The present invention relates generally to a scanning system used to track a medical instrument for precise injection of a chemical into an injection location of a patient.
During a medical procedure, a chemical may need to be injected in a patient. The location of the injection must be precisely located to ensure that the chemical is injected at the proper location in the patient.
A scanning system includes a scanner having two x-ray sources. Prior to a medical procedure, the scanner takes an initial image of the patient. A known structure in the initial image is identified. Based on the initial image, an injection location of a chemical into the patient can be determined relative to the known structure.
During a medical procedure, a chemical is injected at the injection location through a tip of a medical instrument. The medical instrument includes at least two markers having a fixed and known relationship and orientation relative to each other and the tip of the medical instrument. The scanner operates in a fluoroscopy mode, and real-time images of the patient and the markers are shown on a display. The computer combines the images obtained from each of the x-ray sources to create one displayed image. Each x-ray source is automatically collimated to specifically direct the x-rays towards the injection location and the medical instrument, preventing additional x-ray exposure to the patient.
The relationship between the tip and the markers of the medical instrument is known, and the relationship between the known structure and the injection location is known. The computer monitors the movement of the tip as it is inserted into the patient and tracks the location of the tip relative to the injection location based on the detected relationship of the markers of the medical instrument and the known structure. When the computer determines that the tip is located at the injection location, the computer provides a signal to the surgeon. The surgeon then injects the chemical into the injection location using the medical instrument.
These and other features of the present invention will be best understood from the following specification and drawings.
The various features and advantages of the invention will become apparent to those skilled in the art from the following detailed description of the currently preferred embodiment. The drawings that accompany the detailed description can be briefly described as follows:
The gantry 12 includes a first arm 16 and a second arm 18. The first arm 16 houses two x-ray sources 20a and 20b that generate x-rays 28. In one example, the x-ray sources 20a and 20b are cone-beam x-ray sources. The second arm 18 houses a complementary flat-panel detector 22 spaced apart from the x-ray sources 20a and 20b. The x-rays 28 are directed toward the detector 22 which includes a converter (not shown) that converts the x-rays 28 from the x-ray sources 20a and 20b to visible light and an array of photodetectors behind the converter to create an image. Various configurations and types of x-ray sources 20a and 20b and detectors 22 can be utilized, and the invention is largely independent of the specific technology used for the scanner 10.
The scanner 10 further includes a computer 30 having a microprocessor or CPU 32, a storage 34 (memory, hard drive, optical, and/or magnetic, etc), a display 36, a mouse 38, a keyboard 40 and other hardware and software for performing the functions described herein. A plurality of images 58 taken by the detector 22 are sent to the computer 30. The images 58 are stored on the storage 34 of the computer 30 and can be displayed on the display 36 for viewing.
Prior to a medical procedure, the scanner 10 takes an initial image (CT or MRI) of the patient P that is stored by the computer 30. A known structure 56 in the initial image is identified. The known structure 56 can be a marker or markers positioned on the patient P (such as a metal BB) or a known specific structure in the patient's P anatomy. Based on the initial image, an injection location 60 for injection of a chemical (for example, a drug) can be determined. For example, the injection location 60 can be determined relative to the known structure 56. The injection location 60 is stored on the computer 30.
During the medical procedure, the chemical is injected in the patient P at the injection location 60. The chemical is injected through a tip 54 of a medical instrument 50. The medical instrument 50 includes at least two markers 52a and 52b. In one example, the markers 52a and 52b are metal BBs. In another example, the markers 52a and 52b are radio-opaque stripes. The markers 52a and 52b have a fixed and known relationship and orientation relative to each other and the tip 54 of the medical instrument 50.
During the medical procedure, the scanner 10 operates in a fluoroscopy mode, and real-time images 58 of the patient P and the markers 52a and 52b are shown on the display 36. The image associated with each of the x-ray sources 20a and 20b is stored by the computer 30, and the computer 30 combines the images obtained from each of the x-ray sources 20a and 20b to create one image 58 that is displayed on the display 36. That is, a portion of the images taken from each of the x-ray sources 20a and 20b overlap to create the displayed image 58.
X-rays 28 from both of the x-ray sources 20a and 20b are directed towards the injection location 60 and the medical instrument 50. Each x-ray source 20a and 20b is automatically collimated to specifically direct the x-rays towards the injection location 60 and the markers 52a and 52b of the medical instrument 50, preventing additional x-ray exposure to the patient P. The x-ray sources 20a and 20b are collimated such that the markers 52a and 52b are included in the image 58. If the computer 30 determines that one of the markers 52a and 52b are not visible in the image 58, the computer 30 then sends a signal to the x-ray source 20a and 20b to re-collimate the x-rays 28 until both the markers 52a and 52b are visible inside the images 58.
The relationship between the tip 54 and the markers 52a and 52b of the medical instrument 50 is known, and the relationship between the known structure 56 and the injection location 60 in the patient P is known. The computer 30 can detect the markers 52a and 52b and the known structure 56 in the images 58. Therefore, the computer 30 can monitor the movement of the tip 54 as it is inserted into the patient P and track the location of the tip 54 relative to the injection location 60 based on the information obtained in the images 58 and the relationship detected by the computer 30 between the markers 52a and 52b of the medical instrument 50 and the known structure 56.
For example, the computer 30 monitors the location of the markers 52a and 52a relative to the known structure 56 in the images 58 as the tip 54 moves. The location of the tip 54 relative to the injection location 60 can therefore be determined and monitored. A surgeon can also monitor the movement of the medical instrument 50 by observing movement of the markers 52a and 52b in the images 58 shown on the display 36 as the tip 54 is inserted into the patient P. The known structure 56 can also be visible in the images 58. When the computer determines that the tip 54 is located at the injection location 60 based on the known relationships, the computer 30 can provide a signal to the surgeon that the tip 54 is at the desired location. The surgeon then injects the chemical into the injection location 60 of the patient P using the medical instrument 50.
It is possible that both the markers 52a and 52b may not be visible in the image 58 at a given time based on the location and orientation of the medical instrument 50. That is, the medical instrument 50 could be oriented such that the markers 52a and 52b are aligned, preventing viewing and detection of both of the markers 52a and 52b in the image 58. If this occurs, the computer 30 generates an alarm to indicate that the orientation of the markers 52a and 52b relative to each other cannot be determined. The alarm can be visual or audio or any type of alarm. The medical instrument 50 can then be repositioned. Once the medical instrument 50 is oriented into a new position where the orientation of the markers 52a and 52b can be determined, the medical procedure can continue.
The foregoing description is only exemplary of the principles of the invention. Many modifications and variations are possible in light of the above teachings. It is, therefore, to be understood that within the scope of the appended claims, the invention may be practiced otherwise than using the example embodiments which have been specifically described. For that reason the following claims should be studied to determine the true scope and content of this invention.
This patent application claims priority to U.S. Provisional Application No. 60/944,234 filed on Jun. 15, 2007.
Number | Date | Country | |
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60944234 | Jun 2007 | US |