Computerised Tomography

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CT (computed tomography), sometimes called CAT scan, uses special x-ray equipment to obtain image data from different angles around the body, and then uses computer processing of the information to show a cross-section of body tissues and organs.

CT imaging is particularly useful because it provides detailed information on head injuries, brain tumor, other brain diseases and also can show several types of tissue -- lung, bone, soft tissue, and blood vessels -- with great clarity. It is also used to plan and properly administer radiation treatment for tumors and to guide biopsies and other minimally invasive procedures and also to measure bone mineral density for the detection of osteoporosis. It is also useful in dental radiology.Using specialized equipment and expertise to create and interpret CT scans of the body, radiologists can more easily diagnose problems such as cancers, cardiovascular disease, infectious disease, trauma, and musculoskeletal disorders. CT of the body is a patient-friendly exam that involves little radiation exposure.

The following newer modalities are available

• Three Dimensional CT
• Dental CT
• Real-time Multiplanar Reconstructions
• High-resolution CT
• Dynamic CT
• Spiral CT

MULTI SLICE SPIRAL (CT)

Multi Slice Spiral (CT) is future of CT imaging and has numerous advantages over conventional CT.

Sub Second performance ensures rapid scanning and reduced scan time (especially useful for pediatric and trauma cases)

Spiral CT allows for volumentric acquisition of data and subsequent 3D reconstruction of the acquired data.

Most Spiral CT application are a combination of the superior imaging and software processing and software configuration includes options, like

• Osteo CT : Quantitative determination of Bone Mineral Density of the spine for detection of Osteoporosis, especially useful in Women, after age of 40.
• Dental CT : Reformatting of panoramic and paraxial section through lower and upper jaw for analysis in implantation surgery.
• Real Time MPR Reconstruction : Multiplanar reformatting of data in secondary perspective in real time.
• CT Angiography : Allowing for display of vessels, vascular anomalies, aneurysms, plaques and stenosis.
• 3D SSD Volumentric Reconstruction : Three dimensional display of surfaces, particularly useful for reconstructive surgery, orthopaedic cases especially fractures of hip, spine, knee and shoulder.
• Cranial Applications : Due to short scan time spiral CT is useful in uncooperative patients with head injury or stroke. Even in paediatric patients with spiral CT the need of sedation can be avoided. Additionally the amount of intravenous contrast can be reduced.

X - RAY

X-rays are electro-magnetic radiation, which are produced by special machines called X-ray machines. These cannot be seen, felt or heard. Different parts of the body behave differently with X-rays. Structures such as bone absorb X-rays, whereas air in the lungs lets all X-rays pass through.

Most people are familiar with common x-ray procedures for chest radiography. Approximately half of all radiographs obtained in medical institutions are images of the chest. A chest x-ray is usually done for the evaluation of lungs, heart and surrounding anatomy. Pneumonia, heart failure, and lung cancer can be diagnosed or suspected on a chest x-ray, along with other less common conditions. X-rays are also used to diagnose disorders in other parts of the body - especially bones, and also by using special contrast material (dyes), barium etc. There is no risk involved while performing a radiograph, x-rays are however not performed in early and mid pregnancy due to possible harmful effects of radiation on foetus.

ULTRASOUND (USG)

Ultrasound (USG) or sonography involves the sending of sound waves through the body. Those sound waves are reflected off the internal organs. The reflections are then interpreted by special instruments that subsequently create an image of anatomic parts. No radiation is involved in ultrasound imaging.

Ultrasound is useful in detecting various musculoskeletal disorders such as tendon tear and inflammation, soft tissue masses and joint lesions. It is also useful in detecting various congenital lesions of the brain, useful in obst.-gynec imaging, pelvic ultrasound examinations of the uterus and fetus. Ultrasound imaging is used extensively for evaluating the eyes, heart, and blood vessels, and can help a physician determine the source of pain, swelling, or infection in many parts of the body. It can also be used to guide procedures such as needle biopsies, Ultrasound is now being used to image the breasts and to guide biopsy of breast cancer.

Doppler ultrasound is a special technique used to examine blood flow. Doppler images can help the physician to see and evaluate: blockage of blood flow, such as clots, build-up of plaque inside the vessel, congenital malformation.

Ultrasound imaging is a painless, low cost examination, widely available and easy to use. US imaging uses no radiation, and is the preferred image modality for diagnosis and monitoring of pregnant women and their unborn infants.

MAMMOGRAM

Mammography is a specific type of imaging that uses a low - dose x-ray system and high-contrast, high-resolution film for examination of the breasts. Successful treatment of breast cancer depends on early diagnosis. Mammography plays a central part in early detection of breast cancers. Mammography can show changes in the breast up to two years before a patient or physician can feel them.

Mammography is used to diagnose breast diseases in women. The use of screening mammography can assist in the detection of disease even if you have no complaints or symptoms.

Women aged 40 and older should get annual mammograms. Women who are at increased risk due to a genetic history of breast cancer, or who have had breast cancer, may need to get mammograms at an earlier age.

The initial two mammography images themselves are not always enough to determine the existence of a benign or malignant disease with certainty. If a suspicious finding or spot is seen, the radiologist may recommend further diagnostic studies. If a doubt exist on the diagnosis, this test can be combined with sonography (sono-mammography) or may be used to localise a lesion (tumour) by a special wire technique to enable a core biopsy.

COLOUR DOPPLER

Doppler ultrasound is a special technique used to examine blood flow. Doppler images can help the physician to see and evaluate: blockage of blood flow, such as clots, build-up of plaque inside the vessel, congenital malformation. With knowledge about the speed and volume of blood flow gained from an ultrasound image, the physician can often determine whether a patient is a good candidate for a procedure such as angioplasty.

Doppler ultrasonography is application of diagnostic ultrasound used to detect moving blood cells or other moving structures and measure their direction and speed of movement. The Doppler effect is used to evaluate movement by measuring changes in frequency of the echoes reflected from moving structures.
The movement of the embryo or fetus and fetal heart can be seen as an ongoing ultrasound "movie."