Information For The Patients

Tuesday, December 14, 2004


Computed Tomography (CT)
Computed tomography (CT) or CAT scan, uses a rotating X ray tube and computer to obtain thin sections of the body. It is especially useful in cases of head injury and stroke. It is best investigation to detect acute hemorrhage and calcification anywhere in the body. It is also good to evaluate cortical bone.
Although it is non-invasive it uses ionizing radiation. although three dimensional reconstructions are possible it doesnt give direct multiplanar images.
It may require use of an iodianted contrast which may be toxic to kidneys in very high doses and can cause idiosynratic reactions in some (especially asthmatics, diabetics, cardiac patients etc). Metallic objects like coins, dentures etc may cause artefacts in the images.

Women should inform if there is any possibility that they are pregnant, as the examination involves radiation which is harmful to the fetus.
Further reading-

Ultrasound in pregnancy

Ultrasound - Obstetric

Ultrasound imaging or sonography is based on the priciple of piezo-electric effect.Sound waves are produced by a piezoelectric crystal and images are produced by sound waves being reflected by various organs in the body.It does not use any ionizing radiation.
It is used in pregnancy to determine following things-
Number of fetuses, lie, presentation, fetal maturity, placental localiztion, liquor and congenital anomalies.
Evaluation of early preganancy requires a full bladder (oops!!!) and it is not essential for later stages of pregnancy. Nowadays even three dimensional and four dimensional (3D in real time) are also available which can give 3D representations of fetal face, spine and various congenital anomalies and give the parent an oppurtunity to decide after seeing the baby.

Doppler US can also be used especially in high risk mother like Pregnancy induced hypertension and IUGR to assess utero-placental and fetal blood flow dynamics.

Please note-ultrasound cannot identify all fetal abnormalities. It can determine the sex of the baby (but telling the sex of the baby is illegal in India!!)
Further reading-

Monday, December 13, 2004

MRI for patients

Magnetic Resonance Imaging (MRI)

Magnetic resonance imaging, or MRI, is a way of obtaining images of organs using a magnetic field without using harmful ionizing radiation. It uses a magnnetic field so there are some contraindications peculiar to magnetic field like metallic implants, cardiac pacemakers, cochlear implants etc. There is no risk of because of radiaition and is a non-invasive safe procedure.
It is especially useful for evaluation of Brain and spinal cord. It has advantages of being able to take images in all three planes that is multiplanar imaging.It is also an alternative to CT in patients who are allergic to iodine as contrast material used in MRI is Gadolinium, which is a paramagnetic substance. It has very high soft tissue contrast so has revolutionized soft tissue and musculoskeletal imaging.
It takes a longer time to do a MRI and it is a tunnel like structure so patients with claustrophobia (fear of closed places) may have trouble getting a MRI done.

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Welcome to the information site for patients

Have you ever as a patient felt the need to know the meaning of all the technical terms that your doctor seems to say all the time!!!

Have you ever wondered what does a MRI/CT/IVPetc mean or what to except in the procedure??

Or do you want to know about the adverse effects of a procedure or Contraindiactions??

Then this is the site for you!!!

All are welcome to this site... please feel free to express your opinion, queries, doubts and clarifications here!!!