Neuro-Oncology
NF2-related schwannomatosis
Dec. 13, 2024
Worddefinition
At vero eos et accusamus et iusto odio dignissimos ducimus qui blanditiis praesentium voluptatum deleniti atque corrupti quos dolores et quas.
Aqueductal stenosis …
- Updated 08.07.2024
- Released 11.16.2018
- Expires For CME 08.07.2027
Aqueductal stenosis
Introduction
Overview
Narrowing of the cerebral aqueduct of Sylvius is termed aqueductal stenosis. Cerebrospinal fluid flow is restricted but still occurs. Aqueductal atresia, by contrast, is a total obliteration of the cerebral aqueduct, leaving only a few ependymal clusters and rosettes in its place that enable no CSF flow. The aqueduct is the conduit between the third and fourth cerebral ventricles. When narrowed, CSF accumulation dilates the upstream lateral and third ventricles and causes ventriculomegaly that often can be detected in fetal ultrasound and MRI images as early as the second trimester. The consequences and treatment of this condition are discussed in this article.
Key points
Stenosis of the cerebral aqueduct of Sylvius:
|
• May be congenital (genetic origin) or acquired. | |
|
• May be isolated; associated with other brain malformations, vascular anomalies, or genetic syndromes; or secondary to acquired lesions that infiltrate, compress, or cause inflammation and gliosis in periaqueductal tissue. | |
|
• Posthemorrhagic hydrocephalus may be due to intra-aqueductal blockage by blood descending from the lateral and third ventricles in intraventricular hemorrhage in the perinatal period. | |
|
• Restricts the circulation of CSF, resulting in dilatation of the lateral and third ventricles increased intraventricular pressure. | |
|
• May result in potentially reversible thinning of the cerebral mantle and corpus callosum. | |
|
• May be progressive, debilitating, or even fatal. | |
|
• Does not cause epilepsy. |
Historical note and terminology
Hydrocephalus has been depicted in the descriptive literature of the seventeenth and eighteenth centuries and has presumably occurred throughout human history. The most frequent cause of hydrocephalus in the perinatal period is isolated aqueductal stenosis.
Clinical manifestations
Presentation and course
The three leading causes of congenital hydrocephalus are neural tube defects (meningomyelocele), aqueductal stenosis, and posterior fossa malformations (29). This article is confined to the discussion of isolated aqueductal stenosis and secondary changes. In this condition, causes and timing are often unclear. However, in some cases the cause is known, wherein malformations compress the aqueduct, resulting in primary stenosis. These include encephalocele, Dandy-Walker malformation, and lumbosacral meningomyelocele (often with Chiari malformation). Though isolated aqueductal stenosis is the most frequent form, a large percentage of patients manifest additional anomalies (36).
One study (N=12) showed the variability in progression of fetal ventriculomegaly due to aqueductal stenosis (38). One-third of cases were terminated as further progression could not be observed because of severe ventriculomegaly; others progressed rapidly in the third trimester, some evolved slowly throughout the second and third trimesters, and others remained stable. Premature delivery or cystic parenchymal change occurred in those who experienced rapid development; except for the stable cases, all required surgical intervention.
Clinical findings in the newborn include bulging anterior fontanelle, splayed cranial sutures, decreased activity, feeding difficulty, vomiting, apnea, bradycardia, setting-sun sign, developmental delay, and failure to thrive; findings in older patients include abnormal hypothalamic function, upward gaze, spasticity, blindness, and intellectual decline (11). Acute bilateral ptosis has been reported, with full eye movement; resolution was achieved with third ventriculostomy (56).
Imaging studies, both fetal ultrasound and MRI and postnatal MRI, reveal generalized ventriculomegaly and nonvisualization of the cerebral aqueduct as seen in midsagittal and axial MRI views (04). An additional feature is obliteration of the subarachnoid space over the cerebral convexities so that the brain appears closely pushed against the inner table of the calvarium. By contrast, in adult normal-pressure hydrocephalus, this subarachnoid space is generally preserved (57).
An important negative feature is that even severe ventriculomegaly with increased pressure in hydrocephalus is not epileptogenic. However, if the hydrocephalus due to aqueductal atresia is associated with other cerebral dysgeneses, particularly involving the cerebral cortex, seizures may be a manifestation of the cortical lesions.
