Добавил:
Sekretar
kiopkiopkiop18@yandex.ru
t.me/Prokururor I Вовсе не секретарь, но почту проверяю
Опубликованный материал нарушает ваши авторские права? Сообщите нам.
Вуз:
Предмет:
Файл:Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_5786_Библиотеки_им_академика_М_И_Перельмана.pdf
✩ ✩✩✩✩✩✩✩✩✩✩✩
A
B
FHRP
uterus should be measured from a transverse view of the uterus, where it appears
to be at its widest. There is no consensus about how to measure uterine length,
i.e. whether to measure it as a straight line from the outer cervical os to the fundus uteri or whether to take separate measurements of the length of the cervix
and the uterine corpus and then to add the two, the results of the two measurement techniques being different if the uterus is flexed. Endometrial thickness is
measured from a sagittal view of the uterus, where it appears to be at its thickest.1
Ovarian volume (mL) can be calculated by measuring three orthogonal diameters
of the ovary and then using the formula: length (cm) × depth (cm) × width (cm)
× 0.5.
NORMAL ULTRASOUND MORPHOLOGY OF THE CERVIX UTERI
An ultrasound examination of the uterus should always start with examination
of the cervix. The cervical canal should be identified and followed towards the
corpus uteri so that it can be seen to join the endometrium. This examination
technique ensures that it is indeed the uterus and the endometrium that have
Ultrasound in obstetrics and gynaecology
been identified.
The myometrium of a normal cervix is homogeneous. In the late proliferative
phase of the menstrual cycle, clear fluid, corresponding to the ovulatory cervical
mucus, can be seen in the cervix. The finding of many and even large retention
cysts in the cervix is normal. Ultrasound images of a normal cervix are shown in
Figure 16.1.
NORMAL ULTRASOUND MORPHOLOGY OF THE UTERUS IN WOMEN OF FERTILE AGE
The myometrium of a normal uterus is homogeneous. The ultrasound morphology of the endometrium changes during the menstrual cycle.
of the menstrual cycle, the uterus is at its smallest and the endometrium is thin.
During the follicular phase, the uterus increases in size and the endometrium
becomes thicker and manifests a ‘triple-layer’ appearance. It is thought that the
central echogenic line represents direct contact of the anterior and posterior
286
Fig. 16.1 A normal cervix (A) at the time of ovulation containing fluid corresponding to
ovulatory cervical mucus and (B) containing two retention cysts.
2,3
In the beginning
✩✩✩✩✩✩✩✩✩✩✩ ✩
A
D
E
B
C
endometrial layers, and that the two outer hyperechogenic lines represent the
endometrial–myometrial junction. After ovulation the ‘triple-layer’ appearance
of the endometrium disappears and the endometrium becomes homogeneously
hyperechoic. Echo enhancement is often seen behind a secretory endometrium.
These endometrial changes are illustrated in Figure 16.2. On a transverse or longi-
tudinal section through a uterus, the outer layers of the myometrium may be seen
to contain small circular hypoechoic (black) spaces. These correspond to blood
vessels (see Fig. 16.2) and are often seen both in women of fertile age and in post-
menopausal women.
In a nulliparous woman, a normal uterus measures approximately 7 cm in
length, 3 cm in anterior–posterior diameter and 4 cm in width; in a parous
woman it measures approximately 8 cm in length, 4 cm in anterior–posterior
diameter and 4.5 cm in width. In a woman who has given birth to two or more
children, the uterus may even be slightly larger.4 Endometrial thickness changes
Normal gynaecological anatomy (uterus, tubes, ovaries)
Fig. 16.2 Endometrial ultrasound morphology changes during a normal menstrual cycle.
(A) On cycle days 2–4 the endometrium is thin and hyperechoic; ‘pencil-line’ appearance.
(B) In the late proliferative phase the endometrium becomes thicker and exhibits ‘triplelayer’ appearance. (C) In the secretory phase the endometrium is thick and homogeneously
hyperechogenic. (D) Echo enhancement (arrows) is often seen behind the secretory
endometrium. (E) Uterus with vessels in its periphery (arrows).
