New technologies in the gastrointestinal clinic and research: Impedance and high-resolution manometry

The last five years have been an exciting time in the study of esophageal motor disorders due to the recent advances in esophageal function testing. New technologies have emerged, such as intraluminal impedance, while conventional techniques, such as manometry, have enjoyed many improvements due to advances in transducer technology, computerization and graphic data presentation. While these techniques provide more detailed information regarding esophageal function, our understanding of whether they can improve our ability to diagnose and treat patients more effectively is evolving. These techniques are also excellent research tools and they have added substantially to our understanding of esophageal motor function in dysphagia. This review describes the potential benefits that these new technologies may have over conventional techniques for the evaluation of dysphagia.

Anorectal dysfunction in patients with mid-low rectal cancer after surgery: A pilot study with three-dimensional high-resolution manometry

BACKGROUND The quality of life in patients who develop low anterior resection syndrome(LARS)after surgery for mid-low rectal cancer is seriously impaired.The underlying pathophysiological mechanism of LARS has not been fully investigated.AIM To assess anorectal function of mid-low rectal cancer patients developing LARS perioperatively.METHODS Patients diagnosed with mid-low rectal cancer were included.The LARS score was used to evaluate defecation symptoms 3 and 6 mo after anterior resection or a stoma reversal procedure.Anorectal functions were assessed by threedimensional high resolution anorectal manometry preoperatively and 3-6 mo after surgery.RESULTS The study population consisted of 24 patients.The total LARS score was decreased at 6 mo compared with 3 mo after surgery(P<0.05),but 58.3%(14/24)lasted as major LARS at 6 mo after surgery.The length of the high-pressure zone of the anal sphincter was significantly shorter,the mean resting pressure and maximal squeeze pressure of the anus were significantly lower than those before surgery in allpatients (P < 0.05), especially in the neoadjuvant therapy group after surgery (n = 18). The focalpressure defects of the anal canal were detected in 70.8% of patients, and those patients had higherLARS scores at 3 mo postoperatively than those without focal pressure defects (P < 0.05). Spasticperistaltic contractions from the new rectum to anus were detected in 45.8% of patients, whichwere associated with a higher LARS score at 3 mo postoperatively (P < 0.05).CONCLUSIONThe LARS score decreases over time after surgery in the majority of patients with mid-low rectalcancer. Anorectal dysfunctions, especially focal pressure defects of the anal canal and spasticperistaltic contractions from the new rectum to anus postoperatively, might be the majorpathophysiological mechanisms of LARS.

Distal esophageal spasm:Update on diagnosis and management in the era of high-resolution manometry

Distal esophageal spasm (DES) is a rare major motility disorder in the Chicago dassification of esophageal motility disorders (CC).DES is diagnosed by finding of≥20%premature contractions,with normal lower esophageal sphincter (LES)relaxation on high-resolution manometry (HRM) in the latest version of CCv3.0.This feature differentiates it from achalasia type 3,which has an elevated LES relaxation pressure.Like other spastic esophageal disorders,DES has been linked to conditions such as gastroesophageal reflux disease,psychiatric conditions,and narcotic use.In addition to HRM,ancillary tests such as endoscopy and barium esophagram can provide supplemental information to differentiate DES from other conditions.Functional lumen imaging probe (FLIP),a new cutting-edge diagnostic tool,is able to recognize abnormal LES dysfunction that can be missed by HRM and can further guide LES targeted treatment when esophagogastric junction outflow obstruction is diagnosed on FLIP.Medical treatment in DES mostly targets symptomatic relief and often fails.Botulinum toxin injection during endoscopy may provide a temporary therapy that wears off over time.Myotomy through peroral endoscopic myotomy or via surgical Heller myotomy can provide long term relief in cases with persistent symptoms.

