• Clinical Endoscopy
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• v.56 no.5
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• pp.537-545
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• 2023

Achalasia is an esophageal motility disorder characterized by impaired lower esophageal sphincter relaxation and peristalsis of the esophageal body. With the increasing prevalence of achalasia, interest in the role of endoscopy in its diagnosis, treatment, and monitoring is also growing. The major diagnostic modalities for achalasia include high-resolution manometry, esophagogastroduodenoscopy, and barium esophagography. Endoscopic assessment is important for early diagnosis to rule out diseases that mimic achalasia symptoms, such as pseudo-achalasia, esophageal cancer, esophageal webs, and eosinophilic esophagitis. The major endoscopic characteristics suggestive of achalasia include a widened esophageal lumen and food residue in the esophagus. Once diagnosed, achalasia can be treated either endoscopically or surgically. The preference for endoscopic treatment is increasing owing to its minimal invasiveness. Botulinum toxins, pneumatic balloon dilation, and peroral endoscopic myotomy (POEM) are important endoscopic treatments. Previous studies have demonstrated excellent treatment outcomes for POEM, with >95% improvement in dysphagia, making POEM the mainstay treatment option for achalasia. Several studies have reported an increased risk of esophageal cancer in patients with achalasia. However, routine endoscopic surveillance remains controversial owing to the lack of sufficient data. Further studies on surveillance methods and duration are warranted to establish concordant guidelines for the endoscopic surveillance of achalasia.

• Journal of Chest Surgery
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• v.13 no.4
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• pp.470-474
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• 1980

Achalasia is a neurogenic esophageal disorder, characterized by incomplete relaxation of the gastroesophageal sphincter in response to deglutition and absence of peristalsis from the body of the esophaugs. Because there is no known method by which esophageal peristalsis can be restored, therapy is directed toward the relief of dital esophageal obstruction. During the period of June 1965 to September 1980, 13 cases of achalasia were operated at the Department of Thoracic SUrgery, Seoul Natonal University Hospital. 1. Among 13 cases, 5 were male and 8 were female. 2. Esophagomyotomy was performed in 12 cases, and 1 case was treated with transverse suture of lower esophagus after longitudinal incision. 3. There was no operative mortality, but 2 cases subsequently underwent esophagogastrostomy after esophagomyotomy. 4. One of 13 cases was combined with mongolism.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1997.11a
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• pp.41-46
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• 1997

Lower esophageal sphincter (LES) is characterized by the ability to maintain a sustained pressure, and to relax allowing the passage of a bolus, whereas the esophagus is normally relaxed and contracts only briefly when required to produce peristalsis (fig. 1). The neuromuscular mechanisms that participate in the physiological regulation of these functions are not well understood, but it is thought that LES tone is spontaneous and regulated mostly through myogenic mechanisms, whereas LES relaxation and esophageal contraction are induced by neural mechanisms. Gastroesophageal reflux represents the effortless movement of gastric contents from stomach to esophagus. Because this phenomenon occurs in virtually everyone multiple times every day and in the majority of people without clinical consequences, the reflux per se is not disease. However in some cases, it can be pathologic, producing symptoms and signs called gastroesophageal reflux disease (GERD), which mechanism is not well known. It may result in heart burn, chronic esophagitis, aspiration pneumonia, esophageal strictures, and Barrett's esophagus.

• Journal of Veterinary Clinics
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• v.23 no.3
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• pp.371-374
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• 2006

A 4-month-old, intact male, Tosa with a history of a regurgitation, vomiting, and weight loss for three weeks was presented to Animal Medical Center, Chonbuk National University. In Serial plain radiographs, a severely distended stomach was seen and ultrasonogram revealed a nonfunctional pylorus with normal layer comparable with an obstruction of pyloric region by pyloric achalasia. An esophagram and endoscopy revealed normal peristalsis with failure of the lower esophageal sphincter to open, supporting the diagnosis of esophageal achalasia. Megaesophagus was observed on reradiograph and esophagram 11 days later. The clinical signs and esophageal dilation were resolved without resorting to any treatment.

