Call Girls Varanasi Just Call 8250077686 Top Class Call Girl Service Available
Fetal Skull obstetrics and gynecological
1.
2.
3. INTRODUCTION
The fetal skull contains the delicate brain,
which may be subjected to great pressure as the
head passes through the birth canal. It is large in
relation to the fetal body and in comparison with
the mothers pelvis, therefore some adaptation
between skull and pelvis must take place during
labor. The head is the most difficult part to be
born whether it comes first or last.
4. INTRODUCTION– Conti..,
The fetal skull is the most important part of the
fetus from obstetric point of view.
Adaptation between the skull and the pelvis is
necessary to allow the head to pass through the
pelvis during labour without complications.
The fetal skull is made up of ossified &
incompressible base of skull & pliable vault or
cranium made of tabular (flat) bones separated at
their edges by sutures & fontanelles.
5. AREAS & regions
The skull is
considered as
divided into 3 parts –
VAULT, FACE &
BASE.
The areas are-
OCCIPUT, VERTEX,
SINCIPUT OR
BROW AND FACE
9. Importance of sutures
1. It Permit gliding movement of 1 bone over the
other during moulding of head which is needed for
vaginal delivery.
2. Digital Palpation of sagittal suture with fingers
during vaginal examination in labour gives
information about position, degree of internal
rotation & moulding of head.
10.
11.
12. FONTANELLES: Wide gap in suture line
FEATURES ANTERIOR POSTERIOR
Other name Bregma Lambda
Location Lies in medial plane between
2 halves of frontal & 2
parietal bones where 4
sutures (frontal, sagittal & 2
coronal sutures) meet
At junction of saggital suture
with 2 lambdoid sutures (where
3 sutures meet) in between
occipital & parietal bones.
Shape Diamond Triangular
Diameter 3 x 3 cm 1.2 x 1.2 cm
Ossified at One & half years (18 months) One & half month
13. Importance of fontanelles
1. Palpation of posterior fontanel during vaginal
examination denotes the position of occiput of head
(occipito-anterior or occipito-posterior position)
2. Palpation of anterior fontanel will denote the degree
of flexion of head. (if head is well flexed as in occipito-
anterior position, the anterior fontanel is not usually
palpable. If anterior fontanel is easily palpable, head
is usually deflexed as in occipito-posterior position.
14. Conti…
3. Helps in moulding of head.
4. Due to its membranous nature, the anterior fontanel
aids to accommodate the marked brain growth after
birth.
5. After birth, the fontanelles are useful to assess the
condition of baby. Ex: if dehydration then they are
depressed & in increased ICP then they may be tense &
bulging.
17. Transverse diameters
Bi parietal = 9.5 cm
Super subparital =
8.5 cm
Bi temporal = 7.5 cm
Bi mastoid = 7 cm
(smallest)
18. moulding
It is the alteration of the
shape of the fore coming
head while passing
through the resistant
birth passage during
labor.
Grading
Grade I
Grade II
Grade III
19. Importance
Slight moulding is inevitable and beneficial. It
enables the head to pass more easily, through the
birth canal.
Extreme moulding as met in disproportions may
produce severe intracranial disturbance in the
form of tearing of tentorium cerebelli or subdural
hemorrhage
Shape of the moulding can be a useful
information about the position of the head
occupation in the pelvis.
20. Caput Succedaneum
It is the formation
of swelling due to
stagnation of fluid
in the layers of the
scalp beneath the
girdle of contact
21.
