Question

1-What is the differences between the 1st generation and 2nd generation CT scanners

2-What is the difference between the transmission geometry and reflectance geometry

3-Explain the working principles of respiratory gating and card

Answer 1

1-What are the differences between the 1st generation and 2nd generation CT scanners

"Generation" the request in which CT scanner configuration has been presented, and every ha a number related with it.

First generation

Second generation

Configuration: single X-beam source and single X-beam finder cell to gather every one of the information for a solitary cut y Source and locator, inflexibly coupled Shaft: Pencil pillar y made an interpretation of crosswise over patient to acquire set of parallel projection estimations at one edge Source/finder turn somewhat and a resulting set of estimations are gotten amid an interpretation past patient Process is rehashed once for every projection edge until 180 projections , over a 24 cm FOV Interpretation and revolution process, this geometry is alluded to as a decipher/turn scanner

Outline: numerous locators y B/C X-beam source discharges radiation over an extensive point, the proficiency of estimating projections was extraordinarily moved forward Source and cluster of identifiers are deciphered as in an original framework y yet since pillar estimated by every finder is at a somewhat unique point regarding object, every interpretation step produces numerous parallel beam projections Various projections got amid every traversal past the patient y this scanner is fundamentally more productive and quicker than first one This age :an interpret/turn scanner

2-What is the difference between the transmission geometry and reflectance geometry

I have perused from different sources that the intelligent geometry in X-beam powder diffraction (XRPD), gives higher determination than the transmission geometry. My analysis utilizes a parallel shaft delivered by a poly capillary collimating optic, with low disparity (3.5 mrad at Cu Ka), so I am overlooking uniqueness for straightforwardness. There are no accepting opening situated between the example and identifier.

In the transmission geometry (approaching bar is orthogonal to test), if the lighting bar measure is 50 microns, at that point 50 microns of the example is illuminated and the diffracted pillar size will be ~ 50 microns. In the intelligent geometry (lets expect a 3 degree episode edge), if the illuminating bar is 50 microns, at that point ~ 1 mm of the example is lighted and the diffracted pillars are additionally ~ 1mm. The measure of test lighted in the intelligent geometry can be figured as 'W/Sin(theta)', where W is the bar size and theta is the occurrence point. In this manner, in light of my estimations, the intelligent geometry improves determination than transmission geometry.

3-Explain the working principles of respiratory gating and card

C-RAD is glad to introduce the cutting edge respiratory gating arrangement in light of the progressed Sentinel™ and Catalyst™ optical surface following advances. Usefulness for review (4D CT) and planned gating is bolstered, requiring just a single Sentinel™ laser scanner framework in every CT room. So also, gated medications are upheld by introducing one Catalyst™ framework in every treatment room. (Correct usefulness is relying upon accessibility of the particular interfaces.) The C-RAD optical gating arrangement requires no fiducials or markers, and is intended to guarantee that similar focuses at first glance are naturally followed at each portion. The outline offers consistent help all through the whole CT recreation, treatment arranging, and conveyance periods of the radiation treatment process. Adjusted to isocenter in each vault, both the Sentinel™ and Catalyst™ work in the outright room arrange framework, cautioning the administrator to all remotely perceivable benchmark moves in a split second. The arrangement offers bolster for a few procedures, for example, profound motivation breath-hold, free breathing, instructed breathing and so forth. Moreover are there capacities included for quick recognition of unpredictable breathing and patient movement, guaranteeing most extreme wellbeing amid the basic treatment conveyance. The C-RAD gating arrangement depends on the standard of direct optical triangulation, yielding low latencies for enhanced exactness and wellbeing amid gated imaging and treatment conveyance. The patients are not presented to any extra measurements for following the respiratory movement. The consolidated Sentinel™/Catalyst™ framework offers the accompanying favorable circumstances contrasted with other accessible answers for respiratory gating:

•           No markers or other hardware to be put nearby the patient.

•           Tracking of both thoracic and stomach movement, performed persistently and in parallel which is essential to both set up and along these lines check the relationship between's outside (surrogate) and interior (target) movement.

•           Direct optical triangulation estimations, giving submillimeter precision at each distinguished point with low affectability to surrounding light.

The final product is an entire gating answer for CT and linac with discretionary abilities for tolerant se-up and situating, general intra-portion movement location and other propelled applications – without the need to introduce any extra equipment.

Accept the way things are:

Gated treatment conveyance depends on a gated arranging CT think about, which builds up the relationship between's the outside and inside movement. The CT study can be gated in either planned or review mode.

Tentatively gated CT consider amid planned gating of the CT, the patient's respiratory movement is checked and the CT will just obtain pictures when the respiratory flag is inside a foreordained gating window. Forthcoming mode is utilized when the proper breathing state is known previously (e.g. profound motivation breath hold method). This spares persistent dosage and streamlines treatment arranging in light of the fact that, as on account of non-gated medicines, just a 3D volumetric informational collection should be considered.

Reflectively gated CT consider (4D CT) if there should be an occurrence of review gating (otherwise known as 4D CT), the caught CT cuts will be arranged by their particular respiratory stage and the last informational collection will contain numerous volumetric pictures, obviously indicating how the patient's life systems is changing through the entire breathing cycle. The stages most fitting for treatment conveyance is then chosen. The significant CT volumes are amassed, either by the CT workstation programming or the treatment arranging framework, into a solitary 3D volume for consequent treatment arranging.

Gated treatment arranging and conveyance Based on the arranging CT examine (either reflectively or tentatively gated), treatment arranging is then performed. In the treatment room, the patient's respiratory movement is checked and the treatment pillar will be turned on just when the flag is inside the officially settled gating window. Notwithstanding being a piece of the C-RAD gating arrangement, the C-RAD Catalyst™ additionally incorporates numerous different functionalities: The movement identification usefulness of Catalyst™ screens the patient for conceivable developments without the utilization of any markers or fiducials and creates an alert or bar hold on the off chance that the patient moves outside of set points of confinement. Through cutting edge nonrigid enlistment calculations, the isocentric move is persistently processed. This gives expanded certainty while in the meantime limiting the danger of false alerts.

The propelled quiet set-up and situating usefulness of Catalyst™ offers a work process arranged instrument for the RT-office to build the precision in blend with higher proficiency in the frequently tedious patient set-up and situating strategy. Stance blunders are anticipated straightforwardly onto the patient as a persistently refreshed separation delineate, exceptional ergonomic advantages.

About Respiratory Gating:

Advances in radiation treatment amid the previous couple of decades has empowered conveyance of exceptionally conformal treatment designs through procedures, for example, IGRT, IMRT and IMAT. These advancements give the capability of curing more tumor patients with less reactions. In any case, even today most treatment designs are as yet in light of a solitary, static, 3D arranging CT dataset. Respiratory-initiated movement in this way stays one of the significant difficulties while treating focuses in the thoracic and stomach district. Respiratory gating offers an answer by synchronizing pillar conveyance to the patient's relaxing. The bar will be turned on just when the objective is in the right position as indicated by the treatment design. This empowers more measurement to be conveyed to the objective volume while saving encompassing solid tissue and ensuring organs in danger.