Prognosis and complications
In one study of isolated aqueductal stenosis, mortality averaged 40%, with over one-half of deaths occurring in the first three postnatal months (27). In that study, 95% of patients underwent ventricular shunting, but only 10% were developmentally normal at long-term follow-up. This latter finding has been borne out in another study showing the poor prognosis of shunting in pediatric patients with hydrocephalus (19). In that study (follow-up period at least 20 years), one third of patients were deceased, one half were employed, and nearly one third had a severe mental handicap.
Clinical vignette
The following photographs depict CNS tissue from four individuals with aqueductal stenosis. In the first three, ventriculomegaly is evident in coronal sections of cerebrum; in the fourth image, an anomalous aqueduct is shown microscopically. Three postnatal patients had additional, extracranial anomalies that led to death--in two cases before shunting was instituted. For privacy concerns, additional clinical details are not provided.
Biological basis
The cerebral aqueduct of Sylvius develops from the central canal within the central embryonic neural tube at the level of the mesencephalic vesicle, which matures to become like the midbrain.
Pathogenesis. The neural tube is characterized by bilateral symmetry and cephalization and is achieved by the establishment of three axes with genetic gradients of expression in each opposing directions along each axis. The cerebral aqueduct is more affected by genes acting in the dorsoventral gradient of the vertical axis, ie, “dorsalizing” gene families such as PAX (42; 41; 42; 45). In some malformations, such as holoprosencephaly, aqueductal stenosis occurs with mutation in genes of each of the three axes; if the rostrocaudal gradient of the longitudinal axis reaches as far caudally as the midbrain, aqueductal atresia usually occurs. The atresia is enhanced by genes of the dorsoventral gradient of the vertical axis and genes of the mediolateral gradient of the horizontal axis, such that the colliculi are noncleaved or fused as a midline dome of the tectal roof of the midbrain and the oculomotor nuclei of each side are fused in the midline, but the ventrally situated cerebral peduncles remain paired and separate (44). The facial dysmorphisms midfacial hypoplasia frequent in lobar and semilobar holoprosencephaly are due to the mesencephalic neural crest not forming or migrating properly and does not occur in cases of alobar holoprosencephaly in which the rostrocaudal gradient in the longitudinal axis does not extend as far caudally as the mesencephalon (44). Stenosis or atresia of the cerebral aqueduct usually also involves poor development of the roof plate and its ependymal processes that form the dorsal medial septum extending to the intercollicular fissure. In isolated aqueductal stenosis, the genetic/neuropathological pathogenesis probably is similar but has been less studied and is not yet well documented.
When fully developed, the aqueduct courses through the midbrain; it is bordered by periaqueductal (or central) gray matter, the tegmentum ventrally, and tectum dorsally. In the newborn, the aqueduct is about 0.5 mm in diameter by 13 mm in length; it is narrower at each end and somewhat wider at its center (16). In the adult, this variability continues. The aqueduct averages 1 to 1.4 mm in diameter and about 14 mm in length. Dimensions for adults, obtained by MRI, differ from postmortem measures and vary with age, with diameter increasing and length decreasing as patients get older and the cerebrum shrinks (31). The cerebral aqueduct initially is lined by primitive neuroepithelial cells, which differentiate as ependyma and a transient form a pseudostratified epithelium, which soon becomes a simple (one cell thick) cuboidal ependymal epithelium, as with the rest of the ventricular system. Loss of p73 in ependymal cells during the perinatal period can lead to aqueductal stenosis by obliteration of the ependymal-lined lumen (17).
Chronic aqueductal compression by a mass lesion may lead to periaqueductal gliosis and at least partial obliteration of the lumen. Localized swelling in the periventricular and periaqueductal tissue, in particular, also contributes to narrowing and eventual obstruction of the lumen of the aqueduct (06). Dysgenesis of the mesencephalic tectum associated with aqueductal stenosis or atresia is more likely related to genetic gradients than to compression (51).
Classification. Aqueductal stenosis was previously classified as malformative or acquired (39). In the former, three types were recognized: true stenosis or due to an anomalous septum (both rare) or stenosis due to forking of the lumen. When forking is identified by careful microscopy, two channels are separated by normal CNS tissue.
