A new low-cost method of virtual cardiac dissection of computed tomographic datasets

Abstract

Computed tomography has an established role in the evaluation of a variety of cardiac disorders, including congenital heart diseases. The current generation of high-speed scanners produces volumetric data at low doses of radiation. The interpretation of cardiac anatomy, however, is generally limited to multiplanar assessment of two-dimensional images. The volume rendering technique provides an excellent three-dimensional demonstration of external morphology but offers little information about the intracardiac anatomy. The alternative approach of virtual cardiac dissection, which is a modification of volume rendering, on the other hand, provides crucial insights regarding the intracardiac anatomy. At present, virtual cardiac dissection requires expensive software packages. These software packages are not available in all countries, thus limiting its use in routine clinical care. We present here the details of a newly developed technique that permits virtual cardiac dissection using a personal computer and open-source software. Our technique involves no additional cost and can be achieved in the comfort of the office or operating room of the cardiologist, radiologist, or cardiac surgeon. This enhanced three-dimensional visualization of intracardiac anatomy will surely improve the understanding of the morphological details of both normal and malformed hearts. In addition, by permitting assessment in projections with which modern-day cardiologists and cardiac surgeons are conversant, it is likely to improve clinical decision-making. We illustrate here its potential utility in the morphologic assessment of the atrial septum and its deficiencies, along with malformations of the ventricular outflow tracts, including common arterial trunk.

Virtual Dissection: Emerging as the Gold Standard of Analyzing Living Heart Anatomy

“…Recent advances in visualization have permitted much needed three-dimensional reconstruction of datasets obtained from computed tomography and magnetic resonance imaging. Although commonly performed using commercial software packages, three-dimensional reconstruction can also be achieved using free open-source software [ 4 , 5 , 6 , 7 , 8 ]. These software are being increasingly used in clinical practice for diagnosis as well as to guide transcatheter and surgical intervention [ 9 , 10 , 11 , 12 , 13 ].…”

“…There is no doubt three-dimensional printed models and the increasing use of augmented and virtual reality can be extremely useful for education, procedural simulation and planning [ 12 , 43 , 44 , 45 ]. However, in our experience, utilizing the endocast and virtual dissection images on a monitor is often the most optimal strategy in clinical practice to provide a detailed evaluation of three-dimensional cardiac anatomy to support transcatheter and surgical planning while balancing costs and time efficiency [ 4 , 11 , 12 , 16 , 50 , 51 ]. Three-dimensional images in this paper were reconstructed using commercially available software/workstation (Horos, Pixmeo, Geneva, Switzerland; Ziostation2; Ziosoft, Tokyo, Japan; 3D Builder, Microsoft, Redmond, WA, USA).…”

Printing of Three-Dimensional Heart Models—Is It Worth the Expense?

“…This is the option to create virtual models from the 3-dimensional datasets and to interrogate them using freely available open-source software, such as Horos, and to view them on a personal computer. 2 …”

“… 1 about the underuse of printed models, we would challenge their suggestion that the use of open-source software does not alleviate one of the most significant limitations, namely, the need for skilled personnel with expertise in “performing segmentation.” 1 Although this may be true when creating virtual models using segmentation software such as Materialize Mimics, no such “segmentation” is required for virtual dissection. 2 , 3 Instead, virtual dissection is no more than a modification of the commonly performed volume-rendering technique. It can be achieved relatively easily by simply altering the opacities of colour maps using the 16-bit Colour Look Up Table editor, which is embedded within the software.…”

“…It can be achieved relatively easily by simply altering the opacities of colour maps using the 16-bit Colour Look Up Table editor, which is embedded within the software. 2 Further, the ease of producing reconstructions in clinically relevant views makes virtual dissection an ideal technique to guide planning ahead of surgical or interventional procedures. The images thus produced provide all necessary morphological details.…”