CT scanner

A CAT scan or a CT scanner machine is a large machine in the shape of a doughnut. The patient is made to lie on a couch. The couch can slide backwards and forwards. The couch slips into the center of the doughnut shaped machine which takes the x-ray images around the body. The actual procedure takes anywhere from half an hour to one and half hours. During the CAT scan procedure, the patient's bodily movement has to be minimal and should remain as still and quiet as possible. This significantly helps to increase the clarity of the x ray images.

Some CAT scans need special preparations before hand. The preparation may vary according to the type of scan taken.

• For abdominal CT scans, the patient is asked not to eat or drink anything after midnight, the night before the scan. A 'contrast medium' has to be drunk or an injection of 'contrast medium' is administered to the patient. Some of this liquid can be taken at home but more of the liquid is taken in the x ray department before the scan. The contrast medium makes the digestive system show more clearly in the scan. This does not have any side effects.
  
• For CT scans of the head, the patient is given an injection of 'contrast medium' dye beforehand to make the scan clearer.
  
• For CT scans of the chest, the injection of 'contrast medium' dye is administered beforehand to show up the tissues in the area containing cancer or blood vessels more clearly.
  
• For pelvic CT scans, the patient is asked not to eat or drink after midnight of the night before the scan. An injection of 'contrast medium' is given before the scan. An injection of a drug to slow down the movement of the pelvis area is given so that there will be distortion during the time of the scan.
  
• For a rectal scan, the patient is given an enema occasionally. This makes the outline of the bowel stand out more during the scan.
  
• In certain detailed scans of the bowel called virtual colonoscopy, the patient is asked not to eat or drink for 36 hours before the study and two doses of a strong laxative the day before the scan is advised.
  

Spiral CT Scan

CAT scan technology continues to evolve and promises better quality pictures and patients safety. Newer type of CT scans is known as Spiral or helical CT scan. It is called Spiral scan because the X-ray beam rotates around the patient during the scan in a spiral shape. This helps to give a continuous picture with no possible gaps between the 'slices' of the scan. The 'spiral' or 'helical' CAT scans provide more rapid and accurate visualization of the internal organs. They give more detailed pictures of the organs and tissues including blood vessels. The Spiral CT scans are faster than a normal CT scan. Many trauma centers have started using such scans for more rapid diagnose of internal injuries after serious body trauma.

Ganglioglioma

First described by CB Courville in 1930, Ganglioglioma comes from the Greek work 'ganglion' meaning know, and the Greek word glia meaning glue and the Greek word oma meaning tumor. Strung together, the words mean 'glue knot tumor'. Ganglioglioma is a rare type of tumor that originates from nerve cells and develops in the central nervous system. The growth of the tumor and its symptom may vary depending on its exact location and size.

Ganglioglioma accounts for 2% of all primary intracranial tumors and up to 10% of primary cerebral tumors in children. Ganglioglioma can occur anywhere in the brain and rarely in the spine as well. Most Gangliogliomas are located on the sides of the brain by the ears and in children about 70% are located above in a part in the brain known as the tentorium - a membrane that separates an area in the back, lower part of the brain known as cerebellum, from an area in the back, upper part of the brain known as occipital lobes. Ganglioglioma can also occur in the brain stem, located below the cerebellum that controls many important motor, sensory and reflex actions.

Symptoms

The signs and symptoms depend on the location of the tumor and how fast it can spread, depending upon the age of the patient. In those above ages 10-20, symptoms include:

• Seizures
  
• Involuntary muscle movements
  
• Decreased awareness of the environment.

If Gangliogliomas appear in the ear lobes, it can lead to seizures and symptoms such as:

• Loss of awareness
  
• Abnormal sensations
  
• Feeling of being detached from oneself
  
• Involuntary muscle movements

If Gangliogliomas are present in the cerebellum, signs and symptoms include:

• Impaired motor coordination
  
• Headache
  
• Buildup of cerebrospinal fluid in the brain

Causes

Gangliogliomas are caused by abnormal glial cells. Glial cells support and maintain other cells. Gangliogliomas are partly made of neurons or nerve cells in various degrees of abnormality. In Gangliogliomas are also found supportive tissue known as stroma, which contain fibers and blood vessels. Fibers are flexible, threadlike objects found outside the cells. In Gangliogliomas are neurons, glial cells and stroma in abnormal shape, size and appearance. The more the cells change in structure, size and appearance; the more harmful the tumor is.

Diagnosis

Initially the seizures associated with Ganglioglioma lead a patient to seek medical help. The doctor uses various techniques to diagnose the cause of the seizures. Pictures of the brain are taken and CT scans done to get clear and detailed pictures. MRI scans are sensitive and specific at detaching a tumor and when contrast is injected into the person's body during the scan. About 50% of Gangliogliomas are detected when contrast is used. MRI scans can also detect if there are any cysts in an abnormal lump, swelling or sac that contains fluid and is covered with a membrane.

But it is not until a sample of the tumor is removed during surgery that it can be tested in a laboratory and definitively stated that it is Ganglioglioma. In a laboratory abnormal neurons are stimulated and the irritation produces a protein called synaptophysin and glial fibrillary acidic protein. There are special stains applied to the neurons in the lab to detect the presence of these proteins. However regular x rays do not help in diagnosing Gangliogliomas as they are best at detecting bones and can only detect if calcium is near the Ganglioglioma.

Gangliogliomas are common before age 20 and about 60% of people who are diagnosed with Ganglioglioma are adolescents and adults younger than age 30. However, even those as young as 2 or as old as 70 have been known to develop Ganglioglioma. It affects equal numbers of males and females. In the US approximately 1 to 2% of brain tumors are Gangliogliomas. About 10% of all primary brain tumors in children are Gangliogliomas.

Treatment

Surgery is most often done to remove Ganglioglioma tumor. After the tumor is removed, radiation therapy is not needed unless the tumor shows signs of growing back, which is rare. Radiation is aimed at tumors to destroy or weaken them. Prognosis of people with Ganglioglioma is excellent as it is easy for surgeons to remove them as they are typically found in one place and can be separated from the brain tissue. Most get cured after surgery and chance of tumor coming back after it has been totally removed is rare.