OCT

Optical Coherence Tomography

Standard reconstruction benchmark — forward model perfectly known, no calibration needed. Score = 0.5 × clip((PSNR−15)/30, 0, 1) + 0.5 × SSIM

# Method Score PSNR (dB) SSIM Source
🥇 ScoreOCT 0.869 37.95 0.973 ✓ Certified Wei et al., ECCV 2025
🥈 DiffusionOCT 0.860 37.52 0.970 ✓ Certified Zhang et al., NeurIPS 2024
🥉 SpeckleFormer 0.846 36.85 0.964 ✓ Certified Devalla et al., ECCV 2024
4 RetinalFormer 0.836 36.35 0.960 ✓ Certified Chen et al., ICCV 2024
5 OCT-ViT 0.831 36.12 0.958 ✓ Certified Tian et al., ICCV 2024
6 OCTA-Net 0.798 34.6 0.942 ✓ Certified Hybrid U-Net+Transformer, 2023
7 U-Net-OCT 0.782 33.85 0.935 ✓ Certified U-Net variant
8 Speckle-DenoiseNet 0.764 33.1 0.925 ✓ Certified Devalla et al., BOE 2019
9 NLM-OCT 0.688 30.2 0.870 ✓ Certified Non-local means variant
10 BM4D 0.663 29.3 0.850 ✓ Certified Maggioni et al., IEEE TIP 2013
11 TV-Denoising 0.632 28.5 0.815 ✓ Certified TV regularization
12 Speckle-Lee 0.609 27.85 0.790 ✓ Certified Lee, IEEE TGRS 1980
13 FFT-OCT 0.537 25.6 0.720 ✓ Certified Analytical baseline

Dataset: PWM Benchmark (13 algorithms)

Blind Reconstruction Challenge — forward model has unknown mismatch, must calibrate from data. Score = 0.4 × PSNR_norm + 0.4 × SSIM + 0.2 × (1 − ‖y − Ĥx̂‖/‖y‖)

# Method Overall Score Public
PSNR / SSIM
Dev
PSNR / SSIM
Hidden
PSNR / SSIM
Trust Source
🥇 SpeckleFormer + gradient 0.773
0.806
34.31 dB / 0.963
0.783
33.26 dB / 0.955
0.731
29.87 dB / 0.915
✓ Certified Devalla et al., ECCV 2024
🥈 RetinalFormer + gradient 0.771
0.824
34.92 dB / 0.967
0.765
31.56 dB / 0.938
0.723
30.02 dB / 0.917
✓ Certified Chen et al., ICCV 2024
🥉 OCT-ViT + gradient 0.770
0.819
34.39 dB / 0.964
0.768
31.66 dB / 0.939
0.723
30.29 dB / 0.921
✓ Certified Tian et al., ICCV 2024
4 ScoreOCT + gradient 0.769
0.843
36.51 dB / 0.976
0.759
30.92 dB / 0.930
0.705
29.4 dB / 0.907
✓ Certified Wei et al., ECCV 2025
5 DiffusionOCT + gradient 0.746
0.837
36.33 dB / 0.975
0.719
28.61 dB / 0.893
0.682
27.32 dB / 0.866
✓ Certified Zhang et al., NeurIPS 2024
6 OCTA-Net + gradient 0.672
0.777
32.09 dB / 0.944
0.645
25.08 dB / 0.805
0.593
22.87 dB / 0.726
✓ Certified Hybrid U-Net+Transformer, 2023
7 Speckle-DenoiseNet + gradient 0.662
0.752
30.11 dB / 0.918
0.637
25.37 dB / 0.814
0.596
23.87 dB / 0.764
✓ Certified Devalla et al., BOE 2019
8 Speckle-Lee + gradient 0.653
0.655
25.19 dB / 0.808
0.654
25.24 dB / 0.810
0.651
25.71 dB / 0.824
✓ Certified Lee, IEEE TGRS 1980
9 TV-Denoising + gradient 0.645
0.706
27.48 dB / 0.869
0.633
25.0 dB / 0.802
0.595
22.86 dB / 0.726
✓ Certified Rudin et al., Phys. A 1992
10 BM4D + gradient 0.643
0.687
26.8 dB / 0.853
0.629
24.39 dB / 0.782
0.612
23.51 dB / 0.751
✓ Certified Maggioni et al., IEEE TIP 2013
11 U-Net-OCT + gradient 0.639
0.792
32.8 dB / 0.951
0.619
24.32 dB / 0.780
0.507
20.6 dB / 0.627
✓ Certified Ronneberger et al., MICCAI 2015 (OCT variant)
12 NLM-OCT + gradient 0.628
0.730
28.44 dB / 0.890
0.632
24.68 dB / 0.792
0.521
20.32 dB / 0.614
✓ Certified Buades et al., Multiscale Model. Simul. 2005
13 FFT-OCT + gradient 0.588
0.612
23.61 dB / 0.754
0.612
23.76 dB / 0.760
0.539
21.62 dB / 0.673
✓ Certified Analytical baseline

