The document describes the history and development of endoscopy from its origins with Bozzini's "Lichtleiter" in 1806 to modern innovations. Key developments include: - Desormeaux introducing Bozzini's device into patients and coining the term "endoscope" in 1853. - Czerny constructing the first rigid endoscope in 1880 and using Edison's light bulb, allowing angling and air insufflation. - Kelling pioneering laparoscopy in 1901 after being introduced to endoscopy by Mikulicz-Radecki. - Hopkins inventing the rigid rod-lens system for scopes in 1959, allowing their widespread adoption after partnering with

2. Bozzini’s “Lichtleiter”
The “Lichtleiter” was made from an
aluminum tube. The tube was illuminated
by a wax candle and had mirrors fitted to
it in order to reflect the images.
Bozzini published his invention in 1806 in
the Hufeland’s Journal of Practical
Medicine, Volume 24, under the title
“Light Conductor, An Invention for the
Viewing of Internal Parts and Diseases
with Illustration.”
Incidentally, Bozzini was censured for
“undue curiosity” by the Medical Faculty
of Vienna for this invention. (Courtesy of
Olympus Austria,

3. Antoine Jean Desormeaux
Antoine Jean Desormeaux (1815–1894), a French
Surgeon, was the first to introduce the Bozzini’s
“Lichtleiter” into a patient. In 1853, he further
developed the Lichtleiter and termed his device
the “Endoscope.” It was the first time this term
was used in history.
Desormeaux presented the endoscope in 1865 to
the Academy in Paris. He even used his endoscope
to examine the stomach; but due to an insufficient
light source he was not quite successful.
(Copyright Verger-Kuhnke AB. The life of Philipp
Bozzini (1773-1809), an idealist of endoscopy. Actas
Urol Esp. 2007;31:437-444)

4. Desormeaux’s “Endoscope”
Desormeaux’s endoscope used as a light source a
kerosene lamp Berning alcohol and turpentine,
with a chimney to enhance the flame and a lens to
condense the beam to a narrower area to achieve a
brighter spot.
He used this instrument to examine the urethra
and bladder.
As might have been expected, burns were the
major complication of these procedures.
Interestingly, he thought of using electricity but
felt it unsafe.
(Courtesy of Olympus Austria, Vienna, Austria)

5. Johannes Freiherr
surgeon of Polish-Lithuanian descent born in
Bukowina, Romania, constructed the first rigid
endoscope in 1880 and was the first to use
Edison’s light bulb for his gastroscope in
practice.
He modified the instrument so that it could be
angled by 30Åã near to its lower third to
achieve better visualization.
He added a separate channel for air
insufflation. In one of the first interventional
endoscopic procedures, he pushed a large
swallowed bone from the esophagus into the
stomach, thus avoiding surgery. (Copyright:
surgeon in the evolution of flexible endoscopy.
Surg
Endosc 2007: 21; 838-853 Springer Verlag)

6. Georg Kelling (1866–1945), a German
physician
from Dresden, was introduced to
endoscopy and gastrointestinal surgery
when he worked with Professor Mikulicz-
Radecki at the Royal Surgical Clinic in
Breslau, Germany. In with the help of
Nitze’s cystoscope, and coined this
laparoscopic examination “celioscopy.”
He used air filtered through sterile cotton
to create pneumoperitoneum in dogs. For
insufflation he used a trocar Developed by
Alfred Fiedler, an internist from Dresden.
(Copyright: Hatzinger M: Georg Kelling
(1866–1945) Der Erfinder der modernen
Laparoskopie. Urologe A 2006; 45 (7):868-71
Springer Verlag)

