The optic nerve carries electrical impulses from your eye to your brain. Damage to the optic nerve can affect your ability to sight. Several types of calcium deposits can develop in the optic nerve. Calcium deposits may develop within protein deposits in the optic nerve known as drusen. High calcium levels do not cause or contribute to optic nerve drusen, which may run in families. High calcium levels in the blood can cause metastatic calcification in the optic nerve. Trauma to the optic nerve and tissue death can also cause optic nerve calcification.
Optic Nerve Drusen
Optic nerve drusen affect around 1 percent of the United States population, occurring mostly in Caucasians and affecting both eye in 80 percent of cases, according to Massachusetts ophthalmologist Dwayne B. Baharozian, M.D., of the Family Eye Care Center. Optic nerve drusen affect males and females equally. Optic nerve drusen aren't present at birth; they normally become visible during the teen years. Calcium deposits make the drusen easier to see, making diagnosis more obvious. Some peripheral vision loss occurs in 70 percent of people with optic nerve drusen, according to the North American Neuro-Ophthalmology society, although you may not notice the loss.
Metastatic calcification of the optic nerve can occur if you have high levels of calcium in your bloodstream, medically known as hypercalcemia. Cancers in other part of the body can spread to the optic nerve, causing calcium deposits to form. The University of California-Los Angeles Optic Neuropathy Center reported such a case in the March 1995 issue of "Archives of Ophthalmology." A 71 year old woman developed metastatic spread of a lung tumor to the brain and then to the optic nerve. Other causes of metastatic calcification not necessarily related to cancer include elevated elevated parathyroid hormone levels, bone destruction, vitamin D abnormalities and kidney failure.
Trauma to the eye that leads to tissue damage can cause optic nerve calcifications. The mitochondria inside damaged cells accumulate calcium. Calcification can also occur outside the cells after trauma when calcium ions bind to phospholipids in membrane-bound vesicles. Australian researchers published an article in the December 2004 "Journal of Neuro-Ophthalmology" describing two cases of trauma that resulted in optic nerve calcification and severe vision loss in one case.
Dietary calcium intake neither causes nor improves calcium despots in the optic nerve in any way. High calcium levels in the blood do not occur from eating foods high in calcium, although taking high doses of calcium and vitamin D could cause hypercalcemia. Follow up with your ophthalmologist regularly if you have calcium deposits on your optic nerve.
- The Family Eye Care Center; Optic Nerve Drusen; Dwayne B. Baharozian, M.D.
- West Metro Ophthalmology: Optic Nerve Drusen
- North American Neuro-Ophthalmology Society: Optic Nerve Drusen
- "British Journal of Ophthalmology"; Idiopathic Dural Optic Nerve Sheath Calcification; B. Nicholson, et al.; June 2009
- "Journal of Neuro-OphthOptic Nerve Calcification After Trauma; John Crompton, et al.; December 2004
- "Archives of Ophthalmology"; Metastasis of Adenocarcinoma of the Lung to optic Nerve Sheath Meningioma; A. Arnold, et al.; March 1995