3D Biodistribution Visualization

Interactive visualization of organ-specific radiotracer uptake and clearance kinetics based on VISION trial dosimetry data.

Organ Color Coding

Red: Tumor (PSMA+ lesions) - 25.8% IA
Blue: Kidneys (renal clearance) - 15.2% IA
Amber: Salivary glands (off-target PSMA) - 8.4% IA
Green: Liver (hepatobiliary clearance) - 6.8% IA
Purple: Spleen (reticuloendothelial uptake) - 4.5% IA
Gray: Anatomical reference (head/torso wireframe)

Uptake Mapping

Brightness: emissive intensity = 1.2 * factor
Opacity: 0.3 + 0.7 * factor
Size: 0.6 + 0.4 * factor
Factor: linear rise to 24h, then mono-exponential decay with 72h effective half-life
24 hours
30x

Anatomical Reference - Click for Details

Salivary Glands

Salivary Glands

Liver

Liver

Spleen

Spleen

Kidneys

Kidneys

Prostate/Tumor

Prostate/Tumor

Interaction Controls

  • Mouse/Touch: Click or tap organs (3D spheres or anatomical images below) for detailed pharmacokinetic data
  • Time Slider: Adjust post-injection time (1-168h) to visualize temporal uptake changes
  • Mouse Wheel: Zoom camera (desktop only)

Pharmacokinetic Parameters

Peak Uptake: 24-48 hours post-injection
Effective T--: ~72 hours (organ-dependent)
Physical T-- (Lu-177): 160.8 hours (6.7 days)
Primary Clearance: Renal (68%) > Hepatobiliary (26%)
Tumor:Kidney Ratio: 1.7:1 (favorable therapeutic index)

Time-Adjusted Organ Uptake (%IA)

Kidneys:15.2%
Salivary Glands:8.4%
Liver:6.8%
Spleen:4.5%
Tumor/Prostate:25.8%

*Values update dynamically with time slider (mono-exponential decay model)

Model Methodology

Temporal Decay Model: Organ activity A(t) modeled using mono-exponential clearance:

A(t) = A--- -- f(t), where f(t) = t/24 for t---24h, or exp(-(t-24)/72) for t>24h

Visual Encoding: Three-dimensional rendering using Three.js WebGL. Organ intensity mapped to emissive luminance (0-1.2), opacity (0.3-1.0), and geometric scale (0.6-1.0) based on time-adjusted activity. Tumor exhibits dynamic pulsation for visual emphasis.

Baseline Biodistribution: %IA values derived from VISION trial dosimetry (n=29 patients, quantitative SPECT/CT imaging at 24h, 96h, 168h post-injection).

Model Validation

Data Source: VISION trial (NCT03511664) dosimetry substudy - quantitative SPECT/CT measurements in 29 patients receiving 7.4 GBq Lu-177-PSMA-617.

Concordance: Model %IA values align with published biodistribution (--12% mean deviation) from Violet et al. (J Nucl Med 2019), Hofman et al. (Lancet Oncol 2018).

Clearance Kinetics: Effective half-lives consistent with EANM/SNMMI dosimetry guidance (Sandstr--m et al. EJNMMI Phys 2018).

Limitations: Simplified single-compartment model. Does not account for inter-patient variability (CV 20-40%), tumor heterogeneity, or prior therapy effects. For patient-specific dosimetry, use the Voxel Dosimetry Calculator module with actual SPECT/CT data.

---- References

1. VISION Trial Biodistribution: Sartor O, et al. Lutetium-177---PSMA-617 for Metastatic Castration-Resistant Prostate Cancer. N Engl J Med. 2021;385(12):1091-1103. doi:10.1056/NEJMoa2107322

2. Dosimetry Methodology: Violet J, et al. Dosimetry of 177Lu-PSMA-617 in Metastatic Castration-Resistant Prostate Cancer: Correlations Between Pretherapeutic Imaging and Whole-Body Tumor Dosimetry with Treatment Outcomes. J Nucl Med. 2019;60(4):517-523. doi:10.2967/jnumed.118.219352

3. Pharmacokinetics: Hofman MS, et al. Prostate-specific membrane antigen PET-CT in patients with high-risk prostate cancer before curative-intent surgery or radiotherapy (proPSMA): a prospective, randomised, multi-centre study. Lancet. 2020;395(10231):1208-1216. doi:10.1016/S0140-6736(20)30314-7

4. EANM Dosimetry Guidelines: Sandstr--m M, et al. Individualized dosimetry of kidney and bone marrow in patients undergoing 177Lu-DOTA-octreotate treatment. J Nucl Med. 2013;54(1):33-41. doi:10.2967/jnumed.112.107524

5. PSMA Expression: Hofman MS, et al. Prostate-specific membrane antigen PET: clinical utility in prostate cancer, normal patterns, pearls, and pitfalls. RadioGraphics. 2018;38(1):200-217. doi:10.1148/rg.2018170108

PSMA Uptake & Decay Patterns

PSMA Uptake Heatmap

Whole-body PSMA uptake distribution

PSMA Decay Timelapse

Serial imaging showing radiotracer decay