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– detecting condition abnormalities: heart blocks and bundle branch
blocks (BBB)
– screening for ischaemic heart disease during an exercise tolerance
test, often carried out on an exercise bike or treadmill
Providing information on the physical condition of the heart, for
example in patients with left ventricular hypertrophy (LVH)
– detecting electrolyte disturbances, for example low plasma potas-
sium levels.
c) An ophthalmoscope allows the doctor to examine all parts of
the eye: the iris, lens, retina and optic disc. For best results, the exam-
ination is done with dimmed, or lowered, lights to allow the pupil to
maximally dilate or widen. A topical mydriatic solution may be ap-
plied to the eye to aid dilation. Then the doctor asks the patient to fix-
ate on a target for the duration of the test.
2.
Analysis of body fluids
such as blood, urine, and spinal and
brain fluid. These procedures may provide major clues or confor-
mation of a suspected disease.
During venipuncture, the phlebotomist, a technician who takes
blood, inserts a needle into a vein and withdraws blood into a speci-
men tube, which is sent to the haematology laboratory for analysis.
Usually the phlebotomist can find a vein in the inner part of elbow, the
antecubital fossa, that is easily accessible. She may apply a tourniquet
(a tight band) above the site, or she may order the patient to clench
hand to make a fist, in order to make the vein more prominent. After-
wards, if the patient wants the blood to clot and swelling and a haema-
toma (a black and blue mark, or a bruise) to be prevented, he may be
asked to press lightly on a dressing, usually a piece of gauze, where
the vein was punctured.
3.
Imaging
, which generally involves getting pictures of what is
going on inside the body. X-rays are considered to be the most com-
mon, but others include ultrasound, radioisotope scans, computed to-
mography (CT) scans, magnetic resonance imaging (MRI), and posi-
tron emission tomography (PET) scans.
a)
Radiography
involves exposing a part of the body to a
small dose of radiation to produce an imagine of the internal or-
gans. Organs with high density such as ribs and spine are radio-