Recent revisions
Our editorial team continuously reviews the library against authoritative sources. Here are the notable revisions — corrections, sharper framing, and new material. Routine upkeep (dead-link fixes, duplicate merges) isn't listed.
3710
Cards in library
3631
Sources verified
3111
Reference images
0
Reviewed this week
3710
Audited to date
510
Corrections published
What do these numbers mean?
- Cards in library:
- Total study cards currently available across every section.
- Sources verified:
- Cards linked to an authoritative reference we've confirmed.
- Reference images:
- Cards with at least one linked teaching image (e.g. Radiopaedia).
- Reviewed this week:
- Cards an editor re-checked against sources in the last 7 days.
- Audited to date:
- Cards an independent reviewer has checked for accuracy and structure.
- Corrections published:
- Entries in the public updates log where we fixed or sharpened a card.
Comma sign (cecal volvulus)
Removed false-precision claim that CT sensitivity approaches 100%; CT-sign sensitivity is variable, so replaced with qualitative statement that CT is far more sensitive than radiography.
MASS criteria in metastatic RCC
Corrected source provenance: card teaches the MASS >=40 HU favorable-response threshold but cited the SACT paper (AJR.09.2941). Repointed source_url and body.source to the MASS paper (Smith AD et al, AJR 2010;194(6):1470-1478, DOI 10.2214/AJR.09.3456). The >=40 HU figure was independently verified against the MASS paper and left unchanged (no numeric alteration).
Gallbladder polyp surveillance
Corrected source attribution from SRU consensus to the ESGAR/EAES/EFISDS/ESGE joint guideline to match the card content and URL.
Gallbladder polyp thresholds
Corrected primary source attribution to the ESGAR/EAES/EFISDS/ESGE joint guideline (SRU distinction retained in the answer text).
Gallbladder polyp management
Corrected source label from SRU consensus to the 2022 joint European guideline, resolving a conflict with the stem attribution.
Small, homogeneous, T2-hypointense renal mass
Replaced an unsourced absolute HU enhancement figure with the sourced qualitative point that papillary RCC shows low-level enhancement below cortex.
Huang-Tseng classes: emphysematous pyelitis vs pyelonephritis
Corrected the poor-outcome threshold to two or more risk factors, removed diabetes from the four prognostic risk factors (thrombocytopenia, acute renal failure, altered consciousness, shock), and replaced unverifiable modality-sensitivity percentages with qualitative language.
Hypoattenuating halo sign: a finding that argues against gallbladder carcinoma
Added source attribution for the intramural hypoattenuating-nodule and continuous-mucosal-line differentiators, confirming the claim against the foundational CT series.
Breast implant-associated anaplastic large cell lymphoma (BIA-ALCL)
Corrected ultrasound performance: the ~84% sensitivity / ~75% specificity applies to the peri-implant effusion, with sensitivity falling to ~46% for a discrete capsular mass, so a mass-negative scan does not exclude disease.
Halo sign: hemorrhagic metastases vs angioinvasive fungus
Corrected attribution of the original CT halo sign / angioinvasive aspergillosis description to Kuhlman et al. 1985 (the cited 1994 Radiology 190(2) paper is Primack/Muller).
Breast density categories and reporting
Corrected the extremely-dense breast cancer risk estimate to the sourced ~2-fold-vs-scattered (roughly 4-fold-vs-fatty) figure and removed an unverifiable DBT detection-rate pair.
Neck CTA carotid plaque grading
Attached the primary citation supporting the Plaque-RADS 4c odds ratio quoted in the explanation; the figure and confidence interval were independently re-checked against the source study.
Radiation LR-TR categories
Completed the radiation treatment response category list to include LR-TR Nonevaluable alongside Viable, Nonviable, and Nonprogressing, and stated the enhancement criterion that separates Nonprogressing from Viable.
CT dose optimization (ALARA)
Added the justification-before-optimization framing and clarified that CTDIvol/DLP are phantom-referenced scanner output metrics while SSDE is the size-corrected patient metric.
Fetal radiation dose in pregnancy
Rebalanced answer choices so the correct option is no longer the longest and most detailed; answer key unchanged.
