Anatomy of Ovaries & Pelvic
surgery : what we have to remember ?? Point
1:- Shape & location of ovaries:--Anatomy of Ovaries & Pelvic surgery :-All pelvic Surgeon should remember that in most diseases ovaries are usually
but nor always glued to pelvis along
with “ureter in the back”
which is a bit puckered too. –We know
that the normal ovary is ellipsoid in shape and is variable in both location and orientation depending upon the age and parity of the patient as well as the
degree of bladder distention,
endometriotic adhesions , pelvic
adhesive diseases, Kochs and previous pelvic
surgeries
In the nulliparous adult female the
ovaries are situated in
the ovarian fossa (no surgery for leaking CL have been done , but may be
adherent if she had had App open in school age) which is adjacent to the lateral pelvic side wall
and is bounded by the obliterated umbilical artery anteriorly.
Does mean
ovarian volume changes in
different phases of menst cycle?? Ovarian volume is calculated by measuring the ovary in
three dimensions on two
orthogonal planes and using the formula for the prolate ellipse .
Ovarian size depends upon age menstrual cycle. In premenopausal
women the mean ovarian volume
is 9.8 ml with the highest volumes
found in the preovulatory phase
and th lowest volumes in the luteal phase. Normal ovarian volume
decreases after the age of 30 years. In
one large study ovarian volumes decreases after the age of 30 years. In one large study mean
ovarian volume significantly
decreased in each decade up to
age 60 years measuring
6.6 ml in women under 30 years of age 6.1 ml in women 30 to 39 years old 4.8 ml at ages
40 to 49 years 2.6 ml
over age 70 years. The authors found
a statistically significant increased
ovarian size in tall women but
no relationship to weight
Despite the small size of the
postmenopausal ovary the majority are detectable by TVS.
The normal
ovary in women of reproductive age has a variable appearance over the course
of the menstrual cycle. Developing and immature follicles can
be seen throughout the
entire menstrual cycle and appear
as anechoic unilocular
sharply marginated cysts measuring from 2 to 9
mm by days 8 to 12 of the menstrual cycle one or more dominant follicles will grow
to a diameter of
approximately 20 to 25 mm and then rupture at ovulation releasing the oocyte Up to 80% of patients have a second
non dominant follicle that becomes almost as a large as the dominant
follicle. The preovulatory dominant
follicles . The preovulatory dominant follicle may have a slightly complex
appearance with the oocyte and its supporting structures appearing as a ring
like structure within the follicle following
ovulation the corpus luteum
evolves from the remnant of the
mature follicles through
a process of cellular
hypertrophy and increased vascularization of the cyst wall. Therefore a corpus
luteum is typically visible
in the secretory phase of the menstrual cycle and in the
first few weeks of early pregnancy .
On
sonographic imaging, the corpus
luteum typically has a relatively thick homogenously echogenic wall the
inner margin of which may be
slightly irregular with a crenulated appearance . on color Doppler
the wall of the corpus luteum often
demonstrates a circumferential ring of arterial flow with a low
resistance spectral Doppler waveform. Internal echoes are common
reflecting variable amounts of internal hemorrhage that occurred at
the time of ovulation and occasionally
a corpus luteum may be
filled with homogenous low level echoes mimicking a solid mass. However there
is usually evidence of enhanced
through transmission because of the fluid
content and there will be no central
vascularity . Typically the corpus
lute is under 3.0 cm in maximal
dimension but rarely it may become larger. If pregnancy does not occur the corpus
luteum gradually involutes and
atrophies to become the corpus
albicans which is
typically not sonographically identifiable. Small
echogenic foci measuring 1 to 3
mm may be noted in the periphery of otherwise normal appearing ovaries
in approximately half of women
undergoing TVS particularly in the perimenopausal age
group . These foci often demonstrate ring down artifact and are a benign finding likely related to the presence of tiny cysts possibly cholesterol or hemosiderin deposition and less likely tiny calcifications. These tiny echogenic foci may come and go underneath
the surface epithelium and should
not raise concerns or result in follow up imaging.
In
the postmenopausal patient ovarian
size decreases
correlating with hormonal status and length of time since menopause Mean
postmenopausal ovarian volumes have been reported to range from 1.2 to 5.8 n ml with an ovarian
volume of greater than 8 ml considered abnormal in all cases. Some authors have suggested that a
unilateral ovarian size twice that of
the opposite side regardless of the size should also be
considered abnormal . Even though folliculogenesis has ceased
the postmenopausal ovaries are
not as
quiescent as initially though .
