Methods of TAS:--Measurement technique
When
EAS(AUS is) performed a water based ultrasound gel placed on the skin surface
acts as an acoustic couplant by
obliterating the air interface
between the transducer head and
abdominal wall.
Methodology of TVS: At
what step of TVS procedure gel is
to be applied & when & by what
agent wasing of the probes is done by members??
what solution is used for washing the probe in between ?? Your own
methodolgy & preferences fo good quality image & safety of woman
concerned?? When TVS is performed the vaginal transducer Step A)
ultrasound gel is placed inside
the condom tip before pulling it over the transducer. Or o the outer side
of probe and condom is drawn over the prbe ? Transduced (vaginal probe) is covered
with a disposable condom to
reduce the risk of cross infection and the.
Step B) Washing the probe in between
bhyy what solution?? The probe
itself is washed with antiseptic solution antiseptic solution and rinsed thoroughly between
patients because of the possibility of a condom defect on visible to the naked eye . Latex rather than plastic
condom should be used because
they are less likely to break during use.
How do members measure a growing or dominat
follicle?? This question arisesas the
technique for measuring follicle size is
not standardized .I am not talking of
volume of follicle but mean diameter .How many us measures three diameters of a
Dominalt follicle and the measn is mentioned and trigger is decided/ or add
extra HMG?? Ans; There are several apparoved methodology., For instance measurements may be taken from the Procedure 1:-outer edge on one side to the inner edge on the opposite side is the most common method or Procedure
2 :-from the outer edge of both sides
follicle . BUT follicles are rarely spherical so that the examiner must
decide where to take
measurements and usually selects two
or three positions that seem to most
accurately portal the real dimensions: lasty -Procedure 3: Two dimensions vs three diameters of a Dominal
follicle àHow relevant it is?? Ans:-As because
the choice of where to measure
is subjective recording three
dimensions offers little advantage over recording to two dimensions and
is impractical when large numbers
of follicles must be measured . Differences in how
measurements are taken can account for 1-2 mm differences in recorded follicle size.
Endometrial thickness is customarily measured from outside to outside in an anterior posterior view at the widest point ; if
measured inside to outside the
difference can be as much as 2
mm The difference in how thickness is measured may explain
some of the differences in values
deemed critical for successful
implantation reported in peer reviewed publications . In
addition to thickness the Why the A,B, & Ctypes of endometrial
patern in endometrial pattern is frequently
reported as initially described in 1984
there were three patterns type A, a multilayered
triple line endometrium consisting of a
prominent outer line or layer a central
hyperechogenic line and an inner
hypoenchogenic or black region , type B an intermediate isoechogenic pattern with the same reflectivity as the surrounding myometrium and a non prominent
or absent central echogenic line
type C an entirely homogeneous
endometrium without a
central echogenic line. Subsequently others reversed the ABC
pattern Descriptions of endometrial pattern in the medical literature may follow either
classification system. Most present
day authors no longer use
ABC pattern. Why-What is the members
view on not being popular method of classification of endometrium , By
xcontrast peopleare happy with previous teerminology i.e in descriptibe pattern line may follow
either classification system
. Most present day authors no longer use ABC classification but instead use the terms A) triple
line and homogeneous to
describe the two most common endometrial patterns. A third term post ovulation
is used to describe the B) bright pattern seen during
the mid luteal phase.
To perform sonohysterography either a 5.3
French flexible hysterosalpingogram catheter with a 3
ml latex plastic ballon
or a pediatric Foley cath eter is filled with 0.9% normal saline and inserted midway into
the cervix which has been cleansed with iodine solution
or other antiseptic . Th balloon is inflated with water and the
speculum is withdrawn and replaced with the vaginal US
transducer . A 30 ml syringe is
used to slowly infuse 0.9% normal
saline while scanning the uterus
first longitudianlly fanning from cornu
to cornua nd then turning the
transducer 90 degrees in a transverse
fashion from the external
cervix to th fundus.
