Radio pill and endoscope.

1. RADIO PILL & ENDOSCOPE

2. Radio pill
• A capsule containing a miniature radio transmitter
that can be swallowed by a patient.
• During its passage through the digestive tract it
transmits information about internal conditions
(acidity, etc.) that can be monitored by means of a
radio receiver near the patient.
• Such capsules can contain video cameras and light
sources to examine the bowel.

3. • Radio pill is pressure-sensing endoradiosonde
• less than 1 cm' in volume so that it can be swallowed by the
patient
• As it travels through the gastrointestinal tract, it measures
the various pressures it encounters.
• Similar devices have also been built to sense temperature,
pH, enzyme activity, and oxygen tension values by the use of
different sensors or transducers.
• Pressure is sensed by a variable inductance,
• temperature is sensed by a temperature-sensitive transducer

5. pressure-sensitive endoradiosonde(radiopill)
• Hartley oscillator with constant amplitude of oscillation and
variable frequency is used to communicate the information.
• The ferrite core of the coil is attached to a diaphragm
• The diaphragm causes the coil to move in and out as a function of
pressure and, varies the value of inductance in the coil.
• This change in inductance produces a corresponding change in the
frequency of oscillations.
• Inward motion of the ferrite core produces a decrease in
frequency. Thus, changes in pressure modulate the frequency.
• radio-frequency voltage across the emitter resistor was
transmitted by a an antenna or resonator coil acts as an antenna.
• The transmitted frequencies(100 kHz to 100 MHz), can be picked
up on any simple receiver

6. Radio pill(pressure-sensitive endoradiosonde)

7. • Design requirements
1.size as small as possible(length 3cm, dia-1cm)
2. Need for Replaceable battery
3. Transmission limited to maximum of 50hrs
4. Linear response to pressure variation
5. High sensitivity
6. Temperature stability-output inductance independent of temperature
variation
7. Non responsive diaphragm to body fluids
8. Flexible design(includes provision for temp, pH etc measurement)

8. Endoscope(Fibroscope)
-tubular optical instrument to inspect internal body cavities which are
not visible
- Endoscope are made up of large diameter short wavelength low
quality silica fibers-fibroscope
- The fibers are flexible or rigid
• endoscopes consists of two fiber bundles
- one is to illuminate the internal structure of the body
-other is to collect reflected light from the internal structure of the body
-LED or LASER is used as light source and photodiode as detector. Laser
is preferable than LED
• Body cavities can be inspected either through existing orifice in the
body or passage created with sharp instrument
• During inspection body cavity is filled with air or isotonic saline to
keep the walls distended and to improve optical transmission

9. • The fiber consists of central core with high refractive index n1,
which is surrounded by a cladding made up of lower refractive
index n2
• The light is guides through the glass fiber by total internal
reflection
• The numerical aperture(light collection efficiency) of fiber=(n1-
n2)1/2
• For wider view and better image quality, telescope system is
added in the internal part of the endoscope

12. Endoscopic Laser coagulator
-Argon ion laser is useful in coagulation of blood vessels since laser
light is absorbed by RBC or hemoglobin
-Absorption of argon ion laser results in photo coagulation of blood
protein and micro hemostasis.
-This method is used in photocoagulation of retina because of its
smaller diameter and ability to do coagulation without affecting
the adjacent healthy tissue
-To control gastric hemorrhage photo coagulation is used
-Flexible fiber allow the laser beam to move in any direction