Prevention of esophageal strictures in a caustic burn model using halofuginone, an inhibitor of collagen type I synthesis

OBJECTIVE: Esophageal strictures caused by caustic injury continue to be a plaguing problem. Halofuginone (HF) has been proven to inhibit the formation of fibrosis in various animal models and human diseases. Its mechanism appears to be through the suppression of the production of collagen alpha1(I) and transforming growth factor-beta signaling pathway. We tried to assess whether HF would have an effect on the formation of strictures after inducing caustic esophageal. MATERIALS AND METHODS: Esophageal injury was caused by injecting 25% NaOH to an isolated esophageal segment. Study group rats were treated with HF orally for 3 consecutive days before the injury and afterward. Control group rats received regular chow. The results were evaluated by upper gastrointestinal series (UGI) and through pathologic studies. RESULTS: HF treatment resulted in marked improvement in the esophageal strictures. The UGI series showed esophageal patency of 73% (45%-100%) in the treated animals (n = 7) as compared with almost no patency, 11% (5-16%), in the controls (n = 4) (P = .018). The histologic examination showed significantly less stricture and scarring in the treated group. Whereas the ratio between the esophageal wall thickness to mucosal thickness was 2.34 +/- 0.23 in the study group, the control group had a ratio of 9.56 +/- 0.69 (P = .0044). Finally, whereas 86% of the study group survived, all the rats in the control group died by day 20. CONCLUSIONS: HF modulated the wound healing reaction caused by caustic injury of the esophagus in a rat model, resulting in increased esophageal patency, reduction in esophageal wall thickness, and increased survival.     

Corrosive esophageal injuries in children. A shortlived experience in Sierra Leone

OBJECTIVE: Children with caustic ingestions in developing countries are often treated at home, sometimes by traditional healers, or are referred, frequently late, to tertiary hospitals, which only seldom offer adequate endoscopic and dilatation facilities. Therefore, when dilatations are performed, the stricture is often already well established, making dilatation more difficult. The aim of this paper is to report our experience in the management of corrosive injuries in a group of children of Sierra Leone, all complaining accidental ingestion of caustic soda, many of them treated months after the ingestion. METHOD: We considered all children admitted after corrosive ingestion, from November 2001 to November 2005, to the "Emergency" Surgical Center in Goderich-Freetown, Sierra Leone. In December 2005 the hospital was supplied with endoscopes and dilatation devices. The children still followed up clinically were recalled to submit them to an endoscopic follow-up and to a dilatation, if needed. RESULTS: Forty children were admitted (mean age: 4.5 years): 16 (group A) after an esophageal perforation during dilatation performed elsewhere (death rate: 56%). Twenty-four children (group B) were observed after ingestion, 58% being submitted to a surgical gastrostomy. Death rate after ingestion was nil. The mean interval between ingestion and endoscopy was 8.8 months. Fifty-three dilatations were carried out in 17 children over a 3 months period. We report three perforations (17.6%) and a death rate of 5.8% (1/17). Two patients were lost to follow-up. Three patients (17.6%) did not show any improvement. Four children complained recurrent dysphagia after the first dilatation cycle. Overall, 10 children (58.8%) showed a clear-cut improvement at 6 months. CONCLUSIONS: The majority of treated strictures were late, therefore difficult to dilate and at higher risk of perforation. Dilatation with Savary bougies seems safer than with balloon catheters. Recurrent strictures and a long-term dilatation treatment should be expected. Retrograde dilatations through gastrostomies should be the preferred method of treatment and surgical gastrostomies should be performed without hesitation. Esophageal replacement is unlikely in these countries, except in very few referral centres. Therefore, any effort should be made to treat caustic strictures by timely dilatation programs.     

