PEDRAIL TABLE FOR COMPUTER TOMOGRAPHY

PEDRAIL TABLE FOR COMPUTER TOMOGRAPHY

FIELD OF INVENTION

The invention generally relates to patient handling in medical diagnostic systems such as, computed tomography (CT) and more particularly to a structural design of a table component of CT system with improved patient handling mechanism.

BACKGROUND OF THE INVENTION

In general medical diagnostic systems, handles a patient by positioning vertically on a table that comprises a table top. Various conventional CT systems use a cradle table. FIG.1 shows a CT cradle table with a patient.

                        FIG.1
Usually, the cradle table comprises a four-link-shank structure with one moveable cradle on such structure. However, the conventional cradle tables have several disadvantages such as, cantilever bends easily when table is moved in forward direction.

FIG.2 Shows bent cantilever of a CT cradle table.

Gantry

Tube

Detector

Body

Cradle

Table

Position 2

FIG.2

Consequently, the bending of cantilever brings variable bending on the stationary scan position (in patient in-out direction). Therefore such cradle sag brings imperfect 3D recon image.

FIG.3 shows imperfect 3D recon image.

FIG.3

Further, the cradle sag has potential effect for image fusion in PET (Positron Electron Tomography) / CT modality and so on. Furthermore, the movement of the cradle table in

forward direction will cause potential cradle vibration in the scan position and consequently contribute to light shaking artifact for the image.

FIG.4 shows streak artifact in the image.

FIG.4

Because of the effect of conventional cradle shape, the conventional CT cradle table produces streak artifact in the image, especially when the edge of the cradle and some patient's part (e.g., rib) have combined effect on the image. Additionally, in conventional CT cradle table systems, a partial X-ray energy is absorbed and scattered by the cradle. As a result, the efficiency of X-ray decreases.

FIG.5 shows increased dose at same kV, noise and scan time.

FIG.5

Further, the studies using the cradle table in X-ray systems shows, increase in the dose up to 20 to 30% (for e.g., 200mA to 265mA) at same kV, noise and scan time.

FIG.6 shows increased noise at the same dose.

FIG.6

Furthermore, the noise is increased up to 21% at the same dose (for e.g., at 200mA). As a result, dose wasting is unavoidable with the convention cradle table.

Hence there exists a need for developing a table design for the CT systems with improved patient handling mechanisms.

BRIEF DESCRIPTION OF THE INVENTION

The invention provides a structural design for the table component of CT systems with improved patient handling mechanisms. The structural design of the CT table described herein is a pedrail table that allows easy patient transfer by moving the patient to forth and/or back t...