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Evaluation of Volumetric Change of Intracerebral Hemorrhage in Patients Treated with Thrombolysis for Intraventricular Hemorrhage.

PubMED - dom, 08/02/2020 - 09:01
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Evaluation of Volumetric Change of Intracerebral Hemorrhage in Patients Treated with Thrombolysis for Intraventricular Hemorrhage.

Neurocrit Care. 2020 Jul 31;:

Authors: Staub-Bartelt F, van Lieshout JH, Beez T, Kram R, Hänggi D, Besoglu K

Abstract
BACKGROUND: Intraventricular hemorrhage (IVH) is often caused by irruption of intracerebral hemorrhage (ICH) of basal ganglia or thalamus into the ventricular system. Instillation of recombinant tissue plasminogen activator (rtPA) via an external ventricular drainage (EVD) has been shown to effectively decrease IVH volumes while the impact of rtPA instillation on ICH volumes remains unclear. In this series, we analyzed volumetric changes of ICH in patients with and without intrathecal lysis therapy.
METHODS: Between 01/2013 and 01/2019, 36 patients with IVH caused by hemorrhage of basal ganglia, thalamus or brain stem were treated with rtPA via an EVD (Group A). Initial volumes were determined in the first available computed tomography (CT) scan, final volumes in the last CT scan before discharge. During the same period, 41 patients with ICH without relevant IVH were treated without intrathecal lysis therapy at our neurocritical care unit (Group B). Serial CT scans were evaluated separately for changes in ICH volumes for both cohorts using OsiriX DICOM viewer. The Wilcoxon signed-rank test was performed for statistical analysis in not normally distributed variables.
RESULTS: Median initial volume of ICH for treatment Group A was 6.5 ml and was reduced to 5.0 ml after first instillation of rtPA (p < 0.01). Twenty-six patients received a second treatment with rtPA (ICH volume reduction 4.5 to 3.3 ml, p < 0.01) and of this cohort further 16 patients underwent a third treatment (ICH volume reduction 3.0 ml to 1.5 ml, p < 0.01). Comparison of first and last CT scan in Group A confirmed an overall median percentage reduction of 91.7% (n = 36, p < 0.01) of ICH volumes and hematoma resolution in Group A was significantly more effective compared to non-rtPA group, Group B (percentage reduction = 68%) independent of initial hematoma volume in the regression analysis (p = 0.07, mean 11.1, 95%CI 7.7-14.5). There were no adverse events in Group A related to rtPA instillation.
CONCLUSION: Intrathecal lysis therapy leads to a significant reduction in the intraparenchymal hematoma volume with faster clot resolution compared to the spontaneous hematoma resorption. Furthermore, intrathecal rtPA application had no adverse effect on ICH volume.

PMID: 32737761 [PubMed - as supplied by publisher]

Contralateral adrenal thinning as a distinctive feature of mild autonomous cortisol excess of the adrenal tumors.

PubMED - ter, 07/28/2020 - 08:17

Contralateral adrenal thinning as a distinctive feature of mild autonomous cortisol excess of the adrenal tumors.

Eur J Endocrinol. 2020 Sep;183(3):325-333

Authors: Kong SH, Kim JH, Shin CS

Abstract
Objective: To identify radiologic features that correlate with mild autonomous cortisol excess using planar and volumetric analysis.
Design: Cross-sectional study.
Methods: In the study, 64 patients with overt Cushing syndrome (CS), 59 patients with mild autonomous cortisol excess (MACE), and 64 patients with nonfunctioning adrenal tumors (NFAT) with evaluable CT scans were included. Patients with NFAT and MACE were BMI-matched with those with overt CS. Planar and volumetric analyses of CT scans were performed in DICOM images using OsiriX software.
Results: The mean age was 56.6 ± 1.01 years, and 123 patients (65.1%) were female. In the order of NFAT, MACE, and overt CS, the diameters and volumes of the adenoma increased, while limb widths and volumes of the contralateral adrenal gland decreased. Patients with MACE or overt CS were more likely to have osteoporosis than those with NFAT (P = 0.006), and patients with overt CS were more likely to experience a fragility fracture than those with NFAT or MACE (P = 0.002). Among radiologic features, the limb width of the contralateral adrenal gland correlated with the cortisol level after overnight dexamethasone suppression test (r = -0.583, P < 0.001).
Conclusions: The study showed that the contralateral adrenal limb thinning was a distinctive radiologic feature of autonomous cortisol excess in the planar and volumetric analysis.

