Surgical Treatment for Aspiration Following Esophageal Reconstruction --A Report of Two Cases and the Techniques Involvedm Hiromasa FUJITA,1 Minoru HIRANO,2 Teruo KAKEGAWA,1 Hideaki YAMANA1 and Shinzo TANAKA2 ABSTRACT: Severe aspiration following esophageal reconstruction is often very difficult to treat while preserving the larynx. However, we have successfully adopted a modified surgical procedure previously employed for aspiration caused by neurological diseases or head and neck cancer surgery. We report herein the use of this modified procedure against aspiration in 2 cases following esophagectomy. In the first case, a combination of cricopharyngeal myotomy, infrahyoid myotomy and laryngeal pull-up, with approximation of the ,thyroid cartilage against the hyoid bone and that of the hyoid bone against the mandible, were performed simultaneously with the primary esophagectomy. In the second case, cricopharyngeal myotomy, infrahyoid myotomy, laryngeal pull-up and infrafold silicone injection were performed three months after the primary operation. Good results were achieved in both cases. Thus, for any case at risk of aspiration after esophagectomy or for any case with severe aspiration following esophagectomy that does not respond to swallow therapy, these operative rehabilitation procedures should be performed before laryn~ectomy is considered. KEY WORDS: aspiration, cricopharyngeal myotomy, fixation of the larynx, esophagectomy without laryngectomy
INTRODUCTION
D y s p h a g i a following surgery for esophageal carcinoma is one of the most disappointing postoperative problems, and dysphagia associated with aspiration frequently takes place when the larynx is preserved and anastomosis is made near the larynx. Recurrent laryngeal nerve paralysis, which often results from the surgery, the aggravates the aspiration. To ~The First Department of Surgery, and 2theDepartment of Otolaryngology, Head and Neck Surgery, Kurume University School of Medicine, Kurume,Japan Reprint requests to: Hiromasa Fujita, MD, The First Department of Surgery, Kurume University School of Medicine. 67 Asahi-machi, Kurume, Fukuoka 830, Japan
avoid this problem, there are surgeons who prefer to remove the larynx simultaneously with the esophageal lesion. 1,~ In the field of laryngology, surgical treatment has been successfully employed for dysphagia caused by neurological disease or by surgery for head and neck cancer? -8 We are currently employing similar surgical techniques for dysphagia resulting from surgery for esophageal carcinoma with good results and this paper presents two cases in which these newly-adopted surgical treatments were successfully applied. REPORT OF CASES
Case-1 The first case was a 62 year old male with a
JAPANESEJOURNALOF SURGERY,VOL.21. No. 6 pp. 687-692, 1991
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Fujita et al.
carcinoma in the cervicothoracicjunction of the esophagus who underwent blunt esophagectomy with lymphadenectomy through a partial u p p e r m e d i a n s t e r n o t o m y and laparotomy. T h e cervical and u p p e r mediasfinal lymph nodes, particularly the nodes along the recurrent laryngeal nerves, were extensively removed. T h e esophagus was reconstructed using the stomach through a p o s t e r i o r mediastinal route a n d an esophagogastrostomy made n e a r the pharyngoesophageal junction as a safe surgical margin from the tumor. T h e abdomen was closed w i t h o u t d r a i n a g e while the s t e r n o t o m y wound was closed with wires and suction drains left in the retrosternal space. Following these procedures, cricopharyngeal myotomy, 3-6 mtranyomal myotomy) ,7 and laryngeal pull-up 5,8 were performed to prevent aspiration and dysphagia. 1) Cricopharyngeal myotomy. The cervical esophagus and pharynx were isolated from the left c o m m o n carotid artery, internal jugular vein and prevertebral tissue. T h e larynx and pharynx were then rotated to the right to expose the cricopharyngeal muscle posteriorly. A strip o f this muacle, 2 cm long and 0.5 cm wide, was resected in its posterior midline, taking care not to injure the pharyngeal mucosa (Fig. 1). 2) Infrahyoidal myotomy. T h e sterno-
yroid
Cri mu vein
Fig. 1. A schematic illustration of cricopharyngeal myotomy.
