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

well as prognostic tools.

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