22. Importance
It signifies static position of the head for a
long period of time
Location of the caput gives an idea about the
position of the occupied in the pelvis and the
degree of flexion achieved
In left position, the caput is placed on right
parietal bone and in right position on the
parietal bone
With increasing flexion, the caput is placed
more posteriorly
23. The Intracranial Membranes And Sinuses
The skull contains delicate structures,
some of which may be damaged if the
head is subjected to abnormal
moulding during delivery
Among the most important are the
folds of duramater and the venous
sinuses associated with them
These membranes are continuous with
the duramater that lines the cranium
24. The Intracranial Membranes And Sinuses
1. The falx ceribri
2. The tentorium cerebelli
3. The superior sagittal sinus
4. The inferior sagittal sinus
5. The great cerebral vein of galen
6. The straight sinus
7. Two lateral sinuses
25. 1.The falx ceribri
This is a sickle shaped fold of membrane
that dips down between the two cerebral
hemispheres and runs beneath the frontal
and sagittal sutures from the root of the
nose to the internal occipital protuberance
26. 2.The tentoriumcerebelli
This is a horizontal fold of durameter that
lies in the posterior part of the skull at
right angles to the falx cerebri
It is shaped like horseshoe and situated
between the cerebrum and the cerebellum,
over which it forms a sort of tent
The membranes contain veins or sinuses
that drains blood from the brain
27. 3.The superior sagittal sinus
This runs along the upper edge of the falx
cerebri from front to back
28. 4.The inferior sagittal sinus
This runs along the lower edge
of the falx cerebri in the same
direction
29. 5. The great cerebral vein of galen
This meets the inferior sagittal sinus at
the inner end of the junction between
the falx and the tentorium
30. 6. The straight sinus
This drains blood from both the great
cerebral vein and the inferior sagittal sinus
along the junction of the falx and tentorium
The point where it reaches the skull and
receives blood from the superior sagittal
sinus is known as the ‘ Confluence of sinuses’
31. 7.Two lateral sinuses
These passes from the confluence of sinuses
along the outer edge of the tentorium cerebelli
and carry blood to the internal jugular veins
The most vulnerable point of these structures
is where the falx is attached to the tentorium
The tentorium is liable to tear and there is a
danger of bleeding from the great cerebral
vein
32. summery
So far we have seen about the fetal
skull, the areas, landmarks, sutures, bones,
fontenelles ,moulding , caputsuccetaneum,
and the sinuses of fetal head in datail.
33.
34. Introduction
The science of genetics is concerned
with disease processes that can be
passed from one generation to the next
or that are related to a defect in
chromosomal reproduction. The range
of genetic problems is considerable.
Some are incompatable with life, others
may cause little description to the life
processes
35. Aim of genetic counselling
Detection and identification of
couples, who are at risk for having a
child with an inherited (chromosomal
or genetic) disorders
36. Etiological factors for fetal malformations
Chromosomal abnormalities
Single gene disorder polygenic or
multifactorial disorders
Teratogenic disorders due to exposure
of exogenous factors (drugs)
37. Risk factors for prenatal genetic counselling
Maternal risk factors
Maternal age above 35 years
Previous baby born with neural tube defect
Family H/O neural tube defect
Previous baby with chromosomal abnormalities
One or both parent carriers of sex linked or
autosomal traits
H/O recurrent miscarriages
38. Prenatal risk factors
Oligohydromnios
Polyhydromnios
Severe symmetrical fetal growth restriction
Abnormal USG findings
Uncontrolled DM in the periconceptual period
Contact with infections (tetarogenic)
Eg. rubella, CMV or intake of tetarogenic drugs
Presence of soft tissue markers of chromosomal
anomaly on USG
Abnormal maternal serum screenings
39. I.Chromosomal abnormalities
They result when mitosis and meiosis do not occur
in a normal fusion. Several type of these are described in
the following list..
1. Nondisjunction
2. Aneuploidy
3. Trisomy
4. Monosomy
5. Mosaicism
6. translocation
40. 1.Nondisjunction
It is the unequal distribution
of chromosomes to the daughter cells
during mitosis or meiosis. This
accounts for the majority of numeric
chromosomes abnormalities
41. 2.Aneuploidy
Is the result of numeric
chromosome errors. This usually results
in major developmental defects of the
fetus. Although many are incompatible
with life, certain combinations of these
defects can result in live born infants.
