Double-contrast Research Articles

THE METHOD OF DOUBLE CONTRAST IN THE INTRAOPERATIVE DIAGNOSIS OF REGMATOGENIC RETINAL DETACHMENT

Usually, the recurrence rate of regmatogenic retinal detachment (ROS) after surgery ranges from 3% to 30%. In cases where the disease recurs after successful surgery, in 60% of cases the main factor is the progression of proliferative vitreoretinopathy (PVR), which makes it one of the most severe complications that can occur in the postoperative period. In addition, after removal or absorption of a tampon agent (in particular, endotamponade with silicone oil), recurrent retinal detachment may occur due to the inability to detect retinal rupture during surgery.Objective: this study is aimed at evaluating the effectiveness of diagnostic methods used during operations for regmatogenic retinal detachment. After completing the standard stages of central vitrectomy, the group of patients was divided into two equal groups: the first group included patients who received the double contrast method, and the second group (control) – patients who underwent the traditional surgical method.Results and discussion: in patients of the control group, there was a significant increase in the number of relapses of ROS. In addition, it was found that an increase in the number of retinal tears correlated with a greater likelihood of macular involvement; Statistical evaluation has shown that the absence of AST and tight adhesion of the posterior hyaloid membrane to the retina and small retinal tears increase the risk of recurrence of ROS due to the progression of PVR.

Conservative Management of Bowel Endometriosis: Cross-Sectional Analysis for Assessing Clinical Outcomes and Quality-of-Life.

Background/Objectives: Bowel endometriosis (BE) is characterized by the presence of endometrial-like tissue within the muscular layer of the bowel wall. When BE does not result in the severe obstruction to fecal transit and in the absence of (sub)occlusive symptoms, the decision to perform surgery can be challenging, as intestinal procedures are associated with higher complication rates and long-term bowel dysfunction. This cross-sectional study aims to evaluate the quality of life (QoL) in patients with BE who avoided surgery, as well as to investigate the impact of the characteristics of BE nodules on the QoL and intestinal function. Methods: A retrospective cross-sectional analysis was conducted involving 580 patients with BE who did not undergo surgery but were treated conservatively with medical therapy or expectant management between January 2017 and August 2022. The diagnosis of BE was established through transvaginal ultrasound and confirmed via double contrast barium enema. After at least one year of follow-up, the QoL and intestinal function were assessed using the Endometriosis Health Profile-5 (EHP-5) questionnaire and the Bowel Endometriosis Symptom (BENS) score, while pain symptoms were quantified with the Visual Analog Scale (VAS 0-10). Statistical analyses were performed to explore potential associations between the QoL and the characteristics of BE nodules (size, location, and evidence of stenosis), as well as the type and duration of medical therapy. Results: Patients with BE reported a satisfactory overall QoL, with a mean EHP-5 score of 105.42 ± 99.98 points and a VAS score below three across all pain domains. They did not demonstrate significant impairment in bowel function, as indicated by a mean BENS score of 4.89 ± 5.28 points. Notably, patients receiving medical therapy exhibited a better QoL compared to those not receiving treatment (p < 0.05), with the exception of postmenopausal patients, who reported the highest QoL overall (p < 0.05). Among the characteristics of BE, nodule location significantly impacted the QoL and symptom intensity, with low (rectal or rectosigmoid) nodules less tolerated compared to sigmoid nodules, particularly regarding non-menstrual pelvic pain (NMPP), dyschezia, and psychological impact on daily life (p < 0.05). Conclusions: Women can effectively manage BE conservatively in the absence of (sub)occlusive symptoms, even when large nodules are present, causing significant radiological stenosis. The characteristics of BE nodules do not significantly affect the QoL or symptom intensity; however, the location of BE nodules is a crucial factor negatively influencing these outcomes. Medical therapy may confer a beneficial impact on patients of reproductive age with BE, but its use should be carefully considered for those approaching menopause, weighing the risks and benefits.

