A systematic review of synthetic CT generation methodologies for use in MRI-only radiotherapy

Publication date: Available online 8 September 2017
Source:International Journal of Radiation Oncology*Biology*Physics
Author(s): Emily Johnstone, Jonathan J. Wyatt, Ann M. Henry, Susan C. Short, David Sebag-Montefiore, Louise Murray, Charles G. Kelly, Hazel M. McCallum, Richard Speight
MRI offers superior soft tissue contrast as compared to CT, which is conventionally used for radiotherapy treatment planning (RTP) and patient positioning verification, resulting in improved target definition. The two modalities are co-registered for RTP, however this introduces a systematic error. Implementing an MRI-only radiotherapy workflow would be advantageous as this error would be eliminated, the patient pathway simplified and patient dose reduced. Unlike CT, in MRI there is no direct relationship between signal intensity and electron density, however various methodologies for MRI-only RTP have been reported. A systematic review of these methods was undertaken.The PRISMA guidelines(1) were followed. Embase and Medline databases were searched (1996-03/2017) for studies which generated synthetic CTs (sCT)s for MRI-only radiotherapy. 61 articles met the inclusion criteria.This review showed that MRI-only RTP techniques could be grouped into three categories: i]bulk density override ii]atlas-based and iii]voxel-based techniques, which all produce an sCT scan from MR image(s).Bulk density override techniques either used a single homogeneous or multiple tissue override. The former produced large dosimetric errors (>2%) in some cases and the latter frequently required manual bone contouring. Atlas-based techniques used both single and multiple atlases and included methods incorporating pattern recognition techniques. Clinically acceptable sCTs were reported, but atypical anatomy led to erroneous results in some cases. Voxel-based techniques included methods using routine and specialised MRI sequences, namely ultra-short echo time imaging. High quality sCTs were produced, however use of multiple sequences led to long scanning times increasing the chances of patient movement. Using non-routine sequences would currently be problematic in most radiotherapy centres.Atlas-based and voxel-based techniques were found to be the most clinically useful methods, with some studies reporting dosimetric differences of <1% between planning on the sCT and CT and <1mm deviations when using sCTs for positional verification.



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IGRT strategies for pelvic lymph node irradiation in high-risk prostate cancer: motion and margins

Publication date: Available online 8 September 2017
Source:International Journal of Radiation Oncology*Biology*Physics
Author(s): Lucy Kershaw, Laila van Zadelhoff, Wilma Heemsbergen, Floris Pos, Marcel van Herk
PurposeFor optimal irradiation of pelvic lymph nodes (LN) in high-risk prostate cancer, definition of margins to determine the planning target volume(s) is essential. Detailed quantification of the relative motion of the LN, seminal vesicles (SV) and prostate is currently lacking. This work aimed to quantify these motions and define margins for image-guided radiotherapy based on bony anatomy or prostate correction strategies for a 3 or 6 degrees-of-freedom couch.Material and MethodsNineteen patients had a planning CT followed by a mean of 11 repeated CTs during radiotherapy. The prostate, SV, external and internal iliac LN regions on the left and right were outlined on each CT. Systematic and random uncertainties were determined along with correlations between the motion of these regions. CTV-PTV margins required to take only motion into account were calculated for each guidance method.ResultsFor bone guidance, motion of prostate and LNs was largely uncorrelated. Margins to compensate for motion ((LR, SI, AP) in cm) based on a 3 degrees-of-freedom couch were; prostate: (0.2, 0.6, 0.8), SV: (0.4, 0.9, 1.0) and LN: (0.3, 0.4, 0.6). For prostate guidance, margins were calculated for correlated motion; prostate: (0, 0, 0), SV: (0.3, 0.5, 0.4) and LN: (0.3, 0.5, 0.9). For a 6 degrees-of-freedom couch, these margins were; prostate: (0.2, 0.6, 0.8), SV: (0.3, 0.9, 1.0) and LN: (0.3, 0.4, 0.3) for bone guidance. For prostate guidance, margins were; prostate: (0, 0, 0), SV: (0.2, 0.5, 0.4) and LN: (0.3, 0.6, 0.6)ConclusionsImage-guided radiotherapy based on bony anatomy requires larger prostate and SV margins, and guidance on prostate requires larger LN margins. Neither guidance strategy is optimal, and a combination of the two, or treatment adaption after a number of fractions might be preferable. Calculation of the total margin should also include delineation uncertainties.

