28 Contribution of transit dosimetry (EPID-based) and retrospective dose calculation in the patient’s real anatomy (kV-CBCT-based) for the estimation of the dose delivered to the patient (Preliminary study)

2018 ◽  
Vol 56 ◽  
pp. 52-53
Author(s):  
R. Sauvinet ◽  
C. Chevillard ◽  
F. Husson ◽  
N. Pierrat ◽  
J-L. Dumas
Keyword(s):  
Dose Calculation ◽  
Preliminary Study ◽  
Transit Dosimetry

scholarly journals MRI-based Treatment Planning with Electron Density Information Mapped from CT Images: A Preliminary Study

2008 ◽  
Vol 7 (5) ◽  
pp. 341-347 ◽  
Author(s):  
C. Wang ◽  
M. Chao ◽  
L. Lee ◽  
L. Xing
Keyword(s):  
Electron Density ◽  
Radiation Treatment ◽  
Dose Calculation ◽  
Ct Images ◽  
Planar Imaging ◽  
Mr Images ◽  
Dosimetric Accuracy ◽  
Tissue Contrast ◽  
Preliminary Study ◽  
Ct Data

Nowadays magnetic resonance imaging (MRI) has been profoundly used in radiotherapy (RT) planning to aid the contouring of targets and critical organs in brain and intracranial cases, which is attributable to its excellent soft tissue contrast and multi-planar imaging capability. However, the lack of electron density information in MRI, together with the image distortion issues, precludes its use as the sole image set for RT planning and dose calculation. The purpose of this preliminary study is to probe the feasibility and evaluate an MRI-based radiation dose calculation process by providing MR images the necessary electron density (ED) information from a patient's readily available diagnostic/staging computed tomography (CT) images using an image registration model. To evaluate the dosimetric accuracy of the proposed approach, three brain and three intracranial cases were selected retrospectively for this study. For each patient, the MR images were registered to the CT images, and the ED information was then mapped onto the MR images by in-house developed software generating a modified set of MR images. Another set of MR images with voxel values assigned with the density of water was also generated. The original intensity modulated radiation treatment (IMRT) plan was then applied to the two sets of MR images and the doses were calculated. The dose distributions from the MRI-based calculations were compared to that of the original CT-based calculation. In all cases, the MRI-based calculations with mapped ED yielded dose values very close (within 2%) to that of the CT-based calculations. The MRI-based calculations with voxel values assigned with water density indicated a dosimetric error of 3–5%, depending on the treatment site. The present approach offers a means of utilizing MR images for accurate dose calculation and affords a potential to eliminate the redundant simulation CT by planning a patient's treatment with only simulation MRI and any available diagnostic/staging CT data.

The Ultrastructure of Metastatic Human Mammary Carcinoma After Prolonged Estrogen Therapy

1967 ◽  
Vol 25 ◽  
pp. 180-181
Author(s):  
John H.L. Watson ◽  
John L. Swedo ◽  
R.W. Talley
Keyword(s):  
Mammary Carcinoma ◽  
Osmium Tetroxide ◽  
Estrogen Therapy ◽  
Ultrastructural Level ◽  
Uranyl Acetate ◽  
Human Mammary Carcinoma ◽  
Surgical Biopsy ◽  
Lead Hydroxide ◽  
Preliminary Study ◽  
Hormonal Therapies

A preliminary study of human mammary carcinoma on the ultrastructural level is reported for a metastatic, subcutaneous nodule, obtained as a surgical biopsy. The patient's tumor had responded favorably to a series of hormonal therapies, including androgens, estrogens, progestins, and corticoids for recurring nodules over eight years. The pertinent nodule was removed from the region of the gluteal maximus, two weeks following stilbestrol therapy. It was about 1.5 cms in diameter, and was located within the dermis. Pieces from it were fixed immediately in cold fixatives: phosphate buffered osmium tetroxide, glutaraldehyde, and paraformaldehyde. Embedment in each case was in Vestopal W. Contrasting was done with combinations of uranyl acetate and lead hydroxide.

