Segment Of Esophagus Research Articles

Capacity of flexible endoscopy in subepithelial esophageal tumors

Aim of the study was to investigate the results of endoscopic diagnostics and peroral operative endoscopy in subepithelial esophageal tumors. Material and methods. Data of 21 patients underwent flexible endoscopic interventions for subepithelial esophageal tumors (SET) from 2016 till 2019 were analyzed. Main endoscopic methods to reveal and characterize tumors preoperatively are examination in white light, narrow light spectrum imaging, radial endoscopic ultrasonographic scanning. Tumors from 8 till 40 mm in maximal dimension removed by endoscopic mucosal resection (2 tumors in 1 patient), tunnel dissection (13 cases) or endoscopic submucosal dissection (7 cases). The additional endoscopic ultrasonography was demanded intraoperatively in 2 cases of difficult tumor location and blurry visualization. Results and discussion. Subepithelial esophageal tumors are mainly diagnosed occasionally in patients without symptoms related to tumor. Suspicion of the tumor was based on routine esophagogastroduodenoscopy. Following endoscopic ultrasonography of planned esophageal segment allowed rejecting or confirming the lesion (21 patients), evaluating its echoscopic structure, size, growth direction, intramural location and connection to wall layers to make an assumption related to tumor morphology, to plan way of tumor removal. We choose interventions in depends on combination of available tumor features. Technical success of endoscopic interventions with use of flexible endoscope under this approach is noted in all the patients. So endoscopic methods are important for primary and detailed diagnostics and also effective for operative treatment in cases of appropriate indications.

DIAGNOSIS OF GASTROESOPHAGEAL REFLUX IN INFANTS OPERATED FOR ESOPHAGEAL ATRESIA

30 children with esophageal atresia treated at our hospital during 2006-2009 were observed. All of them had the same variant of anomaly – type C esophageal atresia (with distal tracheal-esophageal fistula). The average gap between esophageal segments was 2 cm (ranging from 1.5 to 3 cm). The direct anastomosis was applied in all cases. The follow-up revealed development of anastomosis stricture in 2 children (6 %) associated with marked inflammatory changes at the distal 1/3 of esophagus caused by pathologic gastro-esophageal reflux. 14% of patients developed mild esophageal stenos (0.5–0.6 cm) without marked inflammation of mucosa. In 24 cases (80 %) there was no alteration at the anastomosis zone. We propose our scheme of observation and rehabilitation for patients with esophageal anastomosis.

Experimental Study of the Tissue Repair of Neo-Esophagus After Esophageal Muscularis Resection.

Attempts have been made to observe the tissue repair of neo-esophagus after esophageal muscularis resection and to investigate possibility of the regeneration repair of esophageal muscularis resection in neo-esophagus. Sixteen pigs were divided into two groups: group A and group B. Pigs in group A were performed with the partial resection of mere esophageal muscularis propria reserved mucosa muscle layer in a segment of thoracic esophagus. Pigs in group B were performed with nitinol composite artificial esophagus with polyester sewing rings replacement a segment of thoracic esophagus resection. Pigs in the two groups were performed with euthanasia at the following times: 2, 4, 6, and 12 months for postmortem analysis, which demonstrated the absence of esophageal muscularis regeneration in the specimens that were sampled from different time points. Reserved mucosa muscle layer did not show hyperplasia to repair coloboma of esophageal muscularis propria deletion in group A. These results suggest that after esophageal muscularis resection, including mucosa muscle layer or esophageal muscularis propria, the coloboma of esophageal muscularis was repaired with connective tissue filling quickly. It would be very difficult for the regeneration repair of esophageal muscularis in neo-esophageal tissue structure after esophageal muscularis resection.