Ingestion of caustic substances: a 15-year experience

OBJECTIVE: The objective of this study was to analyze the circumstance, demographic features, clinical findings, and complications of caustic ingestion in relation to the type and amount of caustic substance. STUDY DESIGN: The authors conducted a retrospective cohort study in a tertiary medical center. METHODS: The authors reviewed medical records from 1988 to 2003 of patients with a history of caustic ingestion and clinical signs of injury to the aerodigestive tract. Parameters examined included age at presentation, gender, demographic status, nature of the caustic substance ingested, amount of substance, circumstance of the event, diagnostic tools, degree of injury, and anatomic distribution of the injury, early and late complications, and requirement for ventilatory support. RESULTS: A total of 50 cases of caustic ingestion were identified (age range, 5 months-71 years). A biphasic distribution of the patients was noted; half were children under 5 years old and the remainder was adults. The most common caustic agent ingested was alkaline (42%) followed by acidic (32%) and chlorine bleach (26%). The most frequent cause for ingestion was accidental (67%) as opposed to attempt suicide (33%). All cases of attempted suicide occurred in adults. Most of them reported ingestion of large amounts of caustic substance. In the pediatric group, an association between the caustic agent and ethnicity was observed. Among Jewish children, alkaline cleaning agents were the most common cause (82%). Acetic acid was the most common substance ingested by the Arab children (100%). The findings of rigid esophagoscopy in 36 patients were as follows: first-degree esophageal injury in 16 (44%), second-degree in 6 (17%), third-degree in 7 (19%), fourth-degree in 6 (17%), and one (3%) was normal. Mucosal injury to the esophagus was worse in the acidic ingestion group as compared with the alkaline substance ingestion group with marginally statistically significant difference in the median degree of injury between the three types of ingested substances (P = .054). Mucosal injury to the esophagus was worse among patients who attempted suicide as compared with accidental ingestion with a statistically significant difference in the median degree of injury between the two reasons for ingestion (P = .002). CONCLUSION: Severity of injury from caustic ingestion damages depend on the type of ingested substance, which varies depending on ethnicity. Ingestion of caustic agents by children involves specific substances according to the season, cultural and religious festivals, and ethnicity. The majority of adult cases are intentional with more serious injuries and a higher rate of complications. In our series, ingestion of acidic substances and ingestion associated with suicide attempt had the most severe consequences.     

Esophageal caustic injury in childhood. A critical elucidation with indication for esophagoscopy

From 1983 through 1988, esophagoscopies were performed in 41 children because of suspected caustic esophageal injury. Of these 41 children, 11 had endoscopically significant esophageal burns and were treated with steroids and antibiotics. Of these 11 patients, two had no chemical burns of the facial skin, mouth, or pharyngeal mucosa. The authors therefore believe that esophagoscopy must not be omitted in cases of suspected caustic ingestion.     

Role of caffeic acid phenethyl ester, an active component of propolis, against NAOH-induced esophageal burns in rats

OBJECTIVES: This study was evaluated to investigate the efficacy of caffeic acid phenethyl ester (CAPE), which is a natural honeybee product exhibits a spectrum of biological activities including anti-microbial, anti-inflammatory, antioxidant and anti-tumoral actions, on the prevention of stricture development after esophageal caustic injuries in the rat. METHODS: Thirty healthy male Wistar albino rats were utilized in this study. The rats were randomly allotted into one of three experimental groups: group A (sham) animals were uninjured. Caustic esophageal burn was created by applying 1 ml 37.5% NaOH to the distal esophagus. Group B rats were injured but untreated. Group C rats were injured and received CAPE (10 micromol/kg/day i.p. for 28 days). Efficacy of the treatment was assessed by measuring the esophageal transit time, stenosis index, histopathologic damage score and biochemically by determining tissue hydroxyproline content, lipid peroxidation and antioxidant enzyme activities. RESULTS: The esophageal transit time, the stenosis index, histopathologic damage score and the hydroxyproline level were significantly increased in the untreated group compared with the sham and CAPE-treated groups. Treatment with CAPE decreased tissue hydroxyproline levels, histological damage, and the stenosis index, but except the esophageal transit time. Caustic esophageal burn also increased the lipid peroxidation and decreased the antioxidant enzyme activities in the untreated group. CAPE treatments decreased the elevated lipid peroxidation and also increased the reduced antioxidant enzyme activities. In corrosive esophageal burn group with no treatment, the most consistent findings were degenerative changes and increased in submucosal collagen content, and the luminal narrowing. CAPE treatment protected esophagus. Nevertheless, there was the slight increase in submucosal collagen. CONCLUSIONS: It is concluded that CAPE has a preventive effect on the stricture development after esophageal caustic injuries in the rat.     

Absence of esophageal injury in pediatric patients after hair relaxer ingestion.

