Panoramic X ray

The Panoramic x-ray or Panorex as it was initially called is considered the 'work horse' of dentistry. The Panorex is a large single x ray film that shows the entire bony structure of the teeth and the face. It covers a much wider area than a traditional intra oral film showing structures outside of their range including sinuses, temperomandibular joints as well as the position of the wisdom teeth. The panoramic x ray has the ability to scan the region of oral pharynx and surrounding tissues thereby increasing the dentist's diagnostic capabilities. The uninterrupted panoramic film is the most commonly used for obtaining clearly portrayed image of orofacial structures in dentistry. Other dental X-rays include:

Bitewing x ray uses the least amount of radiation. It shows the upper and lower back teeth in a single view. They are used to detect decay between the teeth and to show how well the upper and lower teeth line up. Bitewing also indicates bone loss and the presence of severe gum disease or dental infection.

Periapical x rays show the entire supportive system of the tooth from the exposed crown to the end of the root and bones. They are used to detect dental problems below the gum line or the jaw. They also help to detect impacted teeth.

Panoramic x rays belong to the broad category of x rays called tomographs. The amount of radiation needed to expose a panoramic film is about the same as the radiation needed to expose two intra oral films. It is advised to use lead apron during panoramic x ray. In panoramic x ray, the x ray source passes around the patient and behind their head at a slight upward angle. Use of a lead apron helps in optimal prevention of the patient's body from scatter radiation of the panoramic x ray beam. Special panoramic lead aprons are available that cover both the back and front of the patient without interfering with the path of the X ray beam.

• Cysts, tumors, bone irregularities are also revealed in panoramic x ray.
  
  
• Impacted teeth that may be buried deep inside the jaw bone are shown in panoramic x ray.
  
  
• Panoramic x ray is usually taken when the wisdom teeth (third molars) are being evaluated.
  
  
• Panoramic x ray is used in dental implant surgery as it clearly reveals the possible complications in mandibular nerves.
  
  
• Panoramic x ray can also identify some not so common problems such as calcification within the carotid artery that may be indicative of a potential stroke.
  
  
• Panoramic films are especially good for forensic purposes in the identification of otherwise unrecognizable bodies after plane crashes or mishaps.

Chest x ray

Chest x-ray is a regular diagnostic test that throws light on the condition of the lungs, heart and chest wall. Chest x-ray reveals possible lung cancer, emphysema, heart failure and pneumonia. Heart irregularities and CHF may be visible on a chest X ray. Any pleural effusions may be detected through a chest x-ray. The patient must wear loose fitting gown and remove any metal objects from clothing. In most cases, chest x-ray of frontal or posteroanterior view is taken. The patient has to take a deep breath so as to ensure a good quality chest x-ray image. There is no discomfort. Pregnant women must not undergo chest x-ray. But some conditions may not be easily diagnosed with a chest Xray, such as pulmonary embolism or some cancers. In such cases, CT scan of chest is used for further clarification. Abnormal findings on chest X-rays can range from pneumonia and tuberculosis to lung tumor or collapsed lung. Osteoporosis or fracture of ribs or spine can be detected.

Venogram

An x ray taken of the blood flow through the veins in certain area of the body is called venogram. This is done by inserting a certain special dye into the veins so that it can be seen clearly on the X ray image. This is done to study the condition of the veins and the valves in veins.

Venogram can show the veins in the legs, arm, and pelvis, veins leading to the heart or leaving the kidneys. The patient is advised not to eat at least four hours prior to venogram. You may drink only clear fluids for four hours before the test. It is better for the patient to apprise the doctor on certain things as given below before a venogram is done:

• if she is pregnant
  
• is allergic to certain drugs
  
• has bleeding problems or has taken blood thinning medications
  
• has asthma
  
• has severe allergic reactions
  
• has kidney problems
  
• has diabetes and is on medication.

The patient is required to sign a written consent for this procedure. Venogram is done in a hospital x ray department by a radiologist and an x ray technologist. A nurse is also present. The patient is asked to remove any jewelry before the test. Most of the clothes need to be taken off. A gown is given to the patient to wear during the test. The patient is advised to urinate just before the test begins. The patient is made to lie on a table and a tilting x ray table is used to study the legs. The patient is fitted with safety straps to lie still even if the table is tilted.

In case of a leg venogram, the patient is asked to relax the leg and keep it still during the x ray. An elastic band is put around the leg as this enables the veins of the foot fill with blood. The dye is inserted into the vein on the top of the foot. If the veins of the pelvis are to be studied, the dye is placed in a vein on the groin and for an arm venogram; the dye is put into the vein on the top of the hand or in the arm. After inserting the dye, x ray from different angles/views are taken.

After the x rays are taken, saline is inserted into the vein to help flush out the dye. To prevent blood clot, sometimes a blood thinner is put into the veins. The duration of the procedure is about 30 to 45 minutes. You will feel a quick pinch when medicine for numbness is given. A warm flush or a metallic taste in the mouth may be felt when the dye is put into the vein.

Venogram has certain risks which includes allergic reaction to the dye, infection or damage to the veins, deep thrombosis of the veins in very rare cases, kidney problems, and damage to cell tissue due to radiation. It is better to call the doctor immediately if after the test the patient has a fever or suffers increasing pain, redness and swelling in the arm or leg. As for results of venogram, if the dye moves quickly and evenly through the veins, the results are normal. If the flow is blocked or slowed, then the results are abnormal. This means, there is a blood clot or some other problems such as damage in the vein.