Diagnosis of Fetal Neurological Abnormalities in the Second and Third Trimesters

Arnold Chiari II Malformation is characterized by a banana-shaped cerebellum, not the presence of cisterna magna, normal cranial frontal bossing, or having no association with Spina Bifida.

Anencephaly is a serious birth defect where a baby is born without parts of the brain and skull. It is characterized by the absence of the cranial vault, cerebral hemispheres, bulging eyes, macroglossia, short neck, and polyhydramnios.

Cephalocele/encephalocele refers to a protrusion of intracranial contents through a defect in the skull, often occurring in the occipital region. This condition is associated with various other conditions such as hydrocephalus, spina bifida, polyhydramnios, and Meckel-Gruber Syndrome. It is not related to abnormalities in the knee joint, respiratory infections, or liver conditions.

Iniencephaly is a rare neural tube defect characterized by extreme retroflexion (hyperextension) of the head with absence of neck.

Hydrocephalus is a condition characterized by the buildup of CSF in the brain ventricles, leading to increased pressure. This can be caused by various factors such as obstructions or overproduction of CSF.

Aqueduct stenosis refers to the enlargement of the 3rd and lateral ventricles in the brain due to the obstruction of the aqueduct of Sylvius, which connects the 3rd and 4th ventricles. It is not related to narrowing of the spinal cord canal, blockage in blood vessels, or excessive production of cerebrospinal fluid.

Ventriculomegaly specifically refers to the dilation of ventricles without an enlargement of the cranium, often seen as compression of the choroid plexus with atria measuring over 1cm. The other options represent different conditions or scenarios that are not characteristic of ventriculomegaly.

Hydranencephaly is a rare condition characterized by the total absence of cerebral hemispheres, with the skull still present. It is not related to increased fluid in the brain, enlarged brain size, or brain hemorrhage.

Holoprocencephaly is a specific developmental disorder that affects the brain and face structure during early stages of pregnancy. It is not related to dementia, cancer, or skin disorders.

Porencephaly is a rare disorder characterized by the presence of cystic areas within the cerebral parenchyma, with hydranencephaly being the most severe form of this condition.

Dandy Walker Malformation is characterized by obstruction and dilation of the 4th ventricle, presence of a large cisterna magna, cerebellar vermis, and a large midline cystic structure in the posterior fossa. The incorrect answers do not describe the key features of this condition, thus making them inaccurate choices.

Agenesis of Corpus Callosum is a condition characterized by failure of development of connection between cerebral hemispheres. This results in structural abnormalities such as absent CSP, enlarged occipital horn, and enlarged 3rd ventricle.

Schizencephaly is a rare congenital disorder characterized by abnormal clefts or deep slits in the cerebral hemispheres. It is not related to skin conditions, heart diseases, or arthritis.

Lissencephaly is a condition characterized by the smooth appearance of the brain due to the lack of normal folds (sulci) and bumps (gyri). This is caused by abnormal neuronal migration during brain development.

Choroid Plexus Cysts can be associated with Trisomy 18 and are considered anomalies in that case. However, in most cases, they are a normal variant and typically resolve by 25 weeks gestation. There is no known association with Down syndrome, and they do not typically resolve after birth.

Microcephaly is a condition where the head circumference is significantly smaller than the average, typically below 3 standard deviations of normal. It can be caused by various factors including craniosynostosis, inherited factors, and exposure to certain substances. Additionally, it is often associated with intrauterine infections.

Potters Syndrome is a rare condition characterized by the absence or underdevelopment of the kidneys, leading to oligohydramnios, which in turn causes pulmonary hypoplasia, facial anomalies, and growth restriction. The ultrasound findings typically include oligohydramnios, empty bladder, absent kidneys, and anuria.

Ureteropelvic junction obstruction specifically refers to stenosis at the junction of the ureter and pelvis, causing dilation of the pelvis and calyces. This obstruction is the most common cause of severe hydronephrosis, leading to symptoms like oliguria.

Posterior Urethral Valve Obstruction is a condition where folds of the male urethra act as valves obstructing the excretion of urine. This leads to characteristic findings such as the 'keyhole sign', bilateral hydronephrosis, and oligohydramnios.

Prune Belly Syndrome is characterized by a massive dilation of the bladder causing pressure in the abdominal wall. It is commonly caused by Posterior Urethral Valves. The syndrome is associated with pulmonary hypoplasia due to oligohydramnios and bilateral hydrodistended bladder.

Gastroschisis is a condition characterized by an opening in the abdominal wall through which organs protrude, unlike the other incorrect options provided.

Omphalocele is a specific congenital condition characterized by a hernia of the umbilicus covered by a membrane with the possibility of the cord being visible in the mass. It is often associated with chromosomal abnormalities and should not be confused with other unrelated conditions such as skin rashes, heart abnormalities, or metabolic disorders.

Bladder extrophy refers to the exposure and protrusion of the bladder, often associated with other congenital abnormalities. It can be visualized on ultrasound by the absence of the bladder in its normal position and the presence of soft tissue protrusion in the lower abdominal wall.

Esophageal atresia is characterized by the discontinuation of the esophagus, with the ultrasound showing a small or absent fluid-filled stomach and the presence of polyhydramnios. The incorrect answers provided do not align with the diagnostic features of esophageal atresia.

Duodenal atresia is commonly associated with perinatal intestinal obstruction, karyotype abnormality, cardiac and vertebral abnormalities, Down syndrome, double bubble sign, and polyhydramnios. It is not associated with hepatic granuloma, pulmonary atresia, or renal agenesis.

Rhizomelic refers to short upper long bones, particularly in the context of skeletal dysplasias.

Mesomelic is a term used to describe disproportionately short lower long bones, which is a characteristic feature seen in certain types of skeletal dysplasias. Brachydactyly refers to shortening of the fingers or toes, Ectrodactyly is a condition where the middle digit is missing, and Achondroplasia is a genetic disorder that results in dwarfism.

Micromelic is a term used to describe unusually short limbs. The correct answer describes the common feature of short upper and lower long bones in individuals with Micromelic condition, leading to shorter than average limb length.