7. Harold Horace Hopkins
Hopkins (1918–1994) obtained a degree in physics and
mathematics at Leicester University in 1939. After the war,
in 1947, Hopkins became a research fellow at Imperial
College, London, UK.
Hopkins invented the rigid rod-lens system for scopes,
which allows double light transmission, requires short and
thin spacer tubes, and gives a larger and clearer aperture.
He filed a patent for the rod-lens system in 1959.
However, the English and American companies to whom he
offered the system displayed little interest.
The situation changed however in 1965 when Professor
George Berci, who recognized the potential of this
invention, introduced Hopkins to Karl Storz to manufacture
the scopes. (Courtesy of William P. Didusch Center for
Urologic History, American Urological Association, MD,
USA)

8. Kurt Karl Stephan Semm
Kurt Karl Stephan Semm (1927–2003) was born in Munich,
Germany, where he also studied medicine at the Ludwigs-
Maximillian University. In 1958, he wrote his medical
thesis under the guidance of Nobelmlaureate Adolf
Butenandt. Semm began his career in gynecology under
Professor Fikentscher in Munich. In 1970s, as the Head of
Gynecology in Kiel, introduced an;
1- Automatic insufflation device capable of monitoring
intra-abdominal pressures,
2- Endoscopic loop sutures,
3-Extra- and intracorporeal suturing techniques.
4-Created the pelvi- trainer. He performed the first
laparoscopic appendectomy
in 1982. (Courtesy of Monika Bals-Pratsch MD,
Zentrum für Gyn.kologie, Universit.t Regensburg,
Germany)

9. Anatomy of a Rigid Scope

10.  Central to the instrumentation is the scope. Its
backbone is the rod lens system designed by
Hopkins.
 The shaft of scopes houses both light fibers
 and viewing optics.
 The viewing optic consist of three distinct
parts:
o The objective lens,
o Rod lenses,
o ocular lens.

11. Field of View
The field of view (also field of vision)
is the angular extent of the
observable area that is seen at any
given moment. The field of view in
scopes for endoscopic surgery can
vary from 600 to 820 depending up
on the type of instrument. Wider
angles of view provide a greater
depth of field in the image with
better utilization of illumination. A
smaller field of view allows the
scope to be farther from the tissue,
for the same to be observed.

12. Angle of View
The angle of view in scopes can vary with
respect to the central axis view are
designated as 00 and provide a straight
view of the structure in question. Scopes
are also available with a 50, 250, 300, 450,
and even 700 angle of view, allowing
utilization of the scopes much as a
periscope. The off-axis scopes enable one
to observe
down into the gutters and up the anterior
abdominal wall as well as sideways. Off-axis
scopes are difficult to work with; however,
they provide an excellent means of
obtaining close inspection of tissues
at difficult angles and positions.

13. Scope Size and Screen Image
The decrease in the size of scopes was an important
factor in the advancement of minimally invasive
surgery in the pediatric age group. Although scopes
are available in sizes from 1.9 mm to 12 mm in
diameter, the majority of the procedures are
performed using 5- or 10-mm scopes.
When compared to the reduced view obtained in the
previous generation of scopes (left), modern5-mm,
full-screen scopes provide a bright, distortion- free,
full-screen image (right). In addition, the image size
in modern 5-mm scope is equivalent to that obtained
by the previous-generation
10-mm scope. (Courtesy of Richard Wolf, Knittlingen,
Germany)

14. Charge Coupled Device (CCD)
Video Cameras Scope cameras are available in either
single-chip
three-chip versions (one chip offers 300,000 pixels/cm2).
In single-chip CCD cameras, all the three primary colors (red,
blue and green) are sensed by a single chip. In three-chip CCD
cameras, there are three chips for separate capture and
processing of the primary colors.
Single-chip CCD cameras produce images of 450 lines/inch
resolution and are ideal for outpatient surgery. On the other
hand, three-chip CCD cameras have high fidelity with
unprecedented color reproduction to produce images of 750
lines/ inch resolution that can be viewed optimally on flat-panel
screens and are best suited for endoscopic surgery.
(Courtesy of RichardWolf, Knittlingen , Germany)
Light source:
Light-Source Generators and Transmission Pathways There
are two commonly utilized light sources: halogen and xenon.
A schematic overview of light transmission is outlined12

