A paper published in the journal of Computerized Medical Imaging and Graphics (CMIG) reports the integration of C-arm cone-beam CT with a low-cost ultrasound imaging probe for needle interventions such as biopsy, tumor ablation, and pain management. The research reports a rigorous characterization of imaging performance for the ultrasound probe (Interson Vascular Access probe), including spatial resolution and contrast-to-noise ratio measured as a function of frequency and depth of field. The work also integrates the ultrasound probe via the PLUS Library for ultrasound-guided interventions, using a 3D-printed geometric calibration phantom and Polaris Vicra tracking system. The accuracy of image registration between ultrasound and cone-beam CT was ~2-3 mm at the needle tip, with anticipated improvement to be gained through enhancement of ultasound image quality. The work also demonstrates the potential for multi-modality (ultrasound-CBCT) deformable image registration using normalized mutual information (NMI), cross-correlation (NCC), or modality-insensitive neighborhood descriptors (MIND) similarity metrics. The research was supported by NIH, industry partnership with Siemens Healthcare, and a collaborative PhD student exchange program with the University Hospital Gregorio Marañón and University Carlos III de Madrid, first-authored by Dr. Eugenio Marinetto as part of his doctoral dissertation on advanced image-guided interventions.