Urinary tract / Kidneys — Reference values: Adult kidney — bipolar length, Length difference between kidneys, Renal parenchyma — thickness, Renal cortex — thickness.
Brazil: CBR defines kidneys and bladder as the exam scope; ureters/adrenals are reported when abnormal, and post-void residual is added by indication or request. US/Europe: interpret PVR cautiously because thresholds vary across guidance.
| Measurement | Usual value | Note |
|---|---|---|
| Adult kidney — bipolar length | 9–12 cm | varies with height, sex, age and body habitusconsensus normal: 9–12 cmborderline/context: 8–9 ou 12–13 cmlikely abnormal: <8 ou >13 cm✓ applied automatically in the reportSource: StatPearls / Radiology Key / Rumack |
| Length difference between kidneys | ≤ 1,5 cm | larger difference suggests unilateral disease or anatomic variation to correlatenormal: ≤1,5 cmabnormal: >1,5 cmSource: StatPearls / AccessMedicine |
| Renal parenchyma — thickness | 1,3–2,5 cm | less than 1.0 cm is compatible with relevant thinningpreserved: ≥1,3 cmborderline: 1,0–1,2 cmthinned: <1,0 cm✓ applied automatically in the reportSource: PMC Doppler kidney disease / StatPearls |
| Renal cortex — thickness | 7–15 mm | varies by technique; interpret with echogenicity and kidney sizepreserved: ≥10 mmtechnique/age zone: 7–9 mmmarked thinning: <7 mmSource: StatPearls / nephrology ultrasound reviews |
| Bladder wall — full bladder | ≤ 3 mm | 3–5 mm depends on filling; >5 mm with a full bladder is suspiciousnormal full: ≤3 mmborderline/filling: 3–5 mmthickened: >5 mm✓ applied automatically in the reportSource: EFSUMB bladder chapter / StatPearls |
| Bladder volume for evaluation | 200–300 mL | partially full bladder improves wall and lesion assessmentSource: EFSUMB bladder chapter |
| Bladder volume calculation | comprimento × largura × profundidade × 0,52 | some protocols use different coefficients depending on bladder shapeSource: StatPearls PVR / bladder volume studies |
| Post-void residual | mL · ICS mL | Reference: ICS — there is no universal cutoff✓ applied automatically in the reportSource: ICS teaching module 2016 / DOI 10.1002/nau.22671 |
| Measurement | Reference | Context |
|---|---|---|
| mL | Reference: ICS — there is no universal cutoff | Assistive quick-reference content. Values vary by source, age and technique — confirm against the literature and your clinical judgment before use. |
Assistive quick-reference content. Values vary by source, age and technique — confirm against the literature and your clinical judgment before use.
Source: ICS teaching module 2016 / DOI 10.1002/nau.22671
| Grade | Finding | Interpretation |
|---|---|---|
| Absent | Nondilated collecting system | Normal when there is no obstructive context. |
| Mild | Early calyceal/pelvic dilatation, papillae preserved | Real finding, but may depend on hydration, full bladder or variant. |
| Moderate | Rounded calyces and effaced papillae | Higher suspicion for obstruction; correlate with pain, ureter and ureteric jet. |
| Severe | Confluent calyces and thinned cortex (<1 cm) | Consensus important abnormality; look for obstructive cause. |
Grading is partly subjective; differentiate from extrarenal pelvis and parapelvic cysts.
Source: StatPearls Urinary Tract Ultrasound / SFU concepts
| Class | Description | Malig. risk | Note |
|---|---|---|---|
| I | Simple cyst: anechoic, thin wall and posterior enhancement | ~0% | No follow-up when typical. |
| II | Few thin septa or fine calcification, no solid component | <1% | Generally benign. |
| IIF | More septa or mild thickening: needs follow-up | ~5–10% | Gray zone; CT/MRI or contrast improves characterization. |
| III | Thick or irregular enhancing wall/septa | ~50% | Indeterminate/suspicious. |
| IV | Enhancing solid component | ~90–100% | High suspicion. |
Bosniak was created for contrast CT/MRI. On noncontrast ultrasound, use as descriptive triage and recommend contrast imaging if complex.
Source: Bosniak v2019 (Radiology/RSNA) / StatPearls Urinary Tract Ultrasound