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The History of Bronchoscopy in Japan: The Keynote Lecture at 12th WCB & WCBE, June 18, 2002, Boston

Shirakawa, Taeko MD

History

The history of Japanese bronchology started in 1907. Within the broad stream of 95 years until today's flourishing art, many pioneers have contributed to promote further development in this field. Indeed, Japan has been taking a very important role to lead world bronchology. In this article, I focus especially on 3 key persons at each historical turning point.

From the Pulmonary Division of Internal Medicine, National Saishunso Hospital, Kumamoto, Japan.

Reprints: Taeko Shirakawa, MD, Pulmonary Division of Internal Medicine, National Saishunso Hospital 2659, Suya, Nishigoshi-machi, Kikuchi-gun, Kumamoto, Japan; (e-mail: shirakawa@vega.ocn.ne.jp).

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INOKICHI KUBO (1874–1939)—THE FIRST BRONCHOSCOPIST IN JAPAN

The first person is Inokichi Kubo (Fig. 1), the first Japanese bronchoscopist who opened the door of Japanese bronchology. Inokichi Kubo, known as “Ino Kubo,” was born December 26, 1874, in a small village in Fukushima prefecture. The boy Ino was very diligent, willingly helped with housework and nursing his small brother and sister.

FIGURE 1.

FIGURE 1.

At the age of 16, he started school life in Tokyo. It was enjoyable; however, his financial situation was extremely difficult. Meantime, he began to write “Tanka Poems,” a still popular special kind of Japanese poem of 31 syllables. Soon he became recognized as one of the most excellent Tanka poets. 1

In 1900, Kubo graduated from Tokyo University Medical School at the age of 26 and began working as an otorhinolaryngologist at Tokyo University. The specialty was very new and was represented at only a few institutions. He worked not only as chief of the ENT department, but also as an editor of the journal. In the evening, he gave lectures to a private study group on ENT. All of his coworkers respected him very much as an exceptionally hardworking person. However, no one ever heard him complaining “I am busy” or “I am tired.”2

In 1903, Ino Kubo was awarded a grant by the Japanese government to go to Germany. 3 So first he went to Freiburg, which had become the “Mecca of bronchoscopy” as a result of Killian's high reputation. Hundreds of physicians came from all over the world. Kubo soon became “Killian's most faithful student” because of his intelligence and amiable personality. Working at Freiburg University, he acquired the most advanced knowledge and techniques of the time. 4,5

When he left Freiburg, Killian presented him an inkpot as a memento. 6 Not only did he pack this inkpot but, of course, he did not forget to pack some Killian-type bronchoscopes into his suitcase. These are the instruments that opened the new field of Japanese medicine.

In January 1907, he returned to Japan to become professor of otorhinolaryngology at Fukuoka University (presently Kyushu University) (Fig. 2). 3 Eight months later, in September 1907, he performed the first bronchoscopy in Japan. Using the Killian-type bronchoscope, he succeeded to remove a foreign body (a drum tack) from the left main bronchus of a 14-year-old boy. 7 In those times, the common method for removing a foreign body from the airway was to irritate the airway with a feather through a tracheotomy. Therefore, the bronchoscopic method, which did not require tracheotomy, really left the audience astonished. 8,9 Some criticized the method as dangerous. However, the bronchoscopic method was very efficient for retrieval of foreign bodies; more than 2000 foreign bodies were removed from the airways as well as from the esophagus using the endoscope in the ENT department of Kyushu University during his service. 10

FIGURE 2.

FIGURE 2.

Furthermore, Kubo explored the frontiers of this field and established new methods one after the other:Figure 3 shows the successful treatment of life-threatening compression of the trachea by a tuberculous gravitation abscess in spinal caries (Fig. 3). The endoscopic incision and drainage of the peritracheoesophageal abscess saved the 17-year-old boy's life. Kubo's first steps as the Japanese pioneer of bronchoscopy were exceptionally great. 1

FIGURE 3.

FIGURE 3.

Until his retirement, he continued to be the leader who established modern bronchoesophagology and otorhinolaryngology in Japan. His memory is preserved in the Kubo Museum at Kyushu University, Fukuoka. 6,11

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JO ONO (1898–1989)—THE PIONEER OF BRONCHOESOPHAGOLOGY IN JAPAN

In 1934, the year of Kubo's retirement, a new leader appeared. Jo Ono (Fig. 4) came back to Japan from the United States with Jackson-type bronchoscopes. 12 He is the second key person who contributed greatly to the extensive spread of bronchology in Japan.

FIGURE 4.

FIGURE 4.

