O&G Flashcards
(158 cards)
1
Q
Helpful videos
A
PRENATAL TESTING https://www.youtube.com/watch?v=_esAs0vVFd4
https://www.youtube.com/watch?v=_esAs0vVFd4&t=38s
PROM https://www.youtube.com/watch?v=MY7w76rC2rE
ECTOPIC https://www.youtube.com/watch?v=Q_qiUYIBR7o
PLACENTA PREVIA
https://www.youtube.com/watch?v=xnRIF8SDYf8
FETAL GROWTH ABNORMALITIES https://www.youtube.com/watch?v=t0k7LSx9iL0
PPH https://www.youtube.com/watch?v=FVvcmY9Skzc
NORMAL LABOR https://www.youtube.com/watch?v=cTTJoNQSXmo
OVARIAN PATHOLOGY
https://www.youtube.com/watch?v=oZeagsS6Fws
ENDOMETRIAL CANCER
https://www.youtube.com/watch?v=CJZr9_LATgQ
CERVICAL CANCER
https://www.youtube.com/watch?v=5KEAnfLj1pE
STAGE OF LABOR
https://www.youtube.com/watch?v=h7nOZ2kNfW4
PRE-ECAMPLSIA
https://www.youtube.com/watch?v=RB5s85xDshA
MENSTRUAL CYCLE
https://www.youtube.com/watch?v=tOluxtc3Cpw
GERM CELL OVARIAN TUMOURS
https://www.youtube.com/watch?v=8Ymvt2vBM1I
PID
https://www.youtube.com/watch?v=eYk3GdBw-28
2
Q
Uterus changes during life
A
NEONATE
Cervix larger than fundus
PREPUBERTY
Tube like uterus with cervix and uterus same size
PUBERTY Pear like (adult) with fundus larger than cervix
Ovaries begin at 1cc until around 6yo then gradually increase in size
TURNER SYNDROME
XO kids. Horseshoe kidney, aortic coarctations, prepuberty uterus and streaky ovaries
3
Q
Embryology
A
MULLERIAN DUCTS
Uterus, fallopian tubes, upper 2/3 vagina
WOLFFIAN DUCTS (SHOULD REGRESS) Vas deferens, seminal vesicles, epididymis
UROGENITAL SINUS
Prostate, lower 1/3 vagina
“stuff that makes kidneys and uterus is in same soup. pour soup down back of belly on both sides. upper part makes kidney, lower makes uterus. 2 puddles fuse in pelvis. clean up operation in pelvis to cleave to get central cavity capable of carrying baby”
4
Q
Problems in embryology
A
FAILURE TO FORM
Only have soup on one side. No kidney on that side and usually have unicornuate uterus.
FAILURE TO FUSE
Soup fails to fuse in pelvis. On spectrum of no fusion with uterine didelphys to mostly fused bicornuate
FAILURE TO CLEAVE
Septate uterus
5
Q
Failure to form
A
MULLERIAN AGENESIS
Mayer-Rikitansky-Kuster-Hauser syndrome
Vaginal atresia, absent or rudimentary uterus and normal ovaries. Kidneys have issues in half cases (agenesis/ectopia)
UNICORNUATE UTERUS - 4 VARIANTS
- unicornuate + communicating cavitatory rudimentary horn
- unicornuate + non-communicating cavitatory rudimentary horn
- unicornuate + non-cavitatory rudimentary horn
- isolated unicornuate (most common 35%)
If see unicornuate need to look for rudimentary horn. Horns can have endometrium which gives rise to many causes of pain . Increase risk of miscarriage and life threatening bleed if in noncommunicating horn as it can rupture
6
Q
FAILURE TO FUSE
A
UTERINE DIDELPHYS
Complete uterine duplication (2 cervices, 2 uteri and 2 upper 1/3 vagina). Vaginal septum present 75% time.
BICORNUATE
Either one cervix unicollis or 2 bicollis. Seperation of uterus by deep myometrial cleft. Vaginal septum 25% time. Fetal loss much less of an issue than septate
T SHAPED
DES related anomaly. Historical trivia. DES synthetic oestrogen given to prevent miscarriage in 40s. Daughters of these patients had vaginal clear cell carcinoma and T shaped uterus
7
Q
Failure to cleave
A
SEPTATE
Two endometrial canals separated by fibrous or muscular septum. Determine on MRI, this changes surgical management. Increased risk infertility and recurrent abortion. Septum has poor blood supply. Improved outcomes with resection of septum.
ARCUATE
mild smooth concavity of uterine fundus. Normal variant. Not associated with infertility or obstetric complications
8
Q
Bicornuate vs septate
A
BICORNUATE
Heart shaped fundal contour. No significant infertility issues. Resection of septum has poor outcomes
SEPTATE
Fundal contour is normal. Infertility issues, implantation fails if on septum. Resection of septum can help.
9
Q
HSG
A
Part of infertility workup or to prove success of tubal ligation.
Day 7-12 as least chance of pregnancy, also dont want to push endometrium through the tubes into pelvis.
Contraindications: pregnancy, active pelvic infection, active bleeding, contrast allergy
Irregular uterine filling defects may be scarring or adhesions (can be trauma from prior curettage). Round filling defects polyps or fibroids. Bubbles from not primed catheter.
Proximal blockage shows abrupt cutoff with no distal opacification. Distal blockage shows dilated tubes with no pelvic spillage.
10
Q
Salpingitis Isthmica Nodosa (SIN)
A
Nodular scarring of fallopian tubes. Aunt Minnie.
Proximal 2/3 tube. Likely inflam/infect. Associated with infertility and ectopic preg.
11
Q
Uterine AVM
A
Congenital or acquired (more common). Can have fatal bleed. Previous D+C can cause this, therapeutic abortion, caesarian section or multiple preg.
Serpiginous tubular anechoic structures within myometrium with high velocity flow
12
Q
Intrauterine adhesions (Ashermans)
A
Scarring in uterus usually secondary to D+C, surgery or pregnancy. Can be infection/PID.
Either on HSG with irregular filling defects or MRI with T2 dark bands. Usually infertility results.
13
Q
Endometritis
A
Spectrum of PID. 2-5 days after delivery, especially in prolonged labor or premature rupture. Fluid and thickened endometrial cavity. Can have gas in cavity.
14
Q
Pelvic floor
A
3 compartments which are maintained by endopelvic fascia, levator ani and urogenital diaphragm.