Complete score requires all 3 tiers (Public + Dev + Hidden).

Join the competition →
Scoring: 0.4 × PSNR_norm + 0.4 × SSIM + 0.2 × (1 − ‖y − Ĥx̂‖/‖y‖) PSNR 40% · SSIM 40% · Consistency 20%
Public 3 scenes

Full-access development tier with all data visible.

What you get & how to use

What you get: Measurements (y), ideal forward operator (H), spec ranges, ground truth (x_true), and true mismatch spec.

How to use: Load HDF5 → compare reconstruction vs x_true → check consistency → iterate.

What to submit: Reconstructed signals (x_hat) and corrected spec as HDF5.

Public Leaderboard
# Method Score PSNR SSIM
1 ScoreOCT + gradient 0.843 36.51 0.976
2 DiffusionOCT + gradient 0.837 36.33 0.975
3 RetinalFormer + gradient 0.824 34.92 0.967
4 OCT-ViT + gradient 0.819 34.39 0.964
5 SpeckleFormer + gradient 0.806 34.31 0.963
6 U-Net-OCT + gradient 0.792 32.8 0.951
7 OCTA-Net + gradient 0.777 32.09 0.944
8 Speckle-DenoiseNet + gradient 0.752 30.11 0.918
9 NLM-OCT + gradient 0.730 28.44 0.89
10 TV-Denoising + gradient 0.706 27.48 0.869
11 BM4D + gradient 0.687 26.8 0.853
12 Speckle-Lee + gradient 0.655 25.19 0.808
13 FFT-OCT + gradient 0.612 23.61 0.754
Spec Ranges (3 parameters)
Parameter Min Max Unit
dispersion -200.0 400.0 fs²
reference_delay -5.0 10.0 μm
spectral_roll_off -1.0 2.0 dB/mm
Dev 3 scenes

Blind evaluation tier — no ground truth available.

What you get & how to use

What you get: Measurements (y), ideal forward operator (H), and spec ranges only.

How to use: Apply your pipeline from the Public tier. Use consistency as self-check.

What to submit: Reconstructed signals and corrected spec. Scored server-side.

Dev Leaderboard
# Method Score PSNR SSIM
1 SpeckleFormer + gradient 0.783 33.26 0.955
2 OCT-ViT + gradient 0.768 31.66 0.939
3 RetinalFormer + gradient 0.765 31.56 0.938
4 ScoreOCT + gradient 0.759 30.92 0.93
5 DiffusionOCT + gradient 0.719 28.61 0.893
6 Speckle-Lee + gradient 0.654 25.24 0.81
7 OCTA-Net + gradient 0.645 25.08 0.805
8 Speckle-DenoiseNet + gradient 0.637 25.37 0.814
9 TV-Denoising + gradient 0.633 25.0 0.802
10 NLM-OCT + gradient 0.632 24.68 0.792
11 BM4D + gradient 0.629 24.39 0.782
12 U-Net-OCT + gradient 0.619 24.32 0.78
13 FFT-OCT + gradient 0.612 23.76 0.76
Spec Ranges (3 parameters)
Parameter Min Max Unit
dispersion -240.0 360.0 fs²
reference_delay -6.0 9.0 μm
spectral_roll_off -1.2 1.8 dB/mm
Hidden 3 scenes

Fully blind server-side evaluation — no data download.

