College of Medical Sciences, Nova Southeastern University, Ft
Lauderdale, Florida 33328, USA. mayrovit@nova.edu
Assessing
changes in upper extremity limb volume during lymphedema therapy is
important for determining treatment efficacy and documenting outcomes.
Although arm volumes may be determined by tape measure, the suitability
of circumference measurements to estimate hand volumes is questionable
because of the deviation in circularity of hand shape. Our aim was to
develop an alternative measurement procedure and algorithm for routine
use to estimate hand volumes. A caliper was used to measure hand width
and depth in 33 subjects (66 hands) and volumes (VE) were calculated
using an elliptical frustum model. Using regression analysis and limits
of agreement (LOA), VE was compared to volumes determined by water
displacement (VW), to volumes calculated from tape-measure determined
circumferences (VC), and to a trapezoidal model (VT). VW and VE (mean
+/- SD) were similar (363 +/- 98 vs. 362 +/-100 ml) and highly
correlated; VE = 1.01VW -3.1 ml, r=0.986, p<0.001, with LOA of +/-
33.5 ml and +/- 9.9 %. In contrast, VC (480 +/- 138 ml) and VT (432 +/-
122 ml) significantly overestimated volume (p<0.0001). These results
indicate that the elliptical algorithm can be a useful alternative to
water displacement when hand volumes are needed and the water
displacement method is contra-indicated, impractical to implement, too
time consuming or not available.
Department
of Physiology, College of Medical Sciences, Nova Southeastern
University, Ft. Lauderdale, Florida 33328, USA. mayrovit@nova.edu
Assessing
lower extremity limb volume and its change during and after lymphedema
therapy is important for determining treatment efficacy and documenting
outcomes. Although leg volumes may be determined by tape measure and
other methods, there is no metric method to routinely assess foot
volumes. Exclusion of foot volumes can under- or overestimate
therapeutic progress. Our aim was to develop and test a metric
measurement procedure and algorithm for practicing therapists to use to
estimate foot volumes. The method uses a caliper and ruler to measure
foot dimensions at standardized locations and calculates foot volume
(VM) by a mathematical algorithm. VM was compared to volumes measured
by water displacement (Vw) in 30 subjects (60 feet) using regression
analysis and limits of agreement (LOA). Vw and VM (mean +/- sd) were
similar 857 +/- 150 ml vs. 859 +/- 154 ml, and were highly correlated
VM = 1.00Vw + 1.67 ml, r = 0.965, p < 0.001. The LOA for absolute
volume differences and percentages were respectively +/- 79.6 ml and
+/- 9.28 %. These results indicate that this metric method can be a
useful alternative to water displacement when foot volumes are needed,
but the water displacement method is contraindicated, impractical to
implement, too time consuming or is not available.
Upper-extremity
volume measurements in women with lymphedema: a comparison of
measurements obtained via water displacement with geometrically
determined volume.
Department
of Physical Therapy and Human Movement Sciences, The Feinberg School of
Medicine, Northwestern University, 645 N Michigan Ave, Suite 1100,
Chicago, IL 60611, USA. t-sander@northwestern.edu
BACKGROUND AND
PURPOSE: Upper-extremity (UE) swelling following breast cancer
treatment is a frequent manifestation of lymphedema. In order to
document outcomes from lymphedema treatments, reliable, valid, and
practical measurements of UE swelling are necessary. The purpose of
this study was to compare geometric methods of determining UE volumes
with water displacement methods. SUBJECTS: The edematous hand, forearm,
and upper arm of 50 women with UE swelling secondary to lymphedema were
measured. METHODS: Upper-extremity volumes were determined by water
displacement using arm and hand volumeters. Displaced water was weighed
to determine volume. Circumferential girth measurements were taken.
