Evaluation of spatial precision and accuracy of cone-beam CT using an in vitro phantom model.

OBJECTIVE: High accuracy and precision are essential in stereotactic neurosurgery, as targeting errors can significantly affect clinical outcomes. Image registration is a vital step in stereotaxis, and understanding the error associated with different image registration methods is important to inform the choice of equipment and techniques in stereotactic neurosurgery. The authors aimed to quantify the test-retest reliability and stereotactic accuracy of cone-beam CT (CBCT) compared with the current clinical gold-standard technique (i.e., CT). METHODS: Two anthropomorphic phantom models with 40 independent unique steel spheres were developed to compare CBCT frame and stereotactic space registration with the clinical gold standard (CT). The cartesian coordinates of each sphere were compared between the imaging modalities for test-retest reliability and overall accuracy. RESULTS: Both imaging modalities showed similar levels of fiducial deviation from the expected geometry. The equivalence test demonstrated mean differences between CT and CBCT registration of -0.082 mm (90% CI -0.27 to 0.11), -0.045 mm (90% CI -0.43 to 0.34), and -0.041 mm (90% CI -0.064 to 0.018) for coordinates in the x-, y-, and z-axes, respectively. The mean euclidean distance difference between the two modalities was 0.28 mm (90% CI 0.27-0.29). CONCLUSIONS: Accuracy and precision were comparable between CBCT and CT image registrations. These findings suggest that CBCT registration can be used as a clinically equivalent substitute to gold-standard CT acquisition.

The economic and clinical benefits of portable head/neck CT imaging in the intensive care unit.

* There is a 13% morbidity associated with transporting critically-ill patients outside of the ICU. The incidence of adverse events during transport specifically for CT imaging is as high as 71%. The objective of this study was to assess the feasibility and cost-effectiveness of a portable CT scanner designated to perform bedside imaging in the ICU. * A fully mobile 8-slice head/neck CT scanner was evaluated for efficiency and personnel allocation. The return-on-investment for the purchase of the portable scanner was calculated. * Data demonstrates that the introduction of a portable CT scanner in the ICU is feasible and cost-effective. At the Cleveland Clinic in Mayfield Heights, Ohio, the portable scanner provided a full return-on-investment within the first 6.9 months of its operation, an internal rate of return of 169%, and a 5 year expected economic benefit of $2,619,290.

Non-invasive coronary angiography with multi-detector computed tomography: comparison to conventional X-ray angiography.

Selective coronary angiography introduced clinical coronary imaging in the late 1950s. The angiographic identification of high-grade coronary lesions in patients with acute and chronic symptomatic coronary artery disease (CAD) led to the development of surgical and percutaneous coronary revascularization. However, the fact that CAD remains the major cause of death in North America and Europe demonstrates the need for novel, complementary diagnostic strategies. These are driven by the need to characterize both increasingly advanced disease stages but also early, asymptomatic disease development. Complex revascularization techniques for patients with advanced disease stages will initiate a growing demand for 3-dimensional coronary imaging and integration of imaging modalities with new mechanical therapeutic devices. An emerging focus is atherosclerosis imaging with the goal to identify subclinical disease stages as the basis for pharmacological intervention aimed at disease stabilization or reversal. Non-invasive coronary imaging with coronary multidetector computed tomographic angiography (MDCTA) allows both assessment of luminal stenosis and subclinical disease of the arterial wall. Its complementary role in the assessment of early and advanced stages of CAD is increasingly recognized.

Computed tomography assessment of thoracic aortic pathology.

Computed tomography technology has improved dramatically in the past decade and now constitutes the backbone of preoperative evaluation for aortic disease. Image acquisition is accomplished with multi-row detectors, and coupled with new reconstruction algorithms provide clinicians with high-resolution images that can be visualized in synch with the cardiac cycle, or as complex three-dimensional renditions of in vivo anatomy. Knowledge regarding the means of data acquisition, reconstruction algorithms, and modes of interpretation are critical for the optimal assessment of aortic disease. These issues are increasingly important as endovascular therapy becomes more commonplace for the treatment of thoracic aortic lesions.