44. 5. Mosaicism
It is the presence of two or more
sets of cells that differ in their genetic
makeup but arise from single cells
45. 6. translocation
It is a structural chromosomal error that
result from breakage and restructuring of the
defects or an unbalanced carriers. If
translocation occurs without loss of genetic
information, the carrier does not suffer major
phenotype consequences if paired with a
normal person. However, two people with
translocation can produce offspring with
serious genetic abnormalities.
46. Manifestations of Chromosomal abnormalities
Chromosomal abnormalities occur once in
every 400 pregnancies
These result in mental retardation, congenital
anomalies or both
These can be minor or major or life-
threatening
Eg. Trisomy 21, Trisomy 13 & Trisomy 18 and
Turner’s syndrome & Klinefelter’s syndrome
47. II. Mendelian disorder
Many genetic disorders result from
mechanism described by Mendel. These are
classified according to characteristics of the
abnormal gene pattern.
1. Autosomal Dominant Disorder
2. Autosomal Recessive Disorder
3. X- Linked Recessive Disorder
48. 1.Autosomal Dominent Disorder
These are those in which the presence of a single
abnormal gene results in phenotypical changes or
diseases, despite the normally of the other members of
the gene pair
This may occur as a result of a mutation or by
transmission of an abnormal gene from one parent
A parent with an autosomal dominant disorder has a
50% chance of passing the abnormal gene to offspring
expression and penetration of some dominant very
greatly. Diagnosis of autosomal dominant disorders is
sometimes possible only after birth
49. 2.Autosomal Recessive Disorder
They are those in which both members of the
gene pair are abnormal
During meiosis, the abnormal gene is passed to
the gamate
However, if the other parent has normal genetic
structure, the abnormal gene contributed by the
affected parent usually is not expressed
The offspring, however are carriers of the defect
and are termed ‘ Heterozygous’ for the abnormal
gene
50. Conti..
If both parents carry recessive genes for a specific
disorder, one child in 4 is affected with that
disorder and one child in 2 is a carrier
Depict the process of recessive inheritance
Other genetic traits, such as eye color, hair color,
left or right hand dominance also passed to
offspring in this manner
51. 3.x- linked recessive disorder
They are present only on the X-
chromosomes
In normal women, one X-chromosomes in
each pair is inactive and may be visualized
as a ‘Barr Body’
A chromatic mass found in the
chromosome is random
The inactivation of the X-chromosome is
random
52. Conti..
A women with X-linked, but unless majority of
normal genes are inactivated the disease will not
be manifest
In reproduction, if the abnormal gene is active and
passed to the gamate, the male offspring will
manifest the disorder, because the X-chromosome
in each male cell is active
Female offspring may be carrier of the disorder.
Half of the offspring will either be carriers or will
manifest the disorder
53. Manifestation of medalian disorder
Single gene defects account for a considerable
number with genetic problems associated with
medelian disorder
Careful history taking and appropriate genetic
testing can identify fetuses affected with these
disorders
Eg. OI (Osteogenesis Imperfecta), Marfan
syndrome, Cystic fibrosis, Phenylketonuria(PKU),
Sickle cell anemia, hemophilia A& B, Duchanne’s
muscular Dystrophy, Fragile X syndrome
54. III. Multifactorial defects
Many common birth defects are multifactorial
A genetic predisposition to a lower threshold for
development abnormalities
Genetic combination may have a cumulative effect
by adding factors, such as family history, chance of
certain environmental factors
Eg. Exposure to toxic chemicals or radiation, use of
recreational drugs
56. Procedures for early detection of fetal abnormalities
Bio- physical
& Bio-
chemical
Trimester
wise
Invasive &
Non
invasive
57. bIochemical analysis
Maternal serum alpha fetoprotein (MSAFP)
AFP is an oncofetal protein, is produced by yolk sac and fetal liver
The highest level is reached around 13 week and then decreases
Maternal serum level reaches a peak around 32 weeks
MSAFP level elevated in following conditions
Wrong gestational age
Open neural tube defects
Multiple pregnancy
Rh isoimmunization
Anterior abdominal wall defects
Renal abnormalities
Low level of found in Trisomy (Down syndrome), Gestational Trophoblastic
diseases.
