I band

band (band)

1. a part, structure, or appliance that binds; for anatomical structures, see frenulum, tenia, trabecula, and vinculum.

2. in dentistry, a thin metal strip fitted around a tooth or its roots.

3. in histology, a zone of a myofibril of striated muscle.

4. in cytogenetics, a segment of a chromosome stained brighter or darker than the adjacent bands; used in identifying the chromosomes and in determining the exact extent of chromosomal abnormalities. Called Q-b's, G-b's, C-b's, T-b's, etc., according to the staining method used.

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A band  the dark-staining zone of a sarcomere, whose center is traversed by the H band.

band of Broca  a band of nerve fibers that forms the caudal zone of the anterior perforated substance where it adjoins the optic tract.

H band  a pale zone sometimes seen traversing the center of the A band of a striated myofibril.

I band  the band within a striated myofibril, seen as a light region under the light microscope and as a dark region under polarized light.

iliotibial band  see under tract.

M band  the narrow dark band in the center of the H band.

matrix band  a thin piece of metal fitted around a tooth to supply a missing wall of a multisurface cavity to allow adequate condensation of amalgam into the cavity.

oligoclonal bands  discrete bands of immunoglobulins with decreased electrophoretic mobility whose presence in the cerebrospinal fluid may be indicative of multiple sclerosis or other disease of the central nervous system.

Z band  a thin membrane in a myofibril, seen on longitudinal section as a dark line in the center of the I band; the distance between Z bands delimits the sarcomeres of striated muscle.

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I band

n.

A pale band of actin on each side of the Z line of a striated muscle fiber.

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I band

Etymology: ME, band, flat strip

an isotropic band within a striated muscle fiber that appears dark in polarized light but light when stained. See also sarcomere. Compare A band.

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I band

the lighter colored cross-striation of muscle fibers; composed of filaments of actin.

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Patient discussion about I band.

Q. how bad can your headaches get the ones i get feel like a band around my head and my eyes ache.

A. Headache can be very painful; thankfully, headache chronic syndromes can be diagnosed and treated quite effectively. From your description it sounds like you have a well-known headache syndrome (maybe cluster headache). However, effective diagnosis and treatment aren't possible over the net, so I would suggest seeing a doctor in order to treat it.

You may read more here:
http://www.nlm.nih.gov/medlineplus/headache.html