Jo Ono was born in 1898, the year after Killian's first bronchoscopy, in Fukushima prefecture, coincidentally the same place as Ino Kubo. At the age of 16, he went to the United States. He studied medicine at Lafayette University and Jefferson University in Pennsylvania and obtained an MD degree. 12

In 1932, Ono started to study bronchoesophagology under Chevalier Jackson. Chevalier Jackson is very famous as the person who established modern bronchoesophagology in the United States. 13

When Jo Ono came back to Japan with the Jackson-type bronchoesophagoscope in 1934, only the Killian-type and Brünings-type were available. Shinichi Chiba had already introduced Brünings-type scopes to Japan in 1910. The Jackson-type scope with a small lamp at its tip made everybody astonished. 9

In 1949, he was invited to Keio University as a visiting professor. In those days, shortly after World War II, Japan was extremely poor. As a result of a shortage of food and housing, tuberculosis was raging all through Japan. Therefore, antituberculosis plans had to be carried out urgently. In this situation, for correct diagnosis of tuberculosis and the decision for a surgical procedure, the importance of bronchoscopy had become recognized.

Therefore, Ono began to hold training courses (Fig. 5). Before that, bronchoscopy was mainly a procedure for retrieval of foreign bodies that otorhinolaryngologists performed. However, now the surgeons and internists began to obtain knowledge and master the technique of bronchoscopy for the treatment of tuberculosis. Starting in 1949, during 15 years, Ono held 51 courses. The number of participants from all over Japan counted 1169. Thus, he contributed greatly to the spread of bronchoscopy throughout Japan. 12,14

FIGURE 5.

FIGURE 5.

In the procedure of rigid bronchoscopy, the assistant plays a very important role in holding the patient's head. During the courses, Ono was always a very enthusiastic teacher and tried to show all the procedures to every 20 to 30 participants. Therefore, it took a very long time. The assistant had to keep holding the patient's head against the paresthetic feeling in his arms. 15 So, in his mind, he might be shouting to Dr. Ono, “Doctor! Oh, no!”

Several participants of the first course recognized the necessity for a professional organization. Therefore, in the same year, the Japanese Society for Bronchoesophagology was established, and Ono was elected as the first president.

In 1958, the 7th WCBE was held in Kyoto. Only 7 years later, the 11th WCBE was held in Hakone. Both meetings were successful not only for their scientific level, but also for the friendly relationships among bronchoesophagologists from all over the world. 12

Besides science, the Japanese Society for Bronchoesophagology took a very important role in the field of social activities. In those days, pencil caps were frequent airway foreign bodies. The society made a petition to change the design with holes at the tip to avoid airway obstruction. Therefore, all the plastic caps produced after the 1960s have holes (Fig. 6). Furthermore, they succeeded in prohibiting the production and sale of dangerous toys that could cause suffocation, against strong opposition by toy companies. 12,14 How many children's lives have been saved by these activities?

FIGURE 6.

FIGURE 6.

In the1960s, bronchology was developing with increasing speed before the next great innovation. In 1962, Ono had to make a movie presentation on esophagoscopy during a congress. For that purpose, Ono asked Shigeto Ikeda to produce a film on that technique. Ikeda developed an esophagotelescope using glass fibers as a light guide and made the film on esophagoscopy. When Ono presented this movie at the congress, the audience praised its very clear image. 16

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SHIGETO IKEDA (1925–2001)

Shigeto Ikeda (Fig. 7) is the person who developed the bronchofiberscope and caused a revolution in bronchology.

FIGURE 7.

FIGURE 7.

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Childhood and Youth

Shigeto Ikeda was born on July 1, 1925, in Tokyo. His father Tsunesaburo was a practitioner. Since childhood, he was very inquisitive, especially about machinery and very much interested in cameras and 8-mm movies.

In the summer of his 23rd year, when Ikeda was a medical student in Keio University, he fell ill of tuberculous pleurisy. However, he decided never to give up and overcame tuberculosis to become a doctor treating patients experiencing the same disease. Indeed, he overcame several hardships such as absence from school for a few months for treatment, his father's sudden death, and surgical procedures. Finally, he became a thoracic surgeon himself and worked on the tuberculosis ward. He made his dream become realized.

