Endoscope

"Endo-" is a scientific Latin prefix derived from Ancient Greek ἐνδο- (endo-) meaning "within", and "-scope" comes from the modern Latin "-scopium", from the Greek σκοπεῖν (skopein) meaning to "look at" or "to examine".{{cite web |title=endoscope |url=https://www.oed.com/view/Entry/61959?redirectedFrom=endoscope#eid5605957 |website=Oxford English Dictionary |publisher=Oxford Press |language=en}}

File:Bozzini's_Lichtleiter.svg

The first endoscope was developed in 1806 by German physician Philipp Bozzini with his introduction of a "Lichtleiter" (light conductor) "for the examinations of the canals and cavities of the human body".{{cite journal |last1=Bozzini |first1=Philipp |year=1806 |title=Lichtleiter, eine Erfindung zur Anschauung innerer Teile und Krankheiten, nebst der Abbildung |trans-title=Light conductor, an invention for examining internal parts and diseases, together with illustrations |url={{Google books|dn8tAAAAcAAJ|page=107|plainurl=yes}} |journal=Journal der Practischen Arzneykunde und Wundarzneykunst |language=de |volume=24 |pages=107–24}} However, the College of Physicians in Vienna disapproved of such curiosity.{{Cite book |last=Yamada |first=Tadataka |url=https://books.google.com/books?id=U6BdMMytieQC&q=first+endoscope+developed+in+1806&pg=PA884 |title=Atlas of Gastroenterology |date=2009-01-22 |publisher=John Wiley & Sons |isbn=978-1-4443-0342-1 |name-list-style=vanc}} The first effective open-tube endoscope was developed by French physician Antonin Jean Desormeaux.{{Cite web |title=Desormeaux, Antonin Jean |url=https://history.uroweb.org/biographies/desormeaux-antonin-jean/ |access-date=2022-06-29 |website=EAU European Museum of Urology |language=en-GB}} He was also the first one to use an endoscope in a successful operation.{{Cite journal |last=Janssen |first=Diederik F |date=2021-05-17 |title=Who named and built the Désormeaux endoscope? The case of unacknowledged opticians Charles and Arthur Chevalier |url=http://journals.sagepub.com/doi/10.1177/09677720211018975 |journal=Journal of Medical Biography |language=en |volume=29 |issue=3 |pages=176–179 |doi=10.1177/09677720211018975 |issn=0967-7720 |pmid=33998906 |s2cid=234747817|url-access=subscription }}

After the invention of Thomas Edison, the use of electric light was a major step in the improvement of endoscope. The first such lights were external although sufficiently capable of illumination to allow cystoscopy, hysteroscopy and sigmoidoscopy as well as examination of the nasal (and later thoracic) cavities as was being performed routinely in human patients by Sir Francis Cruise (using his own commercially available endoscope) by 1865 in the Mater Misericordiae Hospital in Dublin, Ireland.{{cite journal |vauthors=Caniggia A, Nuti R, Lore F, Martini G, Turchetti V, Righi G |date=April 1990 |title=Long-term treatment with calcitriol in postmenopausal osteoporosis |journal=Metabolism |volume=39 |issue=4 Suppl 1 |pages=43–9 |doi=10.1136/bmj.1.223.345 |jstor=25204557 |pmc=2325571 |pmid=2325571}} Later, smaller bulbs became available making internal light possible, for instance in a hysteroscope by Charles David in 1908.{{cite book |last1=Shawki |first1=Osama |url=https://books.google.com/books?id=0SYLDgAAQBAJ&pg=PA13 |title=Mastering the Techniques in Hysteroscopy |last2=Deshmukh |first2=Sushma |last3=Pacheco |first3=Luis Alonso |publisher=Jaypee Brothers Medical Publishers |year=2017 |isbn=978-93-86150-49-3 |pages=13– |name-list-style=vanc}}

