Improving lung nodule segmentation in thoracic CT scans through the ensemble of 3D U-Net models.

PURPOSE: The current study explores the application of 3D U-Net architectures combined with Inception and ResNet modules for precise lung nodule detection through deep learning-based segmentation technique. This investigation is motivated by the objective of developing a Computer-Aided Diagnosis (CAD) system for effective diagnosis and prognostication of lung nodules in clinical settings. METHODS: The proposed method trained four different 3D U-Net models on the retrospective dataset obtained from AIIMS Delhi. To augment the training dataset, affine transformations and intensity transforms were utilized. Preprocessing steps included CT scan voxel resampling, intensity normalization, and lung parenchyma segmentation. Model optimization utilized a hybrid loss function that combined Dice Loss and Focal Loss. The model performance of all four 3D U-Nets was evaluated patient-wise using dice coefficient and Jaccard coefficient, then averaged to obtain the average volumetric dice coefficient (DSCavg) and average Jaccard coefficient (IoUavg) on a test dataset comprising 53 CT scans. Additionally, an ensemble approach (Model-V) was utilized featuring 3D U-Net (Model-I), ResNet (Model-II), and Inception (Model-III) 3D U-Net architectures, combined with two distinct patch sizes for further investigation. RESULTS: The ensemble of models obtained the highest DSCavg of 0.84 ± 0.05 and IoUavg of 0.74 ± 0.06 on the test dataset, compared against individual models. It mitigated false positives, overestimations, and underestimations observed in individual U-Net models. Moreover, the ensemble of models reduced average false positives per scan in the test dataset (1.57 nodules/scan) compared to individual models (2.69-3.39 nodules/scan). CONCLUSIONS: The suggested ensemble approach presents a strong and effective strategy for automatically detecting and delineating lung nodules, potentially aiding CAD systems in clinical settings. This approach could assist radiologists in laborious and meticulous lung nodule detection tasks in CT scans, improving lung cancer diagnosis and treatment planning.

Fatal adult-onset diaphragmatic hernia in the context of the COVID-19 pandemic.

Late-presenting or "Adult-Onset" Diaphragmatic Hernia is uncommon, especially in individuals with no history of trauma. The non-traumatic diaphragmatic hernia may be a Congenital Diaphragmatic Hernia [CDH] lately manifested as a sequela to an iatrogenic intervention or prolonged infections. We aim to explore the genetic correlations in "adult-onset" CDH, with an insight into the indirect contribution of the COVID-19 pandemic towards the fatal outcome.In this report, we present a case of an adult female who died from the complications of an undiagnosed adult-onset diaphragmatic hernia, deemed completely preventable, if not for the global COVID-19 pandemic. There was no prior history of physical trauma or medical history of any relevance.Early diagnosis and rapid surgical intervention remain the keystone management for successfully treating individuals affected by this entity. The decedent in question presented with symptoms demanding hospital stay for investigations that would have aided in timely diagnosis and prevented death. However, the excessive fear of COVID-19 prevented the patient from undergoing hospitalization and follow-up, delaying the diagnosis and leading to death.

Fatal adult-onset diaphragmatic hernia in the context of the COVID-19 pandemic

ABSTRACT Late-presenting or "Adult-Onset" Diaphragmatic Hernia is uncommon, especially in individuals with no history of trauma. The non-traumatic diaphragmatic hernia may be a Congenital Diaphragmatic Hernia [CDH] lately manifested as a sequela to an iatrogenic intervention or prolonged infections. We aim to explore the genetic correlations in "adult-onset" CDH, with an insight into the indirect contribution of the COVID-19 pandemic towards the fatal outcome.In this report, we present a case of an adult female who died from the complications of an undiagnosed adult-onset diaphragmatic hernia, deemed completely preventable, if not for the global COVID-19 pandemic. There was no prior history of physical trauma or medical history of any relevance.Early diagnosis and rapid surgical intervention remain the keystone management for successfully treating individuals affected by this entity. The decedent in question presented with symptoms demanding hospital stay for investigations that would have aided in timely diagnosis and prevented death. However, the excessive fear of COVID-19 prevented the patient from undergoing hospitalization and follow-up, delaying the diagnosis and leading to death.