RESUMO
PURPOSE/METHODS: We evaluated visual field testing, using indirect ophthalmoscopy, in patients with retinal detachment or retinoschisis. While performing ophthalmoscopy, we projected a shadow onto the schisis or detachment by holding a scleral depressor on the observer's side of the condensing lens. A response was recorded as positive if the patient saw the shadow. RESULTS/CONCLUSION: In all 20 detachment eyes, compared to zero of 12 schisis eyes, the response was positive. Indirect ophthalmoscope perimetry can help distinguish retinoschisis from retinal detachment.
Assuntos
Oftalmoscopia/métodos , Degeneração Retiniana/diagnóstico , Descolamento Retiniano/diagnóstico , Testes de Campo Visual/instrumentação , Humanos , Retina/patologia , Retina/fisiopatologia , Degeneração Retiniana/fisiopatologia , Descolamento Retiniano/fisiopatologia , Campos Visuais/fisiologiaRESUMO
The question of whether A-bands shorten during contraction was investigated using two methods: high-resolution polarization microscopy and electron microscopy. During shortening from extended sarcomere lengths in the passive state, sarcomere-length changes were essentially accounted for by I-band shortening. During active shortening under otherwise identical conditions, the sarcomere length change was taken up approximately equally by A- and I-bands. Several potential artifacts that could give rise to apparent A-band shortening were considered and judged unlikely. Results obtained with polarization microscopy were similar to those obtained with electron microscopy. Thus, modest but significant thick filament shortening appears to occur during active sarcomere shortening under physiological conditions.
