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1.
Inflamm Intest Dis ; 9(1): 147-156, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39015256

RESUMEN

Introduction: Crohn's disease (CD) of the small bowel is associated with a severe course and increased risk of complications. Strictures at this location are challenging to diagnose and out-of-reach of colonoscopy. We aimed to evaluate the detection rate of small bowel strictures with magnetic resonance enterography (MRE) and assess the efficacy of double balloon enteroscopy-assisted endoscopic balloon dilatation (DBE-assisted EBD) in managing these strictures. Methods: A retrospective study included all patients with DBE-assisted EBD of small bowel strictures in CD in our facility. All patients had MRE to detect strictures prior to the dilatation. Sequential dilatation protocol was performed using through-the-scope (TTS) working channel balloons. The outcomes included technical success defined by the passage of the enteroscope post-dilatation, resolution of symptoms, and the requirement of repeated procedures or surgery during 12 months of follow-up. Results: Twenty DBE-assisted EBDs of small bowel strictures were attempted during 13 DBE procedures in 10 patients (6 males, median age 42). MRE identified 75% of the strictures with 100% accuracy in localisation. Retrograde DBE was the approach in 16/20 (80%) strictures. Anaesthetic intubation was used in 8/20 (40%). DBE reached 19/20 strictures. All the reached strictures were dilated successfully; the technical success following dilatation was 72.2%. The median DBE insertion time with TTS balloon dilatation was 66 min. Three patients required follow-up dilatations within 2-3 months. Surgery was not needed during the follow-up period. Conclusions: MRE is essential in diagnosing and localising small bowel strictures in CD. DBE reached 95% of strictures with successful dilatation. Immediate technical success was high, and safety was demonstrated. Planned repeat procedures for sequential dilatation were performed in a few patients. Surgical resection was avoided in all patients.

2.
Int J Med Robot ; 17(4): e2224, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33426753

RESUMEN

BACKGROUND AND AIM: Most of the mixed reality models used in the surgical telepresence are suffering from the discrepancies in the boundary area and spatial-temporal inconsistency due to the illumination variation in the video frames. The aim behind this work is to propose a new solution that helps produce the composite video by merging the augmented video of the surgery site and virtual hand of the remote expertise surgeon. The purpose of the proposed solution is to decrease the processing time and enhance the accuracy of merged video by decreasing the overlay and visualization error and removing occlusion and artefacts. METHODOLOGY: The proposed system enhanced mean-value cloning algorithm that helps to maintain the spatial-temporal consistency of the final composite video. The enhanced algorithm includes the three-dimensional mean-value coordinates and improvised mean-value interpolant in the image cloning process, which helps to reduce the sawtooth, smudging and discolouration artefacts around the blending region. RESULTS: The accuracy in terms of overlay error of the proposed solution is improved from 1.01 to 0.80 mm, whereas the accuracy in terms of visualization error is improved from 98.8% to 99.4%. The processing time is reduced to 0.173 s from 0.211 s. The processing time and the accuracy of the proposed solution are enhanced as compared to the state-of-art solution. CONCLUSION: Our solution helps make the object of interest consistent with the light intensity of the target image by adding the space distance that helps maintain the spatial consistency in the final merged video.


Asunto(s)
Realidad Aumentada , Cirugía Asistida por Computador , Algoritmos , Clonación Molecular , Humanos , Imagenología Tridimensional , Interfaz Usuario-Computador
3.
Int J Med Robot ; : e2161, 2020 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-32886412

RESUMEN

BACKGROUND AND AIM: Most of the Mixed Reality models used in the surgical telepresence are suffering from the discrepancies in the boundary area and spatial-temporal inconsistency due to the illumination variation in the video frames. The aim behind this work is to propose a new solution that helps produce the composite video by merging the augmented video of the surgery site and virtual hand of the remote expertise surgeon. The purpose of the proposed solution is to decrease the processing time and enhance the accuracy of merged video by decreasing the overlay and visualization error and removing occlusion and artefacts. METHODOLOGY: The proposed system enhanced the mean value cloning algorithm that helps to maintain the spatial-temporal consistency of the final composite video. The enhanced algorithm includes the 3D mean value coordinates and improvised mean value interpolant in the image cloning process, which helps to reduce the sawtooth, smudging and discoloration artefacts around the blending region RESULTS: As compared to the state of art solution, the accuracy in terms of overlay error of the proposed solution is improved from 1.01mm to 0.80mm whereas the accuracy in terms of visualization error is improved from 98.8% to 99.4%. The processing time is reduced to 0.173 seconds from 0.211 seconds CONCLUSION: Our solution helps make the object of interest consistent with the light intensity of the target image by adding the space distance that helps maintain the spatial consistency in the final merged video. This article is protected by copyright. All rights reserved.