J SlUg~ vember NJoPn"
Fig. 2. A schematic illustration of intrahyoid myotomy.
Fig. 3. Connection of the thyroid cartilage to the hyoid bone. hyoid and sternothyroid muscles were transected n e a r their insertion to the hyoid bone and thyroid cartilage, respectively. The omohyoid muscles were transected n e a r the hyoid insertion (Fig. 2). 3) Laryngeal pull-up. The hyoid bone and thyroid cartilage were brought together with 1-0 nylon sutures (Surgilon| as illustrated in Fig. 3. Two transverse small skin incisions, each 3 cm in length, were made bilaterally in the mental region, 2 cm from the midline. T h e mandible was exposed and two holes drilled. Using steel wires, the hyoid bone was suspended against the mandible and the larynx pulled up against the mandible (Fig. 4). T h e sternocleidomastoid muscles were then sutured and fixed to the
Volume 21 Number 6
Surgical treatment for aspiration
Fig. 4. A schematic illustration of laryngeal pull-up. The hyoid bone is approximated against the mandible.
689
sternum and clavicles and the wound in the neck closed, leaving suction drains. Postoperative complications in this case included bilateral recurrent laryngeal nerve paralysis, stricture o f the esophagogastric anastomosis, repeated aspiration p n e u m o n i a and osteomyelitis o f the sternum. T h e patient recovered from these complications, commenced oral intake one month after the operation and was discharged six months later. For two years after the operation, his clinical course continues well except for a slight disturbance in cervical movement. The postoperative contrast esophagogram before discharge showed neither aspiration n o r stricture in the anastomosis (arrows):and the steel wires holding the hyoid borie to the mandible were clearly observed (Fig. 5). Case-2
Fig. 5. Pharyngoesophagograms five months after the operation show neither aspiration nor stricture of the anastomosis (arrows). It is clearly demonstrated in the lateral view (fight) that the larynx is pulled up to a high position, by suturing the hyoid bone and the thyroid cartilage to the mandible using wires.
690
Fujita et al.
The second case was of a 57 year old male with a carcinoma in the middle thoracic es0phagus who underwent palliative esophageet0my through a right thoracotomy. The esophagus was reconstructed using the stomach througha retrosternal route and an eSophagogastrostomy made in the neck. He developed bilateral recurrent laryngeal nerve paralysis post0peratively. He commenced the oral intake of food two weeks postoperativelyl however, this was inhibited totally by repeated aspiration pneumonia. Three months after the primary operation, weZperformeda cric0pharyngel myotomy, infrahvoid mvotomv and larv0geal pull-up under lo~al anesthesia, Since aspiration was still found with a water-drinking test just after performing these procedures, bilateral infrafold silicone injection9 and tracheal fenestration were additionally performed. He started taking regular food orally without aspiration immediately after surgery and maintained this ability until he died of recurrent cancer two months later. He had been able to speak by closing a tracheostomy with his finger during phonafion. DISCUSSION When esophageal carcinoma is not too advanced, even if it is situated in the cervix or cervicothoracic junction, the larynx is often left unresected in order to preserve phonetic function. However, in some patients whose larynx is preserved, neither the ability to take food orally or phonafion are ever achieved because of postoperative persistent aspiration. Lymphadenectomy in the neck and upper mediasfinum, and particularly dissection of the nodes along the recurrent laryngeal nerves, frequently results in laryngeal nerve paralysis. Anastomosis near the larynx a n d / o r the operative scar around the larynx and trachea can disturb the laryngeal movement, and a glottic incompetence and disturbance in laryngeal elevation can lead to severe aspiration. Approximation of the vocal folds and elevation of the larynx is
