55 research outputs found
Multi-Scale Feature Fusion using Parallel-Attention Block for COVID-19 Chest X-ray Diagnosis
Under the global COVID-19 crisis, accurate diagnosis of COVID-19 from Chest
X-ray (CXR) images is critical. To reduce intra- and inter-observer
variability, during the radiological assessment, computer-aided diagnostic
tools have been utilized to supplement medical decision-making and subsequent
disease management. Computational methods with high accuracy and robustness are
required for rapid triaging of patients and aiding radiologists in the
interpretation of the collected data. In this study, we propose a novel
multi-feature fusion network using parallel attention blocks to fuse the
original CXR images and local-phase feature-enhanced CXR images at
multi-scales. We examine our model on various COVID-19 datasets acquired from
different organizations to assess the generalization ability. Our experiments
demonstrate that our method achieves state-of-art performance and has improved
generalization capability, which is crucial for widespread deployment.Comment: Accepted for publication at the Journal of Machine Learning for
Biomedical Imaging (MELBA) https://melba-journal.org/2023:00
Multi-Feature Vision Transformer via Self-Supervised Representation Learning for Improvement of COVID-19 Diagnosis
The role of chest X-ray (CXR) imaging, due to being more cost-effective,
widely available, and having a faster acquisition time compared to CT, has
evolved during the COVID-19 pandemic. To improve the diagnostic performance of
CXR imaging a growing number of studies have investigated whether supervised
deep learning methods can provide additional support. However, supervised
methods rely on a large number of labeled radiology images, which is a
time-consuming and complex procedure requiring expert clinician input. Due to
the relative scarcity of COVID-19 patient data and the costly labeling process,
self-supervised learning methods have gained momentum and has been proposed
achieving comparable results to fully supervised learning approaches. In this
work, we study the effectiveness of self-supervised learning in the context of
diagnosing COVID-19 disease from CXR images. We propose a multi-feature Vision
Transformer (ViT) guided architecture where we deploy a cross-attention
mechanism to learn information from both original CXR images and corresponding
enhanced local phase CXR images. We demonstrate the performance of the baseline
self-supervised learning models can be further improved by leveraging the local
phase-based enhanced CXR images. By using 10\% labeled CXR scans, the proposed
model achieves 91.10\% and 96.21\% overall accuracy tested on total 35,483 CXR
images of healthy (8,851), regular pneumonia (6,045), and COVID-19 (18,159)
scans and shows significant improvement over state-of-the-art techniques. Code
is available https://github.com/endiqq/Multi-Feature-ViTComment: Accepted to the 2022 MICCAI Workshop on Medical Image Learning with
Limited and Noisy Dat
Posterior cricoid region fluoroscopic findings: the posterior cricoid plication.
The region posterior to the cricoid cartilage is challenging to assess fluoroscopically. The purpose of this investigation is to critically evaluate the posterior cricoid (PC) region on fluoroscopy and describe patterns of common findings. This was a case control study. All fluoroscopic swallowing studies performed between June 16, 2009, and February 9, 2010, were reviewed for features seen in the PC region. These findings were categorized into distinct patterns and compared to fluoroscopic studies performed in a cohort of normal volunteers. Two hundred patient studies and 149 healthy volunteer studies were reviewed. The mean age of the referred patient cohort and the volunteer cohort was 57 years (±19) and 61 years (±16), respectively (p > 0.05). The patient cohort was 53% male and the control cohort was 56% female (p > 0.05). Four groups were identified. Pharyngoesophageal webs were seen in 7% (10/149) of controls and 14% (28/200) of patients (p = 0.03). A PC arch impression was seen in 16% of patients (32/200) and controls (24/149) (p = 1). A PC plication was demonstrated in 23% (34/149) of controls and 30% (60/200) of patients (p = 0.13). No distinctive PC region findings were seen in 54% (81/149) of controls and 42% (84/200) of referred patients (p = 0.02). Four patients (2%) had both a web and a PC plication. Four categories of PC region findings were identified (unremarkable PC region, web, PC arch impression, and PC plication). Both patients referred for swallowing studies and healthy volunteers demonstrated esophageal webs, PC arch impressions, and PC plications. Only webs were more common in patients than in control subjects (p = 0.03). The PC impression and PC plication are likely to represent normal variants that may be identified on fluoroscopic swallow studies
Assessment of the Albumin-Bilirubin (ALBI) Grade as a Prognostic Indicator for Hepatocellular Carcinoma Patients Treated With Radioembolization.
