pin-head pigmentation spot
| sacral vertebrae | The segments of the vertebral column, usually five in number, that fuse to form the sacrum. Synonym: vertebrae sacrales. (05 Mar 2000) |
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| intermediate sacral crests | Crests formed by the fusion of articular processes of all the sacral vertebrae. Synonym: articular crests, cristae sacrales intermediae. (05 Mar 2000) |
| lateral sacral artery | <anatomy, artery> Usually one of two arteries which arise from the internal iliac artery or its branches; they supply muscles and skin in the neighborhood and send branches into the sacral canal, supplying radicular and spinal arteries, and continuing on to the skin and subcutaneous tissues overlying the sacrum. Synonym: arteria sacralis lateralis. (05 Mar 2000) |
| lateral sacral crests | Crests which are rough ridges lying lateral to the sacral foramina; they represent the fused transverse processes of sacral vertebrae. Synonym: cristae sacrales laterales. (05 Mar 2000) |
| lateral sacral veins | Several veins that receive the drainage of the sacral venous plexus and sacral intervertebral veins then accompany the corresponding artery and empty into the internal iliac vein on each side. Synonym: venae sacrales laterales. (05 Mar 2000) |
| age spot | <dermatology> A skin disorder seen with aging (or sun exposure) where there are flat patches of increased pigmentation on the skin. They are nonserious, benign and generally more important cosmetically. The most commonly appear on sun exposed areas such as the forehead and the back of the hands. Avoidance of the sun and the use of a sunscreen (SPF of 15) can reduce the incidence of these lesions. Creams and lotions are available which bleach the skin. Cryotherapy can be used in some cases. (27 Sep 1997) |
| blind spot | The negative scotoma in the visual field, corresponding to the optic disk. Synonym: blind spot. (05 Mar 2000) |
| blue spot | A bluish stain on the skin caused by the bites of fleas or lice, especially pediculosis pubis. Synonym: blue spot, tache bleuatre. (05 Mar 2000) |
| cafe-au-lait spot | <dermatology> A pigmented cutaneous lesion, that can range from light to dark brown, and is due to an excess of melanosomes in the malpighian cells, rather than to an excess of melanocytes. Caf |
| Mariotte's blind spot | The portion of the optic nerve seen in the fundus with the ophthalmoscope. It is formed by the meeting of all the retinal ganglion cell axons as they enter the optic nerve. Because the retina at the optic disk has no photoreceptors there is a corresponding blind spot in the visual field. (12 Dec 1998) |
| cherry-red spot | The ophthalmoscopic appearance of the normal choroid beneath the fovea centralis, appearing as a red spot surrounded by white retinal oedema in central artery closure or lipid infiltration in sphingolipidosis. Synonym: Tay's cherry-red spot. (05 Mar 2000) |
| cherry-red spot myoclonus syndrome | <syndrome> A neuronal storage disorder in children characterised by a cherry red spot at the macula, progressive myoclonus, and easily controlled seizures; the result of sialidase deficiency. Type 1 is characterised by normal body habitus, cherry red macula, myoclonus, and normal beta-galactosidase levels; type 2 by short stature, bony abnormalities, and deficient beta-galactosidase. Synonym: sialidosis. (05 Mar 2000) |
| mongolian spot | <dermatology> A benign bluish or bruised-appearing birthmark that is usually located on the lower back or buttocks. More common in dark-skinned races and may persist for months to years. (27 Sep 1997) |
| white spot | Gray-white or white, rounded or irregularly shaped, slightly opaque patches or spots that are sometimes observed postmortem in the epicardium, especially in middle-aged or older persons; they result from fibrous thickening, and sometimes hyalinization, of the epicardium; similar lesions may also occur in the visceral layer of the peritoneum. Synonym: macula lactea, macula tendinea, tache blanche, tache laiteuse, tendinous spot, white spot. (05 Mar 2000) |
| white spot disease | Small discrete, white, waxy, indurated lesions due to localised degenerative changes in the fibrous tissue. Synonym: white spot disease. (05 Mar 2000) |