Christian Seebauer, Presenter: Nothing to Disclose

Tobias Jung MD, Abstract Co-Author: Nothing to Disclose

Florian Wichlas, Abstract Co-Author: Nothing to Disclose

Jens Rump, Abstract Co-Author: Nothing to Disclose

Ioannis Papanikolaou MD, Abstract Co-Author: Nothing to Disclose

Jens Georg Pinkernelle MD, Abstract Co-Author: Nothing to Disclose

Ivo R. van der Voort, Abstract Co-Author: Nothing to Disclose

Rene Schilling, Abstract Co-Author: Nothing to Disclose

Sascha Santosh Chopra MD, Abstract Co-Author: Nothing to Disclose

Ulf Teichgräber, Abstract Co-Author: Nothing to Disclose

Hermann Josef Bail MD, PhD, Abstract Co-Author: Nothing to Disclose

et al, Abstract Co-Author: Nothing to Disclose

Retrograde drilling techniques are clinically established. However, the poor visualization under X-ray control can lead to damage of the bone and cartilage. MRI is ideally suited for the evaluation of the osteocartilaginous components of talus lesions. The purpose of the study is the development of a MR-compatible drilling guide for the minimal-invasive treatment of OD under direct real-time MR-control in an open high field MRI device.

Artificial osteochondral defects were simulated in human cadaveric specimens. For drilling we used a custom-made MR-compatible c-shaped drilling device. For visualization, it was marked with liquid filled tubule on its opposite ends. All tests were performed on a 1.0T open MRI PANORAMA (Philips Medical Systems, Best, NL). The first step was to orientate the image plane in order to achieve the desired direction for the drilling. Under near real-time TSE image acquisition the drilling device was aligned to the selected plane using the filled markers as a reference. The two markers of the drilling guide were positioned in the direction of the osteochondral lesion of the talus. Multiple drillings were performed under interactive PDW TSE (TR:400 TE:8; 3.2s), T1W TSE (TR:100 TE:20; 3.5s) and T2W TSE (TR:1600 TE:90; 1.6s) control by a MR-compatible drilling machine (Invivo, Schwerin, Germany) with a 3.4mm titanium spiral drill. Histological specimens were made and the distance of the drilling canal and the artificial OD lesion were measured.

The drilling guide alignment was easy to handle. Histological specimens showed that the artificial lesion was hit without perforating the overlying cartilage. Due to the use of a low artifact titanium spiral drill and spin echo sequences metal-related susceptibility artifacts were minimal and allowed an exact assessment of anatomical structures and a safe drilling. Interactive T1W TSE, T2W TSE as well as PDW TSE were optimally eligible for near real-time image acquisition and intervention.

MRI provides the best available information about the condition of the bone surrounding the lesion and the overlying cartilage. MR-navigated drilling in combination with a non-invasive and MR-compatible drilling guide provides a superior approach, compared to conventional methods.

The MR navigated retrograde drilling of OD enabled precise drilling into the lesion without damaging the normal cartilage.

Seebauer, C, Jung, T, Wichlas, F, Rump, J, Papanikolaou, I, Pinkernelle, J, van der Voort, I, Schilling, R, Chopra, S, Teichgräber, U, Bail, H, et al, , Advancements in Orthopedic Intervention: Retrograde Talus Drilling under High Field MRI Guidance: A Cadaveric Study.  Radiological Society of North America 2008 Scientific Assembly and Annual Meeting, February 18 - February 20, 2008 ,Chicago IL. http://archive.rsna.org/2008/6021856.html