OBJECTIVE: As the utility of Child-Pugh (C-P) class is limited by the subjectivity of ascites and encephalopathy, we evaluated a previously established objective method, the albumin-bilirubin (ALBI) grade, as a prognosticator for yttrium-90 radioembolization (RE) treatment for patients with hepatocellular carcinoma (HCC).
MATERIALS AND METHODS: A total of 117 patients who received RE for HCC from 2 academic centers were reviewed and stratified by ALBI grade, C-P class, and Barcelona Clinic Liver Cancer stage. The overall survival (OS) according to these 3 criteria was evaluated by Kaplan-Meier survival analysis. The utilities of C-P class and ALBI grade as prognostic indicators were compared using the log-rank test. Multivariate Cox regression analysis was performed to identify additional predictive factors.
RESULTS: Patients with ALBI grade 1 (n=49) had superior OS than those with ALBI grade 2 (n=65) (P=0.01). Meanwhile, no significant difference was observed in OS between C-P class A (n=100) and C-P class B (n=14) (P=0.11). For C-P class A patients, the ALBI grade (1 vs. 2) was able to stratify 2 clear and nonoverlapping subgroups with differing OS curves (P=0.03). Multivariate Cox regression test identified alanine transaminase, Barcelona Clinic Liver Cancer stage, and ALBI grade as the strongest prognostic factors for OS (P\u3c0.10).
CONCLUSIONS: ALBI grade as a prognosticator has demonstrated clear survival discrimination that is superior to C-P class among HCC patients treated with RE, particularly within the subgroup of C-P class A patients. ALBI grade is useful for clinicians to make decisions as to whether RE should be recommended to patients with HCC
Balloon-assisted occlusion of the internal iliac arteries in patients with placenta accreta/percreta.
BACKGROUND: Placenta accreta/percreta is a leading cause of third trimester hemorrhage and postpartum maternal death. The current treatment for third trimester hemorrhage due to placenta accreta/percreta is cesarean hysterectomy, which may be complicated by large volume blood loss.
PURPOSE: To determine what role, if any, prophylactic temporary balloon occlusion and transcatheter embolization of the anterior division of the internal iliac arteries plays in the management of patients with placenta accreta/percreta.
METHODS: The records of 28 consecutive patients with a diagnosis of placenta accreta/percreta were retrospectively reviewed. Patients were divided into two groups. Six patients underwent prophylactic temporary balloon occlusion, followed by cesarean section, transcatheter embolization of the anterior division of the internal iliac arteries and cesarean hysterectomy (n = 5) or uterine curettage (n = 1). Twenty-two patients underwent cesarean hysterectomy without endovascular intervention. The following parameters were compared in the two groups: patient age, gravidity, parity, gestational age at delivery, days in the intensive care unit after delivery, total hospital days, volume of transfused blood products, volume of fluid replacement intraoperatively, operating room time, estimated blood loss, and postoperative morbidity and mortality.
RESULTS: Patients in the embolization group had more frequent episodes of third trimester bleeding requiring admission and bedrest prior to delivery (16.7 days vs. 2.9 days), resulting in significantly more hospitalization time in the embolization group (23 days vs. 8.8 days) and delivery at an earlier gestational age than in those in the surgical group (32.5 weeks). There was no statistical difference in mean estimated blood loss, volume of replaced blood products, fluid replacement needs, operating room time or postoperative recovery time.
CONCLUSION: Our findings do not support the contention that in patients with placenta accreta/percreta, prophylactic temporary balloon occlusion and embolization prior to hysterectomy diminishes intraoperative blood loss
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