Wednesday, April 15, 2009

Scoliosis

*What is Scoliosis?*
Scoliosis is an abnormal lateral curvature of the spine. Some curvature is normal to help the upper body maintain proper balance and alignment over the pelvis. It usually occurs in children ages 10 to 15. Scoliosis affects 2% of women and 0.5% of men in the general population. There are many causes of it including congenital spine deformities, genetic conditions, neuromuscular problems, and unequal length of the limbs. Other causes are cerebral palsy, spina bifida,and  muscular dystrophy. Although there are many causes associated with it, 80% of scoliosis cases have no known cause. 

*Symptoms*
There are several warning signs of scoliosis. They include shoulders at different heights, the head not centered above the pelvis, the rib cages at different heights, an uneven waist, and leaning to one side.

*Diagnosis*
There is an easy test to see whether or not you have scoliosis. It is called the Adam's Forward Bend Test. For this, you lean forward at the waist 90 degrees, and it is easy to tell if you have scoliosis by the asymmetry of the trunk or any abnormal spine curvatures. If an abnormality is noted, an x-ray will be performed.

*Treatment*
When determining the type of treatment there are many things that must be taken into consideration. These include the spinal maturity, the degree and extent of the curvature, the location of the curve, and the potential for progression. Once these have been determined there are three main types of treatment. They are observation, orthopaedic bracing, and surgery. 

This is a coronal T2-weighted MRI image showing scoliosis in the thoracic vertebrae.
http://www.scoliosisjournal.com/content/figures/1748-7161-3-3-15-l.jpg

Carotid artery aneurysm

*What is a Carotid artery aneurysm?*
An aneurysm is a bulging or ballooning in the wall of a blood vessel. It is caused when a portion of the artery wall weakens. The artery wall grows progressively thinner, increasing the likelihood that the aneurysm will burst.

*Symptoms*
The symptoms of a carotid artery aneurysm include transient ischemic attacks or stroke. Other symptoms are facial swelling, hoarseness, or difficulty swallowing from the aneurysm applying pressure to surrounding structures. 

*Treatment*
If the aneurysm is small and is not causing any problems, waiting and watching may be the best option. A CT or MRI may be ordered every 6 to 12 months to watch the aneurysm for signs of changes. If it needs to be treated there are a couple of different options. One option is surgical repair in which a bypass is made from the normal artery below the aneurysm to the normal artery above the aneurysm. Another option is endovascular stent grafting. The physician will enter an artery in the groin and insert a stent in the area of the aneurysm, allowing the blood to flow freely.

This is a coronal CT image showing an aneurysm that is eroding the sphenoid bone and protruding into the sphenoid sinus. 
www.radpod.org/2007/08

Sunday, March 22, 2009

Goiter

*What is a goiter?*
A goiter is the name of the condition when the thyroid gland grows larger than normal. The thyroid is located at the base of the neck, just below the Adam's apple. The most common cause of a goiter is an iodine deficiency, but in the United States where we use iodized salt, it is more often due to the over or under production of thyroid hormones. It can also be caused from many other things including pregnancy, Graves Disease, thyroid cancer, and inflammation. 

*Symptoms*
Not all goiters will cause symptoms to appear. When symptoms do occur they may include visible swelling at the base of the neck, a tight feeling in the throat, coughing, hoarseness, difficulty swallowing, and difficulty breathing.

*Diagnosis*
A doctor may be able to notice a goiter simply be feeling the area of the thyroid while a person swallows. If he cannot feel it, he may order another test to be done. These can include a hormone test in which blood is drawn and tests are done to see if the hormones produced by the thyroid are high or low, an ultrasound of the thyroid, or a thyroid scan in which a radioactive isotope is injected to better visualize the thyroid. 

*Treatment*
Treatment of a goiter depends on its size. If it is not large and it is not causing any difficulties swallowing or breathing, observation may be best to make sure it doesn't grow larger. Medications can also be used to treat things such as hypothyroidism in which the thyroid overproduces a hormone, causing the goiter. Surgery can also be done to remove part or all of the thyroid if it causes difficulty breathing or swallowing. Another option for treatment is radioactive iodine which is taken orally and reaches the thyroid via the bloodstream. It destroys thyroid cells, diminishing the size of the goiter, but it can also cause an underactive thyroid gland.

This is an example of a goiter. 


