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1.
Surg Endosc ; 33(5): 1687-1692, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30693391

RESUMEN

BACKGROUND: Undetected bowel perforations occur in 0.3-1% of laparoscopic surgical procedures with an associated mortality rate of 5.3%. OBJECTIVE: The purpose of the study was to evaluate the clinical feasibility of a novel medical device to accurately detect bowel gas, specifically hydrogen (H2) and methane (CH4), from a sample of gas from the abdominal cavity during laparoscopic surgery when a known bowel wall perforation has occurred. SETTING: University (Academic) Hospital. METHODS: A prospective single arm study was composed of 8 patients undergoing a standard laparoscopic roux-en-y gastric bypass. At seven time points during the operation intra-abdominal gas was pulled from the abdominal cavity and analyzed using the novel device for H2 and CH4. The time points included after insufflation (T1), after first jejunotomy (T2), after closure of jejunotomy (T3), after recycle of carbon dioxide gas (T4), after gastrostomy (T5), after jejunotomy (T6), at procedure end (T7). RESULTS: Eight patients were enrolled in the study; in 7 (87.5%) patients data from all 7 time points were obtained. After the first opening of the small bowel (T2) mean hydrogen levels were significantly increased compared to baseline hydrogen levels (T1, T4, T7) (p < 0.001). At all time points, there was no significant detection of methane. There were no intra-operative or post-operative complications during the study. CONCLUSION: Hydrogen gas is released into the intra-abdominal cavity when bowel is opened and can be detected in real time using a novel device during laparoscopic surgery. The presence or absence of hydrogen directly correlates to whether the bowel is open (perforated) or intact. This device could be used in the future to detect unintended bowel perforations during laparoscopic surgery, prior to the conclusion of the operation. This technology could also potentially lead to novel mechanism for detecting postoperative leaks using gas detection technology.


Asunto(s)
Derivación Gástrica/métodos , Perforación Intestinal/diagnóstico , Laparoscopía/métodos , Obesidad Mórbida/cirugía , Cavidad Abdominal , Adulto , Femenino , Humanos , Hidrógeno/análisis , Intestino Delgado/cirugía , Masculino , Metano/análisis , Persona de Mediana Edad , Estudios Prospectivos
2.
J Med Radiat Sci ; 71(1): 156-162, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37584089

RESUMEN

The indications for liver stereotactic body radiation therapy (SBRT) continue to expand in the management of liver cancer due to the improved rates of local control with acceptable normal tissue toxicity. Changes in internal anatomy, such as the bowel, may negatively impact the precision of treatment delivery of SBRT liver treatment by influencing daily image matching. Institutions have developed various approaches to promoting bowel volume consistency. One such strategy is the administration of pharmaceuticals. The administration of pharmaceuticals, such as Simethicone, has been adopted by the Princess Alexandra Hospital Radiation Oncology Department (ROPAIR) as a method to promote consistency in the amount of bowel gas observed in liver cancer patients. This case series examines a group of patients treated at ROPAIR with liver SBRT to determine whether current practices effectively reduce the impact of bowel volume variations for liver cancer patients. Initial observations from this hypothesis generating research suggest potential improved consistency of the small bowel's anatomical position for liver SBRT patients who were administered Simethicone (Bowel bag dice similarity coefficient - Simethicone group = 0.79-0.92, Standard group = 0.24-0.93). However, it appeared that this strategy alone may not be entirely effective achieving consistency in the amount of bowel gas present throughout the duration of treatment. Further investigation into the refinement of liver SBRT pre-treatment preparation is therefore recommended.


Asunto(s)
Neoplasias Hepáticas , Radiocirugia , Humanos , Preparaciones Farmacéuticas , Simeticona , Radiocirugia/efectos adversos , Neoplasias Hepáticas/radioterapia , Neoplasias Hepáticas/etiología , Neoplasias Hepáticas/cirugía
3.
Cancers (Basel) ; 16(3)2024 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-38339393