ANTERIOR
Bladder and urethra
Cystocoele is bladder >1cm below pubococcygeal line
MIDDLE
vagina, cervix, uterus and adnexa
Uterine prolapse is descent of cervix or posterior vaginal fornix >1cm below pubococcygeal line
POSTERIOR
anus and rectum
Rectocoele is abnormal rectal bulging usually anteriorly, bulging relative to anal canal, due to weakness in rectovaginal fascia.
15
Q
Fibroids (uterine leiomyoma)
A
Benign smooth muscle tumour - most common uterine mass. Like estrogen and most common in reproductive age. Grow rapidly in pregnancy and involute in menopause.
Can look like anything. Usually hypoechoic with peripheral blood flow and shadowing. Can have peripheral popcorn calcs
HYALINE (CLASSIC)
Most common. T1 dark T2 dark, homogenous enhancement
HYPERCELLULAR
Dense smooth muscle, respond well to embolization T1 dark, T2 bright, homogenous enhanement
LIPOLEIOMYOMA
Rare fat containing subtype. Hyperechoic on USS. Fatty uterine mass CT. Fat sat on MRI. T1 bright, T2 bright, rim enhancement
Degeneration
Lack enhancement. Can degenerate in 4 ways.
Classic - outgrows blood supply, get proteinaceous material
Red - in pregnancy due to venous thrombosis
Myxoid - uncommon
Cystic - uncommon
16
Q
Uterine leiomyosarcoma
A
Risk of malignant transformation to this is low 0.1%. Look like fibroid but rapidly enlarge. Areas of necrosis often seen
17
Q
Adenomyosis
A
Endometrial tissue that has migrated into myometrium. Most common in multiparous women of reproductive age, especially if history of uterine procedures.
Usually generalized but spares cervix. Can cause marked enlargement of uterus, especially posterior wall.
Can be shown on USS or MRI. Hyperechoic adenomyosis with hypoechoic muscular hypertrophy. MRI shows thickening of junctional zone to over 12mm (normal <5mm) which can be focal or diffuse. Small T2 bright cystic areas (Venetian blind artefact on USS)
18
Q
Thick endometrium
A
Measured without fluid in canal. >5mm in postmenopausal women should be sampled. Premenopausal can get up to 20mm
Estrogen secreting tumours will thicken endometrium - granulosa cell tumours of ovary
HNPCC have 30-50 x risk of endometrial cancer
Post meno bleeding
Endometrium <5mm probably atrophy. Endometrium 4-5mm maybe cancer and gets biopsy
19
Q
Tamoxifen changes
A
This is a SERM (selective estrogen receptor modulator). Acts like estrogen in pelvis, blocks estrogen effects in breast. Used for breast cancer but marginally increases risk of endometrial cancer 1% per year.
Can cause subendometrial cysts and development of endometrial polyps 30%. Tamoxifen endometrium often thick, up to 12mm
20
Q
Endometrial fluid
A
In premeno this is common. In post meno may mean cervical stenosis or obstructing mass.
21
Q
Endometrial cancer
A
90% adenocarcinoma. Possible exception leiomyosarcoma.
Usually post menopausal bleeding.
Step 1 USS for endometrial thickness. If thick biopsy if abnormal then MRI for staging
MRI
T1 iso, T2 mildly hyper, homogenous enhancement, restricted diffusion.
Staging via FIGO system
STAGE 2
disease defined as cervical stroma invasion, high risk for LN mets. Key is C+ phase, if normal cervical enhancement then no invasion. Changes management to preop radiation to cervix along with Radical hysterectomy rather than TAH.
STAGE 1A (<50% myometrium) to STAGE 1B (>50% myometrium) increases risk of LN disease.
STAGE 3
Local or regional spread
STAGE 4
Involvement of bladder or rectum
22
Q
Cervical cancer
A
Usually squamous cell related to HPV (90%). Once you have parametrial invasion (stage2b) or involvement of lower 1/3 vagina it gets chemo/radio. Also FIGO staging.
STAGE 2A
Spread beyond cervix but no parametrial invasion - surgery
STAGE 2B
Parametrial involvement but no extension to sidewall - chemo/radio
PARAMETRIUM
fibrous band that separates supravaginal cervix from bladder. Extends between layers of broad ligament. Important as uterine artery is in here so need for chemo once invaded. Cervix normally has T2 dark ring, if this is lost its invaded beyond here.
23
Q
Solid vaginal masses
A
Can be primary (clear cell adenocarcinoma or rhabdomyosarcoma) or secondary (cervical or uterine carcinoma protruding into vagina).
LEIOMYOMA
Rare in vagina but can occur usually in anterior wall
SQUAMOUS CELL CARCINOMA
Most common cancer of vagina 85%. Associated with HPV
CLEAR CELL ADENOCARCINOMA
Along with T shaped uterus in DES - historical and rare
VAGINAL RHABDOMYOSARCOMA
Most common tumour of vagina in kids. Bimodal age distribution 2-6 and 14-18. Anterior wall near cervix.Solid T2 bright enhancing mass in vagina/lower uterus in kid
Met to anterior upper vagina 90% upper genital tract
Met to posterior lower vagina 90% GIT
24
Q
Cystic vaginal/cervical masses
A
NABOTHIAN CYSTS
Common, usually on cervix. Inflammation causing epithelium plugging of mucous glands
GARTNER DUCTS CYSTS
Result of incomplete regression of Wolffian ducts. Along anterolateral wall of upper vagina. If at urethra can cause mass effect on urethra.
BARTHOLIN CYSTS
Obstruction of Bartholin glands (mucin secreting glands from urogenital sinus). Below pubic symphysis. If infected can suture open to allow continual drainage. “Bartholin Below
SKENE GLAND CYSTS
Cysts in these periurethral glands can cause recurrent TI and urethral obstruction
25
Ovary
Ovarian volume normal up to 15ml. Post meno shouldnt be over 6ml.
Follicles seen in early cycle are <5mm. By day 10 a dominant follicle emerges up to 20mm. Follicle then ruptures, releases egg and forms corpus luteum. Can have physiologic fluid in pelvis at this time
CUMULUS OOPHORUS
Collection of cells in mature dominant follicle that protrude into follicular cavity and signal imminent ovulation
26
Theca lutein cysts
Type of functional cyst related to overstimulation from bHCG. Large cyst with multilocular cystic appearance - spoke-wheel
Multifetal pregnancy
Gestational trophoblastic disease (moles)
Ovarian hyperstimulation syndrome
27
Ovarian hyperstimulation syndrome
Complication associated with fertility therapy (5%). Ovaries with theca lutein cysts, then ascites and pleural effusions. May also have pericardial effusion. Risk of ovarian torsion and hypovolaemic shock
28
Paraovarian cyst
Cyst in adnexa but not in ovary. Adjacent to ovary or tube. Very low rate of malignancy.