Width and depth measurements of the hand were taken with a
tension-controlled caliper. Geometric volume formulas for a cylinder,
frustum, rectangular solid, and trapezoidal solid were used to
calculate volumes of the arm and hand at different measurement
intervals. RESULTS: Intraclass correlation coefficients [2,1] for
interrater and intrarater reliability of all water and geometric
measurements of the arm and hand were.91 to.99 and.92 to.99,
respectively. Water displacement correlated with geometric measurements
in the arm (r=.97-.98) and in the hand (r=.81-.91). The limits of
agreement (LOA) indicated that water and geometric measurements of arm
volume differed by 479 to 655 mL. Scatterplots of the LOA data
indicated in that geometric volumes were either larger or smaller than
water volumes. The smallest standard error of measurement for the arm
measurements was for the 6-cm frustum method at 115 mL; for the hand
measurements, the smallest standard error of measurement was for the
frustum method at 16 mL. DISCUSSION AND CONCLUSION: Volume of an
edematous UE calculated by geometric formulas correlated strongly with
volume determined by water displacement. Although strongly correlated,
the measurements obtained by the 2 methods did not agree.
Concurrent
validity of upper-extremity volume estimates: comparison of calculated
volume derived from girth measurements and water displacement volume.
Department
of Physical Therapy, Division of Health Sciences, School of Medicine,
University of South Dakota, 414 E Clark St, Vermillion 57069, USA.
jkarges@usd.edu
BACKGROUND AND PURPOSE: The volume of all limbs
can be determined by water displacement methods or calculations derived
from girth measurements. The purpose of this study was to determine the
concurrent validity of calculated volume and water displacement volume
measurements. SUBJECTS: Both upper extremities of 14 women with
lymphedema were measured. METHODS: Volumetric measurements were taken
with a volumeter, and circumferential measurements were taken with a
tape measure. Calculated volume was determined by summing segment
volumes derived from the truncated cone formula. Pearson product moment
correlations, paired t tests, and linear regression tests were used to
assess relative association and absolute differences between calculated
and actual volumes. RESULTS: The correlation coefficient for calculated
volume versus upper extremity minus fingers (UE-F) water displacement
volume was.99. Paired t tests showed differences between calculated
volume and UE-F water displacement volume (t=-3.88, mean
difference=-95.62 mL), and the linear regression slope was 0.83 with an
intercept of 255.28 mL. DISCUSSION AND CONCLUSION: Calculated volume
measurements were highly associated with measurements based on water
displacement; therefore, clinicians should feel confident in using
either calculated volume or water displacement volume. The differences,
however, indicated that the measures were not interchangeable. Thus,
clinicians should not mix or substitute measurement methods with a
single patient or in a single study.
School of Population Health, Faculty of Health Sciences, University of
Queensland, Herston, Queensland, Australia.
BACKGROUND
AND PURPOSE: Arm lymphedema following breast cancer surgery is a
continuing problem. In this study, we assessed the reliability and
validity of circumferential measurements and water displacement for
measuring upper-limb volume. SUBJECTS: Participants included subjects
who had had breast cancer surgery, including axillary dissection--19
with and 22 without a diagnosis of arm lymphedema--and 25 control
subjects. METHODS: Two raters measured each subject by using
circumferential tape measurements at specified distances from the
fingertips and in relation to anatomic landmarks and by using water
displacement. Interrater reliability was calculated by analysis of
variance and multilevel modeling. Volumes from circumferential
measurements were compared with those from water displacement by use of
means and correlation coefficients, respectively. The standard error of
measurement, minimum detectable change (MDC), and limits of agreement
(LOA) for volumes also were calculated. RESULTS: Arm volumes obtained
with these methods had high reliability. Compared with volumes from
water displacement, volumes from circumferential measurements had high
validity, although these volumes were slightly larger. Expected
differences between subjects with and without clinical lymphedema
following breast cancer were found. The MDC of volumes or the error
associated with a single measure for data based on anatomic landmarks
was lower than that based on distance from fingertips. The mean LOA
with water displacement were lower for data based on anatomic landmarks
than for data based on distance from fingertips. DISCUSSION AND
CONCLUSION: Volumes calculated from anatomic landmarks are reliable,
valid, and more accurate than those obtained from circumferential
measurements based on distance from fingertips.