Preoperative physiological esophageal assessment for anti-reflux surgery:A guide for surgeons on high-resolution manometry and pH testing

Gastroesophageal reflux disease (GERD) is one of the most commonlyencountered digestive diseases in the world, with the prevalence continuing toincrease. Many patients are successfully treated with lifestyle modifications andproton pump inhibitor therapy, but a subset of patients require more aggressiveintervention for control of their symptoms. Surgical treatment with fundoplicationis a viable option for patients with GERD, as it attempts to improve the integrityof the lower esophageal sphincter (LES). While surgery can be as effective asmedical treatment, it can also be associated with side effects such as dysphagia,bloating, and abdominal pain. Therefore, a thorough pre-operative assessment iscrucial to select appropriate surgical candidates. Newer technologies arebecoming increasingly available to help clinicians identify patients with true LESdysfunction, such as pH-impedance studies and high-resolution manometry(HRM). Pre-operative evaluation should be aimed at confirming the diagnosis ofGERD, ruling out any major motility disorders, and selecting appropriate surgicalcandidates. HRM and pH testing are key tests to consider for patients with GERDlike symptoms, and the addition of provocative measures such as straight legraises and multiple rapid swallows to HRM protocol can assess the presence ofunderlying hiatal hernias and to test a patient’s peristaltic reserve prior tosurgery.

High-resolution colonic manometry and its clinical application in patients with colonic dysmotility: A review

The detailed process and mechanism of colonic motility are still unclear, and colonic motility disorders are associated with numerous clinical diseases. Colonic manometry is considered to the most direct means of evaluating colonic peristalsis. Colonic manometry has been studied for more than 30 years;however, the long duration of the examination, high risk of catheterization, huge amount of real-time data, strict catheter sterilization, and high cost of disposable equipment restrict its wide application in clinical practice. Recently, highresolution colonic manometry (HRCM) has rapidly developed into a major technique for obtaining more effective information involved in the physiology and/or pathophysiology of colonic contractile activity in colonic dysmotility patients. This review focuses on colonic motility, manometry, operation, and motor patterns, and the clinical application of HRCM. Furthermore, the limitations, future directions, and potential usefulness of HRCM in the evaluation of clinical treatment effects are also discussed.

Verification and Validation of High-Resolution Inviscid and Viscous Conical Nozzle Flows

Capturing elaborated flow structures and phenomena is required for well-solved numerical flows.The finite difference methods allow simple discretization of mesh and model equations.However,they need simpler meshes,e.g.,rectangular.The inverse Lax-Wendroff(ILW)procedure can handle complex geometries for rectangular meshes.High-resolution and high-order methods can capture elaborated flow structures and phenomena.They also have strong mathematical and physical backgrounds,such as positivity-preserving,jump conditions,and wave propagation concepts.We perceive an effort toward direct numerical simulation,for instance,regarding weighted essentially non-oscillatory(WENO)schemes.Thus,we propose to solve a challenging engineering application without turbulence models.We aim to verify and validate recent high-resolution and high-order methods.To check the solver accuracy,we solved vortex and Couette flows.Then,we solved inviscid and viscous nozzle flows for a conical profile.We employed the finite difference method,positivity-preserving Lax-Friedrichs splitting,high-resolution viscous terms discretization,fifth-order multi-resolution WENO,ILW,and third-order strong stability preserving Runge-Kutta.We showed the solver is high-order and captured elaborated flow structures and phenomena.One can see oblique shocks in both nozzle flows.In the viscous flow,we also captured a free-shock separation,recirculation,entrainment region,Mach disk,and the diamond-shaped pattern of nozzle flows.

A High-Resolution Measurement Method for Inner and Outer 3D Surface Profiles of Laser Fusion Targets Using a Laser Differential Confocal–Atomic Force Probe Technique