Infrared Small Target Detection Based on Weighted Improved Double Local Contrast Measure

The robust detection of infrared small targets plays an important role in infrared early warning systems. However, the high-brightness interference present in the background makes it challenging. To solve this problem, we propose a weighted improved double local contrast measure (WIDLCM) algorithm in this paper. Firstly, we utilize a fixed-scale three-layer window to compute the double neighborhood gray difference to screen candidate target pixels and estimate the target size. Then, according to the size information of each candidate target pixel, an improved double local contrast measure (IDLCM) based on the gray difference is designed to enhance the target and suppress the background. Next, considering the structural characteristics of the target edge, we propose the variance-based weighting coefficient to eliminate clutter further. Finally, the targets are detected by an adaptive threshold. Extensive experimental results demonstrate that our method outperforms several state-of-the-art methods.

GI and GU fluoroscopy in common post-op oncologic surgeries: what you need to know about this leaky business!

Over the past several years, there has been a trend of decreasing screening or diagnostic fluoroscopic examinations ordered by clinical teams, particularly double contrast gastrointestinal studies. The underlying reason is due to increasing number of endoscopic procedures performed by Gastroenterology and Urology and usage of other imaging modalities, which are either more sensitive and/or offer the ability to obtain tissue for confirmation. Many fluoroscopic studies are now tailored toward patients who have undergone gastrointestinal or genitourinary oncologic surgeries, providing both functional and anatomic information, which are important tools for patient management. Some of these surgeries are very complex and an understanding of the postoperative anatomy and potential pitfalls is important to accurately evaluate for complications. The purpose of this article is to describe techniques and indications for common post-operative fluoroscopic procedures in gastrointestinal and genitourinary oncology while reviewing normal appearances. Complications, with emphasis on postoperative leaks, will be highlighted. Familiarity with the various types of gastrointestinal surgeries and urinary diversion techniques and knowledge of the expected postsurgical appearance is essential for achieving an accurate and prompt diagnosis of complications to allow for adequate treatment and management.

Multi-sensor data fusion-enabled lightweight convolutional double regularization contrast transformer for aerospace bearing small samples fault diagnosis

Aiming at the problems of low information utilization and lack of feature mining capability in multi-sensor fusion networks, this study presents a multi-sensor data fusion-enabled lightweight convolutional double regularization contrast transformer for aerospace bearing small samples fault diagnosis. Firstly, a metric termed integrated cliff entropy is devised to assign weights to vibration signals from diverse sensor channels. It aims to enhance the cyclic impulse characteristics within the fused signals, thereby facilitating more precise fault identification. Secondly, a lightweight Diwaveformer architecture is constructed as the backbone of contrast learning. It enables the global and local features of faulty signals to be comprehensively extracted with less computational effort. Finally, a double contrast loss is constructed to optimize the distribution of intra-class and inter-class features to improve the fault identification ability of the network with small samples. Additionally, a discard regularization method is designed to remove the projection head during the contrast learning process, further advancing the model lightweight. Our method achieved accuracies of 95.54% and 92.56% on two aerospace bearing datasets with extremely sparse training samples, which proved its superior performance.

Evaluating the effect of NPO status on mucosal coating during double contrast barium esophagrams.

Current guidelines for double contrast barium esophagography studies (BAS) suggest that patients should be nil per os (NPO) prior to completing BAS for optimal esophageal coating, although the time required varies between practices and institutions. It is believed that consumption of food or water disrupts the ability for thick barium contrast to properly coat the esophageal mucosa. Exams that are rescheduled for this reason can lead to delays in care, without substantial evidence that NPO status truly affects esophageal mucosal coating for these exams with current barium mixtures. The study aims to identify the necessity, or lack thereof, of standard NPO protocol in patients undergoing BAS, in effort to prevent unnecessary procedural delay. This study is an IRB-approved HIPAA-compliant study of 370 consecutive adult patients (115male/255 female, mean age 55) who underwent BAS at our institution from January to June of 2022. Patients were divided into two groups: <4 h NPO (n=334), and ≥4h NPO (n=36). Four abdominal radiologists blinded to NPO interval independently reviewed a random sample of approximately 92 patients (91-94) and graded esophageal coating on a 4-point-scale with 1 being insufficient coating and 4 being optimal coating. No significant statistical difference in mean esophageal coating score was found between the ≥4 h NPO cohort (3.04±SD 0.78) and the <4 h NPO cohort (2.97±SD 0.70; P=0.54). Subset analysis of patients who were NPO for <2 h (n=9) also showed no significant difference in mean esophageal coating score (3.11±SD 0.6; P=0.92), compared to the standard ≥4 NPO status. Non-adherence to standard NPO protocol prior to BAS studies did not result in a significant difference in esophageal coating when compared to traditional preprocedural fasting of 4 or more hours.