PMID: 32717717 [PubMed - as supplied by publisher]

MRI based volumetric measurements of vestibular schwannomas in patients with neurofibromatosis type 2: comparison of three different software tools.

PubMED - qui, 07/16/2020 - 09:16
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MRI based volumetric measurements of vestibular schwannomas in patients with neurofibromatosis type 2: comparison of three different software tools.

Sci Rep. 2020 Jul 14;10(1):11541

Authors: Kollmann P, Mautner VF, Koeppen J, Wenzel R, Friedman JM, Salamon J, Farschtschi S

Abstract
Neurofibromatosis type 2 is a neurogenetic disorder with an incidence of about 1:33.000. Hallmarks are bilateral benign vestibular schwannomas, which can lead to deafness or brainstem compression. Volumetric tumor measurements are essential to assess the efficacy of new therapies. We present a statistical and methodical comparison of three volumetric image analysis tools. We performed volumetric measurements on phantoms with predefined volumes (0.1 to 8.0 ml) and tumors seen on 32 head MRI scans from eight NF2 patients with BrainLab, ITK-Snap, or OsiriX. The software was compared with regard to accuracy and reproducibility of the measurements and time required for analysis. The mean volume estimated by all three software programs differed significantly from the true volume of the phantoms, but OsiriX and BrainLab gave estimates that were not significantly different from each other. For the actual tumors, the estimated volumes with all three software tools showed a low coefficient of variability, but the mean volume estimates differed among the tools. OsiriX showed the shortest analysis time. Volumetric assessment of MRI images is associated to an intrinsic risk of miscalculation. For precise volumes it is mandatory to use the same volumetric tools for all measurements.

PMID: 32665659 [PubMed - in process]

Quantification of Nasal Septal Deviation With Computed Tomography Data.

PubMED - sab, 06/06/2020 - 09:12
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Quantification of Nasal Septal Deviation With Computed Tomography Data.

J Craniofac Surg. 2020 Jun 04;:

Authors: Denour E, Roussel LO, Woo AS, Boyajian M, Crozier J

Abstract
BACKGROUND: Despite extensive literature on the classification and management of nasal septal deviation (NSD) for preoperative planning, standardized objective measures to evaluate the NSD severity remains challenging. In this study, we quantitatively analyzed NSD to determine the most predictive two-dimensional (2D) computed tomography (CT)-landmark for overall three-dimensional (3D) septal morphology derived from nasal airway segmentation.
METHODS: A retrospective study was conducted at a large academic center. One hundred four patients who underwent CT scans of the face were selected from a computer imaging database. Demographic variables were screened to ensure an equal number of men and women in different age groups. Digital Imaging and Communications in Medicine files were imported for 3D nasal cavity segmentation using 3D Slicer software. A volumetric analysis was performed to determine 3D NSD ratios. These values were compared to previously reported methods of obtaining objective 2D NSD measures using OsiriX and MATLAB software. Maximum deviation values were calculated using OsiriX, while the root mean square values were retrieved using MATLAB. Deviation area and curve to line ratios were both quantified using OsiriX and MATLAB.
RESULTS: The data set consisted of 52 men and 52 women patients aged 20 to 100 years (mean = 58 years, standard deviation = 23 years). There was a strong correlation between 3D NSD ratio and maximum deviation (r = 0.789, P < 0.001) and deviation area (r = 0.775, P < 0.001). Deviation area (r = 0.563, P < 0.001), root mean square (r = 0.594, P < 0.001), and curve to line ratio (r = 0.470, P < 0.001) had a positive correlation of moderate strength. The curve to line ratio was not significant (r = 0.019, P = 0.85).
CONCLUSIONS: The 2D CT-based NSD landmarks maximum deviation and deviation area were the most predictive of the severity of NSD from 3D nasal cavity segmentation. We present a robust open-source method that may be useful in predicting the severity of NSD in CT images.

PMID: 32502103 [PubMed - as supplied by publisher]

"STUDY ON PREDICTING THE IDEAL VENTRICULAR FREEHAND PASS TRAJECTORY USING OSIRIX SOFTWARE AND THE ROLE OF OCCIPITAL SHAPE VARIATIONS."

PubMED - qua, 05/27/2020 - 07:46

"STUDY ON PREDICTING THE IDEAL VENTRICULAR FREEHAND PASS TRAJECTORY USING OSIRIX SOFTWARE AND THE ROLE OF OCCIPITAL SHAPE VARIATIONS."

