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Background/Objectives: To evaluate the roles of choroidal blood flow (CBF) and choroidal thickness (CT) as predictors of macular edema recurrence in patients with treatment-naive non-ischemic branch retinal vein occlusion (BRVO) after intravitreal ranibizumab (IVR) injection. Methods: Sixteen eyes from sixteen patients with treatment-naive non-ischemic BRVO treated with IVR, once initially and then as needed, were included in the study. CBF and CT in the subfovea, occlusive, and non-occlusive regions were measured via laser speckle flowgraphy and enhanced depth imaging optical coherence tomography over 12 months. Results: Baseline CT was significantly greater in the occlusive region (335 ± 72.1 µm) than in the non-occlusive region (274 ± 36.7 µm, p = 0.028). CT in the occlusive region was reduced significantly after 1 week (p = 0.008), but CBF did not change significantly after IVR throughout the follow-up period (p > 0.05). The occlusive/non-occlusive region CBF ratio at baseline was significantly associated with the number of IVR injections over 12 months (mean 2.63) in patients with BRVO (p = 0.048). Conclusions: Baseline CBF imbalance in eyes with treatment-naive BRVO may indicate the recurrence of macular edema after ranibizumab therapy. [ABSTRACT FROM AUTHOR]

Joint resistance of Bi-2223/Ag tapes was measured at 77K using a Hall element.

We have achieved a high output power of 6 mW from a 441 nm GaN-based vertical-cavity surface-emitting laser (VCSEL) under continuous wave (CW) operation, by reducing both the internal loss and the reflectivity of the front cavity mirror. A preliminary analysis of the internal loss revealed an enormously high transverse radiation loss in a conventional GaN-based VCSEL without lateral optical confinement (LOC). Introducing an LOC structure enhanced the slope efficiency by a factor of 4.7, with a further improvement to a factor of 6.7 upon reducing the front mirror reflectivity. The result was a slope efficiency of 0.87 W/A and an external differential quantum efficiency of 32% under pulsed operation. A flip-chip-bonded VCSEL also exhibited a high slope efficiency of 0.64 W/A and an external differential quantum efficiency of 23% for the front-side output under CW operation. The reflectivity of the cavity mirror was adjusted by varying the number of AlInN/GaN distributed Bragg reflector pairs from 46 to 42, corresponding to reflectivity values from 99.8% to 99.5%. These results demonstrate that a combination of internal loss reduction and cavity mirror control is a very effective way of obtaining a high output GaN-based VCSEL. [ABSTRACT FROM AUTHOR]