Optic Nerve Meningioma

What is it?

Optic meningioma (also optic nerve meningioma, optic nerve sheath meningioma, and orbital meningioma) is a slow-growing tumor of the optic nerve covering, or meninge. It is a benign neoplasm that can be located in the brain behind the orbit. It normally is identified in adults, most frequently in middle-aged women, and can cause severe, progressive visual loss.

What are the symptoms?

A person with this type of tumor normally has proptosis (the tumor pushes the eye forward so it bulges). When the optic nerve is compressed it can cause optociliary shunt vessels to form, leading to loss of vision. The effects of the tumor depend on the size, location, and degree to which it interferes with the optic nerve and other brain functions. Symptoms can also be double vision and drooping of the eyelid (ptosis).

What is the treatment?

Diagnosis of optic meningioma involves viewing the optic nerve blood vessels, which appears raised if disrupted, and for dilated retinal veins. Ultrasonography is sometimes used to measure the diameter of the optic nerve sheath, and CT imaging of the brain shows the eye is pushed forward by the meningioma and can determine if and how far the meningioma continues into the brain. Treatment involves seeing if and how fast the tumor is spreading. Treatment usually consists of surgery to try to remove the entire meningioma, but sometimes the optic nerve cannot be spared and must also be removed. Therefore, many physicians recommend radiation therapy.

References:

http://www.eyecancer.com/Patient/Condition.aspx?nID=66&Category=Optic+Nerve+Tumors&Condition=Optic+Nerve+Sheath+Meningioma

http://webeye.ophth.uiowa.edu/TONI/FAQ.htm#5

http://webeye.ophth.uiowa.edu/TONI/general.htm

http://www.ispub.com/ostia/index.php?xmlFilePath=journals/ija/vol16n1/meningioma.xml

Rathke's Cleft Cyst

What is it?

A Rathke's cleft cyst (RCC) is a large cyst from a cleft in the pituitary gland that remains as the Rathke's pouch, a normal part of embryological development that forms the pituitary gland, doesn't close during early fetal stages. They are non-cancerous growths that can interfere with normal pituitary actions and are often mistaken as tumors on an MRI. They are most commonly recognized in adults, but are also seen in childhood. These cysts are rare lesions that make up less than 1% of all primary brain masses.

What are some symptoms?

Rathke's cleft cysts are usually occur without symptoms and are incidentally discovered by an autopsy or MRI scan. When symptoms of these cysts do occur, they are usually ones of headaches and visual disturbances. Symptoms that the pituitary is not functioning right include: growth problems, delayed puberty, loss of libido, menstrual irregularities, fatigue, personality changes, and irregular blood pressure. Some other signs are dry skin, consitpation, nausea, and excessive thirst.

How is it treated?

Rathke's cleft cysts are diagnosed usually by MRI imaging and sometimes CT scanning. People with symptomatic cysts primarily opt for surgical removal. The surgeon tries to remove the cyst completely without impairing normal pituitary gland and brain function. One way to remove the cyst is through the nasal sinuses, also called transsphenoidal. If the cyst is located above the pituitary gland, the surgeon will probably have to go in through the skull. Once surgical treatment has been given the likelihood of recurrence is very low, but if the cyst cannot be completely removed physicians sometimes advise radiation treatment.

References:

http://neurosurgery.ucla.edu/body.cfm?id=215

http://www.pituitary.org/disorders/rathkes_cleft_cysts.aspx

http://www.hormone.org/Pituitary/non-secretory.cfm

Otosclerosis

What is it?

Otosclerosis is the abnormal growth of spongy bone in the middle ear that causes structures to not properly work, resulting in conductive hearing loss. Depending on where in the ear the growth is occuring, different kinds of hearing loss can occur. Usually, otosclerosis affects the stapes that is located in the entrance to the inner ear, also called the oval window. The abnormal growth causes the stapes to become attached in the oval window, and sound waves are obstructed from entering the inner ear. Otosclerosis may sometimes impair sensory cells or nerve fibers in the inner ear resulting in sensorineural hearing loss, making the level of hearing loss higher.

What causes it?

Some studies have shown that otosclerosis may be hereditary. A person that has one parent having the disease is 25% more likely to get it, and a person with both parents having the disease is 50% more likely to have it passed on to them. White, middle aged women are more susceptible to it than others. Research proposes that there may be a connection between otosclerosis and pregnancy hormonal changes, and a link between the disease and some viral infections.

What are the symptoms?

The most frequent and obvious sign of otosclerosis is hearing loss. It may start out as an overlooked loss of hearing of low pitched sounds, but it can gradually become worse until it is very severe. Some people may also experience dizziness, issues with balance, or tinnitus.

How is it diagnosed?

