Highly precise navigation at the lateral skull base by the combination of flat-panel volume CT and electromagnetic navigation

This study aimed to evaluate the feasibility and accuracy of electromagnetic navigation at the lateral skull base in combination with flat panel volume computed tomography (fpVCT) datasets. A mastoidectomy and a posterior tympanotomy were performed on 10 samples of fresh frozen temporal bones. For registration, four self-drilling titanium screws were applied as fiducial markers. Multi-slice computed tomography (MSCT; 600 µm), conventional flat panel volume computed tomography (fpVCT; 466 µm), micro-fpVCT (197 µm) and secondary reconstructed fpVCT (100 µM) scans were performed and data were loaded into the navigation system. The resulting fiducial registration error (FRE) was analysed, and control of the navigation accuracy was performed. The registration process was very quick and reliable with the screws as fiducials. Compared to using the MSCT data, the micro-fpVCT data led to significantly lower FRE values, whereas conventional fpVCT and secondary reconstructed fpVCT data had no advantage in terms of accuracy. For all imaging modalities, there was no relevant visual deviation when targeting defined anatomical points with a navigation probe. fpVCT data are very well suited for electromagnetic navigation at the lateral skull base. The use of titanium screws as fiducial markers turned out to be ideal for comparing different imaging methods. A further evaluation of this approach by a clinical trial is required.

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Transcanal Computed Tomography Views for Transcanal Endoscopic Lateral Skull Base Surgery: Pilot Cadaveric Study

Journal of Neurological Surgery Part B Skull Base ◽

10.1055/s-0039-3400219 ◽

2019 ◽

Author(s):

Rory J. Lubner ◽

Samuel R. Barber ◽

Renata M. Knoll ◽

Judith Kempfle ◽

Daniel J. Lee ◽

...

Keyword(s):

Computed Tomography ◽

Skull Base ◽

Skull Base Surgery ◽

Imaging Study ◽

Preoperative Imaging ◽

Slice Thickness ◽

Imaging Evaluation ◽

Mean Values ◽

Lateral Skull Base ◽

Temporal Bones

Abstract Objectives Transcanal endoscopic operative approaches provide for a minimally invasive surgical portal to the lateral skull base. Traditional preoperative imaging evaluation involves computed tomography (CT) acquisition in the axial and coronal planes that are not optimized for the transcanal surgical corridor. Herein, we describe a novel CT-based “transcanal view” for preoperative surgical planning and intraoperative navigation. Study Design Present study is a cadaveric imaging study. Methods Cadaveric temporal bones (n = 6) from three specimens underwent high-resolution CT (0.625 mm slice thickness). Using three-dimensional (3D) Slicer 4.8, reformatted “transcanal” views in the plane of the external auditory canal (EAC) were created. Axial and coronal reformats were used to compare and measure distances between anatomic structures in the plane of the EAC. Results The degree of oblique tilt for transcanal CT reformats was 6.67 ± 1.78 degrees to align the EAC in axial and coronal planes. Anticipated critical landmarks were identified easily using the transcanal view. Mean values were 8.68 ± 0.38 mm for annulus diameter, 9.5 ± 0.93 mm for isthmus diameter, 10.27 ± 0.73 mm for distance between annulus and isthmus, 2.95 ± 0.13 mm for distance between annulus and stapes capitulum, 5.12 ± 0.35 mm for distance between annulus and mastoid facial nerve, and 19.54 ± 1.22 mm for EAC length. Conclusions This study is the first to illustrate a novel “transcanal” CT sequence intended for endoscopic lateral skull base surgery. Future studies may address how incorporation of a transcanal CT reformat may influence surgical decision making.

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Automatic Registration for Navigation at the Anterior and Lateral Skull Base

Annals of Otology Rhinology & Laryngology ◽

10.1177/0003489419849086 ◽

2019 ◽

Vol 128 (10) ◽

pp. 894-902 ◽

Cited By ~ 2

Author(s):

Julia Kristin ◽

Manuel Burggraf ◽

Dirk Mucha ◽

Christoph Malolepszy ◽

Silvan Anderssohn ◽

...

Keyword(s):

Skull Base ◽

Navigation System ◽

Automatic Registration ◽

Total N ◽

Electromagnetic Navigation ◽

Registration Error ◽

Target Registration Error ◽

Lateral Skull Base ◽

Significant Difference ◽

Electromagnetic Navigation System

Objective: Navigation systems create a connection between imaging data and intraoperative situs, allowing the surgeon to consistently determine the location of instruments and patient anatomy during the surgical procedure. The best results regarding the target registration error (measurement uncertainty) are normally demonstrated using fiducials. This study aimed at investigating a new registration strategy for an electromagnetic navigation device. Methods: For evaluation of an electromagnetic navigation system and comparison of registration with screw markers and automatic registration, we are calculating the target registration error in the region of the paranasal sinuses/anterior and lateral skull base with the use of an electromagnetic navigation system and intraoperative digital volume tomography (cone-beam computed tomography). We carried out 10 registrations on a head model (total n = 150 measurements) and 10 registrations on 4 temporal bone specimens (total n = 160 measurements). Results: All in all, the automatic registration was easy to perform. For the models that were used, a significant difference between an automatic registration and the registration on fiducials was evident for just a limited number of screws. Furthermore, the observed differences varied in terms of the preferential registration procedure. Conclusion: The automatic registration strategy seems to be an alternative to the established methods in artificial and cadaver models of intraoperative scenarios. Using intraoperative imaging, there is an option to resort to this kind of registration as needed.

