Various means of diagnosis are available.
1. Most important: Clinical laboratory tests which include
any tissue or fluid obtained from the body.
2. Imaging sciences: X-rays, ultrasound, color Doppler,
computerized axial tomography (CAT) scan, magnetic
resonance imaging (MRI) scan and the latest positron
emission tomography (PET) scan.
3. Electrical signal processing techniques: ECG, EMG, EEG
and nerve transmission techniques, etc.
4. Direct visualization techniques: With the availability
of fiberoptic-based technologies, the clinician is
now capable of passing small tubes (called scopes)
through natural passage ways of the human body
(without actually surgically opening up the part),
e.g. gastroscopy, cystoscopy, etc. These techniques,
eventually culminate in taking small tissue samples
(biopsies) which are sent to histopathology laboratories.
So, whenever, any sample from a human body is taken
(either voided naturally or obtained by the clinician or the
laboratorian), it is referred to the clinical laboratory for
investigation. On receipt of a report from the laboratorian,
the clinician, then, makes up his mind and starts a
unidirectional or specific treatment against the disease
thus diagnosed. It would not be wrong to designate medical
laboratory personnel as the backbone of the clinicians. But,
for these technologists, the clinicians would forever grope
in the dark. Gone are the days when diabetes mellitus was
presented with the classical triad of symptoms—increased
thirst, hunger and urination; likewise, typhoid seldom
presents with a step-ladder pattern fever. Blood testing
is absolutely mandatory, to know that they exist, their
severity and eventually, after treatment; to know that they
are under control or cured. Investigations are diagnostic as