This is a sagittal view of a person with a goiter. It is pointed out with the red arrow.


http://www.learningradiology.com/caseofweek/caseoftheweekpix2006/cow231arr.jpg

Arteriovenous Malformation

*What is Arteriovenous Malformation?*
Arteriovenous Malformations(AVMs) are defects of the circulatory system that are believed to arise during embryonic development or shortly after birth. The are comprised of tangled arteries and veins. The presence of an AVM disrupts the normal function of these arteries and veins, which is taking blood away from the heart and returning it to it. An AVM can develop in many different areas, but those in the brain and spinal cord can have widespread effects on the rest of the body. AVMs of the brain and spinal cord are believed to effect approximately 300,000 male and female Americans.

*Symptoms*
Most people with AVMs don't experience any symptoms and they are only detected during an autopsy or during treatment for an unrelated disorder. Symptoms only tend to occur when the damage from the AVM to the brain or spinal cord reaches a critical level. For those people that do experience symptoms, seizures and headaches are the most generalized. Other symptoms include muscle weakness or paralysis in one part of the body, a loss of coordination, dizziness, visual disturbances, and memory deficits just to name a few.  

*Diagnosis*
Angiography provides the most accurate pictures of blood vessel structures in an AVM. Contrast is injected into an artery and it highlights the blood vessels. CT and MRI can also be used to detect the presence of an AVM, as well as MRA and CTA which provides three dimensional representations. 

*Treatment*
Treatment is done on an individualized basis. Medication can be used to alleviate general pain that goes along with an AVM, such as back pain, headaches, or seizures. A few other options, if possible, are surgery or focused radiation therapy.

The first image is a CT scan showing a hemorrhage. The cause was unknown at the time, but after removal an AVM was found. The second image is the cerebral angiogram of the same patient done after the AVM was found in surgery. 

     
www.brain-aneurysm.com/avm.html

Nasal Polyps

*What are Nasal Polyps?*
Nasal polyps are teardrop-shaped growths on the lining of your nasal passages or sinuses. They are typically noncancerous. They are formed when the mucous membrane or your nasal passage and sinuses become chronically inflamed. Small polyps may go unnoticed, but larger polyps can block your nasal passage or sinuses and cause breathing difficulties, a loss of your sense of smell, and frequent sinus infections among other problems. They are seen more in adults, particularly those with asthma, frequent sinus infections, and allergies. Children with cystic fibrosis often develop nasal polyps as well. 

*Symptoms*
As mentioned earlier, small polyps will generally go unnoticed. On the other hand, if you have several polyps or large polyps you may experience a few different symptoms. Some of these are: runny nose, persistent stuffiness, postnasal drip, loss of sense of taste, decreased or no sense of smell, facial pain or headache, snoring, and itching around your eyes. As you may notice, some of these symptoms mimic the common cold, but if these symptoms last for more than 10 days you should see a doctor. 

*Diagnosis*
If you go see a doctor he may be able to tell by your answers to different questions about your symptoms, along with a general physical exam and examination of your nose if you have nasal polyps or not. Some polyps may be visible with a simple lighted instrument. If not, he may order a test for you to determine if you have polyps. These tests include a nasal endoscopy, which is a narrow tube with a magnifying glass or camera which is guided into your nasal cavity, a CT scan, or an allergy test to see if an allergic reaction is causing chronic inflammation. If a child presents with these symptoms, the doctor may prescribe a cystic fibrosis test. Cystic fibrosis affects the glands that produce mucus, tears, sweat, saliva, and digestive juices. 

*Treatment*
The goal in the treatment of polyps is to decrease the size of the polyps or to eliminate them and treat whatever is causing them to appear. Medications is one treatment a doctor may try. Nasal corticosteroids are often prescribed through a spray to decrease inflammation. It may also eliminate them completely. A doctor may also prescribe drugs to treat the conditions that are causing the chronic inflammation. If medication does not work , surgery may be required. There are two types of surgeries that are typically performed. One type is Polypectomy, which is where a small suction device is used to remove small polyps. Another surgery is Endoscopic sinus surgery, which removes the polyps and corrects problems with your sinuses that may be causing the polyps.

The image on the left is an Axial CT image and the image on the right is a Coronal CT image. They demonstrate nasal polyps shown by the arrows. 


http://www.brown.edu/Courses/Digital_Path/systemic_path/hn/nasalpolyp3.html

Thursday, February 26, 2009

Coats' Disease

*What is Coats' Disease?*
Coats' Disease, also known as Exudative Retinitis, is a rare condition that occurs in children and young adults, usually males. It is a progressive condition of abnormal development of the retinal capillaries that usually occurs in the first 10 years of life. It is a gradual process that affects central vision, usually just in 1 eye. The retinal capillaries nourish the retina, which is where light is converted into electrical signals. These signals pass along the optic nerve and to the brain where they are converted into sight. There are no known causes for Coats' Disease at this time.

