Limbal nodule
Encyclopedia
A limbal nodule is a non-specific term describing any nodular lesion at the limbus
(junction of the cornea
and sclera
) of the eye
.
The differential diagnosis
for a limbal nodule can include:
Corneal limbus
The corneal limbus is the border of the cornea and the sclera . The limbus is a common site for the occurrence of corneal epithelial neoplasm....
(junction of the cornea
Cornea
The cornea is the transparent front part of the eye that covers the iris, pupil, and anterior chamber. Together with the lens, the cornea refracts light, with the cornea accounting for approximately two-thirds of the eye's total optical power. In humans, the refractive power of the cornea is...
and sclera
Sclera
The sclera , also known as the white or white of the eye, is the opaque , fibrous, protective, outer layer of the eye containing collagen and elastic fiber. In the development of the embryo, the sclera is derived from the neural crest...
) of the eye
Human eye
The human eye is an organ which reacts to light for several purposes. As a conscious sense organ, the eye allows vision. Rod and cone cells in the retina allow conscious light perception and vision including color differentiation and the perception of depth...
.
The differential diagnosis
Differential diagnosis
A differential diagnosis is a systematic diagnostic method used to identify the presence of an entity where multiple alternatives are possible , and may also refer to any of the included candidate alternatives A differential diagnosis (sometimes abbreviated DDx, ddx, DD, D/Dx, or ΔΔ) is a...
for a limbal nodule can include:
- PingueculaPingueculaA pinguecula is a common type of conjunctival degeneration in the eye.-Presentation:It is seen as a yellow- white deposit on the conjunctiva adjacent to the limbus . It is to be distinguished clinically from pterygium, which is a wedge shaped area of fibrosis that appears to grow into the cornea....
- Early PterygiumPterygiumPterygium most often refers to a benign growth of the conjunctiva. A pterygium commonly grows from the nasal side of the sclera. It is usually present in the palpebral fissure. It is associated with, and thought to be caused by ultraviolet-light exposure , low humidity, and dust...
- Foreign bodyForeign bodyA foreign body is any object originating outside the body. In machinery, it can mean any unwanted intruding object.Most references to foreign bodies involve propulsion through natural orifices into hollow organs....
/ foreign body granuloma - Phlycten, an inflamed nodule of lymphoid tissue
- Episcleritis
- ScleritisScleritisScleritis is a serious inflammatory disease that affects the white outer coating of the eye, known as the sclera. The disease is often contracted through association with other diseases of the body, such as Wegener's granulomatosis or rheumatoid arthritis; it can also be attained through disorders...
- GranulomaGranulomaGranuloma is a medical term for a tiny collection of immune cells known as macrophages. Granulomas form when the immune system attempts to wall off substances that it perceives as foreign but is unable to eliminate. Such substances include infectious organisms such as bacteria and fungi as well as...
- Limbal dermoid, a kind of choristoma (NB: in other organs dermoid can refer to a teratomaTeratomaA teratoma is an encapsulated tumor with tissue or organ components resembling normal derivatives of all three germ layers. There are rare occasions when not all three germ layers are identifiable...
) - malignant melanoma