287
✩ ✩✩✩✩✩✩✩✩✩✩✩
throughout the menstrual cycle, the endometrium being at its thinnest at the
end of menstruation (3–5 mm). During the follicular phase it increases in thickness until ovulation when it is about 10 mm thick, and then it remains virtually
unchanged in thickness throughout the secretory phase.
5
NORMAL ULTRASOUND MORPHOLOGY OF THE OVARIES IN WOMEN OF FERTILE AGE
Ovarian ultrasound morphology also changes during the menstrual cycle.
the beginning of the menstrual cycle both ovaries usually contain 6–7 follicles of
<10 mm in diameter.6 The non-dominant ovary retains this appearance throughout the menstrual cycle.6 In the early follicular phase, it is not possible to determine which ovary is going to become the dominant one, i.e. the one carrying the
follicle destined to ovulate. The dominant ovary can usually be identified 9–6 days
(mean 7 days) before the LH surge, i.e. between cycle days 5 and 12 (mean cycle
day 8), the dominant ovary being the ovary carrying a follicle larger than any of the
other follicles and with a diameter of the largest follicle, >10 mm.6 The dominant
Ultrasound in obstetrics and gynaecology
follicle displays a linear growth rate of 1.4–2.2 mm (mean 1.7) per day.6 At the
time of the LH surge the leading follicle has a diameter of 18–22 mm.6 After ovulation the follicle becomes a corpus luteum. The corpus luteum is usually smaller
than the dominant follicle, its wall is thicker, and with high-resolution ultrasound
systems it is possible to see the crenellated appearance of its wall. Bleeding into
the corpus luteum explains the presence of echoes in the corpus luteum at ultrasound examination.3 The corpus luteum is well vascularized and therefore it is surrounded by a ‘colour ring’ on colour or power Doppler ultrasound examination
(see also below). On the third day of menstruation the corpus luteum of the previous cycle is no longer distinguishable, not even using colour Doppler ultrasound.9
Changes in the ultrasound appearance of the ovaries during a normal menstrual
cycle are illustrated in Figure 16.3.
Ovarian size changes during the menstrual cycle. The volume of the nondominant ovary is approximately 7–8 mL and remains unchanged throughout
the menstrual cycle, while the volume of the dominant ovary increases from
7–8 mL in the early follicular phase to approximately 20 mL on the day before
ovulation. After ovulation, it decreases slightly and is approximately 15 mL in
the luteal phase.
8
3,6
In
7,8
288
NORMAL ULTRASOUND MORPHOLOGY OF THE UTERUS AND OVARIES IN POSTMENOPAUSAL WOMEN
The uterus and ovaries are smaller in postmenopausal women than in women of
fertile age.4 A normal uterus in a woman who is more than 5 years postmenopausal may measure 5–6 cm in length, 2.5 cm in anterior–posterior diameter and
3 cm in width, and a normal ovary may have a volume of 1–4 mL.
metrium has uniform ultrasound morphology because there are no cyclical hormonal changes. It is thin (usually no more than 5 mm thick) and hyperechoic.
4,10
The endo-
4,10
✩✩✩✩✩✩✩✩✩✩✩ ✩
A
D
E
B
C
Normal gynaecological anatomy (uterus, tubes, ovaries)
Fig. 16.3 Changes in ovarian ultrasound morphology during a normal menstrual cycle.
(A) Normal ovary in the early follicular phase; at this stage both ovaries look similar, they
usually contain 6–7 follicles <10 mm in diameter, and the non-dominant ovary retains
this appearance throughout the menstrual cycle. (B) A normal dominant ovary with one
follicle larger than any of the other follicles and with a diameter of >10 mm. (C) A normal
dominant ovary in the luteal phase, where the corpus luteum has a crenellated appearance
and echogenic contents. (D) A normal dominant ovary in the luteal phase, where the corpus
luteum has anechoic contents. (E) A normal dominant ovary in the luteal phase with a
haemorrhagic corpus luteum.
Calcified blood vessels in the periphery of the myometrium are common in
postmenopausal women and are seen as bright echoes in the periphery of the
uterus (see Fig. 16.3).