Follicular
and endometrial appearance
in the normal and OI cycle
Follicular phase day 3
Ultrasound for OI is ordinarily performed on the
third to fifth cycle day to provide a baseline
from which to monitor follicular development
and to rule out the presence of
ovarian or endometrial pathology
antral follicles before
day 3 are normally 3-6 mm in
diameter and 4-6 per ovary in number, The presence of eithr or more follicles in the 3-6 mm range on each ovary with none
large signifies the potential
development of 10-20 or more
preovulatory follicles when
gonadotropin stimulation is
used. Approximately 25% of women have this type of ovary but with out OI will develop
only one or two preovulatory
follicles due to normal functioning of the ovarian
hypothalamic pituitary
feedback system. the
presence of eight or more 6-8 mm follicles
in each ovary on day 3 or late in unstimulated cycles is diagnostic of classical polycystic
ovarian disease . Other abnormal
findings at the beginning of the cycle
may include ovarian cysts large
than 10 mm endometrial hyperplasia and endometrial polyps
described late in this chapter. The endometrial
thickness at the completion of menstruation should be
less than 6 mm,
Follicular
phase day 6 : appearance of the dominant follicle
The lead follicle destined to become dominant
normally grows at the rate of 1 mm a day during
the first half of the follicular phase
of the cycle until it
reaches 10 mm and then grows at a rate of 2 mm
per day . The lead follicle may
be 7-8 mm by day 6 . In gonadotropin
OI cycles US performed
on day 6 or after
three days of stimulation will confirm that follicles are developing As a general rule all
follicles that were previously
smaller and are 6 mm or larger
on day 6 of gonadotropin
OI cycles will be 10 mm or
larger on day 6 of
gonadotropin OI cycles will be 10 mm
or larger by day 12-14 when a
spontaneous Lh surge occurs
or hCG is administered for IUI
or timed intercourse . In spontaneous
cycles only the lead or
dominant follicle will ordinarily continue to
develop and ovulate .
Follicular phase
day 12 : appearance of
preovulatory follicle capable of ovulation
By day 12 the dominant follicle should
be 16-18
mm or larger and capable of ovulation
if an LH surge occurs or if hCG
is administered . In spontaneous cycles further enlargement may occur with the
follicle reaching a size of 22-24
mm immediately before
ovulation An increase
of 3 or even 4 mm in 24
hours may occur at this time. In
controlled ovarian hyperstimulation cycles stimulated with hMG or FSH
the follicular size at ovulation
is often smaller ranging from 16
to 20 mm. it is at this time that the decision
is made about whether to proceed with IUI or to withhold IUI and proscribe intercourse for 4-5 days if there is an excessive number
of preovulatory follicle Any follicle
that has attained a size of 10 mm or larger may ovulate a mature
egg although most eggs from
10-12mm follicles will be
immature and not ovulate .
Follicles which are 8mm or larger may have acquired
FSH receptors and if they fail to ovulate may continue to grow and produce
estrogen resulting in
ovarian hyperstimulation syndrome .
Follicular phase
day 12: endometrial pattern
Endometrial
thickness and pattern on the day of the
spontaneous LH surge on hCG administration are intimately associated with implantation success
or failure Both wall to wall
endometrial thickness and endometrial pattern
have been reported to be related
to implantation success but th former may be more important . The endometrial pattern typically changes from an entirely homogenous
hyperechogenic pattern in the
first few days of the menstrual period through an intermediate stage with a thin central
line and echogenecity similar to the myometrium to a triple
lien appearance with a clearly demarked
center line and echogenecity of the outer lines less than
half that of the myometrium
before ovulation. After ovulation
the triple line pattern becomes
obscured by the increasingly
hyperechogenic pattern of the post ovulation luteal phase
endometrium Implantation does not occur or occurs at a reduced rat per follicle if the endometrium lacks a triple line pattern on the day
of hCG
administration in COH cycles. Abnormal patterns seen at this time include fluid within the endometrial cavity which if persistent is incompatible with implantation fluid
collection within the fallopian tube
or tubes and small polyps
that were not visible
earlier in the cycle A homogeneous
pattern may be an indication of
endometrial or uterine pathology Multiple leiomyomata synechiae diethylstilbestrol anomalies or adenomyosis were found in 94% of IVF patients
with a homogenous endometrial
pattern at the end of the proliferative phase in 305
of patients with triple line pattern
and endometrial thickness < 9
mm and in 6% of patients with triple
lien pattern and thickness >
9mm
Follicular
phase day 12: endometrial thickness
Endometrial
thickness measured by TUS correlates
well with histological
endometrial maturation . In spontaneous
cycles endometrial
thickness increases from a mean
of 4.6 mm during
menstruation to 12.4 mm the day of the LH surge . The increase in thickness is generally constant
averaging less than 1 mm per day but
it may increase by 2 mm a day
in the late proliferative phase
. Endometrial thickness from outer
wall to outer wall at the
widest point > 9 mm on the day
of LH surge or hCG injection is associated with a higher pregnancy rate compared to thickness < 9 mm.