• Journal of Chest Surgery
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• v.53 no.4
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• pp.217-221
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• 2020

Gastroesophageal reflux is a common problem after gastroesophageal resection and reconstruction, despite the routine prescription of proton pump inhibitors (PPIs). Resection of the lower esophageal sphincter and excision of the vagus nerve are generally thought to be the main factors that interfere with gastric motor function. However, physiological studies of reflux symptoms after esophagectomy are still lacking. Gastroesophageal reflux occurs frequently after esophagectomy, but there is no known effective method to prevent it. Therefore, in order to manage gastroesophageal reflux after esophagectomy, strict lifestyle modifications and gastric acid suppression treatment such as PPIs are needed, and further clinical studies are required.

• The Korean Journal of Physiology and Pharmacology
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• v.1 no.3
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• pp.303-313
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• 1997

The role of the lower esophageal sphincter(LES) is characterized by the ability to maintain tone and to relax allowing the passage of a bolus. It is known that LES relaxation during swallowing may be induced by the cessation of the tonic neural excitation and the activation of non-adrenergic, non-cholinergic(NANC) inhibitory neurons. Furthermore, it is generally accepted that the relaxation of the smooth muscle is mediated primarily by the elaboration of adenosine 3',5'-cyclic monophosphate(cyclic AMP) and guanosine 3',5'-cyclic mono-phosphate(cyclic GMP) via activation of adenylate cyclase and guanylate cyclase, respectively. It is thus possible that cyclic nucleotides might be a second messenger involved in neural stimulation-induced relaxation of LES, although a relationship between relaxation and changes in cyclic nucleotides after neural stimulation has not been established. The present study was performed to define the participation of cyclic nucleotides in the relaxation of LES of dog in response to neural stimulation. Electrical field stimulation(EFS) caused relaxation of the canine isolated LES strips in a frequency-dependent manner, which was eliminated by pretreatment with tetrodotoxin$(1{\mu}M)$, but not by atropine$(100{\mu}M)$, guanethidine$(100{\mu}M)$ and indomethacin$(10{\mu}M)$. The nitric oxide synthase inhibitors, $N^G-nitro-L-arginine$, $N^G-nitro-L-arginine$ methyl ester and $N^G-monomethyl-L-arginine$ inhibited EFS-induced relaxation. Additions of sodium nitroprusside, a nitrovasodilator and forskolin, a direct adenylate cyclase stimulant, caused a dose-dependent relaxation of LES smooth muscle. Effects of sodium nitroprusside and forskolin were selectively blocked by the corresponding inhibitors, methylene blue for guanylate cyclase and N-ethylmaleimide(NEM) for adenylate cyclase, respectively. Dibutyryl cyclic AMP and dibutyryl cyclic GMP caused a concentration-dependent relaxation of the LES smooth muscle tone, which was not blocked by NEM or methylene blue, respectively. However, both NEM and methylene blue caused significant antagonism of the relaxation in LES tone in response to EFS. EFS increased the tissue cyclic GMP content by 124%, whereas it did not affect the tissue level of cyclic AMP. Based on these results, it is suggested that one of the components of canine LES smooth muscle relaxation in response to neural stimulation is mediated by an increase of cyclic GMP via the activation of guanylate cyclase. Additionally, an activation of cyclic AMP generation system was, in part, involved in the EFS-induced relaxation.