The high-resolution and nondestructive co-reference measurement of the inner and outer threedimensional(3D)surface profiles of laser fusion targets is difficult to achieve.In this study,we propose a laser differential confocal(LDC)–atomic force probe(AFP)method to measure the inner and outer 3D surface profiles of laser fusion targets at a high resolution.This method utilizes the LDC method to detect the deflection of the AFP and exploits the high spatial resolution of the AFP to enhance the spatial resolution of the outer profile measurement.Nondestructive and co-reference measurements of the inner profile of a target were achieved using the tomographic characteristics of the LDC method.Furthermore,by combining multiple repositionings of the target using a horizontal slewing shaft,the inner and outer 3D surface profiles of the target were obtained,along with a power spectrum assessment of the entire surface.The experimental results revealed that the respective axial and lateral resolutions of the outer profile measurement were 0.5 and 1.3 nm,while the respective axial and lateral resolutions of the inner profile measurement were 2.0 nm and approximately 400.0 nm.The repeatabilities of the rootmean-square deviation measurements for the outer and inner profiles of the target were 2.6 and 2.4 nm,respectively.We believe our study provides a promising method for the high-resolution and nondestructive co-reference measurement of the inner and outer 3D profiles of laser fusion targets.

Accurate Source-Receiver Positioning Method for a High-Resolution Deep-Towed Multichannel Seismic Exploration System

The near-seabed multichannel seismic exploration systems have yielded remarkable successes in marine geological disaster assessment,marine gas hydrate investigation,and deep-sea mineral exploration owing to their high vertical and horizontal resolution.However,the quality of deep-towed seismic imaging hinges on accurate source-receiver positioning information.In light of existing technical problems,we propose a novel array geometry inversion method tailored for high-resolution deep-towed multichannel seismic exploration systems.This method is independent of the attitude and depth sensors along a deep-towed seismic streamer,accounting for variations in seawater velocity and seabed slope angle.Our approach decomposes the towed line array into multiline segments and characterizes its geometric shape using the line segment distance and pitch angle.Introducing optimization parameters for seawater velocity and seabed slope angle,we establish an objective function based on the model,yielding results that align with objective reality.Employing the particle swarm optimization algorithm enables synchronous acquisition of optimized inversion results for array geometry and seawater velocity.Experimental validation using theoretical models and practical data verifies that our approach effectively enhances source and receiver positioning inversion accuracy.The algorithm exhibits robust stability and reliability,addressing uncertainties in seismic traveltime picking and complex seabed topography conditions.

Investigating the relationship between intracranial atherosclerotic plaque remodelling and diabetes using high-resolution vessel wall imaging

BACKGROUND Intracranial atherosclerosis,a leading cause of stroke,involves arterial plaque formation.This study explores the link between plaque remodelling patterns and diabetes using high-resolution vessel wall imaging(HR-VWI).AIM To investigate the factors of intracranial atherosclerotic remodelling patterns and the relationship between intracranial atherosclerotic remodelling and diabetes mellitus using HR-VWI.METHODS Ninety-four patients diagnosed with middle cerebral artery or basilar artery INTRODUCTION Intracranial atherosclerotic disease is one of the main causes of ischaemic stroke in the world,accounting for approx-imately 10%of transient ischaemic attacks and 30%-50%of ischaemic strokes[1].It is the most common factor among Asian people[2].The adaptive changes in the structure and function of blood vessels that can adapt to changes in the internal and external environment are called vascular remodelling,which is a common and important pathological mechanism in atherosclerotic diseases,and the remodelling mode of atherosclerotic plaques is closely related to the occurrence of stroke.Positive remodelling(PR)is an outwards compensatory remodelling where the arterial wall grows outwards in an attempt to maintain a constant lumen diameter.For a long time,it was believed that the degree of stenosis can accurately reflect the risk of ischaemic stroke[3-5].Previous studies have revealed that lesions without significant luminal stenosis can also lead to acute events[6,7],as summarized in a recent meta-analysis study in which approximately 50%of acute/subacute ischaemic events were due to this type of lesion[6].Research[8,9]has pointed out that the PR of plaques is more dangerous and more likely to cause acute ischaemic stroke.Previous studies[10-13]have found that there are specific vascular remodelling phenomena in the coronary and carotid arteries of diabetic patients.However,due to the deep location and small lumen of intracranial arteries and limitations of imaging techniques,the relationship between intracranial arterial remodelling and diabetes is still unclear.In recent years,with the development of magnetic resonance technology and the emergence of high-resolution(HR)vascular wall imaging,a clear and multidimensional display of the intracranial vascular wall has been achieved.Therefore,in this study,HR wall imaging(HR-VWI)was used to display the remodelling characteristics of bilateral middle cerebral arteries and basilar arteries and to explore the factors of intracranial vascular remodelling and its relationship with diabetes.

