PubMed HealthSearch

PubMed · 2237065

[Sudden blindness].

Abstract

Blindness means no light perception. In that case one observes a fixed dilated pupil. An unilateral amaurosis of sudden onset is caused either by an ocular or an optic nerve condition. The most common causes are: --occlusion of the central retinal artery --apoplexy of the papilla --traumatic lesions to the optic nerve Bilateral blindness occurring suddenly is for anatomic reasons due to a chiasmatic lesion. It is mainly associated with pituitary apoplexy. More commonly bilateral blindness develops sequentially and may be discovered only after the second event. Besides other ocular diseases bilateral occipital brain infarction has to be considered.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

P Bischoff. 1990-10-23. [Sudden blindness].. https://pubmed.ncbi.nlm.nih.gov/2237065/

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

Acute spermatic cord torsion alters the microcirculation of the contralateral testis.

PURPOSE: The purpose of this study was to characterize the hemodynamic changes in the contralateral testis during acute spermatic cord torsion in anesthetized rats. MATERIALS AND METHODS: We used videomicroscopy to examine the microcirculation of the contralateral testis following acute torsion. Specifically, we examined the effect on vasomotion, a rhythmic dilation and constriction of the arterioles that is involved in fluid and nutrient exchange and modulation of local vascular resistance. In a separate set of experiments, blood flow in the contralateral internal spermatic artery was measured with an ultrasonic flow probe during acute torsion. RESULTS: Following 720 degrees torsion, the amplitude of vasomotion in the contralateral testis increased 121% (29.0 +/- 3.9% versus 13.0 +/- 1.7%) compared with controls. Blood flow in the contralateral internal spermatic artery decreased 43% after 2 hours' torsion. CONCLUSIONS: Acute spermatic cord torsion altered the microcirculation by increasing the amplitude of vasomotion and decreased total blood flow to the opposite testis. Because the hydraulic resistance of a blood vessel exhibiting vasomotion is always less than a vessel with the same average but static diameter, the observed microcirculatory changes may be an adaptive response to preserve local flow in the presence of decreased total flow. The long-term consequences of these changes in the microcirculation may affect testicular function and ultimately fertility.

Acute Disease