[Comparison of nerve fiber layer thickness between optical coherence tomography and histomorphometry in glaucomatous monkey eyes].

OBJECTIVE To correlate the retinal nerve fiber layer (NFL) thickness measured by optical coherence tomography (OCT) in vivo with histomorphometric measurement. METHODS Four laser-induced glaucomatous eyes of 4 cynomolgus monkeys were studied by OCT scanning a circular area 2.4 mm in diameter around the optic nerve head. The 4 eyes had early or advanced glaucoma. After final OCT measurement, the monkeys were sacrificed and the eyes enucleated. Routine serial section preparations were made, stained with hematoxylin and eosin, and the NFL thickness of 526 sections measured with the aid of a computerized image analysis system was compared with that at the points coincident with the OCT scanned. RESULTS The mean OCT and histomorphometric NFL thickness in glaucoma were (72.2 +/- 54.5) microm and (61.1 +/- 44.2) microm, after the correction of dehydration 15% (70.3 +/- 51.1) microm respectively. Student's t-test showed that the difference was insignificant (t = 1.895, P > 0.05). CONCLUSIONS The NFL thickness measured by OCT in vivo correlates well with that by histomorphometry, and the measurement is accurate.