In a postmenopausal woman the ovaries contain no follicles but one or more
inclusion cysts up to 10 mm in diameter are common and normal ultrasound
findings in postmenopausal women.
pausal uteri and ovaries are shown in Figures 16.4 and 16.5.
10,11
Ultrasound images of normal postmeno-
289
✩ ✩✩✩✩✩✩✩✩✩✩✩
A
B
A
B
C
Ultrasound in obstetrics and gynaecology
Fig. 16.4 Ultrasound images of a normal postmenopausal uterus. (A) Longitudinal view; the
endometrium is thin and hyperechogenic. (B) Transverse view. (C) Calcifications of vessels
appearing as echogenic spots in the periphery of a normal postmenopausal uterus.
Fig. 16.5 Ultrasound images of normal postmenopausal ovaries. (A) Small ovary without
visible follicles. (B) Ovary with a follicle-like cystic structure, in all likelihood an inclusion cyst.
NORMAL ULTRASOUND MORPHOLOGY OF THE UTERUS AND OVARIES IN MENOPAUSAL TRANSITION
Menopausal transition starts with the beginning of the first menstrual irregularity
and ends with the final menstrual period (menopause). The menopausal transition period precedes the final menses by 2–8 years. In one of our own studies24 we
examined women longitudinally from 2 years before to 2 years after their menopause. As early as 2 years before menopause, the ovaries were smaller (largest
290
ovary approximately 6 mL) than in normo-ovulatory women of fertile age where
✩✩✩✩✩✩✩✩✩✩✩ ✩
A
B
the volume of the non-dominant ovary is about 8 mL (see above).8 Moreover, in
the women in menopausal transition the ovaries usually contained only one or two
follicles versus the reported six to seven in women of reproductive age.6 The greyscale ultrasound findings in women in menopausal transition were clearly different
from those in women of fertile age, not only because the number of follicles was
much lower but also because in 70% of the examinations performed during menopausal transition, it was impossible to determine the phase of the menstrual cycle,
the endometrium not manifesting the features typical of proliferation or secretion
and there being no dominant follicle or corpus luteum. This is in agreement with
the findings of Landgren et al, who reported that 62% of menstrual cycles examined during the last 10 years before menopause were anovulatory.
12
NORMAL UTERINE AND OVARIAN VASCULARIZATION AS ASSESSED BY DOPPLER ULTRASOUND TECHNIQUE
Uterine and ovarian vascularization can be studied non-invasively using twodimensional or three-dimensional Doppler ultrasound technique. Both uterine
and ovarian vascularization change throughout the menstrual cycle.
indirect evidence that the uterus and endometrium are better perfused in the late
follicular and luteal phase than in the early follicular phase. Blood flow velocities
are higher and the pulsatility index is lower in the main uterine arteries and subendometrial arteries, and blood flow indices in endometrial and subendometrial volumes obtained at three-dimensional power Doppler ultrasound examination are
higher in the late follicular and luteal phase than in the early follicular phase.
The same is true of the dominant ovary,
7,8
where changes in vascularization are
obvious to the naked eye: the ovary bearing the dominant follicle (and especially
the wall of the dominant follicle) becomes successively more intensely coloured
on colour Doppler ultrasound examination from 1 to 2 days before ovulation, and
the ovary harbouring the corpus luteum is more intensely coloured than the same
ovary before ovulation and than the contralateral ovary.7 These changes are illustrated in Figure 16.6. Even though a corpus luteum can usually be distinguished
7–9,13
There is
7,13
Normal gynaecological anatomy (uterus, tubes, ovaries)
Fig. 16.6 Ultrasound images illustrating the difference in vascularization between the
dominant follicle and the corpus luteum. (A) Power Doppler image of the dominant follicle;
only a thin line of colour surrounds a small part of the follicle. (B) Power Doppler image of
the corpus luteum; a thick line of colour surrounds a large part of the corpus luteum.
291
✩ ✩✩✩✩✩✩✩✩✩✩✩
from a follicle on the basis of the grey-scale ultrasound image alone (thicker wall,
more irregular wall, crenellated wall, echogenic contents), the thick and intense
colour ring surrounding a corpus luteum may help confirm its presence.
