Central Retinal Artery Occlusion

Central retinal artery occlusion (CRAO) is a medical condition that is characterized by loss of vision on account of the blockage of the central artery of the retina. A clot from the carotid artery or the heart is usually the cause for the sudden flow of blood to the retina. Patients suffering from hypertension or carotid artery disease or diabetes are likely to suffer this condition. Arteriosclerosis is another likely cause for Central retinal artery occlusion. Due to the blockage of the retinal central artery, there is sudden and painless loss of vision. Another less severe condition is when a smaller branch artery to the retina gets blocked. This leads to loss in vision that is not as severe as in the case of CRAO.

If not attended to immediately, central retinal artery occlusion can leave a person permanently blinded. It is essential to restore retinal blood flow. An opthalmologist may try to reduce the pressure in the eye with glaucoma agents. The embolus is moved from the central retinal artery to a branch artery. A surgical procedure whereby a small amount of fluid is drawn from the eye is carried out sometimes. This can seek to lower the pressure in the eye. Laser treatment is also done to reduce swelling and improve vision in the case of branch vein occlusion. But in most cases, it is not easy to restore normal vision.

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 xrays 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.