The absence of gliosis in the young patient may reflect the early age of tissue damage at a time when the fetus is unable to mount a reaction (02). At present aqueductal stenosis may be reclassified into three forms: (1) isolated; (2) associated with other brain malformations, genetic syndromes, or specific identified genetic mutations; (3) acquired, induced by chronic pressure on the midbrain tectum, infiltration by midbrain tumors or inflammation as might be associated with congenital, or early postnatal viral encephalitis.
Etiology and pathogenesis
Without history or corroborating imaging, the cause of congenital stenosis is sometimes unknown, although a perturbation in embryonic development may be postulated in some cases. Because the aqueduct is so narrow, it can be obstructed by debris arising in the ventricular system (for example, sloughed cells or purulent material from an infection or blood products stemming from a hemorrhage). Intraventricular hemorrhages in late fetal life or the neonatal period may cause blockage of the cerebral aqueduct by intra-aqueductal thrombosis (posthemorrhagic hydrocephalus). Chiari II malformation may result in narrowing of the aqueduct and often accompanies lumbo-sacral meningomyelocele. Some cases also include bilateral congenital agenesis of the foramen of Monro for CSF flow from the lateral ventricles into the third ventricle (25). Approximately 5% of cases of isolated aqueductal stenosis are X-linked.
Other midline defects in the brain may accompany aqueductal stenosis in complex brain malformations. Rhombencephalosynapsis (fusion of the medial surfaces of the cerebellar hemispheres and dentate nuclei with hypoplasia or absence of the vermis) is associated with aqueductal stenosis in a significant number of cases. In one review of 20 affected children, 13 (65%) had aqueductal stenosis and hydrocephalus; the finding was uniform in those with complete rhombencephalosynapsis (55). In another study of 30 patients with aqueductal stenosis, one-half manifested rhombencephalosynapsis (24). Rhombencephalosynapsis is associated with aqueductal stenosis in some cases of alobar holoprosencephaly, but most often rhombencephalosynapsis occurs in septo-optic-pituitary dysplasia without aqueductal stenosis (see the Medlink topic “Rhombencephalosynapsis”).
Apart from syndromic aqueductal stenosis as part of a complex brain malformation, a genetic basis for isolated aqueductal stenosis has not been well established, but chromosomal and copy number variants and several single gene mutations have now been demonstrated (15). An example is a pathogenic variant of CCDC88C gene in fetuses with prenatal hydrocephalus and aqueductal forking and atresia, confirmed neuropathologically; this gene encodes the protein DAPLE, which contributes to ependymal cell planar polarity by inhibiting the WNT signaling pathway (30).
Acquired stenosis, even with late onset, may be due to compression from a mass. Such masses may be tectal tumors that infiltrate or compress such as gliomas and pinealomas, pineal cysts, supracollicular lipomas, or vascular malformations (49; 10; 22; 05; 54). Compression of the aqueduct also may result from a persistent and enlarging suprapineal recess of the third ventricle, which usually is a transitory fetal structure or adjacent scarring or gliosis (43). Some of these mass lesions may be congenital. In this sense, a “congenital” narrowing, which is one present at birth, may have an acquired basis.
Epidemiology
By older estimates, isolated aqueductal stenosis occurs in two in every 1000 births (36). With the increase in diagnostic abilities, this figure would be expected to change. High quality registry-based data worldwide may clarify the reasons for the higher incidence of hydrocephalus and aqueductal stenosis in lower income parts of the world (50).
Prevention
Congenital isolated aqueductal stenosis cannot be prevented.
Differential diagnosis
Isolated aqueductal stenosis must be differentiated from cases associated with other CNS or extracranial anomalies. This requires careful imaging. Venous anomalies, including arteriovenous fistulas involving the great vein of Galen, can compress or otherwise obstruct the cerebral aqueduct and imitate the presentation of congenital aqueductal stenosis (22; 05). Perinatal intraventricular hemorrhages in preterm neonates can obstruct the aqueduct (35). Spontaneous third ventriculostomy may occur in some cases of congenital aqueductal stenosis (37). Aqueductal webs in adults occasionally alter CSF flow and can be detected by MRI flow dynamics (58).