4.
Int J Med Robot ; 16(5): 1-22, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32388923

RESUMEN

BACKGROUND: Mixed reality (MR) visualization is gaining popularity in image-guided surgery (IGS) systems, especially for hard and soft tissue surgeries. However, a few MR systems are implemented in real time. Some factors are limiting MR technology and creating a difficulty in setting up and evaluating the MR system in real environments. Some of these factors include: the end users are not considered, the limitations in the operating room, and the medical images are not fully unified into the operating interventions. METHODOLOGY: The purpose of this article is to use Data, Visualization processing, and View (DVV) taxonomy to evaluate the current MR systems. DVV includes all the components required to be considered and validated for the MR used in hard and soft tissue surgeries. This taxonomy helps the developers and end users like researchers and surgeons to enhance MR system for the surgical field. RESULTS: We evaluated, validated, and verified the taxonomy based on system comparison, completeness, and acceptance criteria. Around 24 state-of-the-art solutions that are picked relate to MR visualization, which is then used to demonstrate and validate this taxonomy. The results showed that most of the findings are evaluated and others are validated. CONCLUSION: The DVV taxonomy acts as a great resource for MR visualization in IGS. State-of-the-art solutions are classified, evaluated, validated, and verified to elaborate the process of MR visualization during surgery. The DVV taxonomy provides the benefits to the end users and future improvements in MR.


Asunto(s)
Realidad Aumentada , Cirugía Asistida por Computador , Humanos
5.
Int J Med Robot ; 16(2): e2043, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31674715

RESUMEN

The purpose of this study is to replace the manual process (selecting the landmarks on mesh and anchor points on the video) by Intensity-based Automatic Registration method to reach registration accuracy and low processing time. The proposed system consists of an Enhanced Intensity-based Automatic Registration (EIbAR) using Modified Zero Normalized Cross Correlation (MZNCC) algorithm. The proposed system was implemented on videos of breast cancer tumors. Results showed that the proposed algorithm-as compared to a reference-improved registration accuracy by an average of 2 mm. In addition, the proposed algorithm-as compared to a reference-reduced the number of pixel matching, thereby reducing processing time on the video by an average of 22 ms/frame. The proposed system can, thus, provide an acceptable accuracy and processing time during scene augmentation of videos, which provides a seamless use of augmented-reality for surgeons in visualizing cancer tumors.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/cirugía , Procesamiento de Imagen Asistido por Computador/métodos , Imagenología Tridimensional/métodos , Cirugía Asistida por Computador/métodos , Algoritmos , Realidad Aumentada , Femenino , Humanos , Reconocimiento de Normas Patrones Automatizadas , Reproducibilidad de los Resultados , Tomografía Computarizada por Rayos X , Grabación en Video
6.
Int J Med Robot ; 16(2): e2055, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31702094

RESUMEN

BACKGROUND: Augmented reality (AR) is still a primarily theoretical concept in areas such as bowel, liver, gallbladder, and jaw surgeries because of the limitation of visualization accuracy of hidden organs and internal structures. This paper aims to improve the cutting accuracy, visualizing accuracy, and processing time of the augmented video. METHODOLOGY: The proposed system consists of an enhanced block-matching algorithm (BMA) with ghosting map technique. RESULTS: Results proved that proposed system reduced the visualization error, which ranges from 1.48 to 1.83 mm against the existing system visualization error 1.67 to 2.0. Similarly, the processing time also improved 59 to 72 ms/frame over the 50 to 58 ms/frame. CONCLUSION: This study showed the improvement and solved the problem soft tissue reconstruction and visualization on the AR video that used in bowel and gallbladder surgeries.


