TY  - JOUR
A1  - Ullherr, Maximilian
A1  - Diez, Matthias
A1  - Zabler, Simon
T1  - Robust image reconstruction strategy for multiscalar holotomography
JF  - Journal of Imaging
N2  - Holotomography is an extension of computed tomography where samples with low X-ray absorption can be investigated with higher contrast. In order to achieve this, the imaging system must yield an optical resolution of a few micrometers or less, which reduces the measurement area (field of view = FOV) to a few mm at most. If the sample size, however, exceeds the field of view (called local tomography or region of interest = ROI CT), filter problems arise during the CT reconstruction and phase retrieval in holotomography. In this paper, we will first investigate the practical impact of these filter problems and discuss approximate solutions. Secondly, we will investigate the effectiveness of a technique we call “multiscalar holotomography”, where, in addition to the ROI CT, a lower resolution non-ROI CT measurement is recorded. This is used to avoid the filter problems while simultaneously reconstructing a larger part of the sample, albeit with a lower resolution in the additional area.
KW  - reconstruction
KW  - region of interest
KW  - ROI
KW  - multiscalar holotomography
KW  - holotomography
KW  - computed tomography
KW  - CT
KW  - X-ray
Y1  - 2022
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-262112
SN  - 2313-433X
VL  - 8
IS  - 2
ER  - 
TY  - JOUR
A1  - Noyalet, Laurent
A1  - Ilgen, Lukas
A1  - Bürklein, Miriam
A1  - Shehata-Dieler, Wafaa
A1  - Taeger, Johannes
A1  - Hagen, Rudolf
A1  - Neun, Tilmann
A1  - Zabler, Simon
A1  - Althoff, Daniel
A1  - Rak, Kristen
T1  - Vestibular aqueduct morphology and Meniere’s disease - development of the vestibular aqueduct score by 3D analysis
JF  - Frontiers in Surgery
N2  - Improved radiological examinations with newly developed 3D models may increase understanding of Meniere's disease (MD). The morphology and course of the vestibular aqueduct (VA) in the temporal bone might be related to the severity of MD. The presented study explored, if the VA of MD and non-MD patients can be grouped relative to its angle to the semicircular canals (SCC) and length using a 3D model. Scans of temporal bone specimens (TBS) were performed using micro-CT and micro flat panel volume computed tomography (mfpVCT). Furthermore, scans were carried out in patients and TBS by computed tomography (CT). The angle between the VA and the three SCC, as well as the length of the VA were measured. From these data, a 3D model was constructed to develop the vestibular aqueduct score (VAS). Using different imaging modalities it was demonstrated that angle measurements of the VA are reliable and can be effectively used for detailed diagnostic investigation. To test the clinical relevance, the VAS was applied on MD and on non-MD patients. Length and angle values from MD patients differed from non-MD patients. In MD patients, significantly higher numbers of VAs could be assigned to a distinct group of the VAS. In addition, it was tested, whether the outcome of a treatment option for MD can be correlated to the VAS.
KW  - vestibular aqueduct (VA)
KW  - 3D analysis
KW  - temporal bone
KW  - saccotomy
KW  - computed tomography
KW  - Meniere’s disease
Y1  - 2022
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-312893
SN  - 2296-875X
VL  - 9
ER  -