RESUMEN

(1) Background: Proton therapy, a precise form of radiation treatment, can be significantly affected by variations in bowel content. The purpose was to identify the most beneficial gantry angles that minimize deviations from the treatment plan quality, thus enhancing the safety and efficacy of proton therapy for Wilms' tumor patients. (2) Methods: Thirteen patients with Wilms' tumor, enrolled in the SJWT21 clinical trial, underwent proton therapy. The variations in bowel gas were systematically monitored using daily Cone Beam Computed Tomography (CBCT) imaging. Air cavities identified in daily CBCT images were analyzed to construct daily verification plans and measure water equivalent path length (WEPL) changes. A worst-case scenario simulation was conducted to identify the safest beam angles. (3) Results: The study revealed a maximum decrease in target dose (ΔD100%) of 8.0%, which corresponded to a WEPL variation (ΔWEPL) of 11.3 mm. The average reduction in target dose, denoted as mean ΔD100%, was found to be 2.8%, with a standard deviation (SD) of 3.2%. The mean ΔWEPL was observed as 3.3 mm, with an SD of 2.7 mm. The worst-case scenario analysis suggested that gantry beam angles oriented toward the patient's right and posterior aspects from 110° to 310° were associated with minimized WEPL discrepancies. (4) Conclusions: This study comprehensively evaluated the influence of bowel gas variability on treatment plan accuracy and proton range uncertainties in pediatric proton therapy for Wilms' tumor.

4.
Phys Eng Sci Med ; 46(2): 659-668, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36944832

RESUMEN

Since particle beam distribution is vulnerable to change in bowel gas because of its low density, we developed a deep neural network (DNN) for bowel gas segmentation on X-ray images. We used 6688 image datasets from 209 cases as training data, 736 image datasets from 23 cases as validation data and 102 image datasets from 51 cases as test data (total 283 cases). For the training data, we prepared three types of digitally reconstructed radiographic (DRR) images (all-density, bone and gas) by projecting the treatment planning CT image data. However, the real X-ray images acquired in the treatment room showed low contrast that interfered with manual delineation of bowel gas. Therefore, we used synthetic X-ray images converted from DRR images in addition to real X-ray images.We evaluated DNN segmentation accuracy for the synthetic X-ray images using Intersection over Union, recall, precision, and the Dice coefficient, which measured 0.708 ± 0.208, 0.832 ± 0.170, 0.799 ± 0.191, and 0.807 ± 0.178, respectively. The evaluation metrics for the real X-images were less accurate than those for the synthetic X-ray images (0.408 ± 0237, 0.685 ± 0.326, 0.490 ± 0272, and 0.534 ± 0.271, respectively). Computation time was 29.7 ± 1.3 ms/image. Our DNN appears useful in increasing treatment accuracy in particle beam therapy.


Asunto(s)
Procesamiento de Imagen Asistido por Computador , Tomografía Computarizada por Rayos X , Tomografía Computarizada por Rayos X/métodos , Rayos X , Procesamiento de Imagen Asistido por Computador/métodos , Redes Neurales de la Computación
5.
Clin Oncol (R Coll Radiol) ; 33(3): e132-e142, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-32962907

RESUMEN

AIMS: Pencil beam scanning (PBS) proton therapy is an increasingly used radiation modality for childhood malignancies due to its ability to minimise dose to surrounding organs. However, the dosimetry is extremely sensitive to anatomical and density changes. The aims of this study were to investigate if there is a dosimetric benefit or detriment with PBS for paediatric abdominal neuroblastoma, assess gastrointestinal air variability and its dosimetric consequences, plus identify if there are factors that could assist case selection for PBS referral. MATERIALS AND METHODS: Twenty neuroblastoma cases were double-planned with PBS and intensity-modulated arc therapy (IMAT). Cases were divided into unilateral, midline unilateral and midline bilateral locations in relation to the kidneys. Plans were recalculated after the gastrointestinal volume was simulated as air (Hounsfield Units -700) and water (Hounsfield Units 0), then compared with nominal plans (recalculated - nominal, ΔD). Forty-three weekly cone beam computed tomography scans were analysed to quantify gastrointestinal air variability during treatment. RESULTS: PBS reduced the mean dose to normal tissues at all tumour locations, particularly unilateral tumours. However, 15% had better dosimetry with IMAT, all of which were midline tumours. Increased gastrointestinal air caused significant compromises to PBS versus IMAT plans for midline tumours [median/maximum ΔD95% clinical target volume (CTV) -2.4%/-15.7% PBS versus 1.4%/0% IMAT, P = 0.003], whereas minimal impact was observed for unilateral tumours (ΔD95% CTV -0.5%/-1.9% PBS versus 0.5%/-0.5% IMAT, P = 0.008). D95% CTV was significantly decreased in PBS plans if planning target volume (PTV) ≥400 cm3 (median -4.1%, P = 0.001) or PTV extension ≥60% anterior to vertebral body (-2.1%, P = 0.002). A larger variation in gastrointestinal air was observed in patients treated under general anaesthesia (median 38.4%) versus awake (11.5%); P = 0.004. CONCLUSION: In this planning study, tumours at the unilateral location consistently showed improved dose reductions to normal tissue with minimal dose degradation from increased gastrointestinal air with PBS plans. Tumour location, PTV volume and anterior extension of PTV are useful characteristics in facilitating patient selection for PBS.