Jpn. J. Surg. November 1991
effective for preventing such aspiration. Until recently, when patients developed aspiration and showed no improvement with swallow therapy after a few months, the larynx was removed. However, we have now started to employ the surgical modalities previously used in the field of laryngology for the prevention and treatment of aspiration. In our first case, a comparable set of operative procedures were performed simultaneously with the primary; esophagectomy. Despite recurrent aspiration pneumonia having occurred in the immediate postoperative period, the ~patient obtained sufficient oral intake capability by five months postoperatively. In the second case, the surgical treatment for aspiration was secondarily performed three months after the primary operation because postoperative aspiration pneumonia was not improved by swallow therapy. Hirano et al.10 classified aspiration into three types, namely; type 1 aspiration, which occurs during the second stage of swallowing when the larynx should be elevated and closed and results from incomplete laryngeal elevation and closure; type 2 aspiration, which takes place when the larynx descends and opens after the second stage of swallowing and results from a weak propelling force a n d / o r a strong resistance at the entrance of the esophagus; and type 3 aspiration, which occurs in both phases of laryngeal rising and falling. In accordance with this classification, they proposed a surgical treatment suitable for each type of aspiration. Briefly, for type 1 aspiration, laryngeal pull-up and/or mediofixation of the paretic vocal fold was proposed, and for type 2 aspiration, cricopharyngeal myotomy a n d / o r dilatation of the esophageal stricture was proposed. A consensus has not yet been reached as to which type of aspiration occurs following esophageal reconstruction. Machimura et al.1~ reported that of 34 esophagectomy patients who were videoradiographically examined, type 1 aspiration was observed in 33 per cent, type 2 aspiration in 53 per cent, and
Volume 21 Number 6
691
Surgical treatment for aspiration
type 3 aspiration in 13 per cent. Based on these results, they p e r f o r m e d cricopharyngeal myotomy simultaneously with the esop h a g e a l c a n c e r operation. I n contrast, Mambraeus et al. 1~ described that defective relaxation o f the cricopharyngeal muscle, or type 2 aspiration, was not demonstrated but that i m p a i r m e n t in the elevation a n d closure o f the larynx, or type 1 aspiration, was cineradiographically observed in m o r e than half of 9 esophagectomized patients. We investigated the swallowing function of a series o f patients with recurrent aspiration following esophageal reconstruction using videbradiography. T h e majority of o u r patients had either type 1 or type 3 aspiration, since most h a d suffered from bilateral vocal fold paralysis and impaired laryngeal movements caused by radical cervical and mediastinal l y m p h node dissection, while they rarely had any stricture in the anastomosis. Therefore, we considered that cricopharyngeal myotomy alone could not resolve the problem but that a combination of several surgical procedures including laryngeal pullup and infrahyoidal myotomy should be p e r f o r m e d in accordance with the type of aspiration. Based o n the results of o u r videoradiographic examinations, we have successfully treated severe aspiration following esophageal reconstruction. Operative procedures such as cricopharyngeal myotomy, infrahyoid myotomy, laryngeal pull-up a n d / o r mediofixation of the vocal fold were selected according to the type a n d degree o f aspiration. We p e r f o r m e d these surgical procedures for aspiration at two different stages: (1) simultaneously with t h e primary operation and (2) secondarily after a'certain interval from the primary operation. G o o d results were obtained in both cases. Complications after these procedures were minimal, except for dyspnea following mediofixation o f the vocal folds which was mollified by tracheal fenestration without loss of phonetic function. Thus, from our clinical experience, we r e c o m m e n d a combination of the aforemen-