Mapping patterns of metastatic lymph nodes for postoperative radiotherapy in thoracic esophageal squamous cell carcinoma: a recommendation for clinical target volume definition

BackgroundThe clinical target volume (CTV) for postoperative radiotherapy for thoracic esophageal squamous cell carcinoma (TESCC) needs to be defined. The study aim was to map metastatic lymph nodes (LNMs) in a computed tomography (CT)-based atlas and delineate the postoperative radiotherapy target area.MethodsSixty-nine TESCC patients with first recurrent regional LNMs after esophagectomy were included. The LNM epicenters were registered onto corresponding anatomic axial CT images of a standard patient in the treatment position, with reference to the surrounding vascular and bony structures. The LNM sites were based on lymph node map of esophageal cancer, AJCC 8th. The lymph metastasis risk for different segments of thoracic esophagus was assessed.ResultsOne hundred and seventy-nine LNMs were mapped onto standard axial CT images. The upper-middle mediastinum region (station 1 to 8 M) contained 97% of metastases in the upper segment of thoracic esophagus, 90% in the middle segment, and 66% in the lower one. Advanced pathological stage (≥IIIB) might be a predictive factor for upper abdominal region (UAR) relapse in lower TESCC. Lower cervical para-tracheal LNMs were within a 4.3-cm bilaterally expanded area from the midline of the body and a 2.2-cm expanded area from the anterior of vertebral body, from the superior border of the C7, to the inferior border of the first thoracic vertebra.ConclusionA modified target from the upper border of C7 to the lower border of caudal margin of the inferior pulmonary vein level could cover the high-risk area of TESCC underwent postoperative radiotherapy. UAR seems to be an elective irradiation target for lower TESCC at pathological IIIB stage and higher.

Comparison of Ivor Lewis esophagectomy and Sweet esophagectomy for the treatment of middle-lower esophageal squamous cell carcinoma.

For cancer of the middle and/or lower segment of thoracic esophagus, the Ivor Lewis esophagectomy is the mainstream standard surgery, whereas the Sweet procedure is widely used in China. As no consensus has been reached about the choice of different thoracic approaches, we designed this retrospective study to investigate and compare oncological benefits of the two surgical approaches. After propensity score matching, 150 patients who underwent the Sweet or Ivor Lewis esophagectomy from August 2003 to December 2009 in the Beijing Cancer Hospital were reviewed. We compared the postoperative recovery, nutritional parameters, and survival of the two different surgical approaches. The 5-year overall survival (OS) rate for the whole group was 48.5%, and the 10-year OS rate was 35.6%. The Ivor Lewis group had a longer operation time, longer duration of chest tube drainage, and a larger volume of total thoracic drainage. No significant differences were found between the two groups in terms of the duration of systemic inflammatory response syndrome (SIRS), length of postoperative hospital stay, duration of postoperative nasogastric tube use, incidence of major complications, and nutritional status after the esophagectomy. The OS rates were similar in both groups. The Sweet and Ivor Lewis esophagectomy are both safe and effective. A change of the surgical incision may not be the best way to increase survival, and the choice of surgical procedure should depend on the preference of the thoracic surgeon to secure the safety of the operation.

Detection of minimal mucosal esophageal lesions in non-erosive gastroesophageal reflux disease using optical enhancement plus optical magnification.

Background and study aims The aim of this study was to evaluate the diagnostic yield of endoscopy using optical enhancement (OE system) with optical magnification to predict reflux in non-erosive reflux disease (NERD) patients. Patients and methods A prospective, non-randomized, single-blind study was performed from September 2015 to January 2016. Participants suffered from gastroesophageal reflux disease (GERD) symptoms and were assigned to the NERD group or the non-reflux disease control group based on endoscopic findings and a 24-hour pH-impedance-monitoring test. Endoscopy using the OE system with optical magnification was performed in all patients to detect minimal mucosal esophageal lesions (MMEL), specifically abnormalities in the numbers, dilation, and tortuosity of intrapapillary capillary loops (IPCLs). Biopsies were obtained from each esophageal segment, and diagnoses from images were compared to diagnoses of reflux and inflammation using 24-hour pH-impedance monitoring and histology, respectively. Results Fifty-seven patients were included (36 in the NERD group, 21 in the control group). IPCLs were observed in 94.4 % of cases in the NERD group and 38 % of cases in the control group ( P < 0.05). There were significant differences in IPCL abnormalities between groups that were associated with histologically identified inflammation. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 94.4 %, 61.9 %, 80.9 %, 86.6 %, and 82.4 %, respectively. The 24-hour pH-impedance-monitoring test was used as the gold standard. The Kappa interobserver and intraobserver values were 0.85 and 0.90, respectively. Conclusion The OE system with optical magnification can detect MMEL and predict NERD with high sensitivity, accuracy, and interobserver and intraobserver agreement. Presence of IPCLs highly correlates with histologically identified inflammation.

