collarette

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collarette

 [kol″er-et´]
1. a narrow rim of loosened keratin overhanging the periphery of a circumscribed skin lesion, attached to the normal surrounding skin.
2. an irregular jagged line dividing the anterior surface of the iris into two regions, the pupillary zone and the ciliary zone.
From Dorland's, 2000.
Biett's collarette a type of papular syphilid in which the central papule is surrounded by a ring of scales.

col·lar·ette

(kol'er-et'),
1. The sinuous, scalloped line in the iris that divides the central pupillary zone from the peripheral ciliary zone and marks the embryonic site of the atrophied minor vascular circle of the iris.
2. Brittle scales encircling eyelashes in staphylococcal blepharitis.
Synonym(s): iris frill

collarette

/col·lar·ette/ (kol″er-et´)
1. a narrow rim of loosened keratin overhanging the periphery of a circumscribed skin lesion, attached to the normal surrounding skin.
2. an irregular jagged line dividing the anterior surface of the iris into two regions.
Dermatology A rim of thickened epidermis in pyogenic granuloma, which is morphologically similar to the pincer-like surrounding epidermis of lichen nitidus and keratoacanthoma
Mycology A rim of cell wall material at the tip of a phialide, resulting from the tip’s rupture during the release of the first phialoconidium

collarette 

Line separating the pupillary zone and the ciliary zone which can be seen on the anterior surface of the iris. In the normal iris it is an irregular circular line lying about 1.5 mm from the pupillary margin (Fig. C13). See minor arterial circle of the iris; crypts of Fuchs.
Fig. C13 Coloboma of the irisenlarge picture
Fig. C13 Coloboma of the iris

collarette

a small collar; see epidermal collarette, iris collarette.