Electronic endoscopy of the gastrointestinal tract. Initial experience with a new type of endoscope that has no fiberoptic bundle for imaging

In vivo laser speckle contrast imaging of microvascular blood perfusion using a chip-on-tip camera

Laser speckle contrast imaging (LSCI) is an important non-invasive capability for real-time imaging for tissue-perfusion assessment. Yet, the size and weight of current clinical standard LSCI instrumentation restricts usage to mainly peripheral skin perfusion. Miniaturization of LSCI could enable hand-held instrumentation to image internal organ/tissue to produce accurate speckle-perfusion maps. We characterized a 1mm2 chip-on-tip camera for LSCI of blood perfusion in vivo and with a flow model. A dedicated optical setup was built to compare chip-on-tip camera to a high specification reference camera (GS3) for LSCI. We compared LSCI performance using a calibration standard and a flow phantom. Subsequently the camera assessed placenta perfusion in a small animal model. Lastly, a human study was conducted on the perfusion in fingertips of 13-volunteers. We demonstrate that the chip-on-tip camera can perform wide-field, in vivo, LSCI of tissue perfusion with the ability to measure physiological blood flow changes comparable with a standard reference camera.

Endoscopic gastric mucosal atrophy as a predictor of colorectal polyps: a large scale case-control study

Although some studies have indicated a correlation between Helicobacter pylori infection and the risk of colorectal neoplasms, these findings have not been consistent and are controversial. This case-control study aimed to investigate the association between endoscopic gastric mucosal atrophy and colorectal polyp occurrence. Records of 7,394 participants who underwent colonoscopy examinations from August 2008 to July 2018 were reviewed retrospectively. A total of 2,404 subjects were registered; 1,565 (65.1%) were in the gastric mucosal atrophy-positive group and 1,138 (47.3%) had colorectal polyps. The multivariate analysis adjusted by age, sex, smoking habits, alcohol habits, hemoglobin A1c, and systolic blood pressure indicated that patients in the gastric mucosal atrophy-positive group more frequently had colorectal polyps compared with patients in the gastric mucosal atrophy-negative group (odds ratio, 3.27; 95% confidence interval, 2.68-4.01; p<0.001). An analysis of the association between gastric mucosal atrophy degree and colorectal polyp status indicated that, compared with mild gastric mucosal atrophy, severe gastric mucosal atrophy was associated with a higher risk of proximal colon polyps (odds ratio, 1.47; 95% confidence interval, 1.05-2.07; p = 0.024) and two or more colorectal polyps (odds ratio, 1.80; 95% confidence interval, 1.30-2.49; p<0.001). In conclusion, gastric mucosal atrophy found during esophagogastroduodenoscopy may be an indication for complete colon screening.

Office-Based Treatment of Glottal Dysplasia and Papillomatosis with the 585-NM Pulsed Dye Laser and Local Anesthesia

Treatment of glottal papillomatosis and dysplasia was mirror-guided and performed in surgeons' offices in the 19th century. It migrated to the operating room in the 20th century to accommodate direct laryngoscopic surgery, which required assistants to administer anesthesia and procedural support. Presently, the primary treatment goals, which are disease regression and voice restoration or maintenance, are tempered by the morbidity of general anesthesia and potential treatment-induced vocal deterioration. In fact, general anesthesia has been appropriately considered to be an acceptable source of morbidity for the promise of a precise procedure, which usually ensures airway safety and an optimal vocal outcome. However, patients with recurrent glottal papillomatosis and keratosis with dysplasia are typically monitored with various degrees of watchful waiting until there is a subjective judgment (on the part of the patient and surgeon) that the disease is more of a liability than is the procedure to treat it. Innovations in the 585-nm pulsed dye laser delivery system have allowed for its use in the clinic with local anesthesia through the working channel of a flexible fiberoptic laryngoscope. A prospective assessment was done on 51 patients in 82 cases of recurrent glottal papillomatosis (30) and dysplasia (52). All individuals had previously undergone microlaryngoscopic management with histopathologic evaluation. Five procedures could not be completed because of impaired exposure (2) or discomfort (3). Of those patients who could be treated, there was at least a 50% disease involution in 68 of 77 cases (88%) and 25% to 50% disease regression in the remaining 9 (12%). Patient self-assessment of the voice revealed that 34 of 77 were improved, 39 were unchanged, 4 were slightly worse, and none were substantially worse. These data confirm that diseased mucosa can be normalized without resection or substantial loss of vocal function. The putative mechanisms, which vary according to the fluence (energy) delivered by the laser, are photoangiolysis of sublesional microcirculation, denaturing of epithelial basement membrane linking proteins, and cellular destruction. Furthermore, this relatively safe, effective technique allowed for treatment of many patients (in a clinic setting) in whom classic surgery-related morbidity would have often delayed intervention.