Rumor detection based on Attention Graph Adversarial Dual Contrast Learning.

It is becoming harder to tell rumors from non-rumors as social media becomes a key news source, which invites malicious manipulation that could do harm to the public's health or cause financial loss. When faced with situations when the session structure of comment sections is deliberately disrupted, traditional models do not handle them adequately. In order to do this, we provide a novel rumor detection architecture that combines dual comparison learning, adversarial training, and attention filters. We suggest the attention filter module to achieve the filtering of some dangerous comments as well as the filtering of some useless comments, allowing the nodes to enter the GAT graph neural network with greater structural information. The adversarial training module (ADV) simulates the occurrence of malicious comments through perturbation, giving the comments some defense against malicious comments. It also serves as a hard negative sample to aid double contrast learning (DCL), which aims to learn the differences between various comments, and incorporates the final loss in the form of a loss function to strengthen the model. According to experimental findings, our AGAD (Attention Graph Adversarial Dual Contrast Learning) model outperforms other cutting-edge algorithms on a number of rumor detection tasks. The code is available at https://github.com/icezhangGG/AGAD.git.

Расширение интраоперационных диагностических возможностей в хирургии регматогенной отслойки сетчатки методом двойного контрастирования

On average, the risk of recurrence increased in the postoperative period varies from 3 to 30 %. Among the relapses of ROS after successful surgical treatment, the progression of PVR is an established cause in 60 % of cases, being one of the most serious complications encountered in the postoperative period. It is also often the cause of a recurrence of retinal detachment after resorption of the tamponing agent, or after its removal (with endotamponade with silicone oil) is the banal failure to detect a retinal rupture during surgery. Objective. To compare intraoperative diagnostic techniques in surgery of regmatogenic retinal detachment. Material and methods. The study included 68 patients of different sexes with up to 1 month of age and different detachment configurations. After the standard stages of central vitrectomy, the patients were divided into 2 equal groups: the 1st (main) group consisted of patients who underwent the double-cauterization method, the 2nd (control) group consisted of patients operated in the standard way. Results and discussions. We have recorded a significantly frequent occurrence of relapses in patients in the control group. It was also found that an increase in the number of retinal tears increases the likelihood of ROS involving the macular zone, it was possible to statistically reliably confirm that the absence of ZOST and tight adhesion of the posterior hyaloid membrane to the retina, as well as the lower localization of retinal tears, increases the likelihood of recurrence of ROS due to the development of PVR. Keywords: retinal surface staining, double contrast, proliferative vitreoretinopathy, silicone oil, avitria, retinal detachment

Iron-based compounds coordinated with phospho-polymers as biocompatible probes for dual 31P/1H magnetic resonance imaging and spectroscopy

In this work, we present the synthesis and evaluation of magnetic resonance (MR) properties of novel phosphorus/iron-containing probes for dual 31P and 1H MR imaging and spectroscopy (MRI and MRS). The presented probes are composed of biocompatible semitelechelic and multivalent phospho-polymers based on poly(2-methacryloyloxyethyl phosphorylcholine) (pMPC) coordinated with small paramagnetic Fe3+ ions or superparamagnetic maghemite (γ-Fe2O3) nanoparticles via deferoxamine group linked to the end or along the polymer chains. All probes provided very short 1H T1 and T2 relaxation times even at low iron concentrations. The presence of iron had a significant impact on the shortening of 31P relaxation, with the effect being more pronounced for probes based on γ-Fe2O3 and multivalent polymer. While the water-soluble probe having one Fe3+ ion per polymer chain was satisfactorily visualized by both 31P-MRS and 31P-MRI, the probe with multiple Fe3+ ions could only be detected by 31P-MRS, and the probes consisting of γ-Fe2O3 nanoparticles could not be imaged by either technique due to their ultra-short 31P relaxations. In this proof-of-principle study performed on phantoms at a clinically relevant magnetic fields, we demonstrated how the different forms and concentrations of iron affect both the 1H MR signal of the surrounding water molecules and the 31P MR signal of the phospho-polymer probe. Thus, this double contrast can be exploited to simultaneously visualize body anatomy and monitor probe biodistribution.

