Advanced Postprocessing and the Emerging Role of Computer-Aided Detection

Establishing and Leading a 3D Postprocessing Radiology Lab: A Managerial and Leadership Perspective

The rapid acquisition of larg volumes of thin-section CT images has created a considerable need and interest for 3D postprocessing during the interpretation of medical imaging. As a result of the increasing number of postprocessing applications, requiring diagnostic radiologists to perform postprocessing is no longer realistic. This article is a comprehensive review of medical resources regarding establishing a postprocessing radiology laboratory. Besides, leadership and managerial aspects have been covered through a professional business lens. In large-volume settings, a dedicated 3D postprocessing lab ensures the quality, reproducibility, and efficiency of images. Adequate staffing is necessary to fulfill the postprocessing requirements. Educational and experience requirements for 3D technologists may vary among different running laboratories. To evaluate the establishment and running of a 3D lab, it is beneficial to implement diagnostic radiology cost-effectiveness tools. Although establishing a 3D lab has many benefits, certain challenges should be considered. Outsourcing or offshoring may serve as alternatives for establishing a postprocessing laboratory. Building and operating a 3D lab is a significant change in healthcare facilities, and it is crucial for organizations to be aware of the strong resistance toward alternatives the status quo, known as the status quo trap. The change process has essential steps, and skipping the steps creates an illusion of speed but never produces satisfactory results. The organization should ensure the engagement of all interested parties in the whole process. Moreover, a clear vision and proper communication of the vision are vital, and it is crucial to value small wins and ensure expectation clarity in leading the lab during the process.

Assessment of immunotherapy response in intracranial malignancy using semi-automatic segmentation on magnetic resonance images

Objective

To explore multi-aspect radiologic assessment of immunotherapy response in intracranial malignancies based on a semi-automatic segmentation technique, and to explore volumetric thresholds with good performance according to RECIST 1.1 thresholds.

Methods

Patients diagnosed with intracranial malignancies and treated with immunotherapy were included retrospectively. In all MR images, target lesions were measured using a semi-automatic segmentation technique that could intelligently generate visual diagrams including RECIST 1.1, total volume, and max. 3D diameter. The changes in parameters were calculated for each patient after immunotherapy. The ROC curve was used to analyze the sensitivity and specificity of the size change of the legion. This was useful to find new volumetric thresholds with better efficiency in response assessment. The changes in total volume were assessed by conventional volumetric thresholds, while RECIST 1.1 thresholds were for the max. 3D diameter. A chi-square test was used to compare the concordance and diagnostic correlation between the response assessment results of the three criteria.

Results

A total of 20 cases (average age, 58 years; range, 23 to 84 years) and 58 follow-up MR examinations after immunotherapy were included in the analysis. The P-value of the chi-square test between RECIST 1.1 and total volume is 0 (P <0.05), same as that in RECIST 1.1 and max. 3D diameter. The kappa value of the former two was 0.775, and the kappa value for the latter two was 0.742. The above results indicate a significant correlation and good concordance for all three criteria. In addition, we also found that the volumetric assessment had the best sensitivity and specificity for the immunotherapy response in intracranial malignancies, with a PR threshold of -64.9% and a PD threshold of 21.4%.

Conclusions

Radiologic assessment of immunotherapy response in intracranial malignancy can be performed by multiple criteria based on semi-automatic segmentation technique on MR images, such as total volume, max. 3D diameter and RECIST 1.1. In addition, new volumetric thresholds with good sensitivity and specificity were found by volumetric assessment.

The current and possible future role of 3D modelling within oesophagogastric surgery: a scoping review

BACKGROUND

3D reconstruction technology could revolutionise medicine. Within surgery, 3D reconstruction has a growing role in operative planning and procedures, surgical education and training as well as patient engagement. Whilst virtual and 3D printed models are already used in many surgical specialities, oesophagogastric surgery has been slow in their adoption. Therefore, the authors undertook a scoping review to clarify the current and future roles of 3D modelling in oesophagogastric surgery, highlighting gaps in the literature and implications for future research.

METHODS

A scoping review protocol was developed using a comprehensive search strategy based on internationally accepted guidelines and tailored for key databases (MEDLINE, Embase, Elsevier Scopus and ISI Web of Science). This is available through the Open Science Framework (osf.io/ta789) and was published in a peer-reviewed journal. Included studies underwent screening and full text review before inclusion. A thematic analysis was performed using pre-determined overarching themes: (i) surgical training and education, (ii) patient education and engagement, and (iii) operative planning and surgical practice. Where applicable, subthemes were generated.

RESULTS

A total of 56 papers were included. Most research was low-grade with 88% (n = 49) of publications at or below level III evidence. No randomised control trials or systematic reviews were found. Most literature (86%, n = 48) explored 3D reconstruction within operative planning. These were divided into subthemes of pre-operative (77%, n = 43) and intra-operative guidance (9%, n = 5). Few papers reported on surgical training and education (14%, n = 8), and were evenly subcategorised into virtual reality simulation (7%, n = 4) and anatomical teaching (7%, n = 4). No studies utilising 3D modelling for patient engagement and education were found.

CONCLUSION

The use of 3D reconstruction is in its infancy in oesophagogastric surgery. The quality of evidence is low and key themes, such as patient engagement and education, remain unexplored. Without high quality research evaluating the application and benefits of 3D modelling, oesophagogastric surgery may be left behind.

Airway Evaluation with Multidetector Computed Tomography Post-Processing Methods in Asthmatic Patients

Asthma is a chronic inflammatory obstructive airways disease. The disease occurs regardless of age and manifests with cough, attacks of breathlessness, and tightness in the chest. The pathophysiology of asthma is complex and still not fully understood. It is essential to find answers concerning the role of each part of the bronchial tree in asthma, especially the role of small bronchioles. With the development of newer generations of multidetector computed tomography (MDCT) and advanced post-processing methods it is possible to obtain more detailed images and gain insight into further aspects of asthma. MDCT post-processing methods can be divided into two-dimensional (2D) and three-dimensional (3D). In 2D projections, visualized hypodense regions correspond to the airway flow limitations. With the more advanced methods, such as multi planar reconstructions (MPR), images in different planes (axial, coronal, or sagittal) can be created. In the MPR technique only the voxels which are adjacent to each other in the predetermined plane can be extracted from the data set. Using the minimal/maximal intensity projections and shaded surface display, the volume of interest (VOI) can be extracted. High resolution CT scans can be used to create a more advanced imaging tool - the virtual bronchoscopy (VB). Using the VB makes it possible to visualize regions of obturation in the bronchi of up to the 5-8th generation. The MDCT with advanced post-processing methods is likely to assume an important role in the differential diagnosis of asthma, particularly when the diagnosis is dubious or hard to settle due to accompanying other lung diseases.