Training for advanced endoscopic procedures

Advanced endoscopy has evolved from diagnostic ERCP to an ever-increasing array of therapeutic procedures including EUS with FNA, ablative therapies, deep enteroscopy, luminal stenting, endoscopic suturing and endoscopic mucosal resection among others. As these procedures have become increasingly more complex, the risk of potential complications has also risen. Training in advanced endoscopy involves more than obtaining a minimum number of therapeutic procedures. The means of assessing a trainee's competence level and ability to practice independently continues to be a matter of debate. The use of quality indicators to measure performance levels may be beneficial as more advanced techniques and procedures become available.

A preliminary report of a disposable electrical non-fiberoptic endoscope in thoracoscopic surgery

PURPOSE

Conventional thoracoscopic surgery requires a camera connected to optic fibers and rigid rod lens to ensure the provision of adequate light and quality of real-time images in the operative field. However, the camera, the connected optic fibers and rigid rod lens are not disposable due to cost, which is a concern as regards potential contamination of patients. To decrease such contamination, we designed a disposable device of extremely low cost which we tested in thoracoscopic surgery in animals.

DESCRIPTION

A complementary metal-oxide-semiconductor is used for obtaining real-time image at a refresh rate of 30 frames per second. A circumferential light was added by a light emitting diode. We connected wires to a universal serial bus adapter, with which the device can negotiate with a computer so as to control signal retrieval and adjustment of the light as well as focus. The device was designed to be as compact as possible. The contour resembled a conventional thoracoscope, but with no optic fibers and rigid rod lens included.

EVALUATION

We used the devices to perform routine thoracoscopic surgical procedures, including wedge resection of the lung, lobectomy, esophagectomy, pericardiotomy and pleural biopsy in two 40-kg pigs under general anesthesia. The operating techniques were not altered while using this device.

CONCLUSION

This disposable, electrical non-fiberoptic endoscope has the potential to be easily and safely used in routine thoracoscopic surgery at a minimal cost. Further clinical evaluation will be required to demonstrate the utility in human patients.

Morphogenesis of a colorectal neoplasm with a type IIIS pit pattern inferred from isolated crypts

BACKGROUND

The goal of this study was to clarify morphogenetic development in colorectal neoplasms with depressions by examining isolated crypts and their pit patterns.

METHODS

Twelve colorectal neoplasms with depressions were examined endoscopically, stereomicroscopically, and histopathologically. The pit pattern was defined according to Kudo's classification. The HCl digestion method was used to isolate the crypts. For scanning electron microscopy observations of the surface structure, specimens were mounted on brass stubs, coated with gold, and then observed.

RESULTS

In isolated crypts with bifurcation extending to the middle or all the way to the lesion surface, the crypt orifice was round with a type IIIS pit pattern. In those with bifurcations extending up to the upper portion, the crypt orifice was oval with a type IIIS pit pattern. Some crypts were almost completely separated into two. The orifice diameter of a nonbifurcated crypt was 95.1 +/- 28.1 microm, whereas the diameters of crypts with bifurcations extending to the middle or the upper part were 114.7 +/- 40.8 and 208.1 +/- 71.4 microm, respectively. Thus, the orifice diameter of a crypt with the bifurcation reaching the upper part was about twice that of orifices of nonbifurcated crypts or those with bifurcations extending to the middle.

CONCLUSIONS

Our results indicate that colorectal neoplasms with depressions may enlarge by a process of crypt bifurcation in which a single crypt divides into two crypts.