In vivo pilot study into superficial microcirculatory characteristics of colorectal adenomas using novel high-resolution magnifying endoscopy with blue laser imaging

BACKGROUND No studies have yet been conducted on changes in microcirculatory hemody-namics of colorectal adenomas in vivo under endoscopy.The microcirculation of the colorectal adenoma could be observed in vivo by a novel high-resolution magnification endoscopy with blue laser imaging(BLI),thus providing a new insight into the microcirculation of early colon tumors.AIM To observe the superficial microcirculation of colorectal adenomas using the novel magnifying colonoscope with BLI and quantitatively analyzed the changes in hemodynamic parameters.METHODS From October 2019 to January 2020,11 patients were screened for colon adenomas with the novel high-resolution magnification endoscope with BLI.Video images were recorded and processed with Adobe Premiere,Adobe Photoshop and Image-pro Plus software.Four microcirculation parameters:Microcirculation vessel density(MVD),mean vessel width(MVW)with width standard deviation(WSD),and blood flow velocity(BFV),were calculated for adenomas and the surrounding normal mucosa.RESULTS A total of 16 adenomas were identified.Compared with the normal surrounding mucosa,the superficial vessel density in the adenomas was decreased(MVD:0.95±0.18 vs 1.17±0.28μm/μm2,P<0.05).MVW(5.11±1.19 vs 4.16±0.76μm,P<0.05)and WSD(11.94±3.44 vs 9.04±3.74,P<0.05)were both increased.BFV slowed in the adenomas(709.74±213.28 vs 1256.51±383.31μm/s,P<0.05).CONCLUSION The novel high-resolution magnification endoscope with BLI can be used for in vivo study of adenoma superficial microcirculation.Superficial vessel density was decreased,more irregular,with slower blood flow.

High-resolution magnetic resonance imaging in the diagnosis and management of vertebral artery dissection:A case report

BACKGROUND Vertebral artery dissection(VAD)is a rare but life-threatening condition characterized by tearing of the intimal layer of the vertebral artery,leading to stenosis,occlusion or rupture.The clinical presentation of VAD can be heterogeneous,with common symptoms including headache,dizziness and balance problems.Timely diagnosis and treatment are crucial for favorable outcomes;however,VAD is often missed due to its variable clinical presentation and lack of robust diagnostic guidelines.High-resolution magnetic resonance imaging(HRMRI)has emerged as a reliable diagnostic tool for VAD,providing detailed visualization of vessel wall abnormalities.CASE SUMMARY A young male patient presented with an acute onset of severe headache,vomiting,and seizures,followed by altered consciousness.Imaging studies revealed bilateral VAD,basilar artery thrombosis,multiple brainstem and cerebellar infarcts,and subarachnoid hemorrhage.Digital subtraction angiography(DSA)revealed vertebral artery stenosis but failed to detect the dissection,potentially because intramural thrombosis obscured the VAD.In contrast,HRMRI confirmed the diagnosis by revealing specific signs of dissection.The patient was managed conservatively with antiplatelet therapy and other supportive measures,such as blood pressure control and pain management.After 5 mo of rehabilitation,the patient showed significant improvement in swallowing and limb strength.CONCLUSION HR-MRI can provide precise evidence for the identification of VAD.

