SBIR-STTR Award

This project proposes to enhance the capabilities of InnerOptic's InVision System (IVS) for needle guidance during hepatic tumor ablation procedures via an innovative and inexpensive method to warp pre-operative CT data in "real time." Ablation has been demonstrated as a promising alternative to surgical resection to treat hepatic tumors, but needle placement difficulties have been reported due to poor visualization of the anatomy with currently-available technology. Conventional ultrasound guidance is intra-operative, but some tumors are only visible in computed tomography (CT); however, CT data of soft tissue becomes obsolete as soon as the tissue moves even a small amount (e.g., from breathing). We have already developed the IVS technology to address this problem: with it, the positions and orientations of the ablation needle and of the intra-operative ultrasound transducer used for needle guidance are continually monitored. A stereoscopic computer-generated real-time visualization displays dynamic avatars of needle and transducer as the physician advances the needle towards the target; in this way, the spatial relationship between needle and ultrasound slice is clear, and the surgeon can more easily target a feature in the ultrasound slice with the ablation needle. Here, we propose an improvement to this guidance system that will enhance a physician's spatial understanding even further. We introduce a novel and computationally-inexpensive means to warp pre-operative computed tomography (CT) data, and an updated guidance system that incorporates the real-time-deformed CT data in registration with the intra-operative ultrasound. The physician would then benefit from the complementary information provided by both the ultrasound and CT data, and could optimally plan and execute the ablation procedure. In this Phase I, we propose to develop the prototype by enhancing our existing IVS, and thus leveraging hardware and software that is already available to us. We will then verify the performance accuracy of the system, and proceed with both quantitative and qualitative testing by our surgeon consultants. We will pursue two rounds of testing: the first will provide an opportunity to optimize the ergonomic aspects of the device, and the second will yield both quantitative and qualitative performance data. The technology described here is by no means limited to ablation procedures. In the future, it could in the future be adapted to any procedure in which needles, ultrasound and pre-operative scans such as CT or MRI are employed.

Public Health Relevance:
We propose an advanced visualization system for ablation of hepatic tumors, which is a surgical procedure in which a needle-like device is inserted into the center of a cancerous lesion and is energized in a way so as to "burn" and effectively remove the timorous tissue. A promising alternative to surgical resection, this approach has several advantages over traditional resection, including reduced trauma and recovery time for the patient, but it requires significant skill with ultrasonography for guidance in the careful placement of the probe that is required for maximization of tumor destruction, and minimization of healthy tissue destruction. The system proposed here will allow even a novice surgeon to place the probe accurately and quickly, and can enable an expert surgeon to perform the procedure more quickly.

Public Health Relevance Statement:
Principal Investigator/Program Director (Last, First, Middle): Razzaque, Sharif Project Narrative We propose an advanced visualization system for ablation of hepatic tumors, which is a surgical procedure in which a needle-like device is inserted into the center of a cancerous lesion and is energized in a way so as to "burn" and effectively remove the timorous tissue. A promising alternative to surgical resection, this approach has several advantages over traditional resection, including reduced trauma and recovery time for the patient, but it requires significant skill with ultrasonography for guidance in the careful placement of the probe that is required for maximization of tumor destruction, and minimization of healthy tissue destruction. The system proposed here will allow even a novice surgeon to place the probe accurately and quickly, and can enable an expert surgeon to perform the procedure more quickly. PHS 398/2590 (Rev. 09/04) Continuation Format Page