The effect of Nazism on medical progress in gastroenterology: the inefficiency of evil

While Nazism is almost universally recognized as a great evil, control of science and medicine by the totalitarian Nazi state might be viewed as increasing efficiency. Scientific methods are applied to semiquantitatively analyze the effects of Nazism on medical progress in gastroenterology to document its pernicious effects, and to honor outstanding gastroenterologists persecuted or murdered by the Nazis. This is a retrospective, quasi-case-controlled study. To disprove the null hypothesis that Nazism was efficient, retarded progress in gastroenterology is demonstrated by (1) enumerating the loss to Nazi Germany from 1933 to 1944 due to violent death, incarceration, or forced exile of key researchers in gastroenterology, defined by authorship of at least one book or 10 articles in peer-reviewed journals or other outstanding scholarship; (2) demonstrating a statistically significantly greater loss in Nazi Germany than in non-Nazi (Weimar German Republic from 1921 to 1932) or anti-Nazi (democratic America from 1933 to 1944) control groups; and (3) demonstrating that each loss was directly due to Nazism (murder, incarceration, or exile due to documented threat of violence/death or revocation of medical license). Sources of error in analyzing events from 70 years ago are described. Nazi Germany and Nazi-occupied Europe gained 0 and lost 53 key gastroenterology researchers, including 32 lost due to forced exile, 11 murdered by the Nazis, 5 lost due to suicide under threat of violence, 3 in hiding from the Gestapo, and 2 for other reasons. Fifty-two of the gastroenterologists were persecuted solely because they were Jewish or of Jewish descent and one because he was a Christian anti-Nazi Polish patriot. Particularly severe losses occurred in endoscopy. The loss in Nazi Germany from 1933 to 1944 was significantly greater than that in non-Nazi Germany and Austria from 1921 to 1932 (53 versus 4; odds ratio = 25.27; 95% CI: 9.01-70.48; P < 0.0001) and was significantly greater than that in anti-Nazi America from 1933 to 1944 (53 versus 0; odds ratio > 104.0; 95% CI: 17.62-608.95; P < 0.0001). Lost physicians in Nazi Germany (with reasons for loss) included Ismar Boas, the father of modern gastroenterology (suicide after medical license revoked); Hans Popper, the father of hepatopathology (fled impending arrest); Rudolph Nissen, the father of antireflux surgery (fled after job dismissal); Rudolph Schindler, the father of semiflexible endoscopy (fled after incarceration); Heinrich Lamm, the first to experimentally demonstrate fiberoptic transmission and the first to suggest its applicability for gastroscopy (fled after medical license revoked); Hermann Strauss, a pioneer in rigid sigmoidoscopy (suicide in a concentration camp); A.A.H. van den Bergh, who discovered the van den Bergh reaction to differentiate indirect from direct bilirubin (died in hiding in Nazi-occupied Holland); and Kurt Isselbacher, subsequently the Chief of Gastroenterology at Harvard Medical School (fled in childhood after a grandfather murdered by Nazis). All four refugee physicians who were reexposed to Nazi domination, after a regime change in their country of refuge, fled again or committed suicide. The Nazi damage to German and Austrian gastroenterology was immense, e.g., 13 of 14 major international discoveries in diagnostic gastroscopy were made by Germans or Austrians before the Third Reich, versus only 1 of 8 subsequently (odds ratio = 91; 95% CI: 3.58-13,887.61; P < 0.001). Eighteen (34%) of the persecuted physicians immigrated to America, thereby contributing to the postwar flourishing of American gastroenterology, particularly gastrointestinal endoscopy. In conclusion, the Third Reich severely retarded and reversed medical progress in gastroenterology in Germany. The inefficiency of Nazism, as herein documented, is attributable to the Nazi commitment of so much human, economic, and social resources to the military to wage wars of aggression, to the secret police (Gestapo) to pursue and exterminate perceived internal enemies, and to the Party to control and regiment civil society. Most inefficient is the incarceration, exile, or murder of Germany's most trained physicians and talented researchers because of religion or race, sociological parameters that are irrelevant to productivity. Intimidation and repression stifle scientific scholarship and creativity. This work disproves the myth of the efficiency of Nazism, and like tyrannies, by the novel application of semiquantitative scientific methodology to assess causality in medical history.