Pneumothorax, Pneumomediastinum, and Cervical and Facial Massive Emphysema Secondary to Colonoscopy: A Rare Complication of Colonoscopy

Background. Colonoscopy is a resource used for the diagnosis, treatment, and monitoring of benign and malignant colorectal pathologies. The incidence of perforation is 0.03%–0.65% in diagnostic colonoscopy; however, the incidence can be up to 10 times higher in therapeutic interventions, such as polypectomies, increasing the risk of complications up to 0.07–2.1%. Materials and methods. Case report of a 71‐year‐old female who presents a rare complication due to a perforation in the sigmoid which developed pneumoperitoneum, pneumomediastinum, pneumothorax, and massive subcutaneous emphysema as a complication of a diagnostic colonoscopy where a biopsy of a friable lesion was performed. Results. A 71‐year‐old female that went to the emergency room due to acute generalized abdominal colic spasm pain with a duration of 7 hours, associated with significant abdominal distension, malaise, diaphoresis, progressive dyspnea, and massive subcutaneous emphysema that developed after performing panendoscopy and colonoscopy for diverticulosis follow‐up. An abdominal CT scan with double contrast was performed, reporting suggestive data of hollow viscus perforation, pneumoperitoneum, pneumomediastinum, pneumothorax, and massive subcutaneous emphysema in the thorax, neck, and skull base. She underwent an exploratory laparotomy finding a perforation in the sigmoid for which sigmoidectomy was performed, and for the pneumothorax and pneumomediastinum, endopleural tubes were placed in both hemithoraxes. The massive subcutaneous emphysema subsided with observation and oxygen. Conclusion. A rare complication of the use of colonoscopy as a diagnostic and therapeutic method is presented. The purpose of presenting this case is for the doctor who performs these interventions to suspect this complication in a timely manner, not delaying the diagnosis and carrying out an urgent therapeutic approach as in this case with exploratory laparotomy, finding the perforation site and carrying out the corresponding surgical management. We demonstrated that massive subcutaneous emphysema can be managed with observation if there is no other alarm data evident that required another surgical approach.

Comparison Between Dedicated Magnetic Resonance Angiography and T1 with Double Contrast for Avascular Stereoelectroencephalography Planning

Comparison Between Dedicated Magnetic Resonance Angiography and T1 with Double Contrast for Avascular Stereoelectroencephalography Planning

Underwater image enhancement via complementary advantage fusion of global and local contrast

Underwater images encounter a range of quality degradation challenges due to most wavelengths of light being attenuated by varying degrees of absorption in traveling underwater. To cope with these issues, we present a complementary advantage fusion method of global and local contrast, named CAFM. Successively, CAFM first compensate for the attenuation of each channel by exploiting the pixel intensity and distribution of each channel to get an image without color distortion. Subsequently, we employ the double histogram optimization contrast method to enhance the global contrast of the preprocessed image, while the mean and variance features of image blocks are utilized to enhance the local contrast of the preprocessed image. To get a high-quality underwater image, we employ a complementary advantage fusion method to combine the benefits of the two enhanced images via the complementary advantages between different feature maps. Extensive evaluation of three datasets demonstrates that our CAFM surpasses the compared methods. Additionally, the underwater images are enhanced by our CAFM with authentic colors, heightened contrast, and rich texture detailing.

Utility of Contrast-Enhanced Computed Tomography for Differentiating Pancreatic Ductal Adenocarcinoma from Inflammatory Mass in Chronic Calcific Pancreatitis