15. The Concept of White Balancing
White balancing should be performed before
inserting the camera inside the abdominal cavity. This
is necessary before commencing surgery to diminish
the added impurities of color that may be introduced
due to a variety of reasons such as:
(1) voltage difference,
(2) staining of the tip by cleaners,
(3) scratches and wear of the eyepiece.
White balancing is achieved by keeping a white
object in front of the scope and activating the
appropriate button on the video system or camera.
The camera senses the white object as its reference
to adjust all of the primary colors (red, blueand
green). (Courtesy of Richard Wolf, Knittlingen,
Germany)

17. A three-CCD camera is a camera whose
imaging system uses three separate charge-coupled
devices (CCDs),
each one taking a separate measurement of
the primary colors, red, green, or blue light.
Light coming into the lens is split by a
trichroic prism assembly, which directs the
appropriate wavelength ranges of light to
their respective CCDs.
The system is employed by still cameras,
telecine systems, professional video cameras
and some prosumer video cameras.

18. Rods and Cones
The retina contains two types of photoreceptors,
Rods
cones.
The rods are more numerous, some 120 million, and are more sensitive than the
cones
they are not sensitive to color. The 6 to 7 million cones provide the eye's color
sensitivity and they are much more concentrated in the central yellow spot known as
the macula. In the center of that region is the " fovea centralis ", a 0.3 mm diameter
rod-free area with very thin, densely packed cones.
The experimental evidence suggests that among the cones there are three different
types of color reception. Response curves for the three types of cones have been
determined. Since the perception of color depends on the firing of these three types
of nerve cells, it follows that visible color can be mapped in terms of three
numbers called tristimulus values.
Color perception has been successfully modeled in terms of tristimulus values and
mapped on the CIE chromaticity diagram.

19. Rods Do Not See Red!
The light response of the rods peaks sharply in the blue; they respond very little
to red light. This leads to some interesting phenomena:
Red rose at twilight: In bright light, the color-sensitive cones are predominant
and we see a brilliant red rose with somewhat more subdued green leaves. But
at twilight, the less-sensitive cones begin to shut down for the night, and most
of the vision comes from the rods. The rods pick up the green from the leaves
much more strongly than the red from the petals, so the green leaves become
brighter than the red petals!
The ship captain has red instrument lights. Since the rods do not respond to red,
the captain can gain full dark-adapted vision with the rods with which to watch
for icebergs and other obstacles outside. It would be undesirable to examine
anything with white light even for a moment, because the attainment of
optimum night-vision may take up to a half-hour. Red lights do not spoil it.
These phenomena arise from the nature of the rod-dominated dark-adapted
vision, called scotopic vision.

20. Cone Details
Current understanding is that the 6 to 7 million cones can be divided
into "red" cones (64%), "green" cones (32%), and "blue" cones (2%)
based on measured response curves. They provide the eye's color
sensitivity. The green and red cones are concentrated in the fovea
centralis . The "blue" cones have the highest sensitivity and are
mostly found outside the fovea, leading to some distinctions in the
eye's blue perception.
The cones are less sensitive to light than the rods, as shown a typical
day-night comparison. The daylight vision (cone vision) adapts much
more rapidly to changing light levels, adjusting to a change like
coming indoors out of sunlight in a few seconds. Like all neurons, the
cones fire to produce an electrical impulse on the nerve fiber and
then must reset to fire again. The light adaption is thought to occur
by adjusting this reset time.
The cones are responsible for all high resolution vision. The eye
moves continually to keep the light from the object of interest falling
on the fovea centralis where the bulk of the cones reside.