OBJECTIVE: To review the initial signs, symptoms, and endoscopic findings in children admitted to the hospital for ingestion of caustic hair relaxer. DESIGN: Retrospective medical chart review of all children admitted to the hospital with a diagnosis of caustic ingestion from January 1, 1992, to June 30, 1997. Demographics, admission signs and symptoms, and operative findings were recorded from the medical records. SETTING: An urban tertiary care children's hospital. PATIENTS: Fifty-nine children (<3 years old) admitted to the hospital for ingestion of hair relaxers. RESULTS: Two hundred nine patients were evaluated for possible caustic ingestion. Only 163 medical charts were available for review. Of these, 59 (36.2%) ingested hair relaxers. Initial signs and symptoms ranged from none to drooling and vomiting and second-degree oral cavity bums. Fifty-six patients (95%) underwent endoscopy, which revealed normal esophageal mucosa in 53 of them, mild erythema of the distal esophagus in 2, and mild esophagitis in 1. CONCLUSIONS: In our experience, hair relaxer ingestion makes up a significant proportion of all children admitted to the hospital for caustic ingestion. No significant esophageal injury was associated with hair relaxer ingestion, suggesting that endoscopy may not be necessary in these patients. Alternative management is suggested. We believe that patients who ingest hair relaxer should be admitted to the hospital for observation if parents are thought to be unreliable, and should undergo endoscopy if they cannot tolerate oral intake. Asymptomatic patients may be cared for as outpatients if they demonstrate adequate oral intake.     

气管食管裂隙状发声孔发声机制研究

目的：探讨气管食管裂隙状发声孔的发声机制。方法：用大功率遥控X线机和动态频闪喉镜观察40例行全喉切除，Ⅰ期或Ⅱ期发声重建术患者发声时的贮气相、送气相、发声相。结果：患者吸气时肺部膨隆，食管黏膜闭拢；食管入口黏膜内翻呈环形缩小；随之，下咽腔增大呈一尖端向下的三角锥形；食管上端迅速膨大。发声开始时，食管上端扩张如球，食管人口黏膜以冠状位呈唇样外翻，气体从咽食管部冲出；黏膜、黏液发生振动，发出基音。后胸廓缩小，食管入口黏膜再次内翻，发声结束。结论：气管食管音发声的动力器官是肺，气管-食管造瘘口的通畅对发声至关重要。发声时，下咽黏膜、食管口黏膜与黏液均参与振动。     

Beneficial effects of Ebselen on corrosive esophageal burns of rats

AIM: This study was evaluated to investigate the efficacy of Ebselen, which is an organoselenium compound and glutathione peroxidase mimic, on the prevention of stricture development after esophageal caustic injuries in the rat. METHODS: Thirty healthy male Wistar albino rats were utilized in this study. The rats were randomly allotted into one of three experimental groups: group A (sham) animals were uninjured. Caustic esophageal burn was created by applying 1 ml of 37.5% NaOH to the distal esophagus. Group B rats were injured but untreated. Group C rats were injured and received Ebselen (10 mg/kg/day) via the oral route. Blood and tissue samples for the biochemical and histopathological analysis were taken all rats at the end (28th day) of the experiment. Oxidative stress is believed to play a role in the pathogenesis of corrosive esophageal burns. To assess changes in the cellular antioxidant defense system, we measured the activities of antioxidant enzymes (such as glutathione peroxidase (GSHPx), superoxide dismutase (SOD), and catalase (CAT)) in esophagus homogenates. We also measured esophageal tissue malondialdehyde (MDA) levels, a marker of lipid peroxidation, to determine whether there is an imbalance between oxidant and antioxidant status. Efficacy of the treatment was assessed by measuring the stenosis index and histopathologic damage score and biochemically by determining tissue hydroxyproline content, lipid peroxidation and antioxidant enzyme levels. RESULTS: The stenosis index in group B was significantly increased compared with group A and C (P<0.05). The hydroxyproline level was significantly increased in group B compared with group A and C (P<0.05). In group B, the histopathologic damage score was significantly higher than in group C (P<0.05). Treatment with Ebselen decreased tissue hydroxyproline levels, histological damage, and the stenosis index. Caustic esophageal burn increased the lipid peroxidation and also decreased the antioxidant enzyme levels in group B. Ebselen treatments for 28 days decreased the elevated lipid peroxidation and also increased the reduced antioxidant enzyme levels. Live weights of the rats was significantly decreased in group B compared with group A and C (P<0.05). CONCLUSION: It is concluded that Ebselen has a preventive effect in the development of fibrosis and decrease the lipid peroxidation, and increase the antioxidant defense system activity in an experimental model of corrosive esophagitis in rats.     

