Question: What is (are) Microhydranencephaly ?
Answer: Microhydranencephaly is a developmental abnormality that affects the brain. Signs and symptoms may include extreme microcephaly, scalp rugae (a series of ridges), profound developmental delay and severe intellectual disability. Imaging studies of the brain generally reveal incomplete brain formation and severe hydrocephalus (accumulation of fluid in the brain). In most cases, the underlying cause is unknown. Rarely, the condition is caused by changes (mutations) in the NDE1 gene and is inherited in an autosomal recessive manner. Treatment is based on the signs and symptoms present in each person.
Source: GARD

Question: What are the symptoms of Microhydranencephaly ?
Answer: What are the signs and symptoms of Microhydranencephaly? Microhydranencephaly is a developmental abnormality that affects the brain. Signs and symptoms can vary but generally include: Extreme microcephaly Scalp rugae (a series of ridges) Profound developmental delay Severe intellectual disability Spasticity Imaging studies of the brain generally reveal incomplete brain formation and severe hydrocephalus (accumulation of fluid in the brain). The Human Phenotype Ontology provides the following list of signs and symptoms for Microhydranencephaly. If the information is available, the table below includes how often the symptom is seen in people with this condition. You can use the MedlinePlus Medical Dictionary to look up the definitions for these medical terms. Signs and Symptoms Approximate number of patients (when available) Agenesis of corpus callosum - Athetosis - Autosomal recessive inheritance - Cerebellar hypoplasia - Generalized myoclonic seizures - Hydranencephaly - Hyperreflexia - Hypoplasia of the brainstem - Intellectual disability, progressive - Intellectual disability, severe - Macrotia - Microcephaly - Multiple joint contractures - Pachygyria - Prominent nasal bridge - Proptosis - Self-mutilation - Short stature - Skeletal muscle atrophy - Sloping forehead - Spastic tetraplegia - Talipes equinovarus - Ventriculomegaly - The Human Phenotype Ontology (HPO) has collected information on how often a sign or symptom occurs in a condition. Much of this information comes from Orphanet, a European rare disease database. The frequency of a sign or symptom is usually listed as a rough estimate of the percentage of patients who have that feature. The frequency may also be listed as a fraction. The first number of the fraction is how many people had the symptom, and the second number is the total number of people who were examined in one study. For example, a frequency of 25/25 means that in a study of 25 people all patients were found to have that symptom. Because these frequencies are based on a specific study, the fractions may be different if another group of patients are examined. Sometimes, no information on frequency is available. In these cases, the sign or symptom may be rare or common.
Source: GARD

Question: What causes Microhydranencephaly ?
Answer: What causes microhydranencephaly? In many cases, the exact, underlying cause of microhydranencephaly is unknown. There are reports of families in which the condition is caused by changes (mutations) in the NDE1 gene. In these rare cases, more than one family member (often a pair of siblings) had the condition.
Source: GARD

Question: Is Microhydranencephaly inherited ?
Answer: Is microhydranencephaly inherited? Most cases of microhydranencephaly occur sporadically in people with no family history of the condition. However, the condition can rarely affect more than one family member and be inherited in an autosomal recessive manner. In these cases, an affected person must have a mutation in both copies of the responsible gene in each cell. The parents of an affected person usually each carry one mutated copy of the gene and are referred to as carriers. Carriers typically do not have signs or symptoms of the condition. When two carriers of an autosomal recessive condition have children, each child has a 25% (1 in 4) chance to have the condition, a 50% (1 in 2) chance to be a carrier like each of the parents, and a 25% chance to not have the condition and not be a carrier.
Source: GARD

Question: How to diagnose Microhydranencephaly ?
Answer: How is microhydranencephaly diagnosed? A diagnosis of microhydranencephaly is generally suspected based on the presence of characteristic signs and symptoms. Additional testing can then be ordered to confirm the diagnosis. This generally consists of imaging studies to evaluate the brain for structural abnormalities and severe hydrocephalus (accumulation of fluid in the brain).
Source: GARD