29
Post meno ovary
Abnormal if it either exceeds upper limit of normal or is twice size of other ovary. Small cysts seen in around 20% post meno. Post meno ovaries are atrophic, lack follicles and can be difficult to find.
Ovarian volume will decrease from 8cc at 40 to 1cc at 70. Max ovarian volume post meno is 6cc.
Not simple cyst if irregular septations, papillary projections or solid elements
30
Benign ovarian masses
```
Physiologic and functioning follicles
Corpus Luteum
Haemorrhagic cysts
Endometrioma
Benign cystic teratomas (dermoids)
Polycystic ovaries
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31
Functioning ovarian cysts/follicles
Affected by menstrual cycle. Benign and usually <25mm. Will change/disappear in 6 weeks. If it doesnt change/disappear it is considered nonfunctioning (not under hormonal control)
Simple cysts >7cm may need MRI evaluation. Risk torsion.
32
Corpus Luteum
Normal CL arises from dominant follicle. Can be large 5-6cm with variable appearance. Most common is solid and hypoechoic with 'ring of fire'. Thin echogenic rim. Moves with ovary
CL vs ectopic:
Both can have 'ring of fire". Most ectopics in tube, CL is in ovary. Ectopic usually hyperechoic to ovary, CL hypoechoic to ovary. Ecopic has thick echogenic rim and moves separate to ovary
33
Endometrioma
Targets young women in reproductive years. Can cause chronic pelvic pain with menstruation.
Triad of infertility, dysmenorrhoea and dyspareunia
Rounded mass with homogenous low level internal echoes and increased through transmission 95% cases
Dont tend to change on follow up (haemorrhagic cysts do). Can have small echogenic foci adhering to walls.
Most common location for endometriosis is uterosacral ligts and in or near c section scar.
1% endometriomas become malignant to endometroid or clear cell carcinoma. Malignancy very rare in endometrioma <6cm, usually larger than 9cm. lso usually >45yo
Endometrioma T1 bright from blood, T2 dark from iron (shading sign)
34
Haemorrhagic cyst
A ruptured follicle can bleed internally and re-expand. Homogenous mass with increased through transmission. Similar look to endometrioma, lacy fishnet appearance. Doppler absent.
Haemorrhagic cyst will go away in 1-2 cycles, endometrioma wont.
Post meno will occasionally ovulate. Follow in 6-12 weeks.
35
Dermoid
Usually in young women 20-30 and are most common ovarian neoplasm in patients <20. "tip of iceberg" sign is classic buzzword and refers to absorption of most of USS beam at top of mass.
Cystic mass with hyperechoic solid mural nodule (Rokitansky nodule or dermoid plug). Septations in 10%
MRI T1 bright from fat and will suppress on FS imaging (endometriomas and haemorrhagic cysts wont).
1% malignant transformation usually to squamous cell ca. Risk factors size >10cm and age >50.
Endometrioma - clear cell
Dermoid - squamous
36
PCOS
Typically overweight girl with acne, pencil moustache.
>10 peripheral simple cysts <5mm. String of pearls appearance
Ovaries enlarged >10cc although 30% will have normal volume
37
Ovarian masses - think malignant if
Complex cystic adnexal masses with thick septations and papillary projections (nodule with blood flow)
Solid adnexal masses with variable necrosis
38
Serous ovarian/Cystadenocarcinoma/Cystadenoma
Serous are most common type of ovarian malignancy.
60% serous tumours benign and 15% borderline, remaining are malignant.
Women of childbearing age. Typically unilocular with few septation. Papillary projections common and suggest malignancy.
If ascites, 70% have mets (70% have peritoneal involvement at time of diagnosis)
39
Mucinous ovarian cystadenocarcinoma
Often large mass. Typically multiloculated although septa are thin. Papillary projections less common. Can get low level echoes from mucin.
Get pseudomyxoma perotineii with scalloping of solid organs.
40
Serous vs mucinous
SEROUS
Unilocular with few septations
Papillary projections common
MUCINOUS
Multilocular with more septations
Papillary projections less common
41
Endometroid ovarian cancer
Second most common ovarian cancer (serous 1, mucinous 3)
Bilateral 15% time. 25% women will have concomitant endometrial cancer (ovary is met).Endometriomas can turn into this rarely.
Ovarian mass + endometrial thickening will be endometrioid cancer OR granulosa theca cell tumour which produce estrogen and cause endometrial hyperplasia
42
Large mass differential
BFM in adult:
Ovarian masses mucinous and serous
Desmoids
Sarcomas
BFM in kid:
Askin tumour (PNET/Ewings)
Pleuropulmonary blastoma
43
Fibroma/Fibrothecoma
Benign ovarian tumour in middle aged women. Similar to fibroid.
USS hypoechoic and solid. MRI T1 and T2 dark with band of dark T2 signal around tumour on all planes. Calcs rare
Similar conditions
Meigs syndrome = ascites, pleural effusion and benign ovarian tumour
Brenner tumour = epithelial tumour of ovary in women 50-70s. Fibrous and T2 dark. Calcs common 80%
44
Struma ovarii
Subtype of ovarian teratoma. Multilocular cystic mass with intensely enhancing solid component.
MRI low T2 signal in cystic areas which is colloid. Tumours contain thyroid tissue. Clue may be patient hyperthyroid or in thyroid storm.
45
Ovarian mets
10% of malignant ovarian tumours are mets. Primary most commonly colon/gastric/breast/lung and other ovary. Bilateral solid tumours classic
KRUKENBURG TUMOUR
Mets to ovary from GIT usually stomach
46
Ovarian torsion
Rotation of ovarian vascular pedicle resulting in arterial or venous obstruction. Typically associated with cyst or tumour. Has dual blood supply so flow less accurate in diagnosing.
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Most constant finding is large ovary.
Unilateral large ovary over 4cm
Mass on ovary
Peripheralised cysts/follicles
Free fluid
Lack of arterial or venous flow.
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47
Hydrosalpinx
Buzzword is "cogwheel appearance" referring to normal longitudinal folds of fallopian tube becoming thickened/ "string sign: is incomplete septae. "waist sign' is tubular mass with indentations of its opposing walls.
Most common cause PID. Can also be endometriosis, tubal cancer, post hysterectomy and tubal ligation.
48
Pelvic Inflammatory Disease
Infection or inflammation of upper genital tract. Will see hydrosalpinx with ill defined margin of uterus. Can progress to tubo-ovarian absess and can get bowel or urinary changes.