t i o n e d p r o c e d u r e s f o r the t r e a t m e n t o f severe aspiration following esophageal reconstruction when aspiration does not improve with training over a few months. Furthermore, for patients at high risk of developing severe aspiration postoperatively who undergo esophageal anastomosis n e a r the larynx, as in our first case, we recomm e n d a combination o f these procedures be p e r f o r m e d simultaneously with esophagectomy. (Received for publication o n J u n . 1, 1990) REFERENCES 1. Ong GB. Carcinoma of the hypopharynx and cervical oesophagus. Prog Clin Surg 1969; 3: 155-178. 2. KakegawaT, Tsuzuki T, Sasaki T. Primary pharyngogastrostomy for carcinoma of the esophagus situated in the cervicothoracic segment. Surgery 1973; 73: 226-229. 3..Kaplan S. Paralysis of deglutition, a post polio.myelitis complication treated by section of the cricopharyngeus muscle. Ann Surg 1951; 133: 572-573. 4. Hirano M. Cricopharyngeal myotomy for relief of swallowing difficulties.Jibi-inkouka (Otolaryngol) 1974; 46: 807-810. (in Japanese with English Abst.) 5. Hirano M. Surgical treatments for dynamic disorders of swallowing.Jibi-inkoukaRinsyo (Practica Otologica) 1980; 73: 1667-1670. (in Japanese) 6. Duranceau AC, Jamieson GG, Beauchamp G. The technique of cricopharyngeal myotomy.Surg Clin North Am 1983; 63: 833-839. 7. Hirano M, Shin T, Yoshida Y, MaeyamaT, Nozoe I, Yoshida T. Infrahyoid myotomy--a surgical treatment for some dysphagia and speech disorders. Nippon Jibi-inkouka Gakkai Zasshi (Jpn J Otolaryngol) 1976; 79: 988-992. (in Japanese with English Abst.) 8. Naffziger HC. Paralysis of deglutition, surgical correction. Ann Surg 1948; 128: 732-742. 9. Hirano M, Yoshida T, Ohkubo H, Kufita S: Transcutaneous infrafold injection for vocal fold paralysis. Transact Am Bronch-Esophagol Assoc 1985; 115-117. 10. Hirano M, Shin T, Yoshida T, Mihashi S, Yoshida T, Okubo H. Clinical classification of aspiration caused by dynamic disorders of swallowing. Nippon Kikan Shyokudouka Gakkai Kaiho (Jpn J Bronchoesophagol Soc)1980; 31: 285-290. (in Japanese with English Abs't.)
692
Fujita et al.
11. Machimura T, Makuuchi H, Sugihara T, So Y, Shimada H, Mizutani K, Sugano K, Sasaki T, Tajima T, Mitomi T. Analysis of the swallowing movement for dysphagia after esophageal cancer operanon with videoradiography. Nippon Geka
_ Jpn. J. Surg. November 1991
Gakkai Zasshi (Jpn J Surg Soc) 1989; 90: 286. (in Japanese) 12. Hambraeus GM, Ekberg O, Fletcher R. Pharyngeal dysfunction after total and subtotal oesophagectomy. Acta Radiol 1987; 28: 409-413.
INTRODUCTION
D y s p h a g i a following surgery for esophageal carcinoma is one of the most disappointing postoperative problems, and dysphagia associated with aspiration frequently takes place when the larynx is preserved and anastomosis is made near the larynx. Recurrent laryngeal nerve paralysis, which often results from the surgery, the aggravates the aspiration. To ~The First Department of Surgery, and 2theDepartment of Otolaryngology, Head and Neck Surgery, Kurume University School of Medicine, Kurume,Japan Reprint requests to: Hiromasa Fujita, MD, The First Department of Surgery, Kurume University School of Medicine. 67 Asahi-machi, Kurume, Fukuoka 830, Japan
avoid this problem, there are surgeons who prefer to remove the larynx simultaneously with the esophageal lesion. 1,~ In the field of laryngology, surgical treatment has been successfully employed for dysphagia caused by neurological disease or by surgery for head and neck cancer? -8 We are currently employing similar surgical techniques for dysphagia resulting from surgery for esophageal carcinoma with good results and this paper presents two cases in which these newly-adopted surgical treatments were successfully applied. REPORT OF CASES
Case-1 The first case was a 62 year old male with a
JAPANESEJOURNALOF SURGERY,VOL.21. No. 6 pp. 687-692, 1991
688
Fujita et al.
