Biomedical subjects

Michael Prinz

Publications and source records attributed to Michael Prinz.

4 recordsLinked to original sources

PubMed2006

Automated measurement of skin prick tests: an advance towards exact calculation of wheal size.

BACKGROUND: Using the Khoros image processing software environment, we developed a software-based system capable of extracting wheal size from skin prick tests (SPTs) in mm(2) for research and routine purposes. METHODS: At 20 min, the outlines of up to 20 wheals were marked with a pen and transferred with translucent adhesive tapes to a white paper form carrying predefined markings. The form was scanned at 200 dpi. The software automatically analysed the scanned image and calculated the sizes of the wheals. In a pilot study, serial SPTs with histamine in increasing dilutions were performed in 12 healthy volunteers in duplicate on both volar forearms. We matched the application results with a reference created from the scanned pictures. RESULTS: Bland-Altman analysis showed reference and software calculation reaching very high agreement. The comparison of reference/software resulted in a low centred coefficient of variation (COV) of 11.9%. This was superior to the conventional measurement of horizontal (COV 37.9%) or maximal/minimal diameter (COV 25.9%). CONCLUSION: We present an accurate tool for exactly calculating SPT wheal size in mm(2).

Adult↗

PubMed2005

The JAVA-based DICOM query interface DicoSE.

DICOM 3 is a very elaborate standard for the communication between medical image devices. It is published in several parts by the National Electrical Manufacturers Association (NEMA). To adequately visualize the data structure defined in parts 3, 5 and 6 of the DICOM standard, we implemented the web based Dicom Search Engine (DicoSE). It allows for querying the DICOM standard data dictionary for defined data fields and visualizes the topology of the data which is inherently present in DICOM datasets. For the administration of the underlying data a web based administration interface is provided. The service is entirely based on freely available software.

Information Storage and Retrieval↗

PubMed2005

Automatic measurement of skin wheals provoked by skin prick tests.

Skin prick tests (SPT) represent the standard method for the diagnosis of type-1 allergies. The skin wheals provoked by the SPTs are considered positive above certain cut-off diameters, usually 3 mm. At present their size is mostly estimated by measuring the diameter with rulers. Since the shape of wheals usually is not circular, the measurement of diameters leads to imprecise results. Therefore, we developed an algorithm for precisely measuring the wheals' area in mm(2) automatically. The average deviation of the automatic measurement on a test set achieved with the developed algorithm was 6.9 %. Compared to the maximum standard deviation of 6.59 % when measuring the manually redrawn outlines, the automatic method works sufficiently well.

Algorithms↗

PubMed2003

DicoSE--a Web-interface based on XML for visualizing and searching the topology of the data structure defined by the DICOM 3 standard.

To adequately visualize and interpret the data fields of DICOM 3 datasets the data structure defined in the DICOM 3 standard has to be applied. The DICOM 3 data structure is very extensive and therefore costly to implement. We are working on an open source system which provides the data structure via a Java-programming interface. The data is held in a freely available XML-database. As a spin-off we are providing the web-based Dicom Search Engine (DicoSE) which will be available via internet soon. DicoSE allows for searching the DICOM standard data dictionary for defined data fields and visualizes the topology of the data which is present in DICOM datasets acquired by various types of modalities. Thus, the interpretation of the meaning of data fields is supported. For maintaining the data stored in the database a web-based administration interface is provided.

Database Management Systems↗