Project Terms:
Ablation; Abscission; Address; Anatomic; Anatomical Sciences; Anatomy; Animals; Aspiration, Respiratory; Body Tissues; Bovine Species; Breathing; Burn injury; Burns; CAT Scan, X-Ray; CAT scan; CT X Ray; CT scan; Cancerous; Cattle; Cognitive; Complex; Computed Tomography; Computer Programs; Computer software; Computerized Axial Tomography (Computerized Tomography); Computerized Tomography, X-Ray; Consult; Data; Data Set; Dataset; Devices; Diagnosis, Ultrasound; EMI scan; Echography; Echotomography; Effectiveness; Electromagnetic, Microwave; Excision; Extirpation; Family suidae; Feedback; Figs; Figs - dietary; Future; Glass; Hepatic; Human Resources; Image; Imagery; Implant; Inhalation; Inhaling; Inspiration, Respiratory; Intervention; Intervention Strategies; Laboratories; Left; Lesion; Life; Liver; Liver neoplasms; Load-Bearing; Loadbearing; Location; MR Imaging; MR Tomography; MRI; Magnetic Resonance Imaging; Magnetic Resonance Imaging Scan; Magnetism; Manpower; Measurement; Measures; Medical Imaging; Medical Imaging, Magnetic Resonance / Nuclear Magnetic Resonance; Medical Imaging, Ultrasound; Methods; Methods and Techniques; Methods, Other; Microwaves; Modality; Monitor; Motion; Movement; NMR Imaging; NMR Tomography; Needles; Neoplasms, Hepatic; Nuclear Magnetic Resonance Imaging; Operating Rooms; Operation; Operative Procedures; Operative Surgical Procedures; Oranges; Outcome; Patients; Performance; Phase; Physicians; Pigs; Pilot Projects; Position; Positioning Attribute; Principal Investigator; Procedures; Process; Programs (PT); Programs [Publication Type]; Qualitative Evaluations; Removal; Reporting; Research; Research Design; Scanning; Science of Anatomy; Slice; Software; Solutions; Study Type; Suidae; Surgeon; Surgical; Surgical Interventions; Surgical Procedure; Surgical Removal; Swine; System; System, LOINC Axis 4; TXT; Techniques; Technology; Testing; Text; Time; Tissues; Tomodensitometry; Tomography, Xray Computed; Transducers; Trauma recovery; Ultrasonic Imaging; Ultrasonic Transducer; Ultrasonogram; Ultrasonography; Ultrasound Test; Ultrasound transducer; Ultrasound, Medical; Update; Visualization; Weight-Bearing; Weight-Bearing state; Weightbearing; X-Ray Computed Tomography; Zeugmatography; anatomy; base; body movement; body system, hepatic; bovid; bovine; catscan; computed axial tomography; computer generated; computer program/software; computerized axial tomography; computerized tomography; cone-beam computed tomography; cow; design; designing; diagnostic ultrasound; ergonomics; experience; falls; hepatic neoplasia; hepatic neoplasm; imaging; imaging modality; innovate; innovation; innovative; inspiration; instrument; interventional strategy; liver tumor; magnetic; meetings; member; microwave electromagnetic radiation; microwave radiation; novel; organ system, hepatic; personnel; pilot study; porcine; programs; prototype; public health relevance; resection; skills; soft tissue; software systems; sonogram; sonography; sound measurement; spatial relationship; stereoscopic; study design; suid; surgery; tumor; ultrasound; ultrasound imaging; ultrasound scanning

We propose to develop an operating-room-ready system for needle guidance in soft tissue, which fuses intra- operative ultrasound and pre-operative X-ray computed tomography (CT) data by combining two novel technologies: 1) a radically different way of visualizing and interacting with the fused ultrasound and CT images, which we call Spotlight"; and 2) an innovative algorithm that automatically and continuously performs ultrasound-to-CT registration. Conventional image guidance during surgery has several problems. For example, intra-operative ultrasound guidance gives real-time feedback about the patient's anatomy, but some tumors are only visible in CT, which offers a higher resolution (and a larger 3D volume). On the other hand, a CT scan of soft tissue becomes obsolete as soon as the organs move by even a small amount, for example, due to breathing. The two modalities are usually viewed on separate monitors, which amplifies another problem: the appearance of anatomical features is usually different in ultrasound and in CT, and there is no visual correspondence between them. Furthermore, the pre-operative annotations of the CT-indicating the locations of tumors or lesions-cannot be seen in the context of the ultrasound. In this proposal, we address these problems by developing a guidance system that: 1) registers and fuses pre- operative CT with intra-operative ultrasound; 2) dynamically volume-renders the CT scan and its pre-operative annotations in such a way as to highlight the most relevant portions of the dataset given the position of the ultrasound transducer and needle, while still indicating the remaining portions of the dataset for context; and 3) allows for intra-operative annotation to both modalities. To this end, we propose to refine and evaluate Spotlight iteratively, using phantoms and human patients. We also propose to develop a novel ultrasound-to- CT registration technique, to make it suitable for real-time operation during interventions, and to evaluate it, integrated with Spotlight, on human patients. For the evaluation, we will initially deploy the system in open surgical microwave ablation of liver tumors, but the technology is not limited to that specific intervention. In the future, it would be adapted to any procedure in which needles, ultrasound and pre-operative scans such as CT or MRI are employed. Our proposed system has potential to dramatically improve the utility of CT in the operating room, increasing the likelihood of an effective, efficient and complete intervention and improved patient outcome.

Public Health Relevance:
We propose to develop a system that registers and visualizes pre-operative CT and intra-operative ultrasound images during surgical interventions. This system provides to the surgeon a combination of the two modalities' benefits while negating each other's shortcomings, allowing him to more effectively and efficiently perform the intervention. The surgeon can also make intra-operative annotations to both modalities with our system, so that he can mark all tumors that he intends to treat. Patient benefits of such a system will include shorter operating time, reduced risk of injury, and increased probability of complete tumor removal, in a variety of interventions, such as ablation, biopsy, and drug delivery.