning with zero); subscript text refers to right or left pupil. “PL” refers to Pseudo-Leukocoria from images of a healthy individual that were collected with one of three different camera phones; the subscript refers to the camera that was used to photograph the individual (see text). “NL” refers to Non-Leukocoric controls (average of right and left pupils) from healthy children (i.e., data contained in Figure 5 and Table 1). The value “n” below each Rb, NL, and PL point refers to the number of pictures from which each average was calculated. B) Plot showing the average Hue of cropped pupils from panel A.