In vivo characterization of lamina cribrosa pore morphology in primary open-angle glaucoma.

PURPOSE: To characterize the in vivo morphology of human lamina cribrosa pores in healthy and glaucoma eyes. PATIENTS AND METHODS: In this cross-sectional, observational study, a flood-illumination adaptive optics fundus (FIAO) camera was used to perform in vivo, high-resolution, noninvasive imaging of the optic disc and lamina cribrosa in 30 patients diagnosed with primary open-angle glaucoma (POAG), in 15 healthy controls and in 14 healthy subjects with at least one direct relative with POAG. Two masked graders measured each visible lamina cribrosa pore along the major and minor axes in order to categorize pores as oval (minor/major axis ratio<0.75) or round. We used these same measurements to calculate pore surface area as a best-fit oval. RESULTS: Lamina cribrosa pores were visible in 95.2% of the subjects. In 52% of controls, the pores were visualized under the neuroretinal rim. In POAG patients, 78% of visible pores had an oval shape versus 19.4% in controls (P<0.01). Average pore surface area was significantly different (1561 px(2) versus 724 px(2); P<0.01). In healthy subjects with at least one direct relative with POAG, 21% had pores with an appearance comparable to that of subjects in the glaucoma group. CONCLUSION: On average, lamina cribrosa pores are elongated in POAG eyes and also in healthy eyes of POAG relatives. In vivo characterization of lamina cribrosa pore morphology by FIAO imaging may enhance our understanding of glaucoma, and offer new means for its early detection.

Time-quality tracking of monosodium glutamate, sodium saccharin, and a citric acid-saccharin mixture.

The temporal patterns of taste-quality descriptors evoked by 1000-ms duration stimulus liquids flowed through a closed delivery system over the anterodorsal tongue tip region were indicated using touch-typing on a computer keyboard. Single keys corresponded to the taste words of a 23 item code. A computer monitor displayed for subjects the keys pressed and when they were pressed, starting at stimulus delivery. For 2 mM sodium saccharin (NaSac), 75% of the responses were "sweet," 6.5% "sugar"; for NaSac in 10 mM citric acid (ArtLem), 43% "sour," 20% "citrus," and 11% "sugar"; for 214 mM monosodium glutamate (MSG), 28% "salty," 14% "sour," and 10% 1st "soapy," then "no taste," and finally "bitter." Distilled water received "no taste" on all trials. Response durations were 657 ms for ArtLem, 594 ms for NaSac, 577 ms for MSG. MSG yielded multiple quality responses on 25.5% of the trials; ArtLem, 9%; and NaSac, 1%. These results are compared with temporal patterns for taste intensity and with unrestricted verbal descriptions of the solutions.