A straightforward method is presented to estimate peak skin doses (PSDs) delivered by computed tomography (CT) scanners. The measured PSD values are related to the well-known volume CT dose index (CTDI(vol)), displayed on the console of CT scanners. PSD measurement estimates were obtained, in four CT units, by placing radiochromic film on the surface of a CTDI head phantom. Six different X-ray ...

It would be useful to develop a tissue equivalent gel to improve the uniformity of the electromagnetic field in the human body, and for making a tissue equivalent dielectric human phantom. In this study, solid type, water based gelatin-honey gels were developed which have the electrical characteristics of skin tissue. It was demonstrated that a stable and homogeneous gel, with a relative dielec...

100 WORD ABSTRACT An RF receive-only phased-array coil for high-resolution in vivo imaging of human skin was developed. Simulations of signal-to-noise ratio (SNR) for various coil geometries—single loops and 2 and 3-element phased-arrays—were performed with respect to the special noise characteristics of small coils. The 2element phased-array coil was implemented. SNR measurements in a phantom ...

introduction: in patients with thyroid carcinoma, radiation absorbed doses of the thyroid and surrounding tissues is important to weigh risk and benefit considerations. in nuclear medicine, the accuracy of absorbed dose of internally distributed radionuclides is estimated by different methods such as mird and direct method using tld. the aim of this study is using tld and a phantom to determine...

Introduction:  Skin  sparing  is  one  of  the  most  desirable  characteristics  of  high  energy  photon  beams. However, the photons emerging from the target of linacs are contaminated by secondary  electrons  as  a  result  of  their  interactions  with  air,  collimators,  flattening  filter  and  any  other  objects in their path. This phenomenon tends to increase the skin dose received b...

Abstract The fabrication of multi-material medical phantoms with both patient-specificity and realistic mechanical properties is great importance for the development surgical planning training. In this work, a 3D printing system phantom manufacturing was developed. Rigid elastomeric materials are firstly combined in such application an accurate tactile feedback. designed multiple layers, where ...

Clinical results recently demonstrated improvement in lesion blanching using local vacuum to target small vessels in port wine stains (PWS) birthmarks laser therapy. The release of cryogen spurts under vacuum pressures may also offer many advantages to this therapeutic procedure due to different spray-surface interactions under vacuum conditions, which may lead to enhanced heat transfer. The ob...

PURPOSE The goal of this work was to evaluate measured vs. calculated surface dose as a function of PTV-to-skin proximity and calculation matrix oxel size, determine effects on plan quality, and provide parameters and levels of uncertainty for clinical use. METHODS A right-sided CTV with the lateral border 5mm from the surface was delineated on the CT data of a head and neck phantom. A 5mm PT...

A neonatal head phantom, comprising of an ellipsoidal geometry and including a circular aperture for simulating the fontanel was designed and fabricated, in order to allow an objective assessment of thermal rise in tissues during trans-cranial ultrasonic scanning of pre-term neonates. The precise position of a series of thermocouples was determined on the basis of finite-element analysis, which...

Experiments on patients with phantom limbs suggest that neural connections in the adult human brain are much more malleable than previously assumed. Three weeks after amputation of an arm, sensations from the ipsilateral face are referred to the phantom; this effect is caused by the sensory input from the face skin ‘invading’ and activating deafferented hand zones in the cortex and thalamus. Ma...