Hans Christian Jacobaeus has been given credit for the first large published series of endoscopic explorations of the abdomen and the thorax with laparoscope (1912) and thoracoscope (1910){{cite journal |vauthors=Litynski GS |date=Jan–Mar 1997 |title=Laparoscopy—the early attempts: spotlighting Georg Kelling and Hans Christian Jacobaeus |journal=JSLS |volume=1 |issue=1 |pages=83–5 |pmc=3015224 |pmid=9876654}} although the first reported thoracoscopic examination in a human was also by Cruise.{{cite journal |last1=Gordon |first1=Samuel |name-list-style=vanc |year=2014 |title=Art. VIII.—Clinical reports of rare cases, occurring in the Whitworth and Hardwicke Hospitals |url=https://zenodo.org/record/1865816 |journal=Dublin Quarterly Journal of Medical Science |volume=41 |issue=1 |pages=83–99 |doi=10.1007/BF02946459}}

Laparoscope was used in the diagnosis of liver and gallbladder disease by Heinz Kalk in the 1930s.{{cite book |last1=Wildhirt |first1=Egmont |title=Neue Deutsche Biographie (NDB). Band 11 |last2=Kalk |first2=Heinrich-Otto |date=1977 |publisher=Duncker & Humblot |isbn=978-3-428-00192-7 |location=Berlin |page=60 |name-list-style=vanc}} Hope reported in 1937 on the use of laparoscopy to diagnose ectopic pregnancy.{{cite book |url=https://books.google.com/books?id=pCUgAwAAQBAJ&pg=PA131 |title=Paediatric and Adolescent Gynaecology: A Multidisciplinary Approach |vauthors=Balen AH, Creighton SM, Davies MC, MacDougall J, Stanhope R |date=2004-04-01 |publisher=Cambridge University Press |isbn=978-1-107-32018-5 |pages=131–}} In 1944, Raoul Palmer placed his patients in the Trendelenburg position after gaseous distention of the abdomen and thus was able to reliably perform gynecologic laparoscope.{{cite journal |vauthors=Litynski GS |date=Jul–Sep 1997 |title=Raoul Palmer, World War II, and transabdominal coelioscopy. Laparoscopy extends into gynecology |journal=Journal of the Society of Laparoendoscopic Surgeons |volume=1 |issue=3 |pages=289–92 |pmc=3016739 |pmid=9876691}}

Georg Wolf, a Berlin manufacturer of rigid endoscopes established in 1906, produced the Sussmann flexible gastroscope in 1911.{{cite web |title=About Richard Wolf Germany |url=https://www.richardwolfusa.com/company/100-years-of-innovation.html |publisher=Richard Wolf Medical Instruments}}{{cite web |title=Endoscope Biopsy channels|url=https://smarttechmed.com/endoscope-biopsy-channels/|publisher=Richard Wolf Medical Instruments}} Karl Storz began producing instruments for ENT specialists in 1945 through his company, Karl Storz GmbH.{{cite web |last1=Nezhat |first1=Camran |name-list-style=vanc |date=2005 |title=Chapter 19. 1960's |url=http://laparoscopy.blogs.com/endoscopyhistory/chapter_19/index.html |url-status=dead |archive-url=https://web.archive.org/web/20180727115326/http://laparoscopy.blogs.com/endoscopyhistory/chapter_19/index.html |archive-date=2018-07-27 |access-date=2016-01-07 |work=Nezhat's History of Endoscopy |publisher=Society of Laparoendoscopic Surgeons}}

File:Storz_Endoscopy_Unit.png exams of the vocal folds and the glottis]]

Basil Hirschowitz, Larry Curtiss, and Wilbur Peters invented the first fiber optic endoscope in 1957.{{cite journal |vauthors=Edmonson JM |date=March 1991 |title=History of the instruments for gastrointestinal endoscopy |journal=Gastrointestinal Endoscopy |volume=37 |issue=2 Suppl |pages=S27–56 |doi=10.1016/S0016-5107(91)70910-3 |pmid=2044933}} Earlier in the 1950s Harold Hopkins had designed a "fibroscope" consisting of a bundle of flexible glass fibres able to coherently transmit an image. This proved useful both medically and industrially, and subsequent research led to further improvements in image quality.