In those days, bronchography was an important method for diagnosis and deciding on the indications of surgery in tuberculosis. Ikeda began bronchography as his own work, performing 50 cases in a week, 2000 cases per year. For 10 years, he did no less than 20,000 procedures of bronchography. One day, when he was so eagerly taking movies of bronchography, he suddenly fell ill from irradiation exposure and had to be urgently hospitalized. 16

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Development of the Bronchofiberscope

In 1962, Ikeda moved to the National Cancer Center, founded a few months previously. The President, Shichiro Ishikawa, recognized Ikeda's talent and potential, which was what this newly established institute needed. Here, with Eitaka Tsuboi, he began diagnosis for lung cancer, using the Tsuboi-type curette. At the same time, he was performing rigid bronchoscopy. However, with rigid scopes, the observation range was restricted. Furthermore, under local anesthesia, it caused considerable discomfort to the patient.

“Is there any good method to observe the deeper part of bronchus that does not torture the patient?”

The development of a new method was the earnest desire of many other pulmonologists and thoracic surgeons.

In those days, many people were trying to apply glass fiber technology for medical uses. In 1962, Ikeda, with Kenichi Takino and Shohei Horie, succeeded in applying glass fibers to the rigid scope for brighter illumination instead of the small lamp. In the same year, Ikeda developed the previously mentioned device to extend a glass fiber bundle to connect with a more powerful light source. Soon after, he developed a similar type of bronchoscope and named it the “rigid-type bronchoscopic telescope.”

Then, he got an idea to develop the flexible bronchoscope using glass fibers also for imaging. If this idea could be realized, it would be obvious that not only the patient's discomfort could be reduced, but also diagnosis would become more certain.

“Nothing but the development of this scope must be my duty.”

Ikeda was firmly convinced of that. It would be just a dream considering the level of those days' technology. However, for a scientist, dreams are the source of creation. In Ikeda's mind, the image of the ideal bronchoscope was becoming clearer and clearer.

Early in 1964, Ikeda asked Haruhiko Machida of the Machida Endoscope Company to produce the flexible bronchofiberscope. Ikeda indicated 9 requirements for the bronchofiberscope: outer diameter less than 6 mm, image guide fiber less than 15 μ, more than 15,000 in a bundle, and so on.

“Oh, my God!”

Machida shouted, “Do I have to satisfy all of these requirements?”

Everything seemed the most difficult that Machida had ever experienced. In fact, it was far more difficult work for Machida than he had expected. After many series of trials and errors for more than 2 years, it was on July 23, 1966, that Machida finally visited Ikeda with the first model (Fig. 8). The first bronchofiber scope in the world was born! Ikeda's hands were slightly trembling with excitement.

FIGURE 8.

FIGURE 8.

It was only 3 weeks before the 9th World Congress on Diseases of Chest in Copenhagen, Denmark. Therefore, using this scope, Ikeda immediately made a 16-mm movie titled “The Development of the Bronchofiberscope” and flew to Copenhagen. After oral and film presentation, Ikeda took the actual scope out of his pocket and showed it to the audience.

“This is the bronchofiberscope that I have developed.”

Just at that moment, people rushed toward the stage to look at it closely. The chairman was embarrassed with this confusion.

“Dr. Ikeda, would you please go out and show it in the lobby? We still have several presentations to be continued.”

So, Ikeda went out. However, half of the audience followed him to the lobby with great excitement. After that, when he was walking in the congress hall, many doctors frequently asked him, “Are you Dr. Ikeda? Would you please show me your flexible bronchofiberscope?”16,17

However, this first model had several problems. After some improvement, he could finally get a sufficient tool in July 1967 for clinical applications, with U-turn angulation and an inside channel for biopsy forceps and anesthetic agent administration. This scope could come onto the market.

On the other hand, the Olympus Company succeeded to develop the first practical scope to be commercialized.

In September 1968, the National Institutes of Health invited Ikeda to the United States. At Johns Hopkins University in Baltimore, he gave a lecture on the bronchofiberscope and showed a film. In October, he gave the same lecture at the 10th Annual Meeting of the International Thoracic Society in Washington, DC. On the film they watched the bronchofiberscope going into the bronchi deeper and deeper where they had never seen before; all of the audience became so excited that they clapped their hands and stomped their feet.

In 1970, he was invited to the Mayo Clinic in Rochester, Minnesota, to teach the practical applications of the bronchofiberscopy to the doctors there (Fig. 9). The main reason of the invitation was to apply the bronchofiberscope to the “Mayo Lung Project,” the evaluation of the effectiveness of mass screening for lung cancer. Thus, Ikeda's invention spread all over the world and brought a revolution to medicine and bronchology. 16

FIGURE 9.

FIGURE 9.