Direct and indirect methods for the
quantification of leg volume: comparison between water displacement
volumetry, the disk model method and the frustum sign model method,
using the correlation coefficient and the limits of agreement.
Department of General Surgery/Traumatology, University Hospital
Rotterdam Dijkzig, The Netherlands.
Volume
changes can be measured either directly by water-displacement volumetry
or by various indirect methods in which calculation of the volume is
based on circumference measurements. The aim of the present study was
to determine the most appropriate indirect method for lower leg volume
calculation using water displacement volumetry as a 'golden standard'.
For 20 male volunteers, age range: 20-35 years, the volume of both
lower legs was determined directly by water-displacement volumetry, and
indirectly by the frustum sign model method and the disc model method.
Calculation of the correlation coefficient and the limits of agreement
showed that water-displacement volumetry and the disc model method are
interchangeable (r = +0.99, mean +/- 2s = -45 +/- 78 ml), whereas this
does not hold for the frustum sign model (r = +0.93, mean +/- 2s = 521
+/- 238 ml). In the clinical situation volume measurement can be
valuable for monitoring of the severity of oedema or haematoma
occurrence after surgery or severe trauma. This non-invasive diagnostic
aid may be a valuable adjuvant means of diagnosis for several volume
dependent disorders of the extremities.
G.F. Strong Centre, British Columbia Rehabilitation Society, Vancouver,
Canada.
Limb
edema is a common problem in both rehabilitation and acute care
settings. In the past, attempts to determine an optimal management
strategy for limb edema have been limited by the lack of accurate,
noninvasive, rapid, clinical tools for quantifying limb volumes. The
water displacement method is slow and difficult to use in the clinical
setting. Furthermore, water displacement requires that the limb be in a
dependent position. The tape measure method is unreliable because it is
difficult to position the tape measure on a swollen limb. The
development and evaluation of a new tool called the computerized limb
volume measurement system (CLEMS) is described. The shape and volume of
a limb or limb segment can be rapidly measured by CLEMS, independent of
limb position. The limb volumes generated by CLEMS were compared to
volumes determined by water displacement and by a tape measure. Volumes
of eighteen legs (plaster, nonedematous and edematous) were measured
using CLEMS, water displacement, and the tape measure. In all cases,
the CLEMS and water displacement methods showed close agreement. CLEMS
was found to be a reliable and valid new method of determining limb
volume; whereas, the tape measure method was found to be invalid. This
new tool allows clinicians to measure the efficacy of different
treatment strategies in the management of limb edema.
Department
of Physiology, College of Medical Sciences, Nova Southeastern
University, Fort Lauderdale, Florida, USA. mayrovit@Comcast.net
Limb
volumes, as would be estimated by the widely used right circular
truncated cone model (right circular frustum), were analytically
compared to volume estimates that would be obtained if limbs were
represented by an elliptical cross section. A general expression for
the ratio of circular to elliptical limb segmental volumes was
developed in terms of the ratio of minimum to maximum limb radial
dimensions. Analytical results showed that in general the elliptical
representation resulted in smaller calculated limb volumes, with the
difference increasing as the ratio of minimum to maximum limb dimension
became smaller. However, differences in estimated limb volume between
circular and elliptic representations were less than 5% if the minimum
to maximum limb dimensions at measured circumference sites were greater
than 0.64. It is concluded that although limbs deviate from
circularity, the added work of determining minimum and maximum
dimensions for each circumference measured, as is needed to employ
elliptical models, is warranted only for extreme differences in limb
radial dimensions or possibly for research purposes.
Department of Rehabilitation, University Hospital Groningen, The
Netherlands.