World Neurosurg. 2020 May 23;:

Authors: Deora H, Pruthi N, Rao KVLN, Saini J, Dikshit P

PMID: 32454198 [PubMed - as supplied by publisher]

MRI perfusion analysis using freeware, standard imaging software.

PubMED - qua, 05/20/2020 - 10:02
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MRI perfusion analysis using freeware, standard imaging software.

BMC Vet Res. 2020 May 18;16(1):141

Authors: Hartmann A, Scholz VB, Lautenschläger IE

Abstract
BACKGROUND: Perfusion-weighted imaging is only scarcely used in veterinary medicine. The exact reasons are unclear. One reason might be the typically high costs of the software packages for image analysis. In addition, a great variability concerning available programs makes it hard to compare results between different studies. Moreover, these algorithms are tuned for their usage in human medicine and often difficult to adapt to veterinary studies. In order to address these issues, our aim is to deliver a free open source package for calculating quantitative perfusion parameters. We develop an "R package" calculating mean transit time, cerebral blood flow and cerebral blood volume from data obtained with freely imaging software (OsiriX Light®). We hope that the free availability, in combination with the fact that the underlying algorithm is open and adaptable, makes it easier for scientists in veterinary medicine to use, compare and adapt perfusion-weighted imaging analysis. In order to demonstrate the usage of our software package, we reviewed previously acquired perfusion-weighted images from a group of eight purpose-breed healthy beagle dogs and twelve client-owned dogs with idiopathic epilepsy. In order to obtain the data needed for our algorithm, the following steps were performed: First, regions of interest (ROI) were drawn around different, previously reported, brain regions and the middle cerebral artery. Second, a ROI enhancement curve was generated for each ROI using a freely available PlugIn. Third, the signal intensity curves were exported as a comma-separated-value file. These files constitute the input to our software package, which then calculates the PWI parameters.
RESULTS: We used our software package to re-assess perfusion weighted images from two previous studies. The clinical results were similar, showing a significant increase in the mean transit time and a significant decrease in cerebral blood flow for diseased dogs.
CONCLUSION: We provide an "R package" for computing the main perfusion parameters from measurements taken with standard imaging software and describe in detail how to obtain these measurements. We hope that our contribution enables users in veterinary medicine to easily obtain perfusion parameters using standard Open Source software in a standard, adaptable and comparable way.

PMID: 32423403 [PubMed - in process]

Open Health Imaging Foundation Viewer: An Extensible Open-Source Framework for Building Web-Based Imaging Applications to Support Cancer Research.

PubMED - sex, 04/24/2020 - 09:18

Open Health Imaging Foundation Viewer: An Extensible Open-Source Framework for Building Web-Based Imaging Applications to Support Cancer Research.

JCO Clin Cancer Inform. 2020 Apr;4:336-345

Authors: Ziegler E, Urban T, Brown D, Petts J, Pieper SD, Lewis R, Hafey C, Harris GJ

Abstract
PURPOSE: Zero-footprint Web architecture enables imaging applications to be deployed on premise or in the cloud without requiring installation of custom software on the user's computer. Benefits include decreased costs and information technology support requirements, as well as improved accessibility across sites. The Open Health Imaging Foundation (OHIF) Viewer is an extensible platform developed to leverage these benefits and address the demand for open-source Web-based imaging applications. The platform can be modified to support site-specific workflows and accommodate evolving research requirements.
MATERIALS AND METHODS: The OHIF Viewer provides basic image review functionality (eg, image manipulation and measurement) as well as advanced visualization (eg, multiplanar reformatting). It is written as a client-only, single-page Web application that can easily be embedded into third-party applications or hosted as a standalone Web site. The platform provides extension points for software developers to include custom tools and adapt the system for their workflows. It is standards compliant and relies on DICOMweb for data exchange and OpenID Connect for authentication, but it can be configured to use any data source or authentication flow. Additionally, the user interface components are provided in a standalone component library so that developers can create custom extensions.
RESULTS: The OHIF Viewer and its underlying components have been widely adopted and integrated into multiple clinical research platforms (e,g Precision Imaging Metrics, XNAT, LabCAS, ISB-CGC) and commercial applications (eg, Osirix). It has also been used to build custom imaging applications (eg, ProstateCancer.ai, Crowds Cure Cancer [presented as a case study]).
CONCLUSION: The OHIF Viewer provides a flexible framework for building applications to support imaging research. Its adoption could reduce redundancies in software development for National Cancer Institute-funded projects, including Informatics Technology for Cancer Research and the Quantitative Imaging Network.