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Ikeda's Contribution

In the 1970s in Japan, according to the increase in lung cancer, the relation between smoking and lung cancer was frequently talked about in the mass media. Ikeda, having been stimulated by the Mayo Lung Project, keenly realized the necessity of early detection and mass screening. So, supported by a grant from the Ministry of Health and Welfare Japan, “the first Ikeda research group” was organized in 1972 for the diagnosis of hilar-type early lung cancer. They started accumulating data on 100 cases of hilar-type early lung cancer. According to their analysis, they concluded that hilar-type early lung cancer could be effectively detected in the patients with cough or bloody sputum by 3-day pooled sputum cytology, and its localization could be determined by the bronchofiberscope. “The second Ikeda research group” mainly discussed the early detection of peripheral small nodular-type lung cancer, and “the third Ikeda research group” studied effective mass screening systems. As a result of these 15 years' investigation, the Japanese detection system for early lung cancer was established: chest x-ray for peripheral type, and sputum cytology for the high-risk group for hilar-type early lung cancer. This work was promoted by Tsuguo Naruke and Masahiro Kaneko. In the 1990s, in several areas in Japan, the effectiveness of this type of mass screening system has proved the statistical significance. 18

In 1975, the “Anti-lung Cancer Association of Tokyo” was organized. This is a fee-charging membership screening system for over-40-year-old, heavy-smoking men. The members were examined by chest x-ray twice a year and 3-day pooled sputum cytology. After helical computed tomography was introduced in 1993, because very small nodules are easily detected, the rate of the detection of stage Ia lung cancer has been raised from 49% to 83%. 19

Because the bronchofiberscope made the observation of smaller bronchi more easily, the former nomenclature of the tracheobronchial tree became inconvenient. Therefore, Ikeda established his well-known new practical nomenclature.

Ikeda also became a visiting professor of Kitasato University, where he held a regular conference. Furthermore, he continued to provide study courses for the practitioners in Kanagawa prefecture. At first, to understand the basic 3-dimensional anatomy of the lung, all the participants made wire models of the tracheobronchial tree. By this method, their x-ray reading ability was greatly improved. 16

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Establishment of the Societies

In those days, the bronchofiberscope had already spread widely all over Japan. Study meetings were frequently held independently in various places by enthusiastic young investigators. In the Tokyo area, the “Kanto Study Group for Bronchology” was organized in 1974. In the same year, the “Kinki Group” also started their activity. Ikeda felt the necessity to standardize bronchology. So, he asked Shigeki Hitomi to have a joint meeting in Osaka. In April 1978, the first meeting of the “Japanese Study Group for Bronchology” was held. This was held with the collaboration of the “Kinki” and “Kanto” groups. Two hundred bronchoscopists from all over Japan attended this first joint meeting and discussed very enthusiastically. The study groups in various areas were organized as branches. Since then, this meeting was held once a year and 5 years later, it was reestablished as the “Japan Society for Bronchology.”

In July 1978, the first “World Congress on Bronchoscopy” was held in Tokyo (Fig. 10). Six hundred sixty bronchoscopists from 26 countries gathered together. In the next year, 1979, the “World Association for Bronchology” was established. Its office was placed in Tokyo, and Ikeda was elected president.

FIGURE 10.

FIGURE 10.

Ikeda not only developed the instrument, but also devoted his energy to national and international societies for bronchologists to facilitate further study. 9,16,20

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Development of the Video Bronchoscope

From 1983, Ikeda with Ryosuke Ono, started to develop the video bronchoscope equipped with a Charge Coupled Device (CCD) camera at the tip. The first type was successfully produced in 1987 with Asahi Pentax. This has been called the third revolution in bronchology. The video bronchoscope was also produced by other companies, and from the 1990s explosively prevailed to become the main device today. 9,16

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The Last Years

However, in 1979, the first cerebral infarction attacked Ikeda, followed by repeated myocardial infarctions as well as cerebral infarctions. Nevertheless, he was not defeated but continued to fight against the disease with his spirit of “Never give up.” His wife Taeko supported him devotedly. In recent years, in the wheelchair operated by his wife, he continued to encourage his pupils at the congress, which he himself had established.

On December 25, 2001, he finally died. Acute myocardial infarction suddenly took away his life. “The great star has fallen.” At his funeral, hundreds of callers, flowers, and telegrams of condolence from all over the world showed how great his achievements were and how many friends he had. Once again, I would like to express my deep condolences to Dr. Ikeda's family.