carcinoma in the cervicothoracicjunction of the esophagus who underwent blunt esophagectomy with lymphadenectomy through a partial u p p e r m e d i a n s t e r n o t o m y and laparotomy. T h e cervical and u p p e r mediasfinal lymph nodes, particularly the nodes along the recurrent laryngeal nerves, were extensively removed. T h e esophagus was reconstructed using the stomach through a p o s t e r i o r mediastinal route a n d an esophagogastrostomy made n e a r the pharyngoesophageal junction as a safe surgical margin from the tumor. T h e abdomen was closed w i t h o u t d r a i n a g e while the s t e r n o t o m y wound was closed with wires and suction drains left in the retrosternal space. Following these procedures, cricopharyngeal myotomy, 3-6 mtranyomal myotomy) ,7 and laryngeal pull-up 5,8 were performed to prevent aspiration and dysphagia. 1) Cricopharyngeal myotomy. The cervical esophagus and pharynx were isolated from the left c o m m o n carotid artery, internal jugular vein and prevertebral tissue. T h e larynx and pharynx were then rotated to the right to expose the cricopharyngeal muscle posteriorly. A strip o f this muacle, 2 cm long and 0.5 cm wide, was resected in its posterior midline, taking care not to injure the pharyngeal mucosa (Fig. 1). 2) Infrahyoidal myotomy. T h e sterno-
yroid
Cri mu vein
Fig. 1. A schematic illustration of cricopharyngeal myotomy.
J SlUg~ vember NJoPn"
Fig. 2. A schematic illustration of intrahyoid myotomy.
Fig. 3. Connection of the thyroid cartilage to the hyoid bone. hyoid and sternothyroid muscles were transected n e a r their insertion to the hyoid bone and thyroid cartilage, respectively. The omohyoid muscles were transected n e a r the hyoid insertion (Fig. 2). 3) Laryngeal pull-up. The hyoid bone and thyroid cartilage were brought together with 1-0 nylon sutures (Surgilon| as illustrated in Fig. 3. Two transverse small skin incisions, each 3 cm in length, were made bilaterally in the mental region, 2 cm from the midline. T h e mandible was exposed and two holes drilled. Using steel wires, the hyoid bone was suspended against the mandible and the larynx pulled up against the mandible (Fig. 4). T h e sternocleidomastoid muscles were then sutured and fixed to the
Volume 21 Number 6
Surgical treatment for aspiration
Fig. 4. A schematic illustration of laryngeal pull-up. The hyoid bone is approximated against the mandible.
689
sternum and clavicles and the wound in the neck closed, leaving suction drains. Postoperative complications in this case included bilateral recurrent laryngeal nerve paralysis, stricture o f the esophagogastric anastomosis, repeated aspiration p n e u m o n i a and osteomyelitis o f the sternum. T h e patient recovered from these complications, commenced oral intake one month after the operation and was discharged six months later. For two years after the operation, his clinical course continues well except for a slight disturbance in cervical movement. The postoperative contrast esophagogram before discharge showed neither aspiration n o r stricture in the anastomosis (arrows):and the steel wires holding the hyoid borie to the mandible were clearly observed (Fig. 5). Case-2
Fig. 5. Pharyngoesophagograms five months after the operation show neither aspiration nor stricture of the anastomosis (arrows). It is clearly demonstrated in the lateral view (fight) that the larynx is pulled up to a high position, by suturing the hyoid bone and the thyroid cartilage to the mandible using wires.
690
Fujita et al.