58. Conti…
Inhibin A
It is a dimeric glycoprotein. It produced by the corpus luteum and the
placenta
The raised level indicate Down syndrome
others
HCG / UE3 /PAPP-A
HCG is produced by the syncytotrophoblast of the placenta secreted into
the blood to both mother and fetus the blood and the urine values reaches
maximum level from 100 to 200 IU/ml between 60 to 70 days of pregnancy
high level of HCG in the following conditions -multiple pregnancy
/hydatidiform mole/choriocarcinoma/Down syndrome
the lower level in pregnancies under spontaneous abortion
PAPP-A is secreted as HCG.it as an immuno suppressants in pregnancy. low
level is associated with increased risk of preeclampsia and IUGR
59. Screening methods- 1st trimuster
•USG ( NT)
Bio
physical
•Free b-hcG
•PAPP-A
Bio
chemical
60. Conti…
Time to test : between 11-14 weeks
Values:
PAPP-A - Reduce
b hcG - Increased
NT - Increased In Trisomy
Advantages:
Once a women is screen positive, diagnostic tests
should be done early. Targeted USGS during the
second trimester and fetal ECHO are to be done
when NT more than or equal to 3 mm
61. Second trimester screening
It is done between 15 to 22 weeks
MSAFP:
This is done between 15 to 20 week values of 2.5 multiples of median with weight of
the mother. Increased levels 85% defect neural tube defects. Lower level indicates
stillbirths, miscarriages, neonatal deaths
Triple test:
combined test of MSAFP, HCG and UE3 Down syndrome
In an affected pregnancy MSAFP & UE3 low and HCG is high
It performed at 15 to 22 weeks
Quadruple test:
Combined test of MSAFP, UE3 ,dimeric inhibin-A and HCG
It detects 85% trisomy 21 where
HCG - increased
UE3 -reduced
Inhibin-A- elevator
MSAFP - reduced
62. Invasive procedures
Chorionic villus sampling
Is performed transcervically between 10-13 weeks and
transabdominally from 10 weeks to term. The following
condition can be detected eg. Down syndrome, Turner
syndrome, neural tube defects.
Amniocentesis
It performed after 15 weeks under USG guidance
transabdominally. The fetal cells obtained in this and are
subjected for cytogenetic analysis.
cardocentesis
percutaneous umbilical cord sampling. It may leads to
abortion, preterm labor, IUD etc. Fetal anemia, bleeding
disorders, RH diseases, hemoglobinopathies etc are to be
obtained.
63. Non invasive procedures
As fetal DNA and biophysical measures such as
USG/ MRI are to be carried out throughout the
pregnancy. example all congenital anomalies,
chromosomal abnormalities, structural
abnormalities
64. summery
so far we have see about the genetic
counselling, their aims, etiology, risk
factors, types, procedures, screening
methods in various aspects of procedures
65. conclusion
Genetic counselling gives you
informatics about how genetic conditions might
affect the family and the baby. It helps to
understanding genetic disorders in important in
learning more about promoting health and
preventing disease
66.
67. Journal application
Topic: Supporting patient autonomy and informed
decision making in prenatal genetic testing
Authors: Katie Stoll & Judith Jackson
Conclusions: Genetic counsellors have played a
crucial role in supporting patient to make informed
and value consistent decisions in the prenatal
genetic setting since prenatal screening and
diagnosis were first possible. A complete set of
tests such as of DNA and expanded carrier testing
become more routine in obstetrical care, the
percentage of patients who work directly with a
genetic counselor to help them navigate through
the decision making process will necessarily
decrease.