What you get & how to use

What you get: No data downloadable. Algorithm runs server-side on hidden measurements.

How to use: Package algorithm as Docker container / Python script. Submit via link.

What to submit: Containerized algorithm accepting y + H, outputting x_hat + corrected spec.

Hidden Leaderboard
# Method Score PSNR SSIM
1 SpeckleFormer + gradient 0.731 29.87 0.915
2 RetinalFormer + gradient 0.723 30.02 0.917
3 OCT-ViT + gradient 0.723 30.29 0.921
4 ScoreOCT + gradient 0.705 29.4 0.907
5 DiffusionOCT + gradient 0.682 27.32 0.866
6 Speckle-Lee + gradient 0.651 25.71 0.824
7 BM4D + gradient 0.612 23.51 0.751
8 Speckle-DenoiseNet + gradient 0.596 23.87 0.764
9 TV-Denoising + gradient 0.595 22.86 0.726
10 OCTA-Net + gradient 0.593 22.87 0.726
11 FFT-OCT + gradient 0.539 21.62 0.673
12 NLM-OCT + gradient 0.521 20.32 0.614
13 U-Net-OCT + gradient 0.507 20.6 0.627
Spec Ranges (3 parameters)
Parameter Min Max Unit
dispersion -140.0 460.0 fs²
reference_delay -3.5 11.5 μm
spectral_roll_off -0.7 2.3 dB/mm

Blind Reconstruction Challenge

Challenge

Given measurements with unknown mismatch and spec ranges (not exact params), reconstruct the original signal. A method must be evaluated on all three tiers for a complete score. Scored on a composite metric: 0.4 × PSNR_norm + 0.4 × SSIM + 0.2 × (1 − ‖y − Ĥx̂‖/‖y‖).

Input

Measurements y, ideal forward model H, spec ranges

Output

Reconstructed signal x̂

About the Imaging Modality

OCT is a low-coherence interferometric imaging technique that measures depth-resolved backscattering profiles (A-scans) by interfering sample-arm reflections with a reference mirror. In spectral-domain OCT, the interference spectrum is recorded by a spectrometer and the axial profile is obtained via Fourier transform. Axial resolution is determined by the source bandwidth (typically 3-7 um in tissue) and imaging depth by spectrometer resolution. Dominant artifacts include speckle noise, motion artifacts, and sensitivity roll-off with depth.

Principle

Optical Coherence Tomography uses low-coherence interferometry to produce cross-sectional images of tissue microstructure. A broadband light source (superluminescent diode, ~840 nm or ~1310 nm) is split between sample and reference arms. Interference occurs only when the path lengths match within the coherence length (~5-10 μm), providing axial resolution. Spectral-domain OCT records the spectral interferogram and uses FFT for fast depth-resolved imaging.

How to Build the System

Build or acquire a spectral-domain OCT system: broadband SLD source (center 840 nm, 50 nm bandwidth for retinal; 1310 nm for dermal/cardiac), fiber-based Michelson interferometer, galvo scanner for lateral scanning, and a spectrometer with line camera (2048-4096 pixels) for spectral detection. Calibrate wavelength-to-wavenumber mapping, dispersion compensation, and reference arm delay. For swept-source OCT, use a frequency-swept laser (100-400 kHz sweep rate) and balanced detector.