Abstract Objective The aim of this study was to identify the most useful contrast-enhanced computed tomography (CECT) features for differentiating pancreatic ductal adenocarcinoma (PDAC) from mass-forming chronic pancreatitis (MFCP) in chronic calcific pancreatitis (CCP). Methods In total, 101 patients with CCP and focal pancreatic mass formed the study group. Sixteen qualitative and four quantitative parameters were analyzed. Qualitative parameters included size, site, margin, intralesional hypodensity, collateral duct sign, abrupt pancreatic duct (PD) cutoff, upstream PD dilatation, distal pancreatic atrophy, double duct sign, enhancement pattern, contrast attenuation, peripancreatic inflammation, vascular involvement, regional nodes, and metastasis. Quantitative parameters included duct-to-body ratio, common bile duct (CBD) diameter, main pancreatic duct (MPD) diameter, and carcinoembryonic antigen 19-9 (CA19-9). Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy were calculated for prediction of PDAC. A receiver operating characteristic (ROC) curve analysis was performed and the area under ROC curve (AUROC) was calculated to determine diagnostic accuracy to assess the optimal cutoff. Results PDAC was confirmed in 48 patients and MFCP in 53 patients. A duct-to-body ratio greater than 0.48 had 95.5% sensitivity, 83.3% specificity, 80.8% PPV, 96.2% NPV, and 88.5% accuracy for predicting PDAC. A CBD diameter cutoff ≥9.5 mm had an accuracy of 75% (p &lt; 0.019) and an MPD cutoff ≥6.25 mm had an accuracy of 67.8% (p = 0.008) for predicting PDAC. On binary logistic regression, the duct-to-body ratio was found to be the significant independent factor associated with malignancy. Conclusion A duct-to-body ratio greater than 0.48, intralesional hypodensity, and abrupt duct cutoff are the most helpful computed tomography (CT) features for distinguishing PDAC from MFCP in CCP. On binary logistic regression, the duct-to-body ratio was found to be a significant independent factor. Interspersed normal parenchyma was observed as a very specific sign of MFCP. Intraparenchymal hypodensity has high specificity, but further validation is needed.

Differential Effects of Laxatives on Barium Sulfate Coating and Image Quality in Double-Contrast Barium Enema.

Diagnostic accuracy of double-contrast barium enema (DCBE) depends upon the barium sulfate coating efficiency in the colon. To evaluate effects of three laxatives on barium sulfate coating efficiency in the large intestine, sigmoid colon, and hepatic flexure in DCBE. This retrospective study included patients receiving DCBE after pre-procedure cleansing with Dulcolax® with castor oil (DC), Klean-Prep® (KP), or Fleet® . Patients' DCBE images were reviewed. Among 373 cases of DCBE, 151 received DC, 147 received KP, and 75 received Fleet. For DCBE, the optimal extent of barium sulfate residue coated on the wall of the large intestine is less than one-fourth of bowel wall width; the DC group had a higher percentage of less than one-fourth of bowel wall than that of the KP or Fleet group (both p < 0.0167). DC, KP and Fleet have comparable barium sulfate coating efficiency in the sigmoid colon. However, in the hepatic flexure, the DC group had a higher percentage of barium sulfate coating without interruption than that of the KP or Fleet groups (both p < 0.0167). DC has a better barium sulfate coating efficiency in the hepatic flexure compared with KP and Fleet.

Changes in proprioception at different time points following anterior cruciate ligament injury or reconstruction

PurposeTo investigate the changes in 30° and 60° position sense in patients with anterior cruciate ligament (ACL) injury at different time points after injury and reconstruction.MethodsPatients were divided into six groups according to time after ACL injury and reconstruction: group A (ACL injury 1.5–6 months), group B (ACL injury 6–12 months), group C (ACL injury > 12 months), group D (postoperative ACL reconstruction 1–6 months), group E (postoperative ACL reconstruction > 6 months), and group F consisting of 14 healthy adults (control group). The ability of the affected leg to reproduce the same joint position during knee flexion was tested using active joint position sense assays to assess proprioception in both the lower extremities of the patient or between groups.ResultsProprioception decreased rapidly during the early stages of ACL injury. Significant difference in the affected side at 30° compared to the healthy side (Group A: 4.70 (4.78, 9.00) vs 4.15 (3.35, 6.13), P = 0.03; Group B: 2.90 (0.48, 4.56) vs 8.30 (4.18, 10.43), P = 0.001; Group E: 6.25 (2.55, 11.60) vs 9.60 (3.90, 12.73), P = 0.009). However, no significant differences were detected for a double lower limb contrast of 60° (Group A: 5.1 (1.00, 8.00) vs 3.00 (0.75, 3.55), P = 0.044). Finally, the affected side of patients in groups C, D and E had significant differences in position perception at 30° compared with healthy subjects (P < 0.01), and the affected side of patients in groups C and E had significant differences in position sense at 60° compared with healthy subjects (P < 0.01).ConclusionACL injury had a greater impact on the patient's 30° position sense, with only a small impact for 60°. Further, the early and middle proprioception recovery stages after ACL injury were the best before surgery. Finally, proprioception recovery training should be performed soon after injury.