Diagnostic workup
Prenatal imaging employs ultrasound in the second trimester and, if fetal hydrocephalus is suspected, it is followed by additional high-resolution ultrasound and fetal MRI in the late second or third trimester (11; 14). The chief diagnostic criterion for ventriculomegaly is an atrial diameter greater than 10 mm measured ultrasonographically. Additional craniometric data based on a large international study have been published (09). Ventriculomegaly due to aqueductal stenosis may be differentiated from other malformative or disruptive causes: brain parenchyma may be compressed, but not otherwise reduced in mass; lateral ventricles are enlarged anteriorly and posteriorly; the third ventricle is dilated, with transverse diameter greater than 2 mm; the choroid plexus is dangling; the fourth ventricle is normal; and, cranial size and configuration are normal with normal-appearing posterior fossa (14). Additional findings may implicate aqueductal stenosis as the cause of enlarging ventricles, chiefly funnel-shaped aqueduct and even direct visualization of an obstructing web or blood clot in the aqueduct (21). Venous malformations require MR angiography in addition to the standard imaging sequences (22; 05). Agenesis of the internal carotid artery may be associated with aqueductal stenosis (54). Perinatal intraventricular hemorrhages often obstruct the aqueduct causing hydrocephalus with dilatation of the third and lateral ventricles (35).
In addition to CNS imaging, a total anatomic survey is indicated to rule out additional anomalies. Infectious causes (eg, rubella, cytomegalovirus, toxoplasmosis) are possible and need to be explored by appropriate testing, including maternal serology. A hematologic workup is indicated in cases of fetal hemorrhage. Detailed anatomic and genetic workup is necessary to confirm or rule out syndromes or specific etiologies (for example, L1CAM mutation or X-linked hydrocephalus). Expectant management should be arranged, in an effort to offset the risk of premature birth with that of progressing hydrocephalus (14). In cases of pregnancy termination, fetal autopsy is important to further delineate findings.
Management
Ventricular shunting has been used for decades, whereby CSF drains from a ventricle to the peritoneal cavity, or less often, the systemic venous return or right atrium. Shunts may become blocked over time and require revision. Milder forms of aqueductal obstruction, those developing from the formation of thin membranes for example, can be treated with aqueductoplasty, sometimes combined with stent placement. Surgical approaches for this procedure may be pre-coronal, suboccipital, or trans-fourth ventricle via the foramen magnum and are used in both children and adults (40; 08). Lumboperitoneal shunting has proven successful, particularly in patients with slit ventricles or ventriculoperitoneal shunt failure (32).
Despite early discouraging results with fetal shunting decades ago, safe prenatal ventriculo-amniotic shunting seems increasingly possible with developments in diagnosis, shunt and valve implements, and surgical technique (12; 34). This will require a carefully controlled prospective study (14). Families of infants requiring shunting may suffer stress and may benefit from intervention, especially in cases of increased morbidity and socioeconomic challenges (01). A multicenter North American study demonstrated that accurate prenatal diagnosis of aqueductal stenosis not only can be made by precision fetal neuroimaging but at gestational ages amenable to in utero intervention (13).
Neuroendoscopic surgical techniques are now employed with increasing frequency in cases of intraventricular infection to lyse and remove purulent material or other debris and irrigate the ventricular cavities with antibiotic saline; secondary hydrocephalus in such cases may require additional shunting (20). Endoscopic septum pellucidotomy may be required for unilateral hydrocephalus. The neural and vascular anatomy of the septum have been described, and ideal areas for surgery have been identified (03). Aqueductal stenosis due to pineal cyst has been treated by endoscopy, with resolution in about 80% of cases (10). However, endoscopic aqueductoplasty has a high risk of long-term failure and is not recommended by some authors who recommend endoscopic third ventriculoscopy as a preferred surgical approach (Marx et el 2019). Third ventriculostomy can relieve hydrocephalus secondary to aqueductal stenosis (07; 48; 09).
Outcomes
Functional outcome is highly variable but appears to be based largely on the severity of ventriculomegaly and presence and effect of additional malformations (28; 36). Patients who are born prematurely and develop hydrocephalus secondary to CNS hemorrhage have reduced motor function and difficulties in behavioral and intellectual development, hearing, and vision (18). In one long-term (mean 5.9 years) follow-up study of 41 patients, nearly one-half had epilepsy and well over one-half were developmentally delayed; three-quarters were shunt-dependent; one-third were normal neurologically (52).