豚鼠变应性鼻炎模型鼻黏膜的病理改变

目的：观察变应性鼻炎鼻黏膜的病理变化。方法：用橄榄油将甲苯-2,4-二异氰酸酯配成浓度为10%的溶液作为致敏剂,滴鼻,建立豚鼠变应性鼻炎动物模型8例。8例正常豚鼠作对照。致敏结束、模型成功后,取两组鼻黏膜组织,光镜下观察病理变化。结果：模型组鼻黏膜上皮脱落,杯状细胞增生,鳞状上皮组织转化,上皮坏死,固有层和黏膜下层腺体增生,血管扩张,组织水肿,并见特征性的嗜酸性粒细胞、肥大细胞浸润,这种病理改变与变应性鼻炎的临床表现大致吻合。对照组鼻黏膜上皮层为假复层纤毛柱状上皮,连续、完整、清晰,可见正常的黏膜上皮层、固有层和黏膜下层。结论：变应性鼻炎鼻黏膜出现特征性的炎症病理改变。     

Inhibition of iNOS with S-methylisothiourea was impaired in wound healing in caustic esophageal burn

OBJECTIVE: Stricture formation is a late complication of caustic esophageal burn, which is a common problem in childhood. For this reason, this experimental study was designed to observe the possible effect of nitric oxide on healing and fibrosis formation in caustic esophageal burns. MATERIALS AND METHODS: The rats were divided into five groups. Group A (n=12) received sham burn and treatment with saline injection. Group B (n=34) received caustic burn. Rats in group C (n=31), were given water supplement with 10 g/L L-arginine that was started 24 h preoperatively and continued until postoperative day 4. In group D (n=21), S-methylisothiourea (SMT, specific inducible nitric oxide synthase (iNOS) inhibitor), was injected at a dose of 3 mg/kg i.p. at 30 min before caustic burn, and similar dose was reinjected immediately after caustic burn. SMT 6 mg/kg/day injections continued for 4 days long. In group E (n=22), Nomega-nitro-L-arginine (L-NNA, nonspecific nitric oxide synthase (NOS) inhibitor) was injected at a dose of 15 mg/kg i.p. at 30 min before caustic burn, and similar dose was reinjected immediately after caustic burn. L-NNA 30 mg/kg/day continues for 4 days. RESULTS: Dead rates were significantly higher in group E than in groups A-D. The mean hydroxyproline levels in esophageal tissue were significantly lower in groups A and B than in group D. Histopathologically, tissue damage scores in the esophageal tissue were higher in group D than in groups A-C. CONCLUSIONS: Inhibition of iNOS with SMT was impaired in wound healing due to caustic esophageal burn and provoked collagen accumulation at a later period. Those effects may due to inhibition of antioxidant, immunomodulatory and antifibrotic effects of NO.     

Study by radiolabelling of the residual time of a therapeutic gel in the nasal fossae

The residence times in the nose of the liquid and gel forms of the same therapeutic preparation were compared in 7 healthy subjects. A 50 microliters drop of the preparation, labelled with Tc99m, was placed down the head of the inferior turbinate, and the kinetics of its clearance from the site of deposition was monotired using a gamma camera, during 60 minutes for the liquid and 120 minutes for the gel. The average times for removal of 50% of the labelled material from the site of deposition were 10.3 minutes and 28.6 minutes for the liquid and gel forms respectively. The slower removal of the gel form is probably due to a mechanical effect, and seems to affect the whole nasal passage. The contact time between the preparation and the mucosa is increased in this galenic form and this should improve the efficiency of the preparation.     

Corrosive esophagitis in children: a 30-year review

Caustic ingestion with resultant corrosive esophagitis in the pediatric population comprises a heterogeneous group in terms of offending agent, location of burn and the degree of damage. Consequently, the treatment of these injuries has also varied over the years and the optimal management remains controversial. Another area of concern that is seldom reported in the otolaryngology literature is the socioeconomic impact of such injuries both on the child and on the family. We report a 30-year retrospective review of aerodigestive tract caustic injuries at The Hospital for Sick Children. Eighty patients were identified with an age range from 1 month to 16 years. Early and late complications are reviewed including 23 patients (29%) that developed medical complications and 16 patients (20%) that developed severe esophageal strictures. Five of these children required repeat prograde dilatation, while 11 children required gastrostomy and stringing with subsequent retrograde dilatation. All the 11 children required esophageal replacement surgery. The economic and social consequences to the child and family were also noted with particular attention to hospital costs, parental absenteeism from work, and the need for job relocation. A partial cost analysis using a child with a severe injury is presented as an example. Psychological aspects such as attempted murder, jail terms and attempted suicides are also documented. We also present an analysis of those children requiring esophageal replacement surgery, and examine the possible role of esophageal stents in recalcitrant strictures.     

