Topical administration of prostaglandin F2a (PGF2a) produced a reduction in intraocular pressure in eyes of rabbits, cats, and cynomolgus monkeys. In rabbit eyes at 5 or 6 hr, 50 ng, 100 ng, or 250 ng of PGF2a caused a significant intraocular pressure reduction with a small miotic effect. Treatment with 500 ng, 750 fig, or 1000 ng of PGF2a lowered intraocular pressure significantly in cat eyes ...

PURPOSE To measure and quantify effects of variation in retinal illuminance on frequency doubling technology (FDT) perimetry. METHODS A Zeiss-Humphrey/Welch Allyn FDT perimeter was used with the threshold N-30 strategy. Study 1, quantifying adaptation: 11 eyes of 11 subjects (24-46 years old) were tested with natural pupils, and then retested after stable pupillary dilation with neutral densi...

BACKGROUND The pupillary light reflex characterizes the direct and consensual response of the eye to the perceived brightness of a stimulus. It has been used as indicator of both neurological and optic nerve pathologies. As with other eye reflexes, this reflex constitutes an almost instantaneous movement and is linked to activation of the same midbrain area. The latency of the pupillary light r...

We used filtered low spatial frequency images of facial emotional expressions (angry, fearful, happy, sad, or neutral faces) that were blended with a high-frequency image of the same face but with a neutral facial expression, so as to obtain a "hybrid" face image that "masked" the subjective perception of its emotional expression. Participants were categorized in three groups of participants: h...

PURPOSE To evaluate the influence of the size of the light exposed pupil in one eye on the pupillary light reflex of the other eye. METHOD Using a monochromatic pupillometer, the left eye in each of 10 healthy subjects was exposed to 20 s of monochromatic light of luminance 300 cd/m(2), first red (660 nm) and in a following session, blue (470 nm) light. The consensual pupillary diameter in th...

PURPOSE To evaluate B-mode ultrasound as a novel method for the examination of pupillary function and to provide normal values for the pupillary reflex as assessed by B-mode ultrasound. METHODS 100 subjects (49 female, 51 male, mean [range] age 51 [18-80 years]) with no history of ophthalmologic disease, no clinically detectable pupillary defects, and corrected visual acuity ≥ 0.8 were includ...

• The baroceptors of the carotid sinus (and arterj') and the aortic arch are the major sense organs which reflexly control the systemic blood pressure. Since the demonstration of the reflex function of these receptors, there has been much work on the responses of the blood pressure, heart, and peripheral vessels to changes in pressure in the carotid arteries and the aorta," on blood flow in par...

Background. Spontaneous orbital haemorrhage is a very rare condition and vision-threatening event. It may occur due to trauma, orbital surgery/injections, orbital vascular anomalies, and a variety of systemic predisposing factors. Signs of retrobulbar hemorrhage include proptosis, ophthalmoplegia, increased intraocular pressure, loss of pupillary reflexes, and optic disc or retinal pallor. Both...