THE TUBES
The interstitial part of the tube can be seen on a transverse section through the
uterus. It is important to identify this part of the tube at hystero-contrast salpingosonography (see below). The more distal parts of a normal tube cannot be seen
at ultrasound examination, unless the tube is floating freely in fluid in the pouch
of Douglas or in ascites (Fig. 16.7).
THE POUCH OF DOUGLAS
In women of fertile age, fluid is almost always seen in the pouch of Douglas, at
least in the late follicular phase and in the early secretory phase of the menstrual
cycle3 (Fig. 16.8). In the early secretory phase, the pouch of Douglas normally
Ultrasound in obstetrics and gynaecology
contains 15–25 mL fluid.3 It is not possible to give an exact cut-off in millimetres
of a normal amount of pelvic fluid in a woman of fertile age, but fluid outside
the pouch of Douglas, e.g. in the space between the uterus and the bladder, is
extremely unusual and should be regarded as abnormal.
An ultrasound finding of fluid in the pouch of Douglas in a postmenopausal
woman is not normal. Follow-up is needed to exclude disease explaining the
fluid.
292
Fig. 16.7 Ultrasound image of a normal tube floating in free fluid.
Fig. 16.8 Normal amount of fluid in the pouch of Douglas in a woman of fertile age.
✩✩✩✩✩✩✩✩✩✩✩ ✩
HYDROSONOGRAPHY
Hydrosonography, i.e. infusion of sterile saline into the uterine cavity during
transvaginal scanning, makes it possible to detect focal lesions (e.g. endometrial
polyps or submucuous myomas) in the uterine cavity.14 Hydrosonography is carried out by inserting a thin sterile plastic catheter (e.g. a baby feeding tube or an
insemination catheter) connected to a sterile syringe containing sterile saline into
the uterine cavity through the cervical canal. A balloon catheter is not needed;
it is expensive and inflation of the balloon causes the woman unnecessary pain.
Insertion of the catheter is usually easy in women of fertile age but may be difficult in postmenopausal women, who often have a stenotic cervix. In these
women it may be necessary to use both a tenaculum and a small uterine sound
before the catheter can pass into the uterus. When the catheter is in place, the
vaginal transducer is introduced into the vagina and the uterine cavity is scanned
while saline is being infused into the cavity. Sometimes only a few millilitres of
saline is needed to expand the cavity. If there is backflow, more than 20 mL may
be required. One should strictly avoid introducing air into the uterine cavity,
because air obscures the view. Some have used hydroxyethylcellulose gel containing anaesthetic and antiseptic agents instead of saline, the alleged advantages
being less fluid leakage and less pain.
A normal uterine cavity in the follicular phase of the menstrual cycle or in
a postmenopausal woman is smooth and contains no focal lesions. Possibly, a
thick secretory endometrium or an otherwise hormonally influenced endometrium may be folded, and such folds could potentially be confused with focal
lesions. However, because of the possibility of the presence of an early pregnancy,
hydrosonography should not be carried out in the secretory phase of the menstrual cycle. To the best of our knowledge, the normal appearance of a secretory
endometrium at hydrosonography is not known. Hydrosonography images are
shown in Figure 16.9.
We have found no scientific studies that have examined whether or not cleansing
of the vagina or prophylactic antibiotics should be recommended before hydrosonography. In our ultrasound unit, we do not clean the vagina before hydrosonography
and we do not give prophylactic antibiotics.
15
Normal gynaecological anatomy (uterus, tubes, ovaries)
HYSTERO-CONTRAST SALPINGOSONOGRAPHY (HyCoSy)
Traditionally, tubal patency has been assessed by hysterosalpingography. This
examination can be replaced by hystero-contrast salpingosonography (HyCoSy),
where the flow of a contrast medium from the uterine cavity into the fallopian
tubes is observed using ultrasound technique.16 The late preovulatory phase of
the menstrual cycle (days 8–12) is the optimal time to perform this examination.
It should not be carried out in the secretory phase because of the possibility of
the presence of an early pregnancy.