49
Paraovarian cyst
Congenital remnant from Wolffian duct. Do not distort adjacent ovary. Can mimic exophytic cyst but are separate to ovary
50
Ovarian vein thrombophlebitis
Usually in postpartum women with acute pelvic pain and fever approx 10 days after delivery. 80% time on right. Tubular structure with enhancing wall and thombus
51
Peritoneal inclusion cyst
Inflammatory cyst of peritoneal cavity that occurs when adhesions envelop an ovary. Adhesions cannot absorb fluid. Expanding pelvic mass from normal secretions by active ovary..
Classic is patient with prior pelvic surgery now with pain. Could say with history of PID or endometriosis, needs to occupy pelvic recess and contain the ovary.
Lacks walls, passive shape that conforms to surrounding structures. Entraps ovary
52
Gestational trophoblastic disease
Marked bHCG rise. Hyperemesis often part of stem. Moles common in age >40 and prior moles make you more likely to get another.
53
Hydatidiform mole
Most common form, benign. 2 subtypes
COMPLETE MOLE
Classic, 70%. Involves entire placenta with no fetus. Pathogenesis is fertilization of an egg which has lost its chromosomes.
1st trimester USS shows uterus filled with echogenic solid highly vascular mass described as "snowstorm"
2nd trimester USS vesicles that make up mole enlage into individual cysts. "Bunch of grapes"
PARTIAL MOLE
30%. Only portion of placenta. Fetus present but triploid. Fertilization of an ovum by 2 sperm. Lethal to fetus
US placenta enlarged with areas of multiple diffuse anechoic lesions and may see fetal parts.
Can see theca lutein cysts in molar pregnancies
54
Invasive mole
Invasion of molar tissue onto myometrium. Can see it after treatment of hydatidiform mole. Echogenic tissue in myometrium. MRI better to see muscle invasion. Focal myometrial masses, dilated vessels and areas of haemorrhage/necrosis
55
Choriocarcinoma
Very aggressive malignancy that forms only trophoblasts. Spreads locally into myometrium and parametrium then haematogenous to any site of body. Very vascular. Classic scenario is bHCG rising following evacuation of molar pregnancy. USS shows highly echogenic solid mass. Treatment is methotrexate.
56
Penile fracture
Fracture of corpus cavernosum and surrounding sheath, the tunica albuginea.
T1 axial. Black line tunica albuginea will be interrupted. Look for haemorrhage in corpus cavernosum.. Stigmata can be suboptimal angulation (Peyronie's) from fibrous scar formation
57
Prostate adenocarcinoma pattern
Peripheral zone 70%. Most common cancer obv
Transition zone 20%
Central zone 10%.
Central gland Most common BPH
Cancer is T2 dark with restricted diffusion, early enhancement and rapid washout
If PSA <20 very low chance of bone mets. Bone scan is best study for prostate mets
58
Prostate staging
STAGE 2
Confined by capsule T2
Abutment of capsule without bulging
STAGE 3
Extension through capsule (T3a)
Bulging of capsule or extension through it
Extension through capsule is most important factor governing treatment.
Seminal vesicles and nerve bundle are behind prostate and can get invaded.
59
Prostate Ca
1/6 men will get it and 3% die from it. People who die are:
Gleason scores 8-10
Advanced clinical stage (mets)
PSA>20
People with Gleason <6, PSA <10 and staging <2a are unlikely to die of prostate ca
Most say hormone therapy around stage 2b
60
PSA
Antigen produced by normal prostate and incorporated into ejaculate for the purpose of dissolving cervical mucus. Also leaks out into blood in small amounts normally or larger when prostate damaged.
Post prostatectomy, normal is 0. Should think recurrence when >0.2. After radiation anything >2 is abnormal
61
Gleason
Grade, score and group.
GRADE
Histological pattern
1 normal, 5 very abnormal, rest inbetween
SCORE
Sum of two most common grades. More common pattern always first. Scores less than 6 not usually reported.
GROUP
Uses pattern scores to reflect actual risk. Removes confusion over one 7 being worse than another.
62
PIRADS
Scores calculated using data from DWI, T2 and enhancement. Tumour in transition zone is determined primarily from T2 (all T's), peripheral zone is from DWI
63
Benign prostatic hypertrophy
Very common. Volume of 30cc used as cutoff. Most commonly involves transitional zone (central gland) where cancer is rare. Median lobe is the one that hypertrophies and protrudes up into bladder.. Can cause bladder outlet obstruction, wall thickening and diverticulae
Buzzword is J shaped or fish-hook or Hockey stick ureter as this curves around enlarged prostate into bladder
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BPH NODULES
Transitional zone (central gland)
T2 heterogenous
Can restrict diffusion
May enhance and washout
```
64
Prostate summary
PERIPHERAL ZONE TUMOUR
T2 dark, restricts and enhances/washes out early
PERIPHERAL ZONE HAEMORRHAGE
Typically post biopsy
T2 dark but sometimes bright
Restricts with no enhancement
CENTRAL GLAND/TRANSITIONAL ZONE TUMOUR
T2 dark, restricts, early enhancement/washout
BPH
T2 dark, restricts and can enhance
65
Male pelvic cysts
MIDLINE
prostatic utricle
mullerian duct cyst
ejaculatory duct cyst
LATERAL
seminal vesicle cyst
Diverticulosis of the ampulla of vas deferens
66
Seminal vesicle cyst (lateral)
Classic is unilateral cyst that is lateral to prostate. Can get large and look midline. Can be congenital or acquired
CONGENITAL
Associated with renal agenesis, vas deferens agenesis, ectopic ureter insertion, PCKD
ACQUIRED
Obstruction often from prostatic hypertrophy or chronic infection/scarring
Classic history is prior prostate surgery
67
Prostatic utricle cyst (midline)
Focal dilatation in prostatic urethra. Communicate with urethra and can cause dribbling
Hypospadias is most common associated. Other associations include Prune Belly syndrome, Downs syndrome, unilateral renal agenesis and imperforate anus
Tendency for superinfection.
68
Mullerian duct cyst (midline)
Failed regression of caudal ends of the mullerian duct.
| Does not communicate with urethra and does not have same associations as utricle cyst
69
Utricle vs Mullerian cyst
UTRICLE
Pear shaped and usually smaller
Will NOT extend above base of prostate
Communicates with urethra so can opacify on RUG
MULLERIAN
tear drop
Extends above base of prostate
Does not communicate with urethra so cant opacify on RUG
Both have tiny malignant potential or various types
70
Prostate abscess
Thick walled septated heterogenous cystic lesion anywhere in prostate. Usually bacterial with E.coli. When chronic can cause cavitatory prostatitis. Usually imaged via transrectal USS as it gives urologist option to drain at same time.