The previous practice of a small filament lamp on the tip of the endoscope had left the choice of either viewing in a dim red light or increasing the light output – which carried the risk of burning the inside of the patient. Alongside the advances to the optics, the ability to 'steer' the tip was developed, as well as innovations in remotely operated surgical instruments contained within the body of the endoscope itself. This was the beginning of "key-hole surgery" as we know it today.{{Cite journal |last=Sun |first=Guoging |display-authors=etal |date=January 2019 |title=Comparison of keyhole endoscopy and craniotomy for the treatment of patients with hypertensive cerebral hemorrhage |journal=Medicine |location=Baltimore |volume=98 |issue=2 |page=e14123 |doi=10.1097/MD.0000000000014123 |pmc=6336657 |pmid=30633227 |doi-access=free}}

There were physical limits to the image quality of a fibroscope. A bundle of 50,000 fibers would only give a 50,000-pixel image, and continued flexing from use breaks fibers and progressively loses pixels. Eventually, so many are lost that the whole bundle must be replaced at a considerable expense)

. Harold Hopkins realised that any further optical improvement would require a different approach. Previous rigid endoscopes suffered from low light transmittance and poor image quality. The surgical requirement of passing surgical tools as well as the illumination system within the endoscope's tube which itself is limited in dimensions by the human body left very little room for the imaging optics.{{citation needed|date=July 2022}} The tiny lenses of a conventional system required supporting rings that would obscure the bulk of the lens' area. They were also hard to manufacture and assemble and optically nearly useless.{{citation needed|date=July 2022}}

The elegant solution that Hopkins invented was to fill the air-spaces between the 'little lenses' with rods of glass. These rods fitted exactly the endoscope's tube making them self-aligning and requiring of no other support.{{citation needed|date=July 2022}} They were much easier to handle and utilised the maximum possible diameter available.

With the appropriate curvature and coatings to the rod ends and optimal choices of glass-types, all calculated and specified by Hopkins, the image quality was transformed even with tubes of only 1mm in diameter. With a high quality 'telescope' of such small diameter the tools and illumination system could be comfortably housed within an outer tube. Once again, it was Karl Storz who produced the first of these new endoscopes as part of a long and productive partnership between the two men.{{cite web |title=History |url=http://www.haroldhopkins.org/history.html |work=Harold Hopkins Society}}

Whilst there are regions of the body that will always require flexible endoscopes (principally the gastrointestinal tract), the rigid rod-lens endoscopes have such exceptional performance that they are still the preferred instrument and have enabled modern key-hole surgery.{{citation needed|date=July 2022}} (Harold Hopkins was recognized and honoured for his advancement of medical-optic by the medical community worldwide. It formed a major part of the citation when he was awarded the Rumford Medal by the Royal Society in 1984.)

File:Insertion_tip_of_endoscope.jpg

A typical endoscope is composed of following parts:

• A rigid or flexible tube as a body.
• A light transmission system that illuminates the object to be inspected. For the light source, it is usually located outside the scope body.
• A lens system that transmits the image from the objective lens to the observer, usually a relay lens system in the case of a rigid endoscope or a bundle of optical fibers in the case of a fiberoptic endoscope.
• An eyepiece which transmits the image to the screen in order to capture it. However, modern videoscopes require no eyepiece.
• An additional channel for medical instruments or manipulators (only for a multi-function endoscope, see below in "Classification").

Besides, patients undergoing endoscopy procedure may be offered sedation in order to avoid discomfort.

File:Laparoscopic stomach surgery.jpg

File:Endoscopy_room.jpg

Endoscopes may be used to investigate symptoms in the digestive system including nausea, vomiting, abdominal pain, difficulty swallowing, and gastrointestinal bleeding.{{cite web |author=Staff |year=2012 |title=Upper endoscopy |url=http://www.mayoclinic.com/health/endoscopy/MY00138/METHOD=print |access-date=24 September 2012 |work=Mayo Clinic}} It is also used in diagnosis, most commonly by performing a biopsy to check for conditions such as anemia, bleeding, inflammation, and cancers of the digestive system. The procedure may also be used for treatment such as cauterization of a bleeding vessel, widening a narrow esophagus, clipping off a polyp or removing a foreign object.

