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Congenital aqueductal stenosis has an estimated incidence of ~1:5000 births although the reported range varies greatly (3.7:1,000,000 to 1:2000) 5. Rarely it may be inherited in an X-linked recessive manner (Bickers-Adams-Edwards syndrome) 5.
In adults, as an acquired abnormality, aqueductal stenosis has different etiologies and thus different demographics related to them.
The clinical presentation depends on the severity and age of presentation as well as whether or not it is X-linked. In the infant with enlarging head size, bulging fontanelles and gaping cranial sutures are seen. Setting sun phenomenon may also be present. In X-linked form (Bickers-Adams-Edwards syndrome), which is associated with profound intellectual disability, clinical assessment would reveal bilateral adducted thumbs.
The usual symptoms and signs of raised intracranial pressure and chronic hydrocephalus may also be present, including headache, vomiting, decreased conscious state 3.
Adults with late-onset idiopathic aquedcutal stenosis more commonly have chronic onset of neurological symptoms 6.
aqueductal webs or diaphragms
MRI better delineates the extent of obstructive hydrocephalus with an enlargement (often marked) of the lateral and third ventricles. The aqueduct may show funnelling superiorly. The 4th ventricle is not dilated. In cases of secondary obstruction, the underlying abnormality may also be evident (e.g. web, tumor).
sagittal T2: the absence of flow-void signal intensity at the aqueductal level has been suggested as a sign of aqueductal stenosis 3
sagittal CISS: best demonstrates obstructing web
CSF flow study: decreased aqueductal stroke volume and peak systolic velocity
Treatment and prognosis
Recurrence risk for congenital cases is around 4% even when it is not X-linked.
- 1. Laurie A. Loevner. Case Review. (1999) ISBN: 032300430X - Google Books
- 2. McMillan J & Williams B. Aqueduct Stenosis. Case Review and Discussion. J Neurol Neurosurg Psychiatry. 1977;40(6):521-32. doi:10.1136/jnnp.40.6.521 - Pubmed
- 3. Stoquart-El Sankari S, Lehmann P, Gondry-Jouet C et al. Phase-Contrast MR Imaging Support for the Diagnosis of Aqueductal Stenosis. AJNR Am J Neuroradiol. 2009;30(1):209-14. doi:10.3174/ajnr.A1308 - Pubmed
- 4. Levitsky D, Mack L, Nyberg D et al. Fetal Aqueductal Stenosis Diagnosed Sonographically: How Grave is the Prognosis? AJR Am J Roentgenol. 1995;164(3):725-30. doi:10.2214/ajr.164.3.7863902 - Pubmed
- 5. Urban P, Louis R Caplan. Brainstem Disorders. (2011) ISBN: 9783642042027 - Google Books
- 6. Roland J, Price R, Kamath A et al. Hydrocephalus Presenting as Idiopathic Aqueductal Stenosis with Subsequent Development of Obstructive Tumor: Report of 2 Cases Demonstrating the Importance of Serial Imaging. J Neurosurg Pediatr. 2017;20(4):329-33. doi:10.3171/2017.5.PEDS1779 - Pubmed