The second case was of a 57 year old male with a carcinoma in the middle thoracic es0phagus who underwent palliative esophageet0my through a right thoracotomy. The esophagus was reconstructed using the stomach througha retrosternal route and an eSophagogastrostomy made in the neck. He developed bilateral recurrent laryngeal nerve paralysis post0peratively. He commenced the oral intake of food two weeks postoperativelyl however, this was inhibited totally by repeated aspiration pneumonia. Three months after the primary operation, weZperformeda cric0pharyngel myotomy, infrahvoid mvotomv and larv0geal pull-up under lo~al anesthesia, Since aspiration was still found with a water-drinking test just after performing these procedures, bilateral infrafold silicone injection9 and tracheal fenestration were additionally performed. He started taking regular food orally without aspiration immediately after surgery and maintained this ability until he died of recurrent cancer two months later. He had been able to speak by closing a tracheostomy with his finger during phonafion. DISCUSSION When esophageal carcinoma is not too advanced, even if it is situated in the cervix or cervicothoracic junction, the larynx is often left unresected in order to preserve phonetic function. However, in some patients whose larynx is preserved, neither the ability to take food orally or phonafion are ever achieved because of postoperative persistent aspiration. Lymphadenectomy in the neck and upper mediasfinum, and particularly dissection of the nodes along the recurrent laryngeal nerves, frequently results in laryngeal nerve paralysis. Anastomosis near the larynx a n d / o r the operative scar around the larynx and trachea can disturb the laryngeal movement, and a glottic incompetence and disturbance in laryngeal elevation can lead to severe aspiration. Approximation of the vocal folds and elevation of the larynx is
Jpn. J. Surg. November 1991
effective for preventing such aspiration. Until recently, when patients developed aspiration and showed no improvement with swallow therapy after a few months, the larynx was removed. However, we have now started to employ the surgical modalities previously used in the field of laryngology for the prevention and treatment of aspiration. In our first case, a comparable set of operative procedures were performed simultaneously with the primary; esophagectomy. Despite recurrent aspiration pneumonia having occurred in the immediate postoperative period, the ~patient obtained sufficient oral intake capability by five months postoperatively. In the second case, the surgical treatment for aspiration was secondarily performed three months after the primary operation because postoperative aspiration pneumonia was not improved by swallow therapy. Hirano et al.10 classified aspiration into three types, namely; type 1 aspiration, which occurs during the second stage of swallowing when the larynx should be elevated and closed and results from incomplete laryngeal elevation and closure; type 2 aspiration, which takes place when the larynx descends and opens after the second stage of swallowing and results from a weak propelling force a n d / o r a strong resistance at the entrance of the esophagus; and type 3 aspiration, which occurs in both phases of laryngeal rising and falling. In accordance with this classification, they proposed a surgical treatment suitable for each type of aspiration. Briefly, for type 1 aspiration, laryngeal pull-up and/or mediofixation of the paretic vocal fold was proposed, and for type 2 aspiration, cricopharyngeal myotomy a n d / o r dilatation of the esophageal stricture was proposed. A consensus has not yet been reached as to which type of aspiration occurs following esophageal reconstruction. Machimura et al.1~ reported that of 34 esophagectomy patients who were videoradiographically examined, type 1 aspiration was observed in 33 per cent, type 2 aspiration in 53 per cent, and
Volume 21 Number 6
691
Surgical treatment for aspiration