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Application of Flat-Panel Volume Computed Tomography to Evaluate Cerebral Hemorrhage After Mechanical Thrombectomy of Acute Embolic Stroke of the Anterior Circulation

Journal of Computer Assisted Tomography ◽

10.1097/rct.0000000000001203 ◽

2021 ◽

Vol Publish Ahead of Print ◽

Author(s):

Ho-Hsian Yen ◽

Chun Chien ◽

I-Hui Lee ◽

Shih-Pin Chen ◽

Chao-Bao Luo ◽

...

Keyword(s):

Computed Tomography ◽

Cerebral Hemorrhage ◽

Mechanical Thrombectomy ◽

Embolic Stroke ◽

Flat Panel ◽

Anterior Circulation ◽

Volume Computed Tomography

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Reproducibility of trabecular structure analysis using flat-panel volume computed tomography

Skeletal Radiology ◽

10.1007/s00256-009-0707-9 ◽

2009 ◽

Vol 38 (10) ◽

pp. 1003-1008 ◽

Cited By ~ 14

Author(s):

Arnold C. Cheung ◽

Miriam A. Bredella ◽

Ma’moun Al Khalaf ◽

Michael Grasruck ◽

Christianne Leidecker ◽

...

Keyword(s):

Computed Tomography ◽

Structure Analysis ◽

Trabecular Structure ◽

Flat Panel ◽

Volume Computed Tomography

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Semi-Automatic Classification of Skeletal Morphology in Genetically Altered Mice Using Flat-Panel Volume Computed Tomography

PLoS Genetics ◽

10.1371/journal.pgen.0030118 ◽

2007 ◽

Vol 3 (7) ◽

pp. e118 ◽

Cited By ~ 16

Author(s):

Christian Dullin ◽

Jeannine Missbach-Guentner ◽

Wolfgang F Vogel ◽

Eckhardt Grabbe ◽

Frauke Alves

Keyword(s):

Computed Tomography ◽

Automatic Classification ◽

Flat Panel ◽

Skeletal Morphology ◽

Volume Computed Tomography

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TH-D-L100J-04: Dose and Image Quality of Flat-Panel Detector Volume Computed Tomography for Sinus Imaging

Medical Physics ◽

10.1118/1.2761694 ◽

2007 ◽

Vol 34 (6Part23) ◽

pp. 2634-2634 ◽

Cited By ~ 3

Author(s):

J Alspaugh ◽

E Christodoulou ◽

M Goodsitt ◽

J Stayman

Keyword(s):

Computed Tomography ◽

Image Quality ◽

Flat Panel ◽

Flat Panel Detector ◽

Volume Computed Tomography ◽

Detector Volume

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Imaging of Electrode Position after Cochlear Implantation with Flat Panel CT

ISRN Otolaryngology ◽

10.5402/2012/728205 ◽

2012 ◽

Vol 2012 ◽

pp. 1-5 ◽

Cited By ~ 8

Author(s):

Diana Arweiler-Harbeck ◽

Christoph Mönninghoff ◽

Jens Greve ◽

Thomas Hoffmann ◽

Sophia Göricke ◽

...

Keyword(s):

Computed Tomography ◽

Ct Scan ◽

Cochlear Implantation ◽

Electrode Array ◽

Electrode Position ◽

Flat Panel ◽

Volume Computed Tomography ◽

Metal Artefacts ◽

Flat Panel Ct ◽

Electrode Insertion

Background. Postoperative imaging after cochlear implantation is usually performed by conventional cochlear view (X-ray) or by multislice computed tomography (MSCT). MSCT after cochlear implantation often provides multiple metal artefacts; thus, a more detailed view of the implant considering the given anatomy is desirable. A quite new method is flat panel volume computed tomography. The aim of the study was to evaluate the method’s clinical use. Material and Methods. After cochlear implantation with different implant types, flat panel CT scan (Philips Allura) was performed in 31 adult patients. Anatomical details, positioning, and resolution of the different electrode types (MedEL, Advanced Bionics, and Cochlear) were evaluated interdisciplinary (ENT/Neuroradiology). Results. In all 31 patients cochlear implant electrode array and topographical position could be distinguished exactly. Spatial resolution and the high degree of accuracy were superior to reported results of MSCT. Differentiation of cochlear scalae by identification of the osseous spiral lamina was possible in some cases. Scanning artefacts were low. Conclusion. Flat panel CT scan allows exact imaging independent of implant type. This is mandatory for detailed information on cochlear electrode position. It enables us to perform optimal auditory nerve stimulation and allows feed back on surgical quality concerning the method of electrode insertion.

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