BROWN SYNDROME

HISTORY

Brown syndrome was first discovered by Harold Brown in 1950 when he studied patients with an unusual motility disorder in the eye. It was characterized by;
divergence in straight upgaze (V pattern)
limited elevation in adduction
normal elevation in abduction
Compensatory chin elevation for binocular fusion.
He attributed this disorder to a short or tight anterior superior oblique tendon sheath. In Brown’s classic study of 126 patients, there was a higher incidence of the syndrome in females (59%) than males (41%). The right eye involvement was 55%, the left eye 35%, and bilateral 10%.

CONGENITAL AND ACQUIRED CAUSES
Brown syndrome can be divided into two types congenital and acquired.

Congenital Brown Syndrome is a developmental abnormality that limits the eye at birth. A few theorical causes are;
1. A short and stiff superior oblique tendon complex that restricts ocular elevation
2. A form of congenital fibrosis of the superior oblique muscle
3. Tendon-slackening that comes from a telescoping elongation of the central tendon
4. A developed abnormality of the elastic-crossed fibers that normally allow the telescoping movement of the central tendon fibers

Acquired Brown Syndrome is an abnormal condition that is acquired in late childhood or adulthood of the eye. Some theorical causes are;
1. A rare acquired fibrosis of the superior oblique muscle
2. A superior oblique tendon tuck
3. A mass that displaces the tendon or a scleral buckling
4. Abnormal telescoping mechanism which can be constant or intermittent
5. Extensive scarring around the trochlea from trama or surgery which can restrict the tendon movement in both ways

TREATMENT

The treatments for Brown Syndrome are anti-inflammatory medication such as oral ibuprofen, oral corticosteroids and steroid injections in the area of the trochlea. Spontaneously resolution rarely occurs except in non-traumatic acquired cases. Congenital cases are unlikely to improve spontaneously; therefore, surgery should be considered.
The presence of chin elevation and severe limitation of elevation in adduction is the most important indication for surgery. MRI exams of the orbit may identify pathology for acquired Brown Syndrome; especially if pain, discomfort, signs of inflammation or an atypical pattern of strabismus is present.

For more information go to: http://www.emedicine.com/oph/topic552.htm

Prolactinoma

Causes of PROLACTINOMA

Prolactinoma is the most common benign tumor (adenoma) of the pituitary gland that secretes a hormone called prolactin. Prolactinomas are caused by too much prolactin in the blood or by pressure of the tumor on surrounding tissues. Prolactin stimulates breast milk during pregnancy. A mother’s prolactin levels fall unless she breast feeds her infant, to maintain milk production and raise prolactin levels.

Prolactinoma can be classified based on size as a Microprolactinoma (<>10mm diameter). The causes of pituitary tumors remain unknown although research continues. Pituitary tumors are not genetically passed to offspring. The most common cause of Prolactinoma is prescription drugs.

Symptoms and Diagnosis

Symptoms men and women experience are headaches and loss of vision. Women may observe an unexplained milk secretion, disruption of their menstrual cycle, or infertility. Men may have impaired sexual function and in rare cases, milk secretion.

The diagnosis is usually based on visual difficulties and or excess hormone secretion. Tumors which cause visual difficulty are usually macroadenomata (>10mm). The tumors that secrete more than one hormone are mostly a combination of GH and prolactin. Stress should be ruled out before the diagnosis of prolactinomas is given. Exercise can reduce stress and prolactin levels.

Treatment

Prolactinoma are treated by drugs that will decrease the tumor size and return prolactin levels back to normal in approx. 80% of patients. The doctor will also request and MRI scan for detecting pituitary tumor size and periodically repeat MRI scans to check the tumor progression and the effects of therapy. Radiation Therapy can be used for treatment of large tumors (Macroprolactinomas). Surgery depends on the size of the tumor also as well as the experience and skill of the neurosurgeon. Surgery should only be considered if medical therapy cannot be tolerated.

Macroprolactionamas may require more aggressive treatment if they continue to grow. The growth rate is different for every individual. Microprolactinoma will not show any signs of growth after 4-6 years in 95% of the cases. Therefore, regular monitoring by a specialist is recommended.

