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The first 25 slides, exactly as they appear. The full deck has 63 content slides.
Radiology
Abnormal Kidney Size
Built from Obstetric Imaging
What’s inside
7 sections · 63 slides
Why kidney size matters
Kidney growth is predictable, so a measurement can be checked against a chart
- The idea in one slide
- Why measure the kidney at all
- Three ways to measure a kidney
- What a nomogram is
- Four reasons a kidney is the wrong size
The normal fetal kidney
Where it sits, how bright it looks, and how both change as pregnancy goes on
- When the kidneys first appear
- Fetal kidneys beside the lumbar spine at 13 weeks
- The shape of a normal kidney
- How the kidney's brightness changes
- Why brightness is worth watching
- Fetal kidneys in the second trimester
- Comparing the kidney with lung and liver
- Perinephric fat: the outline helper
- Telling the outer and inner kidney apart
- The dark wedges inside the kidney
- Fetal kidneys and renal arteries in the third trimester
- Renal arteries arising from the aorta
How fast the kidney grows
The numbers behind the charts, and the charts themselves
- Kidney growth follows the pregnancy
- 12–13 wk
- Measuring the length
- How to read the charts that follow
- Nomogram for Kidney Length in Millimeters According to Gestational Age
- Nomogram for Kidney Length in Millimeters According to Gestational Age (continued)
- Nomogram for Kidney Length in Millimeters According to Gestational Age (continued)
- Why the two widths matter as well
- Nomogram for Kidney Anterior-Posterior Diameter in Millimeters According to Gestational Age
- Nomogram for Kidney Anterior-Posterior Diameter in Millimeters According to Gestational Age (continued)
- Nomogram for Kidney Anterior-Posterior Diameter in Millimeters According to Gestational Age (continued)
- Nomogram for Kidney Transverse Diameter in Millimeters According to Gestational Age
- Nomogram for Kidney Transverse Diameter in Millimeters According to Gestational Age (continued)
- Nomogram for Kidney Transverse Diameter in Millimeters According to Gestational Age (continued)
When the kidneys look too big
Compensatory hypertrophy and the shape change that gives it away
- What counts as a big kidney
- First steps when the kidneys look big
- When one kidney does the work of two
- Why the other kidney is out of action
- How compensatory hypertrophy unfolds
- The globular clue
- What the width ratio tells you
- Defining it, and how early it shows
When the kidneys look too small
Hypoplasia, back-pressure damage, and the kidneys of a growth-restricted fetus
- Why a kidney may look small
- Damage from urine that cannot get out
- Growth restriction and the kidneys
- Why a small kidney matters later
Working through an abnormal kidney size
Eight questions to answer before settling on “normal”
- Normal is a diagnosis of exclusion
- The eight questions at a glance
- One side, or both?
- Are there other abnormalities?
- Is the amniotic fluid volume normal?
- Are the kidneys brighter than the liver?
- Causes of large echogenic kidneys
- The quiet presentation of dominant polycystic disease
- Mildly enlarged echogenic kidneys in polycystic kidney disease
- How marked is the enlargement?
- Is the collecting system normal?
- Elongated kidney with a duplicated collecting system
- Is the kidney in the right place?
- Are there cysts, and where?
Key points
What to carry away from an abnormal fetal kidney measurement
- Remember about measuring
- Remember about causes
- What a full assessment covers
- References
- References (continued)
- Obstetric Imaging: Fetal Diagnosis and Care, 2nd Edition