Visual acuity with reversed-contrast charts: I. Theoretical and psychophysical investigations.

When the contrast polarity of a visual acuity chart is reversed by using bright letters on a dark background instead of dark on light, the shape and height of the resolution feature in the retinal image is identical but inverted compared with the normal situation. However, the contrast is different in the two cases because the background light level, which is a dividing factor when contrast is calculated, is much less when only the letters are bright. To the extent that contrast is a limiting factor in visual acuity, reversed-contrast acuity would be expected to be better, and proportionally more so in eyes where light scatter and aberrations widen and flatten the point-spread function. In a careful psychophysical study of Landolt C resolution, the minimum angle of resolution was found to be significantly smaller for white letters on a dark background than for the traditional dark on bright situation.     

Topical Metronidazole Gel

Ten putrid-smelling decubitus ulcers were successfully treated with metronidazole gel. Anaerobes were cultured from five ulcers and Wood's light examination was positive in four ulcers before treatment. The odor was eliminated after 36 hours of therapy. All results of post-treatment cultures of anaerobes and Wood's light examinations were negative.     

Der gesunde Patient mit Hypercholesterin?mie

Eine 71-jährige, gesundheitsbewusste, zu einer Medizinerfamilie gehörige Patientin stellt sich zur Bewertung einer seit 10 Jahren bekannten Cholesterinerhöhung und der an anderer Stelle begonnenen Behandlung mit Mevinacor^® (Lovastatin) vor.Im vorausgegangenen Jahr waren bei vielen Gelegenheiten Gesamtcholesterinkonzentrationen zwischen 289 und 345 mg/dl bestimmt worden. LDL wurde bis auf maximal 261 mg/dl erhöht gefunden, die HDL-Cholesterin-Werte lagen zwischen 40 und 48 mg/dl, die Triglyzeride zwischen 99 und 264 mg/dl.