Health care workers can use endoscopes to review the following body parts:

• The gastrointestinal tract:
• Esophagus: chronic esophagitis, esophageal varices, esophageal hiatal hernia, esophageal leiomyoma, esophageal cancer, cardiac cancer, etc.
• Stomach and duodenum: chronic gastritis, gastric ulcer, benign gastric tumor, gastric cancer, duodenal ulcer, duodenal tumor.
• Small intestine: small intestine neoplasms, smooth muscle tumors, sarcomas, polyps, lymphomas, inflammation, etc.
• Large intestine: nonspecific ulcerative colitis, Crohn's disease, chronic colitis, colonic polyps, colorectal cancer, etc.
• The pancreas and biliary tract:
• pancreatic cancer, cholangitis, cholangiocarcinoma, etc.
• The laparoscopy:
• liver disease, biliary disease, etc.
• The respiratory tract:
• lung cancer, transbronchoscopy lung biopsy, selective bronchography, etc.
• The urinary tract:
• cystitis, bladder conjugation, bladder tumor, renal tuberculosis, renal stones, renal tumors, congenital malformations of ureter, ureteral stones, ureteral tumors, etc.
• The ear, nose and throat:
• Ear: tympanitis, inner ear deformity, etc.
• Nose: rhinitis, nasal polyp, etc.
• Throat: retropharyngeal abscess, specific infection, etc.

File:Rigid_endoscope.jpg

File:PENTAX Colonoscope001.jpg

There are many different types of endoscopes for medical examination, so are their classification methods. Generally speaking, the following three classifications are more common:

• According to functions of the endoscope:
• single-function endoscope: A single-function endoscope refers to an observation mirror that only has an optical system with it.
• multi-function endoscope: For a multi-functional endoscope, in addition to the function of observation, it also has at least one working channel like lighting, surgery, flushing and other functions.
• According to detection areas reached by the endoscope:
• enteroscope
• otoscope
• colonoscope
• rhinoscope
• arthroscope
• laparoscope
• etc.
• According to rigidity of the endoscope:
• rigid endoscope: A rigid endoscope is a prismatic optical system with advantages of clear imaging, multiple working channels and multiple viewpoints.
• flexible endoscope: A flexible endoscope is an optical-fiber-based system. Notable features of a flexible endoscope include that the lens can be manipulated by the operator to change direction, but the imaging quality is not as good as a rigid one.

Robot assisted surgery

File:CapsuleEndoscope.jpg

With the development and application of robotic systems, especially surgical robotics, remote surgery has been introduced, in which the surgeon could be at a site far away from the patient. The first remote surgery was called the Lindbergh Operation.{{Cite web |date=2007-10-13 |title=cooltech.iafrica.com {{!}} tech news World first transatlantic robotic surgery |url=http://cooltech.iafrica.com/technews/807264.htm |access-date=2022-06-30 |archive-url=https://web.archive.org/web/20071013094649/http://cooltech.iafrica.com/technews/807264.htm |archive-date=2007-10-13 }} And a wireless oesophageal pH measuring devices can now be placed endoscopically, to record ph trends in an area remotely.{{Cite web |title=Esophageal pH Test: MedlinePlus Medical Test |url=https://medlineplus.gov/lab-tests/esophageal-ph-test/ |access-date=2022-06-30 |website=medlineplus.gov |language=en}}

Endoscopy VR simulators

Virtual reality simulators are being developed for training doctors on various endoscopy skills.{{cite web |title=Overview of Endoscopy Haptics Simulator Project |url=https://www.youtube.com/watch?v=ogMr5u5oqN8 |work=M2D2 Laboratory, Indian Institute of Science |publisher=YouTube}}