Distinct neural-mechanical efficiency of costal and crural diaphragm during hypercapnia

Classic physiology suggests that the two distinct diaphragm segments, costal and crural, are functionally different. It is not known if the two diaphragm muscles share a common neural mechanical activation.We hypothesized that costal and crural diaphragm are recruited differently during hypercapnic stimulated ventilation, and the EMG recordings of the esophageal crural diaphragm segment does not translate to the same level of mechanical shortening for costal and crural segmentsIn 30 spontaneously breathing canines, without confounding anesthetic, we measured directly electrical activity and corresponding mechanical shortening of both the costal and crural diaphragm, at room air and during increasing hypercapnia.During hypercapnic ventilation, the costal diaphragm showed a predominant recruitment over the crural diaphragm. The distinct mechanical contribution of the costal segment was not due to a different level of neural activation between the two muscles as measured by segmental EMG activity. Thus, the two diaphragm segments exhibited a significantly different neural-mechanical relationship.

The Utility of High-Resolution Pharyngeal Manometry in Dysphagia Treatment

PurposeHigh-resolution pharyngeal manometry (HRPM) is an emerging technology that shows promise as both an adjuvant diagnostic and therapeutic tool in oropharyngeal dysphagia management. Advances in manometric technology, including increased number of sensors and topographical pressure plots, enhance the biofeedback potential for the pharynx. This clinical focus article serves as an overview of the utility of HRPM in dysphagia treatment.ConclusionHRPM-facilitated biofeedback aids the patient in the correct implementation of clinical recommendations and also provides the clinician an assessment of the effectiveness and accuracy of those targeted interventions. Topographic pressure plots provide intuitive feedback, allow easier swallow-to-swallow comparisons, and produce visually color-coded pressure information for the patient and clinician in real time. Paired with existing, evidence-based interventions, HRPM biofeedback may facilitate maneuver and strategy planning, exercise training and monitoring, temporal coordination, upper esophageal segment relaxation and duration, swallow mapping (topographic pattern recognition and approximation), fatigue monitoring, dose planning, adherence tracking, and efficacy assessment of selected interventions. Although competency training is needed to effectively utilize HRPM, there are growing opportunities for the speech-language pathologist to acquire and implement this technology for the benefit of patients.

Evaluation of Survival Rate and Non-Fetal Outcomes in Patients with Esophageal Cancer Under Treatment with Neoadjuvant Chemoradiotherapy Plus Additional Platinium-Based Chemotherapy from 2010 to 2016

