Fetal abnormalities Flashcards
What is Mayer-Rotitansky syndrome?
Abnormalities of the vagina (agenesis), uterus, fallopian tubes associated most commonly with an absent kidney (unilateral)
What is Vesicoureteral reflux (VUR)
- when urine flows backward up the urinary tract back towards the kidney
- commonest “surgical” cause of UTI
- may be diagnosed after the UTI
- may be diagnosed antenatally
- secondary reflux could arise when associated with other abnormalities
What is the consequence of VUR?
- nuclear medicine scan of the kidney
- damage to the kidney
- chronic scarring due to pyelonephritis
How is VUR managed?
- mostly non-operative management
- many will stop refluxing after ~age 5
- lengthening of the mucosal urinary tunnel will get longer as the kidney develops
- Uroprophylaxis
- can be corrected with a Sting
- an injection that narrows the opening of the ureter
What is hydronephrosis?
- commonly caused be a pelvic urinary junction obstruction
- infection is not common
- can be diagnosed antenatally
- investigations
- ultrasound
- nuclear medicine scan- MAG 3 scan
What is the posterior urethral valve (PUV)?
- valve created by mucosal folds at the bladder outlet in the posterior urethra
- diagnosed antenatally
- effects male children
- present very unwell
- outcomes depends on the extent of renal damage
What is mega-ureter?
- the ureter is abnormally dilated
- maybe due to reflux or an obstruction where the ureter joins the bladder
What other congenital abnormalities may people be born with?
- Buried penis
- penis is buried under excess skin in the pubic area or the scrotum can be corrected surgically
- Hypospadias
- abnormal position of the urethral meatus, not on the glands penis itself
- Virtualisation
- Ureterocele
- cystic vescico-urethral junction
- Undescended testis
- Inguinal hernia and hydrocele - caused by a failure for the testis to descend
What is an undescended testis managed?
- what are the different types
- Is a testis that cannot be manipulated to the bottom of the scrotum, without undue tension of the spermatic cord
- Impalpable testis: absent, intra-abdominal or intra-canicular
- Undescended testis: in the groin
- Ectopic testis: abdominal wall, thigh, base of penis or contra-lateral side
-
Ascending testis
- when it starts to retract back
What is the purpose of treating an undescended testis?
- allowing spermatogenesis to occur
- requires a temperature difference of 1 degree to be maintained which can be achieved if it is internal;
- if a testis becomes malignant it cannot be easily discovered
What has developed in the face at week 4 and 5 in a fetus?
- the large frontal nasal process
- also accommodates the developing brain
- maxillary process
- gives rise to the upper jaw
- mandibular process
- gives rise to the lower jaw
what has developed on the face at week 5 and 6 on a fetus
- further folding and elongation of the processes
- lateral nasal process, medial nasal process
- hyomandibular cleft
What has developed on the face at week 8 and 9 on a fetus?
- fusing of the median nasal processes to form philtrum of the upper lip
- external ear
- ear tubercles around the hyomandibular cleft
- hyoid bone
- laryngeal cartilages
What are the components of a basic facial structure?
- 1 x frontonasal
- 2 x nasomedial
- 2 x nasolateral
- 2 x maxillary
- 2 x mandibular
- maxillary and mandibular 1st pharyngeal arch
- mandibular arch
How does the palate form?
- what happens if this doesn’t occur properly
- develops from the maxillary process
- the fusion of the palatine shelves in the midline
- anteriorly a primary palate forms which will eventually become the soft palate
- if the fusion of these process does not occur properly it gives rise to
- cleft palate
- cleft lip
What structures make up the Pharyngeal Arches
- four arches
- mandibular
- hyoid
- third and fourth
- they are all covered by mesoderm
- cartilage
- nerve
- and have a branch of the aortic arch artery
What are the cranial nerve supplies to the pharyngeal apparatus?
- Arch 1: Maxillary nerve
- Arch 2: Facial Nerve
- Arch 3: Glossopharyngeal Nerve
- Arch 4: Vagus Nerve
What structures make up the pharyngeal apparatus?
What are the Arches of the Pharyngeal Apparatus
- Arch 1: Mandibular
- Arch 2: Hyoid
- Arch 3: Greater horn of the hyoid + part of the body
- Arch 4: Cartilages of the larynx
What are the key structures in the Mandibular Pharyngeal Arch (Arch 1)
- Nerve supply is CNV: Trigeminal nerve
- Muscles of mastication
- digastric belly
- masseter
- temporalis
- Meckel’s cartilage
- sphenomandibular ligament
- malleus
- incus
What are the key structures in the Hyoid Pharyngeal Arch (arch 2)?
- Nerve supply CN VII: Facial nerve
- Muscles of facial expression +
- stapedius muscle
- digastric belly
- auricularis
- occipitalis
Structures that develop from this arch
- Part of the body and lesser horn of the hyoid
- Stapes
- Styloid process
- Stylohyoid ligament
What are the key structures of the Pharyngeal Arches 3 + 4
- Nerve supply of the 3rd Arch: CN IX - glosso-pharyngeal
- part of the body + greater horn hyoid
- stylopharyngeus
- Nerve supply of the 4th Arch: X - vagus
- cartilages of the larynx
- pharyngeal muscles
What are key pharyngeal grooves?
- Tract of thyroglossal duct
- thyroglossal cyst or fistula if this persists after birth
Review where the tongue is in relation to the thyroid gland as it develops