Disposable endoscopy

Disposable endoscopy is an emerging category of endoscopic instruments. Recent developments{{cite web |title=Dokument nicht gefunden |url=http://www.fraunhofer.de/en/press/research-news/2010-2011/15/cameras-out-of-the-salt-shaker.jsp |url-status=dead |archive-url=https://web.archive.org/web/20110720064520/http://www.fraunhofer.de/en/press/research-news/2010-2011/15/cameras-out-of-the-salt-shaker.jsp |archive-date=2011-07-20}} have allowed the manufacture of endoscopes inexpensive enough to be used on a single patient only. It is meeting a growing demand to lessen the risk of cross contamination and hospital acquired diseases. A European consortium of the SME is working on the DUET (disposable use of endoscopy tool) project to build a disposable endoscope.{{cite web |date=2018-03-26 |title=Development of a Disposable Use Endoscopy Tool |url=http://www.ist-world.org/ProjectDetails.aspx?ProjectId=6ad6814768374801b7401a5ae435dec6 |url-status=dead |archive-url=https://web.archive.org/web/20110723225345/http://www.ist-world.org/ProjectDetails.aspx?ProjectId=6ad6814768374801b7401a5ae435dec6 |archive-date=2011-07-23}}

Capsule endoscopy

Capsule endoscopes are pill-sized imaging devices that are swallowed by a patient and then record images of the gastrointestinal tract as they pass through naturally. Images are typically retrieved via wireless data transfer to an external receiver.{{Cite web |title=Patient Information |url=https://www.asge.org/home/for-patients/patient-information |access-date=2022-07-01 |website=asge.org |language=en}}

Augmented reality

The endoscopic images can be combined with other image sources to provide the surgeon with additional information. For instance, the position of an anatomical structure or tumor might be shown in the endoscopic video.{{YouTube|i4emmCcBb4s|Augmented Reality: Path guidance to craniopharyngioma}}

Image enhancement

Emerging endoscope technologies measure additional properties of light such as optical polarization,{{cite journal |vauthors=Manhas S, Vizet J, Deby S, Vanel JC, Boito P, Verdier M, De Martino A, Pagnoux D |date=February 2015 |title=Demonstration of full 4×4 Mueller polarimetry through an optical fiber for endoscopic applications |journal=Optics Express |volume=23 |issue=3 |pages=3047–54 |bibcode=2015OExpr..23.3047M |doi=10.1364/OE.23.003047 |pmid=25836165 |doi-access=free}} optical phase,{{cite journal |last1=Gordon |first1=GSD |last2=Joseph |first2=J |last3=Alcolea |first3=MP |last4=Sawyer |first4=T |last5=Macfaden |first5=AJ |last6=Williams |first6=C |last7=Fitzpatrick |first7=CRM |last8=Jones |first8=PH |last9=di Pietro |first9=M |last10=Fitzgerald |first10=RC |last11=Wilkinson |first11=TD |year=2018 |title=Quantitative phase and polarisation endoscopy applied to detection of early oesophageal tumourigenesis |journal=Journal of Biomedical Optics |volume=24 |issue=12 |pages=1–13 |arxiv=1811.03977 |doi=10.1117/1.JBO.24.12.126004 |pmc=7006047 |pmid=31840442 |first12=SE |last12=Bohndiek}} and additional wavelengths of light to improve contrast.{{cite journal |vauthors=Kester RT, Bedard N, Gao L, Tkaczyk TS |date=May 2011 |title=Real-time snapshot hyperspectral imaging endoscope |journal=Journal of Biomedical Optics |volume=16 |issue=5 |pages=056005–056005–12 |bibcode=2011JBO....16e6005K |doi=10.1117/1.3574756 |pmc=3107836 |pmid=21639573}}

File:Endoscope,_USB,_2015-05-30.jpg

Industrial endoscopic nondestructive testing technology

The above is mainly about the application of endoscopes in medical inspection. In fact, endoscopes are also widely used in industrial field, especially in non-destructive testing and hole exploration. If internal visual inspection of pipes, boilers, cylinders, motors, reactors, heat exchangers, turbines, and other products with narrow, inaccessible cavities and/or channels is to be performed, then the endoscope is an important, if not an indispensable instrument.{{Cite web |title=Nondestructive Testing: Endoscopy :: Total Materia Article |url=https://www.totalmateria.com/page.aspx?ID=CheckArticle&site=kts&NM=188 |access-date=2022-07-02 |website=www.totalmateria.com}} In such applications they are commonly known as borescopes.

• Medical device
• Endoscopy
• Surgery
• Anesthesia
• Minimally invasive procedure
• Robot assisted surgery

{{Reflist}}

Category:Endoscopes

Category:Medical devices