We
investigated a method of indirect volume measurement that utilized
surface measurements and a simplified formula derived from the formula
for a frustum (Sitzia's method) to determine limb volumes in patients
with breast cancer-related lymphedema of the upper extremity. Repeated
measurements of upper-extremity limb volume were obtained by two
observers on both upper extremities of 30 women with unilateral
lymphedema. Volume was calculated using a simplified formula and
compared with water displacement method as a gold standard. Indirect
volume determination using Sitzia's method is comparable with the water
displacement method, has comparable intra- and interobserver
reliabilities, and can be used for diagnosis and follow up measurements
of lymphedema. Indirect volume determination using surface measurements
at 8 cm intervals is only suitable for follow up measurements. The
methods should not be used interchangeably.
Department of Surgery, Royal Postgraduate Medical School, Hammersmith
Hospital, London, U.K.
OBJECTIVES:
The aim of the study was to compare a novel infrared optoelectronic
system (Perometer) of limb volume measurement with water displacement
and two indirect measurement techniques. DESIGN: A prospective
experimental study. METHODS: In 10 healthy male volunteers (20 limbs)
we compared limb volume measurements obtained by water displacement,
infrared perometry, the disc model method and the frustrum method. In a
further 17 patients with swollen limbs due to lymphatic (9 limbs) or
venous (11 limbs) disease, perometry was compared to the disc model
method and the frustrum method only. RESULTS: In normal limbs, mean +/-
S.D. limb volume using water displacement was 1802 +/- 268 ml.
Perometer values agreed almost exactly (1809 +/- 262 ml, r = 0.97,
variation +/- 7% by limits of agreement) but both the disc (1923 +/-
306 ml, r = 0.90, variation +/- 14%) and frustrum (1905 +/- 372 ml, r =
0.72, variation +/- 28%) methods significantly overestimated limb
volumes (p < 0.05 (ANOVA, Fisher's Least Significant Difference)).
In diseased limbs perometer, disc method and frustrum method results
were 2415 +/- 995 ml, 2494 +/- 969 ml, and 2413 +/- 870 ml representing
variation of +/- 17% and +/- 23% for disc method and frustrum method
respectively compared to perometry. CONCLUSIONS: Perometry is a novel,
extremely accurate and easy method for assessing limb volume. It
provides more accurate results than traditional indirect measurement of
limb volume and potentially is a very useful clinical and research tool.
School of Rehabilitation Sciences, Faculty of Medicine, University of
British Columbia, Vancouver, Canada.
OBJECTIVE:
To determine if 2 methods of calculating upper extremity volume (using
arm circumferences) can substitute for water displacement volumetry.
DESIGN: Interrater and test-retest reliability and limits of agreement
for volume measures. SETTING: University. PARTICIPANTS: Twenty-five
women at risk for lymphedema who had undergone axillary lymph node
dissection surgery for breast cancer. INTERVENTIONS: Circumference and
volume measurements of both upper extremities were taken by 2 physical
therapists at an initial visit and by 1 of the therapists 1 week later.
MAIN OUTCOME MEASURES: Intraclass correlation coefficients (ICCs) were
calculated to analyze measurement reliability. Pearson's product-moment
correlation coefficient (r) was used to evaluate the relationship
between volumetry and calculated truncated cone volumes. Limits of
agreement were calculated to determine the level of agreement between
the 2 measurement methods. RESULTS: Interrater and test-retest
reliability ICCs for circumferential and volumetric data were .99 and
.99, respectively. Pearson's r values were .93 and .97 for the single
truncated cone and the summed truncated cone volume calculations,
respectively. Limits of agreement (mean +/- 2 standard deviations) were
-52 +/- 334mL and -40 +/- 234mL, respectively, between volumetry and
the single truncated cone and summed truncated cone calculations.
CONCLUSIONS: Calculated and volumetric measurements in this population
are both reliable and closely related, but do not agree with each
another, and thus should not be used interchangeably. Copyright 2001 by
the American Congress of Rehabilitation Medicine and the American
Academy of Physical Medicine and Rehabilitation
Department
of Dermatology, Phlebology and Lymphology, Hospital Nij Smellinghe,
Compagnonsplein 1, 9202, NN Drachten, The Netherlands,
r.j.damstra@nijsmellinghe.nl.
