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Table 1 Median and range of DSC, MSD and HD95 per OAR

From: Interobserver variability in organ at risk delineation in head and neck cancer

  DSC MSD (mm) HD95 (mm) Nr. of contours by RO using Brouwer et al. guidelines (max = 27) Nr. of contours by RO using no/other guidelines (max = 35)
Median Range Median Range Median Range
Min Max Min Max Min Max
Brainstem 0.88 0.61 0.92 1.5 1.1 4.0 4.0 2.3 15.0 24 (89%) 31 (89%)
Cochlea left 0.45 0.00 0.79 1.9 0.8 11.0 3.7 1.9 14.9 16 (59%) 9 (26%)
Cochlea right 0.38 0.00 0.83 2.1 0.9 10.5 4.1 1.5 14.4 16 (59%) 9 (26%)
Glottic area 0.45 0.17 0.87 2.8 0.9 8.4 9.4 1.8 18.5 13 (48%) 10 (29%)
Mandible 0.90 0.79 0.94 1.1 0.8 8.3 3.4 1.5 38.7 26 (96%) 29 (83%)
Oral cavity 0.77 0.45 0.91 4.6 1.8 11.6 14.5 4.3 30.1 19 (70%) 23 (66%)
Parotid left 0.82 0.62 0.88 1.9 1.2 4.2 4.9 3.1 16.5 27 (100%) 35 (100%)
Parotid right 0.83 0.51 0.90 2.0 1.4 4.9 5.1 3.2 19.2 26 (96%) 35 (100%)
PCM-inferior 0.53 0.00 0.78 2.9 1.1 16.8 12.2 2.6 78.0 12 (44%) 6 (17%)
 Middle 0.53 0.29 0.82 3.8 0.9 13.4 12.1 2.0 36.0 12 (44%) 7 (20%)
 Superior 0.50 0.19 0.73 2.6 1.3 6.7 10.5 3.2 27.5 12 (44%) 7 (20%)
Spinal cord 0.78 0.56 0.90 2.2 0.8 10.4 12.1 1.7 72.1 17 (63%) 34 (97%)
SMG left 0.87 0.57 0.91 1.3 0.9 3.4 3.1 1.8 12.2 26 (96%) 24 (69%)
SMG right 0.87 0.72 0.92 1.2 0.9 2.5 3.1 1.9 10.1 27 (100%) 24 (69%)
Supragl. larynx 0.65 0.11 0.86 3.5 1.0 13.3 9.6 3.0 28.7 11 (41%) 9 (26%)
  1. Median and range were calculated over all delineations made by all radiation oncologists on all cases. The number of delineations varies for each OAR as shown in the 2 right columns. Radiation oncologists who use the guidelines from Brouwer et al. delineate the cochleas, glottic area, PCSM,s, SMG and supraglottic larynx more than other radiation oncologists. The spinal cord however was delineated less, because 2 RO delineated the spinal canal instead
  2. DSC Dice Similarity Coefficient, HD95 95% Hausdorff distance, mm millimetre, MSD mean surface distance, PCM pharyngeal constrictor muscles, RO radiation oncologist, SMG submandibular gland, Supragl supraglottic