type 3 aspiration in 13 per cent. Based on these results, they p e r f o r m e d cricopharyngeal myotomy simultaneously with the esop h a g e a l c a n c e r operation. I n contrast, Mambraeus et al. 1~ described that defective relaxation o f the cricopharyngeal muscle, or type 2 aspiration, was not demonstrated but that i m p a i r m e n t in the elevation a n d closure o f the larynx, or type 1 aspiration, was cineradiographically observed in m o r e than half of 9 esophagectomized patients. We investigated the swallowing function of a series o f patients with recurrent aspiration following esophageal reconstruction using videbradiography. T h e majority of o u r patients had either type 1 or type 3 aspiration, since most h a d suffered from bilateral vocal fold paralysis and impaired laryngeal movements caused by radical cervical and mediastinal l y m p h node dissection, while they rarely had any stricture in the anastomosis. Therefore, we considered that cricopharyngeal myotomy alone could not resolve the problem but that a combination of several surgical procedures including laryngeal pullup and infrahyoidal myotomy should be p e r f o r m e d in accordance with the type of aspiration. Based o n the results of o u r videoradiographic examinations, we have successfully treated severe aspiration following esophageal reconstruction. Operative procedures such as cricopharyngeal myotomy, infrahyoid myotomy, laryngeal pull-up a n d / o r mediofixation of the vocal fold were selected according to the type a n d degree o f aspiration. We p e r f o r m e d these surgical procedures for aspiration at two different stages: (1) simultaneously with t h e primary operation and (2) secondarily after a'certain interval from the primary operation. G o o d results were obtained in both cases. Complications after these procedures were minimal, except for dyspnea following mediofixation o f the vocal folds which was mollified by tracheal fenestration without loss of phonetic function. Thus, from our clinical experience, we r e c o m m e n d a combination of the aforemen-
t i o n e d p r o c e d u r e s f o r the t r e a t m e n t o f severe aspiration following esophageal reconstruction when aspiration does not improve with training over a few months. Furthermore, for patients at high risk of developing severe aspiration postoperatively who undergo esophageal anastomosis n e a r the larynx, as in our first case, we recomm e n d a combination o f these procedures be p e r f o r m e d simultaneously with esophagectomy. (Received for publication o n J u n . 1, 1990) REFERENCES 1. Ong GB. Carcinoma of the hypopharynx and cervical oesophagus. Prog Clin Surg 1969; 3: 155-178. 2. KakegawaT, Tsuzuki T, Sasaki T. Primary pharyngogastrostomy for carcinoma of the esophagus situated in the cervicothoracic segment. Surgery 1973; 73: 226-229. 3..Kaplan S. Paralysis of deglutition, a post polio.myelitis complication treated by section of the cricopharyngeus muscle. Ann Surg 1951; 133: 572-573. 4. Hirano M. Cricopharyngeal myotomy for relief of swallowing difficulties.Jibi-inkouka (Otolaryngol) 1974; 46: 807-810. (in Japanese with English Abst.) 5. Hirano M. Surgical treatments for dynamic disorders of swallowing.Jibi-inkoukaRinsyo (Practica Otologica) 1980; 73: 1667-1670. (in Japanese) 6. Duranceau AC, Jamieson GG, Beauchamp G. The technique of cricopharyngeal myotomy.Surg Clin North Am 1983; 63: 833-839. 7. Hirano M, Shin T, Yoshida Y, MaeyamaT, Nozoe I, Yoshida T. Infrahyoid myotomy--a surgical treatment for some dysphagia and speech disorders. Nippon Jibi-inkouka Gakkai Zasshi (Jpn J Otolaryngol) 1976; 79: 988-992. (in Japanese with English Abst.) 8. Naffziger HC. Paralysis of deglutition, surgical correction. Ann Surg 1948; 128: 732-742. 9. Hirano M, Yoshida T, Ohkubo H, Kufita S: Transcutaneous infrafold injection for vocal fold paralysis. Transact Am Bronch-Esophagol Assoc 1985; 115-117. 10. Hirano M, Shin T, Yoshida T, Mihashi S, Yoshida T, Okubo H. Clinical classification of aspiration caused by dynamic disorders of swallowing. Nippon Kikan Shyokudouka Gakkai Kaiho (Jpn J Bronchoesophagol Soc)1980; 31: 285-290. (in Japanese with English Abs't.)
692
Fujita et al.
11. Machimura T, Makuuchi H, Sugihara T, So Y, Shimada H, Mizutani K, Sugano K, Sasaki T, Tajima T, Mitomi T. Analysis of the swallowing movement for dysphagia after esophageal cancer operanon with videoradiography. Nippon Geka
_ Jpn. J. Surg. November 1991
Gakkai Zasshi (Jpn J Surg Soc) 1989; 90: 286. (in Japanese) 12. Hambraeus GM, Ekberg O, Fletcher R. Pharyngeal dysfunction after total and subtotal oesophagectomy. Acta Radiol 1987; 28: 409-413.
