What's the difference between convex and ophthalmometer?
Convex
Definition:
(a.) Rising or swelling into a spherical or rounded form; regularly protuberant or bulging; -- said of a spherical surface or curved line when viewed from without, in opposition to concave.
(n.) A convex body or surface.
Example Sentences:
(1) Seventy-eight patients presented optochiasmal arachnoiditis: 12 had trigeminal neuralgia; 1, arachnoiditis of the cerebellopontile angle; 6, arachnoiditis of the convex surface of the brain; and 3, the hypertensive hydrocephalic syndrome due to occlusion of the CSF routes.
(2) The intervertebral discs expand centrally and become increasingly convex.
(3) Rocking the hepatocyte-splenocyte cultures changed the elution profile from linear to convex.
(4) Lower density foams can be used only if the impact test standards are rewritten with less emphasis on impacts with convex and pointed objects.
(5) A solution of a specific ligand molecule of constant concentration is introduced into the cell so that its concentration in the cell increases continuously (as in a mixing chamber for forming a convex gradient).
(6) Rotations toward the convexity occur in rotational kyphosis.
(7) The patient's soft-tissue profile was normally convex.
(8) The case of a 49-year-old female with a left parietal convexity meningioma associated with an acute subdural hematoma is described.
(9) This change in shape varied from a slight flattening of the LV and IVS during diastole to total reversal of the normal direction of septal curvature such that the IVS became concave toward the RV and convex toward the LV.
(10) The technique combines the conventional plotting the contour lines and the highlighting, by means of hatching, of the concavities (or convexities) of the 'surface' representative of radioactive distribution.
(11) Ablations of the entire dorsal convexity, and of the mesial and cingulate regions of the cortex, failed to interfere with the spindle bursts and recruiting responses, whereas ablations confined to the orbital cortex alone abolished completely these potentials in the cortex and thalamus.
(12) The method uses overlapping of Pi1, 3 and 4 in perfect centering of the lens in the axis of the eye (it is assessed by drawing a perpendicular line on the centre of the cornea) and marked dislocation of Pi3 in the direction of decentration of the planoconvex lens with the convexity facing the cornea.
(13) In the trunk, e.g., in the buttock and the breast, it is useful to reconstruct the natural convexity.
(14) Rats with spinal deformity showed an imbalance of the paraspinal muscles when assessed by EMG; this was expressed by an increase of muscular activity on the convex side.
(15) The diagnostic criteria of median nerve compression (carpal tunnel syndrome) include morphological and signal changes in the nerve, abnormal palmar convexity of the flexor retinaculum and signs of tenosynovitis of the intracarpal flexor tendons.
(16) Microvillus formation was not observed when cell volume was increased by incubation of tissue in half-normal amphibian Ringer's solution for 30 min, or with exposure to acetylcholine, which caused accentuation of the convexity of the apical surface of the granular cell similar to that observed with VP-induced osmotic water flow.
(17) Meningiomas of the convexities (six patients) turned out to be particularly susceptible to complete embolizations.
(18) The granulomatous lesions were classified by location into basilar, convexity, intrahemispheric, and periventricular white-matter involvement.
(19) One exception to this is observed in the brain, where arteries come in from the base and veins collect over the convexity.
(20) The shapes of false lumina assessed by enhanced CT scans at the time of discharge were categorized in three types; 21 patients (group A) without false lumina of the aorta, or with a small crescentic false lumen in the thoracic aorta (type a), six patients (group B) with intimal flaps and two contrast-material-filled lumina in the thoracic aorta (type b), and nine patients (group C) with expanded false lumina or a false lumen whose margin was convex towards a true lumen in the thoracic aorta (type c).
Ophthalmometer
Definition:
(n.) An instrument devised by Helmholtz for measuring the size of a reflected image on the convex surface of the cornea and lens of the eye, by which their curvature can be ascertained.
Example Sentences:
(1) Keratometry with the Javal ophthalmometer showed a mean cornea radius of 8.77 mm.
(2) In order to determine the power of intraocular lenses more easily prior to cataract surgery, we compared the results obtained by automatic measurement of the corneal refractive power by the Humphrey Autokeratometer with manually obtained measurements using the Zeiss ophthalmometer.
(3) The refraction of the unilateral aphakic patient has been aided by recent improvements in the ophthalmometer.
(4) We examined 92 normal eyes using Javal Ophthalmometer and Corneal Analysis System (EyeSys) intending to compare the keratometric readings obtained by these two instruments.
(5) The standard was fixated on a face support of ophthalmometers (of the firms "Rodenstock" and "Karl Zeiss") by means of a support providing transference of the standard in two reciprocally perpendicular meridians on the given (5-35) number of grades.
(6) To interpret scale readings below 30 dioptres and over 60 dioptres we compiled an extension table, suited to the ophthalmometer of Javal-Schiøtz (Haag-Streit), making use of low-powered minus and plus auxiliary lenses in front of the tube of the instrument.