71
Testicular torsion
Testis and spermatic cord twisting within serosal space. Doppler USS.
Testis will be darker, asymmetrically enlarged and if chronic will be shrunken. Absent arterial flow is most obvious look However you can have preserved arterial flow with increased resistance and decreased diastolic flow.
Bell clapper deformity describes abnormal high attachment of tunica vaginalis, increases mobility and predisposes to torsion. Usually bilateral so the contralateral side also gets orchidopexy
Viability is based on how torted and for how long. Want to be in OR under 6 hours ideally
HIGH FLOW STATE/HYPERAEMIA
Either dealing with epididymoorchitis or detorsion. Orchitis painful, detorsion not.
72
Epididymitis
Inflammation of epididymis. Most common cause of acute onset scrotal pain in adults. Typical cause is chlamydia or gonorrhoea in young adults, more likely E.coli from UTI in older adults.
Epididymal head most affected. Increased size and hyperaemia are findings. Can also have orchitis with this but isolated orchitis rare. Usually begins in tail*
73
Orchitis
Typically progresses from epididymitis. Isolated only occurs in mumps. Asymmetric hyperaemia.
Swelling of testicle can be so severe that it compromises blood flow.
74
Testicular trauma
Rupture vs fracture. Surgery needed if rupture. Fracture and haematomas dont need surgery
RUPTURE
Disrupted tunica albuginea, heterogenous testicle, poorly defined testicular outline.
FRACTURE
Intact tunica albuginea, linear hypoechoic band accross parenchyma of testicle, well defined testicular outline.
75
Testicular cancer
Risk factors are cryptorchidism, gonadal dysgenesis, Klinefelters, trauma, orchitis and maybe testicular microlithiasis.
Mos classic is male 18-35 with history of undescended teste now has seminoma
Male 18-35 with mystery retroperitoneal LNs next step is uss scrotum
Most testicular tumours met via lymphatics to nodes at renal hilum. Exception is choriocarcinoma which mets haematogenously
76
Testicular cancer subtypes
GERM CELL 90%
Seminoma 50% in 4th decade
Non-seminoma 50% (teratoma, yolk sac, mixed germ cell)
NON GERM CELL (10%)
Sertoli
Leydig
77
Flow chart
Intratesticular mass (more likely malignant) - solid (more likely malignant), cystic (more likely benign).
Extratesticular mass (more likely benign)
Hypoechoic solid intratesticular mass is cancer till proven otherwise
78
Seminoma
Most common testicular tumour, best prognosis, very radiosensitive. Classic around 25. Usually homogenous hypoechoic mass.
79
Non-seminomatous germ cell tumour
Mixed germ cell tumour (yolk sac, teratoma, choriocarcinoma). Heterogenous with large calcs and cystic spaces.
80
Shrinking testicular tumour
Germcell tumours can sometimes burn out and regress into small mass or tiny calcification after growing too fast for its blood supply. Can still be viable tumour there.
81
Testicular lymphoma
```
Primary or secondary. Highly variable look. Diffusely enlarged ill defined hypoechoic testicle or multiple hypoechoic masses. Age is primary discriminator usually occur over 60.
Mostly unilateral (60%) but bilateral lymphoma is the most common bilateral testicular tumour. Immunosuppressed at risk of developing extranodal/testicular lymphoma
```
82
High yield testicular tumour trivia
Seminoma most common 18-35, best prognosis, radiosensitive
Lymphoma most common >60
Lymphoma usually diffuse B cell
Lymphoma usually unilateral but is most common bilateral tumour
Homogenous and microcalc = seminoma
Cystic elements and macrocalc - Mixed germ cell tumour
Most test tumours met via lymphatics
Choriocarcinoma met via blood
Gynaecomastia seen with Sertoli Leydig tumour
Bilat cancer = lymphoma
Bilat hypoechoic mass = lymphoma
Bilat solid testicular mass and epididymal mass = sarcoid
Seminoma and choriocarcinoma elevated bCG
Mixed germ cell and yolk sac elevated AFP
83
Staging
Para-aortic, aortic, caval region N1-3
| If mets to pelvic thats M1
84
Cancer mimics
Infarct
Haematoma
Infection
Epidermoid cyst (benign mass, onion skin look)
Tubular ectasia rete testes (common benign finding from obliteration of efferent ducts. Next to mediastinum testes)
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Male infertility
OBSTRUCTIVE
CBAVD (congenital bilateral absence of vas deferens) seen in Cystic Fibrosis
Ejaculatory duct obstruction, prostatic cysts
Associated renal anomalies
NON OBSTRUCTIVE
Varicocoele, cyptorchidism, anabolic steroid use, erectile dysfunction
RARE
Pituitary adenoma making prolactin
Kallman syndrome, Klinefelter syndrome, Zinner syndrome
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Varicocoele
Most common correctable cause of infertility. Uni or bilateral. isolated right sided think retroperitoneal process causing compression or right gonadal vein
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Cryptorchidism
Undescended testes, usually in inguinal canal. Increased risk Ca. Most common in prems.
COMPLICATIONS
Malignant degeneration of both testes, infertility, torsion, bowel incarceration related to associated indirect inguinal hernia.
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Early pregnancy
Menstrual age: Embryologic age + 14 days
Embryo: 0-10 weeks (menstrual age)
Fetus: >10 weeks (menstrual age)
Threatened abortion - bleeding with closed cervix
Inevitable abortion - cervical dilatation and/or placental and/or fetal tissue hanging out
Incomplete abortion - residual products in the uterus
Complete abortion - all products out
Missed abortion - fetus is dead but still in uterus
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Intradecidual sign
Early gestational sac. When covered by echogenic decidua is very characteristic of early pregnancy. See around 4.5 weeks. Need to differentiate from small fluid in sac
DOUBLE DECIDUAL SAC
Positive sign early preg. Visualizing layers of decidua. Outside decidua capsularis then small amount of fluid then inside decidua vera
90
Yolk sac
First structure visible within gestational sac. When GS measures 8mm should see YS. Oval, round, fluid filled and <6mm.