Asunto(s)
Neuroblastoma , Terapia de Protones , Radioterapia de Intensidad Modulada , Niño , Colon , Humanos , Neuroblastoma/diagnóstico por imagen , Neuroblastoma/radioterapia , Órganos en Riesgo , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador
6.
Radiol Case Rep ; 16(2): 246-249, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33304435

RESUMEN

Hepatic portal venous gas (HPVG) is a rare imaging finding in infants and usually indicative of a severe disease process such as necrotizing enterocolitis, bowel ischemia, or bowel wall rupture / infarction. The diagnosis of HPVG may have serious implications such as parenteral nutrition, antibiotics and even surgery. In this case, we present an 8-week-old male with a history of prematurity presenting with HPVG, later concluded to be caused by milk protein allergy. Milk protein allergy is a rare cause of HPVG, but it should be recognized due to its benignity and potential prevention of unnecessary testing and interventions.

7.
Asian J Surg ; 42(1): 126-130, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29366637

RESUMEN

BACKGROUND: The aim of this study was to investigate the impact of Daikenchuto (DKT) on early postoperative outcomes after living donor liver transplantation (LDLT), focusing on the prevention of abdominal distension and bacterial translocation. METHODS: Adult LDLT recipients were prospectively divided into 2 groups, who were administered DKT (n = 20, group A) or not (n = 20, group B). The area of bowel gas defined as gas volume score (GVS) 7 days after LDLT was calculated. Postoperative liver function tests, the development of bacterial, viral, and fungal infections, and GVS after LDLT were reviewed. RESULTS: There were no significant differences in liver function tests and ammonia level after LDLT. Also, the rates of infection and the result of culture study were not different between groups. The median GVS 7 days after LDLT was not significantly different between groups A (0.26 (range, 0.12-0.58)) and B (0.23 (range, 0.15-0.42)). CONCLUSIONS: No positive impact was observed for 14-day DKT administration after LDLT, in terms of preventing infection or abdominal distension.


Asunto(s)
Dolor Abdominal/prevención & control , Infecciones Bacterianas/prevención & control , Trasplante de Hígado , Donadores Vivos , Extractos Vegetales/administración & dosificación , Cuidados Posoperatorios , Complicaciones Posoperatorias/prevención & control , Adulto , Anciano , Traslocación Bacteriana , Femenino , Gases , Humanos , Pruebas de Función Hepática , Masculino , Persona de Mediana Edad , Panax , Periodo Posoperatorio , Estudios Prospectivos , Resultado del Tratamiento , Zanthoxylum , Zingiberaceae
8.
Rev. imagem ; 29(4): 133-138, out.-dez. 2007. ilus
Artículo en Portugués | LILACS | ID: lil-542268

RESUMEN

Os objetivos deste trabalho foram demonstrar os padrões aéreos normais e patológicos do tubo digestivo em radiografias simples de abdome do recém-nascido, com ênfase no diagnóstico diferencial, sendo apresentados, em alguns casos, exames radiológicos contrastados.


In order to evaluate normal and pathologic bowel gas patterns in the newborn, we have retrospectively analyzed abdominal plain films, and emphasized the differential diagnosis. In some cases, we selected contrast gastrointestinal studies to illustrate the differential diagnosis.


Asunto(s)
Humanos , Recién Nacido , Ano Imperforado , Atresia Biliar , Hernia Diafragmática/congénito , Hernia Diafragmática , Tracto Gastrointestinal/anatomía & histología , Tracto Gastrointestinal/patología , Tracto Gastrointestinal , Diagnóstico Diferencial
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