Background: Esophageal cancer is an invasive lethal disease with a 10-year survival rate since diagnosis. About 45% of the tumor is completely removed by surgery, which has 5% mortality and 20% survival rate. In the locoregional stage, the use of neoadjuvant chemoradiotherapy and then surgery reduces recurrence and increases survival. Objectives: This study was performed to investigate the effect of neoadjuvant chemoradiotherapy and the subsequent chemotherapy with platinum-based regimen on survival, recurrence, and response to treatment. Methods: Planning a descriptive retrospective follow-up study, during 2010 to 2016, 44 patients with esophageal cancer, who received chemotherapy with 5-Fluorouracil + Oxaliplatin + Docetaxel before and after radiotherapy (45 - 50 Gray) accompanying by oral Capecitabin, were followed up. Five operable patients underwent surgery. Response to treatment and recurrence were evaluated by periodic endoscopic biopsy and imaging. To calculate the response rate to treatment, survival, and recurrence, the data were extracted and analyzed, using SPSS version 18. The categorized variables were compared, using Pearson’s test. The survival curves were drawn, using the Kaplan Meier method and compared with the log-rank test. Results: Among 44 patients with an average age of 61.5 ± 11.5 years, 88.6% had squamous cell carcinoma (SCC) and 11.4% had adenocarcinoma; surgery was performed for 5 patients, one of whom had severe complication leading to death and 54.5% had complete response as well as more survival rate. The patients suffering from SCC and middle segment tumors had more response rate. Also, recurrence was seen in 16 patients (36.4%), of whom 9.1% had local recurrence and 27.3% had metastatic recurrence. The mean survival rate was 38.87 months and 1-, 3-, and 5-year survival rate was %81.6, %47.6, and 39.6%, respectively. It was significantly more in middle esophageal segment and also tumors with complete response to treatment. Conclusions: Regarding the results, this treatment approach increases overall and disease-free survival, and response to treatment and reduces locoregional recurrence even if no surgery is performed. This treatment is recommended as a definitive treatment for esophageal cancer without metastasis.

HISTOLOGICAL EXAMINATION OF THE ELONGATED ESOPHAGUS IN EXPERIMENT

Introduction. Traction and convergence of atreseal ends of the esophagus with subsequent anastomosis is the most common technique for treating newborns with the fistulous form of esophagus atresia. The performed literature analysis did not reveal any researches aiming to study the correlation between a postoperative histological picture and diastasis length between atresial esophageal ends. Purpose. To assess the potential for modeling esophageal surgeries with biological models; to study and analyze the histological picture of operated esophagus and its correlation with the diastasis distance between atresial ends. Material and methods. Rats were randomly divided into three groups (n = 5 in each group). Rats from Group 1 had a standard surgery with the end-to-end esophageal anastomosis and artificially created diastasis of 1.0 cm by esophageal segment resection. Rats from Group 2 had a similar surgery but without any esophageal segment resection; so, the anastomosis in them was put without diastasis and significant tension of esophageal ends. Rats from Group 3 did not have any surgery; they were controls. The experimental rats were monitored daily for seven postoperative days. Results. There was no any significant macroscopic difference in the esophagus length in traction, nontraction and control groups. However, microscopic examination revealed that mucous and muscular membranes thickness in the esophagus, as a rule, was slightly thinner in the traction group. Despite the muscle layer thinning, hypertrophy of muscle fibers, lymphoplasmacytic infiltration with some eosinophilic leukocytes as well as signs of perifocal epitheliotropism were noted.

Esophageal covered stent treatment for gastroesophageal cervical anastomotic fistula

Objective To investigate the effectiveness and safety of esophageal covered stent for the treatment of esophagogastric cervical anastomotic fistula. Methods Retrospective analysis of clinical and imaging data of patients with esophageal and gastric anastomotic neck fistula treated by esophageal membrane stent implantation in the Affiliated Tumor Hospital of Zhengzhou University from July 2015 to June 2018. Twenty-one cases, 15 males and 6 females were enrolled. All patients showed fistula after esophagogastrostomy for esophageal carcinoma. All the fistulas were located in the cervical segment of esophagus and were diagnosed as anastomotic fistula 2 to 13 days after surgery. The length of esophagus residue, the position and size of the fistula were measured by esophagography. We retrospectively analyzed the data of patients with cervical anastomotic fistula treated with esophageal covered stent. Patients were followed up for more than 6 months by review and telephone follow-up. Results In the 21 patients, 19 (90.5%) were successfully implanted stents at one time, and 2 (9.5%) were placed at a lower position. The esophageal stent was implanted for 10 to 60 days (31±19) days, and the stent was successfully removed after the fistula healed, with a procedure time of 6 to 23 minutes. No recurrence of fistula was found during follow-up. Four patients had anastomotic scar stenosis, and eating smoothly after balloon dilatation. Conclusion Esophageal covered stent implantation is a safe and effective technique for gastroesophageal cervical anastomotic fistula. Key words: Esophageal neoplasms; Anastomotic leak; Stents; Radiology, interventional