A prospective comparison of 81 patients treated with either third ventriculostomy or primary shunting revealed no difference in outcomes between the two groups (800 days median follow-up) or between those who sustained ventriculostomy failure and required later shunting (26). Stenosis may recur following aqueductoplasty alone and may require re-operation with stent placement; transient vertical diplopia or upgaze weakness have been observed in a small subset of patients (40).
The search for predictors of outcome continues, one finding being the effacement of sulci seen on imaging, which is taken as evidence for cortical maldevelopment and reduced prognosis (28).
Special considerations
Pregnancy
The recurrence risk for isolated aqueductal stenosis is estimated at 4% (53). This estimate is based on older studies and could change in the future as diagnosis improves. The hereditability of X-linked hydrocephalus is different of course and is indication for genetic counseling.
Delivery of an infant with severe ventriculomegaly and expansion of the calvaria is complex and in all likelihood requires caesarian section. The value of prenatal diagnosis and preparation for the delivery cannot be overstated.
Anesthesia
An obvious but important point is that the pharmacokinetics of infants and children differ from those of adults and must be considered in patients requiring anesthesia (23). Anesthetic approaches must take into account immature neural pathways and the possibility of developing propofol infusion syndrome but otherwise tend to vary among practitioners and institutions (47).
Media
References
- 01
- Agajany N, Gigi M, Ross J, et al. The impact of neonatal posthemorrhagic hydrocephalus of prematurity on family function at preschool age. Early Hum Dev 2019;137:104827. PMID 31374456
- 02
- Alvord EC Jr. The pathology of hydrocephalus. In: Fields WS, Desmond MM, Charles C, editors. Disorders of the Developing Nervous System. Springfield, Illinois: Thomas, 1961:343.
- 03
- Barany L, Meszaros C, Ganslandt O, Buchfelder M, Kurucz P. Neural and vascular architecture of the septum pellucidum: an anatomical study and considerations for safe endoscopic septum pellucidotomy. J Neurosurg 2019:1-10. PMID 31374555
- 04
- Barkovich AJ, Raybaud C. Pediatric neuroimaging. 5th ed. Philadelphia, PA: Lippincott Williams & Wilkins, 2012.
- 05
- Bogovski S, Sirakova K, Sirakov A, Vladev G, Sirakov S. Developmental venous anomaly causing obstructive hydrocephalus due to aqueductal stenosis: a case report. Folia Med (Plovdiv) 2022;64(5):829-33. PMID 36876539
- 06
- Chou D, Vardakis JC, Guo L, Tully BJ, Ventikos Y. A fully dynamic multi-compartamental poroelastic system: application to aqueductal stenosis. J Biomech 2016;49(11):2306-12. PMID 26671218
- 07
- Cinalli G, Spennato P, Nastro A, et al. Hydrocephalus in aqueductal stenosis. Childs Nerv Syst 2011;27(10):1621-42. PMID 21928028
- 08
- Cinalli G, Spennato P, Savarese L, et al. Endoscopic aqueductoplasty and placement of a stent in the cerebral aqueduct in the management of isolated fourth ventricle in children. J Neurosurg 2006;104(1 Suppl):21-7. PMID 16509476
- 09
- Coulter IC, Kulkarni AV, Sgouros S, et al. Cranial and ventricular size following shunting or endoscopic third ventriculostomy (ETV) in infants with aqueductal stenosis: further insights from the International Infant Hydrocephalus Study (IIHS). Childs Nerv Syst 2020;36(7):1407-14. PMID 31965292
- 10
- Davidson L. Endoscopic management of pineal cyst-associated aqueductal stenosis. Acta Neurochir (Wien) 2020;162(12):2975-82. PMID 32562121
- 11
- Emery SP, Hogge WA, Hill LM. Accuracy of prenatal diagnosis of isolated aqueductal stenosis. Prenat Diagn 2015a;35(4):319-24. PMID 25348577
- 12
- Emery SP, Greene S, Hogge WA. Fetal therapy for isolated aqueductal stenosis. Fetal Diagn Ther 2015b;38(2):81-5. PMID 25997519
- 13
- Emery SP, Lopa S, Peterson E, et al. Prenatal diagnosis of fetal aqueductal stenosis: a multicenter prospective observational study through the North American fetal therapy network. Fetal Diagn Ther 2024;51(3):216-24. PMID 38320542
- 14
- Emery SP, Narayanan S, Greene S. Fetal aqueductal stenosis: prenatal diagnosis and intervention. Prenat Diagn 2020;40(1):58-65. PMID 31306500
- 15
- Etchegaray A, Juárez-Peñalva S, Petracci F, Igarzabal L. Prenatal genetic considerations in congenital ventriculomegaly and hydrocephalus. Childs Nerv Syst 2020;36(8):1645-60. PMID 32006096
- 16
- Fenichel GM. Hydrocephalus and congenital tumors. In: Fenichel GM, editor. Neonatal Neurology. 4th ed. Elsevier Inc, 2007:187-98.
