Tools
Radiology Calculators
For educational and reference use only. These calculators do not replace clinical judgement, local protocols, or a qualified clinician. Verify every result independently before it informs patient care.
Body imaging
Estimated GFR from serum creatinine, the race-free 2021 equation.
Per-lobe ellipsoid volume on ultrasound, with goitre thresholds.
Ellipsoid gland volume and PSA density (PI-RADS input).
Testicular (Lambert) or ovarian (ellipsoid) volume on ultrasound.
Ellipsoid bladder volume from three ultrasound dimensions.
Ellipsoid splenic volume and splenic index from three dimensions.
Standard total liver volume from body-surface area (Vauthey).
Absolute & relative washout to characterise a lipid-poor adenoma.
Signal-intensity index for microscopic fat in a lipid-rich adenoma.
Thyroid nodule risk level and FNA guidance from ultrasound features.
Prostate MRI assessment category from zone, T2, DWI and DCE.
HCC observation category (LR-3/4/5) from APHE, size and major features.
Renal cystic mass class, malignancy risk and management.
Colonic (C0–C4) category and management from the largest finding.
Inflammation + necrosis + extrapancreatic complications → mCTSI (0–10).
Anatomical complexity of a renal mass (4–12).
Women's & obstetric imaging
Naegele’s rule: due date and current gestational age from the LMP.
First-trimester dating from crown–rump length (Robinson–Fleming).
Sonographic EFW from BPD, HC, AC and FL (Hadlock 4-parameter).
Sum of the four-quadrant deepest pockets, with fluid interpretation.
Cardiothoracic imaging
Follow-up recommendation for an incidental pulmonary nodule.
Lung-cancer-screening category from nodule type and size.
Coronary CTA category from maximal stenosis.
Neuroradiology
Percentage internal-carotid stenosis by the NASCET or ECST method.
Cavernous sinus invasion grade of a pituitary macroadenoma.
Musculoskeletal imaging
Findings-based management category for a solitary CT bone lesion.
Morphological fracture type of a thoracolumbar injury.
Emergency radiology
Splenic injury grade from CT findings (highest feature governs).
Liver injury grade from CT findings (highest feature governs).
Renal injury grade from CT findings (highest feature governs).
Supportive sonographic findings for acute cholecystitis.
Nuclear medicine
Semiquantitative ¹²³I-mIBG skeletal + soft-tissue score (0–30).
Vascular & interventional
Arterial resistive index from peak-systolic and end-diastolic velocity.
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