Upper esophageal sphincter abnormalities on high-resolution esophageal manometry and treatment response of type Ⅱ achalasia

BACKGROUND Little is known about the clinical significance of upper esophageal sphincter(UES)motility disorders and their association with the treatment response of typeⅡachalasia.None of the three versions of the Chicago Classification of Esophageal Motility Disorders has defined UES abnormality metrics or their function.UES abnormalities exist in some patients and indicate a clinically significant problem in patients with achalasia.AIM To demonstrate the manometric differentiation on high-resolution esophageal manometry between subjects with abnormal UES and normal UES,and the association between UES type and the treatment response of typeⅡachalasia.METHODS In total,498 consecutive patients referred for high-resolution esophageal manometry were analyzed retrospectively.The patients were divided into two groups,those with normal and abnormal UES function.UES parameters were analyzed after determining lower esophageal sphincter(LES)function.Patients with typeⅡachalasia underwent pneumatic dilation for treatment.Using mixed model analyses,correlations between abnormal UES and treatment response were calculated among subjects with typeⅡachalasia.RESULTS Of the 498 consecutive patients,246(49.40%)were found to have UES abnormalities.Impaired relaxation alone was the most common UES abnormality(52.85%,n=130).The incidence rate of typeⅡachalasia was significantly higher in subjects with abnormal UES than those with normal UES(9.77%vs 2.58%,P=0.01).After pneumatic dilation,LES resting pressure,LES integrated relaxation pressure,and UES residual pressure were significantly decreased(41.91±9.20 vs 26.18±13.08,38.94±10.28 vs 16.71±5.65,and 11.18±7.93 vs 5.35±4.77,respectively,P<0.05).According to the Eckardt score,subjects with typeⅡachalasia and abnormal UES presented a significantly poorer treatment response than those with normal UES(83.33%vs 0.00%,P<0.05).CONCLUSION Impaired relaxation alone is the most common UES abnormality.The incidence of typeⅡachalasia is associated with abnormal UES.TypeⅡachalasia with abnormal UES has a poorer treatment response,which is a potentially prognostic indicator of treatment for this disease.

Semi-Solid and Solid Bolus Swallows in High-Resolution Oesophageal Manometry for the Detection of Motility Disorders

Background/Aims: High-resolution oesophageal manometry utilises water swallows to evaluate oesophageal function. However, small volumes of water are not representative of normal eating and as a result often produce normal manometry studies in patients with dysphagia. This study sets out to establish optimal diagnostic thresholds for semi-solid solid swallows and evaluate their ability to uncover motility abnormalities in patients with motility disorders. Method: Manometry was performed using ten 5-mL single water swallows followed by two semi-solid and two solid swallows in the upright position. Normative values for the adjunctive tests were obtained from patient controls while patients with major motility disorders were used to establish the optimal diagnostic thresholds. Diagnostic thresholds identified were prospectively tested in patients with normal water swallows but oesophagus related symptoms and in those with minor and major motility disorders. Results: Normal values for semi-solid and solid were determined in patient controls (n = 100). Development of diagnostic thresholds included 120 patients with major motility disorders. Optimal diagnostic thresholds identified for oesophagogastric junction dysfunction in semi-solid and solid swallows (IRP > 15.5 mmHg). Hypercontractilty and spasm used existing thresholds (>8000 mmHg-s-cm and < 4.5 s, respectively) but modified frequency of ≥50% of adjunctive swallows. Diagnostic thresholds were applied to symptomatic patients with normal water swallows (n = 70) identifying 12/70 (17%) to have abnormal adjunctive swallows. One of 30 patients (3%) with ineffective motility had abnormal adjunctive swallow and 12 patients with oesophageal spasm, oesophagogastric junction obstruction, and hypercontractility had abnormal adjunctive swallows that moved them up the motility disorder hierarchy. Conclusions: Semi-solid and solid challenge increase diagnostic yield of motility disorders.