Asunto(s)
Realidad Aumentada , Procedimientos Quirúrgicos del Sistema Digestivo/instrumentación , Procedimientos Quirúrgicos del Sistema Digestivo/métodos , Algoritmos , Vesícula Biliar/cirugía , Humanos , Procesamiento de Imagen Asistido por Computador , Imagenología Tridimensional/métodos , Intestinos/cirugía , Laparoscopía/métodos , Hígado/cirugía , Fantasmas de Imagen , Reproducibilidad de los Resultados , Cirugía Asistida por Computador/métodos , Tomografía Computarizada por Rayos X , Interfaz Usuario-Computador , Grabación en Video
7.
Health Informatics J ; 26(1): 539-562, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-30973294

RESUMEN

Medical diagnosis through classification is often critical as the medical datasets are multilabel in nature, that is, a patient may have more than one health condition: high blood pressure, obesity, and diabetes. The aim of this article is to improve the accuracy and performance of multilabel classification using multilabel feature selection and improved overlapping clustering method. The proposed system consists of Optimized Initial Cluster Centers and Enhanced Objective Function technique to reduce the number of iterations in the clustering process thereby improving the clustering performance and to improve the clustering accuracy which will result in improving the accuracy and performance of multilabel classification. Ratios of clustering distance to class distance and execution time are used as the evaluation metric for accuracy and total execution time is used as the evaluation metric for performance. Based on the different combination with the number of labels, attributes, instances, and number of clusters, different values of accuracy and performance are obtained. The results on all 10 datasets show that the proposed technique is superior to the current technique. Furthermore, on average, the proposed technique has improved the classification accuracy by 5%-7%. Furthermore, the performance of new technique is improved by decreasing the processing time by 0.5-1 s on average. The proposed system targets on improving the accuracy and performance of the multilabel classification for medical diagnosis, which consists of multilabel feature selection and enhanced overlapping clustering technique. This study provides an acceptable range of accuracy with improved processing time, which assists the doctors in medical diagnosis (high blood pressure, obesity, and diabetes) of patients.


Asunto(s)
Análisis por Conglomerados , Algoritmos , Humanos
8.
Clin Gastroenterol Hepatol ; 13(8): 1453-63.e1, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25771246

RESUMEN

BACKGROUND & AIMS: The incidences of the inflammatory bowel diseases (IBDs) Crohn's disease (CD) and ulcerative colitis (UC) are increasing, indicating gene-environment interactions. Migrants from low-IBD-prevalence countries to a high-prevalence country may help identify the relative contribution of environmental risk factors compared with native Caucasians. METHODS: This prospective case-control study evaluated IBD environmental risk factors of Middle Eastern migrants (MEM) in Australia compared with matched Caucasian IBD subjects, MEM controls, Caucasian controls, and controls in the Middle East using adjusted odds ratios (aOR). RESULTS: A total of 795 subjects were recruited: 154 MEM cases (75 CD; 79 UC), 153 MEM controls, 162 Caucasian cases (85 CD; 77 UC), 173 Caucasian controls, and 153 controls in Lebanon. Smoking increased CD risk in MEM and Caucasians and reduced UC risk in Caucasians (aOR, 0.77; 95% CI, 0.41-0.98) but not MEM (aOR, 1.45; 95% CI, 0.80-2.62). Antibiotic use reduced the risk of MEM CD (aOR, 0.27; 95% CI, 0.11-0.67) and UC (aOR, 0.38; 95% CI, 0.18-0.80), but increased the risk in Caucasians (CD: aOR, 5.24; 95% CI, 2.13-12.90; and UC: aOR, 6.82; 95% CI, 2.67-17.38). Most hygiene markers (rural dwelling, pet ownership, pet feeding, and farm animal contact) reduced CD and UC risk in MEM (P < .05). In contrast, in Caucasians these hygiene markers lacked significance. Other significant risk factors include IBD family history, appendectomy, tonsillectomy, and breastfeeding. CONCLUSIONS: Differential IBD environmental risk factors exist between migrants and native Caucasians, indicating a dynamic interplay between environmental factors and IBD risk for immigrants that is distinct to those factors most relevant in native Caucasians.