• Archives of Pharmacal Research
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• v.24 no.6
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• pp.546-551
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• 2001

We have previously shown that, in circular muscle cells of the lower esophageal sphincter (LES) isolated by enzymatic digestion, contraction in response to maximally effective doses of acetylcholine (ACh) or Inositol Triphosphate ($IP_3$) depends on the release of $Ca^{2+}$ from intracellular stores and activation of a $Ca6{2+}$-calmodulin (CaM)-dependent pathway. On the contrary, maintenance of LES tone, and response to low doses of ACh or $IP_3$ depend on a protein kinase C (PKC) mediated pathway. In the present investigation, we have examined requirements for $Ca6{2+}$ regulation of the interaction between CaM- and PKC-dependent pathways in LES contraction. Thapsigargin (TG) treatment for 30 min dose dependently reduced ACh-induced contraction of permeable LES cells in free $Ca6{2+}$ medium. ACh-induced contraction following the low level of reduction of $Ca6{2+}$ stores by a low dose of TG ($10^{-9}{\;}M$) was blocked by the CaM antagonist, CCS9343B but not by the PKC antagonists chelerythrine or H7, indicating that the contraction is CaM-dependent. After maximal reduction in intracellular $Ca{2+}$ from $Ca6{2+}$stores by TG ($10^{-6}{\;}M$), ACh-induced contraction was blocked by chelerythrine or H7, but not by CCS9343B, indicating that it is PKC-dependent. In normal $Ca^{2+}$medium, the contraction by ACh after TG ($10^{-9}{\;}M$) treatment was also CaM-dependent, whereas the contraction by ACh after TG ($10^{-9}{\;}M$) treatment was PKC-dependent. We examined whether PKC activation was inhibited by activated CaM. CCS 7343B Inhibited the CaM-induced contraction, but did not inhibit the DAC-induced contraction. CaM inhibited the DAC-induced contraction in the presence of CCS 9343B. This inhibition by CaM was $Ca{2+}$dependent. These data are consistent with the view that the switch from a PKC-dependent pathway to a CaM dependent pathway can occur and can be regulated by cytosolic $Ca{2+}$ in the LES.

• Proceedings of the PSK Conference
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• 2002.04a
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• pp.123.2-123.2
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• 2002

• Journal of Chest Surgery
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• v.17 no.4
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• pp.792-795
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• 1984

The modified Hellers myotomy for esophageal achalasia is known as the best procedure. A properly performed transthoracic esophagomyotomy is essential to prevent complications. But it has some problems such as persistent achalasia due to inadequate myotomy, recurrence due to the healing of myotomy and reflux esophagitis due to destruction of the lower esophageal sphincter. The methods of the reoperation after esophagomyotomy for achalasia of the esophagus consist of 1 ] for persistent achalasia due to inadequate myotomy, additional myotomy feasible. 2] for esophageal reflux, a long-limb jejunal gastric drainage after vagotomy and hemigastrectomy, jejunal after conservative resection for stricture. We experienced 3 cases of reoperation after esophagomyotomy for achalasia of the esophagus. The 1st and 3rd case belongs to 30 cases which were undertaken the primary operation at the National Medical Center from 1961 to 1984. The 2nd case was undertaken the primary operation at other hospital. The 1st and 3rd case were reoperated because of persistent achalasia due to inadequate myotomy and 2rid case was caused by stricture due to reflux esophagitis. The methods of the reoperation were additional myotomy in 1st case, esophagogastrectomy and lower thoracic esophagogastrostomy in 2nd case, and esophagogastrectomy and mid-thoracic esophagogastrostomy in 3rd case. All three cases were complicated with postoperative reflux esophagitis.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.4 no.2
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• pp.218-223
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• 2001

Achalasia is a rare motor disorder of the esophageal smooth muscle in which the lower esophageal sphincter dose not relax properly with swallowing, and the normal peristalsis of the esophageal body is replaced by abnormal contractions. Achalasia has been described as party of several distinct multisystem syndromes suggesting a generalized neuromuscular disorder as the mode of origin. An 11-year-old female was admitted because of paresthesia on the trunk and both legs for 5 days. She had suffered from chest discomfort, dysphagia, postprandial vomiting, and weight loss for 6 months. She was diagnosed as having achalasia by means of the esophagography and esophageal manometry. Her chest discomfort, dysphagia and vomiting much improved after the endoscopic balloon dilatation. The authors present an 11-year-old female with achalasia complained of paresthesia and sucessfully managed by the balloon dilatation.