Objective—To compare the values of the urodynamic
parameters of the lower portion of the urinary
tract and vaginourethral measurements obtained during
the phases of the estrous cycle in dogs and determine
possible functional or anatomic modifications of
the lower portion of the urinary tract associated with
Animals—7 adult female Beagles.
Procedure—Urethral pressure profilometry, diuresis
cystometry, and vaginourethrography were performed
in each dog during proestrus; estrus; early,
mid, and late diestrus; and early and late anestrus. The
maximum urethral pressure (MUP), maximum urethral
closure pressure (MUCP), urethral functional and
anatomic profile lengths (UFPL and UAPL, respectively),
integrated pressure, threshold pressure,
threshold volume, compliance, urethral length, and
vaginal length and width were measured.
Results—For all measurements, significant interindividual
variation was detected. Integrated and threshold
pressures, APL, and each morphometric value significantly
increased from late anestrus to proestrus.
Compared with other phases, MUP, MUCP, and integrated
pressure values were significantly lower in
estrus and early diestrus; UAPL and UFPL values
were significantly lower in late diestrus. At each cycle
phase in old dogs, MUP, MUCP, threshold pressure,
and vaginal length and width were significantly lower
(except in proestrus for vaginal measurements) and
threshold volume and compliance values were significantly
higher, compared with middle-aged dogs.
Conclusions and Clinical Relevance—Urodynamic
and morphometric measurements of the lower portion
of the urogenital tract are affected by the changes
in hormonal balance that occur during the estrous
cycle. In sexually intact female dogs, estrous phase
determination is important for the interpretation of
urodynamic data. (Am J Vet Res 2005;66:1075–1083)
Objectives—To compare retrograde filling cystometry
at infusion rates of 5, 10, and 20 mL/min with
diuresis cystometry for determination of an appropriate
infusion rate and to confirm the reproducibility of
measurements obtained by urethral pressure profilometry
(UPP) and cystometry in female Beagles.
Animals—6 adult female Beagles.
Procedure—Successive UPP and cystometry were
performed by use of a water perfusion catheter on
dogs anesthetized with propofol. Dogs randomly
underwent each of the following at 1-week intervals:
retrograde filling cystometry at 5, 10, and 20 mL/min,
and diuresis cystometry. The maximum urethral pressure
and closure pressure, functional and anatomic
profile lengths, threshold pressure, threshold volume,
and compliance were measured.
Results—For each UPP variable, significant differences
were found among dogs, but no significant differences
were found in intra- or interstudy measurements
for individual dogs. For retrograde filling cystometry,
threshold pressure was not significantly different
between a 5 and 10 mL/min infusion rate.
Threshold pressure was significantly higher during
retrograde filling cystometry at 20 mL/min, compared
with 5 and 10 mL/min, and was associated with bladder
wall damages. Threshold pressure was significantly
lower during diuresis cystometry, compared
with retrograde filling cystometries. Threshold volume
and compliance were not significantly different
among retrograde filling cystometries but were significantly
higher during diuresis cystometry.
Conclusions and Clinical Relevance—Retrograde
filling cystometry at 20 mL/min leads to unacceptable
sudden increase in threshold bladder pressure.
Retrograde filling cystometry at 10 mL/min can be
recommended in a clinical setting, shortening the
anesthesia time. However, diuresis cystometry
approximates physiologic bladder filling most accurately.
(Am J Vet Res 2003;64:574–579)