Located in chorionic cavity, hooked up to umbilicus of embryo by vitelline duct
Shouldnt be >6mm, <3mm or be solid or calcified
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Amnion
Membranes of amniotic sac and chorionic space typically remain separated by thin layer of fluid until about 14-16 weeks at which point fusion is normal. If amnion disrupted before 10 weeks, fetus might cross into chorionic cavity and get tangled in fibrous bands. This is etiology of fibrous band syndrome which can result in decapitations/amputations etc
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Double bleb sign
Earliest visualization of embryo.Two fluid filled sacs (yolk and amniotic) with flat embryo in middle
93
Crown rump length
Used to estimate gestational age, more accurate than menstrual history. Embryo normally visible at 6 weeks.
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Anembryonic pregnancy
Gestational sac without embryo. Either very early or non viable pregnancy. Should see yolk sac at 8mm GS.
Large GS without yolk sac and distorted contour is pretty reliable for non viable pregnancy.
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Pseudogestational sac
Seen in presence of ectopic preg. Little bit of blood in uterine cavity with surrounding bright decidual endometrium.
Not same as anembryonic pregnancy
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Subchorionic haemorrhage
Common. Percentage of placental detachment is prognostic factor most strongly associated with fetal demise. Haematoma >2/3 circumference of chorion has 2x increased risk of abortion.
IMPLANTATION BLEEDING
Nonspecific term referring to small subchorionic haemorrhage that occurs at attachment of chorion to endometrium
97
Pregnancy failure
DIAGNOSTIC
CRL >7mm with no heart beat
MSD >25mm and no embryo
No embryo with heartbeat >2wks after USS with GS without YS
No embryo with heartbeat >11days after USS with GS and YS
SUSPICIOUS
No embryo >6wks after LMP
MSD 16-24mm and no embryo
No embryo with heartbeat 13 days after USS with GS without YS
No embryo with heartbeat 10days after USS with GS and YS
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Pregnancy unknown location
When neither intrauterine preg or ectopic preg is seen in setting of positive bHCG, Usually just very very early preg.
Normal early preg
Occult ectopic
Complete miscarriage
Follow up bHCG and USS
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Ectopic preg
Hx of PID, tubal surgery, endometriosis, ovulation induction, previous ectopic, IUD.
Majority in fallopian tube 95%, usually ampulla. Small proportion in proximal tube within uterus (interstitial) which are high risk for growth rupture and catastrophic haemorrhage. Possible but rare to have in cervix, ovary or abdominal cavity.
bHCG 1500-2000 should see GS. Around 5000 should see YS. Normal doubling time makes ectopic less likely
TUBAL RING SIGN
Echogenic ring around unruptured ectopic preg 95% specific
HETEROTOPIC PREG
Baby in uterus and other ectopic. Rare and seen in those on ovulation drugs or prior bad PID
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Ectopic preg big 3
1. Live preg/YS outside uterus - definite ectopic
2. Empty uterus and anything in adnexa 75-85% ectopic. Moderate free fluid raises this to 97%
3. Nothing in uterus and moderate free fluid 70%.
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Fetal growth/biometry
4 standard measurements made in 2nd and 3rd trimester scans
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BIPARIETAL DIAMETER (BPD)
Recorded at level of thalamus from outermost edge of near skull to inner table of far skull
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HEAD CIRCUMFERENCE
Recorded at same slice. Doesnt include skin
ABDOMINAL CIRCUMFERENCE
level of junction of umbilical and left portal vein. Does not include subcutaneous tissues
FEMUR LENGTH
Longest dimension of femoral shaft. Epiphysis not included
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Weight and age
ESTIMATED FETAL WEIGHT
calculated by machine based on either BPD and AC or AC and FL
GESTATIONAL AGE
Estimates most accurate in early preg and become less precise. Age in first trimester made from CRL (accurate to 0.5w). 2nd (accurate to 1.2w) and 3rd (accurate to 3.1w) typically by BPD, AC, HC and FL - composite GA
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IUGR
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SYMMETRIC
Small head
Skinny body
Same throughout pregnancy
Siphylis
Scotch whiskey (EtOH)
Some extra chromosomes
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ASYMMETRIC
Abdomen is small
Aching belly
Abnormally high BP
Alastic skin (Ehler Danlos)
Asymmetric time interval (3rd trimester)
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MCA doppler
Proximal 3rd of vessel.
Should be high resistance waveform with continuous forward flow of diastole.
Abnormal when fetal brain experiences hypoxia there is a reflex response. Increase in diastolic flow (less resistance)
Cerebroplacental ratio. ratio of pulsatility in MCA and umbilical artery used to evaluate brain sparing reflex and predict outcomes. >1:1 is normal.
Fetal anaemia variety of causes (maternal alloimmunization and parvovirus are most common). MCA doppler is useful with increase in peak systolic
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Umbilical artery systolic/diastolic ratio
Resistance in umbilical artery should progressively decrease with gestational age. 2-3 at 32 weeks. Elevated ratio means high resistance which are seen in preeclampsia and IUGR.
Worse than elevated ratio is absent or reversed diastolic flow associated with very poor prognosis.
Think of early life as just a muscle then get more like a brain. Need more diastolic flow and less resistance
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Macrosomia
Babies that are too big. Maternal diabetes most common cause, usually T2DM. T2DM can also have small babies from hypoxia from microvascular disease. If too big, complications during delivery can occur (shoulder dystocia, brachial plexus injury) and after delivery (neonatal hypoglycaemia, meconium aspiration)
ERBS PALSY
Injury to upper trunk brachial plexus (C5/6) commonly seen in shoulder dystocia. Aplastic or hypoplastic humeral head/glenoid in a kid think Erbs palsy.
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Amniotic fluid
Up to week 16, amniotic fluid is result of filtrate from the membranes. After week 16 is made by fetus urine and maintained by swallowing of urine and renal function.
If too little (oligohydramnios) should think kidneys arent working. If too much (polyhydramnios) should think swallow or other GI problems. Common cause of too much is also maternal diabetes
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AMNIOTIC FLUID INDEX
Measuring vertical height of deepest pocket in each quadrant then summing all 4 measurements
Normal is 5-20
Oligo <5cm
Poly >20cm or single pocket >8cm
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Normal development trivia
BRAIN
Choroid large and echogenic. Should be <3mm separation from medial wall lat vent, if more think ventriculomegaly
Cisterna Magna 2-11mm (too small chiari, too big dandy walker)
FACE/NECK
Fulcrum of upper lip is normal
LUNGS
Normally homogenously hypoechoic and similar to liver
HEART
Papillary muscle can calcify (echogenic foci in vent). Normal but can be associated with Downs
ABDOMINAL
If one artery next to bladder - 2 vessel cord. Bowel should be less than 6mm in diameter. Bowel should not be more echogenic than bone. Are adrenals are very big in newborns relatively.
