Thursday, October 27, 2016

Pyloric stenosis

Measure the muscle only over 3 mm (red line).

Don't measure the mucosa for pyloric stenosis.

Saturday, September 10, 2016

U/S Notes

Fetal Hydrocephalus
Atrium of the lateral ventricle
Greater than 8 mm before 25 weeks
Greater than 10 mm after

Polycystic Ovarian Disease
Greater then 10 mL (l x w x h divided by 2)
12 or more folicles measure 2-9 mm

Ovarian Torsion
Anything larger than 5 cm in any dimension.
Heterogeneous echotexture, more hyperechoic

MSD-CRL  <5 mm  suggests early oligohydramnios

Multiple gestations: check number of fetal poles and yolk sacs
thin vs thick membrane (twin peak sign shows two chorions)

If two embryo in 1 GS must decide if monoamniotic vs diamniotic

Number of YS= number of amnions

If still early in pregnancy and see two fetal poles and 1 yolk sac, reimage 1-2 weeks cuz the 2nd YS may not be seen.

Embryo period ends week 9, fetal period begins week 10.

No abnormal abdominal defect after 12 weeks.  

Monday, August 1, 2016

Role of Imaging in OB Ultrasound

First Trimester (1-12 weeks)
1)  Confirm IUP
2) Date IUP
3) Determine fetal number and plancetation
4) Ectopic?
For bleeding-
Normal IUP
Abortion ( impending, in progress, incomplete, missed)

2nd Trimester (13-27 weeks)
Determine fetal number and viablilty
Evaluate Placenta location
Amniotic fluid
Assess gestational age and growth
Fetal survey
Evaluate adnexa and cervix

3rd Trimester (28- birth)
Vertex or Breech
Type of Placenta
Cervical Os
BPP, growth

100 at 6 weeks
140 8 weeks beyond
get follow up if lower than 85 HR.

Reference: MGH Primer

Sunday, July 17, 2016

Arterial Ultrasound Lower extermity

 Ultrasound Evaluation of Dialysis Catheter

 Normal fisula are monophasic with PSV of 100-400 cm/sec  (EDV of 60-200 cm/s).  Draining veins PSV of 30-100 cm/sec.


Stenosis= increased PSV, decreased lumen.

 Arterial Ultrasound Lower extermity

"Although the US diagnostic criteria for detecting significant stenosis of lower extremity arteries are based on Doppler US findings in many studies , consensus has not been reached on the validated cutoff value. Some studies apply a PSV ratio of 2.0 as a means of differentiating between stenoses of less than 50% diameter reduction and those of greater than 50% reduction, whereas others use 2.5 or 3.0 as a cutoff value. A meta-analysis by Visser and Hunink compared the diagnostic performance of duplex US with that of conventional angiography in detecting significant stenosis from peripheral arterial occlusive disease. Duplex US demonstrated a sensitivity of 87.6% and a specificity of 94.7% and less discriminatory power than MR angiography. Furthermore, duplex US evaluation of the arteries of an entire lower extremity is operator dependent and labor intensive and does not provide a “road map” equivalent to that provided by angiography. Thus, duplex US would be expected to play only a supplementary role in evaluating restricted segments of lower extremity arteries."

 Duplex US Criteria for Diagnosis of Stenosis of Lower Extremity Arteries


Aortic Ultrasound.


Waveforms obtained from the distal abdominal aorta near the iliac bifurcation usually have a higher-resistance flow pattern, reflecting the peripheral resistance of the lower extremity arteries. Waveforms obtained from the peripheral arteries demonstrate a triphasic character in the resting state with reversal of flow during diastole. This is due to branching into smaller arteries and capillary beds. The average velocity range for the abdominal aorta is 60 to 100 cm/sec.  Report if velocity is over 200 cm/sec

Stroke Evolution on MRI

Dating stroke on MRI.

AJNR Am J Neuroradiol. 2001 Apr;22(4):637-44.Evolution of ap