Asunto(s)
Exposición a Riesgos Ambientales , Enfermedades Inflamatorias del Intestino/epidemiología , Adolescente , Adulto , Animales , Australia/epidemiología , Estudios de Casos y Controles , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Medio Oriente/epidemiología , Estudios Prospectivos , Grupos Raciales , Factores de Riesgo , Migrantes , Adulto Joven
9.
J Gastroenterol Hepatol ; 26(3): 484-91, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21155877

RESUMEN

BACKGROUND AND AIM: Recurrent stent obstruction necessitating reintervention is problematic and incompletely understood. The aim of the present study was to identify factor(s) predisposing to reintervention. METHODS: Retrospective review of patients (n = 117) referred to a single major endoscopic referral centre for palliative enteral stenting from 1999 to 2006. Twelve were excluded due to inadequate follow-up data (n = 7) or initial radiographic documentation (n = 5). A total of 105 patients (gastroduodenal n = 57, colonic n = 48) were therefore analyzed. The primary outcome of interest was recurrent obstruction necessitating reintervention. Kaplan-Meier analysis of potential factors predisposing to reintervention, including stent angulation (mild [<15°], moderate [15°-90°], severe [>90°]) was completed for 98 patients (technically successful enteral stenting). RESULTS: Technical and clinical success were achieved in 98 of 105 (93.3%) and 92 of 98 (93.9%) cases, respectively. Post-stenting median survival was 97.5 days (range 3-1054). Eighteen patients (18.4%) required reintervention for stent obstruction at a median time to reintervention of 85 days (range 7-481). Increased stent angulation (severe vs mild hazard ratio 6.73 (95% confidence interval 1.59-27.59), P = 0.009) was the only statistically significant factor in multivariate analysis predicting reintervention. CONCLUSIONS: Despite its limitation as a retrospective review, this study found that reintervention for stent obstruction is necessary in almost one in five cases, and increasing severity of stent angulation is the most important risk factor.


Asunto(s)
Neoplasias del Sistema Digestivo/complicaciones , Endoscopía Gastrointestinal/instrumentación , Obstrucción Intestinal/terapia , Falla de Prótesis , Stents , Anciano , Femenino , Humanos , Obstrucción Intestinal/diagnóstico por imagen , Obstrucción Intestinal/etiología , Estimación de Kaplan-Meier , Masculino , Nueva Gales del Sur , Cuidados Paliativos , Modelos de Riesgos Proporcionales , Radiografía , Retratamiento , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento
10.
Gastrointest Endosc ; 64(3): 351-7, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16923481

RESUMEN

BACKGROUND: Despite the recent improvement in techniques and patient selection, post-ERCP pancreatitis remains the most frequent and dreaded complication of ERCP. Recent studies suggest that pretreatment with glyceryl trinitrate (GTN) may prevent post-ERCP pancreatitis and improve cannulation success. OBJECTIVE: To evaluate the effect of transdermal GTN on ERCP cannulation success and post-ERCP pancreatitis. DESIGN: Prospective, double-blind, placebo-controlled trial. SETTING: Tertiary referral university hospital. PATIENTS: A total of 318 patients (mean age 62 years, 61% women) were randomized to either active (n = 155) or placebo (n = 163) arms. INTERVENTIONS: Active patch (GTN) versus placebo patch. MAIN OUTCOME MEASUREMENTS: Cannulation time and success. Post-ERCP pancreatitis rates. RESULTS: There was no significant difference between the active or placebo arms for the following: successful initial cannulation (96.8% vs 98.8%), deep cannulation (96.1% vs 98.8%), time to successful cannulation, use of guidewire (27% vs 25%) or needle knife (13% vs 13%), and post-ERCP pancreatitis (7.4% of placebo patients and 7.7% active patients). Multivariate analysis identified women, younger patients, pancreatogram, number of attempts on papilla, and poor pancreatic-duct emptying after opacification as risk factors for post-ERCP pancreatitis. Transdermal GTN did not reduce post-ERCP pancreatitis in any of the identified high-risk groups. CONCLUSIONS: Transdermal GTN did not improve the rate of success in ERCP cannulation or prevent post-ERCP pancreatitis in either average or high-risk patient groups.


Asunto(s)
Cateterismo/efectos adversos , Colangiopancreatografia Retrógrada Endoscópica/efectos adversos , Nitroglicerina/uso terapéutico , Pancreatitis/prevención & control , Vasodilatadores/uso terapéutico , Administración Cutánea , Anciano , Anciano de 80 o más Años , Colangiopancreatografia Retrógrada Endoscópica/métodos , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Nitroglicerina/administración & dosificación , Pancreatitis/epidemiología , Pancreatitis/etiología , Cuidados Preoperatorios , Estudios Prospectivos , Factores de Riesgo , Vasodilatadores/administración & dosificación
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