Vascular degeneration in otosclerosis and its influence on the mesenchymal reaction of the mucoperiost]

38 samples of middle ear mucosa were taken from different patients during stapes surgery in otosclerosis. The samples were studied light-and electronmicroscopically without decalcification. Considerable pathologic changes in the organisation of the capillaries (endothelial hydrops, proliferation of the intima and of the adventitia, total obliteration o the vessels) cause pathologic reactions on the mesenchymal elements of the submucosa. Next to fibrolysis or hyalinosis of the collagen fibers the fibrocyts show features of undergoing lysis. Free and cellular bound calcium deposits are located in these lytic areas. The epithelial lining also shows unusual inclusions as glycogen and acid mucopolysaccharides and an alterated basement membrane. We belive that the changes of the connective tissue and of the epithelium are secundary to the capillary obstruction.     

Validation of animal experiments on ciliary function in vitro. II. The influence of absorption enhancers, preservatives and physiologic saline

Ciliary beat frequency (CBF) is one of the most important parameters of mucociliary clearance. Previously, we demonstrated that mucosa from chicken embryo trachea is a good substitute for human ciliated epithelium to study the effects on CBF of substances that are used clinically. In this study, we examined the effect on CBF of four excipients for nasal drug formulations: the absorption enhancers methylated beta-cyclodextrin 2% and sodium taurodihydrofusidate 1%, the preservative benzalkonium chloride 0.01%, and physiologic saline. We also examined the effect on CBF of the cryopreservative dimethyl sulfoxide, which is used to protect ciliated epithelium prior to storage in liquid nitrogen. Results obtained with chicken embryo trachea were compared with those of cryopreserved human mucosa taken from the sphenoidal sinus. For all of the substances tested, the effects on CBF of chicken material were comparable to those measured on human material. Benzalkonium chloride had a stronger ciliostatic effect on human tissue. After 60 min, however, the effect of that substance on CBF was similar in both tissues. We conclude that chicken embryo trachea can be used as a substitute for human ciliated mucosa when studying ciliary activity in vitro.     

胃上提结肠上徙在下咽食管病变切除后缺损修复中的应用

目的:探讨下咽、食管肿瘤及狭窄病变切除后,采用胃上提结肠上徙进行食管重建的手术适应证和术后并发症。方法:回顾性分析行胃上提咽胃吻合52例、结肠上徙咽结肠吻合66例患者的临床资料,其中肿瘤组87例,行胃上提52例,结肠上徙35例;下咽食管腐蚀性狭窄和闭锁组31例,均行结肠上徙食管重建。结果:肿瘤组胃上提52例中保留喉功能28例;结肠上徙35例中保留喉功能18例,选择不同的食管修复方法对喉功能保留无明显影响(P>0.05)。但结肠上徙组咽瘘发生率25.8%(17/66)明显高于胃上提组9.6%(5/52)(P<0.05)。胃上提组胃液反流发生率30.8%(16/52)明显高于结肠上徙组4.5%(3/66)(P<0.05)。结论:胃上提结肠上徙食管修复术可以在彻底切除下咽、颈段食管肿瘤的同时,保留部分患者的喉功能。由于胃上提患者术后胃液反流的发生率较高,且吻合口位置较高,对保留喉功能的下咽或食管肿瘤临床上仍主张采用结肠上徙修复。但由于结肠血液供应不如胃组织丰富,咽-肠吻合口瘘的发生率较高。     

接触性内镜在早期喉癌及其癌前病变诊断中的应用

目的探索接触性内镜对早期喉癌及其癌前病变行微创病理学诊断的可行性。方法86例喉病变患者,在显微支撑喉镜下,于喉内病变处黏膜涂1%美蓝染色,将60×和150×接触性内镜置于黏膜表面,观察其病理变化,并与活检结果比较。结果接触性内镜的电子图像可较清晰显示表面黏膜不同病变细胞及核的大小、形状、排列、胞浆比、致密度和着色情况,有无中空细胞、核角蛋白,黏膜下微血管的排列情况。病理改变包括:任克式水肿(n=8),慢性喉炎(n=15),喉乳头状瘤(n=8),黏膜白斑(n=9),声带非典型性增生(n=18),恶性肿瘤(n=22),其他6例。结论接触性内镜作为一种新的微创性辅助检查方法,可用于喉癌及其癌前病变的诊断和动态随访。     