For more information go to: http://en.wikipedia.org/wiki/Prolactinoma

Semicircular Canal Abnormalities

Causes of BPPV

Benign Paroxysmal Positional Vertigo (BBPV) is caused when otoconia, tiny calcium crystals dislodge from the utricle. The utricle is a sensory organ in the inner ear. These dislodged otoconia flow freely in the fluid filled spaces of the semicircular canals. Sometimes they may form a large clump. Due to the heavy clump, the otoconia usually fall into the posterior semicircular canal, the lowest part. Whenever the head changes positions, these tiny calcium crystals move in the semicircular canals causing dizziness, like the world is spinning around you. These are several causes for BPPV, some which include:
Vestibular migraines
Head in the same position for a long time
Slight to abrupt movement of head
Walking or riding on rough trails
High intensity aerobics
Labyrinthine conditions-viral or vascular
Mild to severe head trauma

Symptoms of BPPV

Positional Vertigo is one of the most common types of dizziness experienced by adults. These episodes are usually brief, but can be severe. Sometimes nausea follows positional vertigo. The lifestyles of many sufferers are restricted from slight movement during sleep to its most severe condition that immobilizes a person. Other motion sickness like symptoms occur whenever a patient turns over in bed or get out of bed, tilt their back to look up high, or tip their head to look down low. The onset of BPPV may be frightening and cause the patient to fall and they may even think they’re having a stroke. The usual course of this illness is a gradual lessening of symptoms over a period of time from weeks to months to years.


Diagnosis of BPPV & Treatment:

The diagnosis of BBPV is made by characteristic symptoms and by observing the nystagmus. The jerking of the eyes when the position of their head is changed. The doctor will try to provoke the symptoms to see the nystagmus for a thorough diagnosis.

The treatment of BPPV is usually physical therapy maneuvers and or exercise programs designed to remove the stones from the semicircular canals. Once the stones are out, they are absorbed naturally over the course of days to weeks. But there’s always the risk of the stones falling back into the semicircular canals and getting stuck again. In some cases a hand held vibrator is applied to the bone behind the ear to help dislodge the stones. If the posterior or lateral canals are involved with stones, slightly, different therapy maneuvers are used. It is based upon the same principle, with respect to the pull of gravity to move the stones out of the offending semicircular canal. BPPV of the anterior canal is very rare because these stones easily fall out on their own due to their location (at the top of the inner ear).

Usually no medications are given for BPPV, unless required for a patient with severe nausea or vomiting. Surgery is rarely performed to plug the posterior semicircular canal to prevent otoconia from moving within the canal. “The past surgical solution was not worth the risk,” notes Timothy Molony, a neuron-otologist at the Ochsner Ear Institute. The surgical plugging procedure cures the problem, but it may carry some risks-like hearing loss. About 20%-30% BPPV patients are treated again due to the symptoms recurs within the first week. Over the long term, BPPV recurs about half the time. In about 70%-80%, a cure is immediate. BPPV can also be diagnosed and successfully treated with no pills, no test, no special equipment, and no surgery.

For more information go to: www.encyclopedia.com and www.hopkinsneuro.org/vestibular/disease.cfm

Meningioma Tumor

What is Meningioma?

A meningioma is a tumor that develops from the mininges. Meningis are the membrane that surrounds the brain and spinal chord. 10% of Meningioma are malignant and 90% are benign tumors. These benign tumors can grow and affect the brain causing disabilities and death. Some of these benign tumors grow slow and reach a large size before symptoms are noticed. While others grow unpredictably fast, depending upon location. Multiple meningiomas may grow in different parts of the brain and spinal cord simultaneously or at only one site. Meningiomas are the most common type of primary brain tumor which originates in the central nervous system, approx. 27%.

Who’s at risk?

Middle aged people between 40 and 70 are most prone to develop Meninigiomas. Also they are more common to women than men. The ratio is about 3 to 1 in the brain and 6 to 1 in the spinal cord. Children rarely get meningiomas, approximately 1.5%.

Symptoms and Diagnosis

Symptoms of meningioma vary depending size and location. They are: (1) memory loss, (2) unbalance, (3) headaches, (4) vision loss, (5) arm or leg weakness, (6) carelessness, and (7) seizures. Patients may have some of these symptoms for a long time before being diagnosed. Doctors usually have their patient scheduled for a CT and/or MRI scan with contrast. MRI images better to show pathology. But CT can show boney detail (such as if the tumor invades the bone or if it’s calcified).

Treatment Outcome

The treatment for clinical diagnosis meningiomas is surgical resection/removal. Incomplete removal of tumors due to location or age may cause the tumor to reoccur. The residual tumor cells can actually begin to grow again. Younger patients have an increased chance of survival. Nevertheless, older patients, otherwise in good health, have a pretty good outcome. Survival rates show a big difference when grouped by type with atypical being the highest followed by benign and then malignant.

For more information log on to: www.brighamandwomen.org/neurosurgery/Meningioma