Predictors of dysplastic and neoplastic progression of Barrett’s esophagus

It is unknown why some cases of Barrett’s esophagus progress to invasive malignant disease rapidly while others do so more slowly or not at all. The aim of this study was to identify demographic and endoscopic factors that predict dysplastic and neoplastic progression in patients with Barrett’s esophagus. Patients with Barrett’s esophagus who were assessed in 2000–2010 were assessed for inclusion in this retrospective study. Demographic and endoscopic variables were collected from an endoscopy database and the medical chart. Dysplastic and neoplastic progression was examined by time-to-event analysis. We used Cox proportional hazard regression modelling and generalized estimating equation methods to identify variables that were most predictive of neoplastic progression. A total of 518 patients had Barrett’s esophagus confirmed by endoscopy and pathology and at least 2 surveillance visits. Longer Barrett’s esophagus segment (≥ 3 cm) (odds ratio [OR] 1.2, 95% confidence interval [CI] 1.1–1.3) and increased age (≥ 60 yr) (OR 3.5, 95% CI 1.7–7.4) were independent predictors of progression from nondysplasia to dysplastic or neoplastic grades. Presence of mucosal irregularities (OR 8.6, 95% CI 2.4–30.4) and increased age (OR 5.1, 95% CI 1.6–16.6) were independent predictors of progression from nondysplasia to high-grade dysplasia or adenocarcinoma. Increased age, longer Barrett’s segment and presence of mucosal irregularities were associated with increased risk of dysplastic and neoplastic progression. In addition to dysplasia, these factors may help stratify patients according to risk of neoplastic progression and be used to individualize surveillance. More prospective studies with larger samples are required to validate these results.

Esophageal Compliance Quantifies Epithelial Remodeling in Pediatric Patients With Eosinophilic Esophagitis.

The management of eosinophilic esophagitis (EoE) relies on the severity of esophageal eosinophilia, yet there is poor evidence of its prediction of esophageal fibrotic remodeling and subsequent complications such as dysphagia, food impactions, or strictures. Functional luminal imaging planimetry (FLIP) has had limited use in pediatric patients to evaluate esophageal tissue mechanics. We aimed to standardize the FLIP technique and to measure esophageal compliance in children with EoE in comparison to controls. Subjects were enrolled into a prospective observational study and had FLIP performed at the time of endoscopy. We calculated esophageal distensibility and compliance for the total and segmental esophagus independently (ie, proximal, middle, and distal esophageal segments). We evaluated esophageal biopsies for eosinophilia and epithelial remodeling, calculated endoscopy scores, and documented patient symptoms. We enrolled 11 EoE and 12 controls subjects, aged 5 to 18 years old. While EoE subjects had lower esophageal compliance (P = 0.004) than controls, the difference in distensibility did not reach significance (P = 0.151). Epithelial remodeling severity was more strongly correlated with compliance than with distensibility. Epithelial remodeling scores ≥2 had a significant association with lower compliance both segmentally and in the entire esophagus (P = 0.029), but not with distensibility. Compliance measures were more sensitive in detecting subjects with remodeling score ≥2 than distensibility (79% vs 64%). Compliance is a more sensitive measure of esophageal epithelial remodeling in children compared to distensibility, and a more appropriate measure of esophageal tissue mechanics. Standardized placement of the FLIP catheter is important to accurately assess esophageal compliance.

Covering the Cover

Covering the Cover

Regional variations in the number distribution of intrinsic myenteric neurons and coinnervated motor endplates on the striated muscles in the rat esophagus.

