Aqueductal stenosis in infancy

Aqueductal stenosis (AqS) is a frequent cause of congenital hydrocephalus (HCP) (up to 70% of cases 1)), but occasionally may be the result of HCP. Patients with congenital AqS usually have HCP at birth or develop it within ≈ 2–3 mos. Congenital AqS may be due to an X-linked recessive gene 2).

Four types of congenital AqS described by Russell (summarized 3)):

1. forking: multiple channels (often narrowed) with normal epithelial lining that do not meet, separated by normal nervous tissue. Usually associated with other congenital abnormalities (spina bifida, myelomeningocele)

2. periaqueductal gliosis: luminal narrowing due to subependymal astrocytic proliferation

3. true stenosis: aqueduct histologically normal

4. septum

1)
Section of Pediatric Neurosurgery of the American Association of Neurological Surgeons. Pediatric Neurosurgery. New York 1982
2)
Matson DD. Neurosurgery of Infancy and Childhood. 2nd ed. Springfield: Charles C Thomas; 1969
3)
Nag TK, Falconer MA. Non-Tumoral Stenosis of the Aqueduct in Adults. Brit Med J. 1966; 2:1168–1170