Electronic Videoendoscopic Laryngostroboscopy

Color images obtained using electronic videoendoscopic laryngostroboscopy (EVLS) were presented and the utility of this technique for the diagnosis of dysphonia was discussed in this paper. Stroboscopic evaluations of laryngeal lesions were performed using a rhinolaryngeal electronic videoendoscope system employing a single-plate simultaneous color charge-coupled device (CCD) chip method. Twenty patients underwent electronic videoendoscopic laryngostroboscopy. A Karl Storz laryngostroboscope Pulsar was connected to this system and laryngeal lesions were assessed. The potentialities of laryngostroboscopy using this system were evaluated. Clear stroboscopic images were obtained in all patients. Multiple still images during vocal fold vibration were acquired using an optional function. The laryngostroboscope is not compatible with conventional systems employing a single-plate red, green, and blue (RGB) surface scanning method. However, the system used was successfully connected to a laryngostroboscope. EVLS appears to be a powerful new tool for the diagnosis of dysphonia.

The role of sigmoidoscopy and colonoscopy in the diagnosis and management of lower gastrointestinal disorders: technique, indications, and contraindications

Flexible sigmoidoscopy and colonoscopy have revolutionized the clinical management of colonic diseases. Colonoscopy has a broad range of indications, including evaluating lower GI symptoms such as lower GI bleeding, evaluating abnormal radiographic findings, and screening and surveillance for colon cancer. Colonoscopy is increasingly being used therapeutically. Patient evaluation, patient instructions, and colonic preparation before colonoscopy are essential for safe and efficient colonoscopy. Intravenous sedation reduces patient pain and anxiety during colonoscopy, but requires monitoring by pulse oximetry and automated measurements of vital signs. An experienced colonoscopist can complete colonoscopy in 90% or more of cases, using maneuvers to maintain the colonic lumen in view, straighten the colonoscope, and avoid looping during colonic intubation.

The role of esophagogastroduodenoscopy in the diagnosis and management of upper gastrointestinal disorders

Esophagogastroduodenoscopy has revolutionized the clinical management of upper gastrointestinal diseases. Millions of EGDs are performed annually in the United States for many indications, such as gastrointestinal bleeding, abdominal pain, dysphagia, or surveillance of premalignant lesions. Esophagogastroduodenoscopy is very safe, with a low risk of serious complications such as perforation, cardiopulmonary arrest, or aspiration pneumonia. It is a highly sensitive and specific diagnostic test, especially when combined with endoscopic biopsy. Esophagogastroduodenoscopy is increasingly being used therapeutically to avoid surgery. New endoscopic technology such as endosonography, endoscopic sewing, and the endoscopic videocapsule will undoubtedly extend the frontiers and increase the indications for endoscopy.

Digital image processing of laryngeal lesions by electronic videoendoscopy

OBJECTIVES

To present electronic videoendoscopy of the larynx with digital image processing and to discuss this endoscopic technique from the standpoint of diagnostic usefulness of laryngeal lesions.

STUDY DESIGN

Electronic videoendoscopic evaluation of laryngeal lesions with digital image processing.

METHODS

Seventy patients underwent electronic videoendoscopy without digital image processing and, subsequently, with the digital image processing function. Of these, 15 patients with white lesion of the vocal fold and laryngeal neoplasms were assessed in the study. Clinical assessments made before enhancement of digital image processing function were compared with those after enhancement in 15 patients.

RESULTS

Of the 15 patients observed, the clinical diagnoses of two patients were changed after enhancement. Both patients underwent endolaryngeal microsurgery with histopathological examination of the removed lesions, which confirmed the definitive diagnosis. The clinical diagnoses of both patients after enhancement were compatible with histopathological diagnoses.

CONCLUSIONS

The enhanced color images provided by this system are superior in both quality and resolution to those obtained by conventional flexible fiberoptic endoscopy with a video camera. This system should be a valuable tool for the diagnosis of laryngeal lesions.

Observations of laryngeal lesions with a rhinolarynx electronic videoendoscope system and digital image processing

Laryngeal lesions were observed with the Olympus ENF-200 rhinolarynx electronic videoendoscope attached to the Olympus EVIS-200 system, an electronic videoendoscope system of Olympus Optical Co, Ltd. The electronic videoendoscope differs from conventional flexible fiberscopes in having a small light-sensitive charge-coupled device (CCD) chip built into the tip of the endoscope portion. This model has a small CCD chip in its 5-mm-outer diameter tip, and can be introduced into the laryngeal cavity by inserting it through the nasal passages. Dynamic color images obtained by this system were very clear and provided excellent resolution. This electronic videoendoscope system could also be connected to the Olympus EVIP-230 digital image processor, which was compatible with this system. Structure enhancement and color enhancement were performed by processing images. In this paper, the ordinary images and the processed images are described and discussed from the standpoint of diagnostic usefulness.