BACKGROUND: No consensus exists
with respect to a commonly accepted and standardized method for
measuring arm volumes in patients with lymphedema. Knowing the exact
volume in (potential) lymphedemic arms and comparing this volume with
healthy arms is important to detect the first signs of lymphedema and
to study the effects of treatment. METHODS: A new apparatus, based upon
the principle of measuring shortness of water, was developed to measure
arm volumes. This measuring-method, inverse water volumetry, was
prospectively validated in patients, suffering from lymphedema after
complete or partial mastectomy for primary breast cancer. Healthy and
lymphedemic arm were measured 3 times: twice by nurse A (A1 and A2) and
once by nurse B (B). Subsequently, these differences in volumes were
compared with differences in volumes obtained by the Herpertz method,
which is based upon circumferential measurement. RESULTS: In every
patient at every occasion volume of the lymphedemic arm was bigger than
the corresponding volume of the control arm. Mean volumes of healthy
arms were 3958(A1), 3966(A2) and 3961(B) ml respectively. Mean volumes
of lymphedemic arms were 4721(A1), 4752(A2) and 4773(B) ml
respectively, volume B being significantly different from volume A1.
Volume difference of edemic arms minus control arms was not significant
between measurements (A1 vs. A2 and A1 vs. B, respectively), while this
difference was significant (A1 vs. B) using the Herpertz method.
CONCLUSION: Inverse water volumetry is an easy measuring device with a
high inter- and intra-observer agreement. The small but significant
volume increase of lymphedemic arms in time compared to the constant
volumes of control arms is as well indicative for the accuracy of the
method as for the volume of lymphedemic arms to increase when no
therapeutic garment is carried.
PMID: 16752072 [PubMed - as supplied by publisher]
Vector Control Research Centre (Indian Council of Medical Research),
Indira Nagar, Pondicherry.
To
evaluate the impact of therapy and monitor the progression of filarial
lymphedema, it is necessary to measure accurately the changes in limb
edema volume. In this communication, we report the reliability of
circumference measurements for recording volume changes. The
measurements included the distal parts of limbs important for filarial
lymphedema. In a series of 100 patients with unilateral lower limb
lymphedema, both water displacement and circumference measurements were
done. The results showed a significant correlation (r = 0.91; P =
0.0000) between the actual volume and that estimated by circumference
measurement. Not only could volume of edema be calculated by
circumference measurements, but the simple measurement of average
circumference difference between the affected and normal limb
accurately reflected the volume of actual edema.
Henry Thomas Laboratory (Microcirculation Research), University of
Adelaide, South Australia.
Correlation
was very good between 1,500 simultaneous measurements of peripheral
lymphoedema (arms and legs) by water displacement and by calculating
volumes from circumferences, but in the legs "circumferences" gave only
half the absolute amount of oedema when compared with "water
displacement." For 150 arms, however, each method provided almost
identical values for oedema. Arms when oedematous are fairly uniformly
swollen; legs, on the other hand, are typically more oedematous
distally. Circumference measurements accordingly include portions of
nearly normal (i.e., minimally or nonoedematous) leg; water
displacement by contrast measures only the oedematous, distal region.
When only the circumferences of the lower legs were taken into
consideration, the amount of oedema as measured by water displacement
were almost identical. Nonetheless, measuring the proximal, more
normal, or nonoedematous regions of the leg is critical for assessing
treatment by physical methods (e.g., complex physical therapy). The
various equations representing oedema can be greatly affected by errors
in the initial, final or normal measured volumes. Relative errors
differ as these variables alter. Many of the equations are non-linear,
i.e., small alterations in one variable may produce widely differing
results depending on the other variables. Problems in the use of an
abnormal contralateral or "normal" limb as a reference point are
discussed. The best equation to use in bilateral oedema is "Difference
in Volume/Initial Volume"; in unilateral oedema the best equation is
"Difference in Oedema/Normal". "Change in Oedema" i.e., "Difference in
Oedema/Initial Oedema" is best derived from the Means of other
equations.