22. The combination of the three sensors can be done in the
following ways:
Composite sampling, where the three sensors are perfectly
aligned to avoid any color artifact when recombining the
information from the three color planes
Pixel shifting, where the three sensors are shifted by a fraction
of a pixel. After recombining the information from the three
sensors, higher spatial resolution can be achieved.
Pixel shifting can be horizontal only to provide higher
horizontal resolution in standard resolution camera, or
horizontal and vertical to provide high resolution image using
standard resolution imager for example. The alignment of the
three sensors can be achieved by micro mechanical
movements of the sensors relative to each other.
Arbitrary alignment, where the random alignment errors due
to the optics are comparable to or larger than the pixel size.

23. Compared to cameras with only one CCD, three-CCD cameras
generally provide superior image quality through enhanced
resolution and lower noise.
By taking separate readings of red, green, and blue values for each
pixel,
three-CCD cameras achieve much better precision than single-CCD
cameras.
By contrast, almost all single-CCD cameras use a Bayer filter, which
allows them to detect only one-third of the color information for
each pixel.
The other two-thirds must be interpolated with a demosaicing
algorithm to 'fill in the gaps', resulting in a much lower effective
resolution

24. Video and Data Storage
Equipment
2.21.1 Digital Video Recorders
Modern endoscopic surgery towers are generally
equipped with digital video disc (DVD) recorders
(DVRs), which enable recording of a procedure
in digital quality. The procedures are recorded on
commercially available DVDs, which can later be
viewed on normal DVD players or edited on personal
computers.
DVRs have evolved into devices that are feature
rich and provide services that exceed the simple
recording of video images that was previously
achieved using video cassette recorders (VCRs).
DVR systems provide a multitude of advanced
functions,
including video searches by event and time.

25. Digital Video Printers
A variety of printers from small print
format to
large A5 print format are available.
These printers
offer high-resolution prints, quick, 20-s
print time,
and high-quality, curl-free prints at 400
dpi resolution.
Most modern printers come with a
four-frame
memory. The new compact design of
printers allows
for easy integration with other video
equipment.
Small, compact printers are ideal for
the office
setting, but large-print format printers
are preferable
in the operating room.

26. Digital Video Managers
These are computer-based systems that
display intuitive
patient information screens that allow for
quick and easy input of vital data. The data is
stored
on hard drives and can be viewed as images
or
videos, and may be stored or deleted. The
editing
screen enables viewing and editing
procedures.
Current systems allow storage of up to 50
patient
archives for multiple procedures. These
systems
are compatible with personal computers and
hospital network software. (Courtesy of
Richard
Wolf, Knittlingen, Germany)

27. Tracking Instruments using Color
Markers
Place colored marker on instrument
Convert RGB to HSV space
Hue value of a pixel is much less susceptible to lighting changes
Record hue value of marker to be tracked
Search entire image for hue values within epsilon range
Centroid of matched pixels gives position of tracker in the image
If target is detected, localize search to a smaller neighborhood
Tracking performed in real-time at 25 fps

28.  Allows shared autonomy with surgeon
 The feedback from the tracker can be used to drive motors to
keep the tool in the center of the image
 PD controller used
 ( Ex , Ey ): off set error of tracker from center of image
Pan speed  ( x * Ex ) – ( x * dEx/dt )
Tilt speed  ( y * Ey ) – ( y * dEy/dt )

29. Stereo image

30. 3D Trajectory Reconstruction
 The Flock of Birds (FoB) sensor can
transmit the position of its sensor w.r.t.
its base
 Accuracy within 1.8mm
 Refresh rate up to 144Hz
By placing an optical marker on the FoB
sensor we can track its position in the
image
 By tracking the sensor using stereo
cameras we can compute its 3D
trajectory

31. Stereo Camera

32. 3D Displays
eMagin Z800 Head-Mounted VR Display
- Uncomfortable
- Single User
RealD Crystal Eyes shutter glasses
- Uncomfortable over longer periods
- Need to maintain Line Of Sight with
synchronizing emitter
True Vision back projected 3D display
- Low incremental cost for additional users
- Bigger display size
-Passive polarization, lightweight glasses