Fetal radiation effects
Rebalanced answer choices to remove length cueing and strengthened the implausible distractor; answer key unchanged.
I-123 MIBG imaging for suspected pheochromocytoma/paraganglioma
Replaced a single vague drug-withdrawal window with the guideline intervals (most agents 24-72 h, labetalol about 10 days), added a preparation/dosing summary, and noted that DOTATATE PET is now the first-line localizer with MIBG reserved for therapy planning.
Sonographically indeterminate adnexal mass - O-RADS MRI protocol
Replaced the shorthand curve descriptions with the full O-RADS time-intensity criteria for categories 3, 4 and 5 and flagged that absence of a plateau alone does not separate low risk from high risk; added the missing protocol summary and the b-value units.
Aggressive midline sacral / sacrococcygeal mass in an adult
Added the missing lead-in, which now names solitary-versus-multifocal as the feature separating chordoma from metastasis and myeloma before moving to matrix and lesion epicentre.
Benign breast calcification features
Updated the answer and explanation to the current BI-RADS rim descriptor, replacing the retired lucent-centered and eggshell terms and aligning the card with the rest of the breast calcification set.
Renal angiomyolipoma thresholds
Relabelled the 4 cm and 5 mm figures as heuristics with their key caveat and added the tuberous sclerosis pathway, where mTOR inhibition rather than embolization is first-line.
Deauville PET response scoring
Explanation now labels the score-3 rule as context-dependent and adds the response-adapted de-escalation caveat, aligning it with the topic's complete-metabolic-response card.
Radiation in pregnancy: fetal dose thresholds and counseling
Fetal CT dose range aligned to the ACOG Committee Opinion 723 figure, CNS dose thresholds restated to the published IQ-decrement and severe-disability values, and the "no study exceeds" claim qualified for multiphase and interventional exposures.
Incidental small solid pulmonary nodule
Explanation corrected at the size boundary: no routine follow-up applies below 6 mm, not at 6 mm or less, and the guideline exclusions were added.
Fetal CNS radiosensitivity
One-line answer expanded with the dose thresholds that make the 8-15 week window meaningful and the counseling implication.
Lead-time vs length-time bias
Prompt reworded as a question distinct from the title, and the answer now names disease-specific mortality as the outcome that avoids both biases.
AUC and disease prevalence
Prevalence independence kept but paired with the case-mix (spectrum bias) exception and contrasted with PPV/NPV.
Bosniak classification of cystic renal masses (v2019)
Corrected the class II criteria: under version 2019 calcification of any type is permitted in a thin-walled cyst, replacing the outdated "fine calcification" restriction, and class I now notes that a thin wall may enhance.
Radiation cataract lens dose limit
Added the single-year 50 mSv cap that accompanies the 20 mSv five-year average, noted the earlier 150 mSv limit for contrast, and attached the ICRP citation.
Diagnostic reference levels (DRLs)
Verified the 75th-percentile DRL and median achievable-dose figures against the ACR-AAPM US CT reference levels and attached the citation.
DRL vs achievable dose
Verified the percentile figures against the ACR-AAPM US CT reference levels and attached the citation.
Kappa statistic and interobserver agreement
Verified the Landis and Koch agreement bands against the original Biometrics paper and attached the primary citation.
Kappa 0.61-0.80
Verified the agreement bands against the original Landis and Koch paper and attached the primary citation.
Fish (codfish) vertebra
Replaced the general-encyclopedia reference with peer-reviewed and case-library sources, and added the caveat that biconcave vertebrae also occur in sickle cell and other marrow-replacing disease rather than osteoporosis alone.
Hypervascular / avidly enhancing adrenal mass
Added the missing teaser leading with the discriminator between the top two entries, ranked the differential with imaging features, and replaced a mislabeled mnemonic with a pitfalls line.
Functional imaging choice in suspected pheochromocytoma/paraganglioma
Added the missing teaser leading with the SDHB decision point and shortened an unwieldy title.
Salt-and-pepper sign
Sign is now attributed to its established entity, paraganglioma including head-and-neck lesions, with a note that it indicates hypervascularity rather than a specific tumor.