The roles of intrinsic neurons and the significance of the coinnervated striated muscles in the esophagus are unclear. We examined the number distribution of intrinsic neurons and coinnervated motor endplates on the striated muscles in the rat esophagus using immunohistochemistry to investigate whether these neurons and coinnervated striated muscles may be relevant to the local control of esophageal motility. The number of PGP9.5-positive neurons was higher in the cervical esophagus (segment 1) and gradually decreased toward the aboral, with a moderate increase in the abdominal (segment 5). This pattern was similar to that of NOS-positive neurons, while the number of ChAT-positive neurons decreased toward the aboral, but it was not significantly different among segments 3 to 5. The number of ChAT-positive motor endplates increased toward the aboral, with the highest number in segment 5. The proportion of coinnervated motor endplates was approximately 80% in segments 1 to 4, but approximately 66% in segment 5. NPY-IR was localized in some nerve terminals among the smooth muscles of the muscularis mucosa and some NOS- or ChAT-positive esophageal intrinsic neurons. ENK-8-IR was found in some NOS- or ChAT-positive intrinsic neurons, and nerve terminals surrounding intrinsic neurons in the esophagus, but not in motor neurons at the NA or DMV. This study suggests that regional variations in the number of intrinsic neurons and coinnervated striated muscles in the rat esophagus may be involved in local regulations of esophageal motility, and that the rat esophageal intrinsic neurons may contain, at least, motor neurons and interneurons.

Outcomes of laparoscopic sleeve gastrectomy by means of esophageal manometry and pH-metry, before and after surgery.

IntroductionGastroesophageal reflux is a major problem after sleeve gastrectomy. There is still insufficient understanding of how it occurs and whether it is due to the sphincter length, relaxation, or pressure differences.AimThis study evaluates the effect on the lower esophageal sphincter of the laparoscopic sleeve gastrectomy (LSG) technique applied in surgery in cases of morbid obesity using ambulatory 24-h pH monitoring (APM) and esophageal manometry (EM).Material and methodsA retrospective examination was carried out on the APM and EM tests performed preoperatively and postoperatively in cases of LSG. The parameters examined were the body mass index (BMI), amplitude pressure of the esophagus (AP), total length of the lower esophageal segment (LESL), resting pressure of the LES (LESP), residual pressure of the LES (LESR), relaxation time of the LES, intragastric pressure, and the DeMeester score.ResultsA total of 62 cases with available data were evaluated. A statistically significant difference was determined between the preoperative values and the 3-month postoperative values of BMI, LESP, and relaxation time of the LES. A statistically significant increase was determined in the DeMeester score, and the increase in the total number of reflux episodes longer than 5 min was found to be the most responsible for this increase. No significant difference was determined in the other parameters.ConclusionsThe LSG was found to cause a reduction in LESP, and an increase in acid reflux causing an extended relaxation time of the LES. This was confirmed by the increase seen in the DeMeester score.

Flap Reconstruction as Alternative Anastomosis Technique for the Surgery of Oesophageal Atresia with Distal Oesophagotracheal Fistula

The creation of a primary anastomosis in newborns with oesophageal atresia and distal oesophageotracheal fistula (EA-DF) is technically challenging, especially in small children. The goal is to approximate the fragile oesophageal ends without suture disruption and to minimize the mobilisation of the lower segment. We describe an alternative anastomosis technique aiming at reducing the tension on the first sutures at the posterior wall. EA-DF was corrected in 13 newborns either by open (n = 11) or thoracoscopic (n = 2) surgery using this technique. The anastomosis technique is based on creation of a dorsal flap of the upper oesophageal pouch and insertion in the spatulated lower oesophageal segment after the fistula has been separated. Subsequently, the first sutures of the posterior wall can be accomplished with reduced tension. Upon completion of the anastomosis, a diagonally shaped anastomotic plane results. The method is a helpful alternative to approximate the oesophageal stumps of newborns with EA and distal oesophagotracheal fistula. By this technique, the first stabilising sutures of the posterior wall can be accomplished with reduced tension. This results in reduced tensile stress on the individual sutures and simplifies the anastomisation in comparison to the conventional end-to-end anastomosis.