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Normal pictures
CYSTIC RHOMBENCEPHALON
Normal rhombencephalon is present as cystic structure in posterior fossa at 6-8 weeks.
PHYSIOLOGIC MIDGUT HERNIATION
Midgut normally herniates into umbilical cord around 9-11 weeks., dont call it omphalocoele
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Placenta
First see it around 8 weeks. Shaped like disc around 12 weeks. Granular with smooth cover (the chorion). Underneath basal surface there is a normal retroplacental complex of decidual and myometrial veins.
As it ages it gets hypoechoic areas, septations and randomly distributed calcs
VENOUS LAKES
Incidental finding of no significance. Look like focal hypoechoic areas under chorionic membrane. Can have flow.
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Variant placental morphology
BILOBED PLACENTA
Two near equal sized lobes connected by thin strip. Risk of type 2 vasa previa (vessel cross the internal os), post partum haemorrhage from retained placental tissue and velamentous insertion of cord
SUCCENTURIATE LOBE
One or more accessory small lobes. Increased risk of type 2 vasa previa, post partum haemorrhage from retained placental tissue.
CIRCUMVALLATE PLACENTA
Rolled placental edges with smaller chorionic plate. high risk for placental abruption and IUGR.
Too thin = <1cm. Placental insufficiency, maternal hypertension, maternal DM, trisomy 13, trisomy 18, toxemia of pregnancy
Too thick = >4cm. Fetal hydrops, maternal DM, severe maternal anaemia, congenital fetal cancer, congenital infection, placental abruption
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Placental abruption
Painful
Premature separation of placenta from myometrium. Mother doing cocaine is classic but also in HTN. Subchorionic haemorrhage is in category. Retroplacental abortion is bad one. "disruption of retroplacental complex"
Placental abruption will disrupt the retroplacental complex of blood vessels. Myometrial contractions/fibroids will displace the retroplacental complex
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Placenta previa
Painless
Low implantation of placenta that covers part or all of internal cervical os. Need empty bladder to look for this
Low lying (within 2cm of internal cervical os), marginal (to edge of internal os but not covering it), complete (covers os), central (centered over os)
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Placenta creta
Abnormal insertion of placenta which invades myometrium. Risk factors are prior c-section, placenta previa, advanced maternal age. Moth eaten or swiss cheese on USS with vascular channels. Thinning of myometrium another sign.
ACCRETA
Most common 75% and mild. Villi attach to myometrium without invading
INCRETA
Villa partially invade myometrium
PERCRETA
Really bad one. Villi penetrate myometrium beyond serosa, can be invasion of bladder or bowel
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Placenta chorioangioma
Hamartoma of placenta most common benign tumour of placenta. Well circumscribed hypoechoic near cord insertion. Flow within mass pulsating at fetal HR is diagnostic. If large and multiple can sequester platelets and causehigh output failure (fetal hydrops)
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Umbilical cord
3 vessel cord normal 2 arteries, 1 vein
TWO VESSEL CORD
Normal variant 1%. Usually left artery missing. Happens more in twin preg and maternal DM. Increased association with chromosomal abnormalities and various fetal malformations. In isolation doesnt mean much
117
Velamentous cord insertion
Cord inserts into fetal membranes outside placental margin then has to travel back through membranes to placenta (between amnion and chorion). More common with twins and increases risk of IUGR and growth discordance amongst twins.
118
Marginal cord insertion
Almost a velamentous insertion, within 2cm of placental margin. More common in twin preg
119
Vasa previa
Fetal vessels that cross or almost cross internal os. More in twin and variant placental morphology.
Type 1: fetal vessels connect to velamentous cord within main placental body
Type 2: fetal vessels connect to bilobed placenta or succenturiate lobe
120
Nuchal cord
Term used to describe cord wrapped around neck of fetus.
121
Umbilical cord cyst
Common 3% and usually single. Omphalomesenteric duct syct is usually peripheral and allontoic cyst is usually central. If they persist into 2nd or 3rd trimester can be associated with trisomy 13 and 18
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Downs Syndrome
Congenital heart disease: >1/2, usually AV canal and VSD
Duodenal atresia: see >22 wks
Short femur length non specific
Echogenic bowel non specific
Choroid plexus cyst non specific
Nuchal translucency >3mm in 1st trimester
Nuchal fold thickness >6mm in 2nd trimester
Echogenic focus cardiac ventricle non specific but increases risk Downs
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Nuchal lucency
Measured between 9-12 weeks. Anechoic area between occiput/neck and skin should be <3mm.
Positioning neck is critical to avoid false positive. Neutral neck, nasal bone visualised and head mid sagittal.
Maternal blood also sampled for bHCG and PAPP-A
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Amniotic band syndrome
Fetus needs to be in amniotic cavity and stay out of chorionic cavity. If amnion disrupted and fetus goes through, can get caught in fibrous bands resulting in amputation to decapitation.
XRay of hand or babygram showing fingers or hand/arm amputated with everything else normal OR fetal USS with bands entangling arms or legs of fetus
125
Hydrops
This is bad. Can be from immune or non-immune causes. Most commonly Rh sensitization from prior preg. Can be TORCH, turners, twins related things, alpha thalassaemia.
2 of following: pleural effusion, ascites, pericardial effusion and subcutaneous oedema. Placentomegaly may also be shown. Increase in peak systolid flow on MCA doppler
126
Chiari 2/Open Neural Tube Defect
Hole in lower back from neural tube defect (myelomeningocoele). This lets CSF drip out from epidural space. Resultant low volume CSF. CSF needs to be at certain pressure to distend ventricular system. If underdistended, hindbrain structures drop into caudal system. Caudal herniation of cerebellar vermis, brainstem and 4th ventricle is halmark of Chiari 2.
Normal pressure needed to shape ventricular system, also in part to shape skull.. Low pressure and abnormal distension of developing brain results in incomplete stretching of front part of skull. Results in LEMON shaped rostral skull. Lemon shape goes away in 3rd trimester.
BANANA SIGN
Loss of normal bilobed cerebellum shape
2nd and 3rd trimester
More sensitive/specific
LEMON SIGN
Flat or concave frontal bones.
Only in 2nd trimester
Less sensitive/specific, also seen in Dandy Walker, absent corpus callosum
127
Ventriculomegaly
Multiple causes including hydrocephalus (C and non-C). and cerebral atrophy.
