"Direct MPR": A Useful Tool for Oblique CT Fluoroscopy-Assisted Puncture.

Objective: Conventional multiplanar reconstruction (MPR) imaging can be used as a tool for planning oblique puncture procedures, but it takes a few minutes to reconstruct and is not appropriate for real-time CT fluoroscopy-assisted puncture. Recently, new MPR technology has been used that requires only 8 s and makes it possible to obtain a nearly real-time CT fluoroscopy-assisted oblique puncture. We refer to it as "direct MPR." This is the first clinical report of this technique.

Methods: Since February 2016, we have performed real-time, CT-guided oblique punctures with this new technology, "direct MPR," using an angio-CT system. We retrospectively reviewed all of our procedures with this new method between February 2016 and June 2016.

Results: We used this technique for 14 cases during the study period. Eight cases were radiofrequency ablation (RFA) for hepatocellular carcinoma (HCC), four were biopsies (lung and adrenal gland), and two were for percutaneous abscess drainage. Six of eight RFA cases were for HCC located immediately below the diaphragm. Both of the drainage cases were abscesses located immediately below the diaphragm. All procedures were successfully completed. The average length of the lesion in the RFA cases was 15.4 ± 3.2 mm. The average length of the lesions in all of the cases was 30.9 ± 31.9 mm. The average craniocaudal angle was 32.5° ± 14.0°.

Conclusions: Direct MPR makes CT-guided oblique puncture for inaccessible targets, especially those located immediately below diaphragm, easier and safer.

Level Of Evidence: Case series, Level IV.