ATP-dependent potassium channels contribute to motor regulation of esophageal striated muscle in rats

The aim of the present study was to clarify roles of ATP-dependent potassium channels (KATP channels) in motility of the striated muscle portion in the esophagus. An isolated segment of the rat esophagus was placed in an organ bath and mechanical responses were recorded using a force transducer. Electrical stimulation of the vagus nerve evoked contractile response of striated muscle in the esophageal segment. Application of glibenclamide, an antagonist of KATP channels, increased amplitude of vagally mediated twitch contractions of the rat esophagus. On the other hand, minoxidil, an agonist of KATP channels, decreased amplitude of twitch contractions. RT-PCR revealed the expression of subunits of KATP channels in esophageal tissue. In addition, immunopositivity for subunits of KATP channels was observed in the striated muscle cells of the esophageal muscle layer. These findings indicate that KATP channels contribute to motor regulation of striated muscle in the rat esophagus.

Value of Multidetector Computed Tomography in the Assessment of Achalasia Subtypes and Detection of Pulmonary and Thoracic Complications

Objective: To evaluate multidetector computed tomography (MDCT) findings in patients with achalasia, to assess its role in differentiating subtypes in detecting lung involvement and extra-esophageal thoracic complications. Subjects and Methods: This clinical retrospective study included 51 patients with manometrically confirmed achalasia who underwent chest X-ray and MDCT in diagnostic work-up. Esophageal wall thickness and morphology, luminal dilatation, lung changes, and extra-esophageal manifestations were analyzed on MDCT by 2 readers. Wilcoxon, Kruskal-Wallis and Mann-Whitney test were used for assessing the differences among the achalasia subtypes, and intra-class correlation coefficients (ICC) assessing the inter-observer agreement between the measurements of 2 readers. Results: Fourteen (27.5%) patients had achalasia subtype I, 21 (60.8%) had subtype II while 6 (11.8%) had subtype III. Esophageal wall thickness of the esophageal body (EB) and distal esophageal segment (DES) as well as nodular/lobulated appearance of DES were found significantly more often in subtype III (p = 0.024, p < 0.001, p = 0.009, respectively). Esophageal dilatation gradually decreased from subtype I to III (p = 0.006). Chest X-ray revealed lung changes in 9 (17%) and MDCT in 21 (41%) patients (p = 0.001), most frequently in subtype I, with predominance of ground-glass opacities. Tracheal/carinal compression was detected in 27 (52.9%) and left atrial compression in 17 (33.3%) patients. Excellent inter-observer agreement was observed in measuring the EB and DES wall thickness, and diameter of EB (ICC 0.829, 0.901, and 0.922). Conclusion: MDCT is a useful tool for detecting lung and extra-esophageal thoracic complications in patients with achalasia, and could be a valuable additional imaging modality in the differentiation of achalasia subtypes.

GENERAL ANATOMICAL CHARACTERISTICS OF SMALL INTESTINE IN WHITE RATS

Introduction. The structure of the small intestine in humans and white rats are quite similar. The study of its specific features in white rats is important to supplement and update modern morphological science with data on the course and modelling of certain pathological conditions. Purpose. A detailed study of the anatomical features of the small intestine in white rats is a prerequisite for planning and conducting certain experimental studies. Material and methods. The study was performed on 80 white male rats. The material for the study included removed stomachs with the distal segment of oesophagus, the small and large intestine. Following the removal the organs were fixed with 10% neutral formalin, outer and inner (mucosal) surfaces then were photographed. In other cases, the gastrointestinal tract of animals was filled through the oesophagus with air, physiological saline, and autopolymer plastic (Latacryl-S), and then exposed to acid corrosion, obtaining three-dimensional casts of internal cavities of the stomach, small and large intestine. Results. Having studying the anatomical features of the small intestine of white rats we can distinguish two parts: the initial extra mesenteric part, which can be called the duodenum only by analogy with a similar human section, and its other mesenteric part, in the looped segment of which the border between which the ileal and jejunum division was not found. This segment seems to be designed mainly for the transitive movement of food into the cecum, where their final processing and the formation of faecal masses occur. On the outer surface of the mesenteric small intestine, there are clearly visible groups of lymphoid nodules, known as Peyer's patches.