Small simple adnexal cysts measuring as large
as 3 cm have been reported
in up to 15% of postmenopausal women most of these spontaneously regress on serial
sonographic examinations. These
simple cysts seen early
in menopause most likely represent an occasional ovulatory
event or an atretic follicle. However any anechoic cystic lesion in a postmenopausal ovary should generally be referred to as a cyst. In late menopause although
ovulation is rare smaller cysts less than or equal to 1 cm
have been reported in up to 21 % of
women. TVS will detect these
cysts more readily than TAS because
of the higher resolution of the
higher frequency transvaginal probe
. These simple appearing cysts
measuring less than 1 cm
in maximal diameter do not need further follow up
and whether or not they are described in the final report can be left to the discretion of the interpreting physician. The
shape and size of the
uterus vary throughout life
affected mostly by hormonal status. The
mean measurement of the prepubertal uterus
is 2.8 cm in length and 0.8 cm in maximum
anteroposterior dimension with
the cervix accounting for two thirds of the total
length and contributing to the pear shaped appearance
. It is important to
remember that in the immediate post delivery state the neonatal uterus
can be slightly larger
owing to the effects of residual
maternal hormones,. For the same reason the echogenic endometrium
is well seen and a small amount of fluid can be present
in the endometrial cavity.
Point2:
Are U Surgeon?? Where is the danger?? It is in the post aspect &
ovarian fossa!!! The ureter and
internal iliac artery form the posteriorly and the external iliac vein superiorly. Any stitch,
clamp or bite can cause inclusion, clamping crushing or even through and
through cutting of the ureter. Like Gut this part also merit too much respect for radiation
heat and such thing must be kept in mind
in doubt and after opening the abdomen one feels it is difficult to
locate ureter in the true pelvis then it
the safe practice is to pinch up the P
periosteum at the brim level at the
bifurcation site and make a gentle incision by scissors and then by gentle
finger dissection the cord like structure (almost like spermatic cord) can be rolled, If you are a trainee then can
pass a soft rubber catheter beneath the
ureter and put a clamp on the rubber catheter but too much dissection from the
peritoneum may invite ischemic fistula later, Further at this
point of brim there is a danger of puncturing Ext iliac van ,Butyl pl
don’t be nervous ,Just gentle pressure for 10 minutes will cause stoppage bleeding, Vascular clips may cause harm. No
tie or extra needle pricks in a hurry please. The inferior aspect of the ovary
is slightly smaller than the
superior or tubal aspect and is bound to the uterine cornu by the ovarian ligament which lies within the broad
ligament .
There is another mountain with sleeping volcano
where too you can’t force / temp
an experienced Eagle to fly over that mountain!!!!! Where we face danger ?? The lateral surface
of the ovary . This is in contact with
the parietal peritoneum lining
the ovarian fossa and most of
the medial surface is covered by the
fallopian tube . Th anterior border of
the ovary is attached to the
mesovarium through which
the vascular channels and
nerves pass into the ovarian hilum. To remember ovarian vessels are the
direct lateral branch of abd aorta –a high pressure vessels. If a stitch slips
then the haematoma will trace quite high up .this also applies to pampiniform
plexus of veins ,The resultant haematoma(if the Asstt releases the clamp too
early before surgeon pushes the knot too firmly then such venous big size
haematoma can occur, Then too one
should call for Urosurgeonas , keep on
pressing the haeamtoma by hot mops(disposable desirable) till Urosurgeonas
arrives at theatre,. May have a requisition of 2 units of blood Tr/PCV), If U
are competent enough the after release of pressure U can try to locate the ureter at brim and the
again pass a rubber Catheter all around the
freed ureter ask the second asst to keep a gentle pull on it(ureter) and then one can pass N0 1 Chr catgut en masse
excluding the ureter with confidence (the life line-water line).. Usually two
stitches are required. Such an incidence also happens if A forces used for clamping
the I P ligament is as old as mine and gets slipped of its own before surgeon
puts the knot firmly. IN TLH this doesn’t happen except when electric line is
off and standbys line takes some time. . That is why some beginners do clap at
mesoaslpinx and remove the uterus ,Late the only ovary is removed . But be it
LH or open TAH double ligation of I P ligament safe. In CS cases pl do make a
habit of palpating the ureters so in times of need U can trace the ureter from brim to ureteric
tunnel thought such wide dissection(
making the ureters naked) are not recommended in good surgical practice
.
Point
4 : Uterus & sonologist :--From birth until 4 years of age
the uterus decreases in size. At
approximately 8 years of age the uterus
starts to grow preferentially in the fundus. The uterus continues to grow for several years
after menarche until it
reaches the mean dimensions of a
reproduction age uterus which are approximately 7 cm long and 4 cm wide. Parity
increases the size of the uterus with a multiparous uterus
measuring approximately 8.5 cm by 5.5 cm .
Following menopause
the uterus decreases in size. The
decrease in size is related to
the number of years since
menopause although the reduction in size is believed to be most
repaid durng the first decade following
menopause . The length of the normal post menopausal uterus
has been reported to range from 3.5
to 6.5 cm and the antero posterior dimension form 1.2 to 1.8 cm.