Aqueductal stenosis is most common non-C
Ventricular atrium >10mm is too big
Dangling choroid hanging off wall more than 3mm is too big
128
Choroid plexus cyst
Incidental findign and in isolation means nothing.
| Incidence is howver higher in Trisomy 18, 21, Turners syndrome and Klinefelters syndrome
129
Facial clefts
Most common facial anomaly. 30% time is with chromosome abnormality. 80% of babies with cleft lip will have cerebral palsy.
130
Cystic hygroma
Complex cystic mass in posterior neck in antenatal period. Association with Turners and Downs
131
Anencephaly
Most common NTD. Total absence of cranial vault and brain above orbits. Not compatible with life
132
Congenital diaphragmatic hernia
Abdominal contents push into chest. 85% on left (liver protective).
High mortality due to association with pulmonary hypoplasia.
All kids are malrotated
133
Echogenc Intracardiac Focus
Calcification in papillary muscle, usually LV. Dont mean much in isolation but higher association with Trisomy 21 and 13
Downs patients 12%
Normal popn 5%
134
Double Bubble
Duodenal atresia
135
Echogenic bowel
Can be normal variant but also associated with CF, Downs, viral infections and bowel atresia
Normally isoechoic to liver, shouldnt be brighter than bone
136
Sacrococcygeal teratoma
Most common tumour of fetus or infant. Solid or cystic masses, typically large. Can cause mass effect on GI system, hip dislocation, nerve compression causing incontinence, and high output cardiac failure.
Can cause issues with premature delivery, dystocia, haemorrhage of tumour.
80% benign with those presenting in older infants having higher malignnt potential. 47% external to pelvis, 9% internal to pelvis or 34% dumbell internal and external.
137
Autosomal Recessive Polycystic Kidney Disease
Massively enlarged bilateral kidneys with oligohydramnios.
138
Posterior urethral valves
Bilateral hydro on fetal USS or 3rd trimester
139
Short femur
Below 5th percentile think of skeletal dysplasia
140
Things that grow during pregnancy
Babies
Splenic artery aneurysms
Renal AMLs
Fibroids
141
Incompetent cervix
When shortened, cervix is associated with high risk of premature delivery. Short if endocervical canal <25mm
142
Hydronephrosis
80% pregnancies, mechanical compression ureters. Affects right more than left
143
Fibroids
Tend to grow in early pregnancy secondary to elevated estrogen. Progesterone will have opposite effect, inhibiting growth in later pregnancy. Stretching of uterus may affect arterial supply and promote infarcts and cystic degeneration.
144
Uterine rupture
Most commonly in 3rd trimester at site of prior c section. Other risk factors unicornuate uterus, prior uterine curettage, trapped uterus (persistent retroflexion from adhesions) and interstitial implantation
145
HELLP syndrome
Haemolysis, Elevated Liver enzymes, Low Platelets
Most severe form of preeclampsia and favours young primigravid women in 3rd trimester. 20-40% end up with DIC. Will show subcapsular hepatic haematoma
146
Peripartum cardiomyopathy
Dilated cardiomyopathy in last months of preg to 5 months post partum.
Cardiac MRI shows global depressed function and non vascular territory subepicardial Gd enhancement
147
Sheehan syndrome
Pituitary apoplexy in postpartum female wth large volume haemorrhage causing acute hypotension. Can stroke out pituitary in this scenario. MRI appearances variable but probably T1 bright. Ring enhanement around empty sella is a late look
148
Ovarian vein thrombophlebitis
Cause of post partum fever. RF include endometritis and c-section. Right side affected 5x more than left. Enlarged ovary or thrombosed adjacent vein
149
RPOC
Continued bleeding after delivery or induced abortion. Echogenic mass within uterine cavity. Presence or absence of flow is variable. Thickening of endometrium >10mm with some reflective structures and shadowing representing parts of fetus.
Associations MTOP, 2nd trimester miscarriage and placenta accreta
150
Endometritis
Inflammation or infection of endometrium. Fever, uterine tenderness and recent c-section (or prolonged labour). Thickened heterogenous endometrium with/without fluid or air
151
Placental terminology
Monozygotic (identical) twins or dizygotic (not identical) twins.
Dizygotic are always dichorionic and diamniotic
Placenta of monozygotics is more variable and depends on timing of fertilized ovum splitting (<8 days diamniotic, >8 days monoamniotic)
Later the split, worse things do
152
Monochorionic vs dichorionic
MEMBRANE THICKNESS
Thin or hard to see is 2 layers so monochorionic
Thick 1-2mm is 4mm so dichorionic
TWIN PEAK SIGN
Beak lie tongue between 2 membranes of dichorionic diamniotic. This excludes monochorionic preg
T SIGN
Absence of twin peak sign. Dont see chorion between membrane layers. Monochorionic preg
153
Twin growth
Use normal growth charts in 1st and 2nd trimester. Femur length works best for twin age in late preg. More than 15% difference in fetal weight or abdominal circumference between twins is considered significant.
Monochorionic twins share a placenta. If abnormal vascular connections, blood can be transferred from one fetus to another which is bad.
154
Twin Twin Transfusion Syndrome TTTS
Happens in monochorionic twins when a vascular communication exists in placenta. One larger twin and one smaller twin. Larger one usually gets hydrops and dies and smaller one does better.
Unequal fluid in amniotic sacs. Small twin gets oligohydramnios and can be "shrink wrapped" or "stuck to wall of uterus". Small twin also has high resistance umbilical artery
TOPS (Twin Oligohydramnios Polyhydramnios Sequence)
Oligo for donor (small)
Poly for recipient (large)
155
Twin Reversed Arterial Perfusion Syndrome (TRAP)
Severe variant of TTTS. Recipient/large doesnt develop a heart just uses heart of donor twin.
Recipient dont do well, deformed upper bodies, die in utero.
Donor twin normal and does ok as long as strain on heart isnt too much although they can die too if strain too large (>70% EFW of donor twin).
Could show as doppler USS with flow toward acardiac twin or umbilical vein flow away from acardiac twin.
156
Twin Anaemia Polycythaemia Sequence TAPS
Fetal fetal transfusion but no difference in amniotic fluid. Transfer of haemoglobin with one anaemic twin and one with polycythaemia.
Can occur after incomplete laser treatment for TTTS. Elevated MCA doppler peak systolic in anaemic twin.
157
One dead twin
At any point in preg, one twin can die. Bigger problem for surviving twin. Fetus papyraceous is word for dead flat fetus
158
Twin embolization syndrome
Embolized necrotic dead baby being transferred to living ferus. Can result in DIC, tissue ischaemia and infarct. Can only happen in monochorionic pregnancy