Can expiratory or inspiratory contrast-enhanced computed tomography be more efficient for fast-track cannulation of the right adrenal vein in adrenal venous sampling?

This study compares the usefulness of expiratory arterial phase (EAP)-contrast-enhanced computed tomography (CT) (CECT) with that of inspiratory arterial phase (IAP)-CECT in adrenal venous sampling (AVS). Sixty-four patients who underwent AVS and CECT at the authors' hospital between April 2013 and June 2019 were included in this study. The patients were classified into the following two groups: EAP (32 patients) and IAP (32 patients) groups. The single arterial phase images were obtained at 40 seconds in the IAP group. The double arterial phase images were obtained at 40 seconds in the early arterial phase and 55 seconds in the late arterial phase in the EAP group. The authors then compared the right adrenal vein (RAV) visualization rate on the CECT, the difference between the CECT images and adrenal venograms in the localization of the RAV orifice, the cannulation time to the RAV, and the volume of contrast agent administered intraoperatively between the two groups. The rates of the RAV visualization in the EAP group were 84.4% in the early arterial phase, 93.8% in the late arterial phase, and 100% in the combined early and late arterial phases. The rate of the RAV visualization in the IAP group was 96.9%. There was no significant difference between the two groups in terms of the rate of the RAV visualization. However, there was a small difference in the location of the RAV orifice between the CECT images and adrenal venograms in the EAP group as compared with the IAP group (P < 0.001). The median time to the RAV catheterization was significantly shorter in the EAP group (27.5 minutes) than in the IAP group (35.5 minutes; P = 0.035). The rates of the RAV visualization in the EAP group were not significant between the early arterial phase, late arterial phase, and combined early and late arterial phases (P = 0.066). However, the mean volume CT dose index in the combined early and late arterial phases was significantly higher than in the early and late arterial phases (P < 0.001). The EAP-CECT is more useful for increasing the speed of the RAV cannulation due to the small difference in the localization of the RAV orifice compared to IAP-CECT. However, since EAP-CECT has double contrast arterial phases and increased radiation exposure compared to IAP-CECT, only the late arterial phase may be acceptable to reduce radiation exposure.

Endoscopist volume and the quality of colonoscopy of the Korean National Cancer Screening Program.

6627 Background: The Korean government established the National Cancer Screening Program (KNCSP). The KNCSP has provided annual faecal immunochemical test (FIT) for adults aged 50 years or older, and colonoscopy or a double-contrast barium enema test to those with positive results from the FIT. High-quality screening colonoscopy is mandatory to achieve maximum possible CRC prevention. The case volume has been shown to correlate with outcomes in surgical specialties. In contrast, relevant data on colonoscopy is limited. This study aimed to assess the quality indicators of organized CRC screening according to annual colonoscopy volume using KNCSP data. Methods: We used the KNCSP data from 2018 to 2020, which accounted for 378,354 colonoscopy examinations. We used cancer registration data of an extended health insurance program using ICD-11 codes (C18-20). A total of 12,109 CRC patients were registered within 1 year of the date of colonoscopy. We calculated the annual number of colonoscopy examinations by an individual endoscopist. We excluded endoscopists who had a very low or high number of examinations with the highest 1% or lowest 1% as outliers. The final number of endoscopists was 16,552 and colonoscopy examinations were 331,231 during 2018–2020. The annual colonoscopy volume by individual endoscopists was divided into four groups (2–12, 13–24, 25–36, and 37 or more examinations). Multiple linear regression analysis was performed to confirm the association between test accuracy indicators and colonoscopy frequency using a generalized linear model (GLM). We calculated the estimates of the rates for each indicator by adjusting the year. Results: The positive and false positive rates, sensitivity, specificity, and positive predictive value were 4.09%, 1.07%, 83.53%, 98.93%, and 74.68%, respectively. The cancer detection and interval cancer rates were 30.53‰ and 6.29‰, respectively. Quality indicators were related to the annual colonoscopy volume of the endoscopist. Endoscopists with a higher annual colonoscopy volume were more likely to have higher sensitivity, specificity, and positive predictive value than those with a lower annual colonoscopy volume. Endoscopists with higher annual colonoscopy volumes were more likely to have lower positive rates, cancer detection rates, false positive rates, and interval cancers rate than those with lower annual colonoscopy volumes. Conclusions: This study found that the annual volume of colonoscopy examinations was associated with better colonoscopy quality in an organized CRC screening program. A high colonoscopy load could be a sign of substantial experience and lead to better outcomes, as has been shown for surgery. The relationship between quality indicators and case volume is logical and plausible; therefore, more research is required to determine the number of cases that need to be performed in a year to adequately maintain high colonoscopy quality.