The
urinary bladder distal
ureters and urethra & USG
The
appearance of the urinary bladder
depends on the degree of distension. The
distended bladder will be round on a
superior transverse imaging plane. More inferiorly the pelvic musculature and bones
cause the bladder to be
square in the transverse
plane. The bladder wall is
homogenously echogenic and should be uniform in
thickness measuring less
than 3 mm when well distended. The ureteric and urethral orifices are visualized at the base and neck of the bladder respectively . IN the upper pelvis the ureter lies
anterior to the internal iliac artery
and posterior to the ovary More
inferiorly the ureter courses
anteromedially to lie within the inferomedial portion of the broad ligament
where it is in close
proximity to the uterine artery. The ureter then
runs anteriorly situated in
front of the lateral fornices of the vaginal
about 2 cm lateral to the
supravaginal cervix and then passes medially to enter the
trigone of the bladder anterior
to the vagina . The relationship of the
ureter to the ovary cervix
uterine artery and vagina is of clinical importance because
pelvic disease may obstruct the ureter resulting in secondary hydronephrosis The distal portion of the ureter just
proximal to the ureteral orifice is
often well seen on TAS through
the distended bladder . the distal
ureter and ureterovesical junction
can also be well seen on TVS
if the bladder is partially
distended. Hence TVS is an excellent means of searching for UVJ stones
especially in the pregnant
patient . The presence of a ureteral jet in the bladder on color Doppler is a normal finding on both TAS
and TVS and indicates that the
ureter is at least partially patent.
TVS enables better visualization of the trigoone one and posterior wall of the urinary bladder as well as the urethra in comparison to TAS.
To visualize the urethra the probe is placed at the introitus or just partially
inserted into the vagina and directed
upward .surrounding the inner
echogenic layer of the mucosa there is a
thin layer of smooth muscle and
then an outer sheath of striated muscle.
The longitudinally oriented smooth
muscle is thicker anteriorly in
the middle third of the urethra. The para urethral
gland of skene lie
posterior to the urethra near the UVJ
and empty through the periurethral duct near the external urethral orifice. Urethral diverticula
are distened and
obstructed urethral mucous
glands and are found posterior and lateral
to th urethra anywhere along its length. They may be a source of pelvic
pain and recurrent urinary tract
infection and can be
easily documented on TVS. They may be
round or horseshoe shaped
partially encircling the
urethra although these diverticula are usually
anechoic internal echoes may be
observed either diffuse or layering This non specific
finding may be secondary to infection or debris from stasis or
chronic inflammation. Echogenic
shadowing calculi may also be
observed in urethral Diverticula
as stasis predisposes to calculus
formation as well as infection
In
North America approximately 8% to 15% of couples is which the female partner is 15 to 45 years of age
experience some form of
infertility that is they have
not conceived after 12 months of
unprotected sexual intercourse .
normal fertility is considered to be between
20% to 22% per cycle
and approximately 50% after
three cycles. Therefore in a normal
population approximately 60%
of women will become pregnancy within 6 months 80%
within 12 months and 90%
within 18 months . In a fertility focused intercourse
study pregnancy was achieved in 76%
90% and 98% of cases by the first third and
sixth cycles respectively
the age of the female partner is of paramount importance
in making decisions about when to begin investigations . In
couples in which the woman is younger than 35 years of age 986. It is
generally accepted that infertility investigations be initiated after 12
to 18 months of unprotected
intercourse . however if the female partner is older than 35 years
of age has menstrual abnormalities a
history of pelvic disease or surgery earlier initiation of the
infertility work up may be considered It is important to
remember that infertility is a
couple’s issue and each couple will present with a different level of
desire to pursue infertility investigation and therapy . Evaluation and management of infertility diagnosis and therapy
will typically involve several members of a multi disciplinary team. Consensus documents outlining the optimal
work up of couples who present
with infertility and
optimal evaluation of the infertile female are
available from the Canadian
Fertility and Andrology society
and the American Society for Reproductive Medicine. These guide lines should be consulted for
best practices in determining the sequence
of diagnostic investigation and therapeutic intervention.
Ultrasonography is an integral and essential part of both the diagnostic and therapeutic steps
in ameliorating infertility . Although
the causes of infertility may have
only female factors only male
factors a combination of issues from each partner or are
idiopathic in nature the steps
taken toward resolution of the
couple’s inability to conceive
are shared Each step
in the diagnostic or therapeutic
process should entail clear communication and
involve education and
counseling so that the couple understands
the reasons for
each test is involved in
each decision at each
stage of therapy and has realistic expectations of the
therapeutic interventions. An ultrasound
examination during the
initial infertility consultation in clinics where ultrasonography is an
integral part of clinical practice. There is a tremendous amount of
information to be gained using
ultrasonography early in infertility
investigations. We believe that
imaging has become the de facto standard
for obtaining information once thought to be the purview of more conventional tests
and should now be considered as a
standard in infertility studies.
Uterine and ovarian abnormalities such as cysts tumors fibroids endometriomas hydrosalpinx and congenital abnormalities may be instantly visualized and appropriate action taken. In addition a conceptus may be visualized very
early in gestation.
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