- 17
- Fujitani M, Sato R, Yamashita T. Loss of p73 in ependymal cells during the perinatal period leads to aqueductal stenosis. Sci Rep 2017;7(1):12007. PMID 28931858
- 18
- Gigi M, Roth J, Eshel R, Constantini S, Bassan H. Health-related quality of life after post-haemorrhagic hydrocephalus in children born preterm. Dev Med Child Neurol 2019;61(3):343-9. PMID 30187913
- 19
- Gmeiner M, Wagner H, Schlögl C, et al. Adult outcome in shunted pediatric hydrocephalus: long-term functional, social, and neurocognitive results. World Neurosurg 2019;132:e314-23. PMID 31479789
- 20
- Guan F, Peng WC, Huang H, et al. Application of neuroendoscopic surgical techniques in the assessment and treatment of cerebral ventricular infection. Neural Regen Res 2019;14(12):2095-2103. PMID 31397347
- 21
- Heaphy-Henault KJ, Guimaraes CV, Mehollin-Ray AR, et al. Congenital aqueductal stenosis: findings at fetal MRI that accurately predict a postnatal diagnosis. AJNR Am J Neuroradiol 2018;39(5):942-8. PMID 29519789
- 22
- Higa N, Dwiutomo R, Oyoshi T, Tanaka S, Bohara M, Yoshimoto K. A case of developing obstructive hydrocephalus following aqueductal stenosis caused by developmental venous anomalies. Childs Nev Syst 2020;36(7):1549-55. PMID 31907600
- 23
- Kaye AD, Fox CJ, Padnos IW, et al. Pharmacologic considerations of anesthetic agents in pediatric patients: a comprehensive review. Anesthesiol Clin 2017;35(2):e73-94. PMID 28526162
- 24
- Kline-Fath BM, Arroyo MS, Calvo-Garcia MA, Horn PS, Thomas C. Prenatal aqueduct stenosis: association with rhombencephalosynapsis and neonatal outcome. Prenat Diagn 2018;38(13):1028-34. PMID 30229955
- 25
- Konar SK, Shukla D, Devi BI. Neuroendoscopic management of coexisting congenital agenesis of bilateral foramen of Monro with aqueductal stenosis and Chiari malformation: case report and review of the literature. World Neurosurg 2018;18:55-8. PMID 30017764
- 26
- Kulkarni AV, Sgouros S, Constantini S; et al. Outcome of treatment after failed endoscopic third ventriculostomy (ETV) in infants with aqueductal stenosis: results from the International Infant Hydrocephalus Study (IIHS). Childs Nerv Syst 2017;33(5):747-52. PMID 28357554
- 27
- Levitsky DB, Mack LA, Nyberg DA, et al. Fetal aqueductal stenosis diagnosed sonographically: how grave is the prognosis? AJR Am J Roentgenol 1995;164(3):725-30. PMID 7863902
- 28
- Li Y, Estroff JA, Mehta TS, et al. Ultrasound and MRI of fetuses with ventriculomegaly: can cortical development be used to predict postnatal outcome? AJR Am J Roentgenol 2011;196:1457-67. PMID 21606314
- 29
- Lu VM, Shimony N, Jallo GI, Niazi TN. Infant hydrocephalus. Pediatr Rev 2024;45(8):450-60. PMID 39085190
- 30
- Marguet F, Vezain M, Marcorelles P, et al. Neuropathological hallmarks of fetal hydrocephalus linked to CCDC88C pathogenic variants. Acta Neuropathol Comm 2021;9(1):104. PMID 34092257
- 31
- Matys T, Horsburgh A, Kirollos RW, et al. The aqueduct of Sylvius: applied 3-T magnetic resonance imaging anatomy and morphometry with neuroendoscopic relevance. Neurosurgery 2013;73(2 Suppl Operative):ons132-40. PMID 23615083
- 32
