An X-ray CT apparatus is provided with an X-ray tube current modulation pattern calculation means that calculates an X-ray tube current modulation pattern based on a 3-dimensional model of an object calculated based on a scanogram image of the object, start-up shape acquisition means that acquires a start-up shape of CT values of a predetermined region of the object or CT value time differences after injecting contrast agent into the object, time contrast curve prediction means that predicts a time contrast curve indicative of a time sequential change of contrast in a diagnostic portion of the object at each slice position at a scan time based on the acquired start-up shape of the CT values or CT value time differences, object 3-dimensional model modification means that modifies a 3-dimensional model of the object based on the predicted time contrast curve, and X-ray tube electric current modulation pattern modification means that modifies the X-ray tube electric current modulation pattern based on the modified 3-dimensional model of the object.

X-ray CT apparatus

Surgical methods and devices allow closed-chest surgery to be performed on a heart of a patient while the heart is beating. A region of the heart is stabilized by engaging a surface of the heart with a stabilizer without having to stop the heart. Motion of the target tissues is inhibited sufficiently to treat the target tissues with robotic surgical tools which move in response to inputs of a robotic system operator. A stabilizing surface of the stabilizer is coupled to a drive system to position the surface from outside the patient, preferably by actuators of the robotic servomechanism. Exemplary stabilizers includes a suture or other flexible tension member spanning between a pair of jointed bodies, allowing the member to occlude a coronary blood vessel and/or help stabilize the target region between the stabilizing surfaces.

Stabilizer for robotic beating-heart surgery

A surgical system or assembly for performing cardiac surgery includes a surgical instrument (82); a servo-mechanical system engaged to the surgical instrument for operating the surgical instrument; and an attachment assembly for removing at least one degree of movement from a moving surgical cardiac worksite. The surgical system or assembly also includes a motion tracking system (88); and a control computer (34) engaged to the attachment assembly, the motion tracking system and to the servo-mechanical system for controlling movement of the attachment assembly and for feeding gathered information to the servo-mechanical system for moving the surgical instrument.

Performing cardiac surgery without cardioplegia

A magnetic resonance imaging system includes a magnetic field applying section for applying a static field, gradient field pulses, and an RF field to an object to be examined, a signal detecting section, including a homogeneous coil and a plurality of surface coils arranged to surround a desired region of the object, for detecting magnetic resonance signals from the object through the homogeneous coil and the surface coils, and an image data processing section for obtaining an image of the desired region by synthesizing image data based on the magnetic resonance signals respectively detected by the surface coils upon weighting/adding processing. The system uses differential surface coils as the surface coils. A magnetic resonance signal is detected through the homogeneous coil within the same time interval in which magnetic resonance signals are detected through the surface coils. Weighting functions for weighting/adding processing of image data are determined on the basis of these magnetic resonance signals.

Magnetic resonance imaging system

Improved robotic surgical systems, devices, and methods include selectably associatable master/slave pairs, often having more manipulator arms than will be moved simultaneously by the two hands of a surgeon. Four manipulator arms can support an image capture device, a left hand tissue manipulation tool, a right hand tissue manipulation tool, and a fourth surgical instrument, particularly for stabilizing, retracting, tool change, or other functions benefiting from intermittent movement. The four or more arms may sequentially be controlled by left and right master input control devices. The fourth arm may be used to support another image capture device, and control of some or all of the arms may be transferred back-and-forth between the operator and an assistant. Two or more robotic systems each having master controls and slave manipulators may be coupled to enable cooperative surgery between two or more operators.

Cooperative minimally invasive telesurgical system

Computed tomographic (CT) cardiac imaging in vivo has been hampered by motion of the heart during its cardiac cycle A technique of post data-acquisition correlation of the angular projection data using the electrocardiogram as a reference signal is described This method produced seven "stop action" images of the heart and resulted in delineating morphological detail not recognizable on the conventional CT scan

Stop-action cardiac computed tomography.

System and method are set forth enabling reconstruction of images of desired "frozen action" cross-sections of the heart or of other bodily organs or similar objects undergoing cyclic displacements. Utilizing a computed tomography scanning apparatus data is acquired during one or more full rotational cycles and suitably stored. The said data corresponding to various angular projections can then be correlated with the desired portion of the object's cyclical motion by means of a reference signal associated with the motion, such as that derived through an electrocardiogram--where a heart is the object of interest. Data taking can also be limited to only the times when the desired portion of the cyclical motion is occurring. A sequential presentation of a plurality of said frozen action cross-sections provides a motion picture of the moving object.

Method and system for cardiac computed tomography

CT images of the heart are significantly degraded by the effects of motion during the scanning interval. The use of electrocardiographic (ECG) gating to provide "stop-action" cardiac images remains limited by artifacts. A motion phantom has been constructed to allow systematic study of the artifact structure of ECG-gated images and to isolate the origins of these artifacts. "Stop-action" reconstructed images are presented demonstrating two classes of artifacts: (a) pinwheel artifacts that appear at the edges of high-contrast moving objects; and (b) linear streaks occurring in relation to missing views when an incomplete angular set of projections is used for image reconstruction with the convolution back-projection algorithm. These results underscore the use of the motion phantom for the analysis of image artifacts and stress the need for new CT reconstruction algorithms which are optmized for "stop-action" scanning.

Charles C. Morehouse

Papers

Stop-action cardiac computed tomography.

Method and system for cardiac computed tomography

Gated cardiac computed tomography with a motion phantom.

Cardiac ct in vivo