*Symptoms*
The main symptom of Coats' Disease is loss of central or peripheral vision. Other symptoms include sensitivity to light, cloudy vision, and a white patch on the pupil. This is a picture of a young boy with Coats' Disease. Notice the yellowish color of his right pupil. This is caused by a build up of cholesterol in the retinal capillaries leaking into his eye.

http://www.daisyseyecancerfund.org/Photos/Symptoms/coats1.gif

*Treatment*
If it is caught early enough, vision to the affected eye may be saved. Many times the children are not able to communicate their problems or may not notice them soon enough. Their are 5 different stages that Coats' Disease is broken into.
~Stage 1: There is a high probably that vision can be saved if caught in this stage, although as mentioned earlier, the child typically will not be able to understand what is going on at the time. Although catching Coats' Disease in this stage is unlikely, it can be treated with Laser Therapy if it is caught.
~Stage 2: There is a good chance that vision can be restored in this stage, depending on if the fovea has been affected or not. The treatment during this stage is Laser Therapy or Cryotherapy. Cryotherapy uses extreme cold to freeze and destroy dead tissue.
~Stage 3: In this stage the retina has detached and Laser Therapy or Cryotherapy can still be used. Cryotherapy may be more effective here if the detachment is shallow. If the detachment is more advanced surgery may be required.
~Stage 4: There is not really any chance of vision recovery in this stage, but laser therapy would be the only attempt to stop the leakage. Many times if the pain is severe enough, removal of the eye may be necessary.
~Stage 5: This stage results in total blindness that is irreversible. 

This is an Axial CT slice showing total retinal detachment in the left eye.


http://download.imaging.consult.com/ic/images/S1933033207752692/gr1-midi.jpg

Prolactinoma


*What is Prolactinoma?*
The pituitary is a small gland in the endocrine system located at the base of the brain and sits in the sella turcica. Don't let its small size fool you though! It influences nearly every part of your body! Some of the things that it helps regulate are growth, reproduction, and blood pressure. The pituitary also produces a hormone called Prolactin which stimulates breast milk production in females, but this type of tumor can also occur in men. Although the cause of pituitary tumors is yet unknown, Prolactinoma is the most common type of pituitary tumor. These tumors are almost always noncancerous, but they can increase in size. They tend to occur more commonly in women rather than men, and they are very rare for children. People with Prolactinomas tend to develop them under 40 years of age, but they tend to develop in younger ages for women and older ages for men.

*Symptoms*
The symptoms of Prolactinoma result from excess prolactin in the blood and from pressure on the surrounding tissues. Because the area that the pituitary is housed in is so small, when the tumor grows it can compress your optic nerve and cause visual disturbances. Other symptoms that can occur in both males and females are headaches and infertility. In women, missed or irregular menstrual cycles or  production of breast milk when not pregnant or breast feeding are also common symptoms. In men, erectile dysfunction and uncommonly enlarged breasts are key symptoms. Women usually tend to notice a problem earlier than men because of the missed or irregular menstrual cycles, whereas men don't really seem to notice until the tumor gets much larger and presses on the optic nerve causing headaches and vision problems.

*Diagnosis*
The most sensitive study available to detect a pituitary tumor is MRI, although a CT scan can also be done. Also, your doctor may test prolactin levels in your blood or he may also perform a vision test to see if the growth of the tumor has impaired your vision.

*Treatment*
The 2 main treatments for Prolactinoma are medication or surgery. Medication is usually a long-term process that reduces the levels of prolactin in the blood and may also shrink the tumor. If medication shrinks the tumor and your prolactin levels remain at a normal level, you may be able to stop taking the medication. Surgery is typically done if the medication is not successful or is not tolerated by the patient. It may also be necessary to relieve pressure on the optic nerves, in which case removal of the tumor may be necessary. The most common surgery performed is removing the tumor through the nasal cavity.

This is a sagittal T1 weighted MRI image of a Prolactinoma in a 27-year-old female who was 32 weeks pregnant. She complained of headaches and vision problems.

http://radiographics.rsnajnls.org/cgi/content-nw/full/27/1/95/F12B

This is the coronal T1 weighted MRI image of the same 27-year-old female.


http://radiographics.rsnajnls.org/cgi/content-nw/full/27/1/95/F12A