辐射对豚鼠鼻黏膜组织结构及微血管的影响

目的：探讨辐射对豚鼠鼻黏膜结构及微血管的损伤。方法：选择健康豚鼠84只，随机分为对照组（12只）及照射组（72只）。均在同样条件下喂养。将照射组豚鼠置于直线加速器射线内照射，每周1次，每次照射5Gy，计3周，总剂量15Gy，建立辐射损伤动物模型。分别于照射后0．5、1.0、2．0、3．0、5．0、6．0个月处死动物12只，随机取6只做鼻腔黏膜微血管铸型，另6只做病理检查。对照组在假照射后6个月处死动物，随机各选6只分别做鼻黏膜微血管铸型检查和病理检查。结果：照射组豚鼠的鼻黏膜辐射后早期表现为急性炎症反应，黏膜大量坏死、脱落，电镜下见仅少部分黏膜表面还被覆着正常的纤毛结构。以后黏膜开始修复，至6个月时基本结束，但大部分黏膜失去了正常的纤毛柱状上皮结构特点，部分区域甚至代为组织转化的鳞状上皮；微血管铸型可见，早期改变为毛细血管扩张充血及血管内皮细胞肿胀，以后逐渐出现毛细血管的扭曲变形、闭塞及中断，毛细血管数量大量减少，致血液回流障碍，微静脉萎瘪。后期部分区域出现新生的毛细血管，但结构紊乱，不具备微循环的功能。结论：鼻黏膜的损伤、晚期的鳞状上皮组织转化以及鼻黏膜微循环的破坏是放疗后鼻腔功能障碍的病理学基础。     

Cefotetan in the treatment of sinusitis--a kinetic study

Recent clinical experience shows that in treating sinusitis by tetracyclines more and more cases appear which are resistant to therapy. Cephalosporins are suitable as alternative medical treatment because of their good bactericidal effect. The pharmacokinetic qualities of Cefotetan, a new cephamycin-antibiotic, in plasma and sinus mucosa were examined in treating 13 patients. After an intravenous bolus-injection of 2 g Cefotetan the mean initial plasma concentration was 275 mg/l. After 1, 2 and 6 hours the plasma levels were 160, 96 and 39 mg/l. The average concentration in sinus mucosa reached 42.3 mg/l, 30.9 mg/l, 29.4 mg/l and 33.6 mg/l after 10, 60, 120 and 180 minutes. The pharmacokinetic properties of Cefotetan promise successful clinical application in the treatment of bacterial sinusitis.     

Rabbit model of airway stenosis induced by scraping of the tracheal mucosa

BACKGROUND: Prolonged endotracheal intubation in children often induces intractable airway stenosis. The aim of the present study was to establish a new model of airway stenosis for developing an effective method of treatment. MATERIAL AND METHODS: The rabbit trachea was annularly incised, and the tracheal mucosa was scraped with a nylon brush. The trachea was then closed. Nine days after scraping, the trachea was microscopically examined. RESULTS: All of the examined rabbits showed tracheal stenosis, ranging from 22% to 82% in diameter and from 48% to 97% in cross-sectional area. The stenotic lesion was confined within the scraped region, not including the sutured region. Histologic examination showed inflammation in the stenotic lesion with submucosal hyperplasia caused by proliferation of fibroblasts and thickening of collagen fibers. CONCLUSION: This method can be easily carried out and assures induction of airway stenosis. This model may be useful for developing methods for treating airway stenosis in the early stage.     

Corrosive esophageal injuries. II. An investigation of treatment methods and histochemical analysis of esophageal strictures in a new animal model

The unique clinical experience of having to treat simultaneously nine young adults who had ingested the same corrosive substance prompted this investigation in rabbits of the pathophysiology of corrosive esophageal injury and of drugs that might prevent formation of stricture. Treatment of experimental corrosive esophageal injury in these animals consisted of antegrade dilatation and administration of two lathyrogenic drugs, colchicine and penicillamine, in various combinations. This study demonstrated that the rabbit can serve as a suitable animal model for study of corrosive injury of the esophagus, that penicillamine given alone affected wound healing with less severe stricture after such an injury, and that colchicine was associated with delayed wound healing and severe stricture.