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Recent Years

Many doctors followed Ikeda and have been studying frontier fields of bronchology. Takashi Arai proved that transbronchial lung biopsy using a bronchofiberscope is a very effective method. In addition, he developed the ring-arm fluoroscope. 21 Harubumi Kato developed photodynamic therapy and opened the possibility of curative treatment of hilar-type early lung cancer by an endoscopic approach. 22 Recently, an ultrathin bronchoscope, 2.8 mm in outer diameter, has been developed. This scope can reach to adjacent sites to peripheral coin lesions. For intractable pneumothorax, bronchial embolization with Endobronchial Watanake Spigot (EWS), developed by Yoichi Watanabe, is the most recent effective method. 23 At the same time, new technologies by foreign doctors have always been stimulating further development of Japanese bronchology, like autofluorescence bronchoscopy developed by Stephen Lam or endobronchial ultrasonography by Heinrich D. Becker. Noriaki Kurimoto compared Endobronchial Ultrasonography (EBUS) image and postoperative pathology and proved that EBUS was the most effective method of evaluation for tumor invasion to the bronchial wall. 24

On the other hand, as a result of the increase in lung cancer, we frequently see patients with malignant airway stenosis or bleeding. As a result of the necessity of stenting or laser treatment, people again recognized the usefulness of the rigid bronchoscope. Therefore, in 1998 in Hiroshima, the 21st annual congress of the Japan Society for Bronchology was held under the main theme of “Interventional Bronchoscopy,” inviting Dumon and other European pioneers. Teruomi Miyazawa, who contributed to open the new era of Japanese bronchology with the combination of rigid and flexible bronchoscopes, arranged this.

Finally, in June 2000, the 11th WCB & WCBE was held in Yokohama (presidents Hirokuni Yoshimura and Akinori Kida), where 796 members from 33 countries all over the world met under the motto of “the State of the Art in the Digital Age.”

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EPILOGUE

Early in the 20th century, Gustav Killian in Germany taught Ino Kubo who opened the door to Japanese bronchology. A quarter of a century later, after learning under Chevalier Jackson in the United States, Jo Ono promoted the widespread use of bronchoscopy all over Japan. Next, Shigeto Ikeda in Japan became the leader of world bronchology. Recently in bronchology, international cooperation has been established. In this new century, borders are irrelevant. Reflecting the history of bronchology in Japan, we are proud that we inherited the great works of many forerunners. Therefore, holding up Ikeda's motto “Never Give Up,” all of us should be torch runners, going hand in hand with bronchoscopists all over the world, to move ahead for further progress. This should be our duty at the beginning of the new 21st century.

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ACKNOWLEDGMENTS

The author is greatly indebted to the generous support of the following: Dr. Shigeto Ikeda and Mrs. Taeko Ikeda, Drs. Hirokuni Yoshimura, Masaaki Ohata, Harubumi Kato, Takashi Arai, Sotaro Komiyama (ENT Department of Kyushu University), Toyoji Soda, Akihiro Shiotani (ENT Department of Keio University), Takayuki Shirakusa, Heinrich D. Becker, Etsuo Kinuwaki, Hiroshi Kikuchi, Takaichiro Suzuki, Yoichi Watanabe, Teruomi Miyazawa, Yuka Miyazu, Koichi Yamashita, Akira Koyama, Takao Takizawa, J. Patrick Barron, Mr. Tatsuo Maeda (WAB), Tetsuya Fukushima (Studio Cockpit), Atsushi Ogino (Tokyo Anti-Lung Cancer Society), Motoyoshi Tauchi, Ms. Mutsumi Koketsu (Japan Bronchoesophagological Society), and Ms. Miyoko Machida.

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6. The Department of Otorhinolaryngology, Faculty of Medicine, Kyushu University. Inventory of Kubo Museum, 1985.
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13. Ono J. The Biography of Virtuous Chevalier Jackson, the Pioneer of Broncho-esophagology. Tokyo: Insatsukyoku Choyokai, 1973.
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20. Oho K, Okitsu H. The first decade of the Japan Society for Bronchology. Journal of Japan Society for Bronchology. 1988; 9:300–311.
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22. Hayata Y, Kato H, Konaka C, et al. Hematoporphyrin derivative and laser photoradiation in the treatment of lung cancer. Chest. 1982; 81:269–276.
23. Watanabe Y, Matsuo K, Tamaoki A, et al. Bronchial embolization using an endobronchial Watanabe spigot for intractable pneumothorax and bronchial fistula. Journal of Japan Society for Bronchology. 2001; 23:510–515.
24. Kurimoto N, Murayama M, Yoshioka S, et al. Assessment of usefulness of endobronchial ultrasonography in determination of tracheobronchial tumor invasion. Chest. 1999; 115:1500–1506.
Keywords:

history; bronchoscopy; Japan; Ino Kubo; Jo Ono; Shigeto Ikeda

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