Pheochromocytoma pre-procedure blockade
Added the boundary of the rule: alpha-blockade is required before resection but not before IV nonionic contrast CT, with a citation.
Pheochromocytoma light-bulb sign
Corrected the stated frequency of T2 hyperintensity and its direction, replaced an unsourced range with a cited figure, and added the false-positive pitfall.
Pheochromocytoma rule of 10s
Card recited the rule of 10s as fact; now framed as a legacy heuristic with the hereditary and malignant limbs corrected against current genetics and WHO 2022 terminology.
O-RADS MRI 4 malignancy risk
Added the criteria that earn a category 4 score alongside the risk figure, so the card teaches assignment rather than a bare number.
O-RADS MRI enhancement
Added how the non-dynamic 30-40 s substitute maps to categories 4 and 5 and noted that it cannot separate 3 from 4.
O-RADS MRI categories
Added the published positive predictive values for categories 3, 4 and 5 to match the rest of the topic.
O-RADS MRI time-intensity curve
Replaced the shorthand curve descriptions with the full three-curve definitions referenced to outer myometrium.
O-RADS MRI 2 lesions
Added the exception that an endometrioma or dermoid with enhancing solid tissue is no longer category 2.
Pheochromocytoma: An Imaging Chameleon
Replaced an unsourced T2 signal range with the cited figure and corrected its direction, reframed the rule of 10s as a legacy heuristic with current hereditary rates, and added the WHO 2022 metastatic terminology.
Pheochromocytoma
Summary now states that T2 signal cannot exclude the diagnosis and adds current WHO terminology and hereditary framing.
O-RADS MRI dynamic contrast technique for a sonographically indeterminate adnexal mass
Corrected the benign solid-tissue rule to require low signal on both T2 and high-b DWI rather than DWI alone, added the missing summary, and specified how the non-dynamic substitute maps to categories 4 and 5.
O-RADS MRI Risk Stratification System: Guide for Assessing Adnexal Lesions from the ACR O-RADS Committee
Diagnostic-performance figures re-attributed to the separate multicenter validation cohort with citation; added the curve-to-score mapping and the non-dynamic-protocol caveat.
CT dose metrics: CTDIvol, DLP, SSDE
Corrected the definition of effective diameter to the square root of AP x lateral, added the TG-220 water-equivalent diameter update, attached AAPM Report 96 k-factors, and clarified that SSDE is not an organ dose.
CT dose reference values (adult)
Replaced unsourced typical-dose ranges and an unsupported achievable-dose figure with cited ACR accreditation reference levels and ACR Dose Index Registry values, and added the phantom caveat.
Dose length product (DLP)
Attached AAPM Report 96 as the source for the DLP-to-effective-dose k-factors and stated the chest and abdomen values explicitly.
Size-specific dose estimate
Added the TG-220 water-equivalent diameter update and the key limits of SSDE (not an organ dose, no scan-length correction), and replaced a non-authoritative citation.
Chordoma histology
Reframed physaliphorous cells as characteristic rather than diagnostic and named brachyury as the confirmatory marker.
Chordoma origin and location
Softened an absolute claim about midline-only occurrence and added the practical corollary that an off-midline lesion favours chondrosarcoma.
AML hemorrhage risk features
Corrected the logic from "size and aneurysm" to independent risk factors, and labelled the 4 cm figure as a heuristic with its main exception.
Spectrum of Renal Angiomyolipoma with Radiologic-Pathologic Correlation
Aligned the hemorrhage-risk size threshold with the classic 4 cm figure used elsewhere in this topic and cited it; expanded the limitation noting the threshold's single-series origin and known challenges.
BI-RADS calcification distribution and suspicion ladder
Updated superseded descriptors (popcorn, milk of calcium) to the current BI-RADS v2025 lexicon so the card agrees with the other calcification cards, and clarified that morphology outranks distribution in the biopsy decision.
Suspicious calcification distribution
Removed an unsupported "roughly twice as likely" risk multiplier in favour of qualitative framing, and added the ductal-anatomy rationale.
DCIS calcifications
Removed a false-precision ">85%" figure; published series report a wide range, so the answer is now qualitative.