Surgical strategy for early gastric cancer

The diagnostic and therapeutic options in early gastric cancer are reviewed. In Japan, the rate of detection of early gastric cancers has increased so that minute gastric cancers can now be identified as a result of advances in diagnostic methods. The results of histopathological staging of a large number of resected specimens have led to three surgical options based on size and depth of the primary lesion, namely classical R2 resection, radical resection with limited lymphadenectomy and endoscopic surgery.

Depressed adenoma in the large intestine. Endoscopic features

To clarify the presence of depressed adenomas in the human large intestine, a prospective study was performed from January 1986 to December 1987. During these two years, 997 colonoscopies were conducted in patients, excluding cases of familial adenomatosis coli. Of 32 small, depressed lesions biopsied, seven were depressed adenomas, demonstrating that depressed adenomas do exist in the colon and rectum, and can be detected endoscopically. Resembling a sucker, they are easily detected through inflation and deflation.

A comparative study for fiberoptic and video endoscopic determination of the extent in minimal changes of gastric mucosa using indigo dye spraying

The image resolution of fiberoptic and video endoscopy was compared in a series of patients with early gastric cancer. Eighteen patients were divided into two groups. One group of patients (n = 9) was evaluated with fiberoptic endoscopy while the second group (n = 9) was evaluated using video endoscopy. The extent of cancer invasion, with special attention to size, shape and type of the lesions, was evaluated in each patient. Attempts were also made to identify the proximal and distal limits of tumor invasion and the endoscopic and postoperative findings were compared. Endoscopic delineation of lesions was possible in more patients undergoing video endoscopy compared to fiberoptic endoscopy. Video endoscopy gave better endoscopic images for determination of the limits and of the size of cancer invasion. Indigo dye spraying enhanced the accuracy rates in both groups of patients. The results of this study suggest that video endoscopy may be more useful than fiberoptic endoscopy in the evaluation of minimal mucosal changes of the gastrointestinal tract. We believe that video endoscopy may have a useful role in the gastrointestinal endoscopy if the problem of expense, which is its main drawback, can be solved.

The electronic video endoscope: clinical experience with 1200 diagnostic and therapeutic cases in the community hospital

Gastrointestinal endoscopic examinations with the Welch-Allyn and Fujinon electronic video endoscopes were evaluated in four phases in our community hospital endoscopy unit. Resolution and clinical comparisons to fiberoptic instruments offered advantages for the electronic systems. A review of 1200 consecutive procedures for efficacy, safety, and maintenance considerations was conducted. The use of the video endoscopes as first choice for nearly all diagnostic and therapeutic procedures was more favorable than for the ongoing experience with fiberoptic instruments.

Sigmoidoscopy with flexible electronic endoscopy: a preliminary experience in Hong Kong

Eighty-two cases of electronic flexible sigmoidoscopy were performed from October 1984 to October 1985 in a rural hospital in Hong Kong. The scope is a relatively new type of flexible endoscope, which has no optical fibre bundle for imaging. The image is taken with a solid state television camera and relayed via a videoprocessor to a television monitor. The image quality and ease of handling were satisfactory. Acceptance by the endoscopy team and the patients was good. The differences in comparison with conventional fibrescopes and television systems are discussed.

Advances in gastrointestinal endoscopy and laser therapy; the way ahead

Modern flexible fibreoptics enable gastroenterologists to visualise and treat many lesions and conditions in the upper gastrointestinal tract and colon. Therapeutic endoscopy is forming a larger proportion of many unit's workload and the newer techniques to stop or prevent rebleeding are the subject of much research and development. Developments in the fields of operative endoscopy, small intestinal endoscopy, and endoscopic ultrasound are also progressing rapidly. The place of video-endoscopy is still to be established but potentially has several advantages over fibreoptic endoscopy. Laser therapy has been well established as a means of treating gastrointestinal haemorrhage from peptic ulcers, and has potential use in the treatment of angiomatous lesions. It is increasingly being used both for palliation and 'cure' of malignancy and neoplasia in the gastrointestinal tract. The use of such lasers depends upon thermal damage, but newer types of non-thermal laser therapy, using pulsed lasers, or dye lasers with prior tumour sensitisation are rapidly going to be applied to the treatment of gastrointestinal disease.