Radiation Dose of the Lens in Trans-sphenoidal Pituitary Surgery: Pros and Cons of a Conventional Setup Using Fluoroscopic Guidance and CT-Based Neuronavigation
S. Ulmera,
E. Schulzd,
B. Moellerb,
U.R. Krausec,
A. Nabavic,
H.M. Mehdornc and
O. Jansena
a Section of Neuroradiology, Department of Neurosurgery, University Hospital of Schleswig-Holstein, Kiel, Germany
b Department of Neurology, University Hospital of Schleswig-Holstein, Kiel, Germany
c Department of Neurosurgery, University Hospital of Schleswig-Holstein, Kiel, Germany
d Department of Radiology and Nuclear Medicine, University Hospital of Schleswig-Holstein, Luebeck, Germany
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Fig 1. A, The anthromorphic Alderson-Rando head phantom consists of 1-inch-thick sections with predrilled holes. The arrowheads mark the locations of the TLDs (size relation demonstrated in the upper right corner, 6 mm long, 1 mm diameter) placed on the lenses of the phantom. B, Lateral localizer of the phantom on CT with the plotted image stack covering the maxilla to the frontal bone and reference section (as displayed in C) through the orbital cavity. C, Axial CCT image of the phantom through the orbital cavity with attached TLD on the topographic site of the lenses and adjacent to it on the temporal bone. The TLDs are well depicted. D, Magnification of the box in C. The TLDs (circle) are depicted on the scan on 2 consecutive sections.
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Fig 2. Radiation dose plotted against time course. There is a linear time-dependent increase of the radiation dose close to the primary beam (R2 = 99.27, P < .0001).
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Fig 3. Radiation dose plotted against time course with continuous fluoroscopy (squares) and CCT (crosses). Both lines cross after 14 minutes 20 seconds.
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