λ h⁻¹
Dr. Guido Maria Meduri Campus Biomedico University
Rome · Italy
EXPERIMENTAL SOFTWARE — USE AT YOUR OWN RISK.  This tool is provided for educational and professional reference purposes only. Results may contain errors. Always verify every calculation independently before clinical use. Do not make clinical decisions based solely on this software. The authors accept no liability for any consequences arising from its use.
Nuclear Medicine Toolkit — About this tool
A comprehensive, browser-based clinical calculator suite for nuclear medicine departments. All computations run locally — no data is transmitted or stored externally.

▸ Dose Preparation  Syringe pre-calibration computes the activity to draw at preparation time to deliver a precise prescribed dose at injection time, fully accounting for physical decay (Asyringe = Adesired × e+λ·Δt). Certificate decay calculates residual activity from the vial calibration certificate at any target date and time. Volume & dilution derives draw volumes and final concentrations from stock solutions. The decay curve is expressed in real clock time from preparation to end of study, with a marker at administration time.

▸ Patient Dosimetry  Weight-based and pediatric (EANM dosage card method) activity prescription with configurable maximum caps. Effective half-life calculated from physical and biological components: Teff = Tphys·Tbiol / (Tphys+Tbiol). Patient residual activity over time and time-to-discharge threshold estimation.

▸ Radiation Protection  Point-source dose rate via inverse square law (H = Γ·A/d²) with isotope-specific Γ constants. Shielding thickness calculator in lead and concrete (HVL/TVL). Time to reach regulatory release threshold. Breastfeeding interruption guidance per IAEA Safety Reports Series No. 40 & EANM guidelines.

▸ PET Quantification  Standardised Uptake Value normalised to body weight (SUVbw), lean body mass (SUVlbm/SUL, Janmahasatian formula), and body surface area (SUVbsa, Du Bois). Dead time correction for paralysable and non-paralysable detector models. Radiochemical purity QC with configurable pass/fail threshold.

▸ Reference Tables  Isotope-specific decay and pre-calibration correction factors, half-life comparison chart, and physical data (T½, gamma constant Γ, HVL in Pb and concrete) for 12 clinically used radionuclides: ¹&sup8;F, &sup9;&sup9;¹³Tc, ¹²³I, ¹³¹I, &sup6;&sup7;Ga, ¹¹¹In, ²&sup0;¹Tl, &sup6;&sup8;Ga, &sup8;²Rb, &sup8;&sup9;Sr, ¹&sup7;&sup7;Lu, ²²³Ra.

⚠ For professional use only. Always verify results against institutional protocols and current regulatory guidelines. The authors disclaim any liability for clinical decisions based solely on this tool.
γ constant: μSv·m²·MBq⁻¹·h⁻¹ HVL Pb: mm
Syringe Activity — Pre-calibration Calculator
Preparation time
When you fill the syringe
Administration time
When you inject the patient
Desired activity at injection (MBq)
Activity to draw at preparation time
— MBq
Decay from Calibration Certificate
Certificate activity (MBq)
Certificate date & time
Target date & time

Fill in all fields to calculate.

Volume & Dilution Calculator
Vial total activity (MBq)
Vial volume (mL)
Activity to draw (MBq)
Dilution
Stock concentration (MBq/mL)
Stock volume to use (mL)
Final volume (mL)
Decay Curve from Dose Preparation Time
Activity by Patient Weight
Reference dose/kg (MBq/kg)
¹⁸F-FDG ≈ 4 | ⁹⁹ᵐTc bone ≈ 11 | MAG3 ≈ 3.7
Patient weight (kg)
Maximum activity cap (MBq)
Pediatric Dose — EANM Dosage Card Method
Adult reference activity (MBq)
Patient weight (kg)
Minimum activity (MBq)
Effective Half-Life & Biological Clearance
Physical T½ (h) — auto from isotope
Biological T½ (h)
FDG brain ≈ 109h · ¹³¹I thyroid ≈ 80d (1920h)
Administered activity (MBq)
Residual Activity in Patient & Clearance Time
Administered activity (MBq)
Effective T½ (h)
← Auto-filled from Effective T½ above
Discharge threshold (MBq)
Typical: 25 MBq · Verify local protocol
Dose Rate at Distance — Point Source
Activity (MBq)
Distance (m)
Γ constant (μSv·m²·MBq⁻¹·h⁻¹)
Auto-set from isotope
H = Γ × A / d² · Doubling distance → dose rate ÷ 4
Shielding Calculator — HVL & TVL
Initial dose rate (μSv/h)
Target dose rate (μSv/h)
HVL in Pb (mm)
Auto-set from isotope
HVL in concrete (cm)
Time to Reach Release / Discharge Threshold
Initial activity (MBq)
Threshold activity (MBq)
IAEA: ~25 MBq · EU directive varies
Effective T½ (h)
Breastfeeding Interruption Guidance — IAEA / EANM
IsotopeApplicationInterruption
Reference: IAEA Safety Reports Series No. 40 & EANM guidelines. Always verify with current institutional protocol.
SUV Calculator — Body Weight · Lean Mass · BSA
Tissue concentration (kBq/mL)
Injected activity (MBq)
Decay-corrected to scan time
Body weight (kg)
Height (cm)
SUV_lbm (SUL) recommended for serial studies and obese patients. LBM via Janmahasatian formula.
Dead Time Correction — Paralysable & Non-Paralysable
Measured count rate N_obs (cps)
Dead time τ (μs)
Model
Radiochemical Purity & Labelling Efficiency
Total activity measured (MBq)
Free / unbound activity (MBq)
Minimum acceptable purity (%)
Decay Factor Table
Elapsed time Residual (%) Decay factor (×) Pre-cal factor (×) T½ elapsed
Half-Life Comparison — All Isotopes
Isotope Reference Data
IsotopeDecay Γ (μSv·m²·MBq⁻¹·h⁻¹)HVL Pb (mm) HVL concrete (cm)Clinical use