Common Reconstruction Algorithms

  • FFT-based spectral-domain OCT reconstruction (spectral interferogram → A-scan)
  • Dispersion compensation (numerical or hardware)
  • Speckle reduction (spatial/angular compounding, or deep-learning)
  • Segmentation of retinal layers (graph-based, U-Net, or transformer models)
  • OCT Angiography (OCTA) via decorrelation or phase-variance of repeated B-scans

Common Mistakes

  • Dispersion mismatch between sample and reference arms degrading axial resolution
  • Mirror image artifact from complex conjugate ambiguity in SD-OCT
  • Sensitivity roll-off at deeper imaging depths not compensated
  • Motion artifacts in 3-D OCT volumes (eye motion for ophthalmic OCT)
  • Incorrect refractive index assumption for depth scale calibration

How to Avoid Mistakes

  • Match fiber lengths and add numerical dispersion compensation in reconstruction
  • Place the zero-delay near the sample surface; use full-range OCT if needed
  • Use swept-source OCT for reduced roll-off; optimize spectrometer for uniform sensitivity
  • Apply eye-tracking or motion-correction algorithms; average repeated B-scans
  • Calibrate depth scale with a known-thickness reference standard

Forward-Model Mismatch Cases

  • The widefield fallback applies spatial blur, but OCT acquires spectral interferograms that encode depth via low-coherence interferometry — the interference fringe pattern bears no resemblance to a blurred image
  • OCT depth resolution comes from the broadband source coherence length (~5-10 um), not from spatial PSF — the widefield operator cannot model the axial sectioning, dispersion, or spectral-to-depth FFT relationship

How to Correct the Mismatch

  • Use the OCT operator that models spectral-domain interferometry: y(k) = |E_ref + E_sample(k)|^2, where depth information is encoded in the spectral fringe frequency
  • Reconstruct A-scans via FFT of the spectral interferogram after dispersion compensation and k-linearization; B-scans are formed by lateral scanning

Experimental Setup — Signal Chain

Experimental setup diagram for Optical Coherence Tomography

Experimental Setup

Instrument: Heidelberg Spectralis HRA+OCT / Zeiss Cirrus HD-OCT 5000
Wavelength Nm: 840
Bandwidth Nm: 45
Axial Resolution Um: 5
Lateral Resolution Um: 15
A Scan Rate Khz: 40
Scan Width Mm: 6.0
B Scan Lines: 512
A Scans Per B: 512
Snr Db: 98

Key References

  • Huang et al., 'Optical coherence tomography', Science 254, 1178 (1991)
  • de Boer et al., 'Twenty-five years of OCT', Biomed. Opt. Express 8, 3248 (2017)

Canonical Datasets

  • Duke SD-OCT DME dataset (Chiu et al.)
  • RETOUCH Challenge (retinal OCT)
  • OCTA-500 (Li et al., Scientific Data 2024)

Spec DAG — Forward Model Pipeline

P(low-coherence) → Σ(interference) → D(g, η₁)

P Low-Coherence Source (low-coherence)
Σ Interferometric Sum (interference)
D Spectrometer / Balanced Detector (g, η₁)

Mismatch Parameters

Symbol Parameter Description Nominal Perturbed
ΔGVD dispersion Dispersion mismatch (fs²) 0 200
Δz_r reference_delay Reference delay error (μm) 0 5.0
ΔR spectral_roll_off Spectral roll-off error (dB/mm) 0 1.0

Credits System

40%
Platform Profit Pool
Revenue allocated to benchmark rewards
30%
Winner Share
Top algorithm receives from pool
$100
Min Withdrawal
Minimum payout threshold
Spec Primitives Reference (11 primitives)
P Propagation

Free-space or medium propagation kernel (Fresnel, Rayleigh-Sommerfeld).

M Mask / Modulation

Spatial or spatio-temporal amplitude modulation (coded aperture, SLM pattern).

Π Projection

Geometric projection operator (Radon transform, fan-beam, cone-beam).

F Fourier Sampling

Sampling in the Fourier / k-space domain (MRI, ptychography).

C Convolution

Shift-invariant convolution with a point-spread function (PSF).

Σ Summation / Integration

Summation along a physical dimension (spectral, temporal, angular).

D Detector

Sensor readout with gain g and noise model η (Gaussian, Poisson, mixed).

S Structured Illumination

Patterned illumination (block, Hadamard, random) applied to the scene.

W Wavelength Dispersion

Spectral dispersion element (prism, grating) with shift α and aperture a.

R Rotation / Motion

Sample or gantry rotation (CT, electron tomography).

Λ Wavelength Selection

Spectral filter or monochromator selecting a wavelength band.