PMID: 32324447 [PubMed - as supplied by publisher]

Video-based augmented reality combining CT-scan and instrument position data to microscope view in middle ear surgery.

PubMED - qui, 04/23/2020 - 09:15
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Video-based augmented reality combining CT-scan and instrument position data to microscope view in middle ear surgery.

Sci Rep. 2020 Apr 21;10(1):6767

Authors: Hussain R, Lalande A, Marroquin R, Guigou C, Bozorg Grayeli A

Abstract
The aim of the study was to develop and assess the performance of a video-based augmented reality system, combining preoperative computed tomography (CT) and real-time microscopic video, as the first crucial step to keyhole middle ear procedures through a tympanic membrane puncture. Six different artificial human temporal bones were included in this prospective study. Six stainless steel fiducial markers were glued on the periphery of the eardrum, and a high-resolution CT-scan of the temporal bone was obtained. Virtual endoscopy of the middle ear based on this CT-scan was conducted on Osirix software. Virtual endoscopy image was registered to the microscope-based video of the intact tympanic membrane based on fiducial markers and a homography transformation was applied during microscope movements. These movements were tracked using Speeded-Up Robust Features (SURF) method. Simultaneously, a micro-surgical instrument was identified and tracked using a Kalman filter. The 3D position of the instrument was extracted by solving a three-point perspective framework. For evaluation, the instrument was introduced through the tympanic membrane and ink droplets were injected on three middle ear structures. An average initial registration accuracy of 0.21 ± 0.10 mm (n = 3) was achieved with a slow propagation error during tracking (0.04 ± 0.07 mm). The estimated surgical instrument tip position error was 0.33 ± 0.22 mm. The target structures' localization accuracy was 0.52 ± 0.15 mm. The submillimetric accuracy of our system without tracker is compatible with ear surgery.

PMID: 32317726 [PubMed - in process]

Introducing a new method for classifying skull shape abnormalities related to craniosynostosis.

PubMED - dom, 04/19/2020 - 08:38
Related Articles

Introducing a new method for classifying skull shape abnormalities related to craniosynostosis.

Eur J Pediatr. 2020 Apr 17;:

Authors: Kronig ODM, Kronig SAJ, Vrooman HA, Veenland JF, Jippes M, Boen T, Van Adrichem LNA

Abstract
We present a novel technique for classification of skull deformities due to most common craniosynostosis. We included 5 children of every group of the common craniosynostoses (scaphocephaly, brachycephaly, trigonocephaly, and right- and left-sided anterior plagiocephaly) and additionally 5 controls. Our outline-based classification method is described, using the software programs OsiriX, MeVisLab, and Matlab. These programs were used to identify chosen landmarks (porion and exocanthion), create a base plane and a plane at 4 cm, segment outlines, and plot resulting graphs. We measured repeatability and reproducibility, and mean curves of groups were analyzed. All raters achieved excellent intraclass correlation scores (0.994-1.000) and interclass correlation scores (0.989-1.000) for identifying the external landmarks. Controls, scaphocephaly, trigonocephaly, and brachycephaly all have the peak of the forehead in the middle of the curve (180°). In contrary, in anterior plagiocephaly, the peak is shifted (to the left of graph in right-sided and vice versa). Additionally, controls, scaphocephaly, and trigonocephaly have a high peak of the forehead; scaphocephaly has the lowest troughs; in brachycephaly, the width/frontal peak ratio has the highest value with a low frontal peak.Conclusion: We introduced a preliminary study showing an objective and reproducible methodology using CT scans for the analysis of craniosynostosis and potential application of our method to 3D photogrammetry.What is Known:• Diagnosis of craniosynostosis is relatively simple; however, classification of craniosynostosis is difficult and current techniques are not widely applicable.What is New:• We introduce a novel technique for classification of skull deformities due to craniosynostosis, an objective and reproducible methodology using CT scans resulting in characteristic curves. The method is applicable to all 3D-surface rendering techniques.• Using external landmarks and curve analysis, specific and characteristic curves for every type of craniosynostosis related to the specific skull deformities are found.

PMID: 32303825 [PubMed - as supplied by publisher]