Transcript Estimation of Uterine Size. How Good Are Our Examination Skills?

A Comparison of Two
Techniques Used to Estimate
Uterine Size Prior to
Hysterectomy
L. Ceballos and C. deRiese
Texas Tech University Health Science
Center Department of Obstetrics and
Gynecology, Lubbock, TX
Introduction
 600,000
hysterectomies per year
 Modes of hysterectomy include transabdominal, trans-vaginal, laparoscopic
assisted, and total laparoscopic
Modes of assessment
 Bimanual
exam
 Ultrasound
 Objectives:
to determine how
accurate both bimanual exams and
ultrasound exams are in
determining estimated uterine
weight
 Study Design: retrospective chart
review performed at Texas Tech
University Health Sciences Center
and the affiliated hospital,
University Medical Center
Materials and Methods
 Chart
review from the year 2003- 2007
 Information retrieved
– Estimated uterine size by physical exam
– Pelvic ultrasound measurements
– Actual uterine weight from pathology reports
– Height and weight to calculate BMI
 Statistics
used: linear regression analysis
388 hysterectomies
that met the
inclusion criteria
6 charts with no
documented
pathology weight
366 charts
reviewed
185 charts with
documented bimanual
estimation of uterine
size
22 charts not
accessible
129 charts with pelvic
ultrasound performed
no more than three
month prior to
surgery
Texas Tech Chart
Number of
Patients
Uterine Size
Mean Uterine
Weight
Standard
Deviation
12
6
93
+/- 43
45
8
116
+/-43
50
10
163
+/-85
40
12
168
+/-66
20
14
286
+/-195
6
16
462
+/-271
Preoperative clinical uterine size along with
mean uterine weights of specimens

nongravid ut size(wk)
6
8
10
12
14
16
18
20
22
24
26
*Harb and Adam
mean ut weight(g)
113
141
172
233
321
465
747
1046
1246
1459
1730
stand deviation(g)
+/-48
+/-66
+/-82
+/-113
+/-160
+/-209
+/-311
+/-464
+/-588
+/-479
+/-713
Clinical exam compared to
actual weights
pathology weight (grams)
clinical exam estimates compared to actual weights
900
800
700
600
500
400
300
200
100
0
0
5
10
Bim anual exam (w eeks)
15
20
Ultrasound compared to actual
weights
Ultrasound estimates compared to actual weights
400
350
pathology uterine weight (grams)
300
250
200
150
100
50
0
0
200
400
ultrasound uterine weight (grams)
600
Results by Linear Regression
Analysis


Statistical analysis indicated R squared of 0.9773 when
comparing the bimanual method to the pathological weight
and R squared of 0.8033 when comparing the Ultrasound
method to the pathological weight
The statistical analysis indicated R squared of 0.9032 when
comparing obese subjects and R squared of 0.7833 in the
non-obese subjects
Conclusion



Bimanual exam was more accurate at predicting uterine
weights compared to pelvic ultrasound, although this was
not statistically significant
BMI did not influence the accuracy in estimating uterine
size on bimanual exams
The objectives were met as shown by the above stated
results. For purposes of estimating uterine size prior to
hysterectomy bimanual examination highly correlates
with actual uterine size. These results do not support
pelvic ultrasound as a preferred method for purposes of
estimating uterine size
References

Cantuaria GH, Angioli R, Forst L, Duncan R, Penalver MA. Comparison of
bimanual examination with ultrasound examination before hysterectomy for uterine
leiomyoma. Obstet Gynecol 1998;92:109-12.

Flikinger L, D’Ablaing GD, Mishell, DR. Size and weight determinations of
nongravid enlarged uteri. Obstet Gynecol 1986;68: 855-8.

Harb T, Adam R. Predicting uterine weight before hysterectomy: Ultrasound
measurements versus clinical assessment. Am J Obstet Gynecol 2005;193: 2122-5.

Kung FT, Chang SY. The relationship between ultrasonic volume and actual weight
.
of pathologic uterus. Gynecol Obstet Invest 1998;42: 35-8