Teaser

Definition of margins to determine the optimal image-guided radiotherapy (IGRT) strategy for pelvic lymph node irradiation is essential in high-risk prostate cancer. In this work, these margins were derived from systematic and random motions measured using repeated CT scans in 19 patients, based on matching to either bony anatomy or prostate for a 3 or 6 degrees-of-freedom (DOF) couch. When matching to bony anatomy, margins were smaller for lymph nodes than when matching to prostate, but larger for prostate and seminal vesicles. The prostate and seminal vesicle margins were unchanged when using a 3 vs 6 DOF couch, but lymph node margins were smaller in the anterior-posterior direction.


http://ift.tt/2gQCvI7

Subcutaneous implant-based breast reconstruction, a modern challenge in post mastectomy radiation planning

Publication date: Available online 8 September 2017
Source:Practical Radiation Oncology
Author(s): Melissa P. Mitchell, Jamie Wagner, James Butterworth
As survival rates for breast cancer continue to improve, there has been increasing interest in reducing toxicity of therapy. In the field of breast surgery, we have seen advancements in the surgical approach from total mastectomy to skin and nipple sparing mastectomy. Nodal surgery has also been significantly impacted by a "less is more" approach, sparing patients with healthy lymph nodes the side effect of axillary lymph node dissection by performing sentinel lymph node dissection to accurately assess the draining nodal basin. More recently, there have been increasing reports of techniques to improve options for reconstruction. A growing trend has been use of acellular dermal matrix (ADM). This has been reported to improve cosmesis and reduce the number of surgical procedures required to obtain desired aesthetic results. Additionally, there have been increasing reports of use of prepectoral ADM covered implants. As compared to traditional methods of using submuscular tissue expanders, devices placed in the prepectoral plane have been reported to reduce animation deformities and postoperative pain. There is also the benefit that muscular function will be preserved with a subcutaneous expander. Furthermore, there is a growing push for single stage procedures made possible through the use of ADM. This benefits the patient by subjecting them to less operations and benefits the health care system by decreasing health care costs, as compared to multiple stage surgeries.



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Factors Associated with Fatigue in Prostate Cancer (PC) Patients Undergoing External Beam Radiation Therapy (EBRT)

Publication date: Available online 8 September 2017
Source:Practical Radiation Oncology
Author(s): Hann-Hsiang Chao, Abigail Doucette, David M. Raizen, Neha Vapiwala
PurposeFatigue is a common adverse effect among cancer patients undergoing external beam radiation therapy (EBRT), yet the underlying disease- and treatment-related factors influencing its development are poorly understood. We hypothesized that clinical, demographic, and treatment-related factors differentially affect fatigue and aimed to better characterize variables related to fatigue development in prostate cancer (PC) patients during EBRT.MethodsWe identified a 681 patient cohort with non-metastatic PC undergoing a 6–9week EBRT course. Patient fatigue scores (range 0–3) were prospectively recorded by providers during treatment visits using standardized criteria. Clinical and demographic factors including age, race, EBRT details, disease staging, smoking status, comorbidities, urinary symptoms, employment status, weight, and concurrent medication use were assessed for their relationship to fatigue levels. Significant differences in fatigue severity by each variable at the beginning and end of EBRT were assessed by non-parametric-means testing, and differences in the level of fatigue increase over the treatment course were assessed using an ordered logistic regression model.ResultsSignificant increases in reported fatigue severity were seen in patients with: age<60years (p=0.006), depressive symptoms (p<0.001) and use of androgen deprivation therapy prior to radiation start (p=0.04). In addition, the prescription of antiemetics prior to radiation start was associated with reduced fatigue severity (p=0.03).ConclusionsWe identify factors associated with increased (young age, depressive symptoms, androgen deprivation therapy) and decreased (antiemetic prescription) fatigue in a large cohort of PC patients receiving EBRT. Continued investigation is needed to further elucidate clinical drivers and biological underpinnings of increased fatigue to guide potential interventions.



http://ift.tt/2vMBUxe

HPV related Nasopharyngeal and Cervical Cancer in a Married Couple in North America