In spontaneous and OI cycles implantation rarely occurs when thickness is less than 6 mm
when thickness is 6-8 mm the incidence
of biochemical
pregnancies is increased and there is a lower ongoing pregnancy rate than when thickness is
> 9 mm Endometrial thickness
< 6 mm is found in 2% of
COH cycles and 9% of CC cycles Endometrial thickness < 6 mm is also found in 9%
of spontaneous ovulatory cycles where
it may be th cause of unexplained
infertility . When
endometrial thickness is less
than 9 mm the deficiency can be corrected
in many cases by administration of
exogenous estrogen as
described .
Luteal
phase day 21
Implantation occurs
approximately six days after ovulation and seven
days after a spontaneous LH
surge or hCG injection. The endometrium by this
time should show a
completely homogenous hyperechogenic pattern
A mixture of type C post ovulation pattern and triple line at the time
of implantation 5-6 days after
ovulation is associated with inadequate progesterone and a lower pregnancy rate. If luteal insufficiency
is suspected it can be corrected with administration of exogenous progesterone as described . Endometrial thickness normally decreases by 0.5 mm the
day after the LH surge LH
surge but then increases an
average of 2 mm between ovulation
day and 5-6 days later. A decrease
in endometrial thickness two
days after ovulation compared to
before ovulation is believed
to be detrimental to
implantation . Endometrial
thickness can be increased by administration of exogenous estrogen
even at this late date.
Pelvic pathology
Ovarian cysts
Clear
thin walled ovarian cysts usually
represent atretic Graafian follicles
that did not ovulate but continued to enlarge
sometimes reaching3-4 cm in diameter over several months Hemorrhagic and non hemorrhagic luteal ovarian cysts may be confused with endometriomas. They can be distinguished from endometriomas which have a
homogenous texture by
their heterogeneous nature and because they are associated with elevated progesterone concentrations as late as the first 3-5
menstrual cycle days . Both
type of functional cyst occur
frequently following OI and do not require
treatment other than a cycle
of rest . When they are found on an
initial US they may be treated
with oral contraceptive pills before initiating OI . Ovarian
cysts larger than 4 cm should be removed not
drained smaller cysts without cancer characteristics may either be followed until they resolve or suppressed with OC pills
Aspiration of single
unilateral cysts before
superovulation for IVF does
not increase the number of preovulatory follicles
or th number of oocytes recovered.
Functioning hemorrhagic
and non hemorrhagic corpus
luteum and simple cysts inhibit
follicle develop progesterone
production Benign ovarian neoplasms and endometriomas may inhibit follicle
development by pressure . In addition endometriomas may expand and rupture during stimulation Ovulation induction should not be attempted when endometriomas are larger
than 2 cm . When endometriomas
are smaller than 2 cm mild IU with
oral drugs may be attempted for p to three cycles.
Simple ovarian
cysts can be distinguished from periovarian cysts
originating from fallopian tube nabothain cysts of the cervix and mesothelial cysts by
their position. The first two are often similar in size to a developing
dominant follicle. Mesothelial
cysts are a collection of serous fluid secondary
to pelvic adhesions. Mesothelial
cysts can become very
large but are
distinguishable by their position
and irregular shape
Sonohysterogarphy for endometrial polyps
endometrial adhesions submucosal fibroids and hydrosalpings
An
endometrial polyp that appears only
as an irregularity on routine will be
sharply outlined on an SHG
scan and is clearly distinguishable from a submucosal
fibroid . Endometrial polyps and submucosal fibroids intruding into the endometrial cavity may impair implantation
and development of the embryo and impede passage of the IUI
catheter. If a polyp is found
it should be removed to improve the chances
of pregnancy and to rule
out the possibility of malignancy . Endometrial synechiae
will be highlighted as dark
strips appearing against
the bright hyperechogenic saline contrast material ,. Endometrial synechiae may not be apparent on conventional US but
should be suspected if there
is marked irregularity of the endometrial lining
accompanied by failure to increase in thickness
during OI.
Hydrosalpinx
although best visualized on hysterosalpingogram can also
be demonstrated on SHG The possibility of hitherto
unsuspected tubal obstruction is
immediately raised if more than
the customary pressure is
required while infusing
saline or performing IUI
using the tubal perfusion technique. The
site of tubal obstruction whether
corneal or distal will be immediately appearent
on SHG when performing
any perfusion of the uterus
or tubes prophylactic antibiotics should be given and the day of procedure should be
selected so that the patient is
not menstruating A customary course of antibiotics for this purpose if patients
are not allergic is doxycycline
100 mg twice daily beginning before and continuing for four days
following the procedure
No comments:
Post a Comment