Hard disk online caches in picture archiving and communication systems archives: how big is beautiful?

The retention duration of digital images in picture archiving and communication systems

Introduction

Every year, a large number of medical images such as MRIs, CT scans, and radiographs are prepared in hospitals, and a lot of money is spent on their preparation. Picture archiving and communication system (PACS) is an integrated image management system for maintaining and storing digital images. The objective of this study was to determine the storage duration of digital images in PACS.

Methods

This was a scoping review study in which we searched the PubMed and Embase databases using a combination of terms related to radiography, storage, and duration. The reference lists of included articles were checked to identify other relevant articles. Moreover, we searched Google to retrieve relevant gray literature and other information sources including guidelines. The selection process was carried out in three stages and was reported based on the PRISMA flowchart and the data were extracted using the data collection form.

Results

Based on the database search 2867 articles were identified, of which 13 articles were eligible for inclusion. Searching for gray literature identified 7 relevant sources. The results showed that based on the institutions' plans and regulations, different countries have different storage policies. In general, to store images between 6 and 240 months for short-term storage and between 0 and 240 months for long-term storage were considered.

Conclusion

Due to financial constraints and storage space requirements, healthcare organizations can provide a solution by drafting guidelines on the appropriate storage duration for medical images. The findings of this study can assist healthcare authorities and healthcare centers in employing PACS systems to manage and minimize storage space for medical images, thereby reducing storage costs.

An Intelligent Cloud Storage Gateway for Medical Imaging

Historically, medical imaging repositories have been supported by indoor infrastructures. However, the amount of diagnostic imaging procedures has continuously increased over the last decades, imposing several challenges associated with the storage volume, data redundancy and availability. Cloud platforms are focused on delivering hardware and software services over the Internet, becoming an appealing solution for repository outsourcing. Although this option may bring financial and technological benefits, it also presents new challenges. In medical imaging scenarios, communication latency is a critical issue that still hinders the adoption of this paradigm. This paper proposes an intelligent Cloud storage gateway that optimizes data access times. This is achieved through a new cache architecture that combines static rules and pattern recognition for eviction and prefetching. The evaluation results, obtained from experiments over a real-world dataset, show that cache hit ratios can reach around 80%, leading to reductions of image retrieval times by over 60%. The combined use of eviction and prefetching policies proposed can significantly reduce communication latency, even when using a small cache in comparison to the total size of the repository. Apart from the performance gains, the proposed system is capable of adjusting to specific workflows of different institutions.

DICOM data migration for PACS transition: procedure and pitfalls

PURPOSE

Transition from one Picture Archiving and Communication System (PACS) to the other is costly and disruptive. Especially the migration of the DICOM data from the legacy to the new PACS is a very challenging task, and although such a migration will happen in every hospital, literature on methodologies to follow and possible problems and pitfalls is scarce. The objective of this work is to provide insight in the prerequisites for the legacy PACS before starting the migration with respect to vendor and DICOM considerations.

METHODS

The steps involved in migration, possible methodologies, and areas of specific interest when planning migration are given. Possible challenges and problems are defined as well as issues that are often overlooked.

RESULTS

A step-wise approach should be implemented for data migration. Careful planning and testing, continuous observation of the process, and involvement of all stakeholders including the old and new vendors are crucial for a successful transition from one PACS to the other.

CONCLUSION

A proper test migration is a crucial step in the PACS transition process, which can eliminate many of the problems in the actual migration. However, with any migration, there has to be a willingness to take a limited amount of risk since not all problems can nor will be identified in the test migration.

A PACS archive architecture supported on cloud services

PURPOSE

Diagnostic imaging procedures have continuously increased over the last decade and this trend may continue in coming years, creating a great impact on storage and retrieval capabilities of current PACS. Moreover, many smaller centers do not have financial resources or requirements that justify the acquisition of a traditional infrastructure. Alternative solutions, such as cloud computing, may help address this emerging need.

METHODS

A tremendous amount of ubiquitous computational power, such as that provided by Google and Amazon, are used every day as a normal commodity. Taking advantage of this new paradigm, an architecture for a Cloud-based PACS archive that provides data privacy, integrity, and availability is proposed. The solution is independent from the cloud provider and the core modules were successfully instantiated in examples of two cloud computing providers. Operational metrics for several medical imaging modalities were tabulated and compared for Google Storage, Amazon S3, and LAN PACS.

RESULTS

A PACS-as-a-Service archive that provides storage of medical studies using the Cloud was developed. The results show that the solution is robust and that it is possible to store, query, and retrieve all desired studies in a similar way as in a local PACS approach.

CONCLUSION

Cloud computing is an emerging solution that promises high scalability of infrastructures, software, and applications, according to a "pay-as-you-go" business model. The presented architecture uses the cloud to setup medical data repositories and can have a significant impact on healthcare institutions by reducing IT infrastructures.