fidoptSynthRAD2025, CBCT to CT, thorax and abdomen
Cone-beam CT of one patient's thorax or abdomen and the CT to synthesise from it, the CT brought onto the CBCT's grid by the challenge (SynthRAD2025, Task 2).
Read before comparing (6)
- Case. The challenge's pair as delivered, copied byte for byte from its training archive synthRAD2025_Task2_Train.zip: the CBCT, the CT the organisers registered rigidly onto its grid, and their body mask. The archive is given after registration on the challenge's site.
- Mask. The challenge's body mask: the synthetic image is scored inside it, as the challenge scores it.
- Alignment. What the organisers' registration left misaligned counts as error for every method: it decides how far a perfect synthesis can match the CT.
- Baseline. Inside the mask on the 30 test cases, at CT's range of 4095, a constant at the target's median scores an MAE of 230 (133 to 415) HU, a PSNR of 20.9 (17.7 to 23.8) dB and an SSIM of 0.24 (0.01 to 0.52). The CBCT scores 183 (92 to 335) HU, 23.9 (20.6 to 28.0) dB and 0.33 (-0.03 to 0.69), better than the constant on 21 of the 30.
- Overlap. Besides its four registration sets, only DoseRAD2026_MRCT_Syn, Task 1 MR of centre B, draws on SynthRAD2025.
- Two tasks. The provider's two tasks may hold one patient under two numbers, so each drawn CT was registered rigidly to every same-region CT of SynthRAD2025_MRCT and DoseRAD2026_MRCT_Syn: they correlate at most 0.40 inside the bodies, against 0.95 or more for one CT cropped and moved. A Task 1 and a Task 2 patient of one number are not one patient (21 pairs compared, at most 0.32).
No method has a result on every case of this dataset yet.
Case by case
Click a score to look at that result: the target image, and over it the method's synthetic image. Underlined scores have their image; for the others you see the case without the result.
About the data
- Test cases
- 30 test patients drawn with seed 2026 by region and centre (abdomen and thorax; A, B, C, E) in proportion, then 30 development patients, the last of the same seeded order. The pool is 494 of the 514 abdomen and thorax patients of SynthRAD2025 Task 2's training archive: SynthRAD2025_CBCTCT's 10 test and 10 development patients are held out (draw.held_out), whose CT, the target here, is that set's public fixed image.
- Truth
- target image as released the patient's CT as the challenge delivers it, registered to the CBCT by the organisers, in Hounsfield units
- Licence
- CC BY-NC 4.0 (centres A, B, C, E)
30 cases for tuning, never tested
AB_2ABE170, TH_2THA107, TH_2THB111, TH_2THE046, AB_2ABE135, TH_2THA136, TH_2THB025, TH_2THE100, AB_2ABA086, AB_2ABB091, AB_2ABC129, AB_2ABE174, TH_2THA075, TH_2THB040, TH_2THC070, TH_2THE114, AB_2ABA047, AB_2ABB117, AB_2ABC097, AB_2ABE140, TH_2THA034, TH_2THB010, TH_2THC076, TH_2THE080, AB_2ABA071, AB_2ABB040, AB_2ABC118, AB_2ABE208, TH_2THA047, TH_2THB068