Flowchart of concept of eye-tracking and beam-gating system for the treatment of ocular tumors.
Photograph of eye snout and part of eye beam delivery system at Korea National Cancer Center.
Three calibration modes defining actual image (mm/pixel). (a) Point-detection mode for automatic detection of patterns in “+” shape and image definition (mm/pixel). (b) Edge-detection mode for definition of image (mm/pixel) with reference to iris diameter previously measured at outpatient clinic. (c) Line-measurement mode for direct, ruler measurement of image (mm/pixel) with reference to known length of object. (d) Line-measurement mode for use in clinical setting.
(a) Process for establishing ROI of reference image and for capturing image. (b) Calibration and establishment of reference image. This process confirms a reference image and its origin. If the ROI establishment of a reference image or calibration fails, a retrial is possible.
Process of eye tracking and beam gating in calibration modes. (a) Eye position of patient is well maintained. (b) Beam is turned off when eye deviates beyond treatment tolerance value. (c) ROI of reference image can be displayed as rectangular shape.
Dosimetric results of dose distribution. (Solid line) Proton dose distribution when beam gating is not applied to nonmotion phantom. (Dashed line) Proton dose distribution when beam gating is not applied to motion phantom. (Dotted line) Proton dose distribution when beam gating with 0.5-mm treatment tolerance is applied to motion phantom.
Real-time X- and Y-axes total movement data for second treatment of third patient listed in Table IV.
Patient treated with system. In the case of this patient, the ROI of the reference was difficult to establish using the whole iris or pupil; thus, it was established using the margin of the iris corner. (a) Position of eye is maintained within treatment tolerance value. (b) Proton beams are blocked because eye position has deviated beyond treatment tolerance value.
Comparisons of the image (mm/pixel) between the three calibration modes.
Comparisons of accuracy rates of a motion phantom measured by using the three calibration modes.
Accuracy rates of our beam gating system by using films.
The result of patient data for eye movement during the treatment.
Article metrics loading...
Full text loading...