Publication date: Available online 8 September 2017
Source:Practical Radiation Oncology
Author(s): Daniel B. Vanderbilt, Quoc-Anh Ho, Uma Goyal, Robert C. Bell, Robert R. Klein, Sun K. Yi




http://ift.tt/2vMgBw4

Plasma-rich plasma, the ultimate secret for youthful skin elixir and hair growth triggering

Summary

The clinical application of platelet-rich plasma (PRP) is based on the increase in the concentration of growth factors that are released from alpha-granule of the concentrated platelets and in the secretion of proteins which are able to capitalize on the healing process at the cellular level. It has been invented to restore the natural beauty by starting the natural rejuvenation process of the skin and aiming to make it function as a younger one and to keep the skin youthful and maintain it. Besides that, it is also emerged to include hairs as a new injectable procedure to enable stimulating hair growth locally and topically; preventing its fall; improving hair shaft, hair stem, and its caliber; increasing its shine, vitality, and pliability; and declining hair splitting and breakage. Thus, youth is in your blood as it has a magical power imposed in the platelet factors. There is, however, no standardization of the techniques besides insufficient description of the adopted procedures. Not long, autologous platelet-rich plasma (PRP) has surfaced strongly in diverse medical specialties including plastic, wound healing and diabetic ulcers, orthopedic, trauma, ocular surgery, dry eye for eyelid injection, urology for urinary incontinence, sexual wellness, cutaneous surgery, sport medicine, dentistry and dermatology, and aesthetic applications. PRP proved to promote wound healing and aid in facelift, volumetric skin, skin rejuvenation, regeneration, and reconstruction; improve wrinkling; stimulate hair growth; increase hair follicle viability and its survival rate; prevent apoptosis; increase and prolong the anagen hair growth stage; and delay the progression to catagen hair cycle stage with increased density in hair loss and hair transplantation. The aims of this extensive review were to cover all PRP application aspects that are carried out in aesthetic dermatology and to assess the literature on platelet-rich plasma outcomes on main aesthetic practices of general dermatology. A literature review was conducted by searching through PubMed, Biomedical Library database, Google Scholar, and Research Gate for the terms PRP, platelet-rich plasma, platelet-rich fibrin matrix, platelet preparations, platelet application therapy, platelet growth factors, platelet facial, platelet facial rejuvenation, platelet hairs, and platelet wound healing, from inception till 2017, and they were combined using Boolean operators. All those retrieved articles in English language were looked at and explored thoroughly.

http://ift.tt/2wPy9Kt

Seasonally-induced alterations of some facial signs in Caucasian women. Impact of a daily application of a photo-protective product

Abstract

Objectives

These were two-fold: i) to record through standardized pictures, the possible changes in 14 facial signs induced, in a 6-month period, by the periodical shift from winter to summer in a group of 42 Caucasian women residing in Paris and ii) to appraise the preventive effects of a strong photo-protective product, daily applied to their face by an additional group (N=40) of women of same age-range and presenting same severities of facial signs in winter.

Methods

Facial signs (structural and pigmentation-related) were graded in blind by a panel of 12 experts from photographs taken under standard conditions. Grading was performed under specific scales as previously published. A global and focused analysis of the skin colour or dark spots, when present, was carried out through spectro-radiometry under diffuse and standardized visible light, using the L*, a*, b* referential system.

Results

The unprotected group showed significant changes in summer as compared to winter on 10 facial signs (2/3 of the studied signs) that presented an increased severity, of variable respective amplitude. 5 signs among the 10 were particularly and significantly affected by the seasonal transition, of an amplitude above the precision of the grading scale. Three of these 5 signs concerned structural elements (wrinkles), the two others being related to vascular disorders (redness). These season-induced alterations appear efficiently alleviated in the photo-protected group. The colour of the facial skin then appears more homogeneous, less red, less dull, all criteria being quantified by the L*, a*, b* referential system. The comparison with a previous work carried out on Chinese women, through a similar protocol, shows that the photo-protective product brings, in Caucasian women, a more important effect upon structural and vascular features than upon pigmentation disorders, inversely to the results previously observed in Chinese women.

Conclusion

The alterations in some facial signs occurring in a 6-month period between winter and summer are confirmed in Caucasian women, mostly related to structural (wrinkles) and vascular elements. Such changes appear alleviated or prevented by daily applications of a strong sun photo-protective product.

This article is protected by copyright. All rights reserved.