People who suffer from the symptoms of otosclerosis will need to see a physician specializing in the ear, an otologist for example, to rule out other illnesses or diseases. the physician may send the patient to an audiologist to diagnose, assess, and rehabilitate impairment of hearing and balance using tests. An audiogram is a graph that shows hearing sensitivity. A tympanogram is a graph that shows the functional ability of the middle ear to carry sound.






How is it treated?

If the hearing loss is mild and the person chooses not to opt to measures such as surgery, a hearing aid may be used to amplify sound. In many cases though, surgery is the first option for the complete treatment of otosclerosis, although some hearing loss can persist post-surgery.
Sometimes a stapedectomy is performed. In this operation, a surgeon removes the old stapes and inserts a prosthetic device that transfer sound waves to the inner ear.

References:

http://www.nidcd.nih.gov/health/hearing/otosclerosis.asp

https://www.audiologyonline.com/articles/article_detail.asp?article_id=288

http://www.radswiki.net/main/index.php?title=Otosclerosis

http://deafness.about.com/cs/etiology/a/otosclerosis.htm

ALS

The reason I chose to research this is once a year usually my work raises money and awareness for research of this disease. So I figured I could learn some information about it.

What is it?

Amyotrophic lateral sclerosis (ALS) is a progressive neurological disease that attacks motor neurons (nerve cells in the lateral brain and spinal cord that reach muscles all over body and are responsible for voluntary movement). The neurons are affected and degenerated until they eventually die. Basically, the brain cannot send messages to muscles in order for them to move. ALS is also referred to as Lou Gehrig's disease, named after a famous baseball player who died of the disease in 1941.

There are an estimated number of 30,000 cases of ALS in the U.S. at any given time. It does not affect some races and ethnicities over others, but it is much more common in males than females. People from the ages of 40 to 60 are most commonly affected, but there have been cases in people much younger than that. Most of the time there are no risk factors that can conclude whether a person will have ALS; it is very random. ALS can be inherited from parents in about 5 to 10 percent of cases. The familial cases usually are a result of one parent carrying the gene encoded for ALS.

Detection of Corticospinal Tract Compromise in Amyotrophic Lateral Sclerosis with Brain MR Imaging: Relevance of the T1-Weighted Spin-Echo Magnetization Transfer Contrast Sequence

What are some symptoms?

Symptoms include weakness of the limbs such as the arms, hands, legs, and feet. Twitching and cramping of the muscles is usually seen. Difficulty speaking (slurred speech) and swallowing can occur. In more advanced stages, difficulty breathing can result and a ventilator is needed to help keep the person alive. Symptoms can progressively get worse, leading to paralysis, and spread to other parts of the body with time.

How is it diagnosed?

There is no one exact test that can verify a person has ALS. A series of tests are given and the diagnosis results as other diseases are ruled out. Exams that the physician usually orders along with reviewing symptoms and signs are:

• EMG (electromyography)- detects electrical activity in muscles using fine wire electrodes

• NCV (nerve conduction velocity)- electrodes send a small shock to muscles to determine function; usually rules out other diseases

• MRI (magnetic resonance imaging)- uses radio waves and a strong magnetic field to visualize brain and spinal cord; used for detection of tumors and other abnormalities

• blood and urine tests
  
• muscle biopsy- removal of piece of muscle if muscle disease is suspected
  
• spinal tap- test the fluid surrounding brain and spinal cord

Detection of Corticospinal Tract Compromise in Amyotrophic Lateral Sclerosis with Brain MR Imaging: Relevance of the T1-Weighted Spin-Echo Magnetization Transfer Contrast Sequence

How is ALS treated?


Today, nothing has been found to reverse or cure ALS. Treatment focuses more on slowing down the stages of ALS and making patients more comfortable as they have to continue to deal with the disease. Physicians can prescribe drugs to reducepain, fatigue, twitching and cramping of muscles, and also for the relief of depression that can sometimes go along with the disease. Physical therapy and speech therapy are offered to help the person try to stay mobile and learn to adapt. Many times, ventilators are needed to inflate and deflate the lungs after advanced stages of ALS have set in and the muscles of the diaphragm are no longer to do so on their own.

There is one FDA approved drug that slows the disease's progression by reducing damage to the motor neurons. Riluzole (Rilutek) reduces the level of glutamate (a chemical messenger in the brain) in the body. The drug does not reverse the stages of ALS, but studies have shown that people who take the drug have longer survival rates by several months. It also prolongs the time before which a person would need to be placed on a ventilator.





References:

http://www.alsa.org/als/what.cfm?CFID=2685063&CFTOKEN=e844aa327d6427ab-87842C7C-188B-2E62-8090905205824399

http://www.ninds.nih.gov/disorders/amyotrophiclateralsclerosis/detail_amyotrophiclateralsclerosis.htm#126484842

http://www.mayoclinic.com/health/amyotrophic-lateral-sclerosis/DS00359/DSECTION=causes