Official implementation of the paper "Memory-efficient High-resolution OCT Volume Synthesis with Cascaded Amortized Latent Diffusion Models" Arxiv.

Our codebase builds on LatentDiffusion, MedicalDiffusion, and MONAI.

The proposed method is the first to synthesize 3D volumetric images with a resolution of 512^3 using only 24GB of GPU memory.

Data

Public data 'OCTA-500' can be downloaded at: https://ieee-dataport.org/open-access/octa-500.

The partitions of data of our experiments are provided at train_volume_names.json and test_volume_names.json.

Train

Acutally, there are many routes to train our model. Here we provide a more stable version recently discovered, which differs slightly from the version described in the paper.

1. Train a 2D VQVAE. Run train_VQVAE2D.py and fill following args:

parser.add_argument("--exp_name", type=str, default='dirname')
parser.add_argument('--result_root', type=str, default='path/to/dir')
parser.add_argument('--data_root', type=str, default='path/to/OCT')

2. Train NHVQVAE. Run train_NHVQVAE.py and fill following args:

   parser.add_argument("--exp_name", type=str, default='model name')
   parser.add_argument('--result_root', type=str, default='path/to/save/dir')
   parser.add_argument('--data_root', type=str, default='path/to/OCT')
   parser.add_argument('--image_npy_root', type=str,default='path/to/volume/npy')

3. Train LDM3D. Run train_LDM3D.py and fill following args:

   parser.add_argument("--exp_name", default='model name')
   parser.add_argument('--result_root', type=str, default='path/to/save/dir')
   parser.add_argument('--first_stage_ckpt', type=str,default='path/to/NHVQVAE/ckpt')
   parser.add_argument('--latent_root', type=str,default='path/to/NHVQVAE/latent')

4. Train LDM2D_refiner. Run train_LDM2D_refiner.py and fill following args:

   parser.add_argument("--exp_name", type=str, default='dirname')
   parser.add_argument('--result_root', type=str, default='path/to/dir')
   parser.add_argument('--first_stage_ckpt', type=str, default='path/to/vqgan2d/ckpt')
   parser.add_argument('--latent_1_root', type=str, default='path/to/3D/latent')
   parser.add_argument('--latent_2_root', type=str, default='path/to/2D/latent')

5. Train multi-slice decoder. Run train_VQVAE_w_adaptor.py and fill following args:

   parser.add_argument("--exp_name", type=str, default='model name')
   parser.add_argument('--result_root', type=str, default='path/to/save/dir')
   parser.add_argument('--image_npy_root', type=str, default='path/to/volume/npy')

Test

We split the generation procedure into three stages.

1. Generate 3D latents. Run test_LDM3D.py and fill following args:

   parser.add_argument('--result_save_dir', type=str, default='path/to/save/dir')
   parser.add_argument('--first_stage_ckpt', type=str,
   default='path/to/NHVQVAE/ckpt')
   parser.add_argument('--ldm1_ckpt', type=str,
   default='path/to/LDM3D/ckpt')
   parser.add_argument('--ldm2_ckpt', type=s

2. Refine latents. Run test_LDM2D_refiner.py and fill following args:

   parser.add_argument('--result_save_dir', type=str, default='path/to/save/dir')
   parser.add_argument('--first_stage_ckpt', type=str, default='path/to/NHVQVAE/ckpt')
   parser.add_argument('--ldm1_ckpt', type=str, default='path/to/LDM3D/ckpt')
   parser.add_argument('--ldm2_ckpt', type=str, default='path/to/LDM2D_refiner/ckpt')
   datamodule = testDatamodule(latent_root='path/to/ldm1_latent')

3. Decode latents to images. Run test_decodebyMSDecoder.py and fill following args:

   parser.add_argument('--result_save_dir', type=str,default='path/to/save/dir')
   parser.add_argument('--result_save_name', type=str, default='save name')
   parser.add_argument('--first_stage_ckpt', type=str, default='path/to/VQVAE_w_adaptor/ckpt')
   parser.add_argument('--ldm2_latent', type=str, default='path/to/saved/ldm2_latent')