The ultrasonic appearance of retinoschisis is a single echo similar to, but of smaller amplitude than that of retinal detachment and separated from the scleral echo by a silent space representing subretinal fluid . Quantitative ultrasonic measurements were made in a series of patients and show a statistically significant difference between the acoustic reflectivities of the separated retina in retinoschisis and retinal detachment.
Cavernous hemangiomas of the orbit produce echographic A-scan patterns which allow their detection, localization, measurement, and differentiation from all other orbital lesions with a high degree of accuracy. Specific echograms, however, of these tumors can only be obtained with optimized and standardized A-scan instruments providing specific settings of the sensitivity, amplifier characteristics, dynamic range, expansion of the screen display, filtering, etc. When instruments other than these are used, both differentiation and detection of this tumor become difficult or impossible. The more an A-scan instrument differs from the optimized and standardized type, the less successful the diagnosis of cavernous hemangiomas becomes, B-scan techniques add to the A-scan examination by better demonstrating the round shape and the topographic relationship to the globe, the optic nerve and the orbital wall.
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