| convergence nucleus of Perlia | A small cell group located between the somatic cell columns of the oculomotor nuclei. Since it is placed between the groups of motor neurons innervating, respectively, the left and right medial rectus muscles, the nucleus is considered to possibly represent an integrating mechanism for ocular convergence. Synonym: convergence nucleus of Perlia, Spitzka's nucleus. (05 Mar 2000) |
|---|---|
| convergence, ocular | The turning inward of the lines of sight toward each other. (12 Dec 1998) |
| convergence-retraction nystagmus | Irregular, jerky nystagmus combining convergence and retraction of the eye into the orbit, especially on attempting an upward gaze. Synonym: Koerber-Salus-Elschnig syndrome. (05 Mar 2000) |
| points of convergence | <microscopy> In colour video cameras and monitors, the precise alignment of the images or pictures in the three primary colours (red, green and blue). A lack of convergence gives rise to asymmetrically coloured fringes. (05 Aug 1998) |
| positive convergence | Inward deviation of the visual axes even when convergence is at rest, as in cases of convergent squint. (05 Mar 2000) |
| near point of convergence | The point to which the visual lines are directed when convergence is at its maximum. (05 Mar 2000) |
| negative convergence | The slight divergence of the visual axes when convergence is at rest, as when observing the far point or during sleep. (05 Mar 2000) |
| far point of convergence | The point to which the visual lines are directed when convergence is at rest. (05 Mar 2000) |
| unit of convergence | See: meter angle. (05 Mar 2000) |
| unit of ocular convergence | The amount of convergence required to view binocularly an object 1 meter distant and exerting 1 diopter of accommodation. Synonym: unit of ocular convergence. (05 Mar 2000) |
| acute adrenocortical insufficiency | Severe adrenocortical insufficiency when an intercurrent illness or trauma causes an increased demand for adrenocortical hormones in a patient with adrenal insufficiency due to disease or use of relatively large amounts of similar hormones as therapy; characterised by nausea, vomiting, hypotension, and frequently hyperthemia, hyponatraemia, hyperkalaemia, and hypoglycaemia; can be fatal if untreated. Synonym: addisonian crisis, adrenal crisis, Bernard-Sergent syndrome. (05 Mar 2000) |
| adrenal gland insufficiency | <endocrinology> A condition that results from the inadequate production of adrenal hormones (see Addison's disease). (27 Sep 1997) |
| adrenal insufficiency | <endocrinology> A condition that results from the inadequate production of adrenal hormones (see Addison's disease). (27 Sep 1997) |
| adrenocortical insufficiency | Loss, to varying degrees, of adrenocortical function. Synonym: hypocorticoidism. (05 Mar 2000) |
| aortic insufficiency | A congenital or acquired heart valve abnormality that results in the abnormal back flow of blood in the aorta, through an incompetent aortic valve and into the left ventricle. Chronic aortic insufficiency leads to enlargement of the left ventricle and pulmonary congestion. If left uncorrected, congestive heart failure will result. Aortic valve replacement is eventually necessary in most cases of significant valvular incompetence. (27 Sep 1997) |