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Downregulation of FOXP3 inhibits cell proliferation and enhances chemosensitivity to cisplatin in human lung adenocarcinoma

Publication date: Available online 8 September 2017
Source:Pathology - Research and Practice
Author(s): Chun Li, Liwei Sun, Rui Jiang, Peng Wang, Haogang Xue, Yudong Zhan, Xiaodong Gai
Our study aimed to investigate the biological role of FOXP3 expression in human lung adenocarcinoma (LAD) tissues and evaluate its involvement in cell proliferation and chemosensitivity to cisplatin in LAD cells. Paraffin-embedded tissues from 50 LAD patients were collected to detect FOXP3 and Ki-67 expression using immunohistochemistry (IHC). Downregulation of FOXP3 in A549 cells was performed using siRNA transfection. Real-time PCR or western blot assay was performed to analyze FOXP3 expression in A549 cells. Cell proliferation and cisplatin cytotoxicity test were assessed by CCK-8 assay. The expression of FOXP3 was significantly associated with lymph node metastasis and TNM stage of LAD patients. The FOXP3 expression was positively correlated with Ki-67 labelling index(LI)in LAD tissues. The downregulated expression of FOXP3 by siRNA transfection significantly inhibited cell proliferation and enhanced chemosensitivity to cisplatin in A549 cells. The expression of FOXP3 was significantly upregulated following cisplatin treatment in A549 cells. Our study indicates that FOXP3 may potentially be a novel molecular target in combating drug resistance in the chemotherapy of LAD.



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Scholar : Ειδοποίηση Μελετητή - [ ΜΑΣΤΟ

Ειδοποίηση Μελετητή:[ ΜΑΣΤΟΕΙΔΙΤΙΣ ]

Early signs and symptoms of intracranial complications of otitis media in pediatric and adult patients: A different presentation?

NA Van der Poel, E van Spronsen, DAD de Loos… - International Journal of …, 2017

... Search items included: acute otitis media, acute mastoiditis, chronic otitis media, otogenic
complications, intracranial complications, sinus thrombosis. ... Many publications are available on
the indications for imaging in patients with acute mastoiditis. Psarommatis et al. ...

[PDF] Otogenic lateral sinus Thrombosis: a rare complication of chronic Otitis media

E Ireo, P Gupta, G Dhanasekar - 2017

... LST may accompany substantial morbidity and mortality [1,3]. It is now an unusual intracranial
complication of otitis media, mastoiditis and cholesteatoma that accounts for 2-20% of intracranial
complications of middle ear infections [1,4]. The contributing ear diseases have ...

Cerebellar abscesses, infective endocarditis and bacteraemia due to a rare pathogen: Streptococcus constellatus.

CR García - BMJ case reports, 2017

... García Carretero R(1). Author information: (1)Hospital Universitario de Mostoles, Mostoles, Madrid,
Spain. Intracranial infections may result from contiguity, such as mastoiditis or acute otitis media,
or from haematogenous dissemination from an infectious source. ...

[HTML] Difference in the indices of adipose tissue and peripheral blood cells of individuals with overweight

L Gogiashvili, Z Tsagareli, E Nikobadze, E Melikadze… - Translational and Clinical …, 2017

TRANSLATIONAL AND CLINICAL MEDICINE - Georgian Medical Journal. ...

[HTML] Drug induced osteoporosis

N Khachidze, E Giorgadze - Translational and Clinical Medicine-Georgian Medical …, 2017

TRANSLATIONAL AND CLINICAL MEDICINE - Georgian Medical Journal. ...

[HTML] Oral complications of palliative patients with advanced cancer. 9 9 9

N Tebidze, M Jincharadze, V Margvelasvili - Translational and Clinical Medicine- …, 2017

TRANSLATIONAL AND CLINICAL MEDICINE - Georgian Medical Journal. ...

[PDF] Англомовна стоматологічна термінологія (семантичний аспект)

НМ Тхор - Записки з романо-германської філології, 2017

... teeth. Caries can be caused by osteomyelitis, which is a bacterial disease. A disease
that involves caries is mastoiditis, an inflammation of the mastoid process, in which
the bone gets eroded. Dental caries is one of many types. ...