Fine structure of early degenerating myofibers in the tibialis anterior of young ‘MDX’ mouse

1988 ◽  
Vol 46 ◽  
pp. 322-323
Author(s):  
H.D. Geissinger ◽  
C.K. McDonald-Taylor
Keyword(s):  
Fine Structure ◽  
Muscle Regeneration ◽  
Tibialis Anterior ◽  
Genetic Defect ◽  
Mdx Mouse ◽  
Mdx Mice ◽  
Histopathological Changes ◽  
Electron Microscopic ◽  
Dystrophic Mouse ◽  
Preliminary Study

A new strain of mice, which had arisen by mutation from a dystrophic mouse colony was designated ‘mdx’, because the genetic defect, which manifests itself in brief periods of muscle destruction followed by episodes of muscle regeneration appears to be X-linked. Further studies of histopathological changes in muscle from ‘mdx’ mice at the light microscopic or electron microscopic levels have been published, but only one preliminary study has been on the tibialis anterior (TA) of ‘mdx’ mice less than four weeks old. Lesions in the ‘mdx’ mice vary between different muscles, and centronucleation of fibers in all muscles studied so far appears to be especially prominent in older mice. Lesions in young ‘mdx’ mice have not been studied extensively, and the results appear to be at variance with one another. The degenerative and regenerative aspects of the lesions in the TA of 23 to 26-day-old ‘mdx’ mice appear to vary quantitatively.

Ultrastructural observations of the aorta of calves implanted with a mechanical left ventricular assist device

1990 ◽  
Vol 48 (3) ◽  
pp. 834-835
Author(s):  
J P Cassella ◽  
V Salih ◽  
T R Graham
Keyword(s):  
Left Ventricular Assist Device ◽  
Ventricular Assist Device ◽  
Left Ventricular ◽  
Aortic Tissue ◽  
Assist Device ◽  
Ventricular Assist ◽  
Transmission Electron ◽  
Left Ventricular Assist ◽  
Preliminary Study

Left ventricular assist systems are being developed for eventual long term or permanent implantation as an alternative to heart transplantation in patients unsuitable for or denied the transplant option. Evaluation of the effects of these devices upon normal physiology is required. A preliminary study was conducted to evaluate the morphology of aortic tissue from calves implanted with a pneumatic Left Ventricular Assist device-LVAD. Two 3 month old heifer calves (calf 1 and calf 2) were electively explanted after 128 days and 47 days respectively. Descending thoracic aortic tissue from both animals was removed immediately post mortem and placed into karnovsky’s fixative. The tissue was subsequently processed for transmission electron microscopy (TEM). Some aortic tissue was fixed in neutral buffered formalin and processed for routine light microscopy.

A preliminary study on the potential of front face fluorescence spectroscopy for the discrimination of Moroccan virgin olive oils and the prediction of their quality

2021 ◽  
Author(s):  
Hicham Zaroual ◽  
El Mestafa El Hadrami ◽  
Romdhane Karoui
Keyword(s):  
Fluorescence Spectroscopy ◽  
Olive Oil ◽  
Virgin Olive Oil ◽  
Front Face ◽  
Virgin Olive Oils ◽  
Olive Oils ◽  
Preliminary Study

This study examines the feasibility of using front face fluorescence spectroscopy (FFFS) to authenticate 41 virgin olive oil (VOO) samples collected from 5 regions in Morocco during 2 consecutive crop seasons.

Dysarthria Profiles in Adults With Hereditary Ataxia

2019 ◽  
Vol 28 (2S) ◽  
pp. 915-924 ◽  
Author(s):  
Kristie A. Spencer ◽  
Mallory Dawson
Keyword(s):  
Rating Scales ◽  
Feedforward Control ◽  
Hereditary Ataxia ◽  
Severity Rating ◽  
Visual Analog Scales ◽  
Speech Characteristics ◽  
Ataxic Dysarthria ◽  
Preliminary Study

Purpose This preliminary study examined whether speech profiles exist for adults with hereditary ataxia based on 2 competing frameworks: a pattern of instability/inflexibility or a pattern of differential subsystem involvement. Method Four dysarthria experts rated the speech samples of 8 adults with dysarthria from hereditary ataxia using visual analog scales and presence/severity rating scales of speech characteristics. Speaking tasks included diadochokinetics, sustained phonation, and a monologue. Results Speech profiles aligned with the instability/inflexibility framework, with the pattern of instability being the most common. Speech profiles did not emerge for the majority of speakers using the differential subsystem framework. Conclusions The findings extend previous research on pure ataxic dysarthria and suggest a possible framework for understanding the speech heterogeneity associated with the ataxias. The predominance of the instability profile is consistent with the notion of impaired feedforward control in speakers with cerebellar disruption.

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