High-Resolution Esophageal Manometry in Teenagers with Esophageal Atresia

Introduction: Children with surgically repaired esophageal atresia (EA) show esophageal dysmotility. Due to the performance of high-resolution manometry (HRM), three motility alteration patterns have been described, which allowed to know the segmental alterations. Objective: To describe the esophageal motility patterns found through HRM in teenagers with EA and to relate these with the associated esophageal pathology and its severity. Materials and Method: Ten teenagers were included with no history of esophageal blockage or dilations in the last six months, who were orally fed and asymptomatic. Through performance of HRM, we found surgical and endoscopic history, as well as of esophageal biopsies and pH monitoring. Results: We found the following patterns: aperistalsis, pressurization and distal contraction. 70% showed distal contraction, and 100% of esophageal endoscopies and biopsies were normal. 57% of the esophageal pH monitoring analyzed was pathologic. In the pressurization and aperistalsis groups, we observed severe esophagitis and requirement of Nissen antireflux procedure in 100% of the cases. Esophageal pH monitoring analyzed was 100% pathologic. Conclusion: We described the esophageal segmental alterations in teenagers with atresia by means of HRM. The distal contraction group showed better development, without severe esophagitis or requirement of antireflux procedure. Therefore, by performing an HRM in teenagers with EA, we could predict the future esophageal behavior, according to the peristaltic pattern, since there are significant differences among the groups in study.

High-resolution seismic inversion method based on joint data-driven in the time-frequency domain

Seismic inversion can be divided into time-domain inversion and frequency-domain inversion based on different transform domains.Time-domain inversion has stronger stability and noise resistance compared to frequencydomain inversion.Frequency domain inversion has stronger ability to identify small-scale bodies and higher inversion resolution.Therefore,the research on the joint inversion method in the time-frequency domain is of great significance for improving the inversion resolution,stability,and noise resistance.The introduction of prior information constraints can effectively reduce ambiguity in the inversion process.However,the existing modeldriven time-frequency joint inversion assumes a specific prior distribution of the reservoir.These methods do not consider the original features of the data and are difficult to describe the relationship between time-domain features and frequency-domain features.Therefore,this paper proposes a high-resolution seismic inversion method based on joint data-driven in the time-frequency domain.The method is based on the impedance and reflectivity samples from logging,using joint dictionary learning to obtain adaptive feature information of the reservoir,and using sparse coefficients to capture the intrinsic relationship between impedance and reflectivity.The optimization result of the inversion is achieved through the regularization term of the joint dictionary sparse representation.We have finally achieved an inversion method that combines constraints on time-domain features and frequency features.By testing the model data and field data,the method has higher resolution in the inversion results and good noise resistance.

OPTIMIZATION OF WEIGHTED HIGH-RESOLUTION RANGE PROFILE FOR RADAR TARGET RECOGNITION

For the recognition of high-resolution range profile （HRRP） in radar, the weighted HRRP can reduce the instability of range cells caused by the attitude change of targets. A novel approach is proposed to optimize the weighted HRRP. In the approach, the separability of weighted HRRPs in different targets is measured by de- signing an objective function, and the weighted coefficients are computed by using the gradient descent method, thus enhancing the influence of stable range cells. Simulation results based on five aircraft models show that the approach can effectively optimize the weighted HRRP and improve the recognition accuracy.

Projection of Future Precipitation Change over China with a High-Resolution Global Atmospheric Model

Projections of future precipitation change over China are studied based on the output of a global AGCM, ECHAM5, with a high resolution of T319 （equivalent to 40 km）. Evaluation of the model’s performance in simulating present-day precipitation shows encouraging results. The spatial distributions of both mean and extreme precipitation, especially the locations of main precipitation centers, are reproduced reasonably. The simulated annual cycle of precipitation is close to the observed. The performance of the model over eastern China is generally better than that over western China. A weakness of the model is the overestimation of precipitation over northern and western China. Analyses on the potential change in precipitation projected under the A1B scenario show that both annual mean precipitation intensity and extreme precipitation would increase significantly over southeastern China. The percentage increase in extreme precipitation is larger than that of mean precipitation. Meanwhile, decreases in mean and extreme precipitation are evident over the southern Tibetan Plateau. For precipitation days, extreme precipitation days are projected to increase over all of China. Both consecutive dry days over northern China and consecutive wet days over southern China would decrease.