- Marupudi NI, Harris C, Pavri T, et al. The role of lumboperitoneal shunts in managing chronic hydrocephalus with slit ventricles. J Neurosurg Pediatr 2018:1-6. PMID 30239284
- 33
- Marx S, Baldauf J, Matthes M, Gaab MR, Schroeder HWS. Long-term reliability of neuroendoscopic aqueductoplasty in idiopathic aqueductal stenosis-related hydrocephalus. Neurosurgery 2019;85(1):91-5. PMID 29878198
- 34
- Peiro JL, Dal Fabbro M. Fetal therapy for congenital hydrocephalus – where we came from and where we are going. Childs Nerv Syst 2020;36(8):1697-712. PMID 32601902
- 35
- Pindrik J, Schulz L, Drapeau A. Diagnosis and surgical management of neonatal hydrocephalus. Semin Pediatr Neurol 2022;42:100969. PMID 35868728
- 36
- Pisapia JM, Sinha S, Zarnow DM, Johnson MP, Heuer GG. Fetal ventriculomegaly: diagnosis, treatment, and future directions. Childs Nerv Syst 2017;33(7):1113-23. PMID 28510072
- 37
- Ragab OAA, Fathalla H, El Halaby W, Maher W, Hafez M, Zohdi A. Spontaneous third ventriculostomy in cases of aqueductal stenosis: a retrospective case series. World Neurosurg 2023;176:e408-14. PMID 37245667
- 38
- Rault E, Lacalm A, Massoud M, et al. The many faces of prenatal imaging diagnosis of primitive aqueduct obstruction. Eur J Paediatr Neurol 2018;22(6):910-8. PMID 30174220
- 39
- Russell DS. Observations on the Pathology of Hydrocephalus. Special Report Series Number 265. London: Medical Research Council, 1949.
- 40
- Sansone JM, Iskandar BJ. Endoscopic cerebral aqueductoplasty: a trans-fourth ventricle approach. J Neurosurg 2005;103(5 Suppl):388-92. PMID 16302609
- 41
- Sarnat HB. Cerebral dysgenesis. Embryology and clinical expression. Oxford, NY: Oxford University Press, 1992:137-8.
- 42
- Sarnat HB. Molecular genetic classification of central nervous system malformations. J Child Neurol 2000;15(10):675-87. PMID 11063082
- 43
- Sarnat HB. Transitory and vestigial structures of the developing human nervous system. Pediatr Neurol 2021;123:86-101. PMID 34416613
- 44
- Sarnat HB, Flores-Sarnat L. Neuropathological research strategies in holoprosencephaly. J Child Neurol 2001;16(12):918-31. PMID 11785508
- 45
- Sarnat HB, Flores-Sarnat L. Integrative classification of morphology and molecular genetics in central nervous system malformations. Am J Med Genet 2004;126A(4):386-92. PMID 15098236
- 46
- Sarnat HB, Menkes JH. How to construct a neural tube. J Child Neurol 2000;15(2):110-24. PMID 10695896
- 47
- Sloan T. Anesthesia and intraoperative neurophysiological monitoring in children. Childs Nerv Syst 2010;26(2):227-35. PMID 19888583
- 48
- Spennato P, Tazi S, Bekaert O, Cinalli G, Decq P. Endoscopic third ventriculostomy for idiopathic aqueductal stenosis. World Neurosurg 2013;79(suppl 2):S21.e13-20. PMID 22381825
- 49
- Steinbok P, Boyd MC. Periaqueductal tumor as a cause of late-onset aqueductal stenosis. Childs Nerv Syst 1987;3(3):170-4. PMID 3308086
- 50
- Tamber MS. Insights into the epidemiology of infant hydrocephalus. Childs Nerv Syst 2021;37(11):3305-11. PMID 33839901
- 51
- Tan AP, Priego G. Thanatrophic dysplasia type 1 with tectal plate dysplasia and aqueductal stenosis. Childs Nerv Syst 2019;35(6):1059-61. PMID 30610483
- 52
- Tonetti DA, Richter B, Andrews E, Xu C, Emery SP, Greene S. Clinical outcomes of isolated congenital aqueductal stenosis. World Neurosurg 2018;114:e976-81. PMID 29588243