Osteogenesis for postoperative temporal bone defects using human ear adipose‐derived stromal cells and tissue engineering: an animal model study

YJ Kim, SG Park, B Shin, J Kim, SW Kim, OS Choo… - Journal of Biomedical Materials …

... This article is protected by copyright. All rights reserved. Page 3. INTRODUCTION Mastoidectomy
is a surgical procedure performed to remove infected mastoid bone and air cells resulting from
ear infections such as otitis media and mastoiditis. This surgical ...

[PDF] Diseño de una ruta de atención primaria en salud del servicio faramacéutico para infección respiratoria aguda en primera infancia en la Red Sur de Bogotá

AV Medina Niño, A Ciucuamia, C Constanza - 2017

Page 1. Página 1 DISEÑO DE UNA RUTA DE ATENCIÓN PRIMARIA EN SALUD DEL SERVICIO
FARMACÉUTICO PARA INFECCIÓN RESPIRATORIA AGUDA EN PRIMERA INFANCIA EN LA
RED SUR DE BOGOTÁ Alex Vanessa Medina alemedina@udca.edu.co ...

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Scholar : Scholar Alert - [ intitle:laryngeal ]

Scholar Alert: [ intitle:laryngeal ]

Laryngeal Cytology in Cases with Equivocal Lesions of the Larynx

D Demirel, E Erkul, I Yilmaz, E Çekin, Z Kucukodaci… - Journal of the American …, 2017

Materials and Methods In this prospective ongoing study, 26 cases have been included until
the time of the abstract deadline. Laryngeal smears were procured using endocervical type
brushes and one or more punch biopsies were taken. In each case, alcohol fixed and air

Clinical characteristics of laryngeal versus nonlaryngeal amyloidosis

SF Rudy, CC Jeffery, EJ Damrose - The Laryngoscope, 2017

Methods The Stanford Translational Research Integrated Database Environment was
searched to identify patients with biopsy-confirmed laryngeal amyloidosis and patients with
amyloidosis without laryngeal involvement on endoscopy. Mann-Whitney U and χ 2 tests

[HTML] Ribonucleic acid interference knockdown of IL-6 enhances the efficacy of cisplatin in laryngeal cancer stem cells by down-regulating the IL-6/STAT3/HIF1 pathway

Q Fu, P Liu, X Sun, S Huang, F Han, L Zhang, Y Xu… - Cancer Cell International, 2017

Abstract Background Cisplatin has been used in the treatment of many cancers, including
laryngeal cancer; however, its efficacy can be reduced due to the development of drug
resistance. This study aimed to investigate whether interleukin-6 (IL-6) knockdown may

Kinematic evaluation of penetration and aspiration in laryngeal elevating and descending periods

H Kiyohara, K Adachi, Y Kikuchi, R Uchi… - The Laryngoscope, 2017

Objectives It is important to evaluate swallowing movements by dividing them into periods of
laryngeal closure and release. The purpose of this study was to evaluate penetration–
aspiration (PA) according to human pathophysiology and to identify the factors for predicting

[HTML] Comparison of the Supreme™ and ProSeal™ laryngeal mask airways in infants: a prospective randomised clinical study

S Oba, HS Turk, CT Isil, H Erdogan, P Sayin, AI Dokucu - BMC Anesthesiology, 2017

Abstract Background The Supreme™ and ProSeal™ laryngeal mask airways (LMAs) are
widely used in paediatric anaesthesia; however, LMA use in infants is limited because many
anaesthesiologists prefer to use tracheal intubation in infants. In this study, we compared the

Endoscopic optical imaging methods in the diagnostics of the laryngeal cancer

P Lukeš, E Lukešová, M Zábrodský, J Sýba… - Casopis lekaru ceskych, 2017

Endoscopic optical imaging methods for the detection of mucosal lesions in the ENT area
have been developed for better and earlier detection of these changes. They can be divided
into horizontal methods group-showing the surface of the mucous membrane

[PDF] Analysis of gene expression profiling variations induced by hsa‑miR‑145‑5p‑overexpression in laryngeal squamous cell carcinoma cell line Tu‑177

Y Ding, Y Wu, W Gao, C Zhang, Q Zhao, H Guo, X Qu… - Molecular Medicine Reports

Abstract The present study aimed to investigate the variations of the gene network and
biological functions induced by hsa‑miR‑145‑5p in the laryngeal squamous cell carcinoma
(LSCC) cell line Tu‑177. A hsa‑miR‑145‑5p‑overexpressed Tu‑177 cell model was

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