HyCoSy is usually immediately preceded by hydrosonography to assess the
uterine cavity (see above) and is performed by inserting a sterile balloon catheter
293
✩ ✩✩✩✩✩✩✩✩✩✩✩
A
C
D
B
Ultrasound in obstetrics and gynaecology
Fig. 16.9 Normal ultrasound findings at hydrosonography, i.e. the endometrium outlining
the cavity is smooth and there are no focal lesions. (A) Transverse view of the uterus from a
woman in the proliferative phase of the menstrual cycle. (B) Transverse view of the uterus
from a woman in the secretory phase of the menstrual cycle. Hydrosonography should
not be carried out in the secretory phase of the menstrual cycle but this examination was
performed under exceptional circumstances. The endometrium is thick and slightly folded.
(C) Longitudinal view of the uterus in a postmenopausal woman. (D) Transverse view of the
uterus from a woman with a thick and folded hormonally influenced endometrium; the folds
could potentially be confused with focal lesions.
connected to a sterile syringe containing a sterile contrast medium into the uterine
cavity through the cervical canal. There are dedicated commercial contrast media
but air in saline can also be used.
17,18
A balloon catheter, or some other catheter
that prevents backflow through the cervix, is needed to force the contrast medium
into the tubes. The balloon can be inflated either in the cervix or in the uterine
cavity. Both procedures may be painful. When the catheter with its inflated balloon is in place, the vaginal transducer is introduced into the vagina and the uterine cavity is scanned while the contrast medium is slowly being injected. When
starting the contrast infusion, it is good to have a sagittal view of the uterus on the
screen. When the contrast is seen to arrive at the upper part of the uterine cavity,
one changes to a transverse view of the fundus uteri with the interstitial part of
one of the tubes in view, so that the passage of contrast medium through the interstitial part of the tube can be seen. By manipulating the probe, the contrast can be
294
followed from the interstitial part of the tube to its fimbrial end, where free spill
✩✩✩✩✩✩✩✩✩✩✩ ✩
A
B
C
E
F
G
D
can be observed. Observing free spill may be difficult, because the contrast agent
has the same echogenicity as the surrounding bowel. On the other hand, the proximal end of the tube filled with running contrast medium is almost always visible.
If one can observe moving contrast in the interstitial part of the tube for 10 seconds, and if no hydrosalpinx is seen, the fallopian tube is almost certainly patent,
even if free spill of contrast is not clearly seen.
19
It is only possible to assess the patency of one tube at a time. If at least one
tube is patent, there should be free contrast in the pouch of Douglas at the end
of the procedure. Ultrasound images from a HyCoSy procedure are shown in
Figure 16.10.
We have found no scientific studies that have examined whether or not cleansing
of the vagina or prophylactic antibiotics should be recommended before HyCoSy.
A Cochrane meta-analysis is being planned (‘Prophylactic antibiotics for transcervical intrauterine procedures’, J Thinkhamrop, M Laopaiboon, P Lumbiganon; ww w.
cochrane.org/) that might shed light on this issue in the future. In our unit we clean
the vagina with chlorhexidine 2 mg/mL and we do use prophylactic antibiotics.
We also give prophylactic painkillers 1 hour before the procedure to reduce pain.
Normal gynaecological anatomy (uterus, tubes, ovaries)
Fig. 16.10 Ultrasound images obtained during hystero contrast salpingosonography
(HyCoSy). (A) The contrast is seen to approach the fundus uteri on a sagittal view of the
uterus. (B) The contrast is seen to have entered the interstitial part of the right tube on a
transverse section through the uterus. (C) The contrast has entered the interstitial part of
both tubes. (D) Contrast in the right tube. (E) Contrast in the left tube. (F) Free contrast
in the pouch of Douglas; a normal result requires quick passage of contrast through the
interstitial part of the tube during at least 10 seconds and confirmation of contrast spreading
freely around the ovaries. (G) No passage of contrast into the free part of the tube, only
the interstitial part is filled with contrast. This is abnormal and suggests a blocked tube;
alternatively, tubal spasm could explain the finding.
295