- 53
- Varadi V, Toth Z, Torok O, Papp Z. Heterogeneity and recurrence risk for congenital hydrocephalus (ventriculomegaly): a prospective study. Am J Med Genet 1988;29:305-10. PMID 3354602
- 54
- Vasquez-Gregorio R, Jiménez-Guerra R, Cano-Nigenda V, Garfias-Rau Y. Agenesis of the right internal carotid artery and aqueductal stenosis in a child with hydrocephalus, the role of endoscopic third ventriculostomy: a case report. Childs Nerv Syst 2022;38(8):1631-5. PMID 35175366
- 55
- Whitehead MT, Choudhri AF, Grimm J, Nelson MD. Rhombencephalosynapsis as a cause of aqueductal stenosis: an under-recognized association in hydrocephalic children. Pediatr Radiol 2014;44(7):849-56. PMID 24633306
- 56
- Wu M, Ge X, Li Y, et al. Hydrocephalus due to aqueductal stenosis presenting with acute bilateral ptosis: case report. Br J Neurosurg 2019;1-3. PMID 31845609
- 57
- Yamada S. [Hydrocephalus]. No Shinkei Geka 2021;49(2):317-27. PMID 33762452
- 58
- Yilmaz TF, Sari L, Toprak H. Advanced cerebrospinal fluid flow: MRI findings of aqueductal stenosis caused by web. J Clin Ultrasound 2024;52(2):201-7. PMID 38013602
Contributors
All contributors' financial relationships have been reviewed and mitigated to ensure that this and every other article is free from commercial bias.
Author
-
Harvey B Sarnat MS MD FRCPC
Dr. Sarnat of the University of Calgary has no relevant financial relationships to disclose.
See Profile
Former Authors
- Joseph R Siebert PhD
Patient Profile
- Age range of presentation
-
- 0 month to 65+ years
- Sex preponderance
-
- Female = male
- Heredity
-
- Heredity may be a factor
- Population groups selectively affected
-
- none
- Occupation groups selectively affected
-
- none
ICD & OMIM codes
- ICD
-
- Malformations of aqueduct of Sylvius: Q03.0
- ICD-11
-
- Hydrocephalus with stenosis of the aqueduct of Sylvius: LA04.0
- OMIM
-
- Hydrocephalus due to congenital stenosis of aqueduct of Sylvius: 236635
This is an article preview.
Start a Free Account
to access the full version.
-
Nearly 3,000 illustrations, including video clips of neurologic disorders.
-
Every article is reviewed by our esteemed Editorial Board for accuracy and currency.
-
Full spectrum of neurology in 1,200 comprehensive articles.
-
Listen to MedLink on the go with Audio versions of each article.
Questions or Comment?
MedLink®, LLC
3525 Del Mar Heights Rd, Ste 304
San Diego, CA 92130-2122
Toll Free (U.S. + Canada): 800-452-2400
US Number: +1-619-640-4660
Support: service@medlink.com
Editor: editor@medlink.com
ISSN: 2831-9125
Also in This Category
-
-
Developmental Malformations
X-linked hydrocephalus (L1 syndrome)
Dec. 12, 2024
-
General Child Neurology
Breath-holding spells
Nov. 25, 2024
-
Developmental Malformations
Cerebro-oculo-facio-skeletal syndrome
Nov. 22, 2024
-
General Child Neurology
Acute cerebellar ataxia in children
Oct. 29, 2024
-
Headache & Pain
Headache in children: overview and treatment approaches
Oct. 29, 2024
-
Headache & Pain
Alternating hemiplegia of childhood
Oct. 29, 2024
-
Epilepsy & Seizures
Pyridoxine/P5P-dependent developmental epileptic encephalopathy
Oct. 14, 2024