Double-contrast barium enema is no longer justified as a backup examination for colonoscopy in the population screening program: Population study in an organized fecal immunochemical test-based screening program.

Currently, some countries still acknowledge double-contrast barium enema (DCBE) as a backup confirmatory examination when colonoscopy is not feasible or incomplete in colorectal cancer (CRC) screening programs. This study aims to compare the performance of colonoscopy and DCBE in terms of the risk of incident CRC after negative results in the fecal immunochemical test (FIT)-based Taiwan Colorectal Cancer Screening Program. Subjects who had positive FITs and received confirmatory exams, either colonoscopy or DCBE, without the findings of neoplastic lesions from 2004 to 2013 in the screening program comprised the study cohort. Both the colonoscopy and DCBE subcohorts were followed until the end of 2018 and linked to the Taiwan Cancer Registry to identify incident CRC cases. Multivariate analysis was conducted to compare the risk of incident CRC in both subcohorts after controlling for potential confounders. A total of 102 761 colonoscopies and 5885 DCBEs were performed after positive FITs without neoplastic findings during the study period. By the end of 2018, 2113 CRCs (2.7 per 1000 person-years) and 368 CRCs (7.6 per 1000 person-years) occurred in the colonoscopy and DCBE subcohorts, respectively. After adjusting for major confounders, DCBE had a significantly higher risk of incident CRC than colonoscopy, with an adjusted HR of 2.81 (95% CI=2.51-3.14). In the FIT screening program, using DCBE as a backup examination was associated with a nearly threefold risk of incident CRC compared with colonoscopy, demonstrating that it is no longer justified as a backup examination for incomplete colonoscopy.

Contrast Enhancement in MRI Using Combined Double Action Contrast Agents and Image Post-Processing in the Breast Cancer Model.

Gd- and Fe-based contrast agents reduce T1 and T2 relaxation times, respectively, are frequently used in MRI, providing improved cancer detection. Recently, contrast agents changing both T1/T2 times, based on core/shell nanoparticles, have been introduced. Although advantages of the T1/T2 agents were shown, MR image contrast of cancerous versus normal adjacent tissue induced by these agents has not yet been analyzed in detail as authors considered changes in cancer MR signal or signal-to-noise ratio after contrast injection rather than changes in signal differences between cancer and normal adjacent tissue. Furthermore, the potential advantages of T1/T2 contrast agents using image manipulation such as subtraction or addition have not been yet discussed in detail. Therefore, we performed theoretical calculations of MR signal in a tumor model using T1-weighted, T2-weighted, and combined images for T1-, T2-, and T1/T2-targeted contrast agents. The results from the tumor model are followed by in vivo experiments using core/shell NaDyF4/NaGdF4 nanoparticles as T1/T2 non-targeted contrast agent in the animal model of triple negative breast cancer. The results show that subtraction of T2-weighted from T1-weighted MR images provides additional increase in the tumor contrast: over two-fold in the tumor model and 12% in the in vivo experiment.

Colon Cancer Screening Methods: 2023 Update.

Colorectal cancer (CRC) is a significant cause of morbidity and mortality worldwide. National screening guidelines have been implemented to identify and remove precancerous polyps before they become cancer. Routine CRC screening is advised for people with average risk starting at age 45 because it is a common and preventable malignancy.Various screening modalities are currently in use, ranging from stool-based tests (fecal occult blood test (FOBT), fecal immunochemical test (FIT), and FIT-DNA test), radiologic tests (computed tomographic colonography (CTC), double contrast barium enema), and visual endoscopic examinations (flexible sigmoidoscopy (FS), colonoscopy, and colon capsule endoscopy (CCE)) with their varying sensitivity and specificity. Biomarkers also play a vital role in assessing the recurrence of CRC. This review offers a summary of the current screening options, including biomarkers available to detect CRC, highlighting the benefits and challenges encompassing each screening modality.