[Significance of the lactate dehydrogenase level in aqueous humor in the diagnosis of retinoblastoma].

Aqueous humor LDH levels of 104 patients (113 eyes) were determined. In 18 patients (18 eyes) with retinoblastoma, the range was 3,850.8-86,717.3 mumol.s-1/L, very significantly higher than those of cataract, glaucoma, retinal detachment, and penetrating eye injury (P less than 0.01). The LDH values of 7 eyes of chronic endophthalmitis were 1,917.1-84,250.2 mumol.s-1/L and that of 1 eye with choroidal malignant melanoma was 19,553.9 mumol.s-1/L, the differences being insignificant (P greater than 0.05). The authors deemed that aqueous LDH levels exceeding 16,670 mumol.s-1/L could be indicative of retinoblastoma; however, with a pseudo-positive rate of 28.6% and a pseudo-negative rate of 16.7%, its practical use in differential diagnosis was limited.