The
application of laser to surgical practice is a
constantly evolving chapter in medical procedures.
Laser is the short form of Light Amplification
by The Stimulated Emission of Radiation. This concept
is a part of quantum electronics popularly known
as laser physics, which was established by Albert
Einstein. Einstein worked upon Neil Bohr’s
model of the atom and postulated the theory of
the stimulated emission of radiation, which led
to the development of the laser.
If we elaborate on the concept of the laser,
it could be defined as electromagnetic radiation
of any wavelength (light) made larger and more
powerfully active (amplification and stimulation)
and sent out (emission) as transmitted energy
in the form of waves (radiation). The process
can be explained as a condition when photons
of light get excited, produce more photons and
are released as laser energy in the form of a
beam or ray.
However, it was much later in 1954 that the
prospective of laser technology was identified.
The process was triggered off by two scientists
of Bell Laboratories, Arthur L Schawlow and Charles
H Townes. They came up with groundbreaking ideas
about laser activity, which they got published
in a scientific journal in 1958 and simultaneously
applied for a patent. Their work was acknowledged
worldwide. Townes went on the get the Nobel Prize
in Science in 1964, which he however shared with
Alexander Prochorov, who had developed the same
theory in Moscow.
There was a third researcher in the same field,
who however failed to get befitting credit for
his work. It was Gordon Gould, a researcher at
Columbia University, New York. Though he developed
upon the same concept that won acclaim for Schawlow
and Townes, he could not publicize it in time
and filed his patent nine months after the duo.
Though he got credit for introducing the term “laser,” he
had to fight a long battle before his work was
acknowledged.
Laser technology next got an impetus in 1960,
when physicist Theodore H. Maiman, invented the
first working surgical laser. It was a flashlamp-driven
ruby laser, producing millisecond pulses of 694
nm of red light. This marked the beginning of
implementing laser technology for surgical purposes.
Thereafter various new forms of lasers and their
application followed. Here is an overview of
the different types.
Ruby laser
After Maiman’s invention, scientists at
Bell Laboratories introduced the ruby laser as
a surgical device. The flash lamp was later substituted
with an arc lamp. This ensured that the laser
could be continuously functional. The first application
of the ruby laser was in the rectification of
retinal hemorrhages. This happened after ophthalmologists
documented that the wavelength of the ruby laser
could pass through the light tissue of the eye
with negligible consequences. They also found
that it was also effectively absorbed in the
dark red tissue of the retina. However, later
the argon laser was preferred over the ruby laser
for retinal surgery.
Helium-Neon (HENE) laser
Ali Javan, a scientist at Bell Laboratories,
is credited for the development of the helium-neon
(HeNe) laser in 1960. With its discovery, laser
wavelength could be delivered in a continuous
mode. The HeNe gas laser revolutionized telecommunications.
In 1960, right after the first functional HeNe
laser went into action; Bell Laboratories’ scientists
used laser technology to transmit a telephone
conversation. Since then laser telecommunication
through fiber optics has been indispensable to
the cell phone, computer and television technology.
In the medical sector HeNe laser is used by
surgeons to visualize invisible lasers such as
carbon dioxide (CO2), holmium and yttrium aluminum
garnet (YAG) wavelengths. The HeNe laser is also
used in laser pointers and laser light shows.
Carbon dioxide (CO2) laser
This was the first invisible laser and was invented
in 1964 by Kumar Patel, yet another Bell Laboratories’ scientist.
This laser functioned in a CO2 medium. In 1972,
the CO2 laser became applicable to laser surgery,
when it was customized to work with the functional
microscope. Since then CO2 laser has proved to
have an edge over other laser wavelengths and
soon became the mainstay of laser surgical procedures.
Neodymium YAG (ND:YAG), argon and potassium
titanyl phosphate (KTP) laser
The year 1964 saw the development of two new
lasers, the neodymium YAG (Nd:YAC) laser and
the argon laser. In 1981 came the potassium titanyl
phosphate (KTP) laser. Holomium, excimer and
tunable dye wavelengths are the latest developments
in laser technology.
Laser treatments
Laproscopic surgery or minimally invasive surgery
with laser technology was the first major development
in clinical laser treatment between 1989 and
1992. It was first implemented in biliary disease.
However,
it remains
a cost
prohibitive option and hence not the first choice
in most surgical cases.
However, with all the many laser developments,
laser surgery has become a reality in various
medical fields.
Regardless of the specific laser use in the clinic
for different conditions, lasers operate with
almost the same basic technology. Indeed, not
much has changed in the basic design and laser
technology with which
they
started
off, with
the additions of computerized and stable functions
and more sophisticated surgical techniques.
Lasers became more easy to use after 1992, with
state-of-the-art control mechanisms. All this
and much more have been milestones in the advancement
in medical technology and laser has become one
of the most sophisticated choices in surgical
techniques.