High-resolution remote sensing image-based extensive deformation-induced landslide displacement field monitoring method

Landslide is one of the multitudinous serious geological hazards. The key to its control and reduction lies on dynamic monitoring and early warning. The article points out the insufficiency of traditional measuring means applied for large-scale landslide monitoring and proposes the method for extensive landslide displacement field monitoring using high- resolution remote images. Matching of cognominal points is realized by using the invariant features of SIFT algorithm in image translation, rotation, zooming, and affine transformation, and through recognition and comparison of characteristics of high-resolution images in different landsliding periods. Following that, landslide displacement vector field can be made known by measuring the distances and directions between cognominal points. As evidenced by field application of the method for landslide monitoring at West Open Mine in Fushun city of China, the method has the attraction of being able to make areal measurement through satellite observation and capable of obtaining at the same time the information of large- area intensive displacement field, for facilitating automatic delimitation of extent of landslide displacement vector field and sliding mass. This can serve as a basis for making analysis of laws governing occurrence of landslide and adoption of countermeasures.

Computational Performance of the High-Resolution Atmospheric Model FAMIL

This paper describes the model speed and model In/Out （I/O） efficiency of the high-resolution atmospheric general circulation model FAMIL （Finite- volume Atmospheric Model of IAP/LASG） at the National Supercomputer Center in Tianjin, China, on its Tianhe-lA supercomputer platform. A series of three- model-day simulations were carried out with standard Aqua Planet Experiment （APE） designed within FAMIL to obtain the time stamp for the calculation of model speed, simulation cost, and model 1/O efficiency. The results of the simulation demonstrate that FAMIL has remarkable scalability below 3456 and 6144 cores, and the lowest simulation costs are 1536 and 3456 cores for 12.5 km and 6.25 krn resolutions, respectively. Furthermore, FAMIL has excellent I/O scalability and an efficiency of more than 80% on 6 I/Os and more than 99% on 1536 I/Os.

Diagnostic value of high-resolution micro-endoscopy for theclassification of colon polyps

AIM: To study a new imaging equipment, highresolution micro-endoscopy(HRME), in the diagnosis and pathological classification of colon polyps.METHODS: We selected 114 specimens of colon polyps, 30 of which were colon polyps with known pathological types and 84 that were prospective polyp specimens; 10 normal colon mucosa specimens served as controls. We obtained images of 30 colon polyp specimens with known pathological types using HRME and analyzed the characteristics of these images to develop HRME diagnostic criteria for different pathological types of colon polyps. Based on these criteria, we performed a prospective study of 84 colon polyp specimens using HRME and compared the results with those of the pathological examination to evaluate the diagnostic value of HRME in the pathological classification of different types of colon polyps. RESULTS: In the 30 cases of known pathological type of colon polyp samples, there were 21 cases of adenomatous polyps, which comprised nine cases of tubular adenoma, seven cases of villous adenoma and five cases of mixed adenomas. The nine cases of non-adenomatous polyps included four cases of inflammatory polyps and five cases of hyperplastic polyps five. Ten cases of normal colonic mucosa were confirmed pathologically. In a prospective study of 84 cases using HRME, 23 cases were diagnosed as inflammatory polyps, 11 cases as hyperplastic polyps, 18 cases as tubular adenoma, eight cases as villous adenoma and 24 cases as mixed adenomas. After pathological examination, 24 cases were diagnosed as inflammatory polyps, 11 cases as hyperplastic polyps, 19 cases as tubular adenoma, eight cases as villous adenoma and 22 cases as mixed adenomas. Compared with the pathological examinations, the sensitivities, specificities, accuracies, and positive and negative predictive values of HRME in diagnosing inflammatory polyps(87.5%, 96.7%, 94.0%, 91.3% and 95.1%), hyperplastic polyps(72.7%, 95.9%, 92.9%, 72.7% and 95.9%), tubular adenomas(73.7%, 93.8%, 89.3%, 77.8% and 92.4%), villous adenomas(75.0%, 97.4%, 95.2%, 75.0% and 97.4%), and mixed adenomas(75.0%, 93.3%, 88.1%, 81.8% and 90.3%) were relatively high.CONCLUSION: HRME has a relatively high diagnostic value in the